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diff --git a/scripts/kconfiglib.py b/scripts/kconfiglib.py new file mode 100644 index 0000000..0da2735 --- /dev/null +++ b/scripts/kconfiglib.py @@ -0,0 +1,5976 @@ +# Copyright (c) 2011-2018, Ulf Magnusson +# SPDX-License-Identifier: ISC + +""" +Overview +======== + +Kconfiglib is a Python 2/3 library for scripting and extracting information +from Kconfig (https://www.kernel.org/doc/Documentation/kbuild/kconfig-language.txt) +configuration systems. + +See the homepage at https://github.com/ulfalizer/Kconfiglib for a longer +overview. + +Using Kconfiglib on the Linux kernel with the Makefile targets +============================================================== + +For the Linux kernel, a handy interface is provided by the +scripts/kconfig/Makefile patch, which can be applied with either 'git am' or +the 'patch' utility: + + $ wget -qO- https://raw.githubusercontent.com/ulfalizer/Kconfiglib/master/makefile.patch | git am + $ wget -qO- https://raw.githubusercontent.com/ulfalizer/Kconfiglib/master/makefile.patch | patch -p1 + +Warning: Not passing -p1 to patch will cause the wrong file to be patched. + +Please tell me if the patch does not apply. It should be trivial to apply +manually, as it's just a block of text that needs to be inserted near the other +*conf: targets in scripts/kconfig/Makefile. + +Look further down for a motivation for the Makefile patch and for instructions +on how you can use Kconfiglib without it. + +If you do not wish to install Kconfiglib via pip, the Makefile patch is set up +so that you can also just clone Kconfiglib into the kernel root: + + $ git clone git://github.com/ulfalizer/Kconfiglib.git + $ git am Kconfiglib/makefile.patch (or 'patch -p1 < Kconfiglib/makefile.patch') + +Warning: The directory name Kconfiglib/ is significant in this case, because +it's added to PYTHONPATH by the new targets in makefile.patch. + +The targets added by the Makefile patch are described in the following +sections. + + +make [ARCH=<arch>] iscriptconfig +-------------------------------- + +This target gives an interactive Python prompt where a Kconfig instance has +been preloaded and is available in 'kconf'. To change the Python interpreter +used, pass PYTHONCMD=<executable> to make. The default is "python". + +To get a feel for the API, try evaluating and printing the symbols in +kconf.defined_syms, and explore the MenuNode menu tree starting at +kconf.top_node by following 'next' and 'list' pointers. + +The item contained in a menu node is found in MenuNode.item (note that this can +be one of the constants kconfiglib.MENU and kconfiglib.COMMENT), and all +symbols and choices have a 'nodes' attribute containing their menu nodes +(usually only one). Printing a menu node will print its item, in Kconfig +format. + +If you want to look up a symbol by name, use the kconf.syms dictionary. + + +make scriptconfig SCRIPT=<script> [SCRIPT_ARG=<arg>] +---------------------------------------------------- + +This target runs the Python script given by the SCRIPT parameter on the +configuration. sys.argv[1] holds the name of the top-level Kconfig file +(currently always "Kconfig" in practice), and sys.argv[2] holds the SCRIPT_ARG +argument, if given. + +See the examples/ subdirectory for example scripts. + + +Using Kconfiglib without the Makefile targets +============================================= + +The make targets are only needed for a trivial reason: The Kbuild makefiles +export environment variables which are referenced inside the Kconfig files and +in scripts run from the Kconfig files (via e.g. 'source +"arch/$(SRCARCH)/Kconfig" and '$(shell,...)'). + +The environment variables referenced as of writing (Linux 4.2.18-rc4) are +srctree, ARCH, SRCARCH, CC, and KERNELVERSION. + +To run Kconfiglib without the Makefile patch, you can do this: + + $ srctree=. ARCH=x86 SRCARCH=x86 CC=gcc KERNELVERSION=`make kernelversion` python(3) + >>> import kconfiglib + >>> kconf = kconfiglib.Kconfig() # filename defaults to "Kconfig" + +Search the top-level Makefile for "Additional ARCH settings" to see other +possibilities for ARCH and SRCARCH. Kconfiglib will print a warning if an unset +environment variable is referenced inside the Kconfig files. + + +Intro to symbol values +====================== + +Kconfiglib has the same assignment semantics as the C implementation. + +Any symbol can be assigned a value by the user (via Kconfig.load_config() or +Symbol.set_value()), but this user value is only respected if the symbol is +visible, which corresponds to it (currently) being visible in the menuconfig +interface. + +For symbols with prompts, the visibility of the symbol is determined by the +condition on the prompt. Symbols without prompts are never visible, so setting +a user value on them is pointless. A warning will be printed by default if +Symbol.set_value() is called on a promptless symbol. Assignments to promptless +symbols are normal within a .config file, so no similar warning will be printed +by load_config(). + +Dependencies from parents and 'if'/'depends on' are propagated to properties, +including prompts, so these two configurations are logically equivalent: + +(1) + + menu "menu" + depends on A + + if B + + config FOO + tristate "foo" if D + default y + depends on C + + endif + + endmenu + +(2) + + menu "menu" + depends on A + + config FOO + tristate "foo" if A && B && C && D + default y if A && B && C + + endmenu + +In this example, A && B && C && D (the prompt condition) needs to be non-n for +FOO to be visible (assignable). If its value is m, the symbol can only be +assigned the value m: The visibility sets an upper bound on the value that can +be assigned by the user, and any higher user value will be truncated down. + +'default' properties are independent of the visibility, though a 'default' will +often get the same condition as the prompt due to dependency propagation. +'default' properties are used if the symbol is not visible or has no user +value. + +Symbols with no user value (or that have a user value but are not visible) and +no (active) 'default' default to n for bool/tristate symbols, and to the empty +string for other symbol types. + +'select' works similarly to symbol visibility, but sets a lower bound on the +value of the symbol. The lower bound is determined by the value of the +select*ing* symbol. 'select' does not respect visibility, so non-visible +symbols can be forced to a particular (minimum) value by a select as well. + +For non-bool/tristate symbols, it only matters whether the visibility is n or +non-n: m visibility acts the same as y visibility. + +Conditions on 'default' and 'select' work in mostly intuitive ways. If the +condition is n, the 'default' or 'select' is disabled. If it is m, the +'default' or 'select' value (the value of the selecting symbol) is truncated +down to m. + +When writing a configuration with Kconfig.write_config(), only symbols that are +visible, have an (active) default, or are selected will get written out (note +that this includes all symbols that would accept user values). Kconfiglib +matches the .config format produced by the C implementations down to the +character. This eases testing. + +For a visible bool/tristate symbol FOO with value n, this line is written to +.config: + + # CONFIG_FOO is not set + +The point is to remember the user n selection (which might differ from the +default value the symbol would get), while at the same sticking to the rule +that undefined corresponds to n (.config uses Makefile format, making the line +above a comment). When the .config file is read back in, this line will be +treated the same as the following assignment: + + CONFIG_FOO=n + +In Kconfiglib, the set of (currently) assignable values for a bool/tristate +symbol appear in Symbol.assignable. For other symbol types, just check if +sym.visibility is non-0 (non-n) to see whether the user value will have an +effect. + + +Intro to the menu tree +====================== + +The menu structure, as seen in e.g. menuconfig, is represented by a tree of +MenuNode objects. The top node of the configuration corresponds to an implicit +top-level menu, the title of which is shown at the top in the standard +menuconfig interface. (The title is also available in Kconfig.mainmenu_text in +Kconfiglib.) + +The top node is found in Kconfig.top_node. From there, you can visit child menu +nodes by following the 'list' pointer, and any following menu nodes by +following the 'next' pointer. Usually, a non-None 'list' pointer indicates a +menu or Choice, but menu nodes for symbols can sometimes have a non-None 'list' +pointer too due to submenus created implicitly from dependencies. + +MenuNode.item is either a Symbol or a Choice object, or one of the constants +MENU and COMMENT. The prompt of the menu node can be found in MenuNode.prompt, +which also holds the title for menus and comments. For Symbol and Choice, +MenuNode.help holds the help text (if any, otherwise None). + +Most symbols will only have a single menu node. A symbol defined in multiple +locations will have one menu node for each location. The list of menu nodes for +a Symbol or Choice can be found in the Symbol/Choice.nodes attribute. + +Note that prompts and help texts for symbols and choices are stored in their +menu node(s) rather than in the Symbol or Choice objects themselves. This makes +it possible to define a symbol in multiple locations with a different prompt or +help text in each location. To get the help text or prompt for a symbol with a +single menu node, do sym.nodes[0].help and sym.nodes[0].prompt, respectively. +The prompt is a (text, condition) tuple, where condition determines the +visibility (see 'Intro to expressions' below). + +This organization mirrors the C implementation. MenuNode is called +'struct menu' there, but I thought "menu" was a confusing name. + +It is possible to give a Choice a name and define it in multiple locations, +hence why Choice.nodes is also a list. + +As a convenience, the properties added at a particular definition location are +available on the MenuNode itself, in e.g. MenuNode.defaults. This is helpful +when generating documentation, so that symbols/choices defined in multiple +locations can be shown with the correct properties at each location. + + +Intro to expressions +==================== + +Expressions can be evaluated with the expr_value() function and printed with +the expr_str() function (these are used internally as well). Evaluating an +expression always yields a tristate value, where n, m, and y are represented as +0, 1, and 2, respectively. + +The following table should help you figure out how expressions are represented. +A, B, C, ... are symbols (Symbol instances), NOT is the kconfiglib.NOT +constant, etc. + +Expression Representation +---------- -------------- +A A +"A" A (constant symbol) +!A (NOT, A) +A && B (AND, A, B) +A && B && C (AND, A, (AND, B, C)) +A || B (OR, A, B) +A || (B && C && D) (OR, A, (AND, B, (AND, C, D))) +A = B (EQUAL, A, B) +A != "foo" (UNEQUAL, A, foo (constant symbol)) +A && B = C && D (AND, A, (AND, (EQUAL, B, C), D)) +n Kconfig.n (constant symbol) +m Kconfig.m (constant symbol) +y Kconfig.y (constant symbol) +"y" Kconfig.y (constant symbol) + +Strings like "foo" in 'default "foo"' or 'depends on SYM = "foo"' are +represented as constant symbols, so the only values that appear in expressions +are symbols***. This mirrors the C implementation. + +***For choice symbols, the parent Choice will appear in expressions as well, +but it's usually invisible as the value interfaces of Symbol and Choice are +identical. This mirrors the C implementation and makes different choice modes +"just work". + +Manual evaluation examples: + + - The value of A && B is min(A.tri_value, B.tri_value) + + - The value of A || B is max(A.tri_value, B.tri_value) + + - The value of !A is 2 - A.tri_value + + - The value of A = B is 2 (y) if A.str_value == B.str_value, and 0 (n) + otherwise. Note that str_value is used here instead of tri_value. + + For constant (as well as undefined) symbols, str_value matches the name of + the symbol. This mirrors the C implementation and explains why + 'depends on SYM = "foo"' above works as expected. + +n/m/y are automatically converted to the corresponding constant symbols +"n"/"m"/"y" (Kconfig.n/m/y) during parsing. + +Kconfig.const_syms is a dictionary like Kconfig.syms but for constant symbols. + +If a condition is missing (e.g., <cond> when the 'if <cond>' is removed from +'default A if <cond>'), it is actually Kconfig.y. The standard __str__() +functions just avoid printing 'if y' conditions to give cleaner output. + + +Kconfig extensions +================== + +Kconfiglib implements two Kconfig extensions related to 'source': + +'source' with relative path +--------------------------- + +The library implements a custom 'rsource' statement that allows to import +Kconfig file by specifying path relative to directory of the currently parsed +file, instead of path relative to project root. +This extension is not supported by Linux kernel tools (yet). + +Consider following directory tree: + + Project + +--Kconfig + | + +--src + +--Kconfig + | + +--SubSystem1 + +--Kconfig + | + +--ModuleA + +--Kconfig + +In above example, src/SubSystem1/Kconfig imports Kconfig for ModuleA. +With default 'source' it looks like: + + source "src/SubSystem1/ModuleA/Kconfig" + +Using 'rsource' it can be rewritten as: + + rsource "ModuleA/Kconfig" + +If absolute path is given to 'rsource' then it follows behavior of 'source'. + + +Globbed sourcing +---------------- + +'source' and 'rsource' accept glob patterns, sourcing all matching Kconfig +files. They require at least one matching file, throwing a KconfigError +otherwise. + +For example, the following statement might source sub1/foofoofoo and +sub2/foobarfoo: + + source "sub[12]/foo*foo" + +The glob patterns accepted are the same as for the standard glob.glob() +function. + +Two additional statements are provided for cases where it's acceptable for a +pattern to match no files: 'osource' and 'orsource' (the o is for "optional"). + +For example, the following statements will be no-ops if neither "foo" nor any +files matching "bar*" exist: + + osource "foo" + osource "bar*" + +'orsource' does a relative optional source. + +'source' and 'osource' are analogous to 'include' and '-include' in Make. + + +Feedback +======== + +Send bug reports, suggestions, and questions to ulfalizer a.t Google's email +service, or open a ticket on the GitHub page. +""" +import errno +import glob +import os +import platform +import re +import subprocess +import sys +import textwrap + +# File layout: +# +# Public classes +# Public functions +# Internal functions +# Public global constants +# Internal global constants + +# Line length: 79 columns + +# +# Public classes +# + +class Kconfig(object): + """ + Represents a Kconfig configuration, e.g. for x86 or ARM. This is the set of + symbols, choices, and menu nodes appearing in the configuration. Creating + any number of Kconfig objects (including for different architectures) is + safe. Kconfiglib doesn't keep any global state. + + The following attributes are available. They should be treated as + read-only, and some are implemented through @property magic. + + syms: + A dictionary with all symbols in the configuration, indexed by name. Also + includes all symbols that are referenced in expressions but never + defined, except for constant (quoted) symbols. + + Undefined symbols can be recognized by Symbol.nodes being empty -- see + the 'Intro to the menu tree' section in the module docstring. + + const_syms: + A dictionary like 'syms' for constant (quoted) symbols + + named_choices: + A dictionary like 'syms' for named choices (choice FOO) + + defined_syms: + A list with all defined symbols, in the same order as they appear in the + Kconfig files. Symbols defined in multiple locations appear multiple + times. Iterating over set(defined_syms) will visit each defined symbol + once. + + choices: + A list with all choices, in the same order as they appear in the Kconfig + files. Named choices defined in multiple locations appear multiple times. + Iterating over set(choices) will visit each choice once. + + menus: + A list with all menus, in the same order as they appear in the Kconfig + files + + comments: + A list with all comments, in the same order as they appear in the Kconfig + files + + n/m/y: + The predefined constant symbols n/m/y. Also available in const_syms. + + modules: + The Symbol instance for the modules symbol. Currently hardcoded to + MODULES, which is backwards compatible. Kconfiglib will warn if + 'option modules' is set on some other symbol. Tell me if you need proper + 'option modules' support. + + 'modules' is never None. If the MODULES symbol is not explicitly defined, + its tri_value will be 0 (n), as expected. + + A simple way to enable modules is to do 'kconf.modules.set_value(2)' + (provided the MODULES symbol is defined and visible). Modules are + disabled by default in the kernel Kconfig files as of writing, though + nearly all defconfig files enable them (with 'CONFIG_MODULES=y'). + + defconfig_list: + The Symbol instance for the 'option defconfig_list' symbol, or None if no + defconfig_list symbol exists. The defconfig filename derived from this + symbol can be found in Kconfig.defconfig_filename. + + defconfig_filename: + The filename given by the defconfig_list symbol. This is taken from the + first 'default' with a satisfied condition where the specified file + exists (can be opened for reading). If a defconfig file foo/defconfig is + not found and $srctree was set when the Kconfig was created, + $srctree/foo/defconfig is looked up as well. + + 'defconfig_filename' is None if either no defconfig_list symbol exists, + or if the defconfig_list symbol has no 'default' with a satisfied + condition that specifies a file that exists. + + Gotcha: scripts/kconfig/Makefile might pass --defconfig=<defconfig> to + scripts/kconfig/conf when running e.g. 'make defconfig'. This option + overrides the defconfig_list symbol, meaning defconfig_filename might not + always match what 'make defconfig' would use. + + top_node: + The menu node (see the MenuNode class) of the implicit top-level menu. + Acts as the root of the menu tree. + + mainmenu_text: + The prompt (title) of the top menu (top_node). Defaults to "Main menu". + Can be changed with the 'mainmenu' statement (see kconfig-language.txt). + + variables: + A dictionary with all preprocessor variables, indexed by name. See the + Variable class. + + warnings: + A list of strings containing all warnings that have been generated. This + allows flexibility in how warnings are printed and processed. + + See the 'warn_to_stderr' parameter to Kconfig.__init__() and the + Kconfig.enable/disable_stderr_warnings() functions as well. Note that + warnings still get added to Kconfig.warnings when 'warn_to_stderr' is + True. + + Just as for warnings printed to stderr, only optional warnings that are + enabled will get added to Kconfig.warnings. See the various + Kconfig.enable/disable_*_warnings() functions. + + srctree: + The value of the $srctree environment variable when the configuration was + loaded, or the empty string if $srctree wasn't set. This gives nice + behavior with os.path.join(), which treats "" as the current directory, + without adding "./". + + Kconfig files are looked up relative to $srctree (unless absolute paths + are used), and .config files are looked up relative to $srctree if they + are not found in the current directory. This is used to support + out-of-tree builds. The C tools use this environment variable in the same + way. + + Changing $srctree after creating the Kconfig instance has no effect. Only + the value when the configuration is loaded matters. This avoids surprises + if multiple configurations are loaded with different values for $srctree. + + config_prefix: + The value of the $CONFIG_ environment variable when the configuration was + loaded. This is the prefix used (and expected) on symbol names in .config + files and C headers. Defaults to "CONFIG_". Used in the same way in the C + tools. + + Like for srctree, only the value of $CONFIG_ when the configuration is + loaded matters. + """ + __slots__ = ( + "_defined_syms_set", + "_encoding", + "_functions", + "_set_match", + "_unset_match", + "_warn_for_no_prompt", + "_warn_for_redun_assign", + "_warn_for_undef_assign", + "_warn_to_stderr", + "_warnings_enabled", + "choices", + "comments", + "config_prefix", + "const_syms", + "defconfig_list", + "defined_syms", + "m", + "mainmenu_text", + "menus", + "modules", + "n", + "named_choices", + "srctree", + "syms", + "top_node", + "variables", + "warnings", + "y", + + # Parsing-related + "_parsing_kconfigs", + "_file", + "_filename", + "_linenr", + "_filestack", + "_line", + "_saved_line", + "_tokens", + "_tokens_i", + "_has_tokens", + ) + + # + # Public interface + # + + def __init__(self, filename="Kconfig", warn=True, warn_to_stderr=True, + encoding="utf-8"): + """ + Creates a new Kconfig object by parsing Kconfig files. Raises + KconfigError on syntax errors. Note that Kconfig files are not the same + as .config files (which store configuration symbol values). + + If the environment variable KCONFIG_STRICT is set to "y", warnings will + be generated for all references to undefined symbols within Kconfig + files. The reason this isn't the default is that some projects (e.g. + the Linux kernel) use multiple Kconfig trees (one per architecture) + with many shared Kconfig files, leading to some safe references to + undefined symbols. + + KCONFIG_STRICT relies on literal hex values being prefixed with 0x/0X. + They are indistinguishable from references to undefined symbols + otherwise. + + KCONFIG_STRICT might enable other warnings that depend on there being + just a single Kconfig tree in the future. + + filename (default: "Kconfig"): + The Kconfig file to load. For the Linux kernel, you'll want "Kconfig" + from the top-level directory, as environment variables will make sure + the right Kconfig is included from there (arch/$SRCARCH/Kconfig as of + writing). + + If you are using Kconfiglib via 'make scriptconfig', the filename of + the base base Kconfig file will be in sys.argv[1]. It's currently + always "Kconfig" in practice. + + The $srctree environment variable is used to look up Kconfig files + referenced in Kconfig files if set. See the class documentation. + + Note: '(o)source' statements in Kconfig files always work relative to + $srctree (or the current directory if $srctree is unset), even if + 'filename' is a path with directories. This allows a subset of + Kconfig files to be loaded without breaking references to other + Kconfig files, e.g. by doing Kconfig("./sub/Kconfig"). sub/Kconfig + might expect to be sourced by ./Kconfig. + + warn (default: True): + True if warnings related to this configuration should be generated. + This can be changed later with Kconfig.enable/disable_warnings(). It + is provided as a constructor argument since warnings might be + generated during parsing. + + See the other Kconfig.enable_*_warnings() functions as well, which + enable or suppress certain warnings when warnings are enabled. + + All generated warnings are added to the Kconfig.warnings list. See + the class documentation. + + warn_to_stderr (default: True): + True if warnings should be printed to stderr in addition to being + added to Kconfig.warnings. + + This can be changed later with + Kconfig.enable/disable_stderr_warnings(). + + encoding (default: "utf-8"): + The encoding to use when reading and writing files. If None, the + encoding specified in the current locale will be used. + + The "utf-8" default avoids exceptions on systems that are configured + to use the C locale, which implies an ASCII encoding. + + This parameter has no effect on Python 2, due to implementation + issues (regular strings turning into Unicode strings, which are + distinct in Python 2). Python 2 doesn't decode regular strings + anyway. + + Related PEP: https://www.python.org/dev/peps/pep-0538/ + """ + self.srctree = os.environ.get("srctree", "") + self.config_prefix = os.environ.get("CONFIG_", "CONFIG_") + + # Regular expressions for parsing .config files + self._set_match = _re_match(self.config_prefix + r"([^=]+)=(.*)") + self._unset_match = \ + _re_match(r"# {}([^ ]+) is not set".format(self.config_prefix)) + + + self.warnings = [] + + self._warnings_enabled = warn + self._warn_to_stderr = warn_to_stderr + self._warn_for_undef_assign = False + self._warn_for_redun_assign = True + + + self._encoding = encoding + + + self.syms = {} + self.const_syms = {} + self.defined_syms = [] + + self.named_choices = {} + self.choices = [] + + self.menus = [] + self.comments = [] + + for nmy in "n", "m", "y": + sym = Symbol() + sym.kconfig = self + sym.name = nmy + sym.is_constant = True + sym.orig_type = TRISTATE + sym._cached_tri_val = STR_TO_TRI[nmy] + + self.const_syms[nmy] = sym + + self.n = self.const_syms["n"] + self.m = self.const_syms["m"] + self.y = self.const_syms["y"] + + # Make n/m/y well-formed symbols + for nmy in "n", "m", "y": + sym = self.const_syms[nmy] + sym.rev_dep = sym.weak_rev_dep = sym.direct_dep = self.n + + + # Maps preprocessor variables names to Variable instances + self.variables = {} + + # Predefined preprocessor functions, with min/max number of arguments + self._functions = { + "info": (_info_fn, 1, 1), + "error-if": (_error_if_fn, 2, 2), + "filename": (_filename_fn, 0, 0), + "lineno": (_lineno_fn, 0, 0), + "shell": (_shell_fn, 1, 1), + "warning-if": (_warning_if_fn, 2, 2), + } + + + # This is used to determine whether previously unseen symbols should be + # registered. They shouldn't be if we parse expressions after parsing, + # as part of Kconfig.eval_string(). + self._parsing_kconfigs = True + + self.modules = self._lookup_sym("MODULES") + self.defconfig_list = None + + self.top_node = MenuNode() + self.top_node.kconfig = self + self.top_node.item = MENU + self.top_node.is_menuconfig = True + self.top_node.visibility = self.y + self.top_node.prompt = ("Main menu", self.y) + self.top_node.parent = None + self.top_node.dep = self.y + self.top_node.filename = os.path.relpath(filename, self.srctree) + self.top_node.linenr = 1 + + # Parse the Kconfig files + + # These implement a single line of "unget" for the parser + self._saved_line = None + self._has_tokens = False + + # Keeps track of the location in the parent Kconfig files. Kconfig + # files usually source other Kconfig files. + self._filestack = [] + + # The current parsing location + self._filename = os.path.relpath(filename, self.srctree) + self._linenr = 0 + + # Open the top-level Kconfig file + self._file = self._open(filename, "r") + + try: + # Parse everything + self._parse_block(None, self.top_node, self.top_node) + except UnicodeDecodeError as e: + _decoding_error(e, self._filename) + + self.top_node.list = self.top_node.next + self.top_node.next = None + + # Projects like U-Boot and Zephyr make heavy use of being able to + # define a symbol in multiple locations. Removing duplicates makes a + # massive difference for U-Boot, speeding up parsing from ~4 seconds to + # ~0.6 seconds on my machine. + self._defined_syms_set = set(self.defined_syms) + + self._parsing_kconfigs = False + + # Do various post-processing of the menu tree + self._finalize_tree(self.top_node, self.y) + + + # Do sanity checks. Some of these depend on everything being + # finalized. + + for sym in self._defined_syms_set: + _check_sym_sanity(sym) + + for choice in self.choices: + _check_choice_sanity(choice) + + if os.environ.get("KCONFIG_STRICT") == "y": + self._check_undefined_syms() + + + # Build Symbol._dependents for all symbols and choices + self._build_dep() + + # Check for dependency loops + for sym in self._defined_syms_set: + _check_dep_loop_sym(sym, False) + + # Add extra dependencies from choices to choice symbols that get + # awkward during dependency loop detection + self._add_choice_deps() + + + self._warn_for_no_prompt = True + + self.mainmenu_text = self.top_node.prompt[0] + + @property + def defconfig_filename(self): + """ + See the class documentation. + """ + if self.defconfig_list: + for filename, cond in self.defconfig_list.defaults: + if expr_value(cond): + try: + with self._open_config(filename.str_value) as f: + return f.name + except IOError: + continue + + return None + + def load_config(self, filename, replace=True): + """ + Loads symbol values from a file in the .config format. Equivalent to + calling Symbol.set_value() to set each of the values. + + "# CONFIG_FOO is not set" within a .config file sets the user value of + FOO to n. The C tools work the same way. + + The Symbol.user_value attribute can be inspected afterwards to see what + value the symbol was assigned in the .config file (if any). The user + value might differ from Symbol.str/tri_value if there are unsatisfied + dependencies. + + filename: + The file to load. Respects $srctree if set (see the class + documentation). + + replace (default: True): + True if all existing user values should be cleared before loading the + .config. + """ + # Disable the warning about assigning to symbols without prompts. This + # is normal and expected within a .config file. + self._warn_for_no_prompt = False + + # This stub only exists to make sure _warn_for_no_prompt gets reenabled + try: + self._load_config(filename, replace) + except UnicodeDecodeError as e: + _decoding_error(e, filename) + finally: + self._warn_for_no_prompt = True + + def _load_config(self, filename, replace): + with self._open_config(filename) as f: + if replace: + # If we're replacing the configuration, keep track of which + # symbols and choices got set so that we can unset the rest + # later. This avoids invalidating everything and is faster. + # Another benefit is that invalidation must be rock solid for + # it to work, making it a good test. + + for sym in self._defined_syms_set: + sym._was_set = False + + for choice in self.choices: + choice._was_set = False + + # Small optimizations + set_match = self._set_match + unset_match = self._unset_match + syms = self.syms + + for linenr, line in enumerate(f, 1): + # The C tools ignore trailing whitespace + line = line.rstrip() + + match = set_match(line) + if match: + name, val = match.groups() + if name not in syms: + self._warn_undef_assign_load(name, val, filename, + linenr) + continue + + sym = syms[name] + if not sym.nodes: + self._warn_undef_assign_load(name, val, filename, + linenr) + continue + + if sym.orig_type in (BOOL, TRISTATE): + # The C implementation only checks the first character + # to the right of '=', for whatever reason + if not ((sym.orig_type == BOOL and + val.startswith(("n", "y"))) or \ + (sym.orig_type == TRISTATE and + val.startswith(("n", "m", "y")))): + self._warn("'{}' is not a valid value for the {} " + "symbol {}. Assignment ignored." + .format(val, TYPE_TO_STR[sym.orig_type], + _name_and_loc(sym)), + filename, linenr) + continue + + val = val[0] + + if sym.choice and val != "n": + # During .config loading, we infer the mode of the + # choice from the kind of values that are assigned + # to the choice symbols + + prev_mode = sym.choice.user_value + if prev_mode is not None and \ + TRI_TO_STR[prev_mode] != val: + + self._warn("both m and y assigned to symbols " + "within the same choice", + filename, linenr) + + # Set the choice's mode + sym.choice.set_value(val) + + elif sym.orig_type == STRING: + match = _conf_string_match(val) + if not match: + self._warn("malformed string literal in " + "assignment to {}. Assignment ignored." + .format(_name_and_loc(sym)), + filename, linenr) + continue + + val = unescape(match.group(1)) + + else: + match = unset_match(line) + if not match: + # Print a warning for lines that match neither + # set_match() nor unset_match() and that are not blank + # lines or comments. 'line' has already been + # rstrip()'d, so blank lines show up as "" here. + if line and not line.lstrip().startswith("#"): + self._warn("ignoring malformed line '{}'" + .format(line), + filename, linenr) + + continue + + name = match.group(1) + if name not in syms: + self._warn_undef_assign_load(name, "n", filename, + linenr) + continue + + sym = syms[name] + if sym.orig_type not in (BOOL, TRISTATE): + continue + + val = "n" + + # Done parsing the assignment. Set the value. + + if sym._was_set: + # Use strings for bool/tristate user values in the warning + if sym.orig_type in (BOOL, TRISTATE): + display_user_val = TRI_TO_STR[sym.user_value] + else: + display_user_val = sym.user_value + + warn_msg = '{} set more than once. Old value: "{}", new value: "{}".'.format( + _name_and_loc(sym), display_user_val, val + ) + + if display_user_val == val: + self._warn_redun_assign(warn_msg, filename, linenr) + else: + self._warn( warn_msg, filename, linenr) + + sym.set_value(val) + + if replace: + # If we're replacing the configuration, unset the symbols that + # didn't get set + + for sym in self._defined_syms_set: + if not sym._was_set: + sym.unset_value() + + for choice in self.choices: + if not choice._was_set: + choice.unset_value() + + def write_autoconf(self, filename, + header="/* Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib) */\n"): + r""" + Writes out symbol values as a C header file, matching the format used + by include/generated/autoconf.h in the kernel. + + The ordering of the #defines matches the one generated by + write_config(). The order in the C implementation depends on the hash + table implementation as of writing, and so won't match. + + filename: + Self-explanatory. + + header (default: "/* Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib) */\n"): + Text that will be inserted verbatim at the beginning of the file. You + would usually want it enclosed in '/* */' to make it a C comment, + and include a final terminating newline. + """ + with self._open(filename, "w") as f: + f.write(header) + + # Avoid duplicates -- see write_config() + for sym in self._defined_syms_set: + sym._written = False + + for sym in self._defined_syms_set: + if not sym._written: + sym._written = True + # Note: _write_to_conf is determined when the value is + # calculated. This is a hidden function call due to + # property magic. + val = sym.str_value + if sym._write_to_conf: + if sym.orig_type in (BOOL, TRISTATE): + if val != "n": + f.write("#define {}{}{} 1\n" + .format(self.config_prefix, sym.name, + "_MODULE" if val == "m" else "")) + + elif sym.orig_type == STRING: + f.write('#define {}{} "{}"\n' + .format(self.config_prefix, sym.name, + escape(val))) + + elif sym.orig_type in (INT, HEX): + if sym.orig_type == HEX and \ + not val.startswith(("0x", "0X")): + val = "0x" + val + + f.write("#define {}{} {}\n" + .format(self.config_prefix, sym.name, val)) + + else: + _internal_error("Internal error while creating C " + 'header: unknown type "{}".' + .format(sym.orig_type)) + + def write_config(self, filename, + header="# Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib)\n"): + r""" + Writes out symbol values in the .config format. The format matches the + C implementation, including ordering. + + Symbols appear in the same order in generated .config files as they do + in the Kconfig files. For symbols defined in multiple locations, a + single assignment is written out corresponding to the first location + where the symbol is defined. + + See the 'Intro to symbol values' section in the module docstring to + understand which symbols get written out. + + filename: + Self-explanatory. + + header (default: "# Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib)\n"): + Text that will be inserted verbatim at the beginning of the file. You + would usually want each line to start with '#' to make it a comment, + and include a final terminating newline. + """ + with self._open(filename, "w") as f: + f.write(header) + + # Symbol._written is set to True when a symbol config string is + # fetched, so that symbols defined in multiple locations only get + # one .config entry. We reset it prior to writing out a new + # .config. It only needs to be reset for defined symbols, because + # undefined symbols will never be written out (because they do not + # appear in the menu tree rooted at Kconfig.top_node). + # + # The C tools reuse _write_to_conf for this, but we cache + # _write_to_conf together with the value and don't invalidate + # cached values when writing .config files, so that won't work. + for sym in self._defined_syms_set: + sym._written = False + + node = self.top_node.list + if not node: + # Empty configuration + return + + while 1: + item = node.item + if isinstance(item, Symbol): + if not item._written: + item._written = True + f.write(item.config_string) + + elif expr_value(node.dep) and \ + ((item == MENU and expr_value(node.visibility)) or + item == COMMENT): + + f.write("\n#\n# {}\n#\n".format(node.prompt[0])) + + # Iterative tree walk using parent pointers + + if node.list: + node = node.list + elif node.next: + node = node.next + else: + while node.parent: + node = node.parent + if node.next: + node = node.next + break + else: + return + + def write_min_config(self, filename, + header="# Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib)\n"): + """ + Writes out a "minimal" configuration file, omitting symbols whose value + matches their default value. The format matches the one produced by + 'make savedefconfig'. + + The resulting configuration file is incomplete, but a complete + configuration can be derived from it by loading it. Minimal + configuration files can serve as a more manageable configuration format + compared to a "full" .config file, especially when configurations files + are merged or edited by hand. + + filename: + Self-explanatory. + + header (default: "# Generated by Kconfiglib (https://github.com/ulfalizer/Kconfiglib)\n"): + Text that will be inserted verbatim at the beginning of the file. You + would usually want each line to start with '#' to make it a comment, + and include a final terminating newline. + """ + with self._open(filename, "w") as f: + f.write(header) + + # Avoid duplicates -- see write_config() + for sym in self._defined_syms_set: + sym._written = False + + for sym in self._defined_syms_set: + if not sym._written: + sym._written = True + + # Skip symbols that cannot be changed. Only check + # non-choice symbols, as selects don't affect choice + # symbols. + if not sym.choice and \ + sym.visibility <= expr_value(sym.rev_dep): + continue + + # Skip symbols whose value matches their default + if sym.str_value == sym._str_default(): + continue + + # Skip symbols that would be selected by default in a + # choice, unless the choice is optional or the symbol type + # isn't bool (it might be possible to set the choice mode + # to n or the symbol to m in those cases). + if sym.choice and \ + not sym.choice.is_optional and \ + sym.choice._get_selection_from_defaults() is sym and \ + sym.orig_type == BOOL and \ + sym.tri_value == 2: + continue + + f.write(sym.config_string) + + def sync_deps(self, path): + """ + Creates or updates a directory structure that can be used to avoid + doing a full rebuild whenever the configuration is changed, mirroring + include/config/ in the kernel. + + This function is intended to be called during each build, before + compiling source files that depend on configuration symbols. + + path: + Path to directory + + sync_deps(path) does the following: + + 1. If the directory <path> does not exist, it is created. + + 2. If <path>/auto.conf exists, old symbol values are loaded from it, + which are then compared against the current symbol values. If a + symbol has changed value (would generate different output in + autoconf.h compared to before), the change is signaled by + touch'ing a file corresponding to the symbol. + + The first time sync_deps() is run on a directory, <path>/auto.conf + won't exist, and no old symbol values will be available. This + logically has the same effect as updating the entire + configuration. + + The path to a symbol's file is calculated from the symbol's name + by replacing all '_' with '/' and appending '.h'. For example, the + symbol FOO_BAR_BAZ gets the file <path>/foo/bar/baz.h, and FOO + gets the file <path>/foo.h. + + This scheme matches the C tools. The point is to avoid having a + single directory with a huge number of files, which the underlying + filesystem might not handle well. + + 3. A new auto.conf with the current symbol values is written, to keep + track of them for the next build. + + + The last piece of the puzzle is knowing what symbols each source file + depends on. Knowing that, dependencies can be added from source files + to the files corresponding to the symbols they depends on. The source + file will then get recompiled (only) when the symbol value changes + (provided sync_deps() is run first during each build). + + The tool in the kernel that extracts symbol dependencies from source + files is scripts/basic/fixdep.c. Missing symbol files also correspond + to "not changed", which fixdep deals with by using the $(wildcard) Make + function when adding symbol prerequisites to source files. + + In case you need a different scheme for your project, the sync_deps() + implementation can be used as a template.""" + if not os.path.exists(path): + os.mkdir(path, 0o755) + + # This setup makes sure that at least the current working directory + # gets reset if things fail + prev_dir = os.getcwd() + try: + # cd'ing into the symbol file directory simplifies + # _sync_deps() and saves some work + os.chdir(path) + self._sync_deps() + finally: + os.chdir(prev_dir) + + def _sync_deps(self): + # Load old values from auto.conf, if any + self._load_old_vals() + + for sym in self._defined_syms_set: + # Note: _write_to_conf is determined when the value is + # calculated. This is a hidden function call due to + # property magic. + val = sym.str_value + + # Note: n tristate values do not get written to auto.conf and + # autoconf.h, making a missing symbol logically equivalent to n + + if sym._write_to_conf: + if sym._old_val is None and \ + sym.orig_type in (BOOL, TRISTATE) and \ + val == "n": + # No old value (the symbol was missing or n), new value n. + # No change. + continue + + if val == sym._old_val: + # New value matches old. No change. + continue + + elif sym._old_val is None: + # The symbol wouldn't appear in autoconf.h (because + # _write_to_conf is false), and it wouldn't have appeared in + # autoconf.h previously either (because it didn't appear in + # auto.conf). No change. + continue + + # 'sym' has a new value. Flag it. + + sym_path = sym.name.lower().replace("_", os.sep) + ".h" + sym_path_dir = os.path.dirname(sym_path) + if sym_path_dir and not os.path.exists(sym_path_dir): + os.makedirs(sym_path_dir, 0o755) + + # A kind of truncating touch, mirroring the C tools + os.close(os.open( + sym_path, os.O_WRONLY | os.O_CREAT | os.O_TRUNC, 0o644)) + + # Remember the current values as the "new old" values. + # + # This call could go anywhere after the call to _load_old_vals(), but + # putting it last means _sync_deps() can be safely rerun if it fails + # before this point. + self._write_old_vals() + + def _write_old_vals(self): + # Helper for writing auto.conf. Basically just a simplified + # write_config() that doesn't write any comments (including + # '# CONFIG_FOO is not set' comments). The format matches the C + # implementation, though the ordering is arbitrary there (depends on + # the hash table implementation). + # + # A separate helper function is neater than complicating write_config() + # by passing a flag to it, plus we only need to look at symbols here. + + with self._open("auto.conf", "w") as f: + for sym in self._defined_syms_set: + sym._written = False + + for sym in self._defined_syms_set: + if not sym._written: + sym._written = True + if not (sym.orig_type in (BOOL, TRISTATE) and + not sym.tri_value): + f.write(sym.config_string) + + def _load_old_vals(self): + # Loads old symbol values from auto.conf into a dedicated + # Symbol._old_val field. Mirrors load_config(). + # + # The extra field could be avoided with some trickery involving dumping + # symbol values and restoring them later, but this is simpler and + # faster. The C tools also use a dedicated field for this purpose. + + for sym in self._defined_syms_set: + sym._old_val = None + + if not os.path.exists("auto.conf"): + # No old values + return + + with self._open("auto.conf", "r") as f: + for line in f: + match = self._set_match(line) + if not match: + # We only expect CONFIG_FOO=... (and possibly a header + # comment) in auto.conf + continue + + name, val = match.groups() + if name in self.syms: + sym = self.syms[name] + + if sym.orig_type == STRING: + match = _conf_string_match(val) + if not match: + continue + val = unescape(match.group(1)) + + self.syms[name]._old_val = val + + def eval_string(self, s): + """ + Returns the tristate value of the expression 's', represented as 0, 1, + and 2 for n, m, and y, respectively. Raises KconfigError if syntax + errors are detected in 's'. Warns if undefined symbols are referenced. + + As an example, if FOO and BAR are tristate symbols at least one of + which has the value y, then config.eval_string("y && (FOO || BAR)") + returns 2 (y). + + To get the string value of non-bool/tristate symbols, use + Symbol.str_value. eval_string() always returns a tristate value, and + all non-bool/tristate symbols have the tristate value 0 (n). + + The expression parsing is consistent with how parsing works for + conditional ('if ...') expressions in the configuration, and matches + the C implementation. m is rewritten to 'm && MODULES', so + eval_string("m") will return 0 (n) unless modules are enabled. + """ + # The parser is optimized to be fast when parsing Kconfig files (where + # an expression can never appear at the beginning of a line). We have + # to monkey-patch things a bit here to reuse it. + + self._filename = None + + # Don't include the "if " from below to avoid giving confusing error + # messages + self._line = s + # Remove the _T_IF token + self._tokens = self._tokenize("if " + s)[1:] + self._tokens_i = -1 + + return expr_value(self._parse_expr(True)) # transform_m + + def unset_values(self): + """ + Resets the user values of all symbols, as if Kconfig.load_config() or + Symbol.set_value() had never been called. + """ + self._warn_for_no_prompt = False + try: + # set_value() already rejects undefined symbols, and they don't + # need to be invalidated (because their value never changes), so we + # can just iterate over defined symbols + for sym in self._defined_syms_set: + sym.unset_value() + + for choice in self.choices: + choice.unset_value() + finally: + self._warn_for_no_prompt = True + + def enable_warnings(self): + """ + See Kconfig.__init__(). + """ + self._warnings_enabled = True + + def disable_warnings(self): + """ + See Kconfig.__init__(). + """ + self._warnings_enabled = False + + def enable_stderr_warnings(self): + """ + See Kconfig.__init__(). + """ + self._warn_to_stderr = True + + def disable_stderr_warnings(self): + """ + See Kconfig.__init__(). + """ + self._warn_to_stderr = False + + def enable_undef_warnings(self): + """ + Enables warnings for assignments to undefined symbols. Disabled by + default since they tend to be spammy for Kernel configurations (and + mostly suggests cleanups). + """ + self._warn_for_undef_assign = True + + def disable_undef_warnings(self): + """ + See enable_undef_assign(). + """ + self._warn_for_undef_assign = False + + def enable_redun_warnings(self): + """ + Enables warnings for duplicated assignments in .config files that all + set the same value. + + These warnings are enabled by default. Disabling them might be helpful + in certain cases when merging configurations. + """ + self._warn_for_redun_assign = True + + def disable_redun_warnings(self): + """ + See enable_redun_warnings(). + """ + self._warn_for_redun_assign = False + + def __repr__(self): + """ + Returns a string with information about the Kconfig object when it is + evaluated on e.g. the interactive Python prompt. + """ + return "<{}>".format(", ".join(( + "configuration with {} symbols".format(len(self.syms)), + 'main menu prompt "{}"'.format(self.mainmenu_text), + "srctree is current directory" if not self.srctree else + 'srctree "{}"'.format(self.srctree), + 'config symbol prefix "{}"'.format(self.config_prefix), + "warnings " + + ("enabled" if self._warnings_enabled else "disabled"), + "printing of warnings to stderr " + + ("enabled" if self._warn_to_stderr else "disabled"), + "undef. symbol assignment warnings " + + ("enabled" if self._warn_for_undef_assign else "disabled"), + "redundant symbol assignment warnings " + + ("enabled" if self._warn_for_redun_assign else "disabled") + ))) + + # + # Private methods + # + + + # + # File reading + # + + def _open_config(self, filename): + # Opens a .config file. First tries to open 'filename', then + # '$srctree/filename' if $srctree was set when the configuration was + # loaded. + + try: + return self._open(filename, "r") + except IOError as e: + # This will try opening the same file twice if $srctree is unset, + # but it's not a big deal + try: + return self._open(os.path.join(self.srctree, filename), "r") + except IOError as e2: + # This is needed for Python 3, because e2 is deleted after + # the try block: + # + # https://docs.python.org/3/reference/compound_stmts.html#the-try-statement + e = e2 + + raise IOError("\n" + textwrap.fill( + "Could not open '{}' ({}: {}){}".format( + filename, errno.errorcode[e.errno], e.strerror, + self._srctree_hint()), + 80)) + + def _enter_file(self, full_filename, rel_filename): + # Jumps to the beginning of a sourced Kconfig file, saving the previous + # position and file object. + # + # full_filename: + # Actual path to the file. + # + # rel_filename: + # File path with $srctree prefix stripped, stored in e.g. + # self._filename (which makes it indirectly show up in + # MenuNode.filename). Equals full_filename for absolute paths. + + self._filestack.append((self._filename, self._linenr, self._file)) + + # Check for recursive 'source' + for name, _, _ in self._filestack: + if name == rel_filename: + raise KconfigError( + "\n{}:{}: Recursive 'source' of '{}' detected. Check that " + "environment variables are set correctly.\n" + "Backtrace:\n{}" + .format(self._filename, self._linenr, filename, + "\n".join("{}:{}".format(name, linenr) + for name, linenr, _ + in reversed(self._filestack)))) + + # Note: We already know that the file exists + + try: + self._file = self._open(full_filename, "r") + except IOError as e: + raise IOError("{}:{}: Could not open '{}' ({}: {})".format( + self._filename, self._linenr, full_filename, + errno.errorcode[e.errno], e.strerror)) + + self._filename = rel_filename + self._linenr = 0 + + def _leave_file(self): + # Returns from a Kconfig file to the file that sourced it + + self._file.close() + self._filename, self._linenr, self._file = self._filestack.pop() + + def _next_line(self): + # Fetches and tokenizes the next line from the current Kconfig file. + # Returns False at EOF and True otherwise. + + # _saved_line provides a single line of "unget", currently only used + # for help texts. + # + # This also works as expected if _saved_line is "", indicating EOF: + # "" is falsy, and readline() returns "" over and over at EOF. + if self._saved_line: + self._line = self._saved_line + self._saved_line = None + else: + self._line = self._file.readline() + if not self._line: + return False + self._linenr += 1 + + # Handle line joining + while self._line.endswith("\\\n"): + self._line = self._line[:-2] + self._file.readline() + self._linenr += 1 + + self._tokens = self._tokenize(self._line) + self._tokens_i = -1 # Token index (minus one) + + return True + + + # + # Tokenization + # + + def _lookup_sym(self, name): + # Fetches the symbol 'name' from the symbol table, creating and + # registering it if it does not exist. If '_parsing_kconfigs' is False, + # it means we're in eval_string(), and new symbols won't be registered. + + if name in self.syms: + return self.syms[name] + + sym = Symbol() + sym.kconfig = self + sym.name = name + sym.is_constant = False + sym.rev_dep = sym.weak_rev_dep = sym.direct_dep = self.n + + if self._parsing_kconfigs: + self.syms[name] = sym + else: + self._warn("no symbol {} in configuration".format(name)) + + return sym + + def _lookup_const_sym(self, name): + # Like _lookup_sym(), for constant (quoted) symbols + + if name in self.const_syms: + return self.const_syms[name] + + sym = Symbol() + sym.kconfig = self + sym.name = name + sym.is_constant = True + sym.rev_dep = sym.weak_rev_dep = sym.direct_dep = self.n + + if self._parsing_kconfigs: + self.const_syms[name] = sym + + return sym + + def _tokenize(self, s): + # Parses 's', returning a None-terminated list of tokens. Registers any + # new symbols encountered with _lookup(_const)_sym(). + # + # Tries to be reasonably speedy by processing chunks of text via + # regexes and string operations where possible. This is the biggest + # hotspot during parsing. + # + # Note: It might be possible to rewrite this to 'yield' tokens instead, + # working across multiple lines. The 'option env' lookback thing below + # complicates things though. + + # Initial token on the line + match = _command_match(s) + if not match: + if s.isspace() or s.lstrip().startswith("#"): + return (None,) + self._parse_error("unknown token at start of line") + + # Tricky implementation detail: While parsing a token, 'token' refers + # to the previous token. See _STRING_LEX for why this is needed. + token = _get_keyword(match.group(1)) + if not token: + # Backwards compatibility with old versions of the C tools, which + # (accidentally) accepted stuff like "--help--" and "-help---". + # This was fixed in the C tools by commit c2264564 ("kconfig: warn + # of unhandled characters in Kconfig commands"), committed in July + # 2015, but it seems people still run Kconfiglib on older kernels. + if s.strip(" \t\n-") == "help": + return (_T_HELP, None) + + # If the first token is not a keyword (and not a weird help token), + # we have a preprocessor variable assignment (or a bare macro on a + # line) + self._parse_assignment(s) + return (None,) + + tokens = [token] + # The current index in the string being tokenized + i = match.end() + + # Main tokenization loop (for tokens past the first one) + while i < len(s): + # Test for an identifier/keyword first. This is the most common + # case. + match = _id_keyword_match(s, i) + if match: + # We have an identifier or keyword + + # Jump past it + i = match.end() + + # Check what it is. lookup_sym() will take care of allocating + # new symbols for us the first time we see them. Note that + # 'token' still refers to the previous token. + + name = match.group(1) + keyword = _get_keyword(name) + if keyword: + # It's a keyword + token = keyword + + elif token not in _STRING_LEX: + # It's a non-const symbol, except we translate n, m, and y + # into the corresponding constant symbols, like the C + # implementation + token = self.const_syms[name] \ + if name in ("n", "m", "y") else \ + self._lookup_sym(name) + + else: + # It's a case of missing quotes. For example, the + # following is accepted: + # + # menu unquoted_title + # + # config A + # tristate unquoted_prompt + # + # endmenu + token = name + + else: + # Neither a keyword nor a non-const symbol (except + # $()-expansion might still yield a non-const symbol). + + # We always strip whitespace after tokens, so it is safe to + # assume that s[i] is the start of a token here. + c = s[i] + + if c in "\"'": + s, end_i = self._expand_str(s, i, c) + + # os.path.expandvars() and the $UNAME_RELEASE replace() is + # a backwards compatibility hack, which should be + # reasonably safe as expandvars() leaves references to + # undefined env. vars. as is. + # + # The preprocessor functionality changed how environment + # variables are referenced, to $(FOO). + val = os.path.expandvars( + s[i + 1:end_i - 1].replace("$UNAME_RELEASE", + platform.uname()[2])) + + i = end_i + + # This is the only place where we don't survive with a + # single token of lookback: 'option env="FOO"' does not + # refer to a constant symbol named "FOO". + token = val \ + if token in _STRING_LEX or \ + tokens[0] == _T_OPTION else \ + self._lookup_const_sym(val) + + elif s.startswith("&&", i): + token = _T_AND + i += 2 + + elif s.startswith("||", i): + token = _T_OR + i += 2 + + elif c == "=": + token = _T_EQUAL + i += 1 + + elif s.startswith("!=", i): + token = _T_UNEQUAL + i += 2 + + elif c == "!": + token = _T_NOT + i += 1 + + elif c == "(": + token = _T_OPEN_PAREN + i += 1 + + elif c == ")": + token = _T_CLOSE_PAREN + i += 1 + + elif s.startswith("$(", i): + s, end_i = self._expand_macro(s, i, ()) + val = s[i:end_i] + # isspace() is False for empty strings + if not val.strip(): + # Avoid creating a Kconfig symbol with a blank name. + # It's almost guaranteed to be an error. + self._parse_error("macro expanded to blank string") + i = end_i + + # Compatibility with what the C implementation does. Might + # be unexpected that you can reference non-constant symbols + # this way though... + token = self.const_syms[val] \ + if val in ("n", "m", "y") else \ + self._lookup_sym(val) + + elif c == "#": + break + + + # Very rare + + elif s.startswith("<=", i): + token = _T_LESS_EQUAL + i += 2 + + elif c == "<": + token = _T_LESS + i += 1 + + elif s.startswith(">=", i): + token = _T_GREATER_EQUAL + i += 2 + + elif c == ">": + token = _T_GREATER + i += 1 + + + else: + self._parse_error("unknown tokens in line") + + + # Skip trailing whitespace + while i < len(s) and s[i].isspace(): + i += 1 + + + # Add the token + tokens.append(token) + + # None-terminating the token list makes the token fetching functions + # simpler/faster + tokens.append(None) + + return tokens + + def _next_token(self): + self._tokens_i += 1 + return self._tokens[self._tokens_i] + + def _peek_token(self): + return self._tokens[self._tokens_i + 1] + + # The functions below are just _next_token() with extra syntax checking. + # Inlining _next_token() and _peek_token() into them saves a few % of + # parsing time. + # + # See the 'Intro to expressions' section for what a constant symbol is. + + def _expect_sym(self): + self._tokens_i += 1 + token = self._tokens[self._tokens_i] + + if not isinstance(token, Symbol): + self._parse_error("expected symbol") + + return token + + def _expect_nonconst_sym(self): + self._tokens_i += 1 + token = self._tokens[self._tokens_i] + + if not isinstance(token, Symbol) or token.is_constant: + self._parse_error("expected nonconstant symbol") + + return token + + def _expect_nonconst_sym_and_eol(self): + self._tokens_i += 1 + token = self._tokens[self._tokens_i] + + if not isinstance(token, Symbol) or token.is_constant: + self._parse_error("expected nonconstant symbol") + + if self._tokens[self._tokens_i + 1] is not None: + self._parse_error("extra tokens at end of line") + + return token + + def _expect_str(self): + self._tokens_i += 1 + token = self._tokens[self._tokens_i] + + if not isinstance(token, str): + self._parse_error("expected string") + + return token + + def _expect_str_and_eol(self): + self._tokens_i += 1 + token = self._tokens[self._tokens_i] + + if not isinstance(token, str): + self._parse_error("expected string") + + if self._tokens[self._tokens_i + 1] is not None: + self._parse_error("extra tokens at end of line") + + return token + + def _check_token(self, token): + # If the next token is 'token', removes it and returns True + + if self._tokens[self._tokens_i + 1] == token: + self._tokens_i += 1 + return True + return False + + + # + # Preprocessor logic + # + + def _parse_assignment(self, s): + # Parses a preprocessor variable assignment, registering the variable + # if it doesn't already exist. Also takes care of bare macros on lines + # (which are allowed, and can be useful for their side effects). + + # Expand any macros in the left-hand side of the assignment (the + # variable name) + s = s.lstrip() + i = 0 + while 1: + i = _assignment_lhs_fragment_match(s, i).end() + if s.startswith("$(", i): + s, i = self._expand_macro(s, i, ()) + else: + break + + if s.isspace(): + # We also accept a bare macro on a line (e.g. + # $(warning-if,$(foo),ops)), provided it expands to a blank string + return + + # Assigned variable + name = s[:i] + + + # Extract assignment operator (=, :=, or +=) and value + rhs_match = _assignment_rhs_match(s, i) + if not rhs_match: + self._parse_error("syntax error") + + op, val = rhs_match.groups() + + + if name in self.variables: + # Already seen variable + var = self.variables[name] + else: + # New variable + var = Variable() + var.kconfig = self + var.name = name + var._n_expansions = 0 + self.variables[name] = var + + # += acts like = on undefined variables (defines a recursive + # variable) + if op == "+=": + op = "=" + + if op == "=": + var.is_recursive = True + var.value = val + elif op == ":=": + var.is_recursive = False + var.value = self._expand_whole(val, ()) + else: # op == "+=" + # += does immediate expansion if the variable was last set + # with := + var.value += " " + (val if var.is_recursive else \ + self._expand_whole(val, ())) + + def _expand_whole(self, s, args): + # Expands preprocessor macros in all of 's'. Used whenever we don't + # have to worry about delimiters. See _expand_macro() re. the 'args' + # parameter. + # + # Returns the expanded string. + + i = 0 + while 1: + i = s.find("$(", i) + if i == -1: + break + s, i = self._expand_macro(s, i, args) + return s + + def _expand_str(self, s, i, quote): + # Expands a quoted string starting at index 'i' in 's'. Handles both + # backslash escapes and macro expansion. + # + # Returns the expanded 's' (including the part before the string) and + # the index of the first character after the expanded string in 's'. + + i += 1 # Skip over initial "/' + while 1: + match = _string_special_search(s, i) + if not match: + self._parse_error("unterminated string") + + + if match.group() == quote: + # Found the end of the string + return (s, match.end()) + + elif match.group() == "\\": + # Replace '\x' with 'x'. 'i' ends up pointing to the character + # after 'x', which allows macros to be canceled with '\$(foo)'. + i = match.end() + s = s[:match.start()] + s[i:] + + elif match.group() == "$(": + # A macro call within the string + s, i = self._expand_macro(s, match.start(), ()) + + else: + # A ' quote within " quotes or vice versa + i += 1 + + def _expand_macro(self, s, i, args): + # Expands a macro starting at index 'i' in 's'. If this macro resulted + # from the expansion of another macro, 'args' holds the arguments + # passed to that macro. + # + # Returns the expanded 's' (including the part before the macro) and + # the index of the first character after the expanded macro in 's'. + + start = i + i += 2 # Skip over "$(" + + # Start of current macro argument + arg_start = i + + # Arguments of this macro call + new_args = [] + + while 1: + match = _macro_special_search(s, i) + if not match: + self._parse_error("missing end parenthesis in macro expansion") + + + if match.group() == ")": + # Found the end of the macro + + new_args.append(s[arg_start:match.start()]) + + prefix = s[:start] + + # $(1) is replaced by the first argument to the function, etc., + # provided at least that many arguments were passed + + try: + # Does the macro look like an integer, with a corresponding + # argument? If so, expand it to the value of the argument. + prefix += args[int(new_args[0])] + except (ValueError, IndexError): + # Regular variables are just functions without arguments, + # and also go through the function value path + prefix += self._fn_val(new_args) + + return (prefix + s[match.end():], + len(prefix)) + + elif match.group() == ",": + # Found the end of a macro argument + new_args.append(s[arg_start:match.start()]) + arg_start = i = match.end() + + else: # match.group() == "$(" + # A nested macro call within the macro + s, i = self._expand_macro(s, match.start(), args) + + def _fn_val(self, args): + # Returns the result of calling the function args[0] with the arguments + # args[1..len(args)-1]. Plain variables are treated as functions + # without arguments. + + fn = args[0] + + if fn in self.variables: + var = self.variables[fn] + + if len(args) == 1: + # Plain variable + if var._n_expansions: + self._parse_error("Preprocessor variable {} recursively " + "references itself".format(var.name)) + elif var._n_expansions > 100: + # Allow functions to call themselves, but guess that functions + # that are overly recursive are stuck + self._parse_error("Preprocessor function {} seems stuck " + "in infinite recursion".format(var.name)) + + var._n_expansions += 1 + res = self._expand_whole(self.variables[fn].value, args) + var._n_expansions -= 1 + return res + + if fn in self._functions: + # Built-in function + + py_fn, min_arg, max_arg = self._functions[fn] + + if not min_arg <= len(args) - 1 <= max_arg: + if min_arg == max_arg: + expected_args = min_arg + else: + expected_args = "{}-{}".format(min_arg, max_arg) + + raise KconfigError("{}:{}: bad number of arguments in call " + "to {}, expected {}, got {}" + .format(self._filename, self._linenr, fn, + expected_args, len(args) - 1)) + + return py_fn(self, args) + + # Environment variables are tried last + if fn in os.environ: + return os.environ[fn] + + return "" + + + # + # Parsing + # + + def _make_and(self, e1, e2): + # Constructs an AND (&&) expression. Performs trivial simplification. + + if e1 is self.y: + return e2 + + if e2 is self.y: + return e1 + + if e1 is self.n or e2 is self.n: + return self.n + + return (AND, e1, e2) + + def _make_or(self, e1, e2): + # Constructs an OR (||) expression. Performs trivial simplification. + + if e1 is self.n: + return e2 + + if e2 is self.n: + return e1 + + if e1 is self.y or e2 is self.y: + return self.y + + return (OR, e1, e2) + + def _parse_block(self, end_token, parent, prev): + # Parses a block, which is the contents of either a file or an if, + # menu, or choice statement. + # + # end_token: + # The token that ends the block, e.g. _T_ENDIF ("endif") for ifs. + # None for files. + # + # parent: + # The parent menu node, corresponding to a menu, Choice, or 'if'. + # 'if's are flattened after parsing. + # + # prev: + # The previous menu node. New nodes will be added after this one (by + # modifying their 'next' pointer). + # + # 'prev' is reused to parse a list of child menu nodes (for a menu or + # Choice): After parsing the children, the 'next' pointer is assigned + # to the 'list' pointer to "tilt up" the children above the node. + # + # Returns the final menu node in the block (or 'prev' if the block is + # empty). This allows chaining. + + # We might already have tokens from parsing a line to check if it's a + # property and discovering it isn't. self._has_tokens functions as a + # kind of "unget". + while self._has_tokens or self._next_line(): + self._has_tokens = False + + t0 = self._next_token() + if t0 is None: + continue + + if t0 in (_T_CONFIG, _T_MENUCONFIG): + # The tokenizer allocates Symbol objects for us + sym = self._expect_nonconst_sym_and_eol() + self.defined_syms.append(sym) + + node = MenuNode() + node.kconfig = self + node.item = sym + node.is_menuconfig = (t0 == _T_MENUCONFIG) + node.prompt = node.help = node.list = None + node.parent = parent + node.filename = self._filename + node.linenr = self._linenr + + sym.nodes.append(node) + + self._parse_properties(node) + + if node.is_menuconfig and not node.prompt: + self._warn("the menuconfig symbol {} has no prompt" + .format(_name_and_loc(node.item))) + + # Tricky Python semantics: This assign prev.next before prev + prev.next = prev = node + + elif t0 in (_T_SOURCE, _T_RSOURCE, _T_OSOURCE, _T_ORSOURCE): + pattern = self._expect_str_and_eol() + + # Check if the pattern is absolute and avoid stripping srctree + # from it below in that case. We must do the check before + # join()'ing, as srctree might be an absolute path. + isabs = os.path.isabs(pattern) + + if t0 in (_T_RSOURCE, _T_ORSOURCE): + # Relative source + pattern = os.path.join(os.path.dirname(self._filename), + pattern) + + # Sort the glob results to ensure a consistent ordering of + # Kconfig symbols, which indirectly ensures a consistent + # ordering in e.g. .config files + filenames = \ + sorted(glob.iglob(os.path.join(self.srctree, pattern))) + + if not filenames and t0 in (_T_SOURCE, _T_RSOURCE): + raise KconfigError("\n" + textwrap.fill( + "{}:{}: '{}' does not exist{}".format( + self._filename, self._linenr, pattern, + self._srctree_hint()), + 80)) + + for filename in filenames: + self._enter_file( + filename, + # Unless an absolute path is passed to *source, strip + # the $srctree prefix from the filename. That way it + # appears without a $srctree prefix in + # MenuNode.filename, which is nice e.g. when generating + # documentation. + filename if isabs else + os.path.relpath(filename, self.srctree)) + + prev = self._parse_block(None, parent, prev) + + self._leave_file() + + elif t0 == end_token: + # We have reached the end of the block. Terminate the final + # node and return it. + prev.next = None + return prev + + elif t0 == _T_IF: + node = MenuNode() + node.item = node.prompt = None + node.parent = parent + node.filename = self._filename + node.linenr = self._linenr + + node.dep = self._parse_expr(True) + + self._parse_block(_T_ENDIF, node, node) + node.list = node.next + + prev.next = prev = node + + elif t0 == _T_MENU: + node = MenuNode() + node.kconfig = self + node.item = MENU + node.is_menuconfig = True + node.prompt = (self._expect_str_and_eol(), self.y) + node.visibility = self.y + node.parent = parent + node.filename = self._filename + node.linenr = self._linenr + + self.menus.append(node) + + self._parse_properties(node) + self._parse_block(_T_ENDMENU, node, node) + node.list = node.next + + prev.next = prev = node + + elif t0 == _T_COMMENT: + node = MenuNode() + node.kconfig = self + node.item = COMMENT + node.is_menuconfig = False + node.prompt = (self._expect_str_and_eol(), self.y) + node.list = None + node.parent = parent + node.filename = self._filename + node.linenr = self._linenr + + self.comments.append(node) + + self._parse_properties(node) + + prev.next = prev = node + + elif t0 == _T_CHOICE: + if self._peek_token() is None: + choice = Choice() + choice.direct_dep = self.n + + self.choices.append(choice) + else: + # Named choice + name = self._expect_str_and_eol() + choice = self.named_choices.get(name) + if not choice: + choice = Choice() + choice.name = name + choice.direct_dep = self.n + + self.choices.append(choice) + self.named_choices[name] = choice + + choice.kconfig = self + + node = MenuNode() + node.kconfig = self + node.item = choice + node.is_menuconfig = True + node.prompt = node.help = None + node.parent = parent + node.filename = self._filename + node.linenr = self._linenr + + choice.nodes.append(node) + + self._parse_properties(node) + self._parse_block(_T_ENDCHOICE, node, node) + node.list = node.next + + prev.next = prev = node + + elif t0 == _T_MAINMENU: + self.top_node.prompt = (self._expect_str_and_eol(), self.y) + self.top_node.filename = self._filename + self.top_node.linenr = self._linenr + + else: + self._parse_error("unrecognized construct") + + # End of file reached. Terminate the final node and return it. + + if end_token: + raise KconfigError("Unexpected end of file " + self._filename) + + prev.next = None + return prev + + def _parse_cond(self): + # Parses an optional 'if <expr>' construct and returns the parsed + # <expr>, or self.y if the next token is not _T_IF + + expr = self._parse_expr(True) if self._check_token(_T_IF) else self.y + if self._peek_token() is not None: + self._parse_error("extra tokens at end of line") + return expr + + def _parse_properties(self, node): + # Parses and adds properties to the MenuNode 'node' (type, 'prompt', + # 'default's, etc.) Properties are later copied up to symbols and + # choices in a separate pass after parsing, in _add_props_to_sc(). + # + # An older version of this code added properties directly to symbols + # and choices instead of to their menu nodes (and handled dependency + # propagation simultaneously), but that loses information on where a + # property is added when a symbol or choice is defined in multiple + # locations. Some Kconfig configuration systems rely heavily on such + # symbols, and better docs can be generated by keeping track of where + # properties are added. + # + # node: + # The menu node we're parsing properties on + + # Dependencies from 'depends on'. Will get propagated to the properties + # below. + node.dep = self.y + + while self._next_line(): + t0 = self._next_token() + if t0 is None: + continue + + if t0 in _TYPE_TOKENS: + self._set_type(node, _TOKEN_TO_TYPE[t0]) + if self._peek_token() is not None: + self._parse_prompt(node) + + elif t0 == _T_DEPENDS: + if not self._check_token(_T_ON): + self._parse_error('expected "on" after "depends"') + + node.dep = self._make_and(node.dep, self._parse_expr(True)) + + elif t0 == _T_HELP: + self._parse_help(node) + + elif t0 == _T_SELECT: + if not isinstance(node.item, Symbol): + self._parse_error("only symbols can select") + + node.selects.append((self._expect_nonconst_sym(), + self._parse_cond())) + + elif t0 == _T_IMPLY: + if not isinstance(node.item, Symbol): + self._parse_error("only symbols can imply") + + node.implies.append((self._expect_nonconst_sym(), + self._parse_cond())) + + elif t0 == _T_DEFAULT: + node.defaults.append((self._parse_expr(False), + self._parse_cond())) + + elif t0 in (_T_DEF_BOOL, _T_DEF_TRISTATE, _T_DEF_INT, _T_DEF_HEX, + _T_DEF_STRING): + self._set_type(node, _TOKEN_TO_TYPE[t0]) + node.defaults.append((self._parse_expr(False), + self._parse_cond())) + + elif t0 == _T_PROMPT: + self._parse_prompt(node) + + elif t0 == _T_RANGE: + node.ranges.append((self._expect_sym(), + self._expect_sym(), + self._parse_cond())) + + elif t0 == _T_OPTION: + if self._check_token(_T_ENV): + if not self._check_token(_T_EQUAL): + self._parse_error('expected "=" after "env"') + + env_var = self._expect_str_and_eol() + node.item.env_var = env_var + + if env_var in os.environ: + node.defaults.append( + (self._lookup_const_sym(os.environ[env_var]), + self.y)) + else: + self._warn("{1} has 'option env=\"{0}\"', " + "but the environment variable {0} is not " + "set".format(node.item.name, env_var), + self._filename, self._linenr) + + if env_var != node.item.name: + self._warn("Kconfiglib expands environment variables " + "in strings directly, meaning you do not " + "need 'option env=...' \"bounce\" symbols. " + "For compatibility with the C tools, " + "rename {} to {} (so that the symbol name " + "matches the environment variable name)." + .format(node.item.name, env_var), + self._filename, self._linenr) + + elif self._check_token(_T_DEFCONFIG_LIST): + if not self.defconfig_list: + self.defconfig_list = node.item + else: + self._warn("'option defconfig_list' set on multiple " + "symbols ({0} and {1}). Only {0} will be " + "used.".format(self.defconfig_list.name, + node.item.name), + self._filename, self._linenr) + + elif self._check_token(_T_MODULES): + # To reduce warning spam, only warn if 'option modules' is + # set on some symbol that isn't MODULES, which should be + # safe. I haven't run into any projects that make use + # modules besides the kernel yet, and there it's likely to + # keep being called "MODULES". + if node.item is not self.modules: + self._warn("the 'modules' option is not supported. " + "Let me know if this is a problem for you, " + "as it wouldn't be that hard to implement. " + "Note that modules are supported -- " + "Kconfiglib just assumes the symbol name " + "MODULES, like older versions of the C " + "implementation did when 'option modules' " + "wasn't used.", + self._filename, self._linenr) + + elif self._check_token(_T_ALLNOCONFIG_Y): + if not isinstance(node.item, Symbol): + self._parse_error("the 'allnoconfig_y' option is only " + "valid for symbols") + + node.item.is_allnoconfig_y = True + + else: + self._parse_error("unrecognized option") + + elif t0 == _T_VISIBLE: + if not self._check_token(_T_IF): + self._parse_error('expected "if" after "visible"') + + node.visibility = \ + self._make_and(node.visibility, self._parse_expr(True)) + + elif t0 == _T_OPTIONAL: + if not isinstance(node.item, Choice): + self._parse_error('"optional" is only valid for choices') + + node.item.is_optional = True + + else: + # Reuse the tokens for the non-property line later + self._has_tokens = True + self._tokens_i = -1 + return + + def _set_type(self, node, new_type): + if node.item.orig_type not in (UNKNOWN, new_type): + self._warn("{} defined with multiple types, {} will be used" + .format(_name_and_loc(node.item), + TYPE_TO_STR[new_type])) + + node.item.orig_type = new_type + + def _parse_prompt(self, node): + # 'prompt' properties override each other within a single definition of + # a symbol, but additional prompts can be added by defining the symbol + # multiple times + if node.prompt: + self._warn(_name_and_loc(node.item) + + " defined with multiple prompts in single location") + + prompt = self._expect_str() + if prompt != prompt.strip(): + self._warn(_name_and_loc(node.item) + + " has leading or trailing whitespace in its prompt") + + # This avoid issues for e.g. reStructuredText documentation, where + # '*prompt *' is invalid + prompt = prompt.strip() + + node.prompt = (prompt, self._parse_cond()) + + def _parse_help(self, node): + # Find first non-blank (not all-space) line and get its indentation + + if node.help is not None: + self._warn(_name_and_loc(node.item) + + " defined with more than one help text -- only the " + "last one will be used") + + # Small optimization. This code is pretty hot. + readline = self._file.readline + + while 1: + line = readline() + self._linenr += 1 + if not line or not line.isspace(): + break + + if not line: + self._warn(_name_and_loc(node.item) + + " has 'help' but empty help text") + + node.help = "" + return + + indent = _indentation(line) + if indent == 0: + # If the first non-empty lines has zero indent, there is no help + # text + self._warn(_name_and_loc(node.item) + + " has 'help' but empty help text") + + node.help = "" + self._saved_line = line # "Unget" the line + return + + # The help text goes on till the first non-empty line with less indent + # than the first line + + help_lines = [] + # Small optimizations + add_help_line = help_lines.append + indentation = _indentation + + while line and (line.isspace() or indentation(line) >= indent): + # De-indent 'line' by 'indent' spaces and rstrip() it to remove any + # newlines (which gets rid of other trailing whitespace too, but + # that's fine). + # + # This prepares help text lines in a speedy way: The [indent:] + # might already remove trailing newlines for lines shorter than + # indent (e.g. empty lines). The rstrip() makes it consistent, + # meaning we can join the lines with "\n" later. + add_help_line(line.expandtabs()[indent:].rstrip()) + + line = readline() + + self._linenr += len(help_lines) + + node.help = "\n".join(help_lines).rstrip() + "\n" + self._saved_line = line # "Unget" the line + + def _parse_expr(self, transform_m): + # Parses an expression from the tokens in Kconfig._tokens using a + # simple top-down approach. See the module docstring for the expression + # format. + # + # transform_m: + # True if m should be rewritten to m && MODULES. See the + # Kconfig.eval_string() documentation. + + # Grammar: + # + # expr: and_expr ['||' expr] + # and_expr: factor ['&&' and_expr] + # factor: <symbol> ['='/'!='/'<'/... <symbol>] + # '!' factor + # '(' expr ')' + # + # It helps to think of the 'expr: and_expr' case as a single-operand OR + # (no ||), and of the 'and_expr: factor' case as a single-operand AND + # (no &&). Parsing code is always a bit tricky. + + # Mind dump: parse_factor() and two nested loops for OR and AND would + # work as well. The straightforward implementation there gives a + # (op, (op, (op, A, B), C), D) parse for A op B op C op D. Representing + # expressions as (op, [list of operands]) instead goes nicely with that + # version, but is wasteful for short expressions and complicates + # expression evaluation and other code that works on expressions (more + # complicated code likely offsets any performance gain from less + # recursion too). If we also try to optimize the list representation by + # merging lists when possible (e.g. when ANDing two AND expressions), + # we end up allocating a ton of lists instead of reusing expressions, + # which is bad. + + and_expr = self._parse_and_expr(transform_m) + + # Return 'and_expr' directly if we have a "single-operand" OR. + # Otherwise, parse the expression on the right and make an OR node. + # This turns A || B || C || D into (OR, A, (OR, B, (OR, C, D))). + return and_expr \ + if not self._check_token(_T_OR) else \ + (OR, and_expr, self._parse_expr(transform_m)) + + def _parse_and_expr(self, transform_m): + factor = self._parse_factor(transform_m) + + # Return 'factor' directly if we have a "single-operand" AND. + # Otherwise, parse the right operand and make an AND node. This turns + # A && B && C && D into (AND, A, (AND, B, (AND, C, D))). + return factor \ + if not self._check_token(_T_AND) else \ + (AND, factor, self._parse_and_expr(transform_m)) + + def _parse_factor(self, transform_m): + token = self._next_token() + + if isinstance(token, Symbol): + # Plain symbol or relation + + next_token = self._peek_token() + if next_token not in _RELATIONS: + # Plain symbol + + # For conditional expressions ('depends on <expr>', + # '... if <expr>', etc.), m is rewritten to m && MODULES. + if transform_m and token is self.m: + return (AND, self.m, self.modules) + + return token + + # Relation + # + # _T_EQUAL, _T_UNEQUAL, etc., deliberately have the same values as + # EQUAL, UNEQUAL, etc., so we can just use the token directly + return (self._next_token(), token, self._expect_sym()) + + if token == _T_NOT: + # token == _T_NOT == NOT + return (token, self._parse_factor(transform_m)) + + if token == _T_OPEN_PAREN: + expr_parse = self._parse_expr(transform_m) + if self._check_token(_T_CLOSE_PAREN): + return expr_parse + + self._parse_error("malformed expression") + + # + # Caching and invalidation + # + + def _build_dep(self): + # Populates the Symbol/Choice._dependents sets, which contain all other + # items (symbols and choices) that immediately depend on the item in + # the sense that changing the value of the item might affect the value + # of the dependent items. This is used for caching/invalidation. + # + # The calculated sets might be larger than necessary as we don't do any + # complex analysis of the expressions. + + # Only calculate _dependents for defined symbols. Constant and + # undefined symbols could theoretically be selected/implied, but it + # wouldn't change their value, so it's not a true dependency. + for sym in self._defined_syms_set: + # Symbols depend on the following: + + # The prompt conditions + for node in sym.nodes: + if node.prompt: + _make_depend_on(sym, node.prompt[1]) + + # The default values and their conditions + for value, cond in sym.defaults: + _make_depend_on(sym, value) + _make_depend_on(sym, cond) + + # The reverse and weak reverse dependencies + _make_depend_on(sym, sym.rev_dep) + _make_depend_on(sym, sym.weak_rev_dep) + + # The ranges along with their conditions + for low, high, cond in sym.ranges: + _make_depend_on(sym, low) + _make_depend_on(sym, high) + _make_depend_on(sym, cond) + + # The direct dependencies. This is usually redundant, as the direct + # dependencies get propagated to properties, but it's needed to get + # invalidation solid for 'imply', which only checks the direct + # dependencies (even if there are no properties to propagate it + # to). + _make_depend_on(sym, sym.direct_dep) + + # In addition to the above, choice symbols depend on the choice + # they're in, but that's handled automatically since the Choice is + # propagated to the conditions of the properties before + # _build_dep() runs. + + for choice in self.choices: + # Choices depend on the following: + + # The prompt conditions + for node in choice.nodes: + if node.prompt: + _make_depend_on(choice, node.prompt[1]) + + # The default symbol conditions + for _, cond in choice.defaults: + _make_depend_on(choice, cond) + + def _add_choice_deps(self): + # Choices also depend on the choice symbols themselves, because the + # y-mode selection of the choice might change if a choice symbol's + # visibility changes. + # + # We add these dependencies separately after dependency loop detection. + # The invalidation algorithm can handle the resulting + # <choice symbol> <-> <choice> dependency loops, but they make loop + # detection awkward. + + for choice in self.choices: + # The choice symbols themselves, because the y mode selection might + # change if a choice symbol's visibility changes + for sym in choice.syms: + sym._dependents.add(choice) + + def _invalidate_all(self): + # Undefined symbols never change value and don't need to be + # invalidated, so we can just iterate over defined symbols. + # Invalidating constant symbols would break things horribly. + for sym in self._defined_syms_set: + sym._invalidate() + + for choice in self.choices: + choice._invalidate() + + + # + # Post-parsing menu tree processing, including dependency propagation and + # implicit submenu creation + # + + def _finalize_tree(self, node, visible_if): + # Propagates properties and dependencies, creates implicit menus (see + # kconfig-language.txt), removes 'if' nodes, and finalizes choices. + # This pretty closely mirrors menu_finalize() from the C + # implementation, with some minor tweaks (MenuNode holds lists of + # properties instead of each property having a MenuNode pointer, for + # example). + # + # node: + # The current "parent" menu node, from which we propagate + # dependencies + # + # visible_if: + # Dependencies from 'visible if' on parent menus. These are added to + # the prompts of symbols and choices. + + if node.list: + # The menu node is a choice, menu, or if. Finalize each child in + # it. + + if node.item == MENU: + visible_if = self._make_and(visible_if, node.visibility) + + # Propagate the menu node's dependencies to each child menu node. + # + # The recursive _finalize_tree() calls assume that the current + # "level" in the tree has already had dependencies propagated. This + # makes e.g. implicit submenu creation easier, because it needs to + # look ahead. + self._propagate_deps(node, visible_if) + + # Finalize the children + cur = node.list + while cur: + self._finalize_tree(cur, visible_if) + cur = cur.next + + elif isinstance(node.item, Symbol): + # Add the node's non-node-specific properties (defaults, ranges, + # etc.) to the Symbol + self._add_props_to_sc(node) + + # See if we can create an implicit menu rooted at the Symbol and + # finalize each child menu node in that menu if so, like for the + # choice/menu/if case above + cur = node + while cur.next and _auto_menu_dep(node, cur.next): + # This also makes implicit submenu creation work recursively, + # with implicit menus inside implicit menus + self._finalize_tree(cur.next, visible_if) + cur = cur.next + cur.parent = node + + if cur is not node: + # Found symbols that should go in an implicit submenu. Tilt + # them up above us. + node.list = node.next + node.next = cur.next + cur.next = None + + + if node.list: + # We have a parent node with individually finalized child nodes. Do + # final steps to finalize this "level" in the menu tree. + _flatten(node.list) + _remove_ifs(node) + + # Empty choices (node.list None) are possible, so this needs to go + # outside + if isinstance(node.item, Choice): + # Add the node's non-node-specific properties to the choice + self._add_props_to_sc(node) + _finalize_choice(node) + + def _propagate_deps(self, node, visible_if): + # Propagates 'node's dependencies to its child menu nodes + + # If the parent node holds a Choice, we use the Choice itself as the + # parent dependency. This makes sense as the value (mode) of the choice + # limits the visibility of the contained choice symbols. The C + # implementation works the same way. + # + # Due to the similar interface, Choice works as a drop-in replacement + # for Symbol here. + basedep = node.item if isinstance(node.item, Choice) else node.dep + + cur = node.list + while cur: + cur.dep = dep = self._make_and(cur.dep, basedep) + + # Propagate dependencies to prompt + if cur.prompt: + cur.prompt = (cur.prompt[0], + self._make_and(cur.prompt[1], dep)) + + if isinstance(cur.item, (Symbol, Choice)): + sc = cur.item + + # Propagate 'visible if' dependencies to the prompt + if cur.prompt: + cur.prompt = (cur.prompt[0], + self._make_and(cur.prompt[1], visible_if)) + + # Propagate dependencies to defaults + if cur.defaults: + cur.defaults = [(default, self._make_and(cond, dep)) + for default, cond in cur.defaults] + + # Propagate dependencies to ranges + if cur.ranges: + cur.ranges = [(low, high, self._make_and(cond, dep)) + for low, high, cond in cur.ranges] + + # Propagate dependencies to selects + if cur.selects: + cur.selects = [(target, self._make_and(cond, dep)) + for target, cond in cur.selects] + + # Propagate dependencies to implies + if cur.implies: + cur.implies = [(target, self._make_and(cond, dep)) + for target, cond in cur.implies] + + + cur = cur.next + + def _add_props_to_sc(self, node): + # Copies properties from the menu node 'node' up to its contained + # symbol or choice. + # + # This can't be rolled into _propagate_deps(), because that function + # traverses the menu tree roughly breadth-first order, meaning + # properties on symbols and choices defined in multiple locations could + # end up in the wrong order. + + # Symbol or choice + sc = node.item + + # See the Symbol class docstring + sc.direct_dep = self._make_or(sc.direct_dep, node.dep) + + if node.defaults: + sc.defaults.extend(node.defaults) + + if node.ranges: + sc.ranges.extend(node.ranges) + + if node.selects: + sc.selects.extend(node.selects) + + # Modify the reverse dependencies of the selected symbol + for target, cond in node.selects: + target.rev_dep = self._make_or( + target.rev_dep, + self._make_and(sc, cond)) + + if node.implies: + sc.implies.extend(node.implies) + + # Modify the weak reverse dependencies of the implied + # symbol + for target, cond in node.implies: + target.weak_rev_dep = self._make_or( + target.weak_rev_dep, + self._make_and(sc, cond)) + + + # + # Misc. + # + + def _parse_error(self, msg): + if self._filename is None: + loc = "" + else: + loc = "{}:{}: ".format(self._filename, self._linenr) + + raise KconfigError( + "{}couldn't parse '{}': {}".format(loc, self._line.rstrip(), msg)) + + def _open(self, filename, mode): + # open() wrapper: + # + # - Enable universal newlines mode on Python 2 to ease + # interoperability between Linux and Windows. It's already the + # default on Python 3. + # + # The "U" flag would currently work for both Python 2 and 3, but it's + # deprecated on Python 3, so play it future-safe. + # + # A simpler solution would be to use io.open(), which defaults to + # universal newlines on both Python 2 and 3 (and is an alias for + # open() on Python 3), but it's appreciably slower on Python 2: + # + # Parsing x86 Kconfigs on Python 2 + # + # with open(..., "rU"): + # + # real 0m0.930s + # user 0m0.905s + # sys 0m0.025s + # + # with io.open(): + # + # real 0m1.069s + # user 0m1.040s + # sys 0m0.029s + # + # There's no appreciable performance difference between "r" and + # "rU" for parsing performance on Python 2. + # + # - For Python 3, force the encoding. Forcing the encoding on Python 2 + # turns strings into Unicode strings, which gets messy. Python 2 + # doesn't decode regular strings anyway. + return open(filename, "rU" if mode == "r" else mode) if _IS_PY2 else \ + open(filename, mode, encoding=self._encoding) + + def _check_undefined_syms(self): + # Prints warnings for all references to undefined symbols within the + # Kconfig files + + for sym in (self.syms.viewvalues() if _IS_PY2 else self.syms.values()): + # - sym.nodes empty means the symbol is undefined (has no + # definition locations) + # + # - Due to Kconfig internals, numbers show up as undefined Kconfig + # symbols, but shouldn't be flagged + # + # - The MODULES symbol always exists + if not sym.nodes and not _is_num(sym.name) and \ + sym.name != "MODULES": + + self._warn_undefined_sym(sym) + + def _warn_undefined_sym(self, sym): + # _check_undefined_syms() helper. Generates a warning that lists the + # locations where the undefined symbol 'sym' is referenced, including + # the referencing menu nodes in Kconfig format. + + referencing_nodes = [] + + def find_refs(node): + while node: + if sym in node.referenced: + referencing_nodes.append(node) + + if node.list: + find_refs(node.list) + + node = node.next + + find_refs(self.top_node) + + msg = "undefined symbol {}:".format(sym.name) + + for node in referencing_nodes: + msg += "\n\n- Referenced at {}:{}:\n\n{}" \ + .format(node.filename, node.linenr, node) + + self._warn(msg) + + def _warn(self, msg, filename=None, linenr=None): + # For printing general warnings + + if self._warnings_enabled: + msg = "warning: " + msg + if filename is not None: + msg = "{}:{}: {}".format(filename, linenr, msg) + + self.warnings.append(msg) + if self._warn_to_stderr: + sys.stderr.write(msg + "\n") + + def _warn_undef_assign(self, msg, filename=None, linenr=None): + # See the class documentation + + if self._warn_for_undef_assign: + self._warn(msg, filename, linenr) + + def _warn_undef_assign_load(self, name, val, filename, linenr): + # Special version for load_config() + + self._warn_undef_assign( + 'attempt to assign the value "{}" to the undefined symbol {}' + .format(val, name), filename, linenr) + + def _warn_redun_assign(self, msg, filename=None, linenr=None): + # See the class documentation + + if self._warn_for_redun_assign: + self._warn(msg, filename, linenr) + + def _srctree_hint(self): + # Hint printed when Kconfig files can't be found or .config files can't + # be opened + + return ". Perhaps the $srctree environment variable (set to '{}') " \ + "is set incorrectly. Note that the current value of $srctree " \ + "is saved when the Kconfig instance is created (for " \ + "consistency and to cleanly separate instances)." \ + .format(self.srctree if self.srctree else "unset or blank") + +class Symbol(object): + """ + Represents a configuration symbol: + + (menu)config FOO + ... + + The following attributes are available. They should be viewed as read-only, + and some are implemented through @property magic (but are still efficient + to access due to internal caching). + + Note: Prompts, help texts, and locations are stored in the Symbol's + MenuNode(s) rather than in the Symbol itself. Check the MenuNode class and + the Symbol.nodes attribute. This organization matches the C tools. + + name: + The name of the symbol, e.g. "FOO" for 'config FOO'. + + type: + The type of the symbol. One of BOOL, TRISTATE, STRING, INT, HEX, UNKNOWN. + UNKNOWN is for undefined symbols, (non-special) constant symbols, and + symbols defined without a type. + + When running without modules (MODULES having the value n), TRISTATE + symbols magically change type to BOOL. This also happens for symbols + within choices in "y" mode. This matches the C tools, and makes sense for + menuconfig-like functionality. + + orig_type: + The type as given in the Kconfig file, without any magic applied. Used + when printing the symbol. + + str_value: + The value of the symbol as a string. Gives the value for string/int/hex + symbols. For bool/tristate symbols, gives "n", "m", or "y". + + This is the symbol value that's used in relational expressions + (A = B, A != B, etc.) + + Gotcha: For int/hex symbols, the exact format of the value must often be + preserved (e.g., when writing a .config file), hence why you can't get it + directly as an int. Do int(int_sym.str_value) or + int(hex_sym.str_value, 16) to get the integer value. + + tri_value: + The tristate value of the symbol as an integer. One of 0, 1, 2, + representing n, m, y. Always 0 (n) for non-bool/tristate symbols. + + This is the symbol value that's used outside of relation expressions + (A, !A, A && B, A || B). + + assignable: + A tuple containing the tristate user values that can currently be + assigned to the symbol (that would be respected), ordered from lowest (0, + representing n) to highest (2, representing y). This corresponds to the + selections available in the menuconfig interface. The set of assignable + values is calculated from the symbol's visibility and selects/implies. + + Returns the empty set for non-bool/tristate symbols and for symbols with + visibility n. The other possible values are (0, 2), (0, 1, 2), (1, 2), + (1,), and (2,). A (1,) or (2,) result means the symbol is visible but + "locked" to m or y through a select, perhaps in combination with the + visibility. menuconfig represents this as -M- and -*-, respectively. + + For string/hex/int symbols, check if Symbol.visibility is non-0 (non-n) + instead to determine if the value can be changed. + + Some handy 'assignable' idioms: + + # Is 'sym' an assignable (visible) bool/tristate symbol? + if sym.assignable: + # What's the highest value it can be assigned? [-1] in Python + # gives the last element. + sym_high = sym.assignable[-1] + + # The lowest? + sym_low = sym.assignable[0] + + # Can the symbol be set to at least m? + if sym.assignable[-1] >= 1: + ... + + # Can the symbol be set to m? + if 1 in sym.assignable: + ... + + visibility: + The visibility of the symbol. One of 0, 1, 2, representing n, m, y. See + the module documentation for an overview of symbol values and visibility. + + user_value: + The user value of the symbol. None if no user value has been assigned + (via Kconfig.load_config() or Symbol.set_value()). + + Holds 0, 1, or 2 for bool/tristate symbols, and a string for the other + symbol types. + + WARNING: Do not assign directly to this. It will break things. Use + Symbol.set_value(). + + config_string: + The .config assignment string that would get written out for the symbol + by Kconfig.write_config(). Returns the empty string if no .config + assignment would get written out. In general, visible symbols, symbols + with (active) defaults, and selected symbols get written out. + + nodes: + A list of MenuNodes for this symbol. Will contain a single MenuNode for + most symbols. Undefined and constant symbols have an empty nodes list. + Symbols defined in multiple locations get one node for each location. + + choice: + Holds the parent Choice for choice symbols, and None for non-choice + symbols. Doubles as a flag for whether a symbol is a choice symbol. + + defaults: + List of (default, cond) tuples for the symbol's 'default' properties. For + example, 'default A && B if C || D' is represented as + ((AND, A, B), (OR, C, D)). If no condition was given, 'cond' is + self.kconfig.y. + + Note that 'depends on' and parent dependencies are propagated to + 'default' conditions. + + selects: + List of (symbol, cond) tuples for the symbol's 'select' properties. For + example, 'select A if B && C' is represented as (A, (AND, B, C)). If no + condition was given, 'cond' is self.kconfig.y. + + Note that 'depends on' and parent dependencies are propagated to 'select' + conditions. + + implies: + Like 'selects', for imply. + + ranges: + List of (low, high, cond) tuples for the symbol's 'range' properties. For + example, 'range 1 2 if A' is represented as (1, 2, A). If there is no + condition, 'cond' is self.config.y. + + Note that 'depends on' and parent dependencies are propagated to 'range' + conditions. + + Gotcha: 1 and 2 above will be represented as (undefined) Symbols rather + than plain integers. Undefined symbols get their name as their string + value, so this works out. The C tools work the same way. + + rev_dep: + Reverse dependency expression from other symbols selecting this symbol. + Multiple selections get ORed together. A condition on a select is ANDed + with the selecting symbol. + + For example, if A has 'select FOO' and B has 'select FOO if C', then + FOO's rev_dep will be (OR, A, (AND, B, C)). + + weak_rev_dep: + Like rev_dep, for imply. + + direct_dep: + The 'depends on' dependencies. If a symbol is defined in multiple + locations, the dependencies at each location are ORed together. + + Internally, this is used to implement 'imply', which only applies if the + implied symbol has expr_value(self.direct_dep) != 0. 'depends on' and + parent dependencies are automatically propagated to the conditions of + properties, so normally it's redundant to check the direct dependencies. + + referenced: + A set() with all symbols and choices referenced in the properties and + property conditions of the symbol. + + Also includes dependencies inherited from surrounding menus and if's. + Choices appear in the dependencies of choice symbols. + + env_var: + If the Symbol has an 'option env="FOO"' option, this contains the name + ("FOO") of the environment variable. None for symbols without no + 'option env'. + + 'option env="FOO"' acts like a 'default' property whose value is the + value of $FOO. + + Symbols with 'option env' are never written out to .config files, even if + they are visible. env_var corresponds to a flag called SYMBOL_AUTO in the + C implementation. + + is_allnoconfig_y: + True if the symbol has 'option allnoconfig_y' set on it. This has no + effect internally (except when printing symbols), but can be checked by + scripts. + + is_constant: + True if the symbol is a constant (quoted) symbol. + + kconfig: + The Kconfig instance this symbol is from. + """ + __slots__ = ( + "_cached_assignable", + "_cached_str_val", + "_cached_tri_val", + "_cached_vis", + "_checked", + "_dependents", + "_old_val", + "_was_set", + "_write_to_conf", + "_written", + "choice", + "defaults", + "direct_dep", + "env_var", + "implies", + "is_allnoconfig_y", + "is_constant", + "kconfig", + "name", + "nodes", + "orig_type", + "ranges", + "rev_dep", + "selects", + "user_value", + "weak_rev_dep", + ) + + # + # Public interface + # + + @property + def type(self): + """ + See the class documentation. + """ + if self.orig_type == TRISTATE and \ + ((self.choice and self.choice.tri_value == 2) or + not self.kconfig.modules.tri_value): + return BOOL + + return self.orig_type + + @property + def str_value(self): + """ + See the class documentation. + """ + if self._cached_str_val is not None: + return self._cached_str_val + + if self.orig_type in (BOOL, TRISTATE): + # Also calculates the visibility, so invalidation safe + self._cached_str_val = TRI_TO_STR[self.tri_value] + return self._cached_str_val + + # As a quirk of Kconfig, undefined symbols get their name as their + # string value. This is why things like "FOO = bar" work for seeing if + # FOO has the value "bar". + if self.orig_type == UNKNOWN: + self._cached_str_val = self.name + return self.name + + val = "" + # Warning: See Symbol._rec_invalidate(), and note that this is a hidden + # function call (property magic) + vis = self.visibility + + self._write_to_conf = (vis != 0) + + if self.orig_type in (INT, HEX): + # The C implementation checks the user value against the range in a + # separate code path (post-processing after loading a .config). + # Checking all values here instead makes more sense for us. It + # requires that we check for a range first. + + base = _TYPE_TO_BASE[self.orig_type] + + # Check if a range is in effect + for low_expr, high_expr, cond in self.ranges: + if expr_value(cond): + has_active_range = True + + # The zeros are from the C implementation running strtoll() + # on empty strings + low = int(low_expr.str_value, base) if \ + _is_base_n(low_expr.str_value, base) else 0 + high = int(high_expr.str_value, base) if \ + _is_base_n(high_expr.str_value, base) else 0 + + break + else: + has_active_range = False + + # Defaults are used if the symbol is invisible, lacks a user value, + # or has an out-of-range user value. + use_defaults = True + + if vis and self.user_value: + user_val = int(self.user_value, base) + if has_active_range and not low <= user_val <= high: + num2str = str if base == 10 else hex + self.kconfig._warn( + "user value {} on the {} symbol {} ignored due to " + "being outside the active range ([{}, {}]) -- falling " + "back on defaults" + .format(num2str(user_val), TYPE_TO_STR[self.orig_type], + _name_and_loc(self), + num2str(low), num2str(high))) + else: + # If the user value is well-formed and satisfies range + # contraints, it is stored in exactly the same form as + # specified in the assignment (with or without "0x", etc.) + val = self.user_value + use_defaults = False + + if use_defaults: + # No user value or invalid user value. Look at defaults. + + # Used to implement the warning below + has_default = False + + for val_sym, cond in self.defaults: + if expr_value(cond): + has_default = self._write_to_conf = True + + val = val_sym.str_value + + if _is_base_n(val, base): + val_num = int(val, base) + else: + val_num = 0 # strtoll() on empty string + + break + else: + val_num = 0 # strtoll() on empty string + + # This clamping procedure runs even if there's no default + if has_active_range: + clamp = None + if val_num < low: + clamp = low + elif val_num > high: + clamp = high + + if clamp is not None: + # The value is rewritten to a standard form if it is + # clamped + val = str(clamp) \ + if self.orig_type == INT else \ + hex(clamp) + + if has_default: + num2str = str if base == 10 else hex + self.kconfig._warn( + "default value {} on {} clamped to {} due to " + "being outside the active range ([{}, {}])" + .format(val_num, _name_and_loc(self), + num2str(clamp), num2str(low), + num2str(high))) + + elif self.orig_type == STRING: + if vis and self.user_value is not None: + # If the symbol is visible and has a user value, use that + val = self.user_value + else: + # Otherwise, look at defaults + for val_sym, cond in self.defaults: + if expr_value(cond): + val = val_sym.str_value + self._write_to_conf = True + break + + # env_var corresponds to SYMBOL_AUTO in the C implementation, and is + # also set on the defconfig_list symbol there. Test for the + # defconfig_list symbol explicitly instead here, to avoid a nonsensical + # env_var setting and the defconfig_list symbol being printed + # incorrectly. This code is pretty cold anyway. + if self.env_var is not None or self is self.kconfig.defconfig_list: + self._write_to_conf = False + + self._cached_str_val = val + return val + + @property + def tri_value(self): + """ + See the class documentation. + """ + if self._cached_tri_val is not None: + return self._cached_tri_val + + if self.orig_type not in (BOOL, TRISTATE): + if self.orig_type != UNKNOWN: + # Would take some work to give the location here + self.kconfig._warn( + "The {} symbol {} is being evaluated in a logical context " + "somewhere. It will always evaluate to n." + .format(TYPE_TO_STR[self.orig_type], _name_and_loc(self))) + + self._cached_tri_val = 0 + return 0 + + # Warning: See Symbol._rec_invalidate(), and note that this is a hidden + # function call (property magic) + vis = self.visibility + self._write_to_conf = (vis != 0) + + val = 0 + + if not self.choice: + # Non-choice symbol + + if vis and self.user_value is not None: + # If the symbol is visible and has a user value, use that + val = min(self.user_value, vis) + + else: + # Otherwise, look at defaults and weak reverse dependencies + # (implies) + + for default, cond in self.defaults: + cond_val = expr_value(cond) + if cond_val: + val = min(expr_value(default), cond_val) + if val: + self._write_to_conf = True + break + + # Weak reverse dependencies are only considered if our + # direct dependencies are met + weak_rev_dep_val = expr_value(self.weak_rev_dep) + if weak_rev_dep_val and expr_value(self.direct_dep): + val = max(weak_rev_dep_val, val) + self._write_to_conf = True + + # Reverse (select-related) dependencies take precedence + rev_dep_val = expr_value(self.rev_dep) + if rev_dep_val: + if expr_value(self.direct_dep) < rev_dep_val: + self._warn_select_unsatisfied_deps() + + val = max(rev_dep_val, val) + self._write_to_conf = True + + # m is promoted to y for (1) bool symbols and (2) symbols with a + # weak_rev_dep (from imply) of y + if val == 1 and \ + (self.type == BOOL or expr_value(self.weak_rev_dep) == 2): + val = 2 + + elif vis == 2: + # Visible choice symbol in y-mode choice. The choice mode limits + # the visibility of choice symbols, so it's sufficient to just + # check the visibility of the choice symbols themselves. + val = 2 if self.choice.selection is self else 0 + + elif vis and self.user_value: + # Visible choice symbol in m-mode choice, with set non-0 user value + val = 1 + + self._cached_tri_val = val + return val + + @property + def assignable(self): + """ + See the class documentation. + """ + if self._cached_assignable is None: + self._cached_assignable = self._assignable() + + return self._cached_assignable + + @property + def visibility(self): + """ + See the class documentation. + """ + if self._cached_vis is None: + self._cached_vis = _visibility(self) + + return self._cached_vis + + @property + def config_string(self): + """ + See the class documentation. + """ + # Note: _write_to_conf is determined when the value is calculated. This + # is a hidden function call due to property magic. + val = self.str_value + if not self._write_to_conf: + return "" + + if self.orig_type in (BOOL, TRISTATE): + return "{}{}={}\n" \ + .format(self.kconfig.config_prefix, self.name, val) \ + if val != "n" else \ + "# {}{} is not set\n" \ + .format(self.kconfig.config_prefix, self.name) + + if self.orig_type in (INT, HEX): + return "{}{}={}\n" \ + .format(self.kconfig.config_prefix, self.name, val) + + if self.orig_type == STRING: + return '{}{}="{}"\n' \ + .format(self.kconfig.config_prefix, self.name, escape(val)) + + _internal_error("Internal error while creating .config: unknown " + 'type "{}".'.format(self.orig_type)) + + def set_value(self, value): + """ + Sets the user value of the symbol. + + Equal in effect to assigning the value to the symbol within a .config + file. For bool and tristate symbols, use the 'assignable' attribute to + check which values can currently be assigned. Setting values outside + 'assignable' will cause Symbol.user_value to differ from + Symbol.str/tri_value (be truncated down or up). + + Setting a choice symbol to 2 (y) sets Choice.user_selection to the + choice symbol in addition to setting Symbol.user_value. + Choice.user_selection is considered when the choice is in y mode (the + "normal" mode). + + Other symbols that depend (possibly indirectly) on this symbol are + automatically recalculated to reflect the assigned value. + + value: + The user value to give to the symbol. For bool and tristate symbols, + n/m/y can be specified either as 0/1/2 (the usual format for tristate + values in Kconfiglib) or as one of the strings "n"/"m"/"y". For other + symbol types, pass a string. + + Values that are invalid for the type (such as "foo" or 1 (m) for a + BOOL or "0x123" for an INT) are ignored and won't be stored in + Symbol.user_value. Kconfiglib will print a warning by default for + invalid assignments, and set_value() will return False. + + Returns True if the value is valid for the type of the symbol, and + False otherwise. This only looks at the form of the value. For BOOL and + TRISTATE symbols, check the Symbol.assignable attribute to see what + values are currently in range and would actually be reflected in the + value of the symbol. For other symbol types, check whether the + visibility is non-n. + """ + # If the new user value matches the old, nothing changes, and we can + # save some work. + # + # This optimization is skipped for choice symbols: Setting a choice + # symbol's user value to y might change the state of the choice, so it + # wouldn't be safe (symbol user values always match the values set in a + # .config file or via set_value(), and are never implicitly updated). + if value == self.user_value and not self.choice: + self._was_set = True + return True + + # Check if the value is valid for our type + if not (self.orig_type == BOOL and value in (0, 2, "n", "y") or + self.orig_type == TRISTATE and value in (0, 1, 2, "n", "m", "y") or + (isinstance(value, str) and + (self.orig_type == STRING or + self.orig_type == INT and _is_base_n(value, 10) or + self.orig_type == HEX and _is_base_n(value, 16) + and int(value, 16) >= 0))): + + # Display tristate values as n, m, y in the warning + self.kconfig._warn( + "the value {} is invalid for {}, which has type {} -- " + "assignment ignored" + .format(TRI_TO_STR[value] if value in (0, 1, 2) else + "'{}'".format(value), + _name_and_loc(self), + TYPE_TO_STR[self.orig_type])) + + return False + + if self.env_var is not None: + self.kconfig._warn("ignored attempt to assign user value to " + "{}, which is set from the environment" + .format(_name_and_loc(self))) + return False + + if self.orig_type in (BOOL, TRISTATE) and value in ("n", "m", "y"): + value = STR_TO_TRI[value] + + self.user_value = value + self._was_set = True + + if self.choice and value == 2: + # Setting a choice symbol to y makes it the user selection of the + # choice. Like for symbol user values, the user selection is not + # guaranteed to match the actual selection of the choice, as + # dependencies come into play. + self.choice.user_selection = self + self.choice._was_set = True + self.choice._rec_invalidate() + else: + self._rec_invalidate_if_has_prompt() + + return True + + def unset_value(self): + """ + Resets the user value of the symbol, as if the symbol had never gotten + a user value via Kconfig.load_config() or Symbol.set_value(). + """ + if self.user_value is not None: + self.user_value = None + self._rec_invalidate_if_has_prompt() + + @property + def referenced(self): + """ + See the class documentation. + """ + res = set() + for node in self.nodes: + res |= node.referenced + + return res + + def __repr__(self): + """ + Returns a string with information about the symbol (including its name, + value, visibility, and location(s)) when it is evaluated on e.g. the + interactive Python prompt. + """ + fields = [] + + fields.append("symbol " + self.name) + fields.append(TYPE_TO_STR[self.type]) + + for node in self.nodes: + if node.prompt: + fields.append('"{}"'.format(node.prompt[0])) + + # Only add quotes for non-bool/tristate symbols + fields.append("value " + + (self.str_value + if self.orig_type in (BOOL, TRISTATE) else + '"{}"'.format(self.str_value))) + + if not self.is_constant: + # These aren't helpful to show for constant symbols + + if self.user_value is not None: + # Only add quotes for non-bool/tristate symbols + fields.append("user value " + + (TRI_TO_STR[self.user_value] + if self.orig_type in (BOOL, TRISTATE) else + '"{}"'.format(self.user_value))) + + fields.append("visibility " + TRI_TO_STR[self.visibility]) + + if self.choice: + fields.append("choice symbol") + + if self.is_allnoconfig_y: + fields.append("allnoconfig_y") + + if self is self.kconfig.defconfig_list: + fields.append("is the defconfig_list symbol") + + if self.env_var is not None: + fields.append("from environment variable " + self.env_var) + + if self is self.kconfig.modules: + fields.append("is the modules symbol") + + fields.append("direct deps " + + TRI_TO_STR[expr_value(self.direct_dep)]) + + if self.nodes: + for node in self.nodes: + fields.append("{}:{}".format(node.filename, node.linenr)) + else: + if self.is_constant: + fields.append("constant") + else: + fields.append("undefined") + + return "<{}>".format(", ".join(fields)) + + def __str__(self): + """ + Returns a string representation of the symbol when it is printed, + matching the Kconfig format, with parent dependencies propagated. + + The string is constructed by joining the strings returned by + MenuNode.__str__() for each of the symbol's menu nodes, so symbols + defined in multiple locations will return a string with all + definitions. + + An empty string is returned for undefined and constant symbols. + """ + return "\n".join(str(node) for node in self.nodes) + + # + # Private methods + # + + def __init__(self): + """ + Symbol constructor -- not intended to be called directly by Kconfiglib + clients. + """ + # These attributes are always set on the instance from outside and + # don't need defaults: + # _written + # kconfig + # direct_dep + # is_constant + # name + # rev_dep + # weak_rev_dep + + self.orig_type = UNKNOWN + self.defaults = [] + self.selects = [] + self.implies = [] + self.ranges = [] + + self.nodes = [] + + self.user_value = \ + self.choice = \ + self.env_var = \ + self._cached_str_val = self._cached_tri_val = self._cached_vis = \ + self._cached_assignable = None + + # _write_to_conf is calculated along with the value. If True, the + # Symbol gets a .config entry. + + self.is_allnoconfig_y = \ + self._was_set = \ + self._write_to_conf = False + + # See Kconfig._build_dep() + self._dependents = set() + + # Used during dependency loop detection + self._checked = 0 + + def _assignable(self): + # Worker function for the 'assignable' attribute + + if self.orig_type not in (BOOL, TRISTATE): + return () + + # Warning: See Symbol._rec_invalidate(), and note that this is a hidden + # function call (property magic) + vis = self.visibility + + if not vis: + return () + + rev_dep_val = expr_value(self.rev_dep) + + if vis == 2: + if self.choice: + return (2,) + + if not rev_dep_val: + if self.type == BOOL or expr_value(self.weak_rev_dep) == 2: + return (0, 2) + return (0, 1, 2) + + if rev_dep_val == 2: + return (2,) + + # rev_dep_val == 1 + + if self.type == BOOL or expr_value(self.weak_rev_dep) == 2: + return (2,) + return (1, 2) + + # vis == 1 + + # Must be a tristate here, because bool m visibility gets promoted to y + + if not rev_dep_val: + return (0, 1) if expr_value(self.weak_rev_dep) != 2 else (0, 2) + + if rev_dep_val == 2: + return (2,) + + # vis == rev_dep_val == 1 + + return (1,) + + def _invalidate(self): + # Marks the symbol as needing to be recalculated + + self._cached_str_val = self._cached_tri_val = self._cached_vis = \ + self._cached_assignable = None + + def _rec_invalidate(self): + # Invalidates the symbol and all items that (possibly) depend on it + + if self is self.kconfig.modules: + # Invalidating MODULES has wide-ranging effects + self.kconfig._invalidate_all() + else: + self._invalidate() + + for item in self._dependents: + # _cached_vis doubles as a flag that tells us whether 'item' + # has cached values, because it's calculated as a side effect + # of calculating all other (non-constant) cached values. + # + # If item._cached_vis is None, it means there can't be cached + # values on other items that depend on 'item', because if there + # were, some value on 'item' would have been calculated and + # item._cached_vis set as a side effect. It's therefore safe to + # stop the invalidation at symbols with _cached_vis None. + # + # This approach massively speeds up scripts that set a lot of + # values, vs simply invalidating all possibly dependent symbols + # (even when you already have a list of all the dependent + # symbols, because some symbols get huge dependency trees). + # + # This gracefully handles dependency loops too, which is nice + # for choices, where the choice depends on the choice symbols + # and vice versa. + if item._cached_vis is not None: + item._rec_invalidate() + + def _rec_invalidate_if_has_prompt(self): + # Invalidates the symbol and its dependent symbols, but only if the + # symbol has a prompt. User values never have an effect on promptless + # symbols, so we skip invalidation for them as an optimization. + # + # This also prevents constant (quoted) symbols from being invalidated + # if set_value() is called on them, which would cause them to lose + # their value and break things. + # + # Prints a warning if the symbol has no prompt. In some contexts (e.g. + # when loading a .config files) assignments to promptless symbols are + # normal and expected, so the warning can be disabled. + + for node in self.nodes: + if node.prompt: + self._rec_invalidate() + return + + if self.kconfig._warn_for_no_prompt: + self.kconfig._warn(_name_and_loc(self) + " has no prompt, meaning " + "user values have no effect on it") + + def _str_default(self): + # write_min_config() helper function. Returns the value the symbol + # would get from defaults if it didn't have a user value. Uses exactly + # the same algorithm as the C implementation (though a bit cleaned up), + # for compatibility. + + if self.orig_type in (BOOL, TRISTATE): + val = 0 + + # Defaults, selects, and implies do not affect choice symbols + if not self.choice: + for default, cond in self.defaults: + cond_val = expr_value(cond) + if cond_val: + val = min(expr_value(default), cond_val) + break + + val = max(expr_value(self.rev_dep), + expr_value(self.weak_rev_dep), + val) + + # Transpose mod to yes if type is bool (possibly due to modules + # being disabled) + if val == 1 and self.type == BOOL: + val = 2 + + return TRI_TO_STR[val] + + if self.orig_type in (STRING, INT, HEX): + for default, cond in self.defaults: + if expr_value(cond): + return default.str_value + + return "" + + def _warn_select_unsatisfied_deps(self): + # Helper for printing an informative warning when a symbol with + # unsatisfied direct dependencies (dependencies from 'depends on', ifs, + # and menus) is selected by some other symbol. Also warn if a symbol + # whose direct dependencies evaluate to m is selected to y. + + dir_dep_val = expr_value(self.direct_dep) + + msg = "{} has direct dependencies {} with value {}, but is " \ + "currently being {}-selected by the following symbols:" \ + .format(_name_and_loc(self), expr_str(self.direct_dep), + TRI_TO_STR[dir_dep_val], + TRI_TO_STR[expr_value(self.rev_dep)]) + + # The reverse dependencies from each select are ORed together + for select in split_expr(self.rev_dep, OR): + select_val = expr_value(select) + if select_val <= dir_dep_val: + # Only include selects that exceed the direct dependencies + continue + + # - 'select A if B' turns into A && B + # - 'select A' just turns into A + # + # In both cases, we can split on AND and pick the first operand + selecting_sym = split_expr(select, AND)[0] + + msg += "\n - {}, with value {}, direct dependencies {} " \ + "(value: {})" \ + .format(_name_and_loc(selecting_sym), + selecting_sym.str_value, + expr_str(selecting_sym.direct_dep), + TRI_TO_STR[expr_value(selecting_sym.direct_dep)]) + + if isinstance(select, tuple): + msg += ", and select condition {} (value: {})" \ + .format(expr_str(select[2]), + TRI_TO_STR[expr_value(select[2])]) + + self.kconfig._warn(msg) + +class Choice(object): + """ + Represents a choice statement: + + choice + ... + endchoice + + The following attributes are available on Choice instances. They should be + treated as read-only, and some are implemented through @property magic (but + are still efficient to access due to internal caching). + + Note: Prompts, help texts, and locations are stored in the Choice's + MenuNode(s) rather than in the Choice itself. Check the MenuNode class and + the Choice.nodes attribute. This organization matches the C tools. + + name: + The name of the choice, e.g. "FOO" for 'choice FOO', or None if the + Choice has no name. I can't remember ever seeing named choices in + practice, but the C tools support them too. + + type: + The type of the choice. One of BOOL, TRISTATE, UNKNOWN. UNKNOWN is for + choices defined without a type where none of the contained symbols have a + type either (otherwise the choice inherits the type of the first symbol + defined with a type). + + When running without modules (CONFIG_MODULES=n), TRISTATE choices + magically change type to BOOL. This matches the C tools, and makes sense + for menuconfig-like functionality. + + orig_type: + The type as given in the Kconfig file, without any magic applied. Used + when printing the choice. + + tri_value: + The tristate value (mode) of the choice. A choice can be in one of three + modes: + + 0 (n) - The choice is disabled and no symbols can be selected. For + visible choices, this mode is only possible for choices with + the 'optional' flag set (see kconfig-language.txt). + + 1 (m) - Any number of choice symbols can be set to m, the rest will + be n. + + 2 (y) - One symbol will be y, the rest n. + + Only tristate choices can be in m mode. The visibility of the choice is + an upper bound on the mode, and the mode in turn is an upper bound on the + visibility of the choice symbols. + + To change the mode, use Choice.set_value(). + + Implementation note: + The C tools internally represent choices as a type of symbol, with + special-casing in many code paths. This is why there is a lot of + similarity to Symbol. The value (mode) of a choice is really just a + normal symbol value, and an implicit reverse dependency forces its + lower bound to m for visible non-optional choices (the reverse + dependency is 'm && <visibility>'). + + Symbols within choices get the choice propagated as a dependency to + their properties. This turns the mode of the choice into an upper bound + on e.g. the visibility of choice symbols, and explains the gotcha + related to printing choice symbols mentioned in the module docstring. + + Kconfiglib uses a separate Choice class only because it makes the code + and interface less confusing (especially in a user-facing interface). + Corresponding attributes have the same name in the Symbol and Choice + classes, for consistency and compatibility. + + assignable: + See the symbol class documentation. Gives the assignable values (modes). + + visibility: + See the Symbol class documentation. Acts on the value (mode). + + selection: + The Symbol instance of the currently selected symbol. None if the Choice + is not in y mode or has no selected symbol (due to unsatisfied + dependencies on choice symbols). + + WARNING: Do not assign directly to this. It will break things. Call + sym.set_value(2) on the choice symbol you want to select instead. + + user_value: + The value (mode) selected by the user through Choice.set_value(). Either + 0, 1, or 2, or None if the user hasn't selected a mode. See + Symbol.user_value. + + WARNING: Do not assign directly to this. It will break things. Use + Choice.set_value() instead. + + user_selection: + The symbol selected by the user (by setting it to y). Ignored if the + choice is not in y mode, but still remembered so that the choice "snaps + back" to the user selection if the mode is changed back to y. This might + differ from 'selection' due to unsatisfied dependencies. + + WARNING: Do not assign directly to this. It will break things. Call + sym.set_value(2) on the choice symbol to be selected instead. + + syms: + List of symbols contained in the choice. + + Gotcha: If a symbol depends on the previous symbol within a choice so + that an implicit menu is created, it won't be a choice symbol, and won't + be included in 'syms'. There are real-world examples of this, and it was + a PITA to support in older versions of Kconfiglib that didn't implement + the menu structure. + + nodes: + A list of MenuNodes for this choice. In practice, the list will probably + always contain a single MenuNode, but it is possible to give a choice a + name and define it in multiple locations (I've never even seen a named + choice though). + + defaults: + List of (symbol, cond) tuples for the choice's 'defaults' properties. For + example, 'default A if B && C' is represented as (A, (AND, B, C)). If + there is no condition, 'cond' is self.config.y. + + Note that 'depends on' and parent dependencies are propagated to + 'default' conditions. + + direct_dep: + See Symbol.direct_dep. + + referenced: + A set() with all symbols referenced in the properties and property + conditions of the choice. + + Also includes dependencies inherited from surrounding menus and if's. + + is_optional: + True if the choice has the 'optional' flag set on it and can be in + n mode. + + kconfig: + The Kconfig instance this choice is from. + """ + __slots__ = ( + "_cached_assignable", + "_cached_selection", + "_cached_vis", + "_checked", + "_dependents", + "_was_set", + "defaults", + "direct_dep", + "is_constant", + "is_optional", + "kconfig", + "name", + "nodes", + "orig_type", + "syms", + "user_selection", + "user_value", + ) + + # + # Public interface + # + + @property + def type(self): + """ + Returns the type of the choice. See Symbol.type. + """ + if self.orig_type == TRISTATE and not self.kconfig.modules.tri_value: + return BOOL + + return self.orig_type + + @property + def str_value(self): + """ + See the class documentation. + """ + return TRI_TO_STR[self.tri_value] + + @property + def tri_value(self): + """ + See the class documentation. + """ + # This emulates a reverse dependency of 'm && visibility' for + # non-optional choices, which is how the C implementation does it + + val = 0 if self.is_optional else 1 + + if self.user_value is not None: + val = max(val, self.user_value) + + # Warning: See Symbol._rec_invalidate(), and note that this is a hidden + # function call (property magic) + val = min(val, self.visibility) + + # Promote m to y for boolean choices + return 2 if val == 1 and self.type == BOOL else val + + @property + def assignable(self): + """ + See the class documentation. + """ + if self._cached_assignable is None: + self._cached_assignable = self._assignable() + + return self._cached_assignable + + @property + def visibility(self): + """ + See the class documentation. + """ + if self._cached_vis is None: + self._cached_vis = _visibility(self) + + return self._cached_vis + + @property + def selection(self): + """ + See the class documentation. + """ + if self._cached_selection is _NO_CACHED_SELECTION: + self._cached_selection = self._selection() + + return self._cached_selection + + def set_value(self, value): + """ + Sets the user value (mode) of the choice. Like for Symbol.set_value(), + the visibility might truncate the value. Choices without the 'optional' + attribute (is_optional) can never be in n mode, but 0/"n" is still + accepted since it's not a malformed value (though it will have no + effect). + + Returns True if the value is valid for the type of the choice, and + False otherwise. This only looks at the form of the value. Check the + Choice.assignable attribute to see what values are currently in range + and would actually be reflected in the mode of the choice. + """ + if value == self.user_value: + # We know the value must be valid if it was successfully set + # previously + self._was_set = True + return True + + if not ((self.orig_type == BOOL and value in (0, 2, "n", "y") ) or + (self.orig_type == TRISTATE and value in (0, 1, 2, "n", "m", "y"))): + + # Display tristate values as n, m, y in the warning + self.kconfig._warn( + "the value {} is invalid for {}, which has type {} -- " + "assignment ignored" + .format(TRI_TO_STR[value] if value in (0, 1, 2) else + "'{}'".format(value), + _name_and_loc(self), + TYPE_TO_STR[self.orig_type])) + + return False + + if value in ("n", "m", "y"): + value = STR_TO_TRI[value] + + self.user_value = value + self._was_set = True + self._rec_invalidate() + + return True + + def unset_value(self): + """ + Resets the user value (mode) and user selection of the Choice, as if + the user had never touched the mode or any of the choice symbols. + """ + if self.user_value is not None or self.user_selection: + self.user_value = self.user_selection = None + self._rec_invalidate() + + @property + def referenced(self): + """ + See the class documentation. + """ + res = set() + for node in self.nodes: + res |= node.referenced + + return res + + def __repr__(self): + """ + Returns a string with information about the choice when it is evaluated + on e.g. the interactive Python prompt. + """ + fields = [] + + fields.append("choice" if self.name is None else \ + "choice " + self.name) + fields.append(TYPE_TO_STR[self.type]) + + for node in self.nodes: + if node.prompt: + fields.append('"{}"'.format(node.prompt[0])) + + fields.append("mode " + self.str_value) + + if self.user_value is not None: + fields.append('user mode {}'.format(TRI_TO_STR[self.user_value])) + + if self.selection: + fields.append("{} selected".format(self.selection.name)) + + if self.user_selection: + user_sel_str = "{} selected by user" \ + .format(self.user_selection.name) + + if self.selection is not self.user_selection: + user_sel_str += " (overridden)" + + fields.append(user_sel_str) + + fields.append("visibility " + TRI_TO_STR[self.visibility]) + + if self.is_optional: + fields.append("optional") + + for node in self.nodes: + fields.append("{}:{}".format(node.filename, node.linenr)) + + return "<{}>".format(", ".join(fields)) + + def __str__(self): + """ + Returns a string representation of the choice when it is printed, + matching the Kconfig format (though without the contained choice + symbols). + + See Symbol.__str__() as well. + """ + return "\n".join(str(node) for node in self.nodes) + + # + # Private methods + # + + def __init__(self): + """ + Choice constructor -- not intended to be called directly by Kconfiglib + clients. + """ + # These attributes are always set on the instance from outside and + # don't need defaults: + # direct_dep + # kconfig + + self.orig_type = UNKNOWN + self.syms = [] + self.defaults = [] + + self.nodes = [] + + self.name = \ + self.user_value = self.user_selection = \ + self._cached_vis = self._cached_assignable = None + + self._cached_selection = _NO_CACHED_SELECTION + + # is_constant is checked by _make_depend_on(). Just set it to avoid + # having to special-case choices. + self.is_constant = self.is_optional = False + + # See Kconfig._build_dep() + self._dependents = set() + + # Used during dependency loop detection + self._checked = 0 + + def _assignable(self): + # Worker function for the 'assignable' attribute + + # Warning: See Symbol._rec_invalidate(), and note that this is a hidden + # function call (property magic) + vis = self.visibility + + if not vis: + return () + + if vis == 2: + if not self.is_optional: + return (2,) if self.type == BOOL else (1, 2) + return (0, 2) if self.type == BOOL else (0, 1, 2) + + # vis == 1 + + return (0, 1) if self.is_optional else (1,) + + def _selection(self): + # Worker function for the 'selection' attribute + + # Warning: See Symbol._rec_invalidate(), and note that this is a hidden + # function call (property magic) + if self.tri_value != 2: + # Not in y mode, so no selection + return None + + # Use the user selection if it's visible + if self.user_selection and self.user_selection.visibility: + return self.user_selection + + # Otherwise, check if we have a default + return self._get_selection_from_defaults() + + def _get_selection_from_defaults(self): + # Check if we have a default + for sym, cond in self.defaults: + # The default symbol must be visible too + if expr_value(cond) and sym.visibility: + return sym + + # Otherwise, pick the first visible symbol, if any + for sym in self.syms: + if sym.visibility: + return sym + + # Couldn't find a selection + return None + + def _invalidate(self): + self._cached_vis = self._cached_assignable = None + self._cached_selection = _NO_CACHED_SELECTION + + def _rec_invalidate(self): + # See Symbol._rec_invalidate() + + self._invalidate() + + for item in self._dependents: + if item._cached_vis is not None: + item._rec_invalidate() + +class MenuNode(object): + """ + Represents a menu node in the configuration. This corresponds to an entry + in e.g. the 'make menuconfig' interface, though non-visible choices, menus, + and comments also get menu nodes. If a symbol or choice is defined in + multiple locations, it gets one menu node for each location. + + The top-level menu node, corresponding to the implicit top-level menu, is + available in Kconfig.top_node. + + The menu nodes for a Symbol or Choice can be found in the + Symbol/Choice.nodes attribute. Menus and comments are represented as plain + menu nodes, with their text stored in the prompt attribute (prompt[0]). + This mirrors the C implementation. + + The following attributes are available on MenuNode instances. They should + be viewed as read-only. + + item: + Either a Symbol, a Choice, or one of the constants MENU and COMMENT. + Menus and comments are represented as plain menu nodes. Ifs are collapsed + (matching the C implementation) and do not appear in the final menu tree. + + next: + The following menu node. None if there is no following node. + + list: + The first child menu node. None if there are no children. + + Choices and menus naturally have children, but Symbols can also have + children because of menus created automatically from dependencies (see + kconfig-language.txt). + + parent: + The parent menu node. None if there is no parent. + + prompt: + A (string, cond) tuple with the prompt for the menu node and its + conditional expression (which is self.kconfig.y if there is no + condition). None if there is no prompt. + + For symbols and choices, the prompt is stored in the MenuNode rather than + the Symbol or Choice instance. For menus and comments, the prompt holds + the text. + + defaults: + The 'default' properties for this particular menu node. See + symbol.defaults. + + When evaluating defaults, you should use Symbol/Choice.defaults instead, + as it include properties from all menu nodes (a symbol/choice can have + multiple definition locations/menu nodes). MenuNode.defaults is meant for + documentation generation. + + selects: + Like MenuNode.defaults, for selects. + + implies: + Like MenuNode.defaults, for implies. + + ranges: + Like MenuNode.defaults, for ranges. + + help: + The help text for the menu node for Symbols and Choices. None if there is + no help text. Always stored in the node rather than the Symbol or Choice. + It is possible to have a separate help text at each location if a symbol + is defined in multiple locations. + + dep: + The 'depends on' dependencies for the menu node, or self.kconfig.y if + there are no dependencies. Parent dependencies are propagated to this + attribute, and this attribute is then in turn propagated to the + properties of symbols and choices. + + If a symbol or choice is defined in multiple locations, only the + properties defined at a particular location get the corresponding + MenuNode.dep dependencies propagated to them. + + visibility: + The 'visible if' dependencies for the menu node (which must represent a + menu), or self.kconfig.y if there are no 'visible if' dependencies. + 'visible if' dependencies are recursively propagated to the prompts of + symbols and choices within the menu. + + referenced: + A set() with all symbols and choices referenced in the properties and + property conditions of the menu node. + + Also includes dependencies inherited from surrounding menus and if's. + Choices appear in the dependencies of choice symbols. + + is_menuconfig: + Set to True if the children of the menu node should be displayed in a + separate menu. This is the case for the following items: + + - Menus (node.item == MENU) + + - Choices + + - Symbols defined with the 'menuconfig' keyword. The children come from + implicitly created submenus, and should be displayed in a separate + menu rather than being indented. + + 'is_menuconfig' is just a hint on how to display the menu node. It's + ignored internally by Kconfiglib, except when printing symbols. + + filename/linenr: + The location where the menu node appears. + + kconfig: + The Kconfig instance the menu node is from. + """ + __slots__ = ( + "dep", + "filename", + "help", + "is_menuconfig", + "item", + "kconfig", + "linenr", + "list", + "next", + "parent", + "prompt", + "visibility", + + # Properties + "defaults", + "selects", + "implies", + "ranges" + ) + + def __init__(self): + # Properties defined on this particular menu node. A local 'depends on' + # only applies to these, in case a symbol is defined in multiple + # locations. + self.defaults = [] + self.selects = [] + self.implies = [] + self.ranges = [] + + @property + def referenced(self): + """ + See the class documentation. + """ + # self.dep is included to catch dependencies from a lone 'depends on' + # when there are no properties to propagate it to + res = expr_items(self.dep) + + if self.prompt: + res |= expr_items(self.prompt[1]) + + if self.item == MENU: + res |= expr_items(self.visibility) + + for value, cond in self.defaults: + res |= expr_items(value) + res |= expr_items(cond) + + for value, cond in self.selects: + res.add(value) + res |= expr_items(cond) + + for value, cond in self.implies: + res.add(value) + res |= expr_items(cond) + + for low, high, cond in self.ranges: + res.add(low) + res.add(high) + res |= expr_items(cond) + + return res + + def __repr__(self): + """ + Returns a string with information about the menu node when it is + evaluated on e.g. the interactive Python prompt. + """ + fields = [] + + if isinstance(self.item, Symbol): + fields.append("menu node for symbol " + self.item.name) + + elif isinstance(self.item, Choice): + s = "menu node for choice" + if self.item.name is not None: + s += " " + self.item.name + fields.append(s) + + elif self.item == MENU: + fields.append("menu node for menu") + + elif self.item == COMMENT: + fields.append("menu node for comment") + + elif self.item is None: + fields.append("menu node for if (should not appear in the final " + " tree)") + + else: + _internal_error("unable to determine type in MenuNode.__repr__()") + + if self.prompt: + fields.append('prompt "{}" (visibility {})' + .format(self.prompt[0], + TRI_TO_STR[expr_value(self.prompt[1])])) + + if isinstance(self.item, Symbol) and self.is_menuconfig: + fields.append("is menuconfig") + + fields.append("deps " + TRI_TO_STR[expr_value(self.dep)]) + + if self.item == MENU: + fields.append("'visible if' deps " + \ + TRI_TO_STR[expr_value(self.visibility)]) + + if isinstance(self.item, (Symbol, Choice)) and self.help is not None: + fields.append("has help") + + if self.list: + fields.append("has child") + + if self.next: + fields.append("has next") + + fields.append("{}:{}".format(self.filename, self.linenr)) + + return "<{}>".format(", ".join(fields)) + + def __str__(self): + """ + Returns a string representation of the menu node, matching the Kconfig + format. + + The output could (almost) be fed back into a Kconfig parser to redefine + the object associated with the menu node. See the module documentation + for a gotcha related to choice symbols. + + For symbols and choices with multiple menu nodes (multiple definition + locations), properties that aren't associated with a particular menu + node are shown on all menu nodes ('option env=...', 'optional' for + choices, etc.). + """ + + return self._menu_comment_node_str() \ + if self.item in (MENU, COMMENT) else \ + self._sym_choice_node_str() + + def _menu_comment_node_str(self): + s = '{} "{}"\n'.format("menu" if self.item == MENU else "comment", + self.prompt[0]) + + if self.dep is not self.kconfig.y: + s += "\tdepends on {}\n".format(expr_str(self.dep)) + + if self.item == MENU and self.visibility is not self.kconfig.y: + s += "\tvisible if {}\n".format(expr_str(self.visibility)) + + return s + + def _sym_choice_node_str(self): + lines = [] + + def indent_add(s): + lines.append("\t" + s) + + def indent_add_cond(s, cond): + if cond is not self.kconfig.y: + s += " if " + expr_str(cond) + indent_add(s) + + if isinstance(self.item, (Symbol, Choice)): + sc = self.item + + if isinstance(sc, Symbol): + lines.append( + ("menuconfig " if self.is_menuconfig else "config ") + + sc.name) + else: + lines.append( + "choice" if sc.name is None else "choice " + sc.name) + + if sc.orig_type != UNKNOWN: + indent_add(TYPE_TO_STR[sc.orig_type]) + + if self.prompt: + indent_add_cond( + 'prompt "{}"'.format(escape(self.prompt[0])), + self.prompt[1]) + + if isinstance(sc, Symbol): + if sc.is_allnoconfig_y: + indent_add("option allnoconfig_y") + + if sc is sc.kconfig.defconfig_list: + indent_add("option defconfig_list") + + if sc.env_var is not None: + indent_add('option env="{}"'.format(sc.env_var)) + + if sc is sc.kconfig.modules: + indent_add("option modules") + + for low, high, cond in self.ranges: + indent_add_cond( + "range {} {}".format(expr_str(low), expr_str(high)), + cond) + + for default, cond in self.defaults: + indent_add_cond("default " + expr_str(default), cond) + + if isinstance(sc, Choice) and sc.is_optional: + indent_add("optional") + + if isinstance(sc, Symbol): + for select, cond in self.selects: + indent_add_cond("select " + expr_str(select), cond) + + for imply, cond in self.implies: + indent_add_cond("imply " + expr_str(imply), cond) + + if self.dep is not sc.kconfig.y: + indent_add("depends on " + expr_str(self.dep)) + + if self.help is not None: + indent_add("help") + for line in self.help.splitlines(): + indent_add(" " + line) + + return "\n".join(lines) + "\n" + +class Variable(object): + """ + Represents a preprocessor variable/function. + + The following attributes are available: + + name: + The name of the variable. + + value: + The unexpanded value of the variable. + + expanded_value: + The expanded value of the variable. For simple variables (those defined + with :=), this will equal 'value'. Accessing this property will raise a + KconfigError if any variable in the expansion expands to itself. + + is_recursive: + True if the variable is recursive (defined with =). + """ + __slots__ = ( + "_n_expansions", + "is_recursive", + "kconfig", + "name", + "value", + ) + + @property + def expanded_value(self): + """ + See the class documentation. + """ + return self.kconfig._expand_whole(self.value, ()) + +class KconfigError(Exception): + """ + Exception raised for Kconfig-related errors. + """ + +# Backwards compatibility +KconfigSyntaxError = KconfigError + +class InternalError(Exception): + """ + Exception raised for internal errors. + """ + +# +# Public functions +# + +def expr_value(expr): + """ + Evaluates the expression 'expr' to a tristate value. Returns 0 (n), 1 (m), + or 2 (y). + + 'expr' must be an already-parsed expression from a Symbol, Choice, or + MenuNode property. To evaluate an expression represented as a string, use + Kconfig.eval_string(). + + Passing subexpressions of expressions to this function works as expected. + """ + if not isinstance(expr, tuple): + return expr.tri_value + + if expr[0] == AND: + v1 = expr_value(expr[1]) + # Short-circuit the n case as an optimization (~5% faster + # allnoconfig.py and allyesconfig.py, as of writing) + return 0 if not v1 else min(v1, expr_value(expr[2])) + + if expr[0] == OR: + v1 = expr_value(expr[1]) + # Short-circuit the y case as an optimization + return 2 if v1 == 2 else max(v1, expr_value(expr[2])) + + if expr[0] == NOT: + return 2 - expr_value(expr[1]) + + if expr[0] in _RELATIONS: + # Implements <, <=, >, >= comparisons as well. These were added to + # kconfig in 31847b67 (kconfig: allow use of relations other than + # (in)equality). + + oper, op1, op2 = expr + + # If both operands are strings... + if op1.orig_type == STRING and op2.orig_type == STRING: + # ...then compare them lexicographically + comp = _strcmp(op1.str_value, op2.str_value) + else: + # Otherwise, try to compare them as numbers + try: + comp = _sym_to_num(op1) - _sym_to_num(op2) + except ValueError: + # Fall back on a lexicographic comparison if the operands don't + # parse as numbers + comp = _strcmp(op1.str_value, op2.str_value) + + if oper == EQUAL: res = comp == 0 + elif oper == UNEQUAL: res = comp != 0 + elif oper == LESS: res = comp < 0 + elif oper == LESS_EQUAL: res = comp <= 0 + elif oper == GREATER: res = comp > 0 + elif oper == GREATER_EQUAL: res = comp >= 0 + + return 2*res + + _internal_error("Internal error while evaluating expression: " + "unknown operation {}.".format(expr[0])) + +def expr_str(expr): + """ + Returns the string representation of the expression 'expr', as in a Kconfig + file. + + Passing subexpressions of expressions to this function works as expected. + """ + if isinstance(expr, Symbol): + if expr.is_constant: + return '"{}"'.format(escape(expr.name)) + return expr.name + + if isinstance(expr, Choice): + if expr.name is not None: + return "<choice {}>".format(expr.name) + return "<choice>" + + if expr[0] == NOT: + if isinstance(expr[1], tuple): + return "!({})".format(expr_str(expr[1])) + return "!" + expr_str(expr[1]) # Symbol + + if expr[0] == AND: + return "{} && {}".format(_parenthesize(expr[1], OR), + _parenthesize(expr[2], OR)) + + if expr[0] == OR: + # This turns A && B || C && D into "(A && B) || (C && D)", which is + # redundant, but more readable + return "{} || {}".format(_parenthesize(expr[1], AND), + _parenthesize(expr[2], AND)) + + # Relation + return "{} {} {}".format(expr_str(expr[1]), + _REL_TO_STR[expr[0]], + expr_str(expr[2])) + +def expr_items(expr): + """ + Returns a set() of all items (symbols and choices) that appear in the + expression 'expr'. + """ + + res = set() + + def rec(subexpr): + if isinstance(subexpr, tuple): + # AND, OR, NOT, or relation + + rec(subexpr[1]) + + # NOTs only have a single operand + if subexpr[0] != NOT: + rec(subexpr[2]) + + else: + # Symbol or choice + res.add(subexpr) + + rec(expr) + return res + +def split_expr(expr, op): + """ + Returns a list containing the top-level AND or OR operands in the + expression 'expr', in the same (left-to-right) order as they appear in + the expression. + + This can be handy e.g. for splitting (weak) reverse dependencies + from 'select' and 'imply' into individual selects/implies. + + op: + Either AND to get AND operands, or OR to get OR operands. + + (Having this as an operand might be more future-safe than having two + hardcoded functions.) + + + Pseudo-code examples: + + split_expr( A , OR ) -> [A] + split_expr( A && B , OR ) -> [A && B] + split_expr( A || B , OR ) -> [A, B] + split_expr( A || B , AND ) -> [A || B] + split_expr( A || B || (C && D) , OR ) -> [A, B, C && D] + + # Second || is not at the top level + split_expr( A || (B && (C || D)) , OR ) -> [A, B && (C || D)] + + # Parentheses don't matter as long as we stay at the top level (don't + # encounter any non-'op' nodes) + split_expr( (A || B) || C , OR ) -> [A, B, C] + split_expr( A || (B || C) , OR ) -> [A, B, C] + """ + res = [] + + def rec(subexpr): + if isinstance(subexpr, tuple) and subexpr[0] == op: + rec(subexpr[1]) + rec(subexpr[2]) + else: + res.append(subexpr) + + rec(expr) + return res + +def escape(s): + r""" + Escapes the string 's' in the same fashion as is done for display in + Kconfig format and when writing strings to a .config file. " and \ are + replaced by \" and \\, respectively. + """ + # \ must be escaped before " to avoid double escaping + return s.replace("\\", r"\\").replace('"', r'\"') + +# unescape() helper +_unescape_sub = re.compile(r"\\(.)").sub + +def unescape(s): + r""" + Unescapes the string 's'. \ followed by any character is replaced with just + that character. Used internally when reading .config files. + """ + return _unescape_sub(r"\1", s) + +def standard_kconfig(): + """ + Helper for tools. Loads the top-level Kconfig specified as the first + command-line argument, or "Kconfig" if there are no command-line arguments. + Returns the Kconfig instance. + + Exits with sys.exit() (which raises a SystemExit exception) and prints a + usage note to stderr if more than one command-line argument is passed. + """ + if len(sys.argv) > 2: + sys.exit("usage: {} [Kconfig]".format(sys.argv[0])) + + return Kconfig("Kconfig" if len(sys.argv) < 2 else sys.argv[1]) + +def standard_config_filename(): + """ + Helper for tools. Returns the value of KCONFIG_CONFIG (which specifies the + .config file to load/save) if it is set, and ".config" otherwise. + """ + return os.environ.get("KCONFIG_CONFIG", ".config") + +# +# Internal functions +# + +def _visibility(sc): + # Symbols and Choices have a "visibility" that acts as an upper bound on + # the values a user can set for them, corresponding to the visibility in + # e.g. 'make menuconfig'. This function calculates the visibility for the + # Symbol or Choice 'sc' -- the logic is nearly identical. + + vis = 0 + + for node in sc.nodes: + if node.prompt: + vis = max(vis, expr_value(node.prompt[1])) + + if isinstance(sc, Symbol) and sc.choice: + if sc.choice.orig_type == TRISTATE and sc.orig_type != TRISTATE and \ + sc.choice.tri_value != 2: + # Non-tristate choice symbols are only visible in y mode + return 0 + + if sc.orig_type == TRISTATE and vis == 1 and sc.choice.tri_value == 2: + # Choice symbols with m visibility are not visible in y mode + return 0 + + # Promote m to y if we're dealing with a non-tristate (possibly due to + # modules being disabled) + if vis == 1 and sc.type != TRISTATE: + return 2 + + return vis + +def _make_depend_on(sc, expr): + # Adds 'sc' (symbol or choice) as a "dependee" to all symbols in 'expr'. + # Constant symbols in 'expr' are skipped as they can never change value + # anyway. + + if isinstance(expr, tuple): + # AND, OR, NOT, or relation + + _make_depend_on(sc, expr[1]) + + # NOTs only have a single operand + if expr[0] != NOT: + _make_depend_on(sc, expr[2]) + + elif not expr.is_constant: + # Non-constant symbol, or choice + expr._dependents.add(sc) + +def _parenthesize(expr, type_): + # expr_str() helper. Adds parentheses around expressions of type 'type_'. + + if isinstance(expr, tuple) and expr[0] == type_: + return "({})".format(expr_str(expr)) + return expr_str(expr) + +def _indentation(line): + # Returns the length of the line's leading whitespace, treating tab stops + # as being spaced 8 characters apart. + + line = line.expandtabs() + return len(line) - len(line.lstrip()) + +def _is_base_n(s, n): + try: + int(s, n) + return True + except ValueError: + return False + +def _strcmp(s1, s2): + # strcmp()-alike that returns -1, 0, or 1 + + return (s1 > s2) - (s1 < s2) + +def _is_num(s): + # Returns True if the string 's' looks like a number. + # + # Internally, all operands in Kconfig are symbols, only undefined symbols + # (which numbers usually are) get their name as their value. + # + # Only hex numbers that start with 0x/0X are classified as numbers. + # Otherwise, symbols whose names happen to contain only the letters A-F + # would trigger false positives. + + try: + int(s) + except ValueError: + if not s.startswith(("0x", "0X")): + return False + + try: + int(s, 16) + except ValueError: + return False + + return True + +def _sym_to_num(sym): + # expr_value() helper for converting a symbol to a number. Raises + # ValueError for symbols that can't be converted. + + # For BOOL and TRISTATE, n/m/y count as 0/1/2. This mirrors 9059a3493ef + # ("kconfig: fix relational operators for bool and tristate symbols") in + # the C implementation. + return sym.tri_value if sym.orig_type in (BOOL, TRISTATE) else \ + int(sym.str_value, _TYPE_TO_BASE[sym.orig_type]) + +def _internal_error(msg): + raise InternalError( + msg + + "\nSorry! You may want to send an email to ulfalizer a.t Google's " + "email service to tell me about this. Include the message above and " + "the stack trace and describe what you were doing.") + +def _decoding_error(e, filename, macro_linenr=None): + # Gives the filename and context for UnicodeDecodeError's, which are a pain + # to debug otherwise. 'e' is the UnicodeDecodeError object. + # + # If the decoding error is for the output of a $(shell,...) command, + # macro_linenr holds the line number where it was run (the exact line + # number isn't available for decoding errors in files). + + if macro_linenr is None: + loc = filename + else: + loc = "output from macro at {}:{}".format(filename, macro_linenr) + + raise KconfigError( + "\n" + "Malformed {} in {}\n" + "Context: {}\n" + "Problematic data: {}\n" + "Reason: {}".format( + e.encoding, loc, + e.object[max(e.start - 40, 0):e.end + 40], + e.object[e.start:e.end], + e.reason)) + +def _name_and_loc(sc): + # Helper for giving the symbol/choice name and location(s) in e.g. warnings + + name = sc.name or "<choice>" + + if not sc.nodes: + return name + " (undefined)" + + return "{} (defined at {})".format( + name, + ", ".join("{}:{}".format(node.filename, node.linenr) + for node in sc.nodes)) + + +# Menu manipulation + +def _expr_depends_on(expr, sym): + # Reimplementation of expr_depends_symbol() from mconf.c. Used to determine + # if a submenu should be implicitly created. This also influences which + # items inside choice statements are considered choice items. + + if not isinstance(expr, tuple): + return expr is sym + + if expr[0] in (EQUAL, UNEQUAL): + # Check for one of the following: + # sym = m/y, m/y = sym, sym != n, n != sym + + left, right = expr[1:] + + if right is sym: + left, right = right, left + elif left is not sym: + return False + + return (expr[0] == EQUAL and right is sym.kconfig.m or \ + right is sym.kconfig.y) or \ + (expr[0] == UNEQUAL and right is sym.kconfig.n) + + return expr[0] == AND and \ + (_expr_depends_on(expr[1], sym) or + _expr_depends_on(expr[2], sym)) + +def _auto_menu_dep(node1, node2): + # Returns True if node2 has an "automatic menu dependency" on node1. If + # node2 has a prompt, we check its condition. Otherwise, we look directly + # at node2.dep. + + # If node2 has no prompt, use its menu node dependencies instead + return _expr_depends_on(node2.prompt[1] if node2.prompt else node2.dep, + node1.item) + +def _flatten(node): + # "Flattens" menu nodes without prompts (e.g. 'if' nodes and non-visible + # symbols with children from automatic menu creation) so that their + # children appear after them instead. This gives a clean menu structure + # with no unexpected "jumps" in the indentation. + + while node: + if node.list and not node.prompt: + last_node = node.list + while 1: + last_node.parent = node.parent + if not last_node.next: + break + last_node = last_node.next + + last_node.next = node.next + node.next = node.list + node.list = None + + node = node.next + +def _remove_ifs(node): + # Removes 'if' nodes (which can be recognized by MenuNode.item being None), + # which are assumed to already have been flattened. The C implementation + # doesn't bother to do this, but we expose the menu tree directly, and it + # makes it nicer to work with. + + first = node.list + while first and first.item is None: + first = first.next + + cur = first + while cur: + if cur.next and cur.next.item is None: + cur.next = cur.next.next + cur = cur.next + + node.list = first + +def _finalize_choice(node): + # Finalizes a choice, marking each symbol whose menu node has the choice as + # the parent as a choice symbol, and automatically determining types if not + # specified. + + choice = node.item + + cur = node.list + while cur: + if isinstance(cur.item, Symbol): + cur.item.choice = choice + choice.syms.append(cur.item) + cur = cur.next + + # If no type is specified for the choice, its type is that of + # the first choice item with a specified type + if choice.orig_type == UNKNOWN: + for item in choice.syms: + if item.orig_type != UNKNOWN: + choice.orig_type = item.orig_type + break + + # Each choice item of UNKNOWN type gets the type of the choice + for sym in choice.syms: + if sym.orig_type == UNKNOWN: + sym.orig_type = choice.orig_type + +def _check_dep_loop_sym(sym, ignore_choice): + # Detects dependency loops using depth-first search on the dependency graph + # (which is calculated earlier in Kconfig._build_dep()). + # + # Algorithm: + # + # 1. Symbols/choices start out with _checked = 0, meaning unvisited. + # + # 2. When a symbol/choice is first visited, _checked is set to 1, meaning + # "visited, potentially part of a dependency loop". The recursive + # search then continues from the symbol/choice. + # + # 3. If we run into a symbol/choice X with _checked already set to 1, + # there's a dependency loop. The loop is found on the call stack by + # recording symbols while returning ("on the way back") until X is seen + # again. + # + # 4. Once a symbol/choice and all its dependencies (or dependents in this + # case) have been checked recursively without detecting any loops, its + # _checked is set to 2, meaning "visited, not part of a dependency + # loop". + # + # This saves work if we run into the symbol/choice again in later calls + # to _check_dep_loop_sym(). We just return immediately. + # + # Choices complicate things, as every choice symbol depends on every other + # choice symbol in a sense. When a choice is "entered" via a choice symbol + # X, we visit all choice symbols from the choice except X, and prevent + # immediately revisiting the choice with a flag (ignore_choice). + # + # Maybe there's a better way to handle this (different flags or the + # like...) + + if not sym._checked: + # sym._checked == 0, unvisited + + sym._checked = 1 + + for dep in sym._dependents: + # Choices show up in Symbol._dependents when the choice has the + # symbol in a 'prompt' or 'default' condition (e.g. + # 'default ... if SYM'). + # + # Since we aren't entering the choice via a choice symbol, all + # choice symbols need to be checked, hence the None. + loop = _check_dep_loop_choice(dep, None) \ + if isinstance(dep, Choice) \ + else _check_dep_loop_sym(dep, False) + + if loop: + # Dependency loop found + return _found_dep_loop(loop, sym) + + if sym.choice and not ignore_choice: + loop = _check_dep_loop_choice(sym.choice, sym) + if loop: + # Dependency loop found + return _found_dep_loop(loop, sym) + + # The symbol is not part of a dependency loop + sym._checked = 2 + + # No dependency loop found + return None + + if sym._checked == 2: + # The symbol was checked earlier and is already known to not be part of + # a dependency loop + return None + + # sym._checked == 1, found a dependency loop. Return the symbol as the + # first element in it. + return (sym,) + +def _check_dep_loop_choice(choice, skip): + if not choice._checked: + # choice._checked == 0, unvisited + + choice._checked = 1 + + # Check for loops involving choice symbols. If we came here via a + # choice symbol, skip that one, as we'd get a false positive + # '<sym FOO> -> <choice> -> <sym FOO>' loop otherwise. + for sym in choice.syms: + if sym is not skip: + # Prevent the choice from being immediately re-entered via the + # "is a choice symbol" path by passing True + loop = _check_dep_loop_sym(sym, True) + if loop: + # Dependency loop found + return _found_dep_loop(loop, choice) + + # The choice is not part of a dependency loop + choice._checked = 2 + + # No dependency loop found + return None + + if choice._checked == 2: + # The choice was checked earlier and is already known to not be part of + # a dependency loop + return None + + # choice._checked == 1, found a dependency loop. Return the choice as the + # first element in it. + return (choice,) + +def _found_dep_loop(loop, cur): + # Called "on the way back" when we know we have a loop + + # Is the symbol/choice 'cur' where the loop started? + if cur is not loop[0]: + # Nope, it's just a part of the loop + return loop + (cur,) + + # Yep, we have the entire loop. Throw an exception that shows it. + + msg = "\nDependency loop\n" \ + "===============\n\n" + + for item in loop: + if item is not loop[0]: + msg += "...depends on " + if isinstance(item, Symbol) and item.choice: + msg += "the choice symbol " + + msg += "{}, with definition...\n\n{}\n" \ + .format(_name_and_loc(item), item) + + # Small wart: Since we reuse the already calculated + # Symbol/Choice._dependents sets for recursive dependency detection, we + # lose information on whether a dependency came from a 'select'/'imply' + # condition or e.g. a 'depends on'. + # + # This might cause selecting symbols to "disappear". For example, + # a symbol B having 'select A if C' gives a direct dependency from A to + # C, since it corresponds to a reverse dependency of B && C. + # + # Always print reverse dependencies for symbols that have them to make + # sure information isn't lost. I wonder if there's some neat way to + # improve this. + + if isinstance(item, Symbol): + if item.rev_dep is not item.kconfig.n: + msg += "(select-related dependencies: {})\n\n" \ + .format(expr_str(item.rev_dep)) + + if item.weak_rev_dep is not item.kconfig.n: + msg += "(imply-related dependencies: {})\n\n" \ + .format(expr_str(item.rev_dep)) + + msg += "...depends again on {}".format(_name_and_loc(loop[0])) + + raise KconfigError(msg) + +def _check_sym_sanity(sym): + # Checks various symbol properties that are handiest to check after + # parsing. Only generates errors and warnings. + + if sym.orig_type in (BOOL, TRISTATE): + # A helper function could be factored out here, but keep it + # speedy/straightforward for now. bool/tristate symbols are by far the + # most common, and most lack selects and implies. + + for target_sym, _ in sym.selects: + if target_sym.orig_type not in (BOOL, TRISTATE, UNKNOWN): + sym.kconfig._warn("{} selects the {} symbol {}, which is not " + "bool or tristate" + .format(_name_and_loc(sym), + TYPE_TO_STR[target_sym.orig_type], + _name_and_loc(target_sym))) + + for target_sym, _ in sym.implies: + if target_sym.orig_type not in (BOOL, TRISTATE, UNKNOWN): + sym.kconfig._warn("{} implies the {} symbol {}, which is not " + "bool or tristate" + .format(_name_and_loc(sym), + TYPE_TO_STR[target_sym.orig_type], + _name_and_loc(target_sym))) + + elif sym.orig_type in (STRING, INT, HEX): + for default, _ in sym.defaults: + if not isinstance(default, Symbol): + raise KconfigError( + "the {} symbol {} has a malformed default {} -- expected " + "a single symbol" + .format(TYPE_TO_STR[sym.orig_type], _name_and_loc(sym), + expr_str(default))) + + if sym.orig_type == STRING: + if not default.is_constant and not default.nodes and \ + not default.name.isupper(): + # 'default foo' on a string symbol could be either a symbol + # reference or someone leaving out the quotes. Guess that + # the quotes were left out if 'foo' isn't all-uppercase + # (and no symbol named 'foo' exists). + sym.kconfig._warn("style: quotes recommended around " + "default value for string symbol " + + _name_and_loc(sym)) + + elif sym.orig_type in (INT, HEX) and \ + not _int_hex_ok(default, sym.orig_type): + + sym.kconfig._warn("the {0} symbol {1} has a non-{0} default {2}" + .format(TYPE_TO_STR[sym.orig_type], + _name_and_loc(sym), + _name_and_loc(default))) + + if sym.selects or sym.implies: + sym.kconfig._warn("the {} symbol {} has selects or implies" + .format(TYPE_TO_STR[sym.orig_type], + _name_and_loc(sym))) + + else: # UNKNOWN + sym.kconfig._warn("{} defined without a type" + .format(_name_and_loc(sym))) + + + if sym.ranges: + if sym.orig_type not in (INT, HEX): + sym.kconfig._warn( + "the {} symbol {} has ranges, but is not int or hex" + .format(TYPE_TO_STR[sym.orig_type], _name_and_loc(sym))) + else: + for low, high, _ in sym.ranges: + if not _int_hex_ok(low, sym.orig_type) or \ + not _int_hex_ok(high, sym.orig_type): + + sym.kconfig._warn("the {0} symbol {1} has a non-{0} range " + "[{2}, {3}]" + .format(TYPE_TO_STR[sym.orig_type], + _name_and_loc(sym), + _name_and_loc(low), + _name_and_loc(high))) + + +def _int_hex_ok(sym, type_): + # Returns True if the (possibly constant) symbol 'sym' is valid as a value + # for a symbol of type type_ (INT or HEX) + + # 'not sym.nodes' implies a constant or undefined symbol, e.g. a plain + # "123" + if not sym.nodes: + return _is_base_n(sym.name, _TYPE_TO_BASE[type_]) + + return sym.orig_type == type_ + +def _check_choice_sanity(choice): + # Checks various choice properties that are handiest to check after + # parsing. Only generates errors and warnings. + + if choice.orig_type not in (BOOL, TRISTATE): + choice.kconfig._warn("{} defined with type {}" + .format(_name_and_loc(choice), + TYPE_TO_STR[choice.orig_type])) + + for node in choice.nodes: + if node.prompt: + break + else: + choice.kconfig._warn(_name_and_loc(choice) + + " defined without a prompt") + + for default, _ in choice.defaults: + if not isinstance(default, Symbol): + raise KconfigError( + "{} has a malformed default {}" + .format(_name_and_loc(choice), expr_str(default))) + + if default.choice is not choice: + choice.kconfig._warn("the default selection {} of {} is not " + "contained in the choice" + .format(_name_and_loc(default), + _name_and_loc(choice))) + + for sym in choice.syms: + if sym.defaults: + sym.kconfig._warn("default on the choice symbol {} will have " + "no effect".format(_name_and_loc(sym))) + + if sym.rev_dep is not sym.kconfig.n: + _warn_choice_select_imply(sym, sym.rev_dep, "selected") + + if sym.weak_rev_dep is not sym.kconfig.n: + _warn_choice_select_imply(sym, sym.weak_rev_dep, "implied") + + for node in sym.nodes: + if node.parent.item is choice: + if not node.prompt: + sym.kconfig._warn("the choice symbol {} has no prompt" + .format(_name_and_loc(sym))) + + elif node.prompt: + sym.kconfig._warn("the choice symbol {} is defined with a " + "prompt outside the choice" + .format(_name_and_loc(sym))) + +def _warn_choice_select_imply(sym, expr, expr_type): + msg = "the choice symbol {} is {} by the following symbols, which has " \ + "no effect: ".format(_name_and_loc(sym), expr_type) + + # si = select/imply + for si in split_expr(expr, OR): + msg += "\n - " + _name_and_loc(split_expr(si, AND)[0]) + + sym.kconfig._warn(msg) + +# Predefined preprocessor functions + +def _filename_fn(kconf, args): + return kconf._filename + +def _lineno_fn(kconf, args): + return str(kconf._linenr) + +def _info_fn(kconf, args): + print("{}:{}: {}".format(kconf._filename, kconf._linenr, args[1])) + + return "" + +def _warning_if_fn(kconf, args): + if args[1] == "y": + kconf._warn(args[2], kconf._filename, kconf._linenr) + + return "" + +def _error_if_fn(kconf, args): + if args[1] == "y": + raise KconfigError("{}:{}: {}".format( + kconf._filename, kconf._linenr, args[2])) + + return "" + +def _shell_fn(kconf, args): + # Use universal newlines mode to prevent e.g. stray \r's in command output + # on Windows + + if _IS_PY2: + # No decoding on Python 2 + stdout, stderr = subprocess.Popen( + args[1], shell=True, + stdout=subprocess.PIPE, stderr=subprocess.PIPE, + universal_newlines=True + ).communicate() + + else: + # Passing universal_newlines=True and/or 'encoding' on Python 3 turns + # on decoding of the output (bytes -> str), which might fail + try: + stdout, stderr = subprocess.Popen( + args[1], shell=True, + stdout=subprocess.PIPE, stderr=subprocess.PIPE, + universal_newlines=True, encoding=kconf._encoding + ).communicate() + except UnicodeDecodeError as e: + _decoding_error(e, kconf._filename, kconf._linenr) + + if stderr: + kconf._warn( + "'{}' wrote to stderr: {}".format(args[1], stderr.rstrip("\n")), + kconf._filename, kconf._linenr) + + return stdout.rstrip("\n").replace("\n", " ") + +# +# Public global constants +# + +# Integers representing symbol types +( + BOOL, + HEX, + INT, + STRING, + TRISTATE, + UNKNOWN +) = range(6) + +# Integers representing menu and comment menu nodes +( + MENU, + COMMENT, +) = range(2) + +# Converts a symbol/choice type to a string +TYPE_TO_STR = { + UNKNOWN: "unknown", + BOOL: "bool", + TRISTATE: "tristate", + STRING: "string", + HEX: "hex", + INT: "int", +} + +TRI_TO_STR = { + 0: "n", + 1: "m", + 2: "y", +} + +STR_TO_TRI = { + "n": 0, + "m": 1, + "y": 2, +} + +# +# Internal global constants (plus public expression type +# constants) +# + +# Are we running on Python 2? +_IS_PY2 = sys.version_info[0] < 3 + +# Tokens, with values 1, 2, ... . Avoiding 0 simplifies some checks by making +# all tokens except empty strings truthy. +( + _T_ALLNOCONFIG_Y, + _T_AND, + _T_BOOL, + _T_CHOICE, + _T_CLOSE_PAREN, + _T_COMMENT, + _T_CONFIG, + _T_DEFAULT, + _T_DEFCONFIG_LIST, + _T_DEF_BOOL, + _T_DEF_HEX, + _T_DEF_INT, + _T_DEF_STRING, + _T_DEF_TRISTATE, + _T_DEPENDS, + _T_ENDCHOICE, + _T_ENDIF, + _T_ENDMENU, + _T_ENV, + _T_EQUAL, + _T_GREATER, + _T_GREATER_EQUAL, + _T_HELP, + _T_HEX, + _T_IF, + _T_IMPLY, + _T_INT, + _T_LESS, + _T_LESS_EQUAL, + _T_MAINMENU, + _T_MENU, + _T_MENUCONFIG, + _T_MODULES, + _T_NOT, + _T_ON, + _T_OPEN_PAREN, + _T_OPTION, + _T_OPTIONAL, + _T_OR, + _T_ORSOURCE, + _T_OSOURCE, + _T_PROMPT, + _T_RANGE, + _T_RSOURCE, + _T_SELECT, + _T_SOURCE, + _T_STRING, + _T_TRISTATE, + _T_UNEQUAL, + _T_VISIBLE, +) = range(1, 51) + +# Public integers representing expression types +# +# Having these match the value of the corresponding tokens removes the need +# for conversion +AND = _T_AND +OR = _T_OR +NOT = _T_NOT +EQUAL = _T_EQUAL +UNEQUAL = _T_UNEQUAL +LESS = _T_LESS +LESS_EQUAL = _T_LESS_EQUAL +GREATER = _T_GREATER +GREATER_EQUAL = _T_GREATER_EQUAL + +# Keyword to token map, with the get() method assigned directly as a small +# optimization +_get_keyword = { + "---help---": _T_HELP, + "allnoconfig_y": _T_ALLNOCONFIG_Y, + "bool": _T_BOOL, + "boolean": _T_BOOL, + "choice": _T_CHOICE, + "comment": _T_COMMENT, + "config": _T_CONFIG, + "def_bool": _T_DEF_BOOL, + "def_hex": _T_DEF_HEX, + "def_int": _T_DEF_INT, + "def_string": _T_DEF_STRING, + "def_tristate": _T_DEF_TRISTATE, + "default": _T_DEFAULT, + "defconfig_list": _T_DEFCONFIG_LIST, + "depends": _T_DEPENDS, + "endchoice": _T_ENDCHOICE, + "endif": _T_ENDIF, + "endmenu": _T_ENDMENU, + "env": _T_ENV, + "grsource": _T_ORSOURCE, # Backwards compatibility + "gsource": _T_OSOURCE, # Backwards compatibility + "help": _T_HELP, + "hex": _T_HEX, + "if": _T_IF, + "imply": _T_IMPLY, + "int": _T_INT, + "mainmenu": _T_MAINMENU, + "menu": _T_MENU, + "menuconfig": _T_MENUCONFIG, + "modules": _T_MODULES, + "on": _T_ON, + "option": _T_OPTION, + "optional": _T_OPTIONAL, + "orsource": _T_ORSOURCE, + "osource": _T_OSOURCE, + "prompt": _T_PROMPT, + "range": _T_RANGE, + "rsource": _T_RSOURCE, + "select": _T_SELECT, + "source": _T_SOURCE, + "string": _T_STRING, + "tristate": _T_TRISTATE, + "visible": _T_VISIBLE, +}.get + +# Tokens after which strings are expected. This is used to tell strings from +# constant symbol references during tokenization, both of which are enclosed in +# quotes. +# +# Identifier-like lexemes ("missing quotes") are also treated as strings after +# these tokens. _T_CHOICE is included to avoid symbols being registered for +# named choices. +_STRING_LEX = frozenset(( + _T_BOOL, + _T_CHOICE, + _T_COMMENT, + _T_HEX, + _T_INT, + _T_MAINMENU, + _T_MENU, + _T_ORSOURCE, + _T_OSOURCE, + _T_PROMPT, + _T_RSOURCE, + _T_SOURCE, + _T_STRING, + _T_TRISTATE, +)) + +# Tokens for types, excluding def_bool, def_tristate, etc., for quick +# checks during parsing +_TYPE_TOKENS = frozenset(( + _T_BOOL, + _T_TRISTATE, + _T_INT, + _T_HEX, + _T_STRING, +)) + + +# Helper functions for getting compiled regular expressions, with the needed +# matching function returned directly as a small optimization. +# +# Use ASCII regex matching on Python 3. It's already the default on Python 2. + +def _re_match(regex): + return re.compile(regex, 0 if _IS_PY2 else re.ASCII).match + +def _re_search(regex): + return re.compile(regex, 0 if _IS_PY2 else re.ASCII).search + + +# Various regular expressions used during parsing + +# The initial token on a line. Also eats leading and trailing whitespace, so +# that we can jump straight to the next token (or to the end of the line if +# there is only one token). +# +# This regex will also fail to match for empty lines and comment lines. +# +# '$' is included to detect a variable assignment left-hand side with a $ in it +# (which might be from a macro expansion). +_command_match = _re_match(r"\s*([$A-Za-z0-9_-]+)\s*") + +# An identifier/keyword after the first token. Also eats trailing whitespace. +_id_keyword_match = _re_match(r"([A-Za-z0-9_/.-]+)\s*") + +# A fragment in the left-hand side of a preprocessor variable assignment. These +# are the portions between macro expansions ($(foo)). Macros are supported in +# the LHS (variable name). +_assignment_lhs_fragment_match = _re_match("[A-Za-z0-9_-]*") + +# The assignment operator and value (right-hand side) in a preprocessor +# variable assignment +_assignment_rhs_match = _re_match(r"\s*(=|:=|\+=)\s*(.*)") + +# Special characters/strings while expanding a macro (')', ',', and '$(') +_macro_special_search = _re_search(r"\)|,|\$\(") + +# Special characters/strings while expanding a string (quotes, '\', and '$(') +_string_special_search = _re_search(r'"|\'|\\|\$\(') + +# A valid right-hand side for an assignment to a string symbol in a .config +# file, including escaped characters. Extracts the contents. +_conf_string_match = _re_match(r'"((?:[^\\"]|\\.)*)"') + + +# Token to type mapping +_TOKEN_TO_TYPE = { + _T_BOOL: BOOL, + _T_DEF_BOOL: BOOL, + _T_DEF_HEX: HEX, + _T_DEF_INT: INT, + _T_DEF_STRING: STRING, + _T_DEF_TRISTATE: TRISTATE, + _T_HEX: HEX, + _T_INT: INT, + _T_STRING: STRING, + _T_TRISTATE: TRISTATE, +} + +# Constant representing that there's no cached choice selection. This is +# distinct from a cached None (no selection). We create a unique object (any +# will do) for it so we can test with 'is'. +_NO_CACHED_SELECTION = object() + +# Used in comparisons. 0 means the base is inferred from the format of the +# string. +_TYPE_TO_BASE = { + HEX: 16, + INT: 10, + STRING: 0, + UNKNOWN: 0, +} + +# Note: These constants deliberately equal the corresponding tokens (_T_EQUAL, +# _T_UNEQUAL, etc.), which removes the need for conversion +_RELATIONS = frozenset(( + EQUAL, + UNEQUAL, + LESS, + LESS_EQUAL, + GREATER, + GREATER_EQUAL, +)) + +_REL_TO_STR = { + EQUAL: "=", + UNEQUAL: "!=", + LESS: "<", + LESS_EQUAL: "<=", + GREATER: ">", + GREATER_EQUAL: ">=", +} |