refactored ebus code

1 files changed, 81 insertions, 0 deletions

diff --git a/ebus-racket/3rdparty/zitterbewegung/uuid/uuid-v4.ss b/ebus-racket/3rdparty/zitterbewegung/uuid/uuid-v4.ss
new file mode 100644
index 0000000..9aa6aa4
--- /dev/null
+++ b/ebus-racket/3rdparty/zitterbewegung/uuid/uuid-v4.ss
@@ -0,0 +1,81 @@
+#lang scheme
+
+(require srfi/27)
+
+;;From Gambit Scheme Released under the LGPL
+;; UUID generation
+;; See: http://www.ietf.org/rfc/rfc4122.txt
+;;
+;; Version 4 UUID, see section 4.4
+(provide make-uuid
+         urn)
+(define random-integer-65536
+  (let* ((rs (make-random-source))
+         (ri (random-source-make-integers rs)))
+    (random-source-randomize! rs)
+	(lambda ()
+	  (ri 65536))))
+
+(define (make-uuid)
+  (define hex
+    '#(#\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7 #\8 #\9 #\A #\B #\C #\D #\E #\F))
+  (let ((n1 (random-integer-65536))
+        (n2 (random-integer-65536))
+        (n3 (random-integer-65536))
+        (n4 (random-integer-65536))
+        (n5 (random-integer-65536))
+        (n6 (random-integer-65536))
+        (n7 (random-integer-65536))
+        (n8 (random-integer-65536)))
+    (string->symbol
+     (string
+      ;; time_lo
+      (vector-ref hex (extract-bit-field 4 12 n1))
+      (vector-ref hex (extract-bit-field 4  8 n1))
+      (vector-ref hex (extract-bit-field 4  4 n1))
+      (vector-ref hex (extract-bit-field 4  0 n1))
+      (vector-ref hex (extract-bit-field 4 12 n2))
+      (vector-ref hex (extract-bit-field 4  8 n2))
+      (vector-ref hex (extract-bit-field 4  4 n2))
+      (vector-ref hex (extract-bit-field 4  0 n2))
+      #\-
+      ;; time_mid
+      (vector-ref hex (extract-bit-field 4 12 n3))
+      (vector-ref hex (extract-bit-field 4  8 n3))
+      (vector-ref hex (extract-bit-field 4  4 n3))
+      (vector-ref hex (extract-bit-field 4  0 n3))
+      #\-
+      ;; time_hi_and_version
+      (vector-ref hex #b0100)
+      (vector-ref hex (extract-bit-field 4  8 n4))
+      (vector-ref hex (extract-bit-field 4  4 n4))
+      (vector-ref hex (extract-bit-field 4  0 n4))
+      #\-
+      ;; clock_seq_hi_and_reserved
+      (vector-ref hex (bitwise-ior (extract-bit-field 2 12 n5) #b1000))
+      (vector-ref hex (extract-bit-field 4  8 n5))
+      ;; clock_seq_low
+      (vector-ref hex (extract-bit-field 4  4 n5))
+      (vector-ref hex (extract-bit-field 4  0 n5))
+      #\-
+      ;; node
+      (vector-ref hex (extract-bit-field 4 12 n6))
+      (vector-ref hex (extract-bit-field 4  8 n6))
+      (vector-ref hex (extract-bit-field 4  4 n6))
+      (vector-ref hex (extract-bit-field 4  0 n6))
+      (vector-ref hex (extract-bit-field 4 12 n7))
+      (vector-ref hex (extract-bit-field 4  8 n7))
+      (vector-ref hex (extract-bit-field 4  4 n7))
+      (vector-ref hex (extract-bit-field 4  0 n7))
+      (vector-ref hex (extract-bit-field 4 12 n8))
+      (vector-ref hex (extract-bit-field 4  8 n8))
+      (vector-ref hex (extract-bit-field 4  4 n8))
+      (vector-ref hex (extract-bit-field 4  0 n8))))))
+
+(define (extract-bit-field size position n)
+  (bitwise-and (bitwise-not (arithmetic-shift -1 size))
+               (arithmetic-shift n (- position))))
+
+(define (urn)
+  (string-append "urn:uuid:"
+                 (symbol->string (make-uuid))))