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Diffstat (limited to 'ext/digest/bubblebabble/bubblebabble.c')
-rw-r--r--ext/digest/bubblebabble/bubblebabble.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/ext/digest/bubblebabble/bubblebabble.c b/ext/digest/bubblebabble/bubblebabble.c
new file mode 100644
index 00000000000..1e882cce0e5
--- /dev/null
+++ b/ext/digest/bubblebabble/bubblebabble.c
@@ -0,0 +1,136 @@
+/************************************************
+
+ bubblebabble.c - BubbleBabble encoding support
+
+ $Author$
+ created at: Fri Oct 13 18:31:42 JST 2006
+
+ Copyright (C) 2006 Akinori MUSHA
+
+ $Id$
+
+************************************************/
+
+#include "ruby.h"
+
+static VALUE mDigest, cDigest_Base;
+static ID id_digest;
+
+static VALUE
+bubblebabble_str_new(VALUE str_digest)
+{
+ char *digest;
+ size_t digest_len;
+ VALUE str;
+ char *p;
+ int i, j, seed = 1;
+ static const char vowels[] = {
+ 'a', 'e', 'i', 'o', 'u', 'y'
+ };
+ static const char consonants[] = {
+ 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm', 'n',
+ 'p', 'r', 's', 't', 'v', 'z', 'x'
+ };
+
+ StringValue(str_digest);
+ digest = RSTRING_PTR(str_digest);
+ digest_len = RSTRING_LEN(str_digest);
+
+ if ((LONG_MAX - 2) / 3 < (digest_len | 1)) {
+ rb_raise(rb_eRuntimeError, "digest string too long");
+ }
+
+ str = rb_str_new(0, (digest_len | 1) * 3 + 2);
+ p = RSTRING_PTR(str);
+
+ i = j = 0;
+ p[j++] = 'x';
+
+ for (;;) {
+ unsigned char byte1, byte2;
+
+ if (i >= digest_len) {
+ p[j++] = vowels[seed % 6];
+ p[j++] = consonants[16];
+ p[j++] = vowels[seed / 6];
+ break;
+ }
+
+ byte1 = digest[i++];
+ p[j++] = vowels[(((byte1 >> 6) & 3) + seed) % 6];
+ p[j++] = consonants[(byte1 >> 2) & 15];
+ p[j++] = vowels[((byte1 & 3) + (seed / 6)) % 6];
+
+ if (i >= digest_len) {
+ break;
+ }
+
+ byte2 = digest[i++];
+ p[j++] = consonants[(byte2 >> 4) & 15];
+ p[j++] = '-';
+ p[j++] = consonants[byte2 & 15];
+
+ seed = (seed * 5 + byte1 * 7 + byte2) % 36;
+ }
+
+ p[j] = 'x';
+
+ return str;
+}
+
+/*
+ * call-seq:
+ * Digest.bubblebabble(string) -> bubblebabble_string
+ *
+ * Returns a BubbleBabble encoded version of a given _string_. */
+static VALUE
+rb_digest_s_bubblebabble(VALUE klass, VALUE str)
+{
+ return bubblebabble_str_new(str);
+}
+
+/*
+ * call-seq:
+ * Digest::ALGORITHM.bubblebabble(string) -> hash_string
+ *
+ * Returns the BubbleBabble encoded hash value of a given _string_.
+ */
+static VALUE
+rb_digest_base_s_bubblebabble(VALUE klass, VALUE str)
+{
+ return bubblebabble_str_new(rb_funcall(klass, id_digest, 1, str));
+}
+
+/*
+ * call-seq:
+ * digest_obj.bubblebabble -> hash_string
+ *
+ * Returns the resulting hash value in a Bubblebabble encoded form.
+ */
+static VALUE
+rb_digest_base_bubblebabble(VALUE self)
+{
+ return bubblebabble_str_new(rb_funcall(self, id_digest, 0));
+}
+
+/*
+ * This module adds some methods to Digest classes to perform
+ * BubbleBabble encoding.
+ */
+void
+Init_bubblebabble(void)
+{
+ mDigest = rb_define_module("Digest");
+ cDigest_Base = rb_define_class_under(mDigest, "Base", rb_cObject);
+
+ /* Digest::bubblebabble() */
+ rb_define_module_function(mDigest, "bubblebabble", rb_digest_s_bubblebabble, 1);
+
+ /* Digest::Base::bubblebabble() */
+ rb_define_singleton_method(cDigest_Base, "bubblebabble", rb_digest_base_s_bubblebabble, 1);
+
+ /* Digest::Base#bubblebabble() */
+ rb_define_method(cDigest_Base, "bubblebabble", rb_digest_base_bubblebabble, 0);
+
+ id_digest = rb_intern("digest");
+}