Ruby: ext/digest/bubblebabble/bubblebabble.c Source File

Ruby 3.0.5p211 (2022-11-24 revision ba5cf0f7c52d4d35cc6a173c89eda98ceffa2dcf)

bubblebabble.c
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1/************************************************
2
3 bubblebabble.c - BubbleBabble encoding support
4
5 $Author$
6 created at: Fri Oct 13 18:31:42 JST 2006
7
8 Copyright (C) 2006 Akinori MUSHA
9
10 $Id$
11
12************************************************/
13
14#include <ruby/ruby.h>
15#include "../digest.h"
16
17static ID id_digest;
18
19static VALUE
20bubblebabble_str_new(VALUE str_digest)
21{
22 char *digest;
23 size_t digest_len;
24 VALUE str;
25 char *p;
26 size_t i, j, seed = 1;
27 static const char vowels[] = {
28 'a', 'e', 'i', 'o', 'u', 'y'
29 };
30 static const char consonants[] = {
31 'b', 'c', 'd', 'f', 'g', 'h', 'k', 'l', 'm', 'n',
32 'p', 'r', 's', 't', 'v', 'z', 'x'
33 };
34
35 StringValue(str_digest);
36 digest = RSTRING_PTR(str_digest);
37 digest_len = RSTRING_LEN(str_digest);
38
39 if ((LONG_MAX - 2) / 3 < (digest_len | 1)) {
40 rb_raise(rb_eRuntimeError, "digest string too long");
41 }
42
43 str = rb_str_new(0, (digest_len | 1) * 3 + 2);
44 p = RSTRING_PTR(str);
45
46 i = j = 0;
47 p[j++] = 'x';
48
49 for (;;) {
50 unsigned char byte1, byte2;
51
52 if (i >= digest_len) {
53 p[j++] = vowels[seed % 6];
54 p[j++] = consonants[16];
55 p[j++] = vowels[seed / 6];
56 break;
57 }
58
59 byte1 = digest[i++];
60 p[j++] = vowels[(((byte1 >> 6) & 3) + seed) % 6];
61 p[j++] = consonants[(byte1 >> 2) & 15];
62 p[j++] = vowels[((byte1 & 3) + (seed / 6)) % 6];
63
64 if (i >= digest_len) {
65 break;
66 }
67
68 byte2 = digest[i++];
69 p[j++] = consonants[(byte2 >> 4) & 15];
70 p[j++] = '-';
71 p[j++] = consonants[byte2 & 15];
72
73 seed = (seed * 5 + byte1 * 7 + byte2) % 36;
74 }
75
76 p[j] = 'x';
77
78 return str;
79}
80
81/* Document-method: Digest::bubblebabble
82 *
83 * call-seq:
84 * Digest.bubblebabble(string) -> bubblebabble_string
85 *
86 * Returns a BubbleBabble encoded version of a given _string_.
87 */
88static VALUE
89rb_digest_s_bubblebabble(VALUE klass, VALUE str)
90{
91 return bubblebabble_str_new(str);
92}
93
94/* Document-method: Digest::Class::bubblebabble
95 *
96 * call-seq:
97 * Digest::Class.bubblebabble(string, ...) -> hash_string
98 *
99 * Returns the BubbleBabble encoded hash value of a given _string_.
100 */
101static VALUE
102rb_digest_class_s_bubblebabble(int argc, VALUE *argv, VALUE klass)
103{
104 return bubblebabble_str_new(rb_funcallv(klass, id_digest, argc, argv));
105}
106
107/* Document-method: Digest::Instance#bubblebabble
108 *
109 * call-seq:
110 * digest_obj.bubblebabble -> hash_string
111 *
112 * Returns the resulting hash value in a Bubblebabble encoded form.
113 */
114static VALUE
115rb_digest_instance_bubblebabble(VALUE self)
116{
117 return bubblebabble_str_new(rb_funcall(self, id_digest, 0));
118}
119
120/*
121 * This module adds some methods to Digest classes to perform
122 * BubbleBabble encoding.
123 */
124void
125Init_bubblebabble(void)
126{
127#undef rb_intern
128 VALUE rb_mDigest, rb_mDigest_Instance, rb_cDigest_Class;
129
130 rb_require("digest");
131
132 rb_mDigest = rb_path2class("Digest");
133 rb_mDigest_Instance = rb_path2class("Digest::Instance");
134 rb_cDigest_Class = rb_path2class("Digest::Class");
135
136#if 0
137 rb_mDigest = rb_define_module("Digest");
138 rb_mDigest_Instance = rb_define_module_under(rb_mDigest, "Instance");
139 rb_cDigest_Class = rb_define_class_under(rb_mDigest, "Class", rb_cObject);
140#endif
141
142 rb_define_module_function(rb_mDigest, "bubblebabble", rb_digest_s_bubblebabble, 1);
143 rb_define_singleton_method(rb_cDigest_Class, "bubblebabble", rb_digest_class_s_bubblebabble, -1);
144 rb_define_method(rb_mDigest_Instance, "bubblebabble", rb_digest_instance_bubblebabble, 0);
145
146 id_digest = rb_intern("digest");
147}
Init_bubblebabble
void Init_bubblebabble(void)
Definition: bubblebabble.c:125
rb_define_method
#define rb_define_method(klass, mid, func, arity)
Defines klass#mid.
Definition: cxxanyargs.hpp:653
rb_define_singleton_method
#define rb_define_singleton_method(klass, mid, func, arity)
Defines klass.mid.
Definition: cxxanyargs.hpp:668
rb_define_module_function
#define rb_define_module_function(klass, mid, func, arity)
Defines klass#mid and makes it a module function.
Definition: cxxanyargs.hpp:672
str
char str[HTML_ESCAPE_MAX_LEN+1]
Definition: escape.c:18
RSTRING_LEN
#define RSTRING_LEN(string)
Definition: fbuffer.h:22
RSTRING_PTR
#define RSTRING_PTR(string)
Definition: fbuffer.h:19
rb_define_class_under
VALUE rb_define_class_under(VALUE outer, const char *name, VALUE super)
Defines a class under the namespace of outer.
Definition: class.c:797
rb_define_module
VALUE rb_define_module(const char *name)
Definition: class.c:871
rb_define_module_under
VALUE rb_define_module_under(VALUE outer, const char *name)
Definition: class.c:895
rb_raise
void rb_raise(VALUE exc, const char *fmt,...)
Definition: error.c:2917
rb_eRuntimeError
VALUE rb_eRuntimeError
Definition: error.c:1055
rb_cObject
VALUE rb_cObject
Object class.
Definition: object.c:49
rb_funcall
VALUE rb_funcall(VALUE, ID, int,...)
Calls a method.
Definition: vm_eval.c:1077
rb_str_new
#define rb_str_new(str, len)
Definition: string.h:213
rb_path2class
VALUE rb_path2class(const char *)
Definition: variable.c:287
rb_intern
ID rb_intern(const char *)
Definition: symbol.c:785
rb_funcallv
#define rb_funcallv(...)
Definition: internal.h:77
LONG_MAX
#define LONG_MAX
Definition: limits.h:36
StringValue
#define StringValue(v)
Definition: rstring.h:50
ruby.h
rb_require
VALUE rb_require(const char *)
Definition: load.c:1199
argc
int argc
Definition: ruby.c:240
argv
char ** argv
Definition: ruby.c:241
VALUE
unsigned long VALUE
Definition: value.h:38
ID
unsigned long ID
Definition: value.h:39