1 /*
2 * Copyright (c) 2003-2004, Artem B. Bityuckiy
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25 #define _DEFAULT_SOURCE
26 #include <_ansi.h>
27 #include <newlib.h>
28 #include <sys/types.h>
29 #include <string.h>
30 #include <stdlib.h>
31 #include <errno.h>
32 #include <ctype.h>
33 #include <sys/iconvnls.h>
34 #include "local.h"
35
36 /*
37 * canonical_form - canonize 'str'.
38 *
39 * PARAMETERS:
40 * const char *str - string to canonize.
41 *
42 * DESCRIPTION:
43 * Converts all letters to small and substitute all '-' characters by '_'
44 * characters.
45 *
46 * RETURN:
47 * Returns canonical form of 'str' if success, NULL if failure.
48 */
49 static const char *
canonical_form(const char * str)50 canonical_form (
51 const char *str)
52 {
53 char *p, *p1;
54
55 if (str == NULL || (p = p1 = strdup (str)) == NULL)
56 return (const char *)NULL;
57
58 for (; *str; str++, p++)
59 {
60 if (*str == '-')
61 *p = '_';
62 else
63 *p = tolower (*str);
64 }
65
66 return (const char *)p1;
67 }
68
69 /*
70 * find_alias - find encoding name name by it's alias.
71 *
72 * PARAMETERS:
73 * const char *alias - alias by which "official" name should be found.
74 * const char *table - aliases table.
75 * int len - aliases table length.
76 *
77 * DESCRIPTION:
78 * 'table' contains the list of encoding names and aliases.
79 * Names go first, e.g.:
80 *
81 * name1 alias11 alias12 alias1N
82 * name2 alias21 alias22 alias2N
83 * nameM aliasM1 aliasM2 aliasMN
84 *
85 * If line begins with backspace it is considered as the continuation of
86 * previous line.
87 *
88 * RETURN:
89 * Returns pointer to name found if success. In case of error returns NULL
90 * and sets current thread's/process's errno.
91 */
92 static char *
find_alias(const char * alias,const char * table,int len)93 find_alias (
94 const char *alias,
95 const char *table,
96 int len)
97 {
98 const char *end;
99 const char *p;
100 int l = strlen (alias);
101 const char *ptable = table;
102 const char *table_end = table + len;
103
104 if (table == NULL || alias == NULL || *table == '\0' || *alias == '\0')
105 return NULL;
106
107 search_again:
108 if (len < l || (p = strnstr (ptable, alias, len)) == NULL)
109 return NULL;
110
111 /* Check that substring is segregated by '\n', '\t' or ' ' */
112 if (!((p == table || isspace (*(p-1)) || *(p-1) == '\n')
113 && (p+l == table_end || isspace (*(p+l)) || *(p+l) == '\n')))
114 {
115 ptable = p + l;
116 len = table_end - ptable;
117 goto search_again;
118 }
119
120 while(--p > table && *p != '\n');
121
122 if (*(++p) == '#')
123 return NULL;
124
125 for (end = p + 1; !isspace (*end) && *end != '\n' && *end != '\0'; end++);
126
127 return strndup (p, (size_t)(end - p));
128 }
129
130 /*
131 * _iconv_resolve_encoding_name - resolves encoding's name by given alias.
132 *
133 * PARAMETERS:
134 * const char *ca - encoding alias to resolve.
135 *
136 * DESCRIPTION:
137 * First, tries to find 'ca' among built-in aliases. If not found, tries to
138 * find it external file.
139 *
140 * RETURN:
141 * Encoding name if found. In case of error returns NULL
142 * and sets current thread's/process's errno.
143 */
144 char *
_iconv_resolve_encoding_name(const char * ca)145 _iconv_resolve_encoding_name (
146 const char *ca)
147 {
148 char *p = (char *)ca;
149
150 /* Alias shouldn't contain white spaces, '\n' and '\r' symbols */
151 while (*p)
152 if (*p == ' ' || *p == '\r' || *p++ == '\n')
153 return NULL;
154
155 if ((ca = canonical_form (ca)) == NULL)
156 return NULL;
157
158 p = find_alias (ca, _iconv_aliases, strlen (_iconv_aliases));
159
160 free ((void *)ca);
161 return p;
162 }
163
164
