1/* Copyright (C) 1997-2023 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#ifndef _GCONV_INT_H
19#define _GCONV_INT_H 1
20
21#include "gconv.h"
22#include <stdlib.h> /* For alloca used in macro below. */
23#include <ctype.h> /* For __toupper_l used in macro below. */
24#include <string.h> /* For strlen et al used in macro below. */
25#include <libc-lock.h>
26
27__BEGIN_DECLS
28
29
30/* Structure for alias definition. Simply two strings. */
31struct gconv_alias
32{
33 char *fromname;
34 char *toname;
35};
36
37
38/* Structure describing one loaded shared object. This normally are
39 objects to perform conversation but as a special case the db shared
40 object is also handled. */
41struct __gconv_loaded_object
42{
43 /* Name of the object. It must be the first structure element. */
44 const char *name;
45
46 /* Reference counter for the db functionality. If no conversion is
47 needed we unload the db library. */
48 int counter;
49
50 /* The handle for the shared object. */
51 void *handle;
52
53 /* Pointer to the functions the module defines. */
54 __gconv_fct fct;
55 __gconv_init_fct init_fct;
56 __gconv_end_fct end_fct;
57};
58
59
60/* Description for an available conversion module. */
61struct gconv_module
62{
63 const char *from_string;
64 const char *to_string;
65
66 int cost_hi;
67 int cost_lo;
68
69 const char *module_name;
70
71 struct gconv_module *left; /* Prefix smaller. */
72 struct gconv_module *same; /* List of entries with identical prefix. */
73 struct gconv_module *right; /* Prefix larger. */
74};
75
76
77/* The specification of the conversion that needs to be performed. */
78struct gconv_spec
79{
80 char *fromcode;
81 char *tocode;
82 bool translit;
83 bool ignore;
84};
85
86/* Flags for `gconv_open'. */
87enum
88{
89 GCONV_AVOID_NOCONV = 1 << 0
90};
91
92/* When GCONV_AVOID_NOCONV is set and no conversion is needed,
93 __GCONV_NULCONV should be returned. */
94enum
95{
96 __GCONV_NULCONV = -1
97};
98
99/* Global variables. */
100
101/* Database of alias names. */
102extern void *__gconv_alias_db attribute_hidden;
103
104/* Array with available modules. */
105extern struct gconv_module *__gconv_modules_db attribute_hidden;
106
107/* Value of the GCONV_PATH environment variable. */
108extern const char *__gconv_path_envvar attribute_hidden;
109
110/* Lock for the conversion database content. */
111__libc_lock_define (extern, __gconv_lock attribute_hidden)
112
113
114/* The gconv functions expects the name to be in upper case and complete,
115 including the trailing slashes if necessary. */
116#define norm_add_slashes(str,suffix) \
117 ({ \
118 const char *cp = (str); \
119 char *result; \
120 char *tmp; \
121 size_t cnt = 0; \
122 const size_t suffix_len = strlen (suffix); \
123 \
124 while (*cp != '\0') \
125 if (*cp++ == '/') \
126 ++cnt; \
127 \
128 tmp = result = __alloca (cp - (str) + 3 + suffix_len); \
129 cp = (str); \
130 while (*cp != '\0') \
131 *tmp++ = __toupper_l (*cp++, _nl_C_locobj_ptr); \
132 if (cnt < 2) \
133 { \
134 *tmp++ = '/'; \
135 if (cnt < 1) \
136 { \
137 *tmp++ = '/'; \
138 if (suffix_len != 0) \
139 tmp = __mempcpy (tmp, suffix, suffix_len); \
140 } \
141 } \
142 *tmp = '\0'; \
143 result; \
144 })
145
146
147/* Return in *HANDLE, a decriptor for the transformation. The function expects
148 the specification of the transformation in the structure pointed to by
149 CONV_SPEC. It only reads *CONV_SPEC and does not take ownership of it. */
150extern int __gconv_open (struct gconv_spec *conv_spec,
151 __gconv_t *handle, int flags);
152libc_hidden_proto (__gconv_open)
153
154/* This function accepts the charset names of the source and destination of the
155 conversion and populates *conv_spec with an equivalent conversion
156 specification that may later be used by __gconv_open. The charset names
157 might contain options in the form of suffixes that alter the conversion,
158 e.g. "ISO-10646/UTF-8/TRANSLIT". It processes the charset names, ignoring
159 and truncating any suffix options in fromcode, and processing and truncating
160 any suffix options in tocode. Supported suffix options ("TRANSLIT" or
161 "IGNORE") when found in tocode lead to the corresponding flag in *conv_spec
162 to be set to true. Unrecognized suffix options are silently discarded. If
163 the function succeeds, it returns conv_spec back to the caller. It returns
164 NULL upon failure. */
165extern struct gconv_spec *
166__gconv_create_spec (struct gconv_spec *conv_spec, const char *fromcode,
167 const char *tocode);
168libc_hidden_proto (__gconv_create_spec)
169
170/* This function frees all heap memory allocated by __gconv_create_spec. */
171extern void
172__gconv_destroy_spec (struct gconv_spec *conv_spec);
173libc_hidden_proto (__gconv_destroy_spec)
174
175/* Free resources associated with transformation descriptor CD. */
176extern int __gconv_close (__gconv_t cd)
177 attribute_hidden;
178
179/* Transform at most *INBYTESLEFT bytes from buffer starting at *INBUF
180 according to rules described by CD and place up to *OUTBYTESLEFT
181 bytes in buffer starting at *OUTBUF. Return number of non-identical
182 conversions in *IRREVERSIBLE if this pointer is not null. */
183extern int __gconv (__gconv_t cd, const unsigned char **inbuf,
184 const unsigned char *inbufend, unsigned char **outbuf,
185 unsigned char *outbufend, size_t *irreversible)
186 attribute_hidden;
187
188/* Return in *HANDLE a pointer to an array with *NSTEPS elements describing
189 the single steps necessary for transformation from FROMSET to TOSET. */
190extern int __gconv_find_transform (const char *toset, const char *fromset,
191 struct __gconv_step **handle,
192 size_t *nsteps, int flags)
193 attribute_hidden;
194
195/* Search for transformation in cache data. */
196extern int __gconv_lookup_cache (const char *toset, const char *fromset,
197 struct __gconv_step **handle, size_t *nsteps,
198 int flags)
199 attribute_hidden;
200
201/* Compare the two name for whether they are after alias expansion the
202 same. This function uses the cache and fails if none is
203 loaded. */
204extern int __gconv_compare_alias_cache (const char *name1, const char *name2,
205 int *result)
206 attribute_hidden;
207
208/* Free data associated with a step's structure. */
209extern void __gconv_release_step (struct __gconv_step *step)
210 attribute_hidden;
211
212/* Read all the configuration data and cache it if not done so already. */
213extern void __gconv_load_conf (void) attribute_hidden;
214
215/* Try to read module cache file. */
216extern int __gconv_load_cache (void) attribute_hidden;
217
218/* Retrieve pointer to internal cache. */
219extern void *__gconv_get_cache (void);
220
221/* Retrieve pointer to internal module database. */
222extern struct gconv_module *__gconv_get_modules_db (void);
223
224/* Retrieve pointer to internal alias database. */
225extern void *__gconv_get_alias_db (void);
226
227/* Comparison function to search alias. */
228extern int __gconv_alias_compare (const void *p1, const void *p2)
229 attribute_hidden;
230
231/* Clear reference to transformation step implementations which might
232 cause the code to be unloaded. */
233extern int __gconv_close_transform (struct __gconv_step *steps,
234 size_t nsteps)
235 attribute_hidden;
236
237/* Free all resources allocated for the transformation record when
238 using the cache. */
239extern void __gconv_release_cache (struct __gconv_step *steps, size_t nsteps)
240 attribute_hidden;
241
242/* Load shared object named by NAME. If already loaded increment reference
243 count. */
244extern struct __gconv_loaded_object *__gconv_find_shlib (const char *name)
245 attribute_hidden;
246
247/* Release shared object. If no further reference is available unload
248 the object. */
249extern void __gconv_release_shlib (struct __gconv_loaded_object *handle)
250 attribute_hidden;
251
252/* Fill STEP with information about builtin module with NAME. */
253extern void __gconv_get_builtin_trans (const char *name,
254 struct __gconv_step *step)
255 attribute_hidden;
256
257/* Transliteration using the locale's data. */
258extern int __gconv_transliterate (struct __gconv_step *step,
259 struct __gconv_step_data *step_data,
260 const unsigned char *inbufstart,
261 const unsigned char **inbufp,
262 const unsigned char *inbufend,
263 unsigned char **outbufstart,
264 size_t *irreversible);
265libc_hidden_proto (__gconv_transliterate)
266
267/* If NAME is an codeset alias expand it. */
268extern int __gconv_compare_alias (const char *name1, const char *name2)
269 attribute_hidden;
270
271
272/* Builtin transformations. */
273#ifdef _LIBC
274# define __BUILTIN_TRANSFORM(Name) \
275 extern int Name (struct __gconv_step *step, \
276 struct __gconv_step_data *data, \
277 const unsigned char **inbuf, \
278 const unsigned char *inbufend, \
279 unsigned char **outbufstart, size_t *irreversible, \
280 int do_flush, int consume_incomplete)
281
282__BUILTIN_TRANSFORM (__gconv_transform_ascii_internal);
283__BUILTIN_TRANSFORM (__gconv_transform_internal_ascii);
284__BUILTIN_TRANSFORM (__gconv_transform_utf8_internal);
285__BUILTIN_TRANSFORM (__gconv_transform_internal_utf8);
286__BUILTIN_TRANSFORM (__gconv_transform_ucs2_internal);
287__BUILTIN_TRANSFORM (__gconv_transform_internal_ucs2);
288__BUILTIN_TRANSFORM (__gconv_transform_ucs2reverse_internal);
289__BUILTIN_TRANSFORM (__gconv_transform_internal_ucs2reverse);
290__BUILTIN_TRANSFORM (__gconv_transform_internal_ucs4);
291__BUILTIN_TRANSFORM (__gconv_transform_ucs4_internal);
292__BUILTIN_TRANSFORM (__gconv_transform_internal_ucs4le);
293__BUILTIN_TRANSFORM (__gconv_transform_ucs4le_internal);
294__BUILTIN_TRANSFORM (__gconv_transform_internal_utf16);
295__BUILTIN_TRANSFORM (__gconv_transform_utf16_internal);
296# undef __BUITLIN_TRANSFORM
297
298/* Specialized conversion function for a single byte to INTERNAL, recognizing
299 only ASCII characters. */
300extern wint_t __gconv_btwoc_ascii (struct __gconv_step *step, unsigned char c);
301
302#endif
303
304__END_DECLS
305
306#endif /* gconv_int.h */
307