1/* Copyright (C) 1997-2021 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#ifndef _GCONV_INT_H
20#define _GCONV_INT_H 1
21
22#include "gconv.h"
23#include <stdlib.h> /* For alloca used in macro below. */
24#include <ctype.h> /* For __toupper_l used in macro below. */
25#include <string.h> /* For strlen et al used in macro below. */
26#include <libc-lock.h>
27
28__BEGIN_DECLS
29
30
31/* Structure for alias definition. Simply two strings. */
32struct gconv_alias
33{
34 char *fromname;
35 char *toname;
36};
37
38
39/* Structure describing one loaded shared object. This normally are
40 objects to perform conversation but as a special case the db shared
41 object is also handled. */
42struct __gconv_loaded_object
43{
44 /* Name of the object. It must be the first structure element. */
45 const char *name;
46
47 /* Reference counter for the db functionality. If no conversion is
48 needed we unload the db library. */
49 int counter;
50
51 /* The handle for the shared object. */
52 void *handle;
53
54 /* Pointer to the functions the module defines. */
55 __gconv_fct fct;
56 __gconv_init_fct init_fct;
57 __gconv_end_fct end_fct;
58};
59
60
61/* Description for an available conversion module. */
62struct gconv_module
63{
64 const char *from_string;
65 const char *to_string;
66
67 int cost_hi;
68 int cost_lo;
69
70 const char *module_name;
71
72 struct gconv_module *left; /* Prefix smaller. */
73 struct gconv_module *same; /* List of entries with identical prefix. */
74 struct gconv_module *right; /* Prefix larger. */
75};
76
77
78/* The specification of the conversion that needs to be performed. */
79struct gconv_spec
80{
81 char *fromcode;
82 char *tocode;
83 bool translit;
84 bool ignore;
85};
86
87/* Flags for `gconv_open'. */
88enum
89{
90 GCONV_AVOID_NOCONV = 1 << 0
91};
92
93/* When GCONV_AVOID_NOCONV is set and no conversion is needed,
94 __GCONV_NULCONV should be returned. */
95enum
96{
97 __GCONV_NULCONV = -1
98};
99
100/* Global variables. */
101
102/* Database of alias names. */
103extern void *__gconv_alias_db attribute_hidden;
104
105/* Array with available modules. */
106extern struct gconv_module *__gconv_modules_db attribute_hidden;
107
108/* Value of the GCONV_PATH environment variable. */
109extern const char *__gconv_path_envvar attribute_hidden;
110
111/* Lock for the conversion database content. */
112__libc_lock_define (extern, __gconv_lock attribute_hidden)
113
114
115/* The gconv functions expects the name to be in upper case and complete,
116 including the trailing slashes if necessary. */
117#define norm_add_slashes(str,suffix) \
118 ({ \
119 const char *cp = (str); \
120 char *result; \
121 char *tmp; \
122 size_t cnt = 0; \
123 const size_t suffix_len = strlen (suffix); \
124 \
125 while (*cp != '\0') \
126 if (*cp++ == '/') \
127 ++cnt; \
128 \
129 tmp = result = __alloca (cp - (str) + 3 + suffix_len); \
130 cp = (str); \
131 while (*cp != '\0') \
132 *tmp++ = __toupper_l (*cp++, _nl_C_locobj_ptr); \
133 if (cnt < 2) \
134 { \
135 *tmp++ = '/'; \
136 if (cnt < 1) \
137 { \
138 *tmp++ = '/'; \
139 if (suffix_len != 0) \
140 tmp = __mempcpy (tmp, suffix, suffix_len); \
141 } \
142 } \
143 *tmp = '\0'; \
144 result; \
145 })
146
147
148/* Return in *HANDLE, a decriptor for the transformation. The function expects
149 the specification of the transformation in the structure pointed to by
150 CONV_SPEC. It only reads *CONV_SPEC and does not take ownership of it. */
151extern int __gconv_open (struct gconv_spec *conv_spec,
152 __gconv_t *handle, int flags);
153libc_hidden_proto (__gconv_open)
154
155/* This function accepts the charset names of the source and destination of the
156 conversion and populates *conv_spec with an equivalent conversion
157 specification that may later be used by __gconv_open. The charset names
158 might contain options in the form of suffixes that alter the conversion,
159 e.g. "ISO-10646/UTF-8/TRANSLIT". It processes the charset names, ignoring
160 and truncating any suffix options in fromcode, and processing and truncating
161 any suffix options in tocode. Supported suffix options ("TRANSLIT" or
162 "IGNORE") when found in tocode lead to the corresponding flag in *conv_spec
163 to be set to true. Unrecognized suffix options are silently discarded. If
164 the function succeeds, it returns conv_spec back to the caller. It returns
165 NULL upon failure. */
166extern struct gconv_spec *
167__gconv_create_spec (struct gconv_spec *conv_spec, const char *fromcode,
168 const char *tocode);
169libc_hidden_proto (__gconv_create_spec)
170
171/* This function frees all heap memory allocated by __gconv_create_spec. */
172extern void
173__gconv_destroy_spec (struct gconv_spec *conv_spec);
174libc_hidden_proto (__gconv_destroy_spec)
175
176/* Free resources associated with transformation descriptor CD. */
177extern int __gconv_close (__gconv_t cd)
178 attribute_hidden;
179
180/* Transform at most *INBYTESLEFT bytes from buffer starting at *INBUF
181 according to rules described by CD and place up to *OUTBYTESLEFT
182 bytes in buffer starting at *OUTBUF. Return number of non-identical
183 conversions in *IRREVERSIBLE if this pointer is not null. */
184extern int __gconv (__gconv_t cd, const unsigned char **inbuf,
185 const unsigned char *inbufend, unsigned char **outbuf,
186 unsigned char *outbufend, size_t *irreversible)
187 attribute_hidden;
188
189/* Return in *HANDLE a pointer to an array with *NSTEPS elements describing
190 the single steps necessary for transformation from FROMSET to TOSET. */
191extern int __gconv_find_transform (const char *toset, const char *fromset,
192 struct __gconv_step **handle,
193 size_t *nsteps, int flags)
194 attribute_hidden;
195
196/* Search for transformation in cache data. */
197extern int __gconv_lookup_cache (const char *toset, const char *fromset,
198 struct __gconv_step **handle, size_t *nsteps,
199 int flags)
200 attribute_hidden;
201
202/* Compare the two name for whether they are after alias expansion the
203 same. This function uses the cache and fails if none is
204 loaded. */
205extern int __gconv_compare_alias_cache (const char *name1, const char *name2,
206 int *result)
207 attribute_hidden;
208
209/* Free data associated with a step's structure. */
210extern void __gconv_release_step (struct __gconv_step *step)
211 attribute_hidden;
212
213/* Read all the configuration data and cache it if not done so already. */
214extern void __gconv_load_conf (void) attribute_hidden;
215
216/* Try to read module cache file. */
217extern int __gconv_load_cache (void) attribute_hidden;
218
219/* Retrieve pointer to internal cache. */
220extern void *__gconv_get_cache (void);
221
222/* Retrieve pointer to internal module database. */
223extern struct gconv_module *__gconv_get_modules_db (void);
224
225/* Retrieve pointer to internal alias database. */
226extern void *__gconv_get_alias_db (void);
227
228/* Comparison function to search alias. */
229extern int __gconv_alias_compare (const void *p1, const void *p2)
230 attribute_hidden;
231
232/* Clear reference to transformation step implementations which might
233 cause the code to be unloaded. */
234extern int __gconv_close_transform (struct __gconv_step *steps,
235 size_t nsteps)
236 attribute_hidden;
237
238/* Free all resources allocated for the transformation record when
239 using the cache. */
240extern void __gconv_release_cache (struct __gconv_step *steps, size_t nsteps)
241 attribute_hidden;
242
243/* Load shared object named by NAME. If already loaded increment reference
244 count. */
245extern struct __gconv_loaded_object *__gconv_find_shlib (const char *name)
246 attribute_hidden;
247
248/* Release shared object. If no further reference is available unload
249 the object. */
250extern void __gconv_release_shlib (struct __gconv_loaded_object *handle)
251 attribute_hidden;
252
253/* Fill STEP with information about builtin module with NAME. */
254extern void __gconv_get_builtin_trans (const char *name,
255 struct __gconv_step *step)
256 attribute_hidden;
257
258/* Transliteration using the locale's data. */
259extern int __gconv_transliterate (struct __gconv_step *step,
260 struct __gconv_step_data *step_data,
261 const unsigned char *inbufstart,
262 const unsigned char **inbufp,
263 const unsigned char *inbufend,
264 unsigned char **outbufstart,
265 size_t *irreversible);
266libc_hidden_proto (__gconv_transliterate)
267
268/* If NAME is an codeset alias expand it. */
269extern int __gconv_compare_alias (const char *name1, const char *name2)
270 attribute_hidden;
271
272
273/* Builtin transformations. */
274#ifdef _LIBC
275# define __BUILTIN_TRANSFORM(Name) \
276 extern int Name (struct __gconv_step *step, \
277 struct __gconv_step_data *data, \
278 const unsigned char **inbuf, \
279 const unsigned char *inbufend, \
280 unsigned char **outbufstart, size_t *irreversible, \
281 int do_flush, int consume_incomplete)
282
283__BUILTIN_TRANSFORM (__gconv_transform_ascii_internal);
284__BUILTIN_TRANSFORM (__gconv_transform_internal_ascii);
285__BUILTIN_TRANSFORM (__gconv_transform_utf8_internal);
286__BUILTIN_TRANSFORM (__gconv_transform_internal_utf8);
287__BUILTIN_TRANSFORM (__gconv_transform_ucs2_internal);
288__BUILTIN_TRANSFORM (__gconv_transform_internal_ucs2);
289__BUILTIN_TRANSFORM (__gconv_transform_ucs2reverse_internal);
290__BUILTIN_TRANSFORM (__gconv_transform_internal_ucs2reverse);
291__BUILTIN_TRANSFORM (__gconv_transform_internal_ucs4);
292__BUILTIN_TRANSFORM (__gconv_transform_ucs4_internal);
293__BUILTIN_TRANSFORM (__gconv_transform_internal_ucs4le);
294__BUILTIN_TRANSFORM (__gconv_transform_ucs4le_internal);
295__BUILTIN_TRANSFORM (__gconv_transform_internal_utf16);
296__BUILTIN_TRANSFORM (__gconv_transform_utf16_internal);
297# undef __BUITLIN_TRANSFORM
298
299/* Specialized conversion function for a single byte to INTERNAL, recognizing
300 only ASCII characters. */
301extern wint_t __gconv_btwoc_ascii (struct __gconv_step *step, unsigned char c);
302
303#endif
304
305__END_DECLS
306
307#endif /* gconv_int.h */
308