iconv/gconv_int.h

   1 /* Copyright (C) 1997-2020 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.  */
  32 struct 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.  */
  42 struct __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.  */
  62 struct 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.  */
  79 struct gconv_spec
  80 {
  81   char *fromcode;
  82   char *tocode;
  83   bool translit;
  84   bool ignore;
  85 };
  86
  87 /* Flags for `gconv_open'.  */
  88 enum
  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.  */
  95 enum
  96 {
  97   __GCONV_NULCONV = -1
  98 };
  99
 100 /* Global variables.  */
 101
 102 /* Database of alias names.  */
 103 extern void *__gconv_alias_db attribute_hidden;
 104
 105 /* Array with available modules.  */
 106 extern struct gconv_module *__gconv_modules_db attribute_hidden;
 107
 108 /* Value of the GCONV_PATH environment variable.  */
 109 extern 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.  */
 151 extern int __gconv_open (struct gconv_spec *conv_spec,
 152                          __gconv_t *handle, int flags);
 153 libc_hidden_proto (__gconv_open)
 154
 155 /* Free resources associated with transformation descriptor CD.  */
 156 extern int __gconv_close (__gconv_t cd)
 157      attribute_hidden;
 158
 159 /* Transform at most *INBYTESLEFT bytes from buffer starting at *INBUF
 160    according to rules described by CD and place up to *OUTBYTESLEFT
 161    bytes in buffer starting at *OUTBUF.  Return number of non-identical
 162    conversions in *IRREVERSIBLE if this pointer is not null.  */
 163 extern int __gconv (__gconv_t cd, const unsigned char **inbuf,
 164                     const unsigned char *inbufend, unsigned char **outbuf,
 165                     unsigned char *outbufend, size_t *irreversible)
 166      attribute_hidden;
 167
 168 /* Return in *HANDLE a pointer to an array with *NSTEPS elements describing
 169    the single steps necessary for transformation from FROMSET to TOSET.  */
 170 extern int __gconv_find_transform (const char *toset, const char *fromset,
 171                                    struct __gconv_step **handle,
 172                                    size_t *nsteps, int flags)
 173      attribute_hidden;
 174
 175 /* Search for transformation in cache data.  */
 176 extern int __gconv_lookup_cache (const char *toset, const char *fromset,
 177                                  struct __gconv_step **handle, size_t *nsteps,
 178                                  int flags)
 179      attribute_hidden;
 180
 181 /* Compare the two name for whether they are after alias expansion the
 182    same.  This function uses the cache and fails if none is
 183    loaded.  */
 184 extern int __gconv_compare_alias_cache (const char *name1, const char *name2,
 185                                         int *result)
 186      attribute_hidden;
 187
 188 /* Free data associated with a step's structure.  */
 189 extern void __gconv_release_step (struct __gconv_step *step)
 190      attribute_hidden;
 191
 192 /* Read all the configuration data and cache it if not done so already.  */
 193 extern void __gconv_load_conf (void) attribute_hidden;
 194
 195 /* Try to read module cache file.  */
 196 extern int __gconv_load_cache (void) attribute_hidden;
 197
 198 /* Retrieve pointer to internal cache.  */
 199 extern void *__gconv_get_cache (void);
 200
 201 /* Retrieve pointer to internal module database.  */
 202 extern struct gconv_module *__gconv_get_modules_db (void);
 203
 204 /* Retrieve pointer to internal alias database.  */
 205 extern void *__gconv_get_alias_db (void);
 206
 207 /* Comparison function to search alias.  */
 208 extern int __gconv_alias_compare (const void *p1, const void *p2)
 209      attribute_hidden;
 210
 211 /* Clear reference to transformation step implementations which might
 212    cause the code to be unloaded.  */
 213 extern int __gconv_close_transform (struct __gconv_step *steps,
 214                                     size_t nsteps)
 215      attribute_hidden;
 216
 217 /* Free all resources allocated for the transformation record when
 218    using the cache.  */
 219 extern void __gconv_release_cache (struct __gconv_step *steps, size_t nsteps)
 220      attribute_hidden;
 221
 222 /* Load shared object named by NAME.  If already loaded increment reference
 223    count.  */
 224 extern struct __gconv_loaded_object *__gconv_find_shlib (const char *name)
 225      attribute_hidden;
 226
 227 /* Release shared object.  If no further reference is available unload
 228    the object.  */
 229 extern void __gconv_release_shlib (struct __gconv_loaded_object *handle)
 230      attribute_hidden;
 231
 232 /* Fill STEP with information about builtin module with NAME.  */
 233 extern void __gconv_get_builtin_trans (const char *name,
 234                                        struct __gconv_step *step)
 235      attribute_hidden;
 236
 237 /* Transliteration using the locale's data.  */
 238 extern int __gconv_transliterate (struct __gconv_step *step,
 239                                   struct __gconv_step_data *step_data,
 240                                   const unsigned char *inbufstart,
 241                                   const unsigned char **inbufp,
 242                                   const unsigned char *inbufend,
 243                                   unsigned char **outbufstart,
 244                                   size_t *irreversible);
 245 libc_hidden_proto (__gconv_transliterate)
 246
 247 /* If NAME is an codeset alias expand it.  */
 248 extern int __gconv_compare_alias (const char *name1, const char *name2)
 249      attribute_hidden;
 250
 251
 252 /* Builtin transformations.  */
 253 #ifdef _LIBC
 254 # define __BUILTIN_TRANSFORM(Name) \
 255   extern int Name (struct __gconv_step *step,                                 \
 256                    struct __gconv_step_data *data,                            \
 257                    const unsigned char **inbuf,                               \
 258                    const unsigned char *inbufend,                             \
 259                    unsigned char **outbufstart, size_t *irreversible,         \
 260                    int do_flush, int consume_incomplete)
 261
 262 __BUILTIN_TRANSFORM (__gconv_transform_ascii_internal);
 263 __BUILTIN_TRANSFORM (__gconv_transform_internal_ascii);
 264 __BUILTIN_TRANSFORM (__gconv_transform_utf8_internal);
 265 __BUILTIN_TRANSFORM (__gconv_transform_internal_utf8);
 266 __BUILTIN_TRANSFORM (__gconv_transform_ucs2_internal);
 267 __BUILTIN_TRANSFORM (__gconv_transform_internal_ucs2);
 268 __BUILTIN_TRANSFORM (__gconv_transform_ucs2reverse_internal);
 269 __BUILTIN_TRANSFORM (__gconv_transform_internal_ucs2reverse);
 270 __BUILTIN_TRANSFORM (__gconv_transform_internal_ucs4);
 271 __BUILTIN_TRANSFORM (__gconv_transform_ucs4_internal);
 272 __BUILTIN_TRANSFORM (__gconv_transform_internal_ucs4le);
 273 __BUILTIN_TRANSFORM (__gconv_transform_ucs4le_internal);
 274 __BUILTIN_TRANSFORM (__gconv_transform_internal_utf16);
 275 __BUILTIN_TRANSFORM (__gconv_transform_utf16_internal);
 276 # undef __BUITLIN_TRANSFORM
 277
 278 /* Specialized conversion function for a single byte to INTERNAL, recognizing
 279    only ASCII characters.  */
 280 extern wint_t __gconv_btwoc_ascii (struct __gconv_step *step, unsigned char c);
 281
 282 #endif
 283
 284 __END_DECLS
 285
 286 #endif /* gconv_int.h */