1 /* Handle configuration data.
2 Copyright (C) 1997-2013 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
28 #include <stdio_ext.h>
32 #include <sys/param.h>
34 #include <bits/libc-lock.h>
35 #include <gconv_int.h>
38 /* This is the default path where we look for module lists. */
39 static const char default_gconv_path[] = GCONV_PATH;
41 /* The path elements, as determined by the __gconv_get_path function.
42 All path elements end in a slash. */
43 struct path_elem *__gconv_path_elem;
44 /* Maximum length of a single path element in __gconv_path_elem. */
45 size_t __gconv_max_path_elem_len;
47 /* We use the following struct if we couldn't allocate memory. */
48 static const struct path_elem empty_path_elem = { NULL, 0 };
50 /* Name of the file containing the module information in the directories
52 static const char gconv_conf_filename[] = "gconv-modules";
54 /* Filename extension for the modules. */
56 # define MODULE_EXT ".so"
58 static const char gconv_module_ext[] = MODULE_EXT;
60 /* We have a few builtin transformations. */
61 static struct gconv_module builtin_modules[] =
63 #define BUILTIN_TRANSFORMATION(From, To, Cost, Name, Fct, BtowcFct, \
64 MinF, MaxF, MinT, MaxT) \
66 .from_string = From, \
72 #define BUILTIN_ALIAS(From, To)
74 #include "gconv_builtin.h"
76 #undef BUILTIN_TRANSFORMATION
80 static const char builtin_aliases[] =
82 #define BUILTIN_TRANSFORMATION(From, To, Cost, Name, Fct, BtowcFct, \
83 MinF, MaxF, MinT, MaxT)
84 #define BUILTIN_ALIAS(From, To) From "\0" To "\0"
86 #include "gconv_builtin.h"
88 #undef BUILTIN_TRANSFORMATION
92 #include <libio/libioP.h>
93 #define __getdelim(line, len, c, fp) _IO_getdelim (line, len, c, fp)
96 /* Value of the GCONV_PATH environment variable. */
97 const char *__gconv_path_envvar;
100 /* Test whether there is already a matching module known. */
103 detect_conflict (const char *alias)
105 struct gconv_module *node = __gconv_modules_db;
109 int cmpres = strcmp (alias, node->from_string);
112 /* We have a conflict. */
124 /* The actual code to add aliases. */
126 add_alias2 (const char *from, const char *to, const char *wp, void *modules)
128 /* Test whether this alias conflicts with any available module. */
129 if (detect_conflict (from))
130 /* It does conflict, don't add the alias. */
133 struct gconv_alias *new_alias = (struct gconv_alias *)
134 malloc (sizeof (struct gconv_alias) + (wp - from));
135 if (new_alias != NULL)
139 new_alias->fromname = memcpy ((char *) new_alias
140 + sizeof (struct gconv_alias),
142 new_alias->toname = new_alias->fromname + (to - from);
144 inserted = (void **) __tsearch (new_alias, &__gconv_alias_db,
145 __gconv_alias_compare);
146 if (inserted == NULL || *inserted != new_alias)
147 /* Something went wrong, free this entry. */
155 add_alias (char *rp, void *modules)
157 /* We now expect two more string. The strings are normalized
158 (converted to UPPER case) and strored in the alias database. */
159 char *from, *to, *wp;
161 while (__isspace_l (*rp, _nl_C_locobj_ptr))
164 while (*rp != '\0' && !__isspace_l (*rp, _nl_C_locobj_ptr))
165 *wp++ = __toupper_l (*rp++, _nl_C_locobj_ptr);
167 /* There is no `to' string on the line. Ignore it. */
171 while (__isspace_l (*rp, _nl_C_locobj_ptr))
173 while (*rp != '\0' && !__isspace_l (*rp, _nl_C_locobj_ptr))
174 *wp++ = __toupper_l (*rp++, _nl_C_locobj_ptr);
176 /* No `to' string, ignore the line. */
180 add_alias2 (from, to, wp, modules);
184 /* Insert a data structure for a new module in the search tree. */
187 insert_module (struct gconv_module *newp, int tobefreed)
189 struct gconv_module **rootp = &__gconv_modules_db;
191 while (*rootp != NULL)
193 struct gconv_module *root = *rootp;
196 cmpres = strcmp (newp->from_string, root->from_string);
199 /* Both strings are identical. Insert the string at the
200 end of the `same' list if it is not already there. */
201 while (strcmp (newp->from_string, root->from_string) != 0
202 || strcmp (newp->to_string, root->to_string) != 0)
212 /* This is a no new conversion. But maybe the cost is
214 if (newp->cost_hi < root->cost_hi
215 || (newp->cost_hi == root->cost_hi
216 && newp->cost_lo < root->cost_lo))
218 newp->left = root->left;
219 newp->right = root->right;
220 newp->same = root->same;
235 rootp = &root->right;
238 /* Plug in the new node here. */
243 /* Add new module. */
246 add_module (char *rp, const char *directory, size_t dir_len, void **modules,
247 size_t *nmodules, int modcounter)
252 3. filename of the module
253 4. an optional cost value
255 struct gconv_alias fake_alias;
256 struct gconv_module *new_module;
257 char *from, *to, *module, *wp;
261 while (__isspace_l (*rp, _nl_C_locobj_ptr))
264 while (*rp != '\0' && !__isspace_l (*rp, _nl_C_locobj_ptr))
266 *rp = __toupper_l (*rp, _nl_C_locobj_ptr);
273 while (__isspace_l (*rp, _nl_C_locobj_ptr))
275 while (*rp != '\0' && !__isspace_l (*rp, _nl_C_locobj_ptr))
276 *wp++ = __toupper_l (*rp++, _nl_C_locobj_ptr);
282 while (__isspace_l (*rp, _nl_C_locobj_ptr));
284 while (*rp != '\0' && !__isspace_l (*rp, _nl_C_locobj_ptr))
288 /* There is no cost, use one by default. */
294 /* There might be a cost value. */
298 cost_hi = strtol (rp, &endp, 10);
299 if (rp == endp || cost_hi < 1)
300 /* No useful information. */
304 if (module[0] == '\0')
305 /* No module name given. */
307 if (module[0] == '/')
310 /* See whether we must add the ending. */
312 if (wp - module < (ptrdiff_t) sizeof (gconv_module_ext)
313 || memcmp (wp - sizeof (gconv_module_ext), gconv_module_ext,
314 sizeof (gconv_module_ext)) != 0)
315 /* We must add the module extension. */
316 need_ext = sizeof (gconv_module_ext) - 1;
318 /* See whether we have already an alias with this name defined. */
319 fake_alias.fromname = strndupa (from, to - from);
321 if (__tfind (&fake_alias, &__gconv_alias_db, __gconv_alias_compare) != NULL)
322 /* This module duplicates an alias. */
325 new_module = (struct gconv_module *) calloc (1,
326 sizeof (struct gconv_module)
328 + dir_len + need_ext);
329 if (new_module != NULL)
333 new_module->from_string = tmp = (char *) (new_module + 1);
334 tmp = __mempcpy (tmp, from, to - from);
336 new_module->to_string = tmp;
337 tmp = __mempcpy (tmp, to, module - to);
339 new_module->cost_hi = cost_hi;
340 new_module->cost_lo = modcounter;
342 new_module->module_name = tmp;
345 tmp = __mempcpy (tmp, directory, dir_len);
347 tmp = __mempcpy (tmp, module, wp - module);
350 memcpy (tmp - 1, gconv_module_ext, sizeof (gconv_module_ext));
352 /* Now insert the new module data structure in our search tree. */
353 insert_module (new_module, 1);
358 /* Read the next configuration file. */
361 read_conf_file (const char *filename, const char *directory, size_t dir_len,
362 void **modules, size_t *nmodules)
364 /* Note the file is opened with cancellation in the I/O functions
366 FILE *fp = fopen (filename, "rce");
369 static int modcounter;
371 /* Don't complain if a file is not present or readable, simply silently
376 /* No threads reading from this stream. */
377 __fsetlocking (fp, FSETLOCKING_BYCALLER);
379 /* Process the known entries of the file. Comments start with `#' and
380 end with the end of the line. Empty lines are ignored. */
381 while (!feof_unlocked (fp))
383 char *rp, *endp, *word;
384 ssize_t n = __getdelim (&line, &line_len, '\n', fp);
386 /* An error occurred. */
390 /* Terminate the line (excluding comments or newline) by an NUL byte
391 to simplify the following code. */
392 endp = strchr (rp, '#');
396 if (rp[n - 1] == '\n')
399 while (__isspace_l (*rp, _nl_C_locobj_ptr))
402 /* If this is an empty line go on with the next one. */
407 while (*rp != '\0' && !__isspace_l (*rp, _nl_C_locobj_ptr))
410 if (rp - word == sizeof ("alias") - 1
411 && memcmp (word, "alias", sizeof ("alias") - 1) == 0)
412 add_alias (rp, *modules);
413 else if (rp - word == sizeof ("module") - 1
414 && memcmp (word, "module", sizeof ("module") - 1) == 0)
415 add_module (rp, directory, dir_len, modules, nmodules, modcounter++);
417 /* Otherwise ignore the line. */
426 /* Determine the directories we are looking for data in. */
429 __gconv_get_path (void)
431 struct path_elem *result;
432 __libc_lock_define_initialized (static, lock);
434 __libc_lock_lock (lock);
436 /* Make sure there wasn't a second thread doing it already. */
437 result = (struct path_elem *) __gconv_path_elem;
440 /* Determine the complete path first. */
442 size_t gconv_path_len;
450 if (__gconv_path_envvar == NULL)
452 /* No user-defined path. Make a modifiable copy of the
454 gconv_path = strdupa (default_gconv_path);
455 gconv_path_len = sizeof (default_gconv_path);
461 /* Append the default path to the user-defined path. */
462 size_t user_len = strlen (__gconv_path_envvar);
464 gconv_path_len = user_len + 1 + sizeof (default_gconv_path);
465 gconv_path = alloca (gconv_path_len);
466 __mempcpy (__mempcpy (__mempcpy (gconv_path, __gconv_path_envvar,
469 default_gconv_path, sizeof (default_gconv_path));
470 cwd = __getcwd (NULL, 0);
471 cwdlen = strlen (cwd);
473 assert (default_gconv_path[0] == '/');
475 /* In a first pass we calculate the number of elements. */
477 cp = strchr (gconv_path, ':');
484 cp = strchr (cp + 1, ':');
487 /* Allocate the memory for the result. */
488 result = (struct path_elem *) malloc ((nelems + 1)
489 * sizeof (struct path_elem)
490 + gconv_path_len + nelems
491 + (nelems - 1) * (cwdlen + 1));
494 char *strspace = (char *) &result[nelems + 1];
497 /* Separate the individual parts. */
498 __gconv_max_path_elem_len = 0;
499 elem = __strtok_r (gconv_path, ":", &gconv_path);
500 assert (elem != NULL);
503 result[n].name = strspace;
506 assert (cwd != NULL);
507 strspace = __mempcpy (strspace, cwd, cwdlen);
510 strspace = __stpcpy (strspace, elem);
511 if (strspace[-1] != '/')
514 result[n].len = strspace - result[n].name;
515 if (result[n].len > __gconv_max_path_elem_len)
516 __gconv_max_path_elem_len = result[n].len;
521 while ((elem = __strtok_r (NULL, ":", &gconv_path)) != NULL);
523 result[n].name = NULL;
527 __gconv_path_elem = result ?: (struct path_elem *) &empty_path_elem;
532 __libc_lock_unlock (lock);
536 /* Read all configuration files found in the user-specified and the default
540 __gconv_read_conf (void)
542 void *modules = NULL;
544 int save_errno = errno;
547 /* First see whether we should use the cache. */
548 if (__gconv_load_cache () == 0)
550 /* Yes, we are done. */
551 __set_errno (save_errno);
556 /* Find out where we have to look. */
557 if (__gconv_path_elem == NULL)
560 for (cnt = 0; __gconv_path_elem[cnt].name != NULL; ++cnt)
562 const char *elem = __gconv_path_elem[cnt].name;
563 size_t elem_len = __gconv_path_elem[cnt].len;
566 /* No slash needs to be inserted between elem and gconv_conf_filename;
567 elem already ends in a slash. */
568 filename = alloca (elem_len + sizeof (gconv_conf_filename));
569 __mempcpy (__mempcpy (filename, elem, elem_len),
570 gconv_conf_filename, sizeof (gconv_conf_filename));
572 /* Read the next configuration file. */
573 read_conf_file (filename, elem, elem_len, &modules, &nmodules);
577 /* Add the internal modules. */
578 for (cnt = 0; cnt < sizeof (builtin_modules) / sizeof (builtin_modules[0]);
581 struct gconv_alias fake_alias;
583 fake_alias.fromname = (char *) builtin_modules[cnt].from_string;
585 if (__tfind (&fake_alias, &__gconv_alias_db, __gconv_alias_compare)
587 /* It'll conflict so don't add it. */
590 insert_module (&builtin_modules[cnt], 0);
593 /* Add aliases for builtin conversions. */
594 const char *cp = builtin_aliases;
597 const char *from = cp;
598 const char *to = __rawmemchr (from, '\0') + 1;
599 cp = __rawmemchr (to, '\0') + 1;
601 add_alias2 (from, to, cp, modules);
605 /* Restore the error number. */
606 __set_errno (save_errno);
611 /* Free all resources if necessary. */
612 libc_freeres_fn (free_mem)
614 if (__gconv_path_elem != NULL && __gconv_path_elem != &empty_path_elem)
615 free ((void *) __gconv_path_elem);