1 /* Handle configuration data.
2 Copyright (C) 1997-2015 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 <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
= __glibc_unlikely (cwd
== NULL
) ? 0 : 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
);