glibc/iconv/gconv_conf.c

467 lines
12 KiB
C

/* Handle configuration data.
Copyright (C) 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <search.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/param.h>
#include <gconv_int.h>
/* This is the default path where we look for module lists. */
static const char default_gconv_path[] = GCONV_PATH;
/* Name of the file containing the module information in the directories
along the path. */
static const char gconv_conf_filename[] = "gconv-modules";
/* Filename extension for the modules. */
#ifndef MODULE_EXT
# define MODULE_EXT ".so"
#endif
static const char gconv_module_ext[] = MODULE_EXT;
/* We have a few builtin transformations. */
static struct gconv_module builtin_modules[] =
{
#define BUILTIN_TRANSFORMATION(From, ConstPfx, ConstLen, To, Cost, Name, \
Fct, Init, End, MinF, MaxF, MinT, MaxT) \
{ \
from_pattern: From, \
from_constpfx: ConstPfx, \
from_constpfx_len: ConstLen, \
from_regex: NULL, \
to_string: To, \
cost_hi: Cost, \
cost_lo: INT_MAX, \
module_name: Name \
},
#define BUILTIN_ALIAS(From, To)
#include "gconv_builtin.h"
};
#undef BUILTIN_TRANSFORMATION
#undef BUILTIN_ALIAS
static const char *
builtin_aliases[] =
{
#define BUILTIN_TRANSFORMATION(From, ConstPfx, ConstLen, To, Cost, Name, \
Fct, Init, End, MinF, MaxF, MinT, MaxT)
#define BUILTIN_ALIAS(From, To) From " " To,
#include "gconv_builtin.h"
};
/* Function for searching module. */
static int
module_compare (const void *p1, const void *p2)
{
struct gconv_module *s1 = (struct gconv_module *) p1;
struct gconv_module *s2 = (struct gconv_module *) p2;
int result;
if (s1->from_pattern == NULL)
{
if (s2->from_pattern == NULL)
result = strcmp (s1->from_constpfx, s2->from_constpfx);
else
result = -1;
}
else if (s2->from_pattern == NULL)
result = 1;
else
result = strcmp (s1->from_pattern, s2->from_pattern);
if (result == 0)
result = strcmp (s1->to_string, s2->to_string);
return result;
}
/* Add new alias. */
static inline void
add_alias (char *rp)
{
/* We now expect two more string. The strings are normalized
(converted to UPPER case) and strored in the alias database. */
struct gconv_alias *new_alias;
char *from, *to, *wp;
while (isspace (*rp))
++rp;
from = wp = rp;
while (*rp != '\0' && !isspace (*rp))
++rp;
if (*rp == '\0')
/* There is no `to' string on the line. Ignore it. */
return;
*rp++ = '\0';
to = wp = rp;
while (isspace (*rp))
++rp;
while (*rp != '\0' && !isspace (*rp))
*wp++ = *rp++;
if (to == wp)
/* No `to' string, ignore the line. */
return;
*wp++ = '\0';
new_alias = (struct gconv_alias *)
malloc (sizeof (struct gconv_alias) + (wp - from));
if (new_alias != NULL)
{
new_alias->fromname = memcpy ((char *) new_alias
+ sizeof (struct gconv_alias),
from, wp - from);
new_alias->toname = new_alias->fromname + (to - from);
if (__tsearch (new_alias, &__gconv_alias_db, __gconv_alias_compare)
== NULL)
/* Something went wrong, free this entry. */
free (new_alias);
}
}
/* Add new module. */
static inline void
add_module (char *rp, const char *directory, size_t dir_len, void **modules,
size_t *nmodules, int modcounter)
{
/* We expect now
1. `from' name
2. `to' name
3. filename of the module
4. an optional cost value
*/
struct gconv_module *new_module;
char *from, *to, *module, *wp;
size_t const_len;
int from_is_regex;
int need_ext;
int cost_hi;
while (isspace (*rp))
++rp;
from = rp;
from_is_regex = 0;
while (*rp != '\0' && !isspace (*rp))
{
if (!isalnum (*rp) && *rp != '-' && *rp != '/' && *rp != '.'
&& *rp != '_')
from_is_regex = 1;
++rp;
}
if (*rp == '\0')
return;
*rp++ = '\0';
to = wp = rp;
while (isspace (*rp))
++rp;
while (*rp != '\0' && !isspace (*rp))
*wp++ = *rp++;
if (*rp == '\0')
return;
*wp++ = '\0';
do
++rp;
while (isspace (*rp));
module = wp;
while (*rp != '\0' && !isspace (*rp))
*wp++ = *rp++;
if (*rp == '\0')
{
/* There is no cost, use one by default. */
*wp++ = '\0';
cost_hi = 1;
}
else
{
/* There might be a cost value. */
char *endp;
*wp++ = '\0';
cost_hi = strtol (rp, &endp, 10);
if (rp == endp)
/* No useful information. */
cost_hi = 1;
}
if (module[0] == '\0')
/* No module name given. */
return;
if (module[0] == '/')
dir_len = 0;
else
/* Increment by one for the slash. */
++dir_len;
/* See whether we must add the ending. */
need_ext = 0;
if (wp - module < sizeof (gconv_module_ext)
|| memcmp (wp - sizeof (gconv_module_ext), gconv_module_ext,
sizeof (gconv_module_ext)) != 0)
/* We must add the module extension. */
need_ext = sizeof (gconv_module_ext) - 1;
/* We've collected all the information, now create an entry. */
if (from_is_regex)
{
const_len = 0;
while (isalnum (from[const_len]) || from[const_len] == '-'
|| from[const_len] == '/' || from[const_len] == '.'
|| from[const_len] == '_')
++const_len;
}
else
const_len = to - from - 1;
new_module = (struct gconv_module *) malloc (sizeof (struct gconv_module)
+ (wp - from)
+ dir_len + need_ext);
if (new_module != NULL)
{
char *tmp;
new_module->from_constpfx = memcpy ((char *) new_module
+ sizeof (struct gconv_module),
from, to - from);
if (from_is_regex)
new_module->from_pattern = new_module->from_constpfx;
else
new_module->from_pattern = NULL;
new_module->from_constpfx_len = const_len;
new_module->from_regex = NULL;
new_module->to_string = memcpy ((char *) new_module->from_constpfx
+ (to - from), to, module - to);
new_module->cost_hi = cost_hi;
new_module->cost_lo = modcounter;
new_module->module_name = (char *) new_module->to_string + (module - to);
if (dir_len == 0)
tmp = (char *) new_module->module_name;
else
{
tmp = __mempcpy ((char *) new_module->module_name,
directory, dir_len - 1);
*tmp++ = '/';
}
tmp = __mempcpy (tmp, module, wp - module);
if (need_ext)
memcpy (tmp - 1, gconv_module_ext, sizeof (gconv_module_ext));
if (__tfind (new_module, modules, module_compare) == NULL)
if (__tsearch (new_module, modules, module_compare) == NULL)
/* Something went wrong while inserting the new module. */
free (new_module);
else
++*nmodules;
}
}
static void
insert_module (const void *nodep, VISIT value, int level)
{
if (value == preorder || value == leaf)
__gconv_modules_db[__gconv_nmodules++] = *(struct gconv_module **) nodep;
}
static void
nothing (void *unused __attribute__ ((unused)))
{
}
/* Read the next configuration file. */
static void
internal_function
read_conf_file (const char *filename, const char *directory, size_t dir_len,
void **modules, size_t *nmodules)
{
FILE *fp = fopen (filename, "r");
char *line = NULL;
size_t line_len = 0;
int modcounter = 0;
/* Don't complain if a file is not present or readable, simply silently
ignore it. */
if (fp == NULL)
return;
/* Process the known entries of the file. Comments start with `#' and
end with the end of the line. Empty lines are ignored. */
while (!feof (fp))
{
char *rp, *endp, *word;
ssize_t n = __getdelim (&line, &line_len, '\n', fp);
if (n < 0)
/* An error occurred. */
break;
rp = line;
/* Terminate the line (excluding comments or newline) by an NUL byte
to simplify the following code. */
endp = strchr (rp, '#');
if (endp != NULL)
*endp = '\0';
else
if (rp[n - 1] == '\n')
rp[n - 1] = '\0';
while (isspace (*rp))
++rp;
/* If this is an empty line go on with the next one. */
if (rp == endp)
continue;
word = rp;
while (*rp != '\0' && !isspace (*rp))
++rp;
if (rp - word == sizeof ("alias") - 1
&& memcmp (word, "alias", sizeof ("alias") - 1) == 0)
add_alias (rp);
else if (rp - word == sizeof ("module") - 1
&& memcmp (word, "module", sizeof ("module") - 1) == 0)
add_module (rp, directory, dir_len, modules, nmodules, modcounter++);
/* else */
/* Otherwise ignore the line. */
}
if (line != NULL)
free (line);
fclose (fp);
}
/* Read all configuration files found in the user-specified and the default
path. */
void
internal_function
__gconv_read_conf (void)
{
const char *user_path = __secure_getenv ("GCONV_PATH");
char *gconv_path, *elem;
void *modules = NULL;
size_t nmodules = 0;
int save_errno = errno;
size_t cnt;
if (user_path == NULL)
/* No user-defined path. Make a modifiable copy of the default path. */
gconv_path = strdupa (default_gconv_path);
else
{
/* Append the default path to the user-defined path. */
size_t user_len = strlen (user_path);
char *tmp;
gconv_path = alloca (user_len + 1 + sizeof (default_gconv_path));
tmp = __mempcpy (gconv_path, user_path, user_len);
*tmp++ = ':';
__mempcpy (tmp, default_gconv_path, sizeof (default_gconv_path));
}
elem = strtok_r (gconv_path, ":", &gconv_path);
while (elem != NULL)
{
#ifndef MAXPATHLEN
/* We define a reasonable limit. */
# define MAXPATHLEN 4096
#endif
char real_elem[MAXPATHLEN];
if (__realpath (elem, real_elem) != NULL)
{
size_t elem_len = strlen (real_elem);
char *filename, *tmp;
filename = alloca (elem_len + 1 + sizeof (gconv_conf_filename));
tmp = __mempcpy (filename, real_elem, elem_len);
*tmp++ = '/';
__mempcpy (tmp, gconv_conf_filename, sizeof (gconv_conf_filename));
/* Read the next configuration file. */
read_conf_file (filename, real_elem, elem_len, &modules, &nmodules);
}
/* Get next element in the path. */
elem = strtok_r (NULL, ":", &gconv_path);
}
/* If the configuration files do not contain any valid module specification
remember this by setting the pointer to the module array to NULL. */
nmodules += sizeof (builtin_modules) / sizeof (builtin_modules[0]);
if (nmodules == 0)
__gconv_modules_db = NULL;
else
{
__gconv_modules_db =
(struct gconv_module **) malloc (nmodules
* sizeof (struct gconv_module));
if (__gconv_modules_db != NULL)
{
size_t cnt;
/* Insert all module entries into the array. */
__twalk (modules, insert_module);
/* No remove the tree data structure. */
__tdestroy (modules, nothing);
/* Finally insert the builtin transformations. */
for (cnt = 0; cnt < (sizeof (builtin_modules)
/ sizeof (struct gconv_module)); ++cnt)
__gconv_modules_db[__gconv_nmodules++] = &builtin_modules[cnt];
}
}
/* Add aliases for builtin conversions. */
cnt = sizeof (builtin_aliases) / sizeof (builtin_aliases[0]);
while (cnt > 0)
{
char *copy = strdupa (builtin_aliases[--cnt]);
add_alias (copy);
}
/* Restore the error number. */
__set_errno (save_errno);
}