/* localealias.c -- handle aliases for locale names
Copyright (C) 1995, 1996 Free Software Foundation, Inc.
This file is part of the GNU C Library. Its master source is NOT part of
the C library, however. The master source lives in /gd/gnu/lib.
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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <ctype.h>
#include <stdio.h>
#include <sys/types.h>
#ifdef __GNUC__
# define alloca __builtin_alloca
# define HAVE_ALLOCA 1
#else
# if defined HAVE_ALLOCA_H || defined _LIBC
# include <alloca.h>
# else
# ifdef _AIX
#pragma alloca
# else
# ifndef alloca
char *alloca ();
# endif
# endif
# endif
#endif
#if defined STDC_HEADERS || defined _LIBC
# include <stdlib.h>
#else
char *getenv ();
# ifdef HAVE_MALLOC_H
# include <malloc.h>
# else
void free ();
# endif
#endif
#if defined HAVE_STRING_H || defined _LIBC
# ifndef _GNU_SOURCE
# define _GNU_SOURCE 1
# endif
# include <string.h>
#else
# include <strings.h>
#endif
#if !HAVE_STRCHR && !defined _LIBC
# ifndef strchr
# define strchr index
# endif
#endif
#include "gettext.h"
#include "gettextP.h"
/* @@ end of prolog @@ */
#ifdef _LIBC
/* Rename the non ANSI C functions. This is required by the standard
because some ANSI C functions will require linking with this object
file and the name space must not be polluted. */
# define strcasecmp __strcasecmp
#endif
/* For those loosing systems which don't have `alloca' we have to add
some additional code emulating it. */
#ifdef HAVE_ALLOCA
/* Nothing has to be done. */
# define ADD_BLOCK(list, address) /* nothing */
# define FREE_BLOCKS(list) /* nothing */
#else
struct block_list
{
void *address;
struct block_list *next;
};
# define ADD_BLOCK(list, addr) \
do { \
struct block_list *newp = (struct block_list *) malloc (sizeof (*newp)); \
/* If we cannot get a free block we cannot add the new element to \
the list. */ \
if (newp != NULL) { \
newp->address = (addr); \
newp->next = (list); \
(list) = newp; \
} \
} while (0)
# define FREE_BLOCKS(list) \
do { \
while (list != NULL) { \
struct block_list *old = list; \
list = list->next; \
free (old); \
} \
} while (0)
# undef alloca
# define alloca(size) (malloc (size))
#endif /* have alloca */
struct alias_map
{
const char *alias;
const char *value;
};
static struct alias_map *map;
static size_t nmap = 0;
static size_t maxmap = 0;
/* Prototypes for local functions. */
static size_t read_alias_file PARAMS ((const char *fname, int fname_len));
static void extend_alias_table PARAMS ((void));
static int alias_compare PARAMS ((const struct alias_map *map1,
const struct alias_map *map2));
const char *
_nl_expand_alias (name)
const char *name;
{
static const char *locale_alias_path = LOCALE_ALIAS_PATH;
struct alias_map *retval;
size_t added;
do
{
struct alias_map item;
item.alias = name;
if (nmap > 0)
retval = (struct alias_map *) bsearch (&item, map, nmap,
sizeof (struct alias_map),
(int (*) PARAMS ((const void *,
const void *))
) alias_compare);
else
retval = NULL;
/* We really found an alias. Return the value. */
if (retval != NULL)
return retval->value;
/* Perhaps we can find another alias file. */
added = 0;
while (added == 0 && locale_alias_path[0] != '\0')
{
const char *start;
while (locale_alias_path[0] == ':')
++locale_alias_path;
start = locale_alias_path;
while (locale_alias_path[0] != '\0' && locale_alias_path[0] != ':')
++locale_alias_path;
if (start < locale_alias_path)
added = read_alias_file (start, locale_alias_path - start);
}
}
while (added != 0);
return NULL;
}
static size_t
read_alias_file (fname, fname_len)
const char *fname;
int fname_len;
{
#ifndef HAVE_ALLOCA
struct block_list *block_list = NULL;
#endif
FILE *fp;
char *full_fname;
size_t added;
static const char aliasfile[] = "/locale.alias";
full_fname = (char *) alloca (fname_len + sizeof aliasfile);
ADD_BLOCK (block_list, full_fname);
memcpy (full_fname, fname, fname_len);
memcpy (&full_fname[fname_len], aliasfile, sizeof aliasfile);
fp = fopen (full_fname, "r");
if (fp == NULL)
{
FREE_BLOCKS (block_list);
return 0;
}
added = 0;
while (!feof (fp))
{
/* It is a reasonable approach to use a fix buffer here because
a) we are only interested in the first two fields
b) these fields must be usable as file names and so must not
be that long
*/
char buf[BUFSIZ];
char *alias;
char *value;
char *cp;
if (fgets (buf, BUFSIZ, fp) == NULL)
/* EOF reached. */
break;
cp = buf;
/* Ignore leading white space. */
while (isspace (cp[0]))
++cp;
/* A leading '#' signals a comment line. */
if (cp[0] != '\0' && cp[0] != '#')
{
alias = cp++;
while (cp[0] != '\0' && !isspace (cp[0]))
++cp;
/* Terminate alias name. */
if (cp[0] != '\0')
*cp++ = '\0';
/* Now look for the beginning of the value. */
while (isspace (cp[0]))
++cp;
if (cp[0] != '\0')
{
char *tp;
size_t len;
value = cp++;
while (cp[0] != '\0' && !isspace (cp[0]))
++cp;
/* Terminate value. */
if (cp[0] == '\n')
{
/* This has to be done to make the following test
for the end of line possible. We are looking for
the terminating '\n' which do not overwrite here. */
*cp++ = '\0';
*cp = '\n';
}
else if (cp[0] != '\0')
*cp++ = '\0';
if (nmap >= maxmap)
extend_alias_table ();
/* We cannot depend on strdup available in the libc. Sigh! */
len = strlen (alias) + 1;
tp = (char *) malloc (len);
if (tp == NULL)
{
FREE_BLOCKS (block_list);
return added;
}
memcpy (tp, alias, len);
map[nmap].alias = tp;
len = strlen (value) + 1;
tp = (char *) malloc (len);
if (tp == NULL)
{
FREE_BLOCKS (block_list);
return added;
}
memcpy (tp, value, len);
map[nmap].value = tp;
++nmap;
++added;
}
}
/* Possibily not the whole line fitted into the buffer. Ignore
the rest of the line. */
while (strchr (cp, '\n') == NULL)
{
cp = buf;
if (fgets (buf, BUFSIZ, fp) == NULL)
/* Make sure the inner loop will be left. The outer loop
will exit at the `feof' test. */
*cp = '\n';
}
}
/* Should we test for ferror()? I think we have to silently ignore
errors. --drepper */
fclose (fp);
if (added > 0)
qsort (map, nmap, sizeof (struct alias_map),
(int (*) PARAMS ((const void *, const void *))) alias_compare);
FREE_BLOCKS (block_list);
return added;
}
static void
extend_alias_table ()
{
size_t new_size;
struct alias_map *new_map;
new_size = maxmap == 0 ? 100 : 2 * maxmap;
new_map = (struct alias_map *) malloc (new_size
* sizeof (struct alias_map));
if (new_map == NULL)
/* Simply don't extend: we don't have any more core. */
return;
memcpy (new_map, map, nmap * sizeof (struct alias_map));
if (maxmap != 0)
free (map);
map = new_map;
maxmap = new_size;
}
static int
alias_compare (map1, map2)
const struct alias_map *map1;
const struct alias_map *map2;
{
#if defined _LIBC || defined HAVE_STRCASECMP
return strcasecmp (map1->alias, map2->alias);
#else
const unsigned char *p1 = (const unsigned char *) map1->alias;
const unsigned char *p2 = (const unsigned char *) map2->alias;
unsigned char c1, c2;
if (p1 == p2)
return 0;
do
{
/* I know this seems to be odd but the tolower() function in
some systems libc cannot handle nonalpha characters. */
c1 = isupper (*p1) ? tolower (*p1) : *p1;
c2 = isupper (*p2) ? tolower (*p2) : *p2;
if (c1 == '\0')
break;
++p1;
++p2;
}
while (c1 == c2);
return c1 - c2;
#endif
}