Initial revision

From-SVN: r19498

gcc/intl/localealias.c

+/* Handle aliases for locale names.
+   Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
+   Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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>
+# ifndef memcpy
+#  define memcpy(Dst, Src, Num) bcopy (Src, Dst, Num)
+# endif
+#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
+
+# define mempcpy __mempcpy
+# define HAVE_MEMPCPY	1
+
+/* We need locking here since we can be called from different places.  */
+# include <bits/libc-lock.h>
+
+__libc_lock_define_initialized (static, lock);
+#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 char *string_space = NULL;
+static size_t string_space_act = 0;
+static size_t string_space_max = 0;
+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))
+     internal_function;
+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;
+  const char *result = NULL;
+  size_t added;
+
+#ifdef _LIBC
+  __libc_lock_lock (lock);
+#endif
+
+  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)
+	{
+	  result = retval->value;
+	  break;
+	}
+
+      /* 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);
+
+#ifdef _LIBC
+  __libc_lock_unlock (lock);
+#endif
+
+  return result;
+}
+
+
+static size_t
+internal_function
+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);
+#ifdef HAVE_MEMPCPY
+  mempcpy (mempcpy (full_fname, fname, fname_len),
+	   aliasfile, sizeof aliasfile);
+#else
+  memcpy (full_fname, fname, fname_len);
+  memcpy (&full_fname[fname_len], aliasfile, sizeof aliasfile);
+#endif
+
+  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
+       */
+      unsigned char buf[BUFSIZ];
+      unsigned char *alias;
+      unsigned char *value;
+      unsigned char *cp;
+
+      if (fgets (buf, sizeof buf, fp) == NULL)
+	/* EOF reached.  */
+	break;
+
+      /* Possibly not the whole line fits into the buffer.  Ignore
+	 the rest of the line.  */
+      if (strchr (buf, '\n') == NULL)
+	{
+	  char altbuf[BUFSIZ];
+	  do
+	    if (fgets (altbuf, sizeof altbuf, fp) == NULL)
+	      /* Make sure the inner loop will be left.  The outer loop
+		 will exit at the `feof' test.  */
+	      break;
+	  while (strchr (altbuf, '\n') == NULL);
+	}
+
+      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')
+	    {
+	      size_t alias_len;
+	      size_t value_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 ();
+
+	      alias_len = strlen (alias) + 1;
+	      value_len = strlen (value) + 1;
+
+	      if (string_space_act + alias_len + value_len > string_space_max)
+		{
+		  /* Increase size of memory pool.  */
+		  size_t new_size = (string_space_max
+				     + (alias_len + value_len > 1024
+					? alias_len + value_len : 1024));
+		  char *new_pool = (char *) realloc (string_space, new_size);
+		  if (new_pool == NULL)
+		    {
+		      FREE_BLOCKS (block_list);
+		      return added;
+		    }
+		  string_space = new_pool;
+		  string_space_max = new_size;
+		}
+
+	      map[nmap].alias = memcpy (&string_space[string_space_act],
+					alias, alias_len);
+	      string_space_act += alias_len;
+
+	      map[nmap].value = memcpy (&string_space[string_space_act],
+					value, value_len);
+	      string_space_act += value_len;
+
+	      ++nmap;
+	      ++added;
+	    }
+	}
+    }
+
+  /* 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 *) realloc (map, (new_size
+						* sizeof (struct alias_map)));
+  if (new_map == NULL)
+    /* Simply don't extend: we don't have any more core.  */
+    return;
+
+  map = new_map;
+  maxmap = new_size;
+}
+
+
+#ifdef _LIBC
+static void __attribute__ ((unused))
+free_mem (void)
+{
+  if (string_space != NULL)
+    free (string_space);
+  if (map != NULL)
+    free (map);
+}
+text_set_element (__libc_subfreeres, free_mem);
+#endif
+
+
+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
+}