glibc/intl/loadmsgcat.c

/* Load needed message catalogs.
   Copyright (C) 1995-1999, 2000, 2001, 2002 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

/* Tell glibc's <string.h> to provide a prototype for mempcpy().
   This must come before <config.h> because <config.h> may include
   <features.h>, and once <features.h> has been included, it's too late.  */
#ifndef _GNU_SOURCE
# define _GNU_SOURCE    1
#endif

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.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

#include <stdlib.h>
#include <string.h>

#if defined HAVE_UNISTD_H || defined _LIBC
# include <unistd.h>
#endif

#ifdef _LIBC
# include <langinfo.h>
# include <locale.h>
#endif

#if (defined HAVE_MMAP && defined HAVE_MUNMAP && !defined DISALLOW_MMAP) \
    || (defined _LIBC && defined _POSIX_MAPPED_FILES)
# include <sys/mman.h>
# undef HAVE_MMAP
# define HAVE_MMAP	1
#else
# undef HAVE_MMAP
#endif

#include "gettext.h"
#include "gettextP.h"
#include "plural-exp.h"

#ifdef _LIBC
# include "../locale/localeinfo.h"
#endif

/* @@ end of prolog @@ */

#ifdef _LIBC
/* Rename the non ISO C functions.  This is required by the standard
   because some ISO C functions will require linking with this object
   file and the name space must not be polluted.  */
# define open   __open
# define close  __close
# define read   __read
# define mmap   __mmap
# define munmap __munmap
#endif

/* For those losing systems which don't have `alloca' we have to add
   some additional code emulating it.  */
#ifdef HAVE_ALLOCA
# define freea(p) /* nothing */
#else
# define alloca(n) malloc (n)
# define freea(p) free (p)
#endif

/* We need a sign, whether a new catalog was loaded, which can be associated
   with all translations.  This is important if the translations are
   cached by one of GCC's features.  */
int _nl_msg_cat_cntr;


/* Initialize the codeset dependent parts of an opened message catalog.
   Return the header entry.  */
const char *
internal_function
_nl_init_domain_conv (domain_file, domain, domainbinding)
     struct loaded_l10nfile *domain_file;
     struct loaded_domain *domain;
     struct binding *domainbinding;
{
  /* Find out about the character set the file is encoded with.
     This can be found (in textual form) in the entry "".  If this
     entry does not exist or if this does not contain the `charset='
     information, we will assume the charset matches the one the
     current locale and we don't have to perform any conversion.  */
  char *nullentry;
  size_t nullentrylen;

  /* Preinitialize fields, to avoid recursion during _nl_find_msg.  */
  domain->codeset_cntr =
    (domainbinding != NULL ? domainbinding->codeset_cntr : 0);
#ifdef _LIBC
  domain->conv = (__gconv_t) -1;
#else
# if HAVE_ICONV
  domain->conv = (iconv_t) -1;
# endif
#endif
  domain->conv_tab = NULL;

  /* Get the header entry.  */
  nullentry = _nl_find_msg (domain_file, domainbinding, "", &nullentrylen);

  if (nullentry != NULL)
    {
#if defined _LIBC || HAVE_ICONV
      const char *charsetstr;

      charsetstr = strstr (nullentry, "charset=");
      if (charsetstr != NULL)
	{
	  size_t len;
	  char *charset;
	  const char *outcharset;

	  charsetstr += strlen ("charset=");
	  len = strcspn (charsetstr, " \t\n");

	  charset = (char *) alloca (len + 1);
# if defined _LIBC || HAVE_MEMPCPY
	  *((char *) mempcpy (charset, charsetstr, len)) = '\0';
# else
	  memcpy (charset, charsetstr, len);
	  charset[len] = '\0';
# endif

	  /* The output charset should normally be determined by the
	     locale.  But sometimes the locale is not used or not correctly
	     set up, so we provide a possibility for the user to override
	     this.  Moreover, the value specified through
	     bind_textdomain_codeset overrides both.  */
	  if (domainbinding != NULL && domainbinding->codeset != NULL)
	    outcharset = domainbinding->codeset;
	  else
	    {
	      outcharset = getenv ("OUTPUT_CHARSET");
	      if (outcharset == NULL || outcharset[0] == '\0')
		{
# ifdef _LIBC
		  outcharset = (*_nl_current[LC_CTYPE])->values[_NL_ITEM_INDEX (CODESET)].string;
# else
#  if HAVE_ICONV
		  extern const char *locale_charset (void);
		  outcharset = locale_charset ();
#  endif
# endif
		}
	    }

# ifdef _LIBC
	  /* We always want to use transliteration.  */
	  outcharset = norm_add_slashes (outcharset, "TRANSLIT");
	  charset = norm_add_slashes (charset, NULL);
	  if (__gconv_open (outcharset, charset, &domain->conv,
			    GCONV_AVOID_NOCONV)
	      != __GCONV_OK)
	    domain->conv = (__gconv_t) -1;
# else
#  if HAVE_ICONV
	  /* When using GNU libc >= 2.2 or GNU libiconv >= 1.5,
	     we want to use transliteration.  */
#   if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 2) || __GLIBC__ > 2 \
       || _LIBICONV_VERSION >= 0x0105
	  len = strlen (outcharset);
	  if (len < 10 || strcmp (outcharset + len - 9, "/TRANSLIT") != 0)
	    {
	      char *tmp = (char *) alloca (len + 10 + 1);
	      memcpy (tmp, outcharset, len);
	      memcpy (tmp + len, "//TRANSLIT", 10 + 1);
	      outcharset = tmp;
	    }
#   endif
	  domain->conv = iconv_open (outcharset, charset);
#   if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 2) || __GLIBC__ > 2 \
       || _LIBICONV_VERSION >= 0x0105
	  freea (outcharset);
#   endif
#  endif
# endif

	  freea (charset);
	}
#endif /* _LIBC || HAVE_ICONV */
    }

  return nullentry;
}

/* Frees the codeset dependent parts of an opened message catalog.  */
void
internal_function
_nl_free_domain_conv (domain)
     struct loaded_domain *domain;
{
  if (domain->conv_tab != NULL && domain->conv_tab != (char **) -1)
    free (domain->conv_tab);

#ifdef _LIBC
  if (domain->conv != (__gconv_t) -1)
    __gconv_close (domain->conv);
#else
# if HAVE_ICONV
  if (domain->conv != (iconv_t) -1)
    iconv_close (domain->conv);
# endif
#endif
}

/* Load the message catalogs specified by FILENAME.  If it is no valid
   message catalog do nothing.  */
void
internal_function
_nl_load_domain (domain_file, domainbinding)
     struct loaded_l10nfile *domain_file;
     struct binding *domainbinding;
{
  int fd;
  size_t size;
#ifdef _LIBC
  struct stat64 st;
#else
  struct stat st;
#endif
  struct mo_file_header *data = (struct mo_file_header *) -1;
  int use_mmap = 0;
  struct loaded_domain *domain;
  const char *nullentry;

  domain_file->decided = 1;
  domain_file->data = NULL;

  /* Note that it would be useless to store domainbinding in domain_file
     because domainbinding might be == NULL now but != NULL later (after
     a call to bind_textdomain_codeset).  */

  /* If the record does not represent a valid locale the FILENAME
     might be NULL.  This can happen when according to the given
     specification the locale file name is different for XPG and CEN
     syntax.  */
  if (domain_file->filename == NULL)
    return;

  /* Try to open the addressed file.  */
  fd = open (domain_file->filename, O_RDONLY);
  if (fd == -1)
    return;

  /* We must know about the size of the file.  */
  if (
#ifdef _LIBC
      __builtin_expect (fstat64 (fd, &st) != 0, 0)
#else
      __builtin_expect (fstat (fd, &st) != 0, 0)
#endif
      || __builtin_expect ((size = (size_t) st.st_size) != st.st_size, 0)
      || __builtin_expect (size < sizeof (struct mo_file_header), 0))
    {
      /* Something went wrong.  */
      close (fd);
      return;
    }

#ifdef HAVE_MMAP
  /* Now we are ready to load the file.  If mmap() is available we try
     this first.  If not available or it failed we try to load it.  */
  data = (struct mo_file_header *) mmap (NULL, size, PROT_READ,
					 MAP_PRIVATE, fd, 0);

  if (__builtin_expect (data != (struct mo_file_header *) -1, 1))
    {
      /* mmap() call was successful.  */
      close (fd);
      use_mmap = 1;
    }
#endif

  /* If the data is not yet available (i.e. mmap'ed) we try to load
     it manually.  */
  if (data == (struct mo_file_header *) -1)
    {
      size_t to_read;
      char *read_ptr;

      data = (struct mo_file_header *) malloc (size);
      if (data == NULL)
	return;

      to_read = size;
      read_ptr = (char *) data;
      do
	{
	  long int nb = (long int) read (fd, read_ptr, to_read);
	  if (nb <= 0)
	    {
#ifdef EINTR
	      if (nb == -1 && errno == EINTR)
		continue;
#endif
	      close (fd);
	      return;
	    }
	  read_ptr += nb;
	  to_read -= nb;
	}
      while (to_read > 0);

      close (fd);
    }

  /* Using the magic number we can test whether it really is a message
     catalog file.  */
  if (__builtin_expect (data->magic != _MAGIC && data->magic != _MAGIC_SWAPPED,
			0))
    {
      /* The magic number is wrong: not a message catalog file.  */
#ifdef HAVE_MMAP
      if (use_mmap)
	munmap ((caddr_t) data, size);
      else
#endif
	free (data);
      return;
    }

  domain = (struct loaded_domain *) malloc (sizeof (struct loaded_domain));
  if (domain == NULL)
    return;
  domain_file->data = domain;

  domain->data = (char *) data;
  domain->use_mmap = use_mmap;
  domain->mmap_size = size;
  domain->must_swap = data->magic != _MAGIC;

  /* Fill in the information about the available tables.  */
  switch (W (domain->must_swap, data->revision))
    {
    case 0:
      domain->nstrings = W (domain->must_swap, data->nstrings);
      domain->orig_tab = (struct string_desc *)
	((char *) data + W (domain->must_swap, data->orig_tab_offset));
      domain->trans_tab = (struct string_desc *)
	((char *) data + W (domain->must_swap, data->trans_tab_offset));
      domain->hash_size = W (domain->must_swap, data->hash_tab_size);
      domain->hash_tab = (nls_uint32 *)
	((char *) data + W (domain->must_swap, data->hash_tab_offset));
      break;
    default:
      /* This is an invalid revision.  */
#ifdef HAVE_MMAP
      if (use_mmap)
	munmap ((caddr_t) data, size);
      else
#endif
	free (data);
      free (domain);
      domain_file->data = NULL;
      return;
    }

  /* Now initialize the character set converter from the character set
     the file is encoded with (found in the header entry) to the domain's
     specified character set or the locale's character set.  */
  nullentry = _nl_init_domain_conv (domain_file, domain, domainbinding);

  /* Also look for a plural specification.  */
  EXTRACT_PLURAL_EXPRESSION (nullentry, &domain->plural, &domain->nplurals);
}


#ifdef _LIBC
void
internal_function
_nl_unload_domain (domain)
     struct loaded_domain *domain;
{
  if (domain->plural != &__gettext_germanic_plural)
    __gettext_free_exp (domain->plural);

  _nl_free_domain_conv (domain);

# ifdef _POSIX_MAPPED_FILES
  if (domain->use_mmap)
    munmap ((caddr_t) domain->data, domain->mmap_size);
  else
# endif	/* _POSIX_MAPPED_FILES */
    free ((void *) domain->data);

  free (domain);
}
#endif