gfileutils.c

嵌入式下基于MiniGUI的Web Browser

                   filename, g_strerror (errno));

      return FALSE;
    }

  /* I don't think this will ever fail, aside from ENOMEM, but. */
  if (fstat (fd, &stat_buf) < 0)
    {
      close (fd);
      
      g_set_error (error,
                   G_FILE_ERROR,
                   g_file_error_from_errno (errno),
                   _("Failed to get attributes of file '%s': fstat() failed: %s"),
                   filename, g_strerror (errno));

      return FALSE;
    }

  if (stat_buf.st_size > 0 && S_ISREG (stat_buf.st_mode))
    {
      return get_contents_regfile (filename,
                                   &stat_buf,
                                   fd,
                                   contents,
                                   length,
                                   error);
    }
  else
    {
      FILE *f;

      f = fdopen (fd, "r");
      
      if (f == NULL)
        {
          g_set_error (error,
                       G_FILE_ERROR,
                       g_file_error_from_errno (errno),
                       _("Failed to open file '%s': fdopen() failed: %s"),
                       filename, g_strerror (errno));
          
          return FALSE;
        }
  
      return get_contents_stdio (filename, f, contents, length, error);
    }
}

#else  /* G_OS_WIN32 */

static gboolean
get_contents_win32 (const gchar *filename,
                    gchar      **contents,
                    gsize       *length,
                    GError     **error)
{
  FILE *f;

  /* I guess you want binary mode; maybe you want text sometimes? */
  f = fopen (filename, "rb");

  if (f == NULL)
    {
      g_set_error (error,
                   G_FILE_ERROR,
                   g_file_error_from_errno (errno),
                   _("Failed to open file '%s': %s"),
                   filename, g_strerror (errno));
      
      return FALSE;
    }
  
  return get_contents_stdio (filename, f, contents, length, error);
}

#endif

/**
 * g_file_get_contents:
 * @filename: a file to read contents from
 * @contents: location to store an allocated string
 * @length: location to store length in bytes of the contents
 * @error: return location for a #GError
 * 
 * Reads an entire file into allocated memory, with good error
 * checking. If @error is set, %FALSE is returned, and @contents is set
 * to %NULL. If %TRUE is returned, @error will not be set, and @contents
 * will be set to the file contents.  The string stored in @contents
 * will be nul-terminated, so for text files you can pass %NULL for the
 * @length argument.  The error domain is #G_FILE_ERROR. Possible
 * error codes are those in the #GFileError enumeration.
 *
 * Return value: %TRUE on success, %FALSE if error is set
 **/
gboolean
g_file_get_contents (const gchar *filename,
                     gchar      **contents,
                     gsize       *length,
                     GError     **error)
{  
  g_return_val_if_fail (filename != NULL, FALSE);
  g_return_val_if_fail (contents != NULL, FALSE);

  *contents = NULL;
  if (length)
    *length = 0;

#ifdef G_OS_WIN32
  return get_contents_win32 (filename, contents, length, error);
#else
  return get_contents_posix (filename, contents, length, error);
#endif
}

/*
 * mkstemp() implementation is from the GNU C library.
 * Copyright (C) 1991,92,93,94,95,96,97,98,99 Free Software Foundation, Inc.
 */
/**
 * g_mkstemp:
 * @tmpl: template filename
 *
 * Opens a temporary file. See the <function>mkstemp()</function> documentation
 * on most UNIX-like systems. This is a portability wrapper, which simply calls 
 * <function>mkstemp()</function> on systems that have it, and implements 
 * it in GLib otherwise.
 *
 * The parameter is a string that should match the rules for
 * <function>mkstemp()</function>, i.e. end in "XXXXXX". The X string will 
 * be modified to form the name of a file that didn't exist.
 *
 * Return value: A file handle (as from <function>open()</function>) to the file
 * opened for reading and writing. The file is opened in binary mode
 * on platforms where there is a difference. The file handle should be
 * closed with <function>close()</function>. In case of errors, -1 is returned.
 */
int
g_mkstemp (char *tmpl)
{
#ifdef HAVE_MKSTEMP
  return mkstemp (tmpl);
#else
  int len;
  char *XXXXXX;
  int count, fd;
  static const char letters[] =
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
  static const int NLETTERS = sizeof (letters) - 1;
  glong value;
  GTimeVal tv;
  static int counter = 0;

  len = strlen (tmpl);
  if (len < 6 || strcmp (&tmpl[len - 6], "XXXXXX"))
    return -1;

  /* This is where the Xs start.  */
  XXXXXX = &tmpl[len - 6];

  /* Get some more or less random data.  */
  g_get_current_time (&tv);
  value = (tv.tv_usec ^ tv.tv_sec) + counter++;

  for (count = 0; count < 100; value += 7777, ++count)
    {
      glong v = value;

      /* Fill in the random bits.  */
      XXXXXX[0] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[1] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[2] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[3] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[4] = letters[v % NLETTERS];
      v /= NLETTERS;
      XXXXXX[5] = letters[v % NLETTERS];

      fd = open (tmpl, O_RDWR | O_CREAT | O_EXCL | O_BINARY, 0600);

      if (fd >= 0)
	return fd;
      else if (errno != EEXIST)
	/* Any other error will apply also to other names we might
	 *  try, and there are 2^32 or so of them, so give up now.
	 */
	return -1;
    }

  /* We got out of the loop because we ran out of combinations to try.  */
  return -1;
#endif
}

/**
 * g_file_open_tmp:
 * @tmpl: Template for file name, as in g_mkstemp(), basename only
 * @name_used: location to store actual name used
 * @error: return location for a #GError
 *
 * Opens a file for writing in the preferred directory for temporary
 * files (as returned by g_get_tmp_dir()). 
 *
 * @tmpl should be a string ending with six 'X' characters, as the
 * parameter to g_mkstemp() (or <function>mkstemp()</function>). 
 * However, unlike these functions, the template should only be a 
 * basename, no directory components are allowed. If template is %NULL, 
 * a default template is used.
 *
 * Note that in contrast to g_mkstemp() (and <function>mkstemp()</function>) 
 * @tmpl is not modified, and might thus be a read-only literal string.
 *
 * The actual name used is returned in @name_used if non-%NULL. This
 * string should be freed with g_free() when not needed any longer.
 *
 * Return value: A file handle (as from <function>open()</function>) to 
 * the file opened for reading and writing. The file is opened in binary 
 * mode on platforms where there is a difference. The file handle should be
 * closed with <function>close()</function>. In case of errors, -1 is returned 
 * and @error will be set.
 **/
int
g_file_open_tmp (const char *tmpl,
		 char      **name_used,
		 GError    **error)
{
  int retval;
  const char *tmpdir;
  char *sep;
  char *fulltemplate;

  if (tmpl == NULL)
    tmpl = ".XXXXXX";

  if (strchr (tmpl, G_DIR_SEPARATOR)
#ifdef G_OS_WIN32
      || strchr (tmpl, '/')
#endif
				    )
    {
      g_set_error (error,
		   G_FILE_ERROR,
		   G_FILE_ERROR_FAILED,
		   _("Template '%s' invalid, should not contain a '%s'"),
		   tmpl, G_DIR_SEPARATOR_S);

      return -1;
    }
  
  if (strlen (tmpl) < 6 ||
      strcmp (tmpl + strlen (tmpl) - 6, "XXXXXX") != 0)
    {
      g_set_error (error,
		   G_FILE_ERROR,
		   G_FILE_ERROR_FAILED,
		   _("Template '%s' doesn't end with XXXXXX"),
		   tmpl);
      return -1;
    }

  tmpdir = g_get_tmp_dir ();

  if (tmpdir [strlen (tmpdir) - 1] == G_DIR_SEPARATOR)
    sep = "";
  else
    sep = G_DIR_SEPARATOR_S;

  fulltemplate = g_strconcat (tmpdir, sep, tmpl, NULL);

  retval = g_mkstemp (fulltemplate);

  if (retval == -1)
    {
      g_set_error (error,
		   G_FILE_ERROR,
		   g_file_error_from_errno (errno),
		   _("Failed to create file '%s': %s"),
		   fulltemplate, g_strerror (errno));
      g_free (fulltemplate);
      return -1;
    }

  if (name_used)
    *name_used = fulltemplate;
  else
    g_free (fulltemplate);

  return retval;
}

static gchar *
g_build_pathv (const gchar *separator,
	       const gchar *first_element,
	       va_list      args)
{
  GString *result;
  gint separator_len = strlen (separator);
  gboolean is_first = TRUE;
  gboolean have_leading = FALSE;
  const gchar *single_element = NULL;
  const gchar *next_element;
  const gchar *last_trailing = NULL;

  result = g_string_new (NULL);

  next_element = first_element;

  while (TRUE)
    {
      const gchar *element;
      const gchar *start;
      const gchar *end;

      if (next_element)
	{
	  element = next_element;
	  next_element = va_arg (args, gchar *);
	}
      else
	break;

      /* Ignore empty elements */
      if (!*element)
	continue;
      
      start = element;

      if (separator_len)
	{
	  while (start &&
		 strncmp (start, separator, separator_len) == 0)
	    start += separator_len;
      	}

      end = start + strlen (start);
      
      if (separator_len)
	{
	  while (end >= start + separator_len &&
		 strncmp (end - separator_len, separator, separator_len) == 0)
	    end -= separator_len;
	  
	  last_trailing = end;
	  while (last_trailing >= element + separator_len &&
		 strncmp (last_trailing - separator_len, separator, separator_len) == 0)
	    last_trailing -= separator_len;

	  if (!have_leading)
	    {
	      /* If the leading and trailing separator strings are in the
	       * same element and overlap, the result is exactly that element
	       */
	      if (last_trailing <= start)
		single_element = element;
		  
	      g_string_append_len (result, element, start - element);
	      have_leading = TRUE;
	    }
	  else
	    single_element = NULL;
	}

      if (end == start)
	continue;

      if (!is_first)
	g_string_append (result, separator);
      
      g_string_append_len (result, start, end - start);
      is_first = FALSE;
    }

  if (single_element)
    {
      g_string_free (result, TRUE);
      return g_strdup (single_element);
    }
  else
    {
      if (last_trailing)
	g_string_append (result, last_trailing);
  
      return g_string_free (result, FALSE);
    }
}

/**
 * g_build_path:
 * @separator: a string used to separator the elements of the path.
 * @first_element: the first element in the path
 * @Varargs: remaining elements in path
 * 
 * Creates a path from a series of elements using @separator as the
 * separator between elements. At the boundary between two elements,
 * any trailing occurrences of separator in the first element, or
 * leading occurrences of separator in the second element are removed
 * and exactly one copy of the separator is inserted.
 *
 * Empty elements are ignored.
 *
 * The number of leading copies of the separator on the result is
 * the same as the number of leading copies of the separator on
 * the first non-empty element.
 *
 * The number of trailing copies of the separator on the result is
 * the same as the number of trailing copies of the separator on
 * the last non-empty element. (Determination of the number of
 * trailing copies is done without stripping leading copies, so
 * if the separator is <literal>ABA</literal>, <literal>ABABA</literal>
 * has 1 trailing copy.)
 *
 * However, if there is only a single non-empty element, and there
 * are no characters in that element not part of the leading or
 * trailing separators, then the result is exactly the original value
 * of that element.
 *
 * Other than for determination of the number of leading and trailing
 * copies of the separator, elements consisting only of copies
 * of the separator are ignored.
 * 
 * Return value: a newly-allocated string that must be freed with g_free().
 **/
gchar *
g_build_path (const gchar *separator,
	      const gchar *first_element,
	      ...)
{
  gchar *str;
  va_list args;

  g_return_val_if_fail (separator != NULL, NULL);

  va_start (args, first_element);
  str = g_build_pathv (separator, first_element, args);
  va_end (args);

  return str;
}

/**
 * g_build_filename:
 * @first_element: the first element in the path
 * @Varargs: remaining elements in path
 * 
 * Creates a filename from a series of elements using the correct
 * separator for filenames. This function behaves identically
 * to <literal>g_build_path (G_DIR_SEPARATOR_S, first_element, ....)</literal>.
 *
 * No attempt is made to force the resulting filename to be an absolute
 * path. If the first element is a relative path, the result will
 * be a relative path. 
 * 
 * Return value: a newly-allocated string that must be freed with g_free().
 **/
gchar *
g_build_filename (const gchar *first_element, 
		  ...)
{
  gchar *str;
  va_list args;

  va_start (args, first_element);
  str = g_build_pathv (G_DIR_SEPARATOR_S, first_element, args);
  va_end (args);

  return str;
}