#endif
+
+static gboolean
+rename_file (const char *old_name,
+ const char *new_name,
+ GError **err)
+{
+ errno = 0;
+ if (g_rename (old_name, new_name) == -1)
+ {
+ int save_errno = errno;
+ gchar *display_old_name = g_filename_display_name (old_name);
+ gchar *display_new_name = g_filename_display_name (new_name);
+
+ g_set_error (err,
+ G_FILE_ERROR,
+ g_file_error_from_errno (save_errno),
+ _("Failed to rename file '%s' to '%s': g_rename() failed: %s"),
+ display_old_name,
+ display_new_name,
+ g_strerror (save_errno));
+
+ g_free (display_old_name);
+ g_free (display_new_name);
+
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+static gchar *
+write_to_temp_file (const gchar *contents,
+ gsize length,
+ const gchar *template,
+ GError **err)
+{
+ gchar *tmp_name;
+ gchar *display_name;
+ gchar *retval;
+ FILE *file;
+ gint fd;
+ int save_errno;
+
+ retval = NULL;
+
+ tmp_name = g_strdup_printf (".%s.XXXXXX", template);
+
+ errno = 0;
+ fd = g_mkstemp (tmp_name);
+ save_errno = errno;
+ display_name = g_filename_display_name (tmp_name);
+
+ if (fd == -1)
+ {
+ g_set_error (err,
+ G_FILE_ERROR,
+ g_file_error_from_errno (save_errno),
+ _("Failed to create file '%s': %s"),
+ display_name, g_strerror (save_errno));
+
+ goto out;
+ }
+
+ errno = 0;
+ file = fdopen (fd, "wb");
+ if (!file)
+ {
+ g_set_error (err,
+ G_FILE_ERROR,
+ g_file_error_from_errno (errno),
+ _("Failed to open file '%s' for writing: fdopen() failed: %s"),
+ display_name,
+ g_strerror (errno));
+
+ close (fd);
+ g_unlink (tmp_name);
+
+ goto out;
+ }
+
+ if (length > 0)
+ {
+ size_t n_written;
+
+ errno = 0;
+
+ n_written = fwrite (contents, 1, length, file);
+
+ if (n_written < length)
+ {
+ g_set_error (err,
+ G_FILE_ERROR,
+ g_file_error_from_errno (errno),
+ _("Failed to write file '%s': fwrite() failed: %s"),
+ display_name,
+ g_strerror (errno));
+
+ fclose (file);
+ g_unlink (tmp_name);
+
+ goto out;
+ }
+ }
+
+ errno = 0;
+ if (fclose (file) == EOF)
+ {
+ g_set_error (err,
+ G_FILE_ERROR,
+ g_file_error_from_errno (errno),
+ _("Failed to close file '%s': fclose() failed: %s"),
+ display_name,
+ g_strerror (errno));
+
+ g_unlink (tmp_name);
+
+ goto out;
+ }
+
+ retval = g_strdup (tmp_name);
+
+ out:
+ g_free (tmp_name);
+ g_free (display_name);
+
+ return retval;
+}
+
+/**
+ * g_file_replace:
+ * @filename: name of a file to write @contents to, in the GLib file name
+ * encoding
+ * @contents: string to write to the file
+ * @length: length of @contents, or -1 if @contents is a nul-terminated string
+ * @error: return location for a #GError, or %NULL
+ *
+ * Writes all of @contents to a file named @filename, with good error checking.
+ * If a file called @filename already exists it will be overwritten.
+ *
+ * This write is atomic in the sense that it is first written to a temporary
+ * file which is then renamed to the final name. Notes:
+ * <itemizedlist>
+ * <listitem>
+ * On Unix, if @filename already exists hard links to @filename will break.
+ * Also since the file is recreated, existing permissions, access control
+ * lists, metadata etc. may be lost.
+ * </listitem>
+ * <listitem>
+ * On Windows renaming a file will not remove an existing file with the
+ * new name, so on Windows there is a race condition between the existing
+ * file being removed and the temporary file being renamed.
+ * </listitem>
+ * <listitem>
+ * On Windows there is no way to remove a file that is open to some
+ * process, or mapped into memory. Thus, this function will fail if
+ * @filename already exists and is open.
+ * </listitem>
+ * </itemizedlist>
+ *
+ * If the call was sucessful, it returns %TRUE. If the call was not successful,
+ * it returns %FALSE and sets @error. The error domain is #G_FILE_ERROR.
+ * Possible error codes are those in the #GFileError enumeration.
+ *
+ * Return value: %TRUE on success, %FALSE if an error occurred
+ *
+ * Since: 2.8
+ **/
+gboolean
+g_file_replace (const gchar *filename,
+ const gchar *contents,
+ gssize length,
+ GError **error)
+{
+ char *tmp_filename = NULL;
+ char *display_filename = NULL;
+ char *display_tmpname = NULL;
+ gboolean retval;
+ GError *rename_error = NULL;
+
+ g_return_val_if_fail (filename != NULL, FALSE);
+ g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
+ g_return_val_if_fail (contents != NULL || length == 0, FALSE);
+
+ if (length == -1)
+ length = strlen (contents);
+
+ tmp_filename = write_to_temp_file (contents, length, filename, error);
+
+ if (!tmp_filename)
+ {
+ retval = FALSE;
+ goto out;
+ }
+
+ display_tmpname = g_filename_display_name (tmp_filename);
+ display_filename = g_filename_display_name (filename);
+
+ if (!rename_file (tmp_filename, filename, &rename_error))
+ {
+#ifndef G_OS_WIN32
+
+ g_unlink (tmp_filename);
+ g_propagate_error (error, rename_error);
+ retval = FALSE;
+ goto out;
+
+#else /* G_OS_WIN32 */
+
+ /* Renaming failed, but on Windows this may just mean
+ * the file already exists. So if the target file
+ * exists, try deleting it and do the rename again.
+ */
+ if (!g_file_test (filename, G_FILE_TEST_EXISTS))
+ {
+ g_unlink (tmp_filename);
+ g_propagate_error (error, rename_error);
+ retval = FALSE;
+ goto out;
+ }
+
+ g_error_free (rename_error);
+
+ if (g_unlink (filename) == -1)
+ {
+ g_set_error (error,
+ G_FILE_ERROR,
+ g_file_error_from_errno (errno),
+ _("Existing file '%s' could not be removed: g_unlink() failed: %s"),
+ display_filename,
+ g_strerror (errno));
+
+ g_unlink (tmp_filename);
+ retval = FALSE;
+ goto out;
+ }
+
+ if (!rename_file (tmp_filename, filename, error))
+ {
+ g_unlink (tmp_filename);
+ retval = FALSE;
+ goto out;
+ }
+
+#endif
+ }
+
+ retval = TRUE;
+
+ out:
+ g_free (display_tmpname);
+ g_free (display_filename);
+ g_free (tmp_filename);
+ return retval;
+}
+
/*
* mkstemp() implementation is from the GNU C library.
* Copyright (C) 1991,92,93,94,95,96,97,98,99 Free Software Foundation, Inc.
projects / platform / upstream / glib.git / commitdiff