/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* camel-cache-map.c : functions for a local<->remote uid map */
/*
* Authors:
* Dan Winship <danw@helixcode.com>
*
* Copyright (C) 2000 Helix Code, Inc. (www.helixcode.com)
*
* 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 of the
* License, 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
*/
#include "camel-cache-map.h"
#include <camel/camel-exception.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
/**
* camel_cache_map_new:
*
* Return value: a new CamelCacheMap
**/
CamelCacheMap *
camel_cache_map_new (void)
{
CamelCacheMap *map = g_new (CamelCacheMap, 1);
map->l2r = g_hash_table_new (g_str_hash, g_str_equal);
map->r2l = g_hash_table_new (g_str_hash, g_str_equal);
return map;
}
static void
free_mapping (gpointer key, gpointer value, gpointer data)
{
g_free (key);
g_free (data);
}
/**
* camel_cache_map_destroy:
* @map: a CamelCacheMap
*
* Frees @map and all of the data stored in it.
**/
void
camel_cache_map_destroy (CamelCacheMap *map)
{
g_hash_table_foreach (map->l2r, free_mapping, NULL);
g_hash_table_destroy (map->l2r);
g_hash_table_destroy (map->r2l);
g_free (map);
}
/**
* camel_cache_map_add:
* @map: a CamelCacheMap
* @luid: the local uid
* @ruid: the remote uid
*
* Adds a mapping between @luid and @ruid. If either already exists
* in the map, this may leak memory and result in incorrect map entries.
* Use camel_cache_map_update() in that case instead.
**/
void
camel_cache_map_add (CamelCacheMap *map, const char *luid, const char *ruid)
{
char *map_luid = g_strdup (luid);
char *map_ruid = g_strdup (ruid);
g_hash_table_insert (map->l2r, map_luid, map_ruid);
g_hash_table_insert (map->r2l, map_ruid, map_luid);
}
/**
* camel_cache_map_remove:
* @map: a CamelCacheMap
* @luid: the local uid
* @ruid: the remote uid
*
* Removes the mapping between @luid and @ruid. Either (but not both)
* of the uids can be %NULL if they are not both known.
**/
void
camel_cache_map_remove (CamelCacheMap *map, const char *luid, const char *ruid)
{
gpointer map_luid, map_ruid;
if ((luid && g_hash_table_lookup_extended (map->l2r, luid,
&map_luid, &map_ruid)) ||
(ruid && g_hash_table_lookup_extended (map->r2l, ruid,
&map_luid, &map_ruid))) {
g_hash_table_remove (map->l2r, map_luid);
g_hash_table_remove (map->r2l, map_ruid);
g_free (map_luid);
g_free (map_ruid);
}
}
/**
* camel_cache_map_update:
* @map: a CamelCacheMap
* @luid: the local uid
* @ruid: the remote uid
*
* Updates the mappings to associate @luid with @ruid, clearing any
* previous mappings for both of them.
**/
void
camel_cache_map_update (CamelCacheMap *map, const char *luid, const char *ruid)
{
camel_cache_map_remove (map, luid, ruid);
camel_cache_map_add (map, luid, ruid);
}
/**
* camel_cache_map_get_local
* @map: a CamelCacheMap
* @ruid: the remote uid
*
* Return value: the corresponding local uid, or %NULL
**/
const char *
camel_cache_map_get_local (CamelCacheMap *map, const char *ruid)
{
return g_hash_table_lookup (map->r2l, ruid);
}
/**
* camel_cache_map_get_remote
* @map: a CamelCacheMap
* @luid: the local uid
*
* Return value: the corresponding remote uid, or %NULL
**/
const char *
camel_cache_map_get_remote (CamelCacheMap *map, const char *luid)
{
return g_hash_table_lookup (map->l2r, luid);
}
static void
write_mapping (gpointer key, gpointer value, gpointer user_data)
{
int fd = *(int *)user_data;
/* FIXME: We assume the local UID has no ':'s in it. */
write (fd, key, strlen (key));
write (fd, ":", 1);
write (fd, value, strlen (value));
write (fd, "\n", 1);
}
/**
* camel_cache_map_write:
* @map: a CamelCacheMap
* @file: the filename to write the map to
* @ex: a CamelException
*
* Writes @map out to @file, setting @ex if something goes wrong.
**/
void
camel_cache_map_write (CamelCacheMap *map, const char *file,
CamelException *ex)
{
int fd;
char *tmpfile;
tmpfile = g_strdup_printf ("%s~", file);
fd = open (tmpfile, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
if (fd == -1) {
g_free (tmpfile);
camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
"Could not create cache map file: %s",
g_strerror (errno));
return;
}
g_hash_table_foreach (map->l2r, write_mapping, &fd);
if (close (fd) == -1 ||
rename (tmpfile, file) == -1) {
camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
"Could not save cache map file: %s",
g_strerror (errno));
unlink (tmpfile);
}
g_free (tmpfile);
}
/**
* camel_cache_map_read:
* @map: a CamelCacheMap
* @file: the filename to read the map from
* @ex: a CamelException
*
* Reads @map from @file, setting @ex if something goes wrong. @map
* should be a freshly-created CamelCacheMap.
**/
void
camel_cache_map_read (CamelCacheMap *map, const char *file, CamelException *ex)
{
FILE *f;
char buf[1024], *p, *q;
/* FIXME: lazy implementation. We could make this work with
* lines longer than 1024 chars. :)
*/
f = fopen (file, "r");
if (!f) {
camel_exception_setv (ex, CAMEL_EXCEPTION_SYSTEM,
"Could not open cache map file: %s",
g_strerror (errno));
return;
}
while (fgets (buf, sizeof (buf), f)) {
p = strchr (buf, ':');
if (p)
q = strchr (buf, '\n');
if (!p || !q) {
camel_exception_set (ex, CAMEL_EXCEPTION_SYSTEM,
"Bad cache file.");
return;
}
*p++ = *q = '\0';
/* Local uid at buf, remote at p. */
camel_cache_map_add (map, buf, p);
}
fclose (f);
}
