nextcloud-desktop/src/csync_reconcile.c
2012-03-02 17:04:02 +01:00

301 lines
8.7 KiB
C

/*
* libcsync -- a library to sync a directory with another
*
* Copyright (c) 2008 by Andreas Schneider <mail@cynapses.org>
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include "csync_private.h"
#include "csync_reconcile.h"
#include "csync_util.h"
#define CSYNC_LOG_CATEGORY_NAME "csync.reconciler"
#include "csync_log.h"
/*
* We merge replicas at the file level. The merged replica contains the
* superset of files that are on the local machine and server copies of
* the replica. In the case where the same file is in both the local
* and server copy, the file that was modified most recently is used.
* This means that new files are not deleted, and updated versions of
* existing files are not overwritten.
*
* When a file is updated, the merge algorithm compares the destination
* file with the the source file. If the destination file is newer
* (timestamp is newer), it is not overwritten. If both files, on the
* source and the destination, have been changed, the newer file wins.
*/
static int _csync_merge_algorithm_visitor(void *obj, void *data) {
csync_file_stat_t *cur = NULL;
csync_file_stat_t *other = NULL;
CSYNC *ctx = NULL;
c_rbtree_t *tree = NULL;
c_rbnode_t *node = NULL;
cur = (csync_file_stat_t *) obj;
ctx = (CSYNC *) data;
/* we need the opposite tree! */
switch (ctx->current) {
case LOCAL_REPLICA:
tree = ctx->remote.tree;
break;
case REMOTE_REPLCIA:
tree = ctx->local.tree;
break;
default:
break;
}
node = c_rbtree_find(tree, &cur->phash);
/* file only found on current replica */
if (node == NULL) {
switch(cur->instruction) {
/* file has been modified */
case CSYNC_INSTRUCTION_EVAL:
cur->instruction = CSYNC_INSTRUCTION_NEW;
break;
/* file has been removed on the opposite replica */
case CSYNC_INSTRUCTION_NONE:
cur->instruction = CSYNC_INSTRUCTION_REMOVE;
break;
case CSYNC_INSTRUCTION_RENAME:
cur->instruction = CSYNC_INSTRUCTION_NEW;
break;
default:
break;
}
} else {
/*
* file found on the other replica
*/
other = (csync_file_stat_t *) node->data;
switch (cur->instruction) {
/* file on current replica is new */
case CSYNC_INSTRUCTION_NEW:
switch (other->instruction) {
/* file on other replica is new too */
case CSYNC_INSTRUCTION_NEW:
if (cur->modtime > other->modtime) {
if(ctx->options.with_conflict_copys)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,"file new on both, cur is newer PATH=./%s",cur->path);
cur->instruction = CSYNC_INSTRUCTION_CONFLICT;
other->instruction = CSYNC_INSTRUCTION_NONE;
}
else
{
cur->instruction = CSYNC_INSTRUCTION_SYNC;
other->instruction = CSYNC_INSTRUCTION_NONE;
}
} else if (cur->modtime < other->modtime) {
if(ctx->options.with_conflict_copys)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,"file new on both, other is newer PATH=./%s",cur->path);
cur->instruction = CSYNC_INSTRUCTION_NONE;
other->instruction = CSYNC_INSTRUCTION_CONFLICT;
}
else
{
cur->instruction = CSYNC_INSTRUCTION_NONE;
other->instruction = CSYNC_INSTRUCTION_SYNC;
}
} else {
/* file are equal */
cur->instruction = CSYNC_INSTRUCTION_NONE;
other->instruction = CSYNC_INSTRUCTION_NONE;
}
break;
/* file on other replica has changed too */
case CSYNC_INSTRUCTION_EVAL:
/* file on current replica is newer */
if (cur->modtime > other->modtime) {
if(ctx->options.with_conflict_copys)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,"new on cur, modified on other, cur is newer PATH=./%s",cur->path);
cur->instruction = CSYNC_INSTRUCTION_CONFLICT;
}
else
{
cur->instruction = CSYNC_INSTRUCTION_SYNC;
}
} else {
/* file on opposite replica is newer */
if(ctx->options.with_conflict_copys)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,"new on cur, modified on other, other is newer PATH=./%s",cur->path);
cur->instruction = CSYNC_INSTRUCTION_NONE;
}
else
{
cur->instruction = CSYNC_INSTRUCTION_NONE;
}
}
break;
/* file on the other replica has not been modified */
case CSYNC_INSTRUCTION_NONE:
cur->instruction = CSYNC_INSTRUCTION_SYNC;
break;
default:
break;
}
break;
/* file on current replica has been modified */
case CSYNC_INSTRUCTION_EVAL:
switch (other->instruction) {
/* file on other replica is new too */
case CSYNC_INSTRUCTION_NEW:
if (cur->modtime > other->modtime) {
if(ctx->options.with_conflict_copys)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,"modified on cur, new on other, cur is newer PATH=./%s",cur->path);
cur->instruction = CSYNC_INSTRUCTION_CONFLICT;
}
else
{
cur->instruction = CSYNC_INSTRUCTION_SYNC;
}
} else {
if(ctx->options.with_conflict_copys)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,"modified on cur, new on other, other is newer PATH=./%s",cur->path);
cur->instruction = CSYNC_INSTRUCTION_NONE;
}
else
{
cur->instruction = CSYNC_INSTRUCTION_NONE;
}
}
break;
/* file on other replica has changed too */
case CSYNC_INSTRUCTION_EVAL:
/* file on current replica is newer */
if (cur->modtime > other->modtime) {
if(ctx->options.with_conflict_copys)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,"both modified, cur is newer PATH=./%s",cur->path);
cur->instruction = CSYNC_INSTRUCTION_CONFLICT;
other->instruction= CSYNC_INSTRUCTION_NONE;
}
else
{
cur->instruction = CSYNC_INSTRUCTION_SYNC;
}
} else {
/* file on opposite replica is newer */
if(ctx->options.with_conflict_copys)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,"both modified, other is newer PATH=./%s",cur->path);
cur->instruction = CSYNC_INSTRUCTION_NONE;
other->instruction=CSYNC_INSTRUCTION_CONFLICT;
}
else
{
cur->instruction = CSYNC_INSTRUCTION_NONE;
}
}
break;
/* file on the other replica has not been modified */
case CSYNC_INSTRUCTION_NONE:
cur->instruction = CSYNC_INSTRUCTION_SYNC;
break;
default:
break;
}
break;
default:
break;
}
}
//hide instruction NONE messages when log level is set to debug,
//only show these messages on log level trace
if(cur->instruction ==CSYNC_INSTRUCTION_NONE)
{
if(cur->type == CSYNC_FTW_TYPE_DIR)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,
"%-20s dir: %s",
csync_instruction_str(cur->instruction),
cur->path);
}
else
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE,
"%-20s file: %s",
csync_instruction_str(cur->instruction),
cur->path);
}
}
else
{
if(cur->type == CSYNC_FTW_TYPE_DIR)
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_DEBUG,
"%-20s dir: %s",
csync_instruction_str(cur->instruction),
cur->path);
}
else
{
CSYNC_LOG(CSYNC_LOG_PRIORITY_DEBUG,
"%-20s file: %s",
csync_instruction_str(cur->instruction),
cur->path);
}
}
return 0;
}
int csync_reconcile_updates(CSYNC *ctx) {
int rc;
c_rbtree_t *tree = NULL;
switch (ctx->current) {
case LOCAL_REPLICA:
tree = ctx->local.tree;
break;
case REMOTE_REPLCIA:
tree = ctx->remote.tree;
break;
default:
break;
}
rc = c_rbtree_walk(tree, (void *) ctx, _csync_merge_algorithm_visitor);
return rc;
}
/* vim: set ts=8 sw=2 et cindent: */