nextcloud-desktop/csync/src/csync_reconcile.c
2014-10-21 11:47:18 +02:00

355 lines
13 KiB
C

/*
* libcsync -- a library to sync a directory with another
*
* Copyright (c) 2008-2013 by Andreas Schneider <asn@cryptomilk.org>
*
* This 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.
*
* This 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 this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config_csync.h"
#include "csync_private.h"
#include "csync_reconcile.h"
#include "csync_util.h"
#include "csync_statedb.h"
#include "csync_rename.h"
#include "c_jhash.h"
#define CSYNC_LOG_CATEGORY_NAME "csync.reconciler"
#include "csync_log.h"
#include "inttypes.h"
#define ACCEPTED_TIME_DIFF 5
#define ONE_HOUR 3600
/* Check if a file is ignored because one parent is ignored.
* return the node of the ignored directoy if it's the case, or NULL if it is not ignored */
static c_rbnode_t *_csync_check_ignored(c_rbtree_t *tree, const char *path, int pathlen) {
uint64_t h = 0;
c_rbnode_t *node = NULL;
/* compute the size of the parent directory */
int parentlen = pathlen - 1;
while (parentlen > 0 && path[parentlen] != '/') {
parentlen--;
}
if (parentlen <= 0) {
return NULL;
}
h = c_jhash64((uint8_t *) path, parentlen, 0);
node = c_rbtree_find(tree, &h);
if (node) {
csync_file_stat_t *n = (csync_file_stat_t*)node->data;
if (n->instruction == CSYNC_INSTRUCTION_IGNORE) {
/* Yes, we are ignored */
return node;
} else {
/* Not ignored */
return NULL;
}
} else {
/* Try if the parent itself is ignored */
return _csync_check_ignored(tree, path, parentlen);
}
}
/*
* 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_file_stat_t *tmp = NULL;
uint64_t h = 0;
int len = 0;
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_REPLICA:
tree = ctx->local.tree;
break;
default:
break;
}
node = c_rbtree_find(tree, &cur->phash);
if (!node) {
/* Check the renamed path as well. */
char *renamed_path = csync_rename_adjust_path(ctx, cur->path);
if (!c_streq(renamed_path, cur->path)) {
len = strlen( renamed_path );
h = c_jhash64((uint8_t *) renamed_path, len, 0);
node = c_rbtree_find(tree, &h);
}
SAFE_FREE(renamed_path);
}
if (!node) {
/* Check if it is ignored */
node = _csync_check_ignored(tree, cur->path, cur->pathlen);
/* If it is ignored, other->instruction will be IGNORE so this one will also be ignored */
}
/* 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:
if (cur->has_ignored_files) {
/* Do not remove a directory that has ignored files */
break;
}
if (cur->child_modified) {
/* re-create directory that has modified contents */
cur->instruction = CSYNC_INSTRUCTION_NEW;
break;
}
cur->instruction = CSYNC_INSTRUCTION_REMOVE;
break;
case CSYNC_INSTRUCTION_EVAL_RENAME:
if(ctx->current == LOCAL_REPLICA ) {
/* use the old name to find the "other" node */
tmp = csync_statedb_get_stat_by_inode(ctx, cur->inode);
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE, "Finding opposite temp through inode %" PRIu64 ": %s",
cur->inode, tmp ? "true":"false");
} else if( ctx->current == REMOTE_REPLICA ) {
tmp = csync_statedb_get_stat_by_file_id(ctx, cur->file_id);
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE, "Finding opposite temp through file ID %s: %s",
cur->file_id, tmp ? "true":"false");
} else {
CSYNC_LOG(CSYNC_LOG_PRIORITY_DEBUG, "Unknown replica...");
}
if( tmp ) {
if( tmp->path ) {
len = strlen( tmp->path );
h = c_jhash64((uint8_t *) tmp->path, len, 0);
/* First, check that the file is NOT in our tree (another file with the same name was added) */
node = c_rbtree_find(ctx->current == REMOTE_REPLICA ? ctx->remote.tree : ctx->local.tree, &h);
if (node) {
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE, "Origin found in our tree : %s", tmp->path);
} else {
/* Find the temporar file in the other tree. */
node = c_rbtree_find(tree, &h);
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE, "PHash of temporary opposite (%s): %" PRIu64 " %s",
tmp->path , h, node ? "found": "not found" );
if (node) {
other = (csync_file_stat_t*)node->data;
} else {
/* the renamed file could not be found in the opposite tree. That is because it
* is not longer existing there, maybe because it was renamed or deleted.
* The journal is cleaned up later after propagation.
*/
}
}
}
if(!other) {
cur->instruction = CSYNC_INSTRUCTION_NEW;
} else if (other->instruction == CSYNC_INSTRUCTION_NONE
|| cur->type == CSYNC_FTW_TYPE_DIR) {
other->instruction = CSYNC_INSTRUCTION_RENAME;
other->destpath = c_strdup( cur->path );
if( !c_streq(cur->file_id, "") ) {
csync_vio_set_file_id( other->file_id, cur->file_id );
}
other->inode = cur->inode;
other->should_update_etag = true;
cur->instruction = CSYNC_INSTRUCTION_NONE;
} else if (other->instruction == CSYNC_INSTRUCTION_REMOVE) {
other->instruction = CSYNC_INSTRUCTION_RENAME;
other->destpath = c_strdup( cur->path );
if( !c_streq(cur->file_id, "") ) {
csync_vio_set_file_id( other->file_id, cur->file_id );
}
other->inode = cur->inode;
other->should_update_etag = true;
cur->instruction = CSYNC_INSTRUCTION_NONE;
} else if (other->instruction == CSYNC_INSTRUCTION_NEW) {
CSYNC_LOG(CSYNC_LOG_PRIORITY_TRACE, "OOOO=> NEW detected in other tree!");
cur->instruction = CSYNC_INSTRUCTION_CONFLICT;
} else {
cur->instruction = CSYNC_INSTRUCTION_NONE;
other->instruction = CSYNC_INSTRUCTION_SYNC;
}
csync_file_stat_free(tmp);
}
break;
default:
break;
}
} else {
bool is_equal_files = false;
/*
* file found on the other replica
*/
other = (csync_file_stat_t *) node->data;
switch (cur->instruction) {
case CSYNC_INSTRUCTION_EVAL_RENAME:
/* If the file already exist on the other side, we have a conflict.
Abort the rename and consider it is a new file. */
cur->instruction = CSYNC_INSTRUCTION_NEW;
/* fall trough */
/* file on current replica is changed or new */
case CSYNC_INSTRUCTION_EVAL:
case CSYNC_INSTRUCTION_NEW:
// This operation is usually a no-op and will by default return false
if (csync_file_locked_or_open(ctx->local.uri, cur->path)) {
CSYNC_LOG(CSYNC_LOG_PRIORITY_DEBUG, "[Reconciler] IGNORING file %s/%s since it is locked / open", ctx->local.uri, cur->path);
cur->instruction = CSYNC_INSTRUCTION_ERROR;
if (cur->error_status == CSYNC_STATUS_OK) // don't overwrite error
cur->error_status = CYSNC_STATUS_FILE_LOCKED_OR_OPEN;
break;
} else {
//CSYNC_LOG(CSYNC_LOG_PRIORITY_DEBUG, "[Reconciler] not ignoring file %s/%s", ctx->local.uri, cur->path);
}
switch (other->instruction) {
/* file on other replica is changed or new */
case CSYNC_INSTRUCTION_NEW:
case CSYNC_INSTRUCTION_EVAL:
if (other->type == CSYNC_FTW_TYPE_DIR &&
cur->type == CSYNC_FTW_TYPE_DIR) {
is_equal_files = (other->modtime == cur->modtime);
} else {
is_equal_files = ((other->size == cur->size) && (other->modtime == cur->modtime));
}
if (is_equal_files) {
/* The files are considered equal. */
cur->instruction = CSYNC_INSTRUCTION_NONE;
other->instruction = CSYNC_INSTRUCTION_NONE;
/* update DB with new etag from remote */
if (ctx->current == LOCAL_REPLICA) {
other->should_update_etag = true;
} else {
cur->should_update_etag = true;
}
} else if(ctx->current == REMOTE_REPLICA) {
cur->instruction = CSYNC_INSTRUCTION_CONFLICT;
other->instruction = CSYNC_INSTRUCTION_NONE;
} else {
cur->instruction = CSYNC_INSTRUCTION_NONE;
other->instruction = CSYNC_INSTRUCTION_CONFLICT;
}
break;
/* file on the other replica has not been modified */
case CSYNC_INSTRUCTION_NONE:
cur->instruction = CSYNC_INSTRUCTION_SYNC;
break;
case CSYNC_INSTRUCTION_IGNORE:
cur->instruction = CSYNC_INSTRUCTION_IGNORE;
break;
default:
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_REPLICA:
tree = ctx->remote.tree;
break;
default:
break;
}
rc = c_rbtree_walk(tree, (void *) ctx, _csync_merge_algorithm_visitor);
if( rc < 0 ) {
ctx->status_code = CSYNC_STATUS_RECONCILE_ERROR;
}
return rc;
}
/* vim: set ts=8 sw=2 et cindent: */