# HG changeset patch
# User Olaf Wintermann <olaf.wintermann@gmail.com>
# Date 1689882945 -7200
# Node ID 36a7f2ea7d1263eb7fe9da9251e461b92e3132f7
# Parent  3cfe65695a8c6c8ad13e3594d4568fa1cb775dd4
add error logging

diff -r 3cfe65695a8c -r 36a7f2ea7d12 dav/error.c
--- a/dav/error.c	Thu Jul 20 21:16:19 2023 +0200
+++ b/dav/error.c	Thu Jul 20 21:55:45 2023 +0200
@@ -34,37 +34,41 @@
 #include "error.h"
 
 void print_resource_error(DavSession *sn, const char *path) {
+    print_resource_error_to_file(stderr, sn, path);
+}
+
+void print_resource_error_to_file(FILE *file, DavSession *sn, const char *path) {
     char *res_url = util_concat_path(sn->base_url, path);
     switch(sn->error) {
         default: {
-            fprintf(stderr, "Operation failed for resource %s.\n", res_url);
+            fprintf(file, "Operation failed for resource %s.\n", res_url);
             if(sn->errorstr) {
-                fprintf(stderr, "%s\n", sn->errorstr);
+                fprintf(file, "%s\n", sn->errorstr);
             }
             break;
         }
         case DAV_NOT_FOUND: {
-            fprintf(stderr, "Resource %s not found.\n", res_url);
+            fprintf(file, "Resource %s not found.\n", res_url);
             break;
         }
         case DAV_UNAUTHORIZED: {
-            fprintf(stderr, "Authentication required.\n");
+            fprintf(file, "Authentication required.\n");
             break;
         }
         case DAV_PROXY_AUTH_REQUIRED: {
-            fprintf(stderr, "Proxy authentication required.\n");
+            fprintf(file, "Proxy authentication required.\n");
             break;
         }
         case DAV_NET_AUTH_REQUIRED: {
-            fprintf(stderr, "Network authentication required.\n");
+            fprintf(file, "Network authentication required.\n");
             break;
         }
         case DAV_FORBIDDEN: {
-            fprintf(stderr, "Access forbidden.\n");
+            fprintf(file, "Access forbidden.\n");
             break;
         }
         case DAV_METHOD_NOT_ALLOWED: {
-            fprintf(stderr, "Method not allowed.\n");
+            fprintf(file, "Method not allowed.\n");
             break;
         }
         case DAV_CONFLICT: {
@@ -81,48 +85,48 @@
             break;
         }
         case DAV_UNSUPPORTED_PROTOCOL: {
-            fprintf(stderr, "Unsupported protocol.\n");
+            fprintf(file, "Unsupported protocol.\n");
             if(sn->errorstr) {
-                fprintf(stderr, "%s\n", sn->errorstr);
+                fprintf(file, "%s\n", sn->errorstr);
             }
             break;
         }
         case DAV_COULDNT_RESOLVE_PROXY: {
-            fprintf(stderr, "Cannot resolve proxy host.\n");
+            fprintf(file, "Cannot resolve proxy host.\n");
             break;
         }
         case DAV_COULDNT_RESOLVE_HOST: {
-            fprintf(stderr, "Cannot resolve host name.\n");
+            fprintf(file, "Cannot resolve host name.\n");
             break;
         }
         case DAV_COULDNT_CONNECT: {
-            fprintf(stderr, "Cannot connect to host.\n");
+            fprintf(file, "Cannot connect to host.\n");
             break;
         }
         case DAV_TIMEOUT: {
-            fprintf(stderr, "Operation timed out.\n");
+            fprintf(file, "Operation timed out.\n");
             break;
         }
         case DAV_SSL_ERROR: {
-            fprintf(stderr, "SSL error.\n");
+            fprintf(file, "SSL error.\n");
             if(sn->errorstr) {
-                fprintf(stderr, "%s\n", sn->errorstr);
+                fprintf(file, "%s\n", sn->errorstr);
             }
             break;
         }
         case DAV_CONTENT_VERIFICATION_ERROR: {
             fprintf(
-                    stderr,
+                    file,
                     "Content checksum verification failed for resource %s.\n",
                     res_url);
             break;
         }
         case DAV_REQUEST_ENTITY_TOO_LARGE: {
-            fprintf(stderr, "Request entity too large.\n");
+            fprintf(file, "Request entity too large.\n");
             break;
         }
         case DAV_REQUEST_URL_TOO_LONG: {
-            fprintf(stderr, "Request URL too long.\n");
+            fprintf(file, "Request URL too long.\n");
             break;
         }
     }
diff -r 3cfe65695a8c -r 36a7f2ea7d12 dav/error.h
--- a/dav/error.h	Thu Jul 20 21:16:19 2023 +0200
+++ b/dav/error.h	Thu Jul 20 21:55:45 2023 +0200
@@ -36,6 +36,7 @@
 #endif
 
 void print_resource_error(DavSession *sn, const char *path);
+void print_resource_error_to_file(FILE *file, DavSession *sn, const char *path);
 
 
 #ifdef __cplusplus
diff -r 3cfe65695a8c -r 36a7f2ea7d12 dav/scfg.c
--- a/dav/scfg.c	Thu Jul 20 21:16:19 2023 +0200
+++ b/dav/scfg.c	Thu Jul 20 21:55:45 2023 +0200
@@ -627,7 +627,7 @@
     dir->collection = collection ? strdup(collection) : NULL;
     dir->repository = strdup(repository);
     dir->database = strdup(database);
-    dir->logfile = strdup(logfile);
+    dir->logfile = logfile ? strdup(logfile) : NULL;
     dir->tagconfig = tagconfig;
     dir->versioning = versioning;
     dir->max_retry = max_retry;
diff -r 3cfe65695a8c -r 36a7f2ea7d12 dav/sync.c
--- a/dav/sync.c	Thu Jul 20 21:16:19 2023 +0200
+++ b/dav/sync.c	Thu Jul 20 21:55:45 2023 +0200
@@ -119,6 +119,13 @@
     va_end(ap);
 }
 
+void log_resource_error(DavSession *sn, const char *path) {
+    print_resource_error(sn, path);
+    if(synclog) {
+        print_resource_error_to_file(synclog, sn, path);
+    }
+}
+
 
 int logfile_open(SyncDirectory *dir) {
     int ret = 0;
@@ -704,9 +711,9 @@
     root->iscollection = TRUE;
     if((dir->lockpush || cmd_getoption(a, "lock")) && !cmd_getoption(a, "nolock")) {
         if(dav_lock_t(root, dir->lock_timeout)) {
-            print_resource_error(sn, "/");
+            log_resource_error(sn, "/");
             dav_session_destroy(sn);
-            fprintf(stderr, "Abort\n");
+            log_error("Abort\n");
             return -1;
         }
         DavLock *lock = dav_get_lock(sn, "/");
@@ -720,16 +727,16 @@
     int ret = 0;
     DavResource *ls = dav_query(sn, "select D:getetag,idav:split,idav:status,`idav:content-hash`,idavprops:tags,idavprops:finfo,idavprops:xattributes,idavprops:link from / with depth = infinity");
     if(!ls) {
-        print_resource_error(sn, "/");
+        log_resource_error(sn, "/");
         if(locked) {
             if(dav_unlock(root)) {
-                print_resource_error(sn, "/");
+                log_resource_error(sn, "/");
             } else {
                 locked = FALSE;
             }
         }
         
-        fprintf(stderr, "Abort\n");
+        log_error("Abort\n");
         
         dav_session_destroy(sn);
         // TODO: free
@@ -739,7 +746,7 @@
         fprintf(stderr, "%s is not a collection.\nAbort.\n", ls->path);
         if(locked) {
             if(dav_unlock(root)) {
-                print_resource_error(sn, "/");
+                log_resource_error(sn, "/");
             } else {
                 locked = FALSE;
             }
@@ -1061,7 +1068,7 @@
     // unlock repository
     if(locked) {
         if(dav_unlock(root)) {
-            print_resource_error(sn, "/");
+            log_resource_error(sn, "/");
             ret = -1;
         } else {
             locked = FALSE;
@@ -2041,9 +2048,9 @@
     
     DavResource *root = dav_query(sn, "select D:getetag,idav:status from / with depth = %d", depth);
     if(!root) {
-        print_resource_error(sn, "/");
+        log_resource_error(sn, "/");
         dav_session_destroy(sn);
-        fprintf(stderr, "Abort\n");
+        log_error("Abort\n");
         return -1;
     }
     
@@ -2060,9 +2067,9 @@
     char *locktokenfile = NULL;
     if((dir->lockpush || cmd_getoption(a, "lock")) && !cmd_getoption(a, "nolock") && !outgoing) {
         if(dav_lock_t(root, dir->lock_timeout)) {
-            print_resource_error(sn, "/");
+            log_resource_error(sn, "/");
             dav_session_destroy(sn);
-            fprintf(stderr, "Abort\n");
+            log_error("Abort\n");
             return -1;
         }
         DavLock *lock = dav_get_lock(sn, "/");
@@ -2164,8 +2171,7 @@
         
         if(local_res->isnew) {
             if(local_resource_load_metadata(dir, local_res)) {
-                fprintf(
-                        stderr,
+                log_error(
                         "Failed to load metadata: %s\n",
                         local_resource_path(local_res));
             }
@@ -2280,7 +2286,7 @@
         
         DavResource *res = dav_resource_new(sn, local_res->path);
         if(!res) {
-            print_resource_error(sn, local_res->path);
+            log_resource_error(sn, local_res->path);
             ret = -1;
             sync_error++;
         }
@@ -2293,7 +2299,7 @@
             // TODO: show 405
             log_printf("mkcol: %s\n", local_res->path);
             if(sync_mkdir(dir, res, local_res) && sn->error != DAV_METHOD_NOT_ALLOWED) {
-                print_resource_error(sn, res->path);
+                log_resource_error(sn, res->path);
                 ret = -1;
                 sync_error++;
                 error = 1;
@@ -2301,7 +2307,7 @@
             }
         } else if(sn->error != DAV_OK) {
             // dav_exists() failed
-            print_resource_error(sn, local_res->path);
+            log_resource_error(sn, local_res->path);
             ret = -1;
             sync_error++;
             error = 1;
@@ -2374,7 +2380,7 @@
 
             if(err) {
                 sync_error++;
-                print_resource_error(sn, res->path);
+                log_resource_error(sn, res->path);
                 ret = -1;
                 error = 1;
             } else {
@@ -2399,7 +2405,7 @@
 
             DavResource *res = dav_resource_new(sn, local_res->path);
             if(!res) {
-                print_resource_error(sn, local_res->path);
+                log_resource_error(sn, local_res->path);
                 ret = -1;
                 sync_error++;
             } else {
@@ -2445,7 +2451,7 @@
                     }
                     if(sync_put_resource(dir, res, local_res, &sync_success)) {
                         sync_error++;
-                        print_resource_error(sn, res->path);
+                        log_resource_error(sn, res->path);
                         ret = -1;
                         error = 1;
 
@@ -2506,7 +2512,7 @@
             }
             if(sync_delete_remote_resource(dir, sn, local, &sync_delete, col_list)) {
                 if(sn->error != DAV_NOT_FOUND) {
-                    print_resource_error(sn, local->path);
+                    log_resource_error(sn, local->path);
                     sync_error++;
                     break;
                 }
@@ -2525,7 +2531,7 @@
     // unlock repository
     if(locked) {
         if(dav_unlock(root)) {
-            print_resource_error(sn, "/");
+            log_resource_error(sn, "/");
             ret = -1;
         } else {
             locked = FALSE;
@@ -2534,7 +2540,7 @@
     
     // store db
     if(store_db(db, dir->database, dir->db_settings)) {
-        fprintf(stderr, "Cannot store sync db\n");
+        log_error("Cannot store sync db\n");
         ret = -2;
     }
     
@@ -2637,7 +2643,7 @@
     
     SyncDatabase *db = load_db(dir->database);
     if(!db) {
-        fprintf(stderr, "Cannot load database file: %s\n", dir->database);
+        log_error("Cannot load database file: %s\n", dir->database);
         return -1;
     }
     remove_deleted_conflicts(dir, db);
@@ -2665,8 +2671,8 @@
                     cxListAdd(deleted, resource);
                 }
             } else {
-                fprintf(stderr, "Cannot stat file: %s\n", file_path);
-                perror("");
+                log_error("Cannot stat file: %s\n", file_path);
+                log_error("%s\n", strerror(errno));
             }
         } else {
             if(files) {
@@ -2692,7 +2698,7 @@
     // create DavSession
     Repository *repo = get_repository(cx_str(dir->repository));
     if(!repo) {
-        fprintf(stderr, "Unkown repository %s\n", dir->name);
+        log_error("Unkown repository %s\n", dir->name);
         return -1;
     }
     DavSession *sn = create_session(a, ctx, repo, dir->collection);
@@ -2709,9 +2715,9 @@
     root->iscollection = TRUE;
     if((dir->lockpush || cmd_getoption(a, "lock")) && !cmd_getoption(a, "nolock")) {
         if(dav_lock_t(root, dir->lock_timeout)) {
-            print_resource_error(sn, "/");
+            log_resource_error(sn, "/");
             dav_session_destroy(sn);
-            fprintf(stderr, "Abort\n");
+            log_error("Abort\n");
             return -1;
         }
         DavLock *lock = dav_get_lock(sn, "/");
@@ -2740,7 +2746,7 @@
             }
             char *status = dav_get_string_property(res, "idav:status");
             if(status && !strcmp(status, "broken")) {
-                fprintf(stderr, "Resource %s broken\n", res->path);
+                log_error("Resource %s broken\n", res->path);
                 continue;
             }
 
@@ -2753,7 +2759,7 @@
                     vres = versioning_deltav_find(res, version);
                 }
                 if(!vres) {
-                    fprintf(stderr, "Cannot find  specified version for resource %s\n", res->path);
+                    log_error("Cannot find specified version for resource %s\n", res->path);
                     ret = 1;
                     break;
                 }
@@ -2772,14 +2778,14 @@
                 if(resource->isdirectory) {
                     char *local_path = create_local_path(dir, res->path);
                     if(sys_mkdir(local_path) && errno != EEXIST) {
-                        fprintf(stderr,
+                        log_error(
                                 "Cannot create directory %s: %s",
                                 local_path, strerror(errno));
                     }
                     free(local_path);
                 } else {
                     if(sync_get_resource(a, dir, res->path, vres, db, update_local_entry, &sync_success)) {
-                        fprintf(stderr, "sync_get_resource failed for resource: %s\n", res->path);
+                        log_error("sync_get_resource failed for resource: %s\n", res->path);
                         sync_error++;
                     } else if(!update_local_entry) {
                         LocalResource *lr = cxMapGet(db->resources, cx_hash_key_str(res->path));
@@ -2798,7 +2804,7 @@
     // unlock repository
     if(locked) {
         if(dav_unlock(root)) {
-            print_resource_error(sn, "/");
+            log_resource_error(sn, "/");
             ret = -1;
         } else {
             locked = FALSE;
@@ -2807,7 +2813,7 @@
     
     // store db
     if(store_db(db, dir->database, dir->db_settings)) {
-        fprintf(stderr, "Cannot store sync db\n");
+        log_error("Cannot store sync db\n");
         ret = -2;
     }
     
@@ -2869,7 +2875,7 @@
     log_printf("%s\n", "File                                                Last Modified    Size");
     log_printf("%s\n", "==============================================================================");
        
-    if(ls_mkcol) {
+    if(ls_mkcol->size > 0) {
         log_printf("Directories:\n");
         CxIterator i = cxListIterator(ls_mkcol);
         cx_foreach(LocalResource *, res, i) {
@@ -2877,7 +2883,7 @@
             total_size += res->size;
         }
     }
-    if(ls_new) {
+    if(ls_new->size > 0) {
         log_printf("New:\n");
         CxIterator i = cxListIterator(ls_new);
         cx_foreach(LocalResource *, res, i) {
@@ -2885,7 +2891,7 @@
             total_size += res->size;
         }
     }
-    if(ls_modified) {
+    if(ls_modified->size > 0) {
         log_printf("Modified:\n");
         CxIterator i = cxListIterator(ls_modified);
         cx_foreach(LocalResource *, res, i) {
@@ -2893,7 +2899,7 @@
             total_size += res->size;
         }
     }
-    if(ls_update) {
+    if(ls_update->size > 0) {
         log_printf("Update:\n");
         CxIterator i = cxListIterator(ls_update);
         cx_foreach(LocalResource *, res, i) {
@@ -2902,28 +2908,28 @@
             free(lastmodified);
         }
     }
-    if(ls_delete) {
+    if(ls_delete->size > 0) {
         log_printf("Delete:\n");
         CxIterator i = cxListIterator(ls_delete);
         cx_foreach(LocalResource *, res, i) {
             log_printf(" %s\n", res->path+1);
         }
     }
-    if(ls_copy) {
+    if(ls_copy->size > 0) {
         log_printf("Copy:\n");
         CxIterator i = cxListIterator(ls_copy);
         cx_foreach(LocalResource *, res, i) {
             log_printf("%s -> %s\n", res->origin->path+1, res->path);
         }
     }
-    if(ls_move) {
+    if(ls_move->size > 0) {
         log_printf("Move:\n");
         CxIterator i = cxListIterator(ls_move);
         cx_foreach(LocalResource *, res, i) {
             log_printf("%s -> %s\n", res->origin->path+1, res->path);
         }
     }
-    if(ls_conflict) {
+    if(ls_conflict->size > 0) {
         log_printf("Conflict\n");
         CxIterator i = cxListIterator(ls_conflict);
         cx_foreach(LocalResource *, res, i) {
@@ -2962,7 +2968,7 @@
         SYS_DIR local_dir = sys_opendir(local_path);
         
         if(!local_dir) {
-            fprintf(stderr, "Cannot open directory %s\n", local_path);
+            log_error("Cannot open directory %s: %s\n", local_path, strerror(errno));
         } else {
             SysDirEnt *ent;
             while((ent = sys_readdir(local_dir)) != NULL) {
@@ -3001,7 +3007,7 @@
     char *file_path = create_local_path(dir, path);
     SYS_STAT s;
     if(sys_lstat(file_path, &s)) {
-        fprintf(stderr, "Cannot stat file %s\n", file_path);
+        log_error("Cannot stat file %s: %s\n", file_path, strerror(errno));
         free(file_path);
         return NULL;
     }
@@ -3472,7 +3478,7 @@
     
     
     if(dav_load_prop(vcol, defprops, numdefprops)) {
-        print_resource_error(res->session, vcol->path);
+        log_resource_error(res->session, vcol->path);
         dav_resource_free(vcol);
         return NULL;
     }
@@ -3542,7 +3548,7 @@
             t.actime = f.last_modified;
             t.modtime = f.last_modified;
             if(utime(path, &t)) {
-                fprintf(stderr, "utime failed for file: %s : %s\n", path, strerror(errno));
+                log_error("utime failed for file: %s : %s\n", path, strerror(errno));
                 ret = 1;
             } else {
                 local->last_modified = f.last_modified;
@@ -3551,7 +3557,7 @@
         if((dir->metadata & FINFO_MODE) == FINFO_MODE && f.mode_set) {
             // set mode
             if(chmod(path, f.mode)) {
-                fprintf(stderr, "chmod failed for file: %s : %s\n", path, strerror(errno));
+                log_error("chmod failed for file: %s : %s\n", path, strerror(errno));
                 ret = 1;
             } else {
                 local->mode = f.mode;
@@ -3601,7 +3607,7 @@
     for(int i=0;i<nattr;i++) {
         cxmutstr value = xattr->values[i];
         if(xattr_set(path, xattr->names[i], value.ptr, value.length)) {
-            fprintf(stderr,
+            log_error(
                     "Cannot store xattr '%s' for file: %s\n",
                     xattr->names[i],
                     path);
@@ -4064,7 +4070,7 @@
     if(res->exists) {
         if(!res->iscollection) {
             if(dav_delete(res)) {
-                print_resource_error(res->session, res->path);
+                log_resource_error(res->session, res->path);
                 *err = 1;
                 return NULL;
             }
@@ -4074,7 +4080,7 @@
     } else {
         res->iscollection = 1;
         if(dav_create(res)) {
-            print_resource_error(res->session, res->path);
+            log_resource_error(res->session, res->path);
             *err = 1;
             return NULL;
         }
@@ -4083,7 +4089,7 @@
     
     if(!res->href) {
         // this should never happen, but just make sure it doesn't crash
-        fprintf(stderr, "href is NULL\n");
+        log_error("href is NULL\n");
         *err = 1;
         return NULL;
     }
@@ -4100,7 +4106,7 @@
     int nblocks = filesize / blocksize;
     int digits = LOG10((double)nblocks) + 1;
     if(digits > 127) {
-        fprintf(stderr, "Too many parts\n");
+        log_error("Too many parts\n");
         *err = 1;
 	free(buffer);
         return NULL;
@@ -4152,7 +4158,7 @@
             dav_set_content_data(part, buffer, r);
             if(dav_store(part)) {
                 *err = 1;
-                print_resource_error(res->session, part->path);
+                log_resource_error(res->session, part->path);
             } else {
                 // successfully uploaded part
                 
@@ -4193,7 +4199,7 @@
     CxList *updated_parts = cxLinkedListCreateSimple(CX_STORE_POINTERS);
     DavResource *parts = dav_query(res->session, "select D:getetag from %s order by name", res->path);
     if(!parts) {
-        print_resource_error(res->session, parts->path);
+        log_resource_error(res->session, parts->path);
         *err = 1;
         cxMapDestroy(updated_parts_map);
         return NULL;
@@ -4230,7 +4236,7 @@
             
             if(delete_part) {
                 if(dav_delete(part)) {
-                    print_resource_error(part->session, part->path);
+                    log_resource_error(part->session, part->path);
                 }
             }
         }
@@ -4304,8 +4310,7 @@
     
     SYS_STAT s;
     if(sys_stat(local_path, &s)) {
-        fprintf(stderr, "Cannot stat file: %s\n", local_path);
-        perror("");
+        log_error("Cannot stat file: %s: %s\n", local_path, strerror(errno));
         free(local_path);
         return -1;
     }
@@ -4319,7 +4324,7 @@
     
     FILE *in = sys_fopen(local_path, "rb");
     if(!in) {
-        fprintf(stderr, "Cannot open file %s\n", local_path);
+        log_error("Cannot open file %s: %s\n", local_path, strerror(errno));
         free(local_path);
         return -1;
     }
@@ -4368,13 +4373,13 @@
         // versioncontrol (DeltaV only, does nothing with simple versioning)
         if(exists && versioning_init(dir, local, res)) {
             // init failed
-            fprintf(stderr, "Cannot activate versioncontrol for resource: %s\n", res->href);
+            log_error("Cannot activate versioncontrol for resource: %s\n", res->href);
             free(local_path);
             return -1;
         } else {
             int err = versioning_begin(dir, res, &exists, &vend_required);
             if(err) {
-                fprintf(stderr, "Cannot store version for resource: %s\n", res->href);
+                log_error("Cannot store version for resource: %s\n", res->href);
                 free(local_path);
                 return -1;
             }
@@ -4397,7 +4402,7 @@
     
     if(vend_required) {
         if(versioning_end(dir, res)) {
-            fprintf(stderr, "Cannot checkin resource\n");
+            log_error("Cannot checkin resource\n");
             ret = 1;
         }
     }
@@ -4416,7 +4421,7 @@
         if(up_res) {
             // the new content length must be equal or greater than the file size
             if(up_res->contentlength < s.st_size && !issplit && !islink) {
-                fprintf(stderr, "Incomplete Upload: %s\n", local_path);
+                log_error("Incomplete Upload: %s\n", local_path);
                 ret = -1;
                 // try to set the resource status to 'broken'
                 sync_set_status(res, "broken");
@@ -4476,8 +4481,7 @@
     
     SYS_STAT s;
     if(sys_stat(local_path, &s)) {
-        fprintf(stderr, "Cannot stat file: %s\n", local_path);
-        perror("");
+        log_error("Cannot stat file: %s: %s\n", local_path, strerror(errno));
         free(local_path);
         return -1;
     }
@@ -4509,7 +4513,7 @@
     MetadataHashes hashes;
     hashes = sync_set_metadata_properties(dir, up_res->session, up_res, local, TRUE);
     if(dav_store(up_res)) {
-        fprintf(stderr, "Error: cannot store resource metadata\n");
+        log_error("Error: cannot store resource metadata\n");
     }
     
     // get new etag
@@ -4554,7 +4558,7 @@
             log_printf("delete: %s\n", res->path);
             if(dav_delete(res)) {
                 ret = 1;
-                fprintf(stderr, "Cannot delete collection %s\n", res->path);
+                log_error("Cannot delete collection %s\n", res->path);
             } else {
                 (*counter)++;
             }
@@ -4575,16 +4579,14 @@
             int vend_required = 0;
             if(dir->versioning && dir->versioning->always) {
                 if(versioning_delete_begin(dir, res, &exists, &vend_required)) {
-                    fprintf(
-                            stderr,
-                            "Cannot save resource version before deletion\n");
+                    log_error("Cannot save resource version before deletion\n");
                     ret = 1;
                 }
             }
             
             if(!ret && dav_delete(res) && exists) {
                 if(sn->error != DAV_NOT_FOUND) {
-                    fprintf(stderr, "Cannot delete resource %s\n", res->path);
+                    log_error("Cannot delete resource %s\n", res->path);
                     ret = 1;
                 }
             } else {
@@ -4633,7 +4635,7 @@
             p.ns = DAV_PROPS_NS;
             p.name = "tags";
             if(dav_load_prop(res, &p, 1) && sn->error != DAV_NOT_FOUND) {
-                print_resource_error(sn, res->path);
+                log_resource_error(sn, res->path);
             }
             CxList *remote_tags = NULL;
             DavXmlNode *tagsprop = dav_get_property_ns(res, DAV_PROPS_NS, "tags");
@@ -4736,7 +4738,7 @@
     
     int err = 0;
     if(dav_store(res)) {
-        print_resource_error(sn, local->path);
+        log_resource_error(sn, local->path);
         err = 1;
     } else {
         update_metadata_hashes(local, hashes);
@@ -4759,8 +4761,7 @@
                 dc[numdc] = res->path;
                 numdc++;
             } else {
-                fprintf(stderr, "Cannot stat file: %s\n", path);
-                perror("");
+                log_error("Cannot stat file: %s: %s\n", path, strerror(errno));
             }
         }
         free(path);
@@ -4779,11 +4780,11 @@
     cx_foreach(LocalResource *, res, i) {
         if(res->skipped) {
             skipped++;
-            fprintf(stderr, "skipped from push: %s\n", res->path);
+            log_error("skipped from push: %s\n", res->path);
         }
     }
     if(skipped > 0) {
-        fprintf(stderr,
+        log_error(
                 "  To resolve conflict resources skipped by push run dav-sync pull first\n"
                 "  before resolve-conflicts or delete-conflicts.\n\n");
     }
@@ -4791,13 +4792,13 @@
 
 int cmd_resolve_conflicts(CmdArgs *a) {
     if(a->argc != 1) {
-        fprintf(stderr, "Too %s arguments\n", a->argc < 1 ? "few" : "many");
+        log_error("Too %s arguments\n", a->argc < 1 ? "few" : "many");
         return -1;
     }
     
     SyncDirectory *dir = scfg_get_dir(a->argv[0]);
     if(!dir) {
-        fprintf(stderr, "Unknown sync dir: %s\n", a->argv[0]);
+        log_error("Unknown sync dir: %s\n", a->argv[0]);
         return -1;
     }
     if(scfg_check_dir(dir)) {
@@ -4809,7 +4810,7 @@
     
     SyncDatabase *db = load_db(dir->database);
     if(!db) {
-        fprintf(stderr, "Cannot load database file: %s\n", dir->database);
+        log_error("Cannot load database file: %s\n", dir->database);
         return -1;
     }
     
@@ -4824,8 +4825,8 @@
     
     // store db
     if(store_db(db, dir->database, dir->db_settings)) {
-        fprintf(stderr, "Cannot store sync db\n");
-        fprintf(stderr, "Abort\n");
+        log_error("Cannot store sync db\n");
+        log_error("Abort\n");
         ret = -2;
     }
     
@@ -4861,7 +4862,7 @@
     
     SyncDatabase *db = load_db(dir->database);
     if(!db) {
-        fprintf(stderr, "Cannot load database file: %s\n", dir->database);
+        log_error("Cannot load database file: %s\n", dir->database);
         return -1;
     }
     
@@ -4879,7 +4880,7 @@
         char *path = create_local_path(dir, res->path);
         if(sys_unlink(path)) {
             if(errno != ENOENT) {
-                perror("unlink");
+                log_error("unlink: %s", strerror(errno));
                 num_err++;
             }
         } else {
@@ -4892,8 +4893,8 @@
     
     // store db
     if(store_db(db, dir->database, dir->db_settings)) {
-        fprintf(stderr, "Cannot store sync db\n");
-        fprintf(stderr, "Abort\n");
+        log_error("Cannot store sync db\n");
+        log_error("Abort\n");
         ret = -1;
     }
     
@@ -5235,14 +5236,14 @@
     }
     
     if(!syncdir->trash) {
-        fprintf(stderr, "trash not configured for %s\n", syncdir->name);
+        log_error("trash not configured for %s\n", syncdir->name);
         return -1;
     }
     
     SYS_DIR dir = sys_opendir(syncdir->trash);
     if(!dir) {
-        fprintf(stderr, "cannot open trash directory: %s\n", syncdir->trash);
-        perror("opendir");
+        log_error("cannot open trash directory: %s\n", syncdir->trash);
+        log_error("opendir: %s\n", strerror(errno));
         return -1;
     }
     
@@ -5257,17 +5258,17 @@
         
         SYS_STAT s;
         if(sys_stat(path, &s)) {
-            perror("stat");
+            log_error("stat: %s\n", strerror(errno));
             free(path);
             continue;
         }
         if(S_ISDIR(s.st_mode)) {
             if(rmdir(path)) {
-                perror("rmdir");
+                log_error("rmdir: %s\n", strerror(errno));
             }
         } else {
             if(sys_unlink(path)) {
-                perror("unlink");
+                log_error("unlink: %s\n", strerror(errno));
             }
         }
         
@@ -5534,12 +5535,12 @@
 
 void sync_print_get_file_err(const char *path, int err) {
     switch(err) {
-        case 1: fprintf(stderr, "File %s: not found\n", path); break;
-        case 2: fprintf(stderr, "File %s: permission denied\n", path); break;
-        case 3: fprintf(stderr, "File %s: stat failed: %s\n", path, strerror(errno)); break;
-        case 4: fprintf(stderr, "File %s is not in any syncdir\n", path); break;
-        case 5: fprintf(stderr, "File %s is in multiple syncdirs\n", path); break;
-        case 6: fprintf(stderr, "Syncdir not found\n"); break;
+        case 1: log_error("File %s: not found\n", path); break;
+        case 2: log_error("File %s: permission denied\n", path); break;
+        case 3: log_error("File %s: stat failed: %s\n", path, strerror(errno)); break;
+        case 4: log_error("File %s is not in any syncdir\n", path); break;
+        case 5: log_error("File %s is in multiple syncdirs\n", path); break;
+        case 6: log_error("Syncdir not found\n"); break;
     }
 }
 
@@ -5701,11 +5702,11 @@
     
     FILE *file = sys_fopen(path, "w");
     if(file) {
-        fprintf(file, "%s\n", locktoken);
+        log_error("%s\n", locktoken);
         fclose(file);
         return path;
     } else {
-        perror("Cannot create locktoken file");
+        log_error("Cannot create locktoken file: %s", strerror(errno));
         free(path);
         return NULL;
     }