feat(filter): per-directory merge rules at the receiver; implement e/n/w/- modifiers

src/client/client_manifest.c

@@ -330,9 +330,11 @@ int send_list_only(const Config* config) {
 }
 
 /* Send the delete manifest to the server.  Returns 0 on success, -1 on
-   failure.  It carries FOUR sections: the keep-set paths, the protected
-   excluded prefixes, the --delete-missing-args exact-delete paths, and the
-   destination-relative directories the sender synchronized this run.
+   failure.  It carries FOUR path sections (keep-set paths, protected excluded
+   prefixes, --delete-missing-args exact-delete paths, and the destination-
+   relative directories the sender synchronized this run) followed by the
+   protocol-2.30.0 per-directory filter-rule block (`per_dir_rules`, the rules
+   the scan compiled from each directory's merge files).
    When --delete-excluded is given `protected` is empty: excluded destination
    mirrors are then ordinary extras and are removed.  When
    --delete-missing-args is active `missing_args` holds the destination mirrors
@@ -346,7 +348,8 @@ int send_list_only(const Config* config) {
    frame.  A heavily filtered source whose exclusion list is large therefore
    fails the run cleanly on the receiver rather than being truncated. */
 int send_delete_manifest(int fd, ArrayList* manifest, ArrayList* protected_prefixes,
-                         ArrayList* size_skipped, ArrayList* missing_args, ArrayList* synced_dirs) {
+                         ArrayList* size_skipped, ArrayList* missing_args, ArrayList* synced_dirs,
+                         const FilterRuleList* per_dir_rules) {
   if (!send_status(fd, STATUS_MANIFEST))
     return -1;
   int keep_count = manifest ? manifest->size : 0;
@@ -389,6 +392,11 @@ int send_delete_manifest(int fd, ArrayList* manifest, ArrayList* protected_prefi
     if (!send_wire_str(fd, (char*)synced_dirs->items[i]))
       return -1;
   }
+  /* Protocol 2.30.0: the receiver-side per-directory filter rules discovered by
+     the sender's scan, so the whole-tree commit walker can shield a
+     destination-only entry that matches only a per-directory merge rule. */
+  if (!delete_filter_dir_rules_send(fd, per_dir_rules))
+    return -1;
   return 0;
 }
 
@@ -409,11 +417,11 @@ int send_delete_manifest(int fd, ArrayList* manifest, ArrayList* protected_prefi
 
 bool send_delete_manifest_early(Client* client, ArrayList* manifest, ArrayList* protected_prefixes,
                                 ArrayList* size_skipped, ArrayList* missing_args,
-                                ArrayList* synced_dirs) {
+                                ArrayList* synced_dirs, const FilterRuleList* per_dir_rules) {
   if (!client || !manifest)
     return false;
   if (send_delete_manifest(client->file_descriptor, manifest, protected_prefixes, size_skipped,
-                           missing_args, synced_dirs) != 0)
+                           missing_args, synced_dirs, per_dir_rules) != 0)
     return false;
   Status ack;
   /* The wait is long (up to an hour) and runs inline on this thread: a helper
@@ -497,6 +505,7 @@ int send_dry_run_remote(Config* config) {
   ArrayList* dry_dirs = NULL;
   ArrayList* dry_excluded = NULL;
   ArrayList* dry_size_skipped = NULL;
+  FilterRuleList* dry_per_dir = NULL;
   if (!config_send(client->file_descriptor, config))
     goto dry_fail;
   receive_daemon_motd(client, config);
@@ -509,8 +518,10 @@ int send_dry_run_remote(Config* config) {
     dry_manifest = array_list_create(free);
     dry_dirs = array_list_create(free);
     dry_size_skipped = array_list_create(free);
-    if (!dry_manifest || !dry_dirs || !dry_size_skipped)
+    dry_per_dir = filter_rule_list_create();
+    if (!dry_manifest || !dry_dirs || !dry_size_skipped || !dry_per_dir)
       goto dry_fail;
+    prepared.options.per_dir_rules = dry_per_dir;
     if (!config->delete_excluded) {
       dry_excluded = array_list_create(free);
       if (!dry_excluded)
@@ -612,7 +623,7 @@ int send_dry_run_remote(Config* config) {
   bool early_delete = config->use_delete && config_delete_timing_early(config);
   if (dry_manifest) {
     if (send_delete_manifest(client->file_descriptor, dry_manifest, dry_excluded, dry_size_skipped,
-                             NULL, dry_dirs) != 0)
+                             NULL, dry_dirs, dry_per_dir) != 0)
       goto dry_fail;
     if (early_delete) {
       Status ack;
@@ -672,6 +683,8 @@ dry_fail:
     array_list_delete(dry_excluded);
   if (dry_size_skipped)
     array_list_delete(dry_size_skipped);
+  if (dry_per_dir)
+    filter_rule_list_free(dry_per_dir);
   if (scanner)
     directory_scanner_destroy(scanner);
   prepared_scanner_destroy(&prepared);

src/client/client_send.c

@@ -1033,7 +1033,7 @@ static int send_chunks_multithreaded(void* pipeline_context) {
        and wait for the receiver to delete extras before streaming any data. */
     if (!send_delete_manifest_early(client, context->manifest, context->excluded_paths,
                                     context->size_skipped_paths, context->missing_args,
-                                    context->synced_dirs)) {
+                                    context->synced_dirs, context->per_dir_rules)) {
       pipeline_cancel(context);
       disconnect_transfer_client(client);
       mark_sender_done(context);
@@ -1163,7 +1163,8 @@ static int send_chunks_multithreaded(void* pipeline_context) {
       log_message(LOG_LEVEL_WARNING, "IO error encountered -- skipping file deletion");
     } else if (send_delete_manifest(client->file_descriptor, context->manifest,
                                     context->excluded_paths, context->size_skipped_paths,
-                                    context->missing_args, context->synced_dirs) != 0) {
+                                    context->missing_args, context->synced_dirs,
+                                    context->per_dir_rules) != 0) {
       goto send_fail;
     }
   } else if (context->config->delete_missing_args && !context->early_delete &&
@@ -1171,7 +1172,7 @@ static int send_chunks_multithreaded(void* pipeline_context) {
     /* --delete-missing-args without --delete: no keep-set is built, but the
        exact-delete paths still ride the same manifest frame (commit once the
        transfer succeeded). */
-    if (send_delete_manifest(client->file_descriptor, NULL, NULL, NULL, context->missing_args,
+    if (send_delete_manifest(client->file_descriptor, NULL, NULL, NULL, context->missing_args, NULL,
                              NULL) != 0)
       goto send_fail;
   }
@@ -1285,6 +1286,7 @@ static int scan_directory_multithreaded(void* pipeline_context) {
      its protected lists, so the data pass must not append to them again. */
   if (!context->early_delete && !context->delete_plans) {
     prepared.options.excluded_paths = context->excluded_paths;
+    prepared.options.per_dir_rules = context->per_dir_rules;
     /* The root marker for a full recursive transfer is already in the list; do
        not let the scanner append every directory to it. */
     if (context->config->files_from_set != NULL)
@@ -1518,6 +1520,8 @@ typedef struct {
   ArrayList* synced_dirs;
   ArrayList* plan_dirs;
   ArrayList* missing_args;
+  /* Per-directory filter rules compiled by the scan (protocol 2.30.0). */
+  FilterRuleList* per_dir_rules;
   PreparedScanner prepared;
   StopCondition stop;
   TransferStats transfer_stats;
@@ -1562,9 +1566,11 @@ static bool send_files_prepare(Config* config, SendFilesState* state) {
     }
     state->size_skipped = array_list_create(free);
     state->synced_dirs = array_list_create(free);
-    if (!state->size_skipped || !state->synced_dirs)
+    state->per_dir_rules = filter_rule_list_create();
+    if (!state->size_skipped || !state->synced_dirs || !state->per_dir_rules)
       return false;
     state->prepared.options.size_skipped_paths = state->size_skipped;
+    state->prepared.options.per_dir_rules = state->per_dir_rules;
     /* Only a --files-from subset confines the extras walk to the directories
        the scan synchronized; a full recursive transfer deletes throughout the
        receive root, so mark the root itself (the "." sentinel) and let the
@@ -1629,9 +1635,9 @@ static bool send_files_prepare_delete(Config* config, SendFilesState* state) {
         log_message(LOG_LEVEL_WARNING, "IO error encountered -- skipping file deletion");
         skip_delete = true;
       } else {
-        early_ok =
-            send_delete_manifest_early(client, early_manifest, state->excluded, state->size_skipped,
-                                       state->missing_args, state->synced_dirs);
+        early_ok = send_delete_manifest_early(client, early_manifest, state->excluded,
+                                              state->size_skipped, state->missing_args,
+                                              state->synced_dirs, state->per_dir_rules);
       }
     }
     array_list_delete(early_manifest);
@@ -1640,6 +1646,7 @@ static bool send_files_prepare_delete(Config* config, SendFilesState* state) {
     state->prepared.options.excluded_paths = NULL;
     state->prepared.options.size_skipped_paths = NULL;
     state->prepared.options.synced_dirs = NULL;
+    state->prepared.options.per_dir_rules = NULL;
     if (!prescan_ok || (!early_ok && !skip_delete)) {
       array_list_delete(prescan_chunks);
       return false;
@@ -1669,7 +1676,7 @@ static bool send_files_prepare_delete(Config* config, SendFilesState* state) {
           config->files_from_set ? state->synced_dirs : (walk_root ? state->synced_dirs : NULL);
       delete_plan_sender_finalize(state->plan_sender, scope, walk_root);
       delete_plan_sender_set_config(state->plan_sender, state->excluded, state->size_skipped,
-                                    state->missing_args);
+                                    state->missing_args, state->per_dir_rules);
       if (state->had_scan_io && delete_plan_sender_empty(state->plan_sender)) {
         log_message(LOG_LEVEL_ERROR,
                     "source scan hit an I/O error before finding any file; refusing to delete "
@@ -1693,6 +1700,7 @@ static bool send_files_prepare_delete(Config* config, SendFilesState* state) {
     state->prepared.options.size_skipped_paths = NULL;
     state->prepared.options.synced_dirs = NULL;
     state->prepared.options.plan_dirs = NULL;
+    state->prepared.options.per_dir_rules = NULL;
     if (!prescan_ok || (!plans_ok && !skip_delete))
       return false;
   } else if (config->use_delete) {
@@ -1874,7 +1882,8 @@ static int send_files_finalize(const Config* config, SendFilesState* state) {
          modes the deletion already went out with the data, so nothing is
          re-sent here. */
       if (send_delete_manifest(client->file_descriptor, state->manifest, state->excluded,
-                               state->size_skipped, state->missing_args, state->synced_dirs) != 0) {
+                               state->size_skipped, state->missing_args, state->synced_dirs,
+                               state->per_dir_rules) != 0) {
         if (state->manifest) {
           array_list_delete(state->manifest);
           state->manifest = NULL;
@@ -1949,6 +1958,8 @@ static void send_files_cleanup(SendFilesState* state) {
     array_list_delete(state->plan_dirs);
   if (state->missing_args)
     array_list_delete(state->missing_args);
+  if (state->per_dir_rules)
+    filter_rule_list_free(state->per_dir_rules);
   if (state->remove_sources)
     array_list_delete(state->remove_sources);
   if (state->dir_entries)
@@ -2130,7 +2141,8 @@ static int send_files_multithreaded_impl(Config* config) {
        confined; only a --files-from subset records concrete directories. */
     context->size_skipped_paths = array_list_create(free);
     context->synced_dirs = array_list_create(free);
-    if (!context->size_skipped_paths || !context->synced_dirs) {
+    context->per_dir_rules = filter_rule_list_create();
+    if (!context->size_skipped_paths || !context->synced_dirs || !context->per_dir_rules) {
       pipeline_context_sender_destroy(context);
       return 1;
     }
@@ -2159,6 +2171,7 @@ static int send_files_multithreaded_impl(Config* config) {
         if (context->excluded_paths)
           prepared.options.excluded_paths = context->excluded_paths;
         prepared.options.size_skipped_paths = context->size_skipped_paths;
+        prepared.options.per_dir_rules = context->per_dir_rules;
         /* The root marker for a full recursive transfer is already in the list;
            only a --files-from subset needs the scanner to record directories. */
         if (config->files_from_set != NULL)
@@ -2199,7 +2212,8 @@ static int send_files_multithreaded_impl(Config* config) {
                                                         : (walk_root ? context->synced_dirs : NULL);
         delete_plan_sender_finalize(context->delete_plans, scope, walk_root);
         delete_plan_sender_set_config(context->delete_plans, context->excluded_paths,
-                                      context->size_skipped_paths, context->missing_args);
+                                      context->size_skipped_paths, context->missing_args,
+                                      context->per_dir_rules);
       }
       bool empty = per_dir
                        ? (context->delete_plans && delete_plan_sender_empty(context->delete_plans))

src/client/client_send_internal.h

@@ -102,9 +102,10 @@ int send_dry_run_manifest(const Config* config);
 int send_list_only(const Config* config);
 int send_dry_run_remote(Config* config);
 int send_delete_manifest(int fd, ArrayList* manifest, ArrayList* protected_prefixes,
-                         ArrayList* size_skipped, ArrayList* missing_args, ArrayList* synced_dirs);
+                         ArrayList* size_skipped, ArrayList* missing_args, ArrayList* synced_dirs,
+                         const FilterRuleList* per_dir_rules);
 bool send_delete_manifest_early(Client* client, ArrayList* manifest, ArrayList* protected_prefixes,
                                 ArrayList* size_skipped, ArrayList* missing_args,
-                                ArrayList* synced_dirs);
+                                ArrayList* synced_dirs, const FilterRuleList* per_dir_rules);
 
 #endif

src/client/scanner.h

@@ -115,6 +115,13 @@ typedef struct {
    * directories, exactly like rsync; the receive root is the "." sentinel.
    * Guarded by `excluded_mutex`. */
   ArrayList* synced_dirs;
+  /* Per-directory filter-rule sink (optional): when non-NULL the scanner appends
+   * a deep copy of every rule it reads from a per-directory merge file, each
+   * carrying its owner directory and no-inherit flag (see filter.h).  The delete
+   * carriers transmit them so the receiver re-derives the per-directory
+   * protect/risk set for destination-only entries.  Guarded by `excluded_mutex`
+   * like the other sinks. */
+  FilterRuleList* per_dir_rules;
   /* Delete-plan directory sink (optional): when non-NULL the scanner appends
    * the destination-relative path of every directory it traverses (except the
    * receive root).  The per-directory --delete-during/--delete-delay plan

src/client/scanner_filter.c

@@ -511,13 +511,31 @@ FilterRuleList* read_dir_filters(const ScannerOptions* options, const char* dir_
   }
   if (base) {
     for (int i = 0; i < base->dir_merge_count; i++) {
-      if (!filter_file_append(own, dir_path, base->dir_merge_names[i], rel, &opts, &exists, err,
-                              err_size))
+      if (!filter_dir_merge_append(own, dir_path, &base->dir_merges[i], rel, &opts, &exists, err,
+                                   err_size))
         goto fail;
       if (exists && any_exists)
         *any_exists = true;
     }
   }
+  /* Mirror the directory's rules into the delete-carrier sink so the receiver
+   * can reconstruct its per-directory protect/risk set. */
+  if (options->per_dir_rules && own->count > 0) {
+    mtx_t* mtx = options->excluded_mutex;
+    if (mtx)
+      mtx_lock(mtx);
+    for (int i = 0; i < own->count; i++) {
+      FilterRule* copy = filter_rule_clone(own->items[i]);
+      if (!copy || !filter_rule_list_add(options->per_dir_rules, copy)) {
+        filter_rule_free(copy);
+        if (mtx)
+          mtx_unlock(mtx);
+        goto fail;
+      }
+    }
+    if (mtx)
+      mtx_unlock(mtx);
+  }
   return own;
 fail:
   filter_rule_list_free(own);