Fix --no-i-r-s-u progress: run prescan before fork + track active files

Author: RyuX51

compat.c

@@ -82,7 +82,6 @@ int proper_seed_order = 0;
 int inplace_partial = 0;
 int do_negotiated_strings = 0;
 int xmit_id0_names = 0;
-int skip_unchanged_negotiated = 0;
 
 struct name_num_item *xattr_sum_nni;
 int xattr_sum_len = 0;
@@ -125,7 +124,6 @@ struct name_num_obj valid_compressions = {
 #define CF_INPLACE_PARTIAL_DIR (1<<6)
 #define CF_VARINT_FLIST_FLAGS (1<<7)
 #define CF_ID0_NAMES (1<<8)
-#define CF_SKIP_UNCHANGED (1<<9)
 
 static const char *client_info;
 
@@ -729,8 +727,6 @@ void setup_protocol(int f_out,int f_in)
 				compat_flags |= CF_INPLACE_PARTIAL_DIR;
 			if (strchr(client_info, 'u') != NULL)
 				compat_flags |= CF_ID0_NAMES;
-			if (strchr(client_info, 'U') != NULL)
-				compat_flags |= CF_SKIP_UNCHANGED;
 			if (strchr(client_info, 'v') != NULL) {
 				do_negotiated_strings = 1;
 				compat_flags |= CF_VARINT_FLIST_FLAGS;
@@ -752,9 +748,6 @@ void setup_protocol(int f_out,int f_in)
 		proper_seed_order = compat_flags & CF_CHKSUM_SEED_FIX ? 1 : 0;
 		xfer_flags_as_varint = compat_flags & CF_VARINT_FLIST_FLAGS ? 1 : 0;
 		xmit_id0_names = compat_flags & CF_ID0_NAMES ? 1 : 0;
-		if (compat_flags & CF_SKIP_UNCHANGED) {
-			skip_unchanged_negotiated = 1;
-		}
 		if (!xfer_flags_as_varint && preserve_crtimes) {
 			fprintf(stderr, "Both rsync versions must be at least 3.2.0 for --crtimes.\n");
 			exit_cleanup(RERR_PROTOCOL);

generator.c

@@ -34,7 +34,6 @@ extern int am_sender;
 extern int am_daemon;
 extern int inc_recurse;
 extern int no_i_r_skip_unchanged;
-extern int skip_unchanged_negotiated;
 extern int relative_paths;
 extern struct stats stats;
 extern int implied_dirs;
@@ -2236,14 +2235,14 @@ void check_for_finished_files(int itemizing, enum logcode code, int check_redo)
 
 /* Pre-scan the file list to mark unchanged files and adjust stats.total_size.
  * This allows accurate progress reporting on resumed transfers. */
-static void prescan_for_unchanged(const char *local_name, int f_out)
+void prescan_for_unchanged(const char *local_name)
 {
 	int i, active_count = 0, skipped_count = 0;
 	char fbuf[MAXPATHLEN];
 	STRUCT_STAT st;
 
-	/* Only prescan if feature was negotiated with remote side */
-	if (!no_i_r_skip_unchanged || !skip_unchanged_negotiated || !cur_flist)
+	/* Only prescan if feature is enabled */
+	if (!no_i_r_skip_unchanged || !cur_flist)
 		return;
 
 	if (DEBUG_GTE(GENR, 1))
@@ -2292,21 +2291,13 @@ static void prescan_for_unchanged(const char *local_name, int f_out)
 		}
 	}
 
-	/* Update stats to reflect skipped files */
+	/* Update stats to reflect only active files for progress display */
 	stats.num_files = active_count;
 	stats.num_skipped_files = skipped_count;
 
 	if (DEBUG_GTE(GENR, 1))
 		rprintf(FINFO, "skipped %d unchanged files, %d active, adjusted size: %.2f GB\n", 
 			skipped_count, active_count, (double)stats.total_size / 1024 / 1024 / 1024);
-	
-	/* Send skipped count and adjusted total_size to sender for accurate progress display */
-	if (f_out >= 0 && skip_unchanged_negotiated) {
-		char buf[12];
-		SIVAL(buf, 0, skipped_count);
-		SIVAL64(buf, 4, stats.total_size);
-		send_msg(MSG_FLIST_COUNT, buf, 12, -1);
-	}
 }
 
 void generate_files(int f_out, const char *local_name)
@@ -2364,13 +2355,7 @@ void generate_files(int f_out, const char *local_name)
 	}
 
 	dflt_perms = (ACCESSPERMS & ~orig_umask);
-
-	/* Pre-scan to mark unchanged files for accurate progress reporting */
-	if (no_i_r_skip_unchanged && !skip_unchanged_negotiated) {
-		rprintf(FWARNING, "WARNING: --no-i-r-skip-unchanged requested but not supported by remote rsync.\n");
-		rprintf(FWARNING, "         Falling back to standard --no-i-r behavior (no progress optimization).\n");
-	}
-	prescan_for_unchanged(local_name, f_out);
+	stats.current_active_index = 0;
 
 	do {
 #ifdef SUPPORT_HARD_LINKS

io.c

@@ -60,7 +60,6 @@ extern int daemon_connection;
 extern int protocol_version;
 extern int remove_source_files;
 extern int preserve_hard_links;
-extern int skip_unchanged_negotiated;
 extern BOOL extra_flist_sending_enabled;
 extern BOOL flush_ok_after_signal;
 extern struct stats stats;
@@ -1513,17 +1512,15 @@ static void read_a_msg(void)
 		iobuf.in_multiplexed = 1;
 		break;
 	case MSG_FLIST_COUNT:
-		if (msg_bytes != 12 || !am_sender || !skip_unchanged_negotiated)
+		if (msg_bytes != 12 || !am_sender)
 			goto invalid_msg;
 		val = raw_read_int();
 		stats.num_skipped_files = val;
-		/* Adjust total file count to reflect only active files */
 		stats.num_files -= val;
-		/* Read and update adjusted total_size for accurate progress percentage */
 		raw_read_buf((char*)&stats.total_size, 8);
 		iobuf.in_multiplexed = 1;
 		if (DEBUG_GTE(IO, 1))
-			rprintf(FINFO, "[%s] received MSG_FLIST_COUNT: %d skipped, %d active, size: %.2f GB\n", 
+			rprintf(FINFO, "[%s] received MSG_FLIST_COUNT: %d skipped, %d active, size: %.2f GB\n",
 				who_am_i(), val, stats.num_files, (double)stats.total_size / 1024 / 1024 / 1024);
 		break;
 	case MSG_REDO:

main.c

@@ -40,6 +40,7 @@ extern int am_server;
 extern int am_sender;
 extern int am_daemon;
 extern int inc_recurse;
+extern int no_i_r_skip_unchanged;
 extern int blocking_io;
 extern int always_checksum;
 extern int remove_source_files;
@@ -1029,6 +1030,18 @@ static int do_recv(int f_in, int f_out, char *local_name)
 
 	io_flush(FULL_FLUSH);
 
+	/* Pre-scan for unchanged files before forking so both processes get updated stats */
+	prescan_for_unchanged(local_name);
+	
+	/* Send adjusted stats to sender for accurate progress (local→remote transfers) */
+	if (no_i_r_skip_unchanged && stats.num_skipped_files > 0) {
+		char buf[12];
+		SIVAL(buf, 0, stats.num_skipped_files);
+		SIVAL64(buf, 4, stats.total_size);
+		send_msg(MSG_FLIST_COUNT, buf, 12, 0);
+		io_flush(NORMAL_FLUSH);
+	}
+
 	if ((pid = do_fork()) == -1) {
 		rsyserr(FERROR, errno, "fork failed in do_recv");
 		exit_cleanup(RERR_IPC);

options.c

@@ -3050,7 +3050,6 @@ int maybe_add_e_option(char *buf, int buf_len)
 		buf[x++] = 'I'; /* support inplace_partial behavior */
 		buf[x++] = 'v'; /* use varint for flist & compat flags; negotiate checksum */
 		buf[x++] = 'u'; /* include name of uid 0 & gid 0 in the id map */
-		buf[x++] = 'U'; /* support --no-i-r-skip-unchanged feature */
 
 		/* NOTE: Avoid using 'V' -- it was represented with the high bit of a write_byte() that became a write_varint(). */
 	}

progress.c

@@ -78,7 +78,7 @@ static void rprint_progress(OFF_T ofs, OFF_T size, struct timeval *now, int is_l
 		int len = snprintf(eol, sizeof eol,
 			" (xfr#%d, %s-chk=%d/%d)\n",
 			stats.xferred_files, flist_eof ? "to" : "ir",
-			stats.num_files - (current_file_index - stats.num_skipped_files) - 1,
+			stats.num_files - stats.current_active_index,
 			stats.num_files);
 		if (INFO_GTE(PROGRESS, 2)) {
 			static int last_len = 0;
@@ -153,6 +153,10 @@ void set_current_file_index(struct file_struct *file, int ndx)
 	else
 		current_file_index = ndx;
 	current_file_index -= cur_flist->flist_num;
+	
+	/* Track active file index for accurate progress with --no-i-r-skip-unchanged */
+	if (file && F_IS_ACTIVE(file))
+		stats.current_active_index++;
 }
 
 void instant_progress(const char *fname)

rsync.h

@@ -269,7 +269,7 @@ enum msgcode {
 	MSG_LOG=FLOG, MSG_CLIENT=FCLIENT, /* sibling logging */
 	MSG_REDO=9,	/* reprocess indicated flist index */
 	MSG_STATS=10,	/* message has stats data for generator */
-	MSG_FLIST_COUNT=11, /* generator sends updated file count to sender */
+	MSG_FLIST_COUNT=11, /* receiver sends adjusted stats to sender after prescan */
 	MSG_IO_ERROR=22,/* the sending side had an I/O error */
 	MSG_IO_TIMEOUT=33,/* tell client about a daemon's timeout value */
 	MSG_NOOP=42,	/* a do-nothing message (legacy protocol-30 only) */
@@ -1046,6 +1046,7 @@ struct stats {
 	int deleted_files, deleted_dirs, deleted_symlinks, deleted_devices, deleted_specials;
 	int xferred_files;
 	int num_skipped_files; /* files marked as unchanged by --no-i-r-skip-unchanged */
+	int current_active_index; /* current index among active files (excluding skipped) */
 };
 
 struct chmod_mode_struct;