Simplify the compat logic for local_server

Change the logic in compat.c to construct the client_info string value for a local copy so that the various checks of the string don't need to make an exception for local_server.
2026-05-19 12:25:42 -04:00 · 2020-08-27 18:58:21 -07:00
parent c3f7414c45
commit 25526eb3fe
2 changed files with 65 additions and 52 deletions
--- a/compat.c
+++ b/compat.c
@@ -21,6 +21,7 @@

 #include "rsync.h"
 #include "itypes.h"
+#include "ifuncs.h"

 extern int am_server;
 extern int am_sender;
@@ -153,7 +154,13 @@ static void check_sub_protocol(void)

 void set_allow_inc_recurse(void)
 {
-	client_info = shell_cmd ? shell_cmd : "";
+	if (!local_server)
+		client_info = shell_cmd ? shell_cmd : "";
+	else if (am_server) {
+		char buf[64];
+		maybe_add_e_option(buf, sizeof buf);
+		client_info = *buf ? strdup(buf+1) : ""; /* The +1 skips the leading "e". */
+	}

 	if (!recurse || use_qsort)
 		allow_inc_recurse = 0;
@@ -161,8 +168,7 @@ void set_allow_inc_recurse(void)
 	 && (delete_before || delete_after
 	  || delay_updates || prune_empty_dirs))
 		allow_inc_recurse = 0;
-	else if (am_server && !local_server
-	 && (strchr(client_info, 'i') == NULL))
+	else if (am_server && strchr(client_info, 'i') == NULL)
 		allow_inc_recurse = 0;
 }

@@ -558,7 +564,7 @@ void setup_protocol(int f_out,int f_in)
 		atimes_ndx = (file_extra_cnt += EXTRA64_CNT);
 	if (preserve_crtimes)
 		crtimes_ndx = (file_extra_cnt += EXTRA64_CNT);
-	if (am_sender) /* This is most likely in the in64 union as well. */
+	if (am_sender) /* This is most likely in the file_extras64 union as well. */
 		pathname_ndx = (file_extra_cnt += PTR_EXTRA_CNT);
 	else
 		depth_ndx = ++file_extra_cnt;
@@ -691,17 +697,17 @@ void setup_protocol(int f_out,int f_in)
 #ifdef ICONV_OPTION
 			compat_flags |= CF_SYMLINK_ICONV;
 #endif
-			if (local_server || strchr(client_info, 'f') != NULL)
+			if (strchr(client_info, 'f') != NULL)
 				compat_flags |= CF_SAFE_FLIST;
-			if (local_server || strchr(client_info, 'x') != NULL)
+			if (strchr(client_info, 'x') != NULL)
 				compat_flags |= CF_AVOID_XATTR_OPTIM;
-			if (local_server || strchr(client_info, 'C') != NULL)
+			if (strchr(client_info, 'C') != NULL)
 				compat_flags |= CF_CHKSUM_SEED_FIX;
-			if (local_server || strchr(client_info, 'I') != NULL)
+			if (strchr(client_info, 'I') != NULL)
 				compat_flags |= CF_INPLACE_PARTIAL_DIR;
-			if (local_server || strchr(client_info, 'u') != NULL)
+			if (strchr(client_info, 'u') != NULL)
 				compat_flags |= CF_ID0_NAMES;
-			if (local_server || strchr(client_info, 'v') != NULL) {
+			if (strchr(client_info, 'v') != NULL) {
 				do_negotiated_strings = 1;
 				compat_flags |= CF_VARINT_FLIST_FLAGS;
 			}
@@ -737,7 +743,7 @@ void setup_protocol(int f_out,int f_in)
 #endif
 #ifdef ICONV_OPTION
 		sender_symlink_iconv = iconv_opt && (am_server
-		    ? local_server || strchr(client_info, 's') != NULL
+		    ? strchr(client_info, 's') != NULL
 		    : !!(compat_flags & CF_SYMLINK_ICONV));
 #endif
 		if (inc_recurse && !allow_inc_recurse) {
--- a/options.c
+++ b/options.c
@@ -2577,47 +2577,8 @@ void server_options(char **args, int *argc_p)

 	set_allow_inc_recurse();

-	/* We don't really know the actual protocol_version at this point,
-	 * but checking the pre-negotiated value allows the user to use a
-	 * --protocol=29 override to avoid the use of this -eFLAGS opt. */
-	if (protocol_version >= 30) {
-		/* Use "eFlags" alias so that cull_options doesn't think that these are no-arg option letters. */
-#define eFlags argstr
-		/* We make use of the -e option to let the server know about
-		 * any pre-release protocol version && some behavior flags. */
-		eFlags[x++] = 'e';
-#if SUBPROTOCOL_VERSION != 0
-		if (protocol_version == PROTOCOL_VERSION) {
-			x += snprintf(argstr+x, sizeof argstr - x,
-				      "%d.%d",
-				      PROTOCOL_VERSION, SUBPROTOCOL_VERSION);
-		} else
-#endif
-			eFlags[x++] = '.';
-		if (allow_inc_recurse)
-			eFlags[x++] = 'i';
-#ifdef CAN_SET_SYMLINK_TIMES
-		eFlags[x++] = 'L'; /* symlink time-setting support */
-#endif
-#ifdef ICONV_OPTION
-		eFlags[x++] = 's'; /* symlink iconv translation support */
-#endif
-		eFlags[x++] = 'f'; /* flist I/O-error safety support */
-		eFlags[x++] = 'x'; /* xattr hardlink optimization not desired */
-		eFlags[x++] = 'C'; /* support checksum seed order fix */
-		eFlags[x++] = 'I'; /* support inplace_partial behavior */
-		eFlags[x++] = 'v'; /* use varint for flist & compat flags; negotiate checksum */
-		eFlags[x++] = 'u'; /* include name of uid 0 & gid 0 in the id map */
-		/* NOTE: Avoid using 'V' -- it was the high bit of a write_byte() that became write_varint(). */
-#undef eFlags
-	}
-
-	if (x >= (int)sizeof argstr) { /* Not possible... */
-		rprintf(FERROR, "argstr overflow in server_options().\n");
-		exit_cleanup(RERR_MALLOC);
-	}
-
-	argstr[x] = '\0';
+	/* This '\0'-terminates argstr and makes sure it didn't overflow. */
+	x += maybe_add_e_option(argstr + x, (int)sizeof argstr - x);

 	if (x > 1)
 		args[ac++] = argstr;
@@ -2926,6 +2887,52 @@ void server_options(char **args, int *argc_p)
 	out_of_memory("server_options");
 }

+int maybe_add_e_option(char *buf, int buf_len)
+{
+	int x = 0;
+
+	/* We don't really know the actual protocol_version at this point,
+	 * but checking the pre-negotiated value allows the user to use a
+	 * --protocol=29 override to avoid the use of this -eFLAGS opt. */
+	if (protocol_version >= 30 && buf_len > 0) {
+		/* We make use of the -e option to let the server know about
+		 * any pre-release protocol version && some behavior flags. */
+		buf[x++] = 'e';
+
+#if SUBPROTOCOL_VERSION != 0
+		if (protocol_version == PROTOCOL_VERSION)
+			x += snprintf(buf + x, buf_len - x, "%d.%d", PROTOCOL_VERSION, SUBPROTOCOL_VERSION);
+		else
+#endif
+			buf[x++] = '.';
+		if (allow_inc_recurse)
+			buf[x++] = 'i';
+#ifdef CAN_SET_SYMLINK_TIMES
+		buf[x++] = 'L'; /* symlink time-setting support */
+#endif
+#ifdef ICONV_OPTION
+		buf[x++] = 's'; /* symlink iconv translation support */
+#endif
+		buf[x++] = 'f'; /* flist I/O-error safety support */
+		buf[x++] = 'x'; /* xattr hardlink optimization not desired */
+		buf[x++] = 'C'; /* support checksum seed order fix */
+		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 */
+
+		/* NOTE: Avoid using 'V' -- it was represented with the high bit of a write_byte() that became a write_varint(). */
+	}
+
+	if (x >= buf_len) { /* Not possible... */
+		rprintf(FERROR, "overflow in add_e_flags().\n");
+		exit_cleanup(RERR_MALLOC);
+	}
+
+	buf[x] = '\0';
+
+	return x;
+}
+
 /* If str points to a valid hostspec, return allocated memory containing the
 * [USER@]HOST part of the string, and set the path_start_ptr to the part of
 * the string after the host part.  Otherwise, return NULL.  If port_ptr is