Improved the chdir() code:

- Renamed push_dir() to change_dir() and revised it a little so that it
  can chdir() to a relative path without an intervening chdir() back to
  the staring path.
- Renamed push_pathname() to change_pathname() and revised it to take
  different args and to only call path_is_daemon_excluded() on a new
  path (not a revisit of a file's already-checked path).
- Fixed change_pathname() to set the right pathname value when a chdir()
  call fails.
- Set orig_dir once outside of the change_pathname() function.
- Got rid of pop_dir().

clientserver.c

@@ -509,15 +509,15 @@ static int rsync_module(int f_in, int f_out, int i, char *addr, char *host)
 			out_of_memory("rsync_module");
 	}
 
-	/* We do a push_dir() that doesn't actually call chdir()
+	/* We do a change_dir() that doesn't actually call chdir()
 	 * just to make a relative path absolute. */
 	strlcpy(line, curr_dir, sizeof line);
-	if (!push_dir(module_dir, 1))
+	if (!change_dir(module_dir, CD_SKIP_CHDIR))
 		goto chdir_failed;
 	if (strcmp(curr_dir, module_dir) != 0
 	 && (module_dir = strdup(curr_dir)) == NULL)
 		out_of_memory("rsync_module");
-	push_dir(line, 1); /* Restore curr_dir. */
+	change_dir(line, CD_SKIP_CHDIR); /* Restore curr_dir. */
 
 	if (use_chroot) {
 		chroot_path = module_dir;
@@ -673,12 +673,12 @@ static int rsync_module(int f_in, int f_out, int i, char *addr, char *host)
 			io_printf(f_out, "@ERROR: chroot failed\n");
 			return -1;
 		}
-		if (!push_dir(module_dir, 0))
+		if (!change_dir(module_dir, CD_NORMAL))
 			goto chdir_failed;
 		if (module_dirlen)
 			sanitize_paths = 1;
 	} else {
-		if (!push_dir(module_dir, 0)) {
+		if (!change_dir(module_dir, CD_NORMAL)) {
 		  chdir_failed:
 			rsyserr(FLOG, errno, "chdir %s failed\n", module_dir);
 			io_printf(f_out, "@ERROR: chdir failed\n");

flist.c

@@ -242,10 +242,10 @@ static inline int is_daemon_excluded(const char *fname, int is_dir)
 	return 0;
 }
 
-static inline int path_is_daemon_excluded(const char *path, int ignore_filename)
+static inline int path_is_daemon_excluded(char *path, int ignore_filename)
 {
 	if (daemon_filter_list.head) {
-		char *slash = (char*)path;
+		char *slash = path;
 
 		while ((slash = strchr(slash+1, '/')) != NULL) {
 			int ret;
@@ -293,7 +293,6 @@ static void send_directory(int f, struct file_list *flist,
 static const char *pathname, *orig_dir;
 static int pathname_len;
 
-
 /* Make sure flist can hold at least flist->used + extra entries. */
 static void flist_expand(struct file_list *flist, int extra)
 {
@@ -339,28 +338,46 @@ static void flist_done_allocating(struct file_list *flist)
 		flist->pool_boundary = ptr;
 }
 
-int push_pathname(const char *dir, int len)
+/* Call this with EITHER (1) "file, NULL, 0" to chdir() to the file's
+ * F_PATHNAME(), or (2) "NULL, dir, dirlen" to chdir() to the supplied dir,
+ * with dir == NULL taken to be the starting directory, and dirlen < 0
+ * indicating that strdup(dir) should be called and then the -dirlen length
+ * value checked to ensure that it is not daemon-excluded. */
+int change_pathname(struct file_struct *file, const char *dir, int dirlen)
 {
-	if (dir == pathname)
-		return 1;
-
-	if (!orig_dir)
-		orig_dir = strdup(curr_dir);
-
-	if (pathname && !pop_dir(orig_dir)) {
-		rsyserr(FERROR, errno, "pop_dir %s failed",
-			full_fname(orig_dir));
-		exit_cleanup(RERR_FILESELECT);
+	if (dirlen < 0) {
+		char *cpy = strdup(dir);
+		if (*cpy != '/')
+			change_dir(orig_dir, CD_SKIP_CHDIR);
+		if (path_is_daemon_excluded(cpy, 0))
+			goto chdir_error;
+		dir = cpy;
+		dirlen = -dirlen;
+	} else {
+		if (file) {
+			if (pathname == F_PATHNAME(file))
+				return 1;
+			dir = F_PATHNAME(file);
+			if (dir)
+				dirlen = strlen(dir);
+		} else if (pathname == dir)
+			return 1;
+		if (dir && *dir != '/')
+			change_dir(orig_dir, CD_SKIP_CHDIR);
 	}
 
-	if (dir && (path_is_daemon_excluded(dir, 0) || !push_dir(dir, 0))) {
+	if (!change_dir(dir ? dir : orig_dir, CD_NORMAL)) {
+	  chdir_error:
 		io_error |= IOERR_GENERAL;
-		rsyserr(FERROR, errno, "push_dir %s failed", full_fname(dir));
+		rsyserr(FERROR, errno, "change_dir %s failed", full_fname(dir));
+		change_dir(orig_dir, CD_NORMAL);
+		pathname = NULL;
+		pathname_len = 0;
 		return 0;
 	}
 
 	pathname = dir;
-	pathname_len = len >= 0 ? len : dir ? (int)strlen(dir) : 0;
+	pathname_len = dirlen;
 
 	return 1;
 }
@@ -1666,10 +1683,8 @@ static void send1extra(int f, struct file_struct *file, struct file_list *flist)
 	f_name(file, fbuf);
 	dlen = strlen(fbuf);
 
-	if (F_PATHNAME(file) != pathname) {
-		if (!push_pathname(F_PATHNAME(file), -1))
-			exit_cleanup(RERR_FILESELECT);
-	}
+	if (!change_pathname(file, NULL, 0))
+		exit_cleanup(RERR_FILESELECT);
 
 	change_local_filter_dir(fbuf, dlen, send_dir_depth);
 
@@ -1852,6 +1867,9 @@ struct file_list *send_file_list(int f, int argc, char *argv[])
 	start_write = stats.total_written;
 	gettimeofday(&start_tv, NULL);
 
+	if (!orig_dir)
+		orig_dir = strdup(curr_dir);
+
 	if (relative_paths && protocol_version >= 30)
 		implied_dirs = 1; /* We send flagged implied dirs */
 
@@ -1869,8 +1887,8 @@ struct file_list *send_file_list(int f, int argc, char *argv[])
 
 	disable_buffering = io_start_buffering_out(f);
 	if (filesfrom_fd >= 0) {
-		if (argv[0] && !push_dir(argv[0], 0)) {
-			rsyserr(FERROR_XFER, errno, "push_dir %s failed",
+		if (argv[0] && !change_dir(argv[0], CD_NORMAL)) {
+			rsyserr(FERROR_XFER, errno, "change_dir %s failed",
 				full_fname(argv[0]));
 			exit_cleanup(RERR_FILESELECT);
 		}
@@ -1994,11 +2012,11 @@ struct file_list *send_file_list(int f, int argc, char *argv[])
 
 		dirlen = dir ? strlen(dir) : 0;
 		if (dirlen != lastdir_len || memcmp(lastdir, dir, dirlen) != 0) {
-			if (!push_pathname(dir ? strdup(dir) : NULL, dirlen))
+			if (!change_pathname(NULL, dir, -dirlen))
 				continue;
 			lastdir = pathname;
 			lastdir_len = pathname_len;
-		} else if (!push_pathname(lastdir, lastdir_len))
+		} else if (!change_pathname(NULL, lastdir, lastdir_len))
 			continue;
 
 		if (fn != fbuf)

main.c

@@ -519,8 +519,8 @@ static char *get_local_name(struct file_list *flist, char *dest_path)
 	if ((statret = do_stat(dest_path, &st)) == 0) {
 		/* If the destination is a dir, enter it and use mode 1. */
 		if (S_ISDIR(st.st_mode)) {
-			if (!push_dir(dest_path, 0)) {
-				rsyserr(FERROR, errno, "push_dir#1 %s failed",
+			if (!change_dir(dest_path, CD_NORMAL)) {
+				rsyserr(FERROR, errno, "change_dir#1 %s failed",
 					full_fname(dest_path));
 				exit_cleanup(RERR_FILESELECT);
 			}
@@ -579,8 +579,8 @@ static char *get_local_name(struct file_list *flist, char *dest_path)
 			dry_run++;
 		}
 
-		if (!push_dir(dest_path, dry_run > 1)) {
-			rsyserr(FERROR, errno, "push_dir#2 %s failed",
+		if (!change_dir(dest_path, dry_run > 1 ? CD_SKIP_CHDIR : CD_NORMAL)) {
+			rsyserr(FERROR, errno, "change_dir#2 %s failed",
 				full_fname(dest_path));
 			exit_cleanup(RERR_FILESELECT);
 		}
@@ -599,8 +599,8 @@ static char *get_local_name(struct file_list *flist, char *dest_path)
 		dest_path = "/";
 
 	*cp = '\0';
-	if (!push_dir(dest_path, 0)) {
-		rsyserr(FERROR, errno, "push_dir#3 %s failed",
+	if (!change_dir(dest_path, CD_NORMAL)) {
+		rsyserr(FERROR, errno, "change_dir#3 %s failed",
 			full_fname(dest_path));
 		exit_cleanup(RERR_FILESELECT);
 	}
@@ -692,8 +692,8 @@ static void do_server_sender(int f_in, int f_out, int argc, char *argv[])
 	}
 
 	if (!relative_paths) {
-		if (!push_dir(dir, 0)) {
-			rsyserr(FERROR, errno, "push_dir#3 %s failed",
+		if (!change_dir(dir, CD_NORMAL)) {
+			rsyserr(FERROR, errno, "change_dir#3 %s failed",
 				full_fname(dir));
 			exit_cleanup(RERR_FILESELECT);
 		}
@@ -862,8 +862,8 @@ static void do_server_recv(int f_in, int f_out, int argc, char *argv[])
 		char *dir = argv[0];
 		argc--;
 		argv++;
-		if (!am_daemon && !push_dir(dir, 0)) {
-			rsyserr(FERROR, errno, "push_dir#4 %s failed",
+		if (!am_daemon && !change_dir(dir, CD_NORMAL)) {
+			rsyserr(FERROR, errno, "change_dir#4 %s failed",
 				full_fname(dir));
 			exit_cleanup(RERR_FILESELECT);
 		}
@@ -1428,11 +1428,11 @@ int main(int argc,char *argv[])
 	SIGACTION(SIGXFSZ, SIG_IGN);
 #endif
 
-	/* Initialize push_dir here because on some old systems getcwd
+	/* Initialize change_dir() here because on some old systems getcwd
 	 * (implemented by forking "pwd" and reading its output) doesn't
 	 * work when there are other child processes.  Also, on all systems
 	 * that implement getcwd that way "pwd" can't be found after chroot. */
-	push_dir(NULL, 0);
+	change_dir(NULL, CD_NORMAL);
 
 	init_flist();
 
@@ -1456,7 +1456,6 @@ int main(int argc,char *argv[])
 			read_stream_flags(batch_fd);
 		else
 			write_stream_flags(batch_fd);
-
 	}
 	if (write_batch < 0)
 		dry_run = 1;

rsync.h

@@ -199,6 +199,9 @@
 #define SP_DEFAULT 0
 #define SP_KEEP_DOT_DIRS (1<<0)
 
+#define CD_NORMAL 0
+#define CD_SKIP_CHDIR 1
+
 /* Log-message categories.  FLOG only goes to the log file, not the client;
  * FCLIENT is the opposite. */
 enum logcode {

sender.c

@@ -135,7 +135,7 @@ void successful_send(int ndx)
 	}
 
 	file = flist->files[ndx - flist->ndx_start];
-	if (!push_pathname(F_PATHNAME(file), -1))
+	if (!change_pathname(file, NULL, 0))
 		return;
 	f_name(file, fname);
 
@@ -221,7 +221,7 @@ void send_files(int f_in, int f_out)
 		} else {
 			path = slash = "";
 		}
-		if (!push_pathname(F_PATHNAME(file), -1))
+		if (!change_pathname(file, NULL, 0))
 			continue;
 		f_name(file, fname);
 

util.c

@@ -943,7 +943,7 @@ char *sanitize_path(char *dest, const char *p, const char *rootdir, int depth,
 /* Like chdir(), but it keeps track of the current directory (in the
  * global "curr_dir"), and ensures that the path size doesn't overflow.
  * Also cleans the path using the clean_fname() function. */
-int push_dir(const char *dir, int set_path_only)
+int change_dir(const char *dir, int set_path_only)
 {
 	static int initialised;
 	unsigned int len;
@@ -961,21 +961,26 @@ int push_dir(const char *dir, int set_path_only)
 	if (len == 1 && *dir == '.')
 		return 1;
 
-	if ((*dir == '/' ? len : curr_dir_len + 1 + len) >= sizeof curr_dir) {
-		errno = ENAMETOOLONG;
-		return 0;
-	}
-
-	if (!set_path_only && chdir(dir))
-		return 0;
-
 	if (*dir == '/') {
+		if (len >= sizeof curr_dir) {
+			errno = ENAMETOOLONG;
+			return 0;
+		}
+		if (!set_path_only && chdir(dir))
+			return 0;
 		memcpy(curr_dir, dir, len + 1);
-		curr_dir_len = len;
 	} else {
-		curr_dir[curr_dir_len++] = '/';
-		memcpy(curr_dir + curr_dir_len, dir, len + 1);
-		curr_dir_len += len;
+		if (curr_dir_len + 1 + len >= sizeof curr_dir) {
+			errno = ENAMETOOLONG;
+			return 0;
+		}
+		curr_dir[curr_dir_len] = '/';
+		memcpy(curr_dir + curr_dir_len + 1, dir, len + 1);
+
+		if (!set_path_only && chdir(curr_dir)) {
+			curr_dir[curr_dir_len] = '\0';
+			return 0;
+		}
 	}
 
 	curr_dir_len = clean_fname(curr_dir, CFN_COLLAPSE_DOT_DOT_DIRS);
@@ -986,28 +991,7 @@ int push_dir(const char *dir, int set_path_only)
 	}
 
 	if (verbose >= 5 && !set_path_only)
-		rprintf(FINFO, "[%s] push_dir(%s)\n", who_am_i(), curr_dir);
-
-	return 1;
-}
-
-/**
- * Reverse a push_dir() call.  You must pass in an absolute path
- * that was copied from a prior value of "curr_dir".
- **/
-int pop_dir(const char *dir)
-{
-	if (chdir(dir))
-		return 0;
-
-	curr_dir_len = strlcpy(curr_dir, dir, sizeof curr_dir);
-	if (curr_dir_len >= sizeof curr_dir)
-		curr_dir_len = sizeof curr_dir - 1;
-	if (sanitize_paths)
-		curr_dir_depth = count_dir_elements(curr_dir + module_dirlen);
-
-	if (verbose >= 5)
-		rprintf(FINFO, "[%s] pop_dir(%s)\n", who_am_i(), curr_dir);
+		rprintf(FINFO, "[%s] change_dir(%s)\n", who_am_i(), curr_dir);
 
 	return 1;
 }