X-Git-Url: https://git.sesse.net/?p=betaftpd;a=blobdiff_plain;f=cmds.c;h=2e38823ab9d4716ae5c2f6aae5805e513c819fca;hp=c17fef9508dfe79c25ec6340ba781fdd7326e82c;hb=HEAD;hpb=e782726047aa73c6dc592981d75ea21e1adf3d3d

diff --git a/cmds.c b/cmds.c
index c17fef9..2e38823 100644
--- a/cmds.c
+++ b/cmds.c
@@ -149,7 +149,7 @@ extern fd_set master_fds, master_send_fds;
 struct handler {
 	char cmd_name[6];
 	char add_cmlen;		/* =1 if the command takes an argument */
-	int (*callback)(struct conn * const);
+	void (*callback)(struct conn * const);
 	char min_auth;
 #if !WANT_NONROOT
 	char do_setuid;		/* =1 if root is not *really* needed */
@@ -263,7 +263,7 @@ int do_chdir(struct conn * const c, const char * const newd)
  *		authentication work. User names are limited to 16
  *		characters, by force...
  */
-int cmd_user(struct conn * const c)
+void cmd_user(struct conn * const c)
 {
 	strncpy(c->username, c->recv_buf, 16);
 	c->username[16] = 0;
@@ -278,7 +278,6 @@ int cmd_user(struct conn * const c)
 		numeric(c, 331, "Password required for %s.", c->username);
 		c->auth = 2;
 	}
-	return 1;
 }
 
 /*
@@ -289,7 +288,7 @@ int cmd_user(struct conn * const c)
  *		don't even support PAM or real shadow passwords (with
  *		expiry etc) yet...
  */
-int cmd_pass(struct conn * const c)
+void cmd_pass(struct conn * const c)
 {
 #if WANT_NONROOT
 	c->auth = nr_userinfo(c->username, &c->uid, c->curr_dir, c->root_dir,
@@ -329,7 +328,7 @@ int cmd_pass(struct conn * const c)
 		) {
 			c->auth = 0;
 		} else {
-			c->auth = 3;
+			c->auth = 4;
 		}
 	}
 #endif /* !WANT_NONROOT */
@@ -345,9 +344,9 @@ int cmd_pass(struct conn * const c)
 		chdir(c->curr_dir);
 		dump_file(c, 230, "welcome.msg");
 #endif
+		/* Have a different message for anonymous users? */
 		numeric(c, 230, "User logged in.");
 	}
-	return 1;
 }
 
 /*
@@ -361,10 +360,9 @@ int cmd_pass(struct conn * const c)
  *		I feel that the RFC959 intention is having it _before_
  *		USER/PASS. Therefore, this one runs with root privilegies :-)
  */
-int cmd_acct(struct conn * const c)
+void cmd_acct(struct conn * const c)
 {
 	numeric(c, 202, "ACCT ignored OK -- not applicable on this system.");
-	return 1;
 }
 
 /*
@@ -374,7 +372,7 @@ int cmd_acct(struct conn * const c)
  *		the whole way), in case there are some weird overflows
  * 		somewhere.
  */
-int cmd_port(struct conn * const c)
+void cmd_port(struct conn * const c)
 {
 	short int a0, a1, a2, a3, p0, p1;
 	int i, sock, err;
@@ -383,11 +381,11 @@ int cmd_port(struct conn * const c)
     
 	if ((c->transfer != NULL) && (c->transfer->state >= 4)) {
 		numeric(c, 500, "Sorry, only one transfer at a time.");
-		return 1;
+		return;
 	}
 
 	sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
-	TRAP_ERROR(sock == -1, 500, return 1);
+	TRAP_ERROR(sock == -1, 500, return);
 
 	destroy_ftran(c->transfer);
 	c->transfer = f = alloc_new_ftran(sock, c);
@@ -402,7 +400,7 @@ int cmd_port(struct conn * const c)
 		/* bind to own address, port 20 (FTP data) */
 		tmp = sizeof(sin);
 		err = getsockname(c->sock, (struct sockaddr *)&sin, &tmp);
-		TRAP_ERROR(err == -1, 500, return 1);
+		TRAP_ERROR(err == -1, 500, return);
 		sin.sin_port = FTP_PORT - 1;
 
 		numeric(c, 200, "PORT command OK.");
@@ -415,8 +413,8 @@ int cmd_port(struct conn * const c)
 #endif
 		bind(sock, (struct sockaddr *)&sin, sizeof(sin));
 #if !WANT_NONROOT
-		seteuid(c->uid);
 		setegid(c->gid);
+		seteuid(c->uid);
 #endif
 
 		f->sin.sin_family = AF_INET;
@@ -434,14 +432,13 @@ int cmd_port(struct conn * const c)
 		i = 1;		
 		ioctl(f->sock, FIONBIO, &one);
 	}
-	return 1;
 }
 
 /*
  * cmd_pasv():	Handles the PASV command, and sets up the data socket.
  *		Uses port numbers > 1024, since it doesn't run as root.
  */
-int cmd_pasv(struct conn * const c)
+void cmd_pasv(struct conn * const c)
 {
 	struct ftran *f;
 	int tmp, sock, err;
@@ -450,14 +447,14 @@ int cmd_pasv(struct conn * const c)
 
 	if ((c->transfer != NULL) && (c->transfer->state >= 4)) {
 		numeric(c, 503, "Sorry, only one transfer at once.");
-		return 1;
+		return;
 	}
 	destroy_ftran(c->transfer);
 
 	sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
-	TRAP_ERROR(sock == -1, 500, return 1);
+	TRAP_ERROR(sock == -1, 500, return);
 	err = add_fd(sock, POLLIN);
-	TRAP_ERROR(err != 0, 501, return 1);
+	TRAP_ERROR(err != 0, 501, return);
 
 	c->transfer = f = alloc_new_ftran(sock, c);
 
@@ -466,18 +463,18 @@ int cmd_pasv(struct conn * const c)
 	/* setup socket */
 	tmp = sizeof(addr);
 	err = getsockname(c->sock, (struct sockaddr *)&addr, &tmp);
-	TRAP_ERROR(err == -1, 500, return 1);
+	TRAP_ERROR(err == -1, 500, return);
 
 	addr.sin_port = 0;	/* let the system choose */
 	err = bind(sock, (struct sockaddr *)&addr, sizeof(struct sockaddr));
-	TRAP_ERROR(err == -1, 500, return 1);
+	TRAP_ERROR(err == -1, 500, return);
 
 	tmp = sizeof(addr);
 	err = getsockname(sock, (struct sockaddr *)&addr, &tmp);
-	TRAP_ERROR(err == -1, 500, return 1);
+	TRAP_ERROR(err == -1, 500, return);
 
 	err = listen(f->sock, 1);
-	TRAP_ERROR(err == -1, 500, return 1);
+	TRAP_ERROR(err == -1, 500, return);
 	f->state = 1;
 
 	numeric(c, 227, "Entering passive mode (%u,%u,%u,%u,%u,%u)",
@@ -487,7 +484,6 @@ int cmd_pasv(struct conn * const c)
 		(htonl(addr.sin_addr.s_addr) & 0x000000ff),
 		(htons(addr.sin_port) & 0xff00) >> 8,
 		(htons(addr.sin_port) & 0x00ff));
-	return 1;
 }
 
 /*
@@ -498,7 +494,7 @@ int cmd_pasv(struct conn * const c)
  *		/betaftpd.users file, if you use nonroot. If not, it's a bug.
  *		Try to get it _reproducible_, and mail it to me.
  */
-int cmd_pwd(struct conn * const c)
+void cmd_pwd(struct conn * const c)
 {
 	char temp[512], *cdir = NULL;
 
@@ -506,7 +502,6 @@ int cmd_pwd(struct conn * const c)
 	if (cdir != NULL) {
 		numeric(c, 257, "\"%s\" is current working directory.", cdir);
 	}
-	return 1;
 }
 
 /*
@@ -521,6 +516,7 @@ char *do_pwd(struct conn * const c, char * const retbuf, const char * const dir)
 	char *cdir = NULL;
 
 	strcpy(retbuf, dir);
+
 	if (strncmp(retbuf, c->root_dir, strlen(c->root_dir)) != 0) {
 		numeric(c, 550, "curr_dir is outside root_dir, please contact site administrator.");
 		return NULL;
@@ -540,10 +536,9 @@ char *do_pwd(struct conn * const c, char * const retbuf, const char * const dir)
  * cmd_cwd():	Handles CWD command (change working directory). Uses
  *		cmd_cwd_internal() (see below).
  */
-int cmd_cwd(struct conn * const c)
+void cmd_cwd(struct conn * const c)
 {
 	cmd_cwd_internal(c, c->recv_buf);
-	return 1;
 }
 
 /*
@@ -556,10 +551,9 @@ int cmd_cwd(struct conn * const c)
  *		an error, instead of just staying in the root directory (as
  *		the OS and thus wu-ftpd does).
  */
-int cmd_cdup(struct conn * const c)
+void cmd_cdup(struct conn * const c)
 {
 	cmd_cwd_internal(c, "..");
-	return 1;
 }
 
 /*
@@ -594,11 +588,10 @@ void cmd_cwd_internal(struct conn * const c, const char * const newd)
  *		sending functions to start at the correct number. We should
  *		perhaps add some better error checking to this?
  */
-int cmd_rest(struct conn * const c)
+void cmd_rest(struct conn * const c)
 {
 	c->rest_pos = abs(atoi(c->recv_buf));
 	numeric(c, 350, "Setting resume at %u bytes.", c->rest_pos);
-	return 1;
 }
 
 /*
@@ -608,19 +601,19 @@ int cmd_rest(struct conn * const c)
  *		connection occurs (or succeeds, if we're using PORT mode),
  *		the actual file transfer begins.
  */
-int cmd_retr(struct conn * const c)
+void cmd_retr(struct conn * const c)
 {
 	struct ftran *f = c->transfer;
 
 	if ((f == NULL) || ((f->state != 1) && (f->state != 3))) {
 		numeric(c, 425, "No data connection set up; please use PASV or PORT.");
-		return 1;
+		return;
 	}
 
 #if WANT_ASCII
 	if ((c->rest_pos > 0) && (c->ascii_mode == 1)) {
 		numeric(c, 500, "Cannot resume while in ASCII mode.");
-		return 1;
+		return;
 	}
 #endif
 
@@ -643,7 +636,6 @@ int cmd_retr(struct conn * const c)
 #endif
 		prepare_for_transfer(f);
 	}
-	return 1;
 }
 
 #if WANT_UPLOAD
@@ -651,20 +643,18 @@ int cmd_retr(struct conn * const c)
  * cmd_stor():	Handles the STOR command (upload file). Pushes the
  *		work down to do_store(), below.
  */
-int cmd_stor(struct conn * const c)
+void cmd_stor(struct conn * const c)
 {
 	do_store(c, 0);
-	return 1;
 }
 
 /*
  * cmd_appe():	Handles the APPE command (append to file). Pushes
  *		the work down to do_store(), below.
  */
-int cmd_appe(struct conn * const c)
+void cmd_appe(struct conn * const c)
 {
 	do_store(c, 1);
-	return 1;
 }
 
 /*
@@ -721,22 +711,21 @@ void do_store(struct conn * const c, const int append)
  *		size of all the files in the directory, rather how
  *		much space the directory inode uses.
  */
-int cmd_size(struct conn * const c)
+void cmd_size(struct conn * const c)
 {
 #if WANT_ASCII
 	if (c->ascii_mode) {
 		numeric(c, 550, "SIZE not available in ASCII mode.");
-		return 1;
+		return;
 	}
 #endif
 	{
 		const char * const fname = translate_path(c, c->recv_buf);
 		struct stat buf;
 	
-		TRAP_ERROR(fname == NULL || lstat(fname, &buf) == -1, 550, return 1);
+		TRAP_ERROR(fname == NULL || lstat(fname, &buf) == -1, 550, return);
 	
 		numeric(c, 213, "%lu", (unsigned long)(buf.st_size));
-		return 1;
 	}
 }
 
@@ -745,86 +734,81 @@ int cmd_size(struct conn * const c)
  *		date/time of a file. See the comments on cmd_size(),
  *		above.
  */
-int cmd_mdtm(struct conn * const c)
+void cmd_mdtm(struct conn * const c)
 {
 	const char * const fname = translate_path(c, c->recv_buf);
 	struct stat buf;
 	struct tm *m;
 
-	TRAP_ERROR(fname == NULL || lstat(fname, &buf) == -1, 550, return 1);
+	TRAP_ERROR(fname == NULL || lstat(fname, &buf) == -1, 550, return);
 
 	m = gmtime(&(buf.st_mtime));	/* at least wu-ftpd does it in GMT */
 	numeric(c, 213, "%u%02u%02u%02u%02u%02u", m->tm_year + 1900,
 		m->tm_mon + 1, m->tm_mday, m->tm_hour, m->tm_min, m->tm_sec);
-	return 1;
 }
 
 /*
  * cmd_abor():	Handle the ABOR command (abort a file transfer). This should
  *		be clean enough, but isn't tested extensively.
  */
-int cmd_abor(struct conn * const c)
+void cmd_abor(struct conn * const c)
 {
 	if (c->transfer != NULL) {
 		numeric(c, 426, "File transfer aborted.");
 		destroy_ftran(c->transfer);
 	}
 	numeric(c, 226, "ABOR command processed OK.");
-	return 1;
 }
 
 /*
  * cmd_dele():	Handle the DELE command (delete a file).
  */
-int cmd_dele(struct conn * const c)
+void cmd_dele(struct conn * const c)
 {
 	const char * const fname = translate_path(c, c->recv_buf);
 	
-	TRAP_ERROR(fname == NULL || unlink(fname) == -1, 550, return 1);
+	TRAP_ERROR(fname == NULL || unlink(fname) == -1, 550, return);
 	numeric(c, 250, "File deleted OK.");
-	return 1;
 }
 
 /*
  * cmd_rnfr():	Handle the RNFR command (take a filename to rename from).
  */
-int cmd_rnfr(struct conn * const c)
+void cmd_rnfr(struct conn * const c)
 {
 	const char * const fname = translate_path(c, c->recv_buf);
 	char cwd[256];
 	struct stat buf;
 
 	c->rename_from[0] = '\0';
-	if (fname == NULL) return 1;
+	if (fname == NULL) return;
 	
 	getcwd(cwd, 256);
 	snprintf(c->rename_from, 256, "%s/%s", cwd, fname);
 
 	/* Just check that the file exists. */
-	TRAP_ERROR(lstat(c->rename_from, &buf) == -1, 550, c->rename_from[0] = '\0'; return 1);
+	TRAP_ERROR(lstat(c->rename_from, &buf) == -1, 550, c->rename_from[0] = '\0'; return);
 
 	numeric(c, 350, "File exists, send RNTO.");
-	return 1;
 }
 
 /*
  * cmd_rnto():	Handle the RNTO command (do the actual renaming).
  */
-int cmd_rnto(struct conn * const c)
+void cmd_rnto(struct conn * const c)
 {
 	const char * const fname = translate_path(c, c->recv_buf);
 
-	if (fname == NULL) return 1;
+	if (fname == NULL) return;
 	if (c->rename_from[0] == '\0') {
 		numeric(c, 503, "Please send RNFR first.");
-		return 1;
+		return;
 	}
 
-	TRAP_ERROR(rename(c->rename_from, fname) == -1, 550, c->rename_from[0] = '\0'; return 1);
+	TRAP_ERROR(rename(c->rename_from, fname) == -1, 550, c->rename_from[0] = '\0'; return);
 	c->rename_from[0] = '\0';
 
 	numeric(c, 250, "File renamed successfully.");
-	return 1;
 }
 
 /*
@@ -841,18 +825,20 @@ int cmd_rnto(struct conn * const c)
  *		easy :-) (This code isn't quite easy to understand, because
  *		temp2 is used twice, in two different roles.)
  */
-int cmd_mkd(struct conn * const c)
+void cmd_mkd(struct conn * const c)
 {
 	const char * const fname = translate_path(c, c->recv_buf);
 	char temp[512], temp2[1024], *cdir;
 	int i, j;
 
-	TRAP_ERROR(fname == NULL || mkdir(fname, 0755) == -1, 550, return 1);
+	TRAP_ERROR(fname == NULL || mkdir(fname, 0755) == -1, 550, return);
 
 	chdir(fname);
 	getcwd(temp2, 512);
 	cdir = do_pwd(c, temp, temp2);
 
+	if (do_pwd == NULL) return;
+	
 	/* double the quotes in the output */ 
 	for (i = 0, j = 0; i <= strlen(cdir); i++, j++) {
 		temp2[j] = cdir[i];
@@ -861,20 +847,18 @@ int cmd_mkd(struct conn * const c)
 		}
 	}
 	numeric(c, 257, "\"%s\" created.", temp2);
-	return 1;
 }
 
 /*
  * cmd_rmd():	Handle the RMD/XRMD command. Works just like DELE, only for
  *		directories.
  */
-int cmd_rmd(struct conn * const c)
+void cmd_rmd(struct conn * const c)
 {
 	const char * const fname = translate_path(c, c->recv_buf);
 
-	TRAP_ERROR(fname == NULL || rmdir(fname) == -1, 550, return 1);
+	TRAP_ERROR(fname == NULL || rmdir(fname) == -1, 550, return);
 	numeric(c, 250, "Directory deleted.");
-	return 1;
 }
 
 /*
@@ -888,10 +872,9 @@ int cmd_rmd(struct conn * const c)
  *		to the full-screen mode, but close to no FTP clients send this
  *		command, and it would touch too much code.
  */
-int cmd_allo(struct conn * const c)
+void cmd_allo(struct conn * const c)
 {
 	numeric(c, 202, "No storage allocation necessary.");
-	return 1;
 }
 
 /*
@@ -908,7 +891,7 @@ char conn_state[5][27] = {
 	"Waiting for e-mail address",
 	"Waiting for password",
 	"Logged in",
-	"Waiting for password",		/* actually non-existant user */
+	"Logged in",		/* non-anonymous */
 };
 
 char ftran_state[6][42] = {
@@ -921,7 +904,7 @@ char ftran_state[6][42] = {
 };
 #endif
 
-int cmd_stat(struct conn * const c)
+void cmd_stat(struct conn * const c)
 { 
 #if WANT_STAT
 	char buf[1024];
@@ -950,13 +933,11 @@ int cmd_stat(struct conn * const c)
 
 	err = send(c->sock, buf, i, 0);
        	if (err == -1 && errno == EPIPE) {
-               	destroy_conn(c);
-		return 0;
+		this->free_me = 1;
 	}
 #else
 	numeric(c, 502, "STAT command disabled for security reasons.");
 #endif
-	return 1;
 }
 
 #if HAVE_MMAP
@@ -1106,7 +1087,7 @@ int long_listing(char * const retbuf, const char * const pathname, const int do_
  *		long listing (of type `ls -l'). The listing work is
  *		done by do_listing(), below.
  */
-int cmd_list(struct conn * const c)
+void cmd_list(struct conn * const c)
 {
 	struct list_options lo;
 
@@ -1115,7 +1096,6 @@ int cmd_list(struct conn * const c)
 	lo.classify = 0;
 
 	do_listing(c, &lo);
-	return 1;
 }
 
 /*
@@ -1125,7 +1105,7 @@ int cmd_list(struct conn * const c)
  *		FTP clients don't have a clue about what they send out). 
  *		The listing work is done by do_listing(), below.
  */	
-int cmd_nlst(struct conn * const c)
+void cmd_nlst(struct conn * const c)
 {
 	struct list_options lo;
 
@@ -1134,7 +1114,6 @@ int cmd_nlst(struct conn * const c)
 	lo.classify = 0;
 
 	do_listing(c, &lo);
-	return 1;
 }
 
 /*
@@ -1423,25 +1402,23 @@ int list_core(struct conn * const c, const char * const pathname,
  * cmd_noop():	Handles the NOOP command. Does nothing, doesn't even
  *		reset the timeout.
  */
-int cmd_noop(struct conn * const c)
+void cmd_noop(struct conn * const c)
 {
 	numeric(c, 200, "NOOP command successful.");
-	return 1;
 }
 
 /*
  * cmd_syst():	Handles the SYST command. Returns the system identification.
  */
-int cmd_syst(struct conn * const c)
+void cmd_syst(struct conn * const c)
 {
 	numeric(c, 215, "UNIX Type: L%u", NBBY);
-	return 1;
 }
 
 /*
  * cmd_type():	Handles the TYPE command.
  */
-int cmd_type(struct conn * const c)
+void cmd_type(struct conn * const c)
 {
 #if WANT_ASCII
 	c->recv_buf[0] &= (255-32);	/* convert to upper case */
@@ -1457,13 +1434,12 @@ int cmd_type(struct conn * const c)
 #else
 	numeric(c, 200, "TYPE ignored (always I)");
 #endif
-	return 1;
 }
 
 /*
  * cmd_mode():	Handles the MODE command. Only stream mode is supported.
  */
-int cmd_mode(struct conn * const c)
+void cmd_mode(struct conn * const c)
 {
  	c->recv_buf[0] &= (255-32);	/* convert to upper case */
 	if (c->recv_buf[0] == 'S') {
@@ -1471,13 +1447,12 @@ int cmd_mode(struct conn * const c)
 	} else {
 		numeric(c, 504, "Unknown mode.");
 	}
-	return 1;
 }
 
 /*
  * cmd_stru():	Handles the STRU command. Only file mode is supported.
  */
-int cmd_stru(struct conn * const c)
+void cmd_stru(struct conn * const c)
 {
 	c->recv_buf[0] &= (255-32);	/* convert to upper case */
 	if (c->recv_buf[0] == 'F') {
@@ -1485,7 +1460,6 @@ int cmd_stru(struct conn * const c)
 	} else {
 		numeric(c, 504, "Unknown structure.");
 	}
-	return 1;
 }
 
 /*
@@ -1505,21 +1479,19 @@ int cmd_stru(struct conn * const c)
  *		like an error, since the error code is intended for helpful
  *		messages? :-)
  */
-int cmd_help(struct conn * const c)
+void cmd_help(struct conn * const c)
 {
 	numeric(c, 414, "Sorry, no detailed help; use standard FTP commands.");
-	return 1;
 }
 
 /*
  * cmd_quit():	Handles the QUIT command, which shuts down the control
  *		and data sockets.
  */
-int cmd_quit(struct conn * const c)
+void cmd_quit(struct conn * const c)
 {
 	numeric(c, 221, "Have a nice day!");
-	destroy_conn(c);
-	return 0;
+	c->free_me = 1;
 }
 
 /*
@@ -1528,7 +1500,7 @@ int cmd_quit(struct conn * const c)
  *		copied directly from alloc_new_conn() -- perhaps we should
  *		modularize this?
  */
-int cmd_rein(struct conn * const c)
+void cmd_rein(struct conn * const c)
 {
 	destroy_ftran(c->transfer);
 	c->buf_len = c->auth = c->rest_pos = 0;
@@ -1543,8 +1515,6 @@ int cmd_rein(struct conn * const c)
 
 	time(&(c->last_transfer));
 	numeric(c, 220, "BetaFTPD " VERSION " ready.");
-
-	return 1;
 }
 
 #if DOING_PROFILING
@@ -1608,8 +1578,8 @@ void parse_command(struct conn *c)
 
 #if !WANT_NONROOT
 				if (h->do_setuid) {
-					seteuid(c->uid);
 					setegid(c->gid);
+					seteuid(c->uid);
 				} else {
 					seteuid(getuid());
 					setegid(getgid());
@@ -1625,9 +1595,18 @@ void parse_command(struct conn *c)
 
 				schar = c->recv_buf[cmlen];
 				c->recv_buf[cmlen] = 0;
-
-				/* result of zero means the connection is freed */
-				if (h->callback(c)) {
+				
+				message_buf[0] = '\0';
+				h->callback(c);
+				if (message_buf[0] != '\0') {
+					/* send any feedback we might have */
+				        int err = send(c->sock, message_buf, strlen(message_buf), 0);
+				        if (err == -1 && errno == EPIPE) {
+				                c->free_me = 1;
+				        }
+				}	
+				
+				if (!c->free_me) {
 					c->recv_buf[cmlen] = schar;
 #if !WANT_NONROOT
 					if (h->do_setuid) {
@@ -1642,8 +1621,12 @@ void parse_command(struct conn *c)
 		}
 	} while ((++h)->callback != NULL);
 
-	numeric(c, 500, "Sorry, no such command.");
 	remove_bytes(c, cmlen); 
+	{
+		char error[] = "500 Sorry, no such command.\r\n";
+		if (send(c->sock, error, strlen(error), 0) == -1 && errno == EPIPE)
+			destroy_conn(c);
+	}
 }
 
 /*
@@ -1844,7 +1827,7 @@ int prepare_for_listing(struct conn * const c, char ** const ptr,
 			case 'F':
 				lo->classify = 1;
 				break;
-			case ' ':
+			case '\0':
 				fptr = optr + 1;
 				*(optr--) = 0;
 				break;
@@ -1855,7 +1838,7 @@ int prepare_for_listing(struct conn * const c, char ** const ptr,
 	} else {
 		fptr = c->recv_buf;
 	}
-	
+
 	/* then we chdir to the dir in fptr (if any) */
 	tmp = fptr ? strrchr(fptr, '/') : NULL;
 	if (tmp != NULL) {