diff --git a/http.c b/http.c
index 673e6eb..efc4136 100644
--- a/http.c
+++ b/http.c
@@ -394,8 +394,10 @@ http_send_response(int fd, struct request *r)
 	for (i = 0; i < s.map_len; i++) {
 		len = strlen(s.map[i].from);
 		if (!strncmp(realtarget, s.map[i].from, len)) {
-			/* match canonical host if vhosts are enabled */
-			if (s.vhost && strcmp(s.map[i].chost, vhostmatch)) {
+			/* match canonical host if vhosts are enabled and
+			 * the mapping specifies a canonical host */
+			if (s.vhost && s.map[i].chost &&
+			    strcmp(s.map[i].chost, vhostmatch)) {
 				continue;
 			}
 
diff --git a/main.c b/main.c
index 9d193a5..46cf424 100644
--- a/main.c
+++ b/main.c
@@ -155,10 +155,12 @@ main(int argc, char *argv[])
 		                           sizeof(struct map)))) {
 			die("reallocarray:");
 		}
-		if (!(s.map[s.map_len - 1].chost = strtok(tok,  " ")) ||
-		    !(s.map[s.map_len - 1].from  = strtok(NULL, " ")) ||
-		    !(s.map[s.map_len - 1].to    = strtok(NULL, " ")) ||
-		    strtok(NULL, "")) {
+		if (!(s.map[s.map_len - 1].from  = strtok(tok,  " ")) ||
+		    !(s.map[s.map_len - 1].to    = strtok(NULL, " "))) {
+			usage();
+		}
+		s.map[s.map_len - 1].chost = strtok(NULL, " ");
+		if (strtok(NULL, "")) {
 			usage();
 		}
 		break;
diff --git a/quark.1 b/quark.1
index d9a76d8..67d120a 100644
--- a/quark.1
+++ b/quark.1
@@ -1,4 +1,4 @@
-.Dd 2019-02-18
+.Dd 2019-02-24
 .Dt QUARK 1
 .Os suckless.org
 .Sh NAME
@@ -57,16 +57,15 @@ Enable directory listing.
 Add the target prefix mapping rule specified by
 .Ar map ,
 which has the form
-.Qq Pa chost from to ,
+.Qq Pa from to [chost] ,
 where each element is separated with whitespace.
 .Pp
 The prefix
 .Pa from
-of all matching targets, especially only of those requests for the canonical
-virtual host
-.Pa chost
-when virtual hosts are specified, is then replaced with
-.Pa to .
+of all matching targets is replaced with
+.Pa to ,
+optionally limited to the canonical virtual host
+.Pa chost .
 If no virtual hosts are given,
 .Pa chost
 is ignored.