urlapi: Fix port parsing of eol colon

A URL with a single colon without a portnumber should use the default
port, discarding the colon. Fix, add a testcase and also do little bit
of comment wordsmithing.

Closes #3365
Reviewed-by: Daniel Stenberg <daniel@haxx.se>

2 files changed, 24 insertions, 16 deletions

diff --git a/lib/urlapi.c b/lib/urlapi.c
index 5cbda6a98..e68748818 100644
--- a/lib/urlapi.c
+++ b/lib/urlapi.c
@@ -534,6 +534,14 @@ UNITTEST CURLUcode Curl_parse_port(struct Curl_URL *u, char *hostname)
     long port;
     char portbuf[7];
 
+    /* Browser behavior adaptation. If there's a colon with no digits after,
+       just cut off the name there which makes us ignore the colon and just
+       use the default port. Firefox, Chrome and Safari all do that. */
+    if(!portptr[1]) {
+      *portptr = '\0';
+      return CURLUE_OK;
+    }
+
     if(!ISDIGIT(portptr[1]))
       return CURLUE_BAD_PORT_NUMBER;
 
@@ -547,22 +555,14 @@ UNITTEST CURLUcode Curl_parse_port(struct Curl_URL *u, char *hostname)
     if(rest[0])
       return CURLUE_BAD_PORT_NUMBER;
 
-    if(rest != &portptr[1]) {
-      *portptr++ = '\0'; /* cut off the name there */
-      *rest = 0;
-      /* generate a new to get rid of leading zeroes etc */
-      msnprintf(portbuf, sizeof(portbuf), "%ld", port);
-      u->portnum = port;
-      u->port = strdup(portbuf);
-      if(!u->port)
-        return CURLUE_OUT_OF_MEMORY;
-    }
-    else {
-      /* Browser behavior adaptation. If there's a colon with no digits after,
-         just cut off the name there which makes us ignore the colon and just
-         use the default port. Firefox and Chrome both do that. */
-      *portptr = '\0';
-    }
+    *portptr++ = '\0'; /* cut off the name there */
+    *rest = 0;
+    /* generate a new port number string to get rid of leading zeroes etc */
+    msnprintf(portbuf, sizeof(portbuf), "%ld", port);
+    u->portnum = port;
+    u->port = strdup(portbuf);
+    if(!u->port)
+      return CURLUE_OUT_OF_MEMORY;
   }
 
   return CURLUE_OK;
diff --git a/tests/unit/unit1653.c b/tests/unit/unit1653.c
index 9851ee58c..b68d8dc4f 100644
--- a/tests/unit/unit1653.c
+++ b/tests/unit/unit1653.c
@@ -110,6 +110,14 @@ UNITTEST_START
   free(ipv6port);
   curl_url_cleanup(u);
 
+  /* Valid IPv6 with no port after the colon, should use default */
+  u = curl_url();
+  ipv6port = strdup("[fe80::250:56ff:fea7:da15]:");
+  ret = Curl_parse_port(u, ipv6port);
+  fail_unless(ret == CURLUE_OK, "Curl_parse_port returned error");
+  free(ipv6port);
+  curl_url_cleanup(u);
+
   /* Incorrect zone index syntax */
   u = curl_url();
   ipv6port = strdup("[fe80::250:56ff:fea7:da15%!25eth3]:80");