Fix helper reply length detection

Stateless helper reply handler was incrementing 't' position before
passing the details of response length to HelperReply parser.

Stateful helper reply handler was pointing at position of \n insteaf of
position of \r when \r\n received.

Both of these cause the response length parameter sent to the reply
parser to be longer than the actual response characters length. Breaking
parse on responses with just result code followed by \n since the string
comparison EOL is now tested against input length 2/3/4.

diff --git a/src/helper.cc b/src/helper.cc
index fe07223d075b5c65c0aff5192fc4a79b63ec9de6..196a6a677c2da8372920ad7d817918a46dc0497d 100644 (file)
--- a/src/helper.cc
+++ b/src/helper.cc
@@ -942,7 +942,6 @@ helperHandleRead(const Comm::ConnectionPointer &conn, char *buf, size_t len, com
             t[-1] = '\0';
 
         *t = '\0';
-        ++t;
 
         if (hlp->childs.concurrency) {
             i = strtol(msg, &msg, 10);
@@ -952,6 +951,8 @@ helperHandleRead(const Comm::ConnectionPointer &conn, char *buf, size_t len, com
         }
 
         helperReturnBuffer(i, srv, hlp, msg, t);
+        // only skip off the \0 _after_ passing its location to helperReturnBuffer
+        ++t;
     }
 
     if (Comm::IsConnOpen(srv->readPipe)) {
@@ -1023,10 +1024,16 @@ helperStatefulHandleRead(const Comm::ConnectionPointer &conn, char *buf, size_t
     if ((t = strchr(srv->rbuf, hlp->eom))) {
         /* end of reply found */
         int called = 1;
+        int skip = 1;
         debugs(84, 3, "helperStatefulHandleRead: end of reply found");
 
-        if (t > srv->rbuf && t[-1] == '\r' && hlp->eom == '\n')
-            t[-1] = '\0';
+        if (t > srv->rbuf && t[-1] == '\r' && hlp->eom == '\n') {
+            *t = '\0';
+            // rewind to the \r octet which is the real terminal now
+            // and remember that we have to skip forward 2 places now.
+            skip = 2;
+            --t;
+        }
 
         *t = '\0';
 
@@ -1038,6 +1045,8 @@ helperStatefulHandleRead(const Comm::ConnectionPointer &conn, char *buf, size_t
             debugs(84, DBG_IMPORTANT, "StatefulHandleRead: no callback data registered");
             called = 0;
         }
+        // only skip off the \0's _after_ passing its location in HelperReply above
+        t += skip;
 
         srv->flags.busy = 0;
         srv->roffset = 0;