Curl_GetFTPResponse() now checks and properly deals with the fact that the

underlying ftp_readresp() function has a separate "cache" where there might
in fact be leftover data...

CHANGES

@@ -6,6 +6,12 @@
 
                                   Changelog
 
+Daniel S (5 September 2007)
+- Continued the work on a fix for #1779054
+  (http://curl.haxx.se/bug/view.cgi?id=1779054). My previous fix from August
+  24 was not complete (either) but could accidentally "forget" parts of a
+  server response which led to faulty server response time-out errors.
+
 Dan F (5 September 2007)
 - Minix doesn't support getsockopt on UDP sockets or send/recv on TCP
   sockets.

lib/ftp.c

@@ -537,6 +537,7 @@ CURLcode Curl_GetFTPResponse(ssize_t *nreadp, /* return number of bytes read */
   struct ftp_conn *ftpc = &conn->proto.ftpc;
   struct timeval now = Curl_tvnow();
   size_t nread;
+  int cache_skip=0;
 
   if (ftpcode)
     *ftpcode = 0; /* 0 for errors */
@@ -572,6 +573,29 @@ CURLcode Curl_GetFTPResponse(ssize_t *nreadp, /* return number of bytes read */
     if(timeout < interval_ms)
       interval_ms = timeout;
 
+    /*
+     * Since this function is blocking, we need to wait here for input on the
+     * connection and only then we call the response reading function. We do
+     * timeout at least every second to make the timeout check run.
+     *
+     * A caution here is that the ftp_readresp() function has a cache that may
+     * contain pieces of a response from the previous invoke and we need to
+     * make sure we don't just wait for input while there is unhandled data in
+     * that cache. But also, if the cache is there, we call ftp_readresp() and
+     * the cache wasn't good enough to continue we must not just busy-loop
+     * around this function.
+     *
+     */
+
+    if(ftpc->cache && (cache_skip < 2)) {
+      /*
+       * There's a cache left since before. We then skipping the wait for
+       * socket action, unless this is the same cache like the previous round
+       * as then the cache was deemed not enough to act on and we then need to
+       * wait for more data anyway.
+       */
+    }
+    else {
       switch (Curl_socket_ready(sockfd, CURL_SOCKET_BAD, (int)interval_ms)) {
       case -1: /* select() error, stop reading */
         failf(data, "FTP response aborted due to select/poll error: %d",
@@ -586,11 +610,20 @@ CURLcode Curl_GetFTPResponse(ssize_t *nreadp, /* return number of bytes read */
       default: /* for clarity */
         break;
       }
-
+    }
     result = ftp_readresp(sockfd, conn, ftpcode, &nread);
     if(result)
       break;
 
+    if(!nread && ftpc->cache)
+      /* bump cache skip counter as on repeated skips we must wait for more
+         data */
+      cache_skip++;
+    else
+      /* when we got data or there is no cache left, we reset the cache skip
+         counter */
+      cache_skip=0;
+
     *nreadp += nread;
 
   } /* while there's buffer left and loop is requested */