Robson Braga Araujo reported bug #1618359

(http://curl.haxx.se/bug/view.cgi?id=1618359) and subsequently provided a
patch for it: when downloading 2 zero byte files in a row, curl 7.16.0
enters an infinite loop, while curl 7.16.1-20061218 does one additional
unnecessary request.

Fix: During the "Major overhaul introducing http pipelining support and
shared connection cache within the multi handle." change, headerbytecount
was moved to live in the Curl_transfer_keeper structure. But that structure
is reset in the Transfer method, losing the information that we had about
the header size. This patch moves it back to the connectdata struct.

CHANGES

@@ -6,6 +6,19 @@
 
                                   Changelog
 
+Daniel (21 December 2006)
+- Robson Braga Araujo reported bug #1618359
+  (http://curl.haxx.se/bug/view.cgi?id=1618359) and subsequently provided a
+  patch for it: when downloading 2 zero byte files in a row, curl 7.16.0
+  enters an infinite loop, while curl 7.16.1-20061218 does one additional
+  unnecessary request.
+
+  Fix: During the "Major overhaul introducing http pipelining support and
+  shared connection cache within the multi handle." change, headerbytecount
+  was moved to live in the Curl_transfer_keeper structure. But that structure
+  is reset in the Transfer method, losing the information that we had about
+  the header size. This patch moves it back to the connectdata struct.
+
 Daniel (16 December 2006)
 - Brendan Jurd provided a fix that now prevents libcurl from getting a SIGPIPE
   during certain conditions when GnuTLS is used.

RELEASE-NOTES

@@ -36,6 +36,7 @@ This release includes the following bugfixes:
  o getting FTP response code errors when using the multi-interface caused
    libcurl to leak memory
  o no more SIGPIPE when GnuTLS is used
+ o FTP downloading 2 zero byte files in a row
 
 Other curl-related news:
 
@@ -54,6 +55,7 @@ advice from friends like these:
  James Housley, Olaf Stueben, Yang Tse, Gisle Vanem, Bradford Bruce,
  Ciprian Badescu, Dmitriy Sergeyev, Nir Soffer, Venkat Akella, Toon Verwaest,
  Matt Witherspoon, Alexey Simak, Martin Skinner, Sh Diao, Jared Lundell,
- Stefan Krause, Sebastien Willemijns, Alexey Simak, Brendan Jurd
+ Stefan Krause, Sebastien Willemijns, Alexey Simak, Brendan Jurd,
+ Robson Braga Araujo
 
         Thanks! (and sorry if I forgot to mention someone)

lib/ftp.c

@@ -329,7 +329,7 @@ static CURLcode ftp_readresp(curl_socket_t sockfd,
        * line */
       int i;
 
-      k->headerbytecount += gotbytes;
+      conn->headerbytecount += gotbytes;
 
       ftpc->nread_resp += gotbytes;
       for(i = 0; i < gotbytes; ptr++, i++) {
@@ -562,7 +562,7 @@ CURLcode Curl_GetFTPResponse(ssize_t *nreadp, /* return number of bytes read */
          * line */
         int i;
 
-        k->headerbytecount += gotbytes;
+        conn->headerbytecount += gotbytes;
 
         *nreadp += gotbytes;
         for(i = 0; i < gotbytes; ptr++, i++) {

lib/http.c

@@ -1527,8 +1527,8 @@ CURLcode Curl_http_done(struct connectdata *conn,
 
   if(!conn->bits.retry &&
      ((http->readbytecount +
-       k->headerbytecount -
-       k->deductheadercount)) <= 0) {
+       conn->headerbytecount -
+       conn->deductheadercount)) <= 0) {
     /* If this connection isn't simply closed to be retried, AND nothing was
        read from the HTTP server (that counts), this can't be right so we
        return an error here */

lib/transfer.c

@@ -581,10 +581,10 @@ CURLcode Curl_readwrite(struct connectdata *conn,
                 return result;
 
               data->info.header_size += (long)headerlen;
-              k->headerbytecount += (long)headerlen;
+              conn->headerbytecount += (long)headerlen;
 
-              k->deductheadercount =
-                (100 == k->httpcode)?k->headerbytecount:0;
+              conn->deductheadercount =
+                (100 == k->httpcode)?conn->headerbytecount:0;
 
               if (data->reqdata.resume_from &&
                   (data->set.httpreq==HTTPREQ_GET) &&
@@ -1040,7 +1040,7 @@ CURLcode Curl_readwrite(struct connectdata *conn,
               return result;
 
             data->info.header_size += (long)k->hbuflen;
-            k->headerbytecount += (long)k->hbuflen;
+            conn->headerbytecount += (long)k->hbuflen;
 
             /* reset hbufp pointer && hbuflen */
             k->hbufp = data->state.headerbuff;
@@ -1564,7 +1564,6 @@ CURLcode Curl_readwrite_init(struct connectdata *conn)
   k->writebytecountp = data->reqdata.writebytecountp;
 
   k->bytecount = 0;
-  k->headerbytecount = 0;
 
   k->buf = data->state.buffer;
   k->uploadbuf = data->state.uploadbuffer;
@@ -2247,7 +2246,7 @@ bool Curl_retry_request(struct connectdata *conn,
   struct SessionHandle *data = conn->data;
   struct Curl_transfer_keeper *k = &data->reqdata.keep;
 
-  if((data->reqdata.keep.bytecount+k->headerbytecount == 0) &&
+  if((data->reqdata.keep.bytecount+conn->headerbytecount == 0) &&
      conn->bits.reuse &&
      !conn->bits.no_body) {
     /* We got no data, we attempted to re-use a connection and yet we want a

lib/url.c

@@ -3964,6 +3964,8 @@ static CURLcode SetupConnection(struct connectdata *conn,
     }
   }
 
+  conn->headerbytecount = 0;
+
 #ifdef CURL_DO_LINEEND_CONV
   data->state.crlf_conversions = 0; /* reset CRLF conversion counter */
 #endif /* CURL_DO_LINEEND_CONV */

lib/urldata.h

@@ -534,13 +534,6 @@ struct Curl_transfer_keeper {
   curl_off_t bytecount;         /* total number of bytes read */
   curl_off_t writebytecount;    /* number of bytes written */
 
-  long headerbytecount;  /* only count received headers */
-  long deductheadercount; /* this amount of bytes doesn't count when we check
-                             if anything has been transfered at the end of
-                             a connection. We use this counter to make only
-                             a 100 reply (without a following second response
-                             code) result in a CURLE_GOT_NOTHING error code */
-
   struct timeval start;         /* transfer started at this time */
   struct timeval now;           /* current time */
   bool header;                  /* incoming data has HTTP header */
@@ -742,6 +735,13 @@ struct connectdata {
   unsigned short remote_port; /* what remote port to connect to,
                                  not the proxy port! */
 
+  long headerbytecount;  /* only count received headers */
+  long deductheadercount; /* this amount of bytes doesn't count when we check
+                             if anything has been transfered at the end of
+                             a connection. We use this counter to make only
+                             a 100 reply (without a following second response
+                             code) result in a CURLE_GOT_NOTHING error code */
+
   char *user;    /* user name string, allocated */
   char *passwd;  /* password string, allocated */