Not sure, that mainline needs it, but it may be good for the
people, using libcurl at low memory (some embedded) systems.

It safes 16K per client from the total ~60K.

The patch is against 7.16.2 inlined as well as attached.
---------------------------------------------------------------------------------
diff -Naru curl-7.16.2/lib/multi.c curl-7.16.2-mod/lib/multi.c
--- curl-7.16.2/lib/multi.c 2007-04-20 14:26:51.000000000 +0300
+++ curl-7.16.2-mod/lib/multi.c 2007-04-20 13:57:17.000000000 +0300
@@ -1765,6 +1765,8 @@
                             CURLMoption option, ...)
 {
   struct Curl_multi *multi=(struct Curl_multi *)multi_handle;
+ struct Curl_one_easy *easy;
+ bool pipelining_alloc_failed = false;
   CURLMcode res = CURLM_OK;
   va_list param;

@@ -1781,7 +1783,35 @@
     multi->socket_userp = va_arg(param, void *);
     break;
   case CURLMOPT_PIPELINING:
- multi->pipelining_enabled = (bool)(0 != va_arg(param, long));
+ /* Traverse all easy handles and allocate master_buffer for pipelining */
+ easy=multi->easy.next;
+ while(easy != &multi->easy) {
+ if (easy->easy_conn->master_buffer == NULL) {
+ if (!(easy->easy_conn->master_buffer =
+ calloc (BUFSIZE, sizeof (char)))) {
+ pipelining_alloc_failed = true;
+ break;
+ }
+ }
+ easy = easy->next; /* check next handle */
+ }
+
+ if (pipelining_alloc_failed) {
+ /* Traverse all easy handles and release master_buffer, where exists */
+ easy=multi->easy.next;
+ while(easy != &multi->easy) {
+ if (easy->easy_conn->master_buffer) {
+ free (easy->easy_conn->master_buffer);
+ easy->easy_conn->master_buffer = NULL;
+ }
+ easy = easy->next; /* check next handle */
+ }
+ res = CURLM_OUT_OF_MEMORY;
+ }
+
+ if (!pipelining_alloc_failed) {
+ multi->pipelining_enabled = (bool)(0 != va_arg(param, long));
+ }
     break;
   case CURLMOPT_TIMERFUNCTION:
     multi->timer_cb = va_arg(param, curl_multi_timer_callback);
diff -Naru curl-7.16.2/lib/sendf.c curl-7.16.2-mod/lib/sendf.c
--- curl-7.16.2/lib/sendf.c 2007-04-20 14:27:15.000000000 +0300
+++ curl-7.16.2-mod/lib/sendf.c 2007-04-20 14:13:37.000000000 +0300
@@ -496,7 +496,7 @@
     }
     /* If we come here, it means that there is no data to read from the buffer,
      * so we read from the socket */
- bytesfromsocket = MIN(sizerequested, sizeof(conn->master_buffer));
+ bytesfromsocket = MIN(sizerequested, BUFSIZE * sizeof (char));
     buffertofill = conn->master_buffer;
   }
   else {
diff -Naru curl-7.16.2/lib/transfer.c curl-7.16.2-mod/lib/transfer.c
--- curl-7.16.2/lib/transfer.c 2007-04-20 14:26:51.000000000 +0300
+++ curl-7.16.2-mod/lib/transfer.c 2007-04-20 14:19:28.000000000 +0300
@@ -289,8 +289,13 @@
     size_t show;

     show = MIN(conn->buf_len - conn->read_pos, sizeof(buf)-1);
- memcpy(buf, conn->master_buffer + conn->read_pos, show);
- buf[show] = '\0';
+ if (conn->master_buffer) {
+ memcpy(buf, conn->master_buffer + conn->read_pos, show);
+ buf[show] = '\0';
+ }
+ else {
+ buf[0] = '\0';
+ }

     DEBUGF(infof(conn->data,
                  "Buffer after stream rewind (read_pos = %d): [%s]",
diff -Naru curl-7.16.2/lib/url.c curl-7.16.2-mod/lib/url.c
--- curl-7.16.2/lib/url.c 2007-04-10 23:46:40.000000000 +0300
+++ curl-7.16.2-mod/lib/url.c 2007-04-20 14:50:51.000000000 +0300
@@ -1805,6 +1805,8 @@

   Curl_free_ssl_config(&conn->ssl_config);

+ Curl_safefree(conn->master_buffer);
+
   free(conn); /* free all the connection oriented data */
 }

diff -Naru curl-7.16.2/lib/urldata.h curl-7.16.2-mod/lib/urldata.h
--- curl-7.16.2/lib/urldata.h 2007-04-20 14:26:51.000000000 +0300
+++ curl-7.16.2-mod/lib/urldata.h 2007-04-20 13:46:56.000000000 +0300
@@ -868,7 +868,8 @@
   struct curl_llist *recv_pipe; /* List of handles waiting to read
                                    their responses on this pipeline */

- char master_buffer[BUFSIZE]; /* The master buffer for this connection. */
+ char* master_buffer; /* The master buffer allocated on-demand;
+ used for pipelining. */
   size_t read_pos; /* Current read position in the master buffer */
   size_t buf_len; /* Length of the buffer?? */

------------------------------------------------------------------------------------------------------------------

-- 
Sincerely,
Robert Iakobashvili,
coroberti %x40 gmail %x2e com
...................................................................
Navigare necesse est, vivere non est necesse
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