curl_multi_wait: reduce timeout if the multi handle wants to

If the multi handle's pending timeout is less than what is passed into
this function, it will now opt to use the shorter time anyway since it
is a very good hint that the handle wants to process something in a
shorter time than what otherwise would happen.

curl_multi_wait.3 was updated accordingly to clarify

This is the reason for bug #1224

Bug: http://curl.haxx.se/bug/view.cgi?id=1224
Reported-by: Andrii Moiseiev
This commit is contained in:
Daniel Stenberg 2013-06-03 20:19:51 +02:00
parent 239b58d34d
commit 29bf0598aa
2 changed files with 13 additions and 1 deletions

View File

@ -5,7 +5,7 @@
.\" * | (__| |_| | _ <| |___
.\" * \___|\___/|_| \_\_____|
.\" *
.\" * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>, et al.
.\" * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
.\" *
.\" * This software is licensed as described in the file COPYING, which
.\" * you should have received as part of this distribution. The terms
@ -36,6 +36,9 @@ CURLMcode curl_multi_wait(CURLM *multi_handle,
This function polls on all file descriptors used by the curl easy handles
contained in the given multi handle set. It will block until activity is
detected on at least one of the handles or \fItimeout_ms\fP has passed.
Alternatively, if the multi handle has a pending internal timeout that has a
shorter expiry time than \fItimeout_ms\fP, that shorter time will be used
instead to make sure timeout accuracy is reasonably kept.
The calling application may pass additional curl_waitfd structures which are
similar to \fIpoll(2)\fP's pollfd structure to be waited on in the same call.

View File

@ -76,6 +76,8 @@ static bool isHandleAtHead(struct SessionHandle *handle,
static CURLMcode add_next_timeout(struct timeval now,
struct Curl_multi *multi,
struct SessionHandle *d);
static CURLMcode multi_timeout(struct Curl_multi *multi,
long *timeout_ms);
#ifdef DEBUGBUILD
static const char * const statename[]={
@ -810,10 +812,17 @@ CURLMcode curl_multi_wait(CURLM *multi_handle,
unsigned int nfds = 0;
unsigned int curlfds;
struct pollfd *ufds = NULL;
long timeout_internal;
if(!GOOD_MULTI_HANDLE(multi))
return CURLM_BAD_HANDLE;
/* If the internally desired timeout is actually shorter than requested from
the outside, then use the shorter time! */
(void)multi_timeout(multi, &timeout_internal);
if(timeout_internal < (long)timeout_ms)
timeout_ms = (int)timeout_internal;
/* Count up how many fds we have from the multi handle */
easy=multi->easy.next;
while(easy != &multi->easy) {