diff options
| -rw-r--r-- | CHANGES | 7 | ||||
| -rw-r--r-- | RELEASE-NOTES | 2 | ||||
| -rw-r--r-- | lib/multi.c | 13 |
3 files changed, 21 insertions, 1 deletions
@@ -7,6 +7,13 @@ Changelog Daniel Stenberg (19 Dec 2008) +- curl_multi_timeout() could return a timeout value of 0 even though nothing + was actually ready to get done, as the internal time resolution is higher + than the returned millisecond timer. Therefore it could cause applications + running on fast processors to do short bursts of busy-loops. + curl_multi_timeout() will now only return 0 if the timeout is actually + alreay triggered. + - Using the libssh2 0.19 function libssh2_session_block_directions(), libcurl now has an improved ability to do right when the multi interface (both "regular" and multi_socket) is used for SCP and SFTP transfers. This should diff --git a/RELEASE-NOTES b/RELEASE-NOTES index 0f33d2bb4..3ce349166 100644 --- a/RELEASE-NOTES +++ b/RELEASE-NOTES @@ -34,6 +34,8 @@ This release includes the following bugfixes: o improved connection re-use for subsequent SCP and SFTP transfers o multi interface does less busy-loops for SCP and SFTP transfers with libssh2 0.19 or later + o curl_multi_timeout() no longer returns timeout 0 when there's nothing to do + yet This release includes the following known bugs: diff --git a/lib/multi.c b/lib/multi.c index f17b33377..97efc7066 100644 --- a/lib/multi.c +++ b/lib/multi.c @@ -1541,6 +1541,7 @@ CURLMcode curl_multi_perform(CURLM *multi_handle, int *running_handles) if( CURLM_OK >= returncode ) update_timer(multi); + return returncode; } @@ -1951,9 +1952,19 @@ static CURLMcode multi_timeout(struct Curl_multi *multi, /* splay the lowest to the bottom */ multi->timetree = Curl_splay(tv_zero, multi->timetree); - if(Curl_splaycomparekeys(multi->timetree->key, now) > 0) + if(Curl_splaycomparekeys(multi->timetree->key, now) > 0) { /* some time left before expiration */ *timeout_ms = curlx_tvdiff(multi->timetree->key, now); + if(!*timeout_ms) + /* + * Since we only provide millisecond resolution on the returned value + * and the diff might be less than one millisecond here, we don't + * return zero as that may cause short bursts of busyloops on fast + * processors while the diff is still present but less than one + * millisecond! instead we return 1 until the time is ripe. + */ + *timeout_ms=1; + } else /* 0 means immediately */ *timeout_ms = 0; |