Make url_read_complete handle EAGAIN more intelligently.

Only retry 2 - 5 times in quick succession and afterwards sleep a bit
to avoid creating high CPU load without any progress.

Originally committed as revision 21427 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Reimar Döffinger 2010-01-24 18:09:46 +00:00
parent 0b882b4009
commit f1d2b5728c

View File

@ -19,6 +19,9 @@
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/* needed for usleep() */
#define _XOPEN_SOURCE 600
#include <unistd.h>
#include "libavutil/avstring.h"
#include "libavcodec/opt.h"
#include "os_support.h"
@ -152,14 +155,21 @@ int url_read(URLContext *h, unsigned char *buf, int size)
int url_read_complete(URLContext *h, unsigned char *buf, int size)
{
int ret, len;
int fast_retries = 5;
len = 0;
while (len < size) {
ret = url_read(h, buf+len, size-len);
if (ret == AVERROR(EAGAIN)) {
ret = 0;
if (fast_retries)
fast_retries--;
else
usleep(1000);
} else if (ret < 1)
return ret < 0 ? ret : len;
if (ret)
fast_retries = FFMAX(fast_retries, 2);
len += ret;
}
return len;