hush/libbb/safe_poll.c
Denis Vlasenko 5d61e71c3a introduce safe_poll (fixes a problem in top)
function                                             old     new   delta
safe_poll                                              -      77     +77
svlogd_main                                         1470    1466      -4
zcip_main                                           1530    1524      -6
forkexec                                            1345    1338      -7
decode_format_string                                 795     788      -7
collect_blk                                          474     467      -7
buffer_pread                                         540     532      -8
tftp                                                1182    1172     -10
microcom_main                                        763     749     -14
arpping                                              441     424     -17
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/9 up/down: 77/-80)             Total: -3 bytes
   text    data     bss     dec     hex filename
 770162    1034   10404  781600   bed20 busybox_old
 770158    1034   10404  781596   bed1c busybox_unstripped
2007-09-27 10:09:59 +00:00

35 lines
860 B
C

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 2007 by Denys Vlasenko <vda.linux@googlemail.com>
*
* Licensed under GPLv2, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
/* Wrapper which restarts poll on EINTR or ENOMEM.
* On other errors does perror("poll") and returns.
* Warning! May take longer than timeout_ms to return! */
int safe_poll(struct pollfd *ufds, nfds_t nfds, int timeout)
{
while (1) {
int n = poll(ufds, nfds, timeout);
if (n >= 0)
return n;
/* Make sure we inch towards completion */
if (timeout > 0)
timeout--;
/* E.g. strace causes poll to return this */
if (errno == EINTR)
continue;
/* Kernel is very low on memory. Retry. */
/* I doubt many callers would handle this correctly! */
if (errno == ENOMEM)
continue;
bb_perror_msg("poll");
return n;
}
}