bionic/libc/unistd/usleep.c
Elliott Hughes 99d7907611 Fix usleep(3) return type to be POSIX-compliant.
POSIX usleep(3) returns 0 on successful completion, -1 otherwise:
  http://www.opengroup.org/onlinepubs/007908799/xsh/usleep.html

This was found by an external user porting native code:
  http://groups.google.com/group/android-porting/browse_thread/thread/674848f001db0292
2009-12-14 17:07:19 -08:00

56 lines
1.9 KiB
C

/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <time.h>
#include <errno.h>
int usleep(unsigned long usec)
{
struct timespec ts;
ts.tv_sec = usec/1000000UL;
#ifdef __arm__
/* avoid divisions and modulos on the ARM */
ts.tv_nsec = (usec - ts.tv_sec*1000000UL)*1000;
#else
ts.tv_nsec = (usec % 1000000UL) * 1000UL;
#endif
for (;;)
{
if ( nanosleep( &ts, &ts ) == 0 )
return 0;
// We try again if the nanosleep failure is EINTR.
// The other possible failures are EINVAL (which we should pass through),
// and ENOSYS, which doesn't happen.
if ( errno != EINTR )
return -1;
}
}