busybox/libbb/full_write.c
Denys Vlasenko 875ce094cf dd: fix handling of short result of full_write(), closes 11711
$ dd bs=1G <sda1 of=/dev/sda1
dd: error writing '/dev/sda1': No space left on device
1+0 records in
0+0 records out
999292928 bytes (953.0MB) copied, 0.784617 seconds, 1.2GB/s

function                                             old     new   delta
write_and_stats                                       99     102      +3

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2019-05-14 17:49:14 +02:00

43 lines
850 B
C

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
#include "libbb.h"
/*
* Write all of the supplied buffer out to a file.
* This does multiple writes as necessary.
* Returns the amount written, or -1 if error was seen
* on the very first write.
*/
ssize_t FAST_FUNC full_write(int fd, const void *buf, size_t len)
{
ssize_t cc;
ssize_t total;
total = 0;
while (len) {
cc = safe_write(fd, buf, len);
if (cc < 0) {
if (total) {
/* we already wrote some! */
/* user can do another write to know the error code */
return total;
}
return cc; /* write() returns -1 on failure. */
}
total += cc;
buf = ((const char *)buf) + cc;
len -= cc;
}
return total;
}