freebsd-skq/contrib/elftoolchain/libelftc/elftc_copyfile.c
emaste 46be049bf4 Update elftoolchain to upstream rev 3130
This brings a number of fixes to elfcopy/strip and DWARF4 improvements.

Sponsored by:	The FreeBSD Foundation
2014-12-24 03:13:16 +00:00

110 lines
2.8 KiB
C

/*-
* Copyright (c) 2011, Joseph Koshy
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. 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 AUTHOR(S) ``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 AUTHOR(S) 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 <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <unistd.h>
#include "libelftc.h"
#include "_libelftc.h"
#if ELFTC_HAVE_MMAP
#include <sys/mman.h>
#endif
ELFTC_VCSID("$Id: elftc_copyfile.c 2981 2014-02-01 02:41:13Z jkoshy $");
/*
* Copy the contents referenced by 'ifd' to 'ofd'. Returns 0 on
* success and -1 on error.
*/
int
elftc_copyfile(int ifd, int ofd)
{
int buf_mmapped;
struct stat sb;
char *b, *buf;
ssize_t nw;
size_t n;
/* Determine the input file's size. */
if (fstat(ifd, &sb) < 0)
return (-1);
/* Skip files without content. */
if (sb.st_size == 0)
return (0);
buf = NULL;
buf_mmapped = 0;
#if ELFTC_HAVE_MMAP
/*
* Prefer mmap() if it is available.
*/
buf = mmap(NULL, sb.st_size, PROT_READ, MAP_SHARED, ifd, (off_t) 0);
if (buf != MAP_FAILED)
buf_mmapped = 1;
else
buf = NULL;
#endif
/*
* If mmap() is not available, or if the mmap() operation
* failed, allocate a buffer, and read in input data.
*/
if (buf_mmapped == false) {
if ((buf = malloc(sb.st_size)) == NULL)
return (-1);
if (read(ifd, buf, sb.st_size) != sb.st_size) {
free(buf);
return (-1);
}
}
/*
* Write data to the output file descriptor.
*/
for (n = sb.st_size, b = buf; n > 0; n -= nw, b += nw)
if ((nw = write(ofd, b, n)) <= 0)
break;
/* Release the input buffer. */
#if ELFTC_HAVE_MMAP
if (buf_mmapped && munmap(buf, sb.st_size) < 0)
return (-1);
#endif
if (!buf_mmapped)
free(buf);
return (n > 0 ? -1 : 0);
}