hush/libbb/copyfd.c

100 lines
2.2 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 1999-2005 by Erik Andersen <andersen@codepoet.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "busybox.h"
#include "libbb.h"
#if BUFSIZ < 4096
#undef BUFSIZ
#define BUFSIZ 4096
#endif
static size_t bb_full_fd_action(int src_fd, int dst_fd, const size_t size2)
{
int status;
size_t xread, wrote, total, size = size2;
if ((dst_fd < 0) || (src_fd < 0)) {
return -1;
}
if (size == 0) {
/* If size is 0 copy until EOF */
size = ULONG_MAX;
}
{
RESERVE_CONFIG_BUFFER(buffer,BUFSIZ);
total = 0;
wrote = 0;
status = -1;
while (total < size)
{
xread = BUFSIZ;
if (size < (wrote + BUFSIZ))
xread = size - wrote;
xread = bb_full_read(src_fd, buffer, xread);
if (xread > 0) {
wrote = bb_full_write(dst_fd, buffer, xread);
if (wrote < xread) {
bb_perror_msg(bb_msg_write_error);
break;
}
total += wrote;
} else if (xread < 0) {
bb_perror_msg(bb_msg_read_error);
break;
} else if (xread == 0) {
/* All done. */
status = 0;
break;
}
}
RELEASE_CONFIG_BUFFER(buffer);
}
if (status == 0 || wrote)
return wrote;
/* Some sortof error occured */
return -1;
}
extern int bb_copyfd_size(int fd1, int fd2, const off_t size)
{
if (size) {
return(bb_full_fd_action(fd1, fd2, size));
}
return(0);
}
extern int bb_copyfd_eof(int fd1, int fd2)
{
return(bb_full_fd_action(fd1, fd2, 0));
}