busybox/libbb/copyfd.c

91 lines
2.2 KiB
C
Raw Normal View History

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 1999-2003 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>
2003-11-22 07:43:41 +05:30
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
2003-03-19 14:43:01 +05:30
#include "busybox.h"
2003-11-22 07:43:41 +05:30
2003-03-19 14:43:01 +05:30
#if BUFSIZ < 4096
#undef BUFSIZ
#define BUFSIZ 4096
#endif
2003-11-22 07:43:41 +05:30
/* If size is 0 copy until EOF */
extern size_t bb_full_fd_action(int src_fd, int dst_fd, const size_t size, ssize_t (*action)(int fd, const void *, size_t))
{
size_t read_total = 0;
2003-03-19 14:43:01 +05:30
RESERVE_CONFIG_BUFFER(buffer,BUFSIZ);
2002-12-13 13:50:44 +05:30
while ((size == 0) || (read_total < size)) {
size_t read_try;
ssize_t read_actual;
2002-12-13 13:50:44 +05:30
if ((size == 0) || (size - read_total > BUFSIZ)) {
read_try = BUFSIZ;
} else {
read_try = size - read_total;
2002-12-13 13:50:44 +05:30
}
read_actual = safe_read(src_fd, buffer, read_try);
if (read_actual > 0) {
if (action && (action(dst_fd, buffer, (size_t) read_actual) != read_actual)) {
2003-03-19 14:43:01 +05:30
bb_perror_msg(bb_msg_write_error); /* match Read error below */
break;
}
}
else if (read_actual == 0) {
if (size) {
2003-03-19 14:43:01 +05:30
bb_error_msg("Unable to read all data");
2002-12-13 13:50:44 +05:30
}
break;
} else {
/* read_actual < 0 */
bb_perror_msg("Read error");
2003-03-19 14:43:01 +05:30
break;
2002-12-13 13:50:44 +05:30
}
read_total += read_actual;
}
RELEASE_CONFIG_BUFFER(buffer);
return(read_total);
}
extern int bb_copyfd_size(int fd1, int fd2, const off_t size)
{
if (size) {
return(bb_full_fd_action(fd1, fd2, size, bb_full_write));
}
return(0);
}
extern int bb_copyfd_eof(int fd1, int fd2)
{
return(bb_full_fd_action(fd1, fd2, 0, bb_full_write));
}