diff options
Diffstat (limited to 'release/src/router/busybox/libbb/copy_file_chunk.c')
-rw-r--r-- | release/src/router/busybox/libbb/copy_file_chunk.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/release/src/router/busybox/libbb/copy_file_chunk.c b/release/src/router/busybox/libbb/copy_file_chunk.c new file mode 100644 index 00000000..c440a610 --- /dev/null +++ b/release/src/router/busybox/libbb/copy_file_chunk.c @@ -0,0 +1,74 @@ +/* vi: set sw=4 ts=4: */ +/* + * Utility routines. + * + * Copyright (C) tons of folks. Tracking down who wrote what + * isn't something I'm going to worry about... If you wrote something + * here, please feel free to acknowledge your work. + * + * 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 + * + * Based in part on code from sash, Copyright (c) 1999 by David I. Bell + * Permission has been granted to redistribute this code under the GPL. + * + */ + +#include <stdio.h> +#include <sys/stat.h> +#include "libbb.h" + +/* Copy CHUNKSIZE bytes (or until EOF if CHUNKSIZE equals -1) from SRC_FILE + * to DST_FILE. */ +extern int copy_file_chunk(FILE *src_file, FILE *dst_file, unsigned long long chunksize) +{ + size_t nread, nwritten, size; + char buffer[BUFSIZ]; + + while (chunksize != 0) { + if (chunksize > BUFSIZ) + size = BUFSIZ; + else + size = chunksize; + + nread = fread (buffer, 1, size, src_file); + + if (nread != size && ferror (src_file)) { + perror_msg ("read"); + return -1; + } else if (nread == 0) { + if (chunksize != -1) { + error_msg ("Unable to read all data"); + return -1; + } + + return 0; + } + + nwritten = fwrite (buffer, 1, nread, dst_file); + + if (nwritten != nread) { + if (ferror (dst_file)) + perror_msg ("write"); + else + error_msg ("Unable to write all data"); + return -1; + } + + if (chunksize != -1) + chunksize -= nwritten; + } + + return 0; +} |