/* vi: set sw=4 ts=4: */ /* * Utility routines. * * Copyright (C) many different people. If you wrote this, please * 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 */ #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; }