1/* vi: set sw=4 ts=4: */ 2/* 3 * Utility routines. 4 * 5 * Copyright (C) tons of folks. Tracking down who wrote what 6 * isn't something I'm going to worry about... If you wrote something 7 * here, please feel free to acknowledge your work. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 22 * 23 * Based in part on code from sash, Copyright (c) 1999 by David I. Bell 24 * Permission has been granted to redistribute this code under the GPL. 25 * 26 */ 27 28#include <stdio.h> 29#include <sys/stat.h> 30#include "libbb.h" 31 32/* Copy CHUNKSIZE bytes (or until EOF if CHUNKSIZE equals -1) from SRC_FILE 33 * to DST_FILE. */ 34extern int copy_file_chunk(FILE *src_file, FILE *dst_file, unsigned long long chunksize) 35{ 36 size_t nread, nwritten, size; 37 char buffer[BUFSIZ]; 38 39 while (chunksize != 0) { 40 if (chunksize > BUFSIZ) 41 size = BUFSIZ; 42 else 43 size = chunksize; 44 45 nread = fread (buffer, 1, size, src_file); 46 47 if (nread != size && ferror (src_file)) { 48 perror_msg ("read"); 49 return -1; 50 } else if (nread == 0) { 51 if (chunksize != -1) { 52 error_msg ("Unable to read all data"); 53 return -1; 54 } 55 56 return 0; 57 } 58 59 nwritten = fwrite (buffer, 1, nread, dst_file); 60 61 if (nwritten != nread) { 62 if (ferror (dst_file)) 63 perror_msg ("write"); 64 else 65 error_msg ("Unable to write all data"); 66 return -1; 67 } 68 69 if (chunksize != -1) 70 chunksize -= nwritten; 71 } 72 73 return 0; 74} 75