libbb/copyfd.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Utility routines.
   4  *
   5  * Copyright (C) 1999-2001 Erik Andersen <andersee@debian.org>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  */
  21
  22 #include <unistd.h>
  23 #include <string.h>
  24 #include <errno.h>
  25 #include "libbb.h"
  26
  27
  28 extern size_t copyfd(int fd1, int fd2)
  29 {
  30         char buf[32768], *writebuf;
  31         int status = TRUE;
  32         size_t totalread = 0, bytesread, byteswritten;
  33
  34         while(status) {
  35                 bytesread = read(fd1, &buf, sizeof(buf));
  36                 if(bytesread == -1) {
  37                         error_msg("read: %s", strerror(errno));
  38                         status = FALSE;
  39                         break;
  40                 }
  41                 byteswritten = 0;
  42                 writebuf = buf;
  43                 while(bytesread) {
  44                         byteswritten = write( fd2, &writebuf, bytesread );
  45                         if(byteswritten == -1) {
  46                                 error_msg("write: %s", strerror(errno));
  47                                 status = FALSE;
  48                                 break;
  49                         }
  50                         bytesread -= byteswritten;
  51                         writebuf += byteswritten;
  52                 }
  53         }
  54         if ( status == TRUE )
  55                 return totalread;
  56         else
  57                 return -1;
  58 }
  59
  60 /* END CODE */
  61 /*
  62 Local Variables:
  63 c-file-style: "linux"
  64 c-basic-offset: 4
  65 tab-width: 4
  66 End:
  67 */