package/base/sysfiles/btee.c

   1 /*
   2  * --- T2-COPYRIGHT-NOTE-BEGIN ---
   3  * This copyright note is auto-generated by ./scripts/Create-CopyPatch.
   4  *
   5  * T2 SDE: package/.../sysfiles/btee.c
   6  * Copyright (C) 2004 - 2005 The T2 SDE Project
   7  *
   8  * More information can be found in the files COPYING and README.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; version 2 of the License. A copy of the
  13  * GNU General Public License can be found in the file COPYING.
  14  * --- T2-COPYRIGHT-NOTE-END ---
  15  */
  16 /*  btee.c, a buffered tee clone   -   written for ROCK Linux
  17
  18     Copyright (C) 1998, 1999, 2001, 2003  Clifford Wolf
  19
  20     This program is free software; you can redistribute it and/or modify
  21     it under the terms of the GNU General Public License as published by
  22     the Free Software Foundation; either version 2 of the License, or
  23     (at your option) any later version.
  24
  25     This program is distributed in the hope that it will be useful,
  26     but WITHOUT ANY WARRANTY; without even the implied warranty of
  27     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  28     GNU General Public License for more details.
  29
  30     You should have received a copy of the GNU General Public License
  31     along with this program; if not, write to the Free Software
  32     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  33 */
  34
  35 #define _GNU_SOURCE
  36
  37 #include <stdio.h>
  38 #include <unistd.h>
  39 #include <sys/types.h>
  40 #include <sys/stat.h>
  41 #include <signal.h>
  42 #include <stdlib.h>
  43 #include <fcntl.h>
  44
  45 #define BUFFER_SIZE (8*1024-1)
  46 static char buffer[BUFFER_SIZE+1];
  47
  48 #define EOT 004
  49
  50 void exit_handler(int sig) {
  51         exit(1);
  52 }
  53
  54 int main(int argc, char ** argv) {
  55         int rc, mode, x, y;
  56         int remove_zeros=0;
  57         int pos=0, killme=0;
  58
  59         if ( argc!=3 || (argv[1][0]!='a' && argv[1][0]!='t') ) {
  60                 printf("Usage: %s {a|t} [file]\n",argv[0]);
  61                 return 1;
  62         }
  63
  64         if (argv[1][0]=='a')
  65                 mode=O_WRONLY|O_CREAT|O_APPEND;
  66         else
  67                 mode=O_WRONLY|O_CREAT|O_TRUNC;
  68
  69         signal(SIGALRM, exit_handler);
  70
  71         while (1) {
  72                 if (killme == 1) {
  73                         killme = -1;
  74                         alarm(3);
  75                 }
  76
  77                 if (pos >= BUFFER_SIZE) {
  78                         fprintf(stderr, "%s: Buffer is full -> "
  79                                 "drop data!\n",argv[0]);
  80                         pos=0;
  81                 }
  82
  83                 rc=read(0,buffer+pos,BUFFER_SIZE-pos);
  84                 if (rc <= 0) return 0;
  85                 buffer[pos+rc+1]=0;
  86
  87                 if (rc>0) {
  88                         for (x=0; x<rc; x++) {
  89                                 if ( buffer[pos+x] != EOT )
  90                                         write(1,buffer+pos+x,1);
  91                         }
  92
  93                         for (x=0; x<rc; x++) {
  94                                 if (buffer[pos+x]==EOT) {
  95                                         /* We wait a few seconds so we are
  96                                          * still able to pipe thru 'early
  97                                          * errors' from daemons. */
  98                                         buffer[pos+x]=0;
  99                                         if (!killme) killme = 1;
 100                                         remove_zeros=1;
 101                                 }
 102                                 if (buffer[pos+x]=='\r' &&
 103                                     buffer[pos+x+1]!='\n') {
 104                                         for (y=pos+x; y>=0; y--) {
 105                                                 if (buffer[y]=='\n') break;
 106                                                 buffer[y]=0;
 107                                         }
 108                                         remove_zeros=1;
 109                                 }
 110                         }
 111
 112                         pos+=rc;
 113
 114                         if (remove_zeros) {
 115                                 for (x=y=0; x<pos; x++) {
 116                                         if (buffer[x])
 117                                                 buffer[y++]=buffer[x];
 118                                 }
 119                                 pos=y; remove_zeros=0;
 120                         }
 121
 122                         rc=open(argv[2],mode,0666);
 123                         if (rc>=0) {
 124                                 write(rc,buffer,pos);
 125                                 close(rc);
 126                                 pos=0;
 127                                 mode=O_WRONLY|O_APPEND;
 128                         }
 129                 }
 130         }
 131
 132         return 0;
 133 }