libc/stdio/fgets.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2009  Tomas 'ZeXx86' Jedrzejek (zexx86@gmail.com)
   4  *
   5  *  This program is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19
  20 #include <errno.h>
  21 #include <stdio.h>
  22 #include <fcntl.h>
  23 #include <stdlib.h>
  24
  25 char *fgets (char *s, int size, FILE *stream)
  26 {
  27         if (!stream || !s || size < 2)
  28                 goto err;
  29
  30         if (stream->mode & O_WRONLY)
  31                 goto err;
  32
  33         int i;
  34         for (i = 0; i < (size-1); i ++) {
  35                 int r = fgetc (stream);
  36
  37                 if (!r)
  38                         break;
  39
  40                 s[i] = r;
  41
  42                 if (r == '\n')
  43                         break;
  44         }
  45
  46         s[i+1] = '\0';
  47
  48         if (!i)
  49                 goto err;
  50
  51         stream->off += i;
  52
  53         return s;
  54 err:
  55         errno_update ();
  56
  57         return 0;
  58 }