kernel/lib/stdio/read.c

   1 /*
   2  *  ZeX/OS
   3  *  Copyright (C) 2007  Tomas 'ZeXx86' Jedrzejek (zexx86@gmail.com)
   4  *  Copyright (C) 2008  Tomas 'ZeXx86' Jedrzejek (zexx86@gmail.com)
   5  *  Copyright (C) 2009  Tomas 'ZeXx86' Jedrzejek (zexx86@gmail.com)
   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 3 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
  15  *  GNU 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, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21
  22 #include <system.h>
  23 #include <string.h>
  24 #include <file.h>
  25 #include <dev.h>
  26 #include <fd.h>
  27
  28 int read (unsigned fd, void *buf, unsigned len)
  29 {
  30         fd_t *d = fd_get (fd);
  31
  32         if (!d)
  33                 return 0;
  34
  35         if (len > d->e)
  36                 len = d->e;
  37
  38         memcpy ((char *) buf, d->s+d->p, len);
  39 //      memset ((char *) buf+len, 0, 1);
  40
  41         d->e -= len;
  42         d->p += len;
  43
  44         /* HACK: this should call UPDATE handler */
  45         if (d->dev)
  46                 d->dev->handler (DEV_ACT_UPDATE);
  47
  48         return len;
  49 }
  50
  51