com32/lib/sys/stdcon_write.c

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2004-2008 H. Peter Anvin - All Rights Reserved
   4  *
   5  *   Permission is hereby granted, free of charge, to any person
   6  *   obtaining a copy of this software and associated documentation
   7  *   files (the "Software"), to deal in the Software without
   8  *   restriction, including without limitation the rights to use,
   9  *   copy, modify, merge, publish, distribute, sublicense, and/or
  10  *   sell copies of the Software, and to permit persons to whom
  11  *   the Software is furnished to do so, subject to the following
  12  *   conditions:
  13  *
  14  *   The above copyright notice and this permission notice shall
  15  *   be included in all copies or substantial portions of the Software.
  16  *
  17  *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  19  *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  20  *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  21  *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  22  *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  24  *   OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  * ----------------------------------------------------------------------- */
  27
  28 /*
  29  * stdcon_write.c
  30  *
  31  * Writing to the console; \n -> \r\n conversion.
  32  */
  33
  34 #include <errno.h>
  35 #include <string.h>
  36 #include <com32.h>
  37 #include <core.h>
  38 #include <minmax.h>
  39 #include "file.h"
  40
  41 #define BIOS_ROWS (*(uint8_t *)0x484)   /* Minus one; if zero use 24 (= 25 lines) */
  42 #define BIOS_COLS (*(uint16_t *)0x44A)
  43
  44 static int __stdcon_open(struct file_info *fp)
  45 {
  46     fp->o.rows = BIOS_ROWS + 1;
  47     fp->o.cols = BIOS_COLS;
  48
  49     /* Sanity check */
  50     if (fp->o.rows < 12)
  51         fp->o.rows = 24;
  52     if (fp->o.cols < 40)
  53         fp->o.cols = 80;
  54
  55     return 0;
  56 }
  57
  58 static ssize_t __stdcon_write(struct file_info *fp, const void *buf,
  59                               size_t count)
  60 {
  61     const char *bufp = buf;
  62     size_t n = 0;
  63
  64     (void)fp;
  65
  66     while (count--) {
  67         if (*bufp == '\n')
  68             writechr('\r');
  69
  70         writechr(*bufp++);
  71         n++;
  72     }
  73
  74     return n;
  75 }
  76
  77 const struct output_dev dev_stdcon_w = {
  78     .dev_magic = __DEV_MAGIC,
  79     .flags = __DEV_TTY | __DEV_OUTPUT,
  80     .fileflags = O_WRONLY | O_CREAT | O_TRUNC | O_APPEND,
  81     .write = __stdcon_write,
  82     .close = NULL,
  83     .open  = __stdcon_open,
  84 };