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      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 };
     85