kernel/trace.c

   1 /*
   2  *    Copyright (c) 2009 Joshua Phillips. All rights reserved.
   3  *
   4  *  Redistribution and use in source and binary forms, with or without
   5  *  modification, are permitted provided that the following conditions are
   6  *  met:
   7  *
   8  *    1. Redistributions of source code must retain the above copyright
   9  *       notice, this list of conditions and the following disclaimer.
  10  *    2. Redistributions in binary form must reproduce the above copyright
  11  *       notice, this list of conditions and the following disclaimer in
  12  *       the documentation and/or other materials provided with the
  13  *       distribution.
  14  *
  15  *  THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
  16  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  18  *  DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
  19  *  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  *  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  21  *  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  22  *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  23  *  IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  *  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
  25  *  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 /*
  29  *   The TRACE macro provides simple debugging output, either to the
  30  *   serial port or vgatext.
  31  */
  32
  33 #include "trace.h"
  34 #include "serial.h"
  35 #include "console.h"
  36 #include "stdio.h"
  37 #include "string.h"
  38 #include "portio.h"
  39
  40 // Use a hack in Bochs - repeatedly output to port 0xE9
  41 // On real hardware, 0xE9 is unused, so it does nothing
  42
  43 static void bochs_e9_hack(const char *str)
  44 {
  45     while (*str){
  46         outb(0xE9, *str);
  47         ++str;
  48     }
  49 }
  50
  51 void trace_internal(const char *file, int line, const char *func, const char *fmt, ...)
  52 {
  53     char str[256], *short_str, *actual_msg, c;
  54     int len;
  55     va_list ap;
  56
  57     // file:line: (function): message
  58     // ^str       ^short_str  ^actual_msg
  59
  60     va_start(ap, fmt);
  61
  62     len = snprintf(str, 256, "%s:%d: ", file, line);
  63     short_str = str + len;
  64     len += snprintf(str + len, 256 - len, "(%s): ", func);
  65     actual_msg = str + len;
  66     len += vsnprintf(str + len, 256 - len, fmt, ap);
  67     strncat(str + len, "\n", 256 - len);
  68     str[255] = '\0';
  69     if (serial_is_initialized(&com1)){
  70         serial_send(&com1, str);
  71     }
  72     bochs_e9_hack(str);
  73
  74     // print "(function): message" to console
  75     // with colours
  76     c = *actual_msg;
  77     *actual_msg = '\0';
  78     console_colour_fg(&tty1, COLOUR_BRIGHT_WHITE);
  79     console_puts(&tty1, short_str);
  80     console_colour_default(&tty1);
  81     *actual_msg = c;
  82     console_puts(&tty1, actual_msg);
  83
  84     va_end(ap);
  85 }