kernel/utility.c

   1 /* This file contains a collection of miscellaneous procedures:
   2  *   panic:    abort MINIX due to a fatal error
   3  *   kputc:          buffered putc used by kernel printf
   4  */
   5
   6 #include "kernel.h"
   7 #include "proc.h"
   8
   9 #include <minix/syslib.h>
  10 #include <unistd.h>
  11 #include <stdarg.h>
  12 #include <signal.h>
  13
  14 #include <minix/sys_config.h>
  15
  16 #define ARE_PANICING 0xDEADC0FF
  17
  18 /*===========================================================================*
  19  *                      panic                                          *
  20  *===========================================================================*/
  21 PUBLIC void panic(const char *fmt, ...)
  22 {
  23   va_list arg;
  24   /* The system has run aground of a fatal kernel error. Terminate execution. */
  25   if (minix_panicing == ARE_PANICING) {
  26         arch_monitor();
  27   }
  28   minix_panicing = ARE_PANICING;
  29   if (fmt != NULL) {
  30         printf("kernel panic: ");
  31         va_start(arg, fmt);
  32         vprintf(fmt, arg);
  33         printf("\n");
  34   }
  35
  36   printf("kernel: ");
  37   util_stacktrace();
  38
  39   /* Abort MINIX. */
  40   minix_shutdown(NULL);
  41 }
  42
  43 /*===========================================================================*
  44  *                              kputc                                        *
  45  *===========================================================================*/
  46 PUBLIC void kputc(c)
  47 int c;                                  /* character to append */
  48 {
  49 /* Accumulate a single character for a kernel message. Send a notification
  50  * to the output driver if an END_OF_KMESS is encountered.
  51  */
  52   if (c != END_OF_KMESS) {
  53       if (do_serial_debug) {
  54         if(c == '\n')
  55                 ser_putc('\r');
  56         ser_putc(c);
  57       }
  58       kmess.km_buf[kmess.km_next] = c;  /* put normal char in buffer */
  59       if (kmess.km_size < sizeof(kmess.km_buf))
  60           kmess.km_size += 1;
  61       kmess.km_next = (kmess.km_next + 1) % _KMESS_BUF_SIZE;
  62   } else {
  63       int p, outprocs[] = OUTPUT_PROCS_ARRAY;
  64       if(!(minix_panicing || do_serial_debug)) {
  65               for(p = 0; outprocs[p] != NONE; p++) {
  66                  if(isokprocn(outprocs[p]) && !isemptyn(outprocs[p])) {
  67             send_sig(outprocs[p], SIGKMESS);
  68                  }
  69         }
  70      }
  71   }
  72   return;
  73 }