minix/kernel/misc.c
Jorrit Herder ccd17ecfed New NOTIFY system call! Queued at kernel. Duplicate messages (with same source
and type) are overwritten with newer flags/ arguments. The interface from
within the kernel is lock_notify(). User processes can make a system call with
notify(). NOTIFY fully replaces the old notification mechanism.
2005-05-24 10:06:17 +00:00

145 lines
4.1 KiB
C
Executable file

/* This file contains a collection of miscellaneous procedures:
* panic abort MINIX due to a fatal error
* bad_assertion for debugging
* bad_compare for debugging
* alloc_bit bit map manipulation
* free_bit bit map manipulation
* print_bitmap bit map manipulation
*/
#include "kernel.h"
#include "assert.h"
#include <unistd.h>
#include <minix/com.h>
/*===========================================================================*
* panic *
*===========================================================================*/
PUBLIC void panic(s,n)
_CONST char *s;
int n;
{
/* The system has run aground of a fatal error. Terminate execution.
* If the panic originated in MM or FS, the string will be empty and the
* file system already syncked. If the panic originates in the kernel, we are
* kind of stuck.
*/
static int panicking = 0;
if (panicking ++) /* prevent recursive panics */
return;
if (s != NULL) {
kprintf("\nKernel panic: %s", karg(s));
if (n != NO_NUM) kprintf(" %d", n);
kprintf("\n",NO_ARG);
}
prepare_shutdown(RBT_PANIC);
}
/*===========================================================================*
* print_bitmap *
*===========================================================================*/
PUBLIC void print_bitmap(bitmap, nr_bits)
bitchunk_t *bitmap;
bit_t nr_bits;
{
bit_t bit_i;
for (bit_i=0; bit_i < nr_bits; bit_i++) {
kprintf("%d", GET_BIT(bitmap, bit_i) > 0 );
if (! ((bit_i+1) % 8) ) kprintf(" ", NO_ARG);
if (! ((bit_i+1) % 64) ) kprintf("\n", NO_ARG);
}
kprintf("\n", NO_ARG);
}
/*===========================================================================*
* free_bit *
*===========================================================================*/
PUBLIC void free_bit(bit_nr, bitmap, nr_bits)
bit_t bit_nr;
bitchunk_t *bitmap;
bit_t nr_bits;
{
bitchunk_t *chunk;
if (bit_nr >= nr_bits) {
kprintf("Warning, free_bit: %d illegal index\n", bit_nr);
return;
}
chunk = &bitmap[(bit_nr/BITCHUNK_BITS)];
*chunk &= ~(1 << (bit_nr % BITCHUNK_BITS));
}
/*===========================================================================*
* alloc_bit *
*===========================================================================*/
PUBLIC int alloc_bit(bitmap, nr_bits)
bitchunk_t *bitmap;
bit_t nr_bits;
{
bitchunk_t *chunk;
int nr_chunks;
int bit_nr;
int i;
/* Iterate over the words in block. */
nr_chunks = BITMAP_CHUNKS(nr_bits);
for (chunk = &bitmap[0]; chunk < &bitmap[nr_chunks]; chunk++) {
/* Does this chunk contain a free bit? */
if (*chunk == (bitchunk_t) ~0) continue;
/* Get bit number from the start of the bit map. */
for (i = 0; (*chunk & (1 << i)) != 0; ++i) {}
bit_nr = (chunk - &bitmap[0]) * BITCHUNK_BITS + i;
/* Don't allocate bits beyond the end of the map. */
if (bit_nr >= nr_bits) break;
*chunk |= 1 << bit_nr % BITCHUNK_BITS;
return(bit_nr);
}
kprintf("Warning, all %d bits in map busy\n", nr_bits);
return(-1);
}
#if !NDEBUG
/*=========================================================================*
* bad_assertion *
*=========================================================================*/
PUBLIC void bad_assertion(file, line, what)
char *file;
int line;
char *what;
{
kprintf("panic at %s", karg(file));
kprintf(" (line %d): ", line);
kprintf("assertion \"%s\" failed.\n", karg(what));
panic(NULL, NO_NUM);
}
/*=========================================================================*
* bad_compare *
*=========================================================================*/
PUBLIC void bad_compare(file, line, lhs, what, rhs)
char *file;
int line;
int lhs;
char *what;
int rhs;
{
kprintf("panic at %s", karg(file));
kprintf(" (line %d): ", line);
kprintf("compare (%d)", lhs);
kprintf(" %s ", karg(what));
kprintf("(%d) failed.\n", rhs);
panic(NULL, NO_NUM);
}
#endif /* !NDEBUG */