mirror of
https://github.com/raphnet/gc_n64_usb-v3
synced 2024-08-13 17:03:49 -04:00
b22985712f
If the stack ever grows too large (and starts overwriting variables in .bss) the firmware jumps into the bootloader. This is better than just continuing to run with strange side effects.
61 lines
1.1 KiB
C
61 lines
1.1 KiB
C
#include <stdio.h>
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#include <stdint.h>
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#include <avr/io.h>
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#include <util/atomic.h>
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#include "stkchk.h"
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extern uint16_t __stack;
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extern uint16_t _end;
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/** Write a canary at the end of the stack. */
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void stkchk_init(void)
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{
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*((&_end)-1) = 0xDEAD;
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}
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/** Check if the canary is still alive.
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*
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* Call this perdiocally to check if the
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* stack grew too large.
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**/
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char stkchk_verify(void)
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{
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if (*((&_end)-1) != 0xDEAD) {
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return -1;
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}
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return 0;
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}
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/* In order to get an approximate idea of how
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* much stack you are using, this can be called
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* at strategic places where you know the
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* call stack is deep or where large automatic
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* buffers are used.
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*/
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#ifdef STKCHK_WITH_STATUS_CHECK
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void stkchk(const char *fname)
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{
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static int max_usage = 0;
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uint16_t end = ((uint16_t)&_end);
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uint16_t s_top = ((uint16_t)&__stack);
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uint16_t s_cur = SPL | SPH<<8;
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uint16_t used, s_size;
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uint8_t grew = 0;
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ATOMIC_BLOCK(ATOMIC_RESTORESTATE)
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{
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used = s_top - s_cur;
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s_size = s_top - end;
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if (used > max_usage) {
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max_usage = used;
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grew = 1;
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}
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}
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if (grew) {
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printf("[stkchk] %s: %d/%d\r\n", fname, used, s_size);
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}
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}
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#endif
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