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#include <string.h>
#include <stdint.h>
#if defined(__wasilibc_unmodified_upstream) || defined(_REENTRANT)
#include "pthread_impl.h"
#else
// In non-_REENTRANT, include it for `a_crash`
# include "atomic.h"
#endif
uintptr_t __stack_chk_guard;
void __init_ssp(void *entropy)
{
if (entropy) memcpy(&__stack_chk_guard, entropy, sizeof(uintptr_t));
else __stack_chk_guard = (uintptr_t)&__stack_chk_guard * 1103515245;
#if UINTPTR_MAX >= 0xffffffffffffffff
/* Sacrifice 8 bits of entropy on 64bit to prevent leaking/
* overwriting the canary via string-manipulation functions.
* The NULL byte is on the second byte so that off-by-ones can
* still be detected. Endianness is taken care of
* automatically. */
((char *)&__stack_chk_guard)[1] = 0;
#endif
#if defined(__wasilibc_unmodified_upstream) || defined(_REENTRANT)
__pthread_self()->canary = __stack_chk_guard;
#endif
}
void __stack_chk_fail(void)
{
a_crash();
}
hidden void __stack_chk_fail_local(void);
weak_alias(__stack_chk_fail, __stack_chk_fail_local);
#ifndef __wasilibc_unmodified_upstream
# include <wasi/api.h>
__attribute__((constructor(60)))
static void __wasilibc_init_ssp(void) {
uintptr_t entropy;
int r = __wasi_random_get((uint8_t *)&entropy, sizeof(uintptr_t));
__init_ssp(r ? NULL : &entropy);
}
#endif
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