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#include "substitute-internal.h"
#include "execmem.h"
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <pthread.h>
#include <assert.h>
/* printf without taking any locks - because they might be taken at stop time */
#define ulprintf(...) do { \
char buf[256]; \
int len = sprintf(buf, __VA_ARGS__); \
write(1, buf, len); \
} while(0)
static void *some_thread(void *ip) {
long i = (long) ip;
while (1) {
ulprintf("Hello from %ld\n", i);
sleep(1);
}
}
static void replacement() {
ulprintf("Bye\n");
pthread_exit(NULL);
}
static uintptr_t patch_callback(void *ctx, UNUSED uintptr_t pc) {
assert(!ctx);
return (uintptr_t) replacement;
}
int main() {
pthread_t pts[10];
for (long i = 0; i < 10; i++)
pthread_create(&pts[i], NULL, some_thread, (void *) i);
sleep(1);
char *foo = malloc(0x10000);
static char bar[16];
struct execmem_foreign_write writes[] = {
{foo, bar, 5},
{foo + 7, bar + 7, 3},
};
int ret = execmem_foreign_write_with_pc_patch(writes,
sizeof(writes)/sizeof(*writes),
patch_callback,
NULL);
ulprintf("==> %d\n", ret);
void *out;
for (long i = 0; i < 10; i++)
assert(!pthread_join(pts[i], &out));
}
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