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#define _GNU_SOURCE
#include "../include/config.h"
#include "../include/ld_rtld.h"
#include <dlfcn.h>
#include <gnu/lib-names.h>
#include <gnu/libc-version.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#define WARN(format, ...) fprintf(stderr, "ulp: " format "\n", ##__VA_ARGS__)
#define libpulp_errx(a, ...) fprintf(stderr, __VA_ARGS__); abort();
void __attribute__((noreturn))
libpulp_crash(const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
vfprintf(stderr, fmt, args);
va_end (args);
abort();
}
static volatile pthread_mutex_t *dl_load_lock = NULL;
static volatile pthread_mutex_t *dl_load_write_lock = NULL;
#include "../lib/symbol_loader.c"
static volatile int gate = 0;
void *
observer(void *args __attribute__((unused)))
{
while (1) {
int lock = dl_load_lock->__data.__lock;
if (lock == 1) {
printf("dl lock was acquired: %d\n", lock);
gate = 1;
return (void *)0;
}
else if (lock < 0 || lock > 1) {
printf("dl lock is nonsensical: %d\n", lock);
return (void *)1;
}
}
return (void *)1;
}
void *
dlsym_poke(void *args __attribute__((unused)))
{
while (!gate) {
dlsym(RTLD_DEFAULT, "malloc");
}
return NULL;
}
int
main()
{
unsigned long observer_ret;
get_ld_global_locks((void *) &dl_load_lock, (void *) &dl_load_write_lock);
pthread_t observer_thread, dlsym_thread;
pthread_create(&observer_thread, NULL, observer, NULL);
pthread_create(&dlsym_thread, NULL, dlsym_poke, NULL);
pthread_join(observer_thread, (void *)&observer_ret);
pthread_join(dlsym_thread, NULL);
return (int)observer_ret;
}
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