THREAD_FUNC(print_hello, param) {
context_t* ctx = param;
for (;;) {
SLEEP(rand() % 5);
printf("%d is hungry!\n", ctx->id);
if (ctx->id % 2) {
// Pick Up Right Before Left
if (MUTEX_TRYLOCK(*ctx->right_chopstick)) {
printf("%d got right chopstick\n", ctx->id);
} else {
printf("%d couldn't get right chopstick, will try later\n", ctx->id);
continue;
}
if (MUTEX_TRYLOCK(*ctx->left_chopstick)) {
printf("%d got left chopstick\n", ctx->id);
} else {
printf("%d couldn't get left chopstick, will try later\n", ctx->id);
MUTEX_UNLOCK(*ctx->right_chopstick);
printf("%d release right chopstick\n", ctx->id);
continue;
}
} else {
// Pick Up Left Before Right
if (MUTEX_TRYLOCK(*ctx->left_chopstick)) {
printf("%d got left chopstick\n", ctx->id);
} else {
printf("%d couldn't get left chopstick, will try later\n", ctx->id);
continue;
}
if (MUTEX_TRYLOCK(*ctx->right_chopstick)) {
printf("%d got right chopstick\n", ctx->id);
} else {
printf("%d couldn't get right chopstick, will try later\n", ctx->id);
MUTEX_UNLOCK(*ctx->left_chopstick);
printf("%d release left chopstick\n", ctx->id);
continue;
}
}
printf("%d start eating\n", ctx->id);
SLEEP(1);
printf("%d finish eating\n", ctx->id);
MUTEX_UNLOCK(*ctx->right_chopstick);
printf("%d release right chopstick\n", ctx->id);
MUTEX_UNLOCK(*ctx->left_chopstick);
printf("%d release left chopstick\n", ctx->id);
}
free(ctx);
return 0;
}
ConnMgr::status_t ConnMgr::trylock()
{
int rc = MUTEX_TRYLOCK(&mapMutex);
if (rc == 0)
return SUCCESS;
if (rc == EDEADLK)
return ERR_LOCK_AOWNED;
if (rc == EBUSY)
return ERR_LOCK_BUSY;
return ERR_LOCK;
}
