#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/mman.h>
#include <semaphore.h>
#include "elfcalls.h"
#include "threads.h"

static void* dlopen_simple(const char* name)
{
	return dlopen(name, RTLD_LAZY);
}

static void* dlopen_fatal(const char* name)
{
	void* rv = dlopen_simple(name);
	if (!rv)
	{
		fprintf(stderr, "Cannot load %s (ELF): %s\n", name, dlerror());
		abort();
	}
	return rv;
}

static void* dlsym_fatal(void* handle, const char* sym)
{
	void* addr = dlsym(handle, sym);
	if (!addr)
	{
		fprintf(stderr, "Failed to lookup symbol %s (ELF): %s\n", sym, dlerror());
		abort();
	}
	return addr;
}

static int dlclose_fatal(void* handle)
{
	if (dlclose(handle) != 0)
	{
		fprintf(stderr, "Cannot dlclose library (ELF): %s\n", dlerror());
		abort();
	}
	return 0;
}

static int get_errno(void)
{
	return errno;
}

void elfcalls_make(struct elf_calls* calls)
{
	calls->dlopen = dlopen_simple;
	calls->dlclose = dlclose;
	calls->dlsym = dlsym;
	calls->dlerror = dlerror;

	calls->dlopen_fatal = dlopen_fatal;
	calls->dlsym_fatal = dlsym_fatal;
	calls->dlclose_fatal = dlclose_fatal;

	calls->darling_thread_create = __darling_thread_create;
	calls->darling_thread_terminate = __darling_thread_terminate;
	calls->darling_thread_get_stack = __darling_thread_get_stack;

	calls->get_errno = get_errno;
	calls->exit = exit;
	*((void**)&calls->sem_open) = sem_open;
	*((void**)&calls->sem_wait) = sem_wait;
	*((void**)&calls->sem_trywait) = sem_trywait;
	*((void**)&calls->sem_post) = sem_post;
	*((void**)&calls->sem_close) = sem_close;
	*((void**)&calls->sem_unlink) = sem_unlink;

	*((void**)&calls->shm_open) = shm_open;
	*((void**)&calls->shm_unlink) = shm_unlink;
}

int main(int argc, const char** argv)
{
	typedef void (*retfunc)(void);

	struct elf_calls* calls;
	retfunc ret;

	// for (int i = 0; i < argc; i++)
	// 	printf("arg %d: %s\n", i, argv[i]);

	calls = (struct elf_calls*) strtoul(argv[1], NULL, 16);
	ret = (retfunc) strtoul(argv[2], NULL, 16);

	// puts("before elfcalls_make");

	elfcalls_make(calls);
	// puts("after elfcalls_make");
	// printf("Will call %p\n", ret);
	ret();

	__builtin_unreachable();
}