#define MINICORO_IMPL

#include "minicoro.h"

#include <assert.h>

#include <string.h>

#include <setjmp.h>

mco_coro* mco_coro_init(void (*effectful_fn)(mco_coro* co), void* user_data) {

mco_coro* co;

mco_desc desc = mco_desc_init(effectful_fn, 0);

desc.user_data = user_data;

mco_result res = mco_create(&co, &desc);

assert(res == MCO_SUCCESS);

return co;

}

void* mco_coro_get_user_data(mco_coro* k) {

return mco_get_user_data(k);

}

char mco_coro_free(mco_coro* k) {

mco_result res = mco_destroy(k);

assert(res == MCO_SUCCESS);

// Ante's Cranelift codegen currently doesn't filter out Unit values.

// So since this function (and other void-returning functions) are thought

// to return unit values we still need to return one here.

return 0;

}

char mco_coro_is_suspended(mco_coro* k) {

return mco_status(k) == MCO_SUSPENDED;

}

char mco_coro_push(mco_coro* k, const void* arg, size_t size) {

mco_result res = mco_push(k, arg, size);

assert(res == MCO_SUCCESS);

return 0;

}

char mco_coro_pop(mco_coro* k, void* arg, size_t size) {

mco_result res = mco_pop(k, arg, size);

assert(res == MCO_SUCCESS);

return 0;

}

char mco_coro_suspend(mco_coro* k) {

mco_result res = mco_yield(k);

assert(res == MCO_SUCCESS);

return 0;

}

char mco_coro_resume(mco_coro* k) {

mco_result res = mco_resume(k);

assert(res == MCO_SUCCESS);

return 0;

}

mco_coro* mco_coro_running(void) {

return mco_running();

}

size_t mco_coro_bytes_stored(mco_coro* k) {

return mco_get_bytes_stored(k);

}

// Bulk-move `len` bytes from `src`'s storage to `dst`'s storage, preserving

// byte order. Used by the effect-lowering pass to forward an effect through a

// nested handler's drive without parsing the args by type.

char mco_coro_transfer(mco_coro* src, mco_coro* dst, size_t len) {

if (len == 0) return 0;

assert(src != NULL && dst != NULL);

assert(len <= src->bytes_stored);

assert(dst->bytes_stored + len <= dst->storage_size);

memcpy(&dst->storage[dst->bytes_stored],

&src->storage[src->bytes_stored - len],

len);

dst->bytes_stored += len;

src->bytes_stored -= len;

return 0;

}

// Not a coroutine function but used by Fail/Throw-like effects.

//

// Calls `body(env)` in a context where any wrapper that calls

// `mco_abort_longjmp(buf, val)` will unwind back to this call and

// `mco_abort_call` will return `val`. Returns 0 if body completes normally.

//

// `buf` must point to at least `sizeof(jmp_buf)` bytes.

int mco_abort_call(void* buf, void (*body)(void* env), void* env) {

int v = setjmp(*(jmp_buf*)buf);

if (v == 0) {

body(env);

return 0;

}

return v;

}

// Unwind back to the matching `mco_abort_call`, setting its return value to

// `val`. Never returns.

void mco_abort_longjmp(void* buf, int val) {

longjmp(*(jmp_buf*)buf, val);

}