/*

* This file is part of the MicroPython project, http://micropython.org/

*

* The MIT License (MIT)

*

* SPDX-FileCopyrightText: Copyright (c) 2016 Damien P. George on behalf of Pycom Ltd

*

* Permission is hereby granted, free of charge, to any person obtaining a copy

* of this software and associated documentation files (the "Software"), to deal

* in the Software without restriction, including without limitation the rights

* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

* copies of the Software, and to permit persons to whom the Software is

* furnished to do so, subject to the following conditions:

*

* The above copyright notice and this permission notice shall be included in

* all copies or substantial portions of the Software.

*

* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

* THE SOFTWARE.

*/

#include <stdio.h>

#include <string.h>

#include "py/runtime.h"

#include "py/stackctrl.h"

#include "supervisor/shared/translate.h"

#if MICROPY_PY_THREAD

#include "py/mpthread.h"

#if MICROPY_DEBUG_VERBOSE // print debugging info

#define DEBUG_PRINT (1)

#define DEBUG_printf DEBUG_printf

#else // don't print debugging info

#define DEBUG_PRINT (0)

#define DEBUG_printf(...) (void)0

#endif

/****************************************************************/

// Lock object

STATIC const mp_obj_type_t mp_type_thread_lock;

typedef struct _mp_obj_thread_lock_t {

mp_obj_base_t base;

mp_thread_mutex_t mutex;

volatile bool locked;

} mp_obj_thread_lock_t;

STATIC mp_obj_thread_lock_t *mp_obj_new_thread_lock(void) {

mp_obj_thread_lock_t *self = m_new_obj(mp_obj_thread_lock_t);

self->base.type = &mp_type_thread_lock;

mp_thread_mutex_init(&self->mutex);

self->locked = false;

return self;

}

STATIC mp_obj_t thread_lock_acquire(size_t n_args, const mp_obj_t *args) {

mp_obj_thread_lock_t *self = MP_OBJ_TO_PTR(args[0]);

bool wait = true;

if (n_args > 1) {

wait = mp_obj_get_int(args[1]);

// TODO support timeout arg

}

MP_THREAD_GIL_EXIT();

int ret = mp_thread_mutex_lock(&self->mutex, wait);

MP_THREAD_GIL_ENTER();

if (ret == 0) {

return mp_const_false;

} else if (ret == 1) {

self->locked = true;

return mp_const_true;

} else {

mp_raise_OSError(-ret);

}

}

STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(thread_lock_acquire_obj, 1, 3, thread_lock_acquire);

STATIC mp_obj_t thread_lock_release(mp_obj_t self_in) {

mp_obj_thread_lock_t *self = MP_OBJ_TO_PTR(self_in);

if (!self->locked) {

mp_raise_msg(&mp_type_RuntimeError, NULL);

}

self->locked = false;

MP_THREAD_GIL_EXIT();

mp_thread_mutex_unlock(&self->mutex);

MP_THREAD_GIL_ENTER();

return mp_const_none;

}

STATIC MP_DEFINE_CONST_FUN_OBJ_1(thread_lock_release_obj, thread_lock_release);

STATIC mp_obj_t thread_lock_locked(mp_obj_t self_in) {

mp_obj_thread_lock_t *self = MP_OBJ_TO_PTR(self_in);

return mp_obj_new_bool(self->locked);

}

STATIC MP_DEFINE_CONST_FUN_OBJ_1(thread_lock_locked_obj, thread_lock_locked);

STATIC mp_obj_t thread_lock___exit__(size_t n_args, const mp_obj_t *args) {

(void)n_args; // unused

return thread_lock_release(args[0]);

}

STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(thread_lock___exit___obj, 4, 4, thread_lock___exit__);

STATIC const mp_rom_map_elem_t thread_lock_locals_dict_table[] = {

{ MP_ROM_QSTR(MP_QSTR_acquire), MP_ROM_PTR(&thread_lock_acquire_obj) },

{ MP_ROM_QSTR(MP_QSTR_release), MP_ROM_PTR(&thread_lock_release_obj) },

{ MP_ROM_QSTR(MP_QSTR_locked), MP_ROM_PTR(&thread_lock_locked_obj) },

{ MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&thread_lock_acquire_obj) },

{ MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&thread_lock___exit___obj) },

};

STATIC MP_DEFINE_CONST_DICT(thread_lock_locals_dict, thread_lock_locals_dict_table);

STATIC const mp_obj_type_t mp_type_thread_lock = {

{ &mp_type_type },

.name = MP_QSTR_lock,

.locals_dict = (mp_obj_dict_t *)&thread_lock_locals_dict,

};

/****************************************************************/

// _thread module

STATIC size_t thread_stack_size = 0;

STATIC mp_obj_t mod_thread_get_ident(void) {

return mp_obj_new_int_from_uint((uintptr_t)mp_thread_get_state());

}

STATIC MP_DEFINE_CONST_FUN_OBJ_0(mod_thread_get_ident_obj, mod_thread_get_ident);

STATIC mp_obj_t mod_thread_stack_size(size_t n_args, const mp_obj_t *args) {

mp_obj_t ret = mp_obj_new_int_from_uint(thread_stack_size);

if (n_args == 0) {

thread_stack_size = 0;

} else {

thread_stack_size = mp_obj_get_int(args[0]);

}

return ret;

}

STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_thread_stack_size_obj, 0, 1, mod_thread_stack_size);

typedef struct _thread_entry_args_t {

mp_obj_dict_t *dict_locals;

mp_obj_dict_t *dict_globals;

size_t stack_size;

mp_obj_t fun;

size_t n_args;

size_t n_kw;

mp_obj_t args[];

} thread_entry_args_t;

STATIC void *thread_entry(void *args_in) {

// Execution begins here for a new thread. We do not have the GIL.

thread_entry_args_t *args = (thread_entry_args_t *)args_in;

mp_state_thread_t ts;

mp_thread_set_state(&ts);

mp_stack_set_top(&ts + 1); // need to include ts in root-pointer scan

mp_stack_set_limit(args->stack_size);

#if MICROPY_ENABLE_PYSTACK

// TODO threading and pystack is not fully supported, for now just make a small stack

mp_obj_t mini_pystack[128];

mp_pystack_init(mini_pystack, &mini_pystack[128]);

#endif

// set locals and globals from the calling context

mp_locals_set(args->dict_locals);

mp_globals_set(args->dict_globals);

MP_THREAD_GIL_ENTER();

// signal that we are set up and running

mp_thread_start();

// TODO set more thread-specific state here:

// mp_pending_exception? (root pointer)

// cur_exception (root pointer)

DEBUG_printf("[thread] start ts=%p args=%p stack=%p\n", &ts, &args, MP_STATE_THREAD(stack_top));

nlr_buf_t nlr;

if (nlr_push(&nlr) == 0) {

mp_call_function_n_kw(args->fun, args->n_args, args->n_kw, args->args);

nlr_pop();

} else {

// uncaught exception

// check for SystemExit

mp_obj_base_t *exc = (mp_obj_base_t *)nlr.ret_val;

if (mp_obj_is_subclass_fast(MP_OBJ_FROM_PTR(exc->type), MP_OBJ_FROM_PTR(&mp_type_SystemExit))) {

// swallow exception silently

} else {

// print exception out

mp_printf(MICROPY_ERROR_PRINTER, "Unhandled exception in thread started by ");

mp_obj_print_helper(MICROPY_ERROR_PRINTER, args->fun, PRINT_REPR);

mp_printf(MICROPY_ERROR_PRINTER, "\n");

mp_obj_print_exception(MICROPY_ERROR_PRINTER, MP_OBJ_FROM_PTR(exc));

}

}

DEBUG_printf("[thread] finish ts=%p\n", &ts);

// signal that we are finished

mp_thread_finish();

MP_THREAD_GIL_EXIT();

return NULL;

}

STATIC mp_obj_t mod_thread_start_new_thread(size_t n_args, const mp_obj_t *args) {

// This structure holds the Python function and arguments for thread entry.

// We copy all arguments into this structure to keep ownership of them.

// We must be very careful about root pointers because this pointer may

// disappear from our address space before the thread is created.

thread_entry_args_t *th_args;

// get positional arguments

size_t pos_args_len;

mp_obj_t *pos_args_items;

mp_obj_get_array(args[1], &pos_args_len, &pos_args_items);

// check for keyword arguments

if (n_args == 2) {

// just position arguments

th_args = m_new_obj_var(thread_entry_args_t, mp_obj_t, pos_args_len);

th_args->n_kw = 0;

} else {

// positional and keyword arguments

if (mp_obj_get_type(args[2]) != &mp_type_dict) {

mp_raise_TypeError(MP_ERROR_TEXT("expecting a dict for keyword args"));

}

mp_map_t *map = &((mp_obj_dict_t *)MP_OBJ_TO_PTR(args[2]))->map;

th_args = m_new_obj_var(thread_entry_args_t, mp_obj_t, pos_args_len + 2 * map->used);

th_args->n_kw = map->used;

// copy across the keyword arguments

for (size_t i = 0, n = pos_args_len; i < map->alloc; ++i) {

if (mp_map_slot_is_filled(map, i)) {

th_args->args[n++] = map->table[i].key;

th_args->args[n++] = map->table[i].value;

}

}

}

// copy across the positional arguments

th_args->n_args = pos_args_len;

memcpy(th_args->args, pos_args_items, pos_args_len * sizeof(mp_obj_t));

// pass our locals and globals into the new thread

th_args->dict_locals = mp_locals_get();

th_args->dict_globals = mp_globals_get();

// set the stack size to use

th_args->stack_size = thread_stack_size;

// set the function for thread entry

th_args->fun = args[0];

// spawn the thread!

mp_thread_create(thread_entry, th_args, &th_args->stack_size);

return mp_const_none;

}

STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_thread_start_new_thread_obj, 2, 3, mod_thread_start_new_thread);

STATIC mp_obj_t mod_thread_exit(void) {

mp_raise_type(&mp_type_SystemExit);

}

STATIC MP_DEFINE_CONST_FUN_OBJ_0(mod_thread_exit_obj, mod_thread_exit);

STATIC mp_obj_t mod_thread_allocate_lock(void) {

return MP_OBJ_FROM_PTR(mp_obj_new_thread_lock());

}

STATIC MP_DEFINE_CONST_FUN_OBJ_0(mod_thread_allocate_lock_obj, mod_thread_allocate_lock);

STATIC const mp_rom_map_elem_t mp_module_thread_globals_table[] = {

{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR__thread) },

{ MP_ROM_QSTR(MP_QSTR_LockType), MP_ROM_PTR(&mp_type_thread_lock) },

{ MP_ROM_QSTR(MP_QSTR_get_ident), MP_ROM_PTR(&mod_thread_get_ident_obj) },

{ MP_ROM_QSTR(MP_QSTR_stack_size), MP_ROM_PTR(&mod_thread_stack_size_obj) },

{ MP_ROM_QSTR(MP_QSTR_start_new_thread), MP_ROM_PTR(&mod_thread_start_new_thread_obj) },

{ MP_ROM_QSTR(MP_QSTR_exit), MP_ROM_PTR(&mod_thread_exit_obj) },

{ MP_ROM_QSTR(MP_QSTR_allocate_lock), MP_ROM_PTR(&mod_thread_allocate_lock_obj) },

};

STATIC MP_DEFINE_CONST_DICT(mp_module_thread_globals, mp_module_thread_globals_table);

const mp_obj_module_t mp_module_thread = {

.base = { &mp_type_module },

.globals = (mp_obj_dict_t *)&mp_module_thread_globals,

};

#endif // MICROPY_PY_THREAD