circuitpython/ports/espressif/bindings/espnow/ESPNow.c

/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2017-2020 Nick Moore
 * Copyright (c) 2018 shawwwn <shawwwn1@gmail.com>
 * Copyright (c) 2020-2021 Glenn Moloney @glenn20
 * Copyright (c) 2023 MicroDev
 *
 * 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 "py/runtime.h"
#include "py/objarray.h"
#include "py/objproperty.h"
#include "py/stream.h"

#include "bindings/espnow/ESPNow.h"

#include "shared-bindings/util.h"

#include "common-hal/espnow/ESPNow.h"

#include "esp_now.h"

// Return C pointer to byte memory string/bytes/bytearray in obj.
// Raise ValueError if the length does not match expected len.
static const uint8_t *_get_bytes_len(mp_obj_t obj, size_t len, mp_uint_t rw) {
    mp_buffer_info_t bufinfo;
    mp_get_buffer_raise(obj, &bufinfo, rw);
    mp_arg_validate_length(bufinfo.len, len, MP_QSTR_buffer);
    return (uint8_t *)bufinfo.buf;
}

// Return C pointer to the MAC address.
// Raise ValueError if mac is wrong type or is not 6 bytes long.
static const uint8_t *_get_peer_addr(mp_obj_t mac) {
    return mp_obj_is_true(mac) ? _get_bytes_len(mac, ESP_NOW_ETH_ALEN, MP_BUFFER_READ) : NULL;
}

// --- Initialisation and Config functions ---

static void check_for_deinit(espnow_obj_t *self) {
    if (common_hal_espnow_deinited(self)) {
        raise_deinited_error();
    }
}

//| class ESPNow:
//|     """Provides access to the ESP-NOW protocol."""
//|
//|     def __init__(self, buffer_size: Optional[int], phy_rate: Optional[int]) -> None:
//|         """Allocate and initialize `ESPNow` instance as a singleton.
//|
//|         :param int buffer_size: The size of the internal ring buffer. Default: 526 bytes.
//|         :param int phy_rate: The ESP-NOW physical layer rate. Default: 1 Mbps."""
//|         ...
STATIC mp_obj_t espnow_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
    enum { ARG_buffer_size, ARG_phy_rate };
    static const mp_arg_t allowed_args[] = {
        { MP_QSTR_buffer_size,  MP_ARG_INT, { .u_int = 526 } },
        { MP_QSTR_phy_rate,     MP_ARG_INT, { .u_int = WIFI_PHY_RATE_1M_L } },
    };

    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
    mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);

    espnow_obj_t *self = MP_STATE_PORT(espnow_singleton);

    if (self != NULL) {
        mp_raise_RuntimeError(translate("Already running"));
    }

    self = m_new_obj(espnow_obj_t);
    self->base.type = &espnow_type;

    common_hal_espnow_set_buffer_size(self, args[ARG_buffer_size].u_int);
    common_hal_espnow_set_phy_rate(self, args[ARG_phy_rate].u_int);

    self->peers = espnow_peers_new();

    // Set the global singleton pointer for the espnow protocol.
    MP_STATE_PORT(espnow_singleton) = self;

    common_hal_espnow_init(self);

    return self;
}

//|     def deinit(self) -> None:
//|         """Deinitializes ESP-NOW and releases it for another program."""
//|         ...
STATIC mp_obj_t espnow_deinit(mp_obj_t self_in) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    common_hal_espnow_deinit(self);
    return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(espnow_deinit_obj, espnow_deinit);

//|     def __enter__(self) -> ESPNow:
//|         """No-op used by Context Managers."""
//|         ...
//  Provided by context manager helper.

//|     def __exit__(self) -> None:
//|         """Automatically deinitializes the hardware when exiting a context. See
//|         :ref:`lifetime-and-contextmanagers` for more info."""
//|         ...
STATIC mp_obj_t espnow_obj___exit__(size_t n_args, const mp_obj_t *args) {
    (void)n_args;
    return espnow_deinit(args[0]);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(espnow___exit___obj, 4, 4, espnow_obj___exit__);

//|     def set_pmk(self, pmk: ReadableBuffer) -> None:
//|         """Set the ESP-NOW Primary Master Key (pmk) for encrypted communications.
//|
//|         :param ReadableBuffer pmk: The ESP-NOW Primary Master Key (length = 16 bytes)."""
//|         ...
STATIC mp_obj_t espnow_set_pmk(mp_obj_t self_in, mp_obj_t key) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    common_hal_espnow_set_pmk(self, _get_bytes_len(key, ESP_NOW_KEY_LEN, MP_BUFFER_READ));
    return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(espnow_set_pmk_obj, espnow_set_pmk);

//|     buffer_size: int
//|     """The size of the internal ring buffer."""
//|
STATIC mp_obj_t espnow_get_buffer_size(const mp_obj_t self_in) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    return MP_OBJ_NEW_SMALL_INT(self->recv_buffer_size);
}
MP_DEFINE_CONST_FUN_OBJ_1(espnow_get_buffer_size_obj, espnow_get_buffer_size);

STATIC mp_obj_t espnow_set_buffer_size(const mp_obj_t self_in, const mp_obj_t value) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    common_hal_espnow_set_buffer_size(self, mp_obj_get_int(value));
    return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(espnow_set_buffer_size_obj, espnow_set_buffer_size);

MP_PROPERTY_GETSET(espnow_buffer_size_obj,
    (mp_obj_t)&espnow_get_buffer_size_obj,
    (mp_obj_t)&espnow_set_buffer_size_obj);

//|     phy_rate: int
//|     """The ESP-NOW physical layer rate."""
//|
STATIC mp_obj_t espnow_get_phy_rate(const mp_obj_t self_in) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    return MP_OBJ_NEW_SMALL_INT(self->phy_rate);
}
MP_DEFINE_CONST_FUN_OBJ_1(espnow_get_phy_rate_obj, espnow_get_phy_rate);

STATIC mp_obj_t espnow_set_phy_rate(const mp_obj_t self_in, const mp_obj_t value) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    common_hal_espnow_set_phy_rate(self, mp_obj_get_int(value));
    return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(espnow_set_phy_rate_obj, espnow_set_phy_rate);

MP_PROPERTY_GETSET(espnow_phy_rate_obj,
    (mp_obj_t)&espnow_get_phy_rate_obj,
    (mp_obj_t)&espnow_set_phy_rate_obj);

//|     stats: Tuple[int, int, int, int, int]
//|     """Provide some useful stats in a `tuple` of
//|        (tx_packets, tx_responses, tx_failures, rx_packets, rx_failures). (read-only)"""
//|
STATIC mp_obj_t espnow_get_stats(mp_obj_t self_in) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    return MP_OBJ_NEW_TUPLE(
        mp_obj_new_int(self->tx_packets),
        mp_obj_new_int(self->tx_responses),
        mp_obj_new_int(self->tx_failures),
        mp_obj_new_int(self->rx_packets),
        mp_obj_new_int(self->rx_failures));
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(espnow_get_stats_obj, espnow_get_stats);

MP_PROPERTY_GETTER(espnow_stats_obj,
    (mp_obj_t)&espnow_get_stats_obj);

// --- Send and Receive ESP-NOW data ---

//|     def send(
//|         self,
//|         message: ReadableBuffer,
//|         mac: Optional[ReadableBuffer],
//|     ) -> bool:
//|         """Send a message to the peer's mac address.
//|
//|         :param ReadableBuffer message: The message to send (length <= 250 bytes).
//|         :param ReadableBuffer mac: The peer's address (length = 6 bytes). If `None` or any non-true value, send to all registered peers.
//|
//|         :raises EAGAIN: if the internal espnow buffers are full."""
//|         ...
STATIC mp_obj_t espnow_send(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
    enum { ARG_message, ARG_mac, ARG_sync };
    static const mp_arg_t allowed_args[] = {
        { MP_QSTR_message,  MP_ARG_OBJ | MP_ARG_REQUIRED },
        { MP_QSTR_mac,      MP_ARG_OBJ, { .u_obj = mp_const_none } },
    };

    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
    mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);

    espnow_obj_t *self = pos_args[0];
    check_for_deinit(self);

    const uint8_t *peer_addr = _get_peer_addr(args[ARG_mac].u_obj);

    // Get a pointer to the data buffer of the message
    mp_buffer_info_t message;
    mp_get_buffer_raise(args[ARG_message].u_obj, &message, MP_BUFFER_READ);

    return common_hal_espnow_send(self, peer_addr, &message);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(espnow_send_obj, 2, espnow_send);

//|     def recv(self) -> Optional[ESPNowPacket]:
//|         """Receive a message from the peer(s).
//|
//|         :returns: An `ESPNowPacket` if available in the buffer, otherwise `None`."""
//|         ...
STATIC mp_obj_t espnow_recv(mp_obj_t self_in) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    check_for_deinit(self);

    return common_hal_espnow_recv(self);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(espnow_recv_obj, espnow_recv);

// --- Peer Related Properties ---

//|     peers: Peers
//|     """The peer info records for all registered `ESPNow` peers. (read-only)"""
//|
STATIC mp_obj_t espnow_get_peers(mp_obj_t self_in) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    check_for_deinit(self);
    return MP_OBJ_FROM_PTR(self->peers);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(espnow_get_peers_obj, espnow_get_peers);

MP_PROPERTY_GETTER(espnow_peers_obj,
    (mp_obj_t)&espnow_get_peers_obj);

STATIC const mp_rom_map_elem_t espnow_locals_dict_table[] = {
    // Context managers
    { MP_ROM_QSTR(MP_QSTR___enter__),   MP_ROM_PTR(&mp_identity_obj) },
    { MP_ROM_QSTR(MP_QSTR___exit__),    MP_ROM_PTR(&espnow___exit___obj) },

    { MP_ROM_QSTR(MP_QSTR_deinit),      MP_ROM_PTR(&espnow_deinit_obj) },

    // Config parameters
    { MP_ROM_QSTR(MP_QSTR_set_pmk),     MP_ROM_PTR(&espnow_set_pmk_obj) },
    { MP_ROM_QSTR(MP_QSTR_buffer_size), MP_ROM_PTR(&espnow_buffer_size_obj) },
    { MP_ROM_QSTR(MP_QSTR_phy_rate),    MP_ROM_PTR(&espnow_phy_rate_obj) },

    { MP_ROM_QSTR(MP_QSTR_stats),       MP_ROM_PTR(&espnow_stats_obj) },

    // Send and receive messages
    { MP_ROM_QSTR(MP_QSTR_send),        MP_ROM_PTR(&espnow_send_obj) },
    { MP_ROM_QSTR(MP_QSTR_recv),        MP_ROM_PTR(&espnow_recv_obj) },

    // Peer related properties
    { MP_ROM_QSTR(MP_QSTR_peers),       MP_ROM_PTR(&espnow_peers_obj) },
};
STATIC MP_DEFINE_CONST_DICT(espnow_locals_dict, espnow_locals_dict_table);

// --- Dummy Buffer Protocol support ---
// ...so asyncio can poll.ipoll() on this device

// Support ioctl(MP_STREAM_POLL, ) for asyncio
STATIC mp_uint_t espnow_stream_ioctl(mp_obj_t self_in, mp_uint_t request, uintptr_t arg, int *errcode) {
    if (request != MP_STREAM_POLL) {
        *errcode = MP_EINVAL;
        return MP_STREAM_ERROR;
    }

    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    return (common_hal_espnow_deinited(self)) ? 0 : // If not initialized
           arg ^ (
               // If no data in the buffer, unset the Read ready flag
               ((!ringbuf_num_filled(self->recv_buffer)) ? MP_STREAM_POLL_RD : 0) |
               // If still waiting for responses, unset the Write ready flag
               ((self->tx_responses < self->tx_packets) ? MP_STREAM_POLL_WR : 0));
}

STATIC const mp_stream_p_t espnow_stream_p = {
    .ioctl = espnow_stream_ioctl,
};

//|     def __bool__(self) -> bool:
//|         """``True`` if `len()` is greater than zero.
//|         This is an easy way to check if the buffer is empty.
//|         """
//|         ...
//|     def __len__(self) -> int:
//|         """Return the number of `bytes` available to read. Used to implement ``len()``."""
//|         ...
//|
STATIC mp_obj_t espnow_unary_op(mp_unary_op_t op, mp_obj_t self_in) {
    espnow_obj_t *self = MP_OBJ_TO_PTR(self_in);
    size_t len = ringbuf_num_filled(self->recv_buffer);
    switch (op) {
        case MP_UNARY_OP_BOOL:
            return mp_obj_new_bool(len != 0);
        case MP_UNARY_OP_LEN:
            return mp_obj_new_int_from_uint(len);
        default:
            return MP_OBJ_NULL; // op not supported
    }
}

const mp_obj_type_t espnow_type = {
    { &mp_type_type },
    .name = MP_QSTR_ESPNow,
    .make_new = espnow_make_new,
    .locals_dict = (mp_obj_t)&espnow_locals_dict,
    .flags = MP_TYPE_FLAG_EXTENDED,
    MP_TYPE_EXTENDED_FIELDS(
        .protocol = &espnow_stream_p,
        .unary_op = &espnow_unary_op
        ),
};