diff options
Diffstat (limited to 'thirdparty/nRF5_SDK_15.0.0_a53641a/external/lwip/src/apps/mqtt/mqtt.c')
| -rw-r--r-- | thirdparty/nRF5_SDK_15.0.0_a53641a/external/lwip/src/apps/mqtt/mqtt.c | 1341 |
1 files changed, 1341 insertions, 0 deletions
diff --git a/thirdparty/nRF5_SDK_15.0.0_a53641a/external/lwip/src/apps/mqtt/mqtt.c b/thirdparty/nRF5_SDK_15.0.0_a53641a/external/lwip/src/apps/mqtt/mqtt.c new file mode 100644 index 0000000..a0e77b9 --- /dev/null +++ b/thirdparty/nRF5_SDK_15.0.0_a53641a/external/lwip/src/apps/mqtt/mqtt.c @@ -0,0 +1,1341 @@ +/** + * @file + * MQTT client + * + * @defgroup mqtt MQTT client + * @ingroup apps + * @verbinclude mqtt_client.txt + */ + +/* + * Copyright (c) 2016 Erik Andersson <erian747@gmail.com> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, + * are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT + * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT + * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING + * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY + * OF SUCH DAMAGE. + * + * This file is part of the lwIP TCP/IP stack + * + * Author: Erik Andersson <erian747@gmail.com> + * + * + * @todo: + * - Handle large outgoing payloads for PUBLISH messages + * - Fix restriction of a single topic in each (UN)SUBSCRIBE message (protocol has support for multiple topics) + * - Add support for legacy MQTT protocol version + * + * Please coordinate changes and requests with Erik Andersson + * Erik Andersson <erian747@gmail.com> + * + */ +#include "lwip/apps/mqtt.h" +#include "lwip/timeouts.h" +#include "lwip/ip_addr.h" +#include "lwip/mem.h" +#include "lwip/err.h" +#include "lwip/pbuf.h" +#include "lwip/tcp.h" +#include <string.h> + +#if LWIP_TCP && LWIP_CALLBACK_API + +/** + * MQTT_DEBUG: Default is off. + */ +#if !defined MQTT_DEBUG || defined __DOXYGEN__ +#define MQTT_DEBUG LWIP_DBG_OFF +#endif + +#define MQTT_DEBUG_TRACE (MQTT_DEBUG | LWIP_DBG_TRACE) +#define MQTT_DEBUG_STATE (MQTT_DEBUG | LWIP_DBG_STATE) +#define MQTT_DEBUG_WARN (MQTT_DEBUG | LWIP_DBG_LEVEL_WARNING) +#define MQTT_DEBUG_WARN_STATE (MQTT_DEBUG | LWIP_DBG_LEVEL_WARNING | LWIP_DBG_STATE) +#define MQTT_DEBUG_SERIOUS (MQTT_DEBUG | LWIP_DBG_LEVEL_SERIOUS) + +static void mqtt_cyclic_timer(void *arg); + +/** + * MQTT client connection states + */ +enum { + TCP_DISCONNECTED, + TCP_CONNECTING, + MQTT_CONNECTING, + MQTT_CONNECTED +}; + +/** + * MQTT control message types + */ +enum mqtt_message_type { + MQTT_MSG_TYPE_CONNECT = 1, + MQTT_MSG_TYPE_CONNACK = 2, + MQTT_MSG_TYPE_PUBLISH = 3, + MQTT_MSG_TYPE_PUBACK = 4, + MQTT_MSG_TYPE_PUBREC = 5, + MQTT_MSG_TYPE_PUBREL = 6, + MQTT_MSG_TYPE_PUBCOMP = 7, + MQTT_MSG_TYPE_SUBSCRIBE = 8, + MQTT_MSG_TYPE_SUBACK = 9, + MQTT_MSG_TYPE_UNSUBSCRIBE = 10, + MQTT_MSG_TYPE_UNSUBACK = 11, + MQTT_MSG_TYPE_PINGREQ = 12, + MQTT_MSG_TYPE_PINGRESP = 13, + MQTT_MSG_TYPE_DISCONNECT = 14 +}; + +/** Helpers to extract control packet type and qos from first byte in fixed header */ +#define MQTT_CTL_PACKET_TYPE(fixed_hdr_byte0) ((fixed_hdr_byte0 & 0xf0) >> 4) +#define MQTT_CTL_PACKET_QOS(fixed_hdr_byte0) ((fixed_hdr_byte0 & 0x6) >> 1) + +/** + * MQTT connect flags, only used in CONNECT message + */ +enum mqtt_connect_flag { + MQTT_CONNECT_FLAG_USERNAME = 1 << 7, + MQTT_CONNECT_FLAG_PASSWORD = 1 << 6, + MQTT_CONNECT_FLAG_WILL_RETAIN = 1 << 5, + MQTT_CONNECT_FLAG_WILL = 1 << 2, + MQTT_CONNECT_FLAG_CLEAN_SESSION = 1 << 1 +}; + + +#if defined(LWIP_DEBUG) +static const char * const mqtt_message_type_str[15] = +{ + "UNDEFINED", + "CONNECT", + "CONNACK", + "PUBLISH", + "PUBACK", + "PUBREC", + "PUBREL", + "PUBCOMP", + "SUBSCRIBE", + "SUBACK", + "UNSUBSCRIBE", + "UNSUBACK", + "PINGREQ", + "PINGRESP", + "DISCONNECT" +}; + +/** + * Message type value to string + * @param msg_type see enum mqtt_message_type + * + * @return Control message type text string + */ +static const char * +mqtt_msg_type_to_str(u8_t msg_type) +{ + if (msg_type >= LWIP_ARRAYSIZE(mqtt_message_type_str)) { + msg_type = 0; + } + return mqtt_message_type_str[msg_type]; +} + +#endif + + +/** + * Generate MQTT packet identifier + * @param client MQTT client + * @return New packet identifier, range 1 to 65535 + */ +static u16_t +msg_generate_packet_id(mqtt_client_t *client) +{ + client->pkt_id_seq++; + if (client->pkt_id_seq == 0) { + client->pkt_id_seq++; + } + return client->pkt_id_seq; +} + +/*--------------------------------------------------------------------------------------------------------------------- */ +/* Output ring buffer */ + + +#define MQTT_RINGBUF_IDX_MASK ((MQTT_OUTPUT_RINGBUF_SIZE) - 1) + +/** Add single item to ring buffer */ +#define mqtt_ringbuf_put(rb, item) ((rb)->buf)[(rb)->put++ & MQTT_RINGBUF_IDX_MASK] = (item) + +/** Return number of bytes in ring buffer */ +#define mqtt_ringbuf_len(rb) ((u16_t)((rb)->put - (rb)->get)) + +/** Return number of bytes free in ring buffer */ +#define mqtt_ringbuf_free(rb) (MQTT_OUTPUT_RINGBUF_SIZE - mqtt_ringbuf_len(rb)) + +/** Return number of bytes possible to read without wrapping around */ +#define mqtt_ringbuf_linear_read_length(rb) LWIP_MIN(mqtt_ringbuf_len(rb), (MQTT_OUTPUT_RINGBUF_SIZE - ((rb)->get & MQTT_RINGBUF_IDX_MASK))) + +/** Return pointer to ring buffer get position */ +#define mqtt_ringbuf_get_ptr(rb) (&(rb)->buf[(rb)->get & MQTT_RINGBUF_IDX_MASK]) + +#define mqtt_ringbuf_advance_get_idx(rb, len) ((rb)->get += (len)) + + +/** + * Try send as many bytes as possible from output ring buffer + * @param rb Output ring buffer + * @param tpcb TCP connection handle + */ +static void +mqtt_output_send(struct mqtt_ringbuf_t *rb, struct tcp_pcb *tpcb) +{ + err_t err; + u8_t wrap = 0; + u16_t ringbuf_lin_len = mqtt_ringbuf_linear_read_length(rb); + u16_t send_len = tcp_sndbuf(tpcb); + LWIP_ASSERT("mqtt_output_send: tpcb != NULL", tpcb != NULL); + + if (send_len == 0 || ringbuf_lin_len == 0) { + return; + } + + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_output_send: tcp_sndbuf: %d bytes, ringbuf_linear_available: %d, get %d, put %d\n", + send_len, ringbuf_lin_len, ((rb)->get & MQTT_RINGBUF_IDX_MASK), ((rb)->put & MQTT_RINGBUF_IDX_MASK))); + + if (send_len > ringbuf_lin_len) { + /* Space in TCP output buffer is larger than available in ring buffer linear portion */ + send_len = ringbuf_lin_len; + /* Wrap around if more data in ring buffer after linear portion */ + wrap = (mqtt_ringbuf_len(rb) > ringbuf_lin_len); + } + err = tcp_write(tpcb, mqtt_ringbuf_get_ptr(rb), send_len, TCP_WRITE_FLAG_COPY | (wrap ? TCP_WRITE_FLAG_MORE : 0)); + if ((err == ERR_OK) && wrap) { + mqtt_ringbuf_advance_get_idx(rb, send_len); + /* Use the lesser one of ring buffer linear length and TCP send buffer size */ + send_len = LWIP_MIN(tcp_sndbuf(tpcb), mqtt_ringbuf_linear_read_length(rb)); + err = tcp_write(tpcb, mqtt_ringbuf_get_ptr(rb), send_len, TCP_WRITE_FLAG_COPY); + } + + if (err == ERR_OK) { + mqtt_ringbuf_advance_get_idx(rb, send_len); + /* Flush */ + tcp_output(tpcb); + } else { + LWIP_DEBUGF(MQTT_DEBUG_WARN, ("mqtt_output_send: Send failed with err %d (\"%s\")\n", err, lwip_strerr(err))); + } +} + + + +/*--------------------------------------------------------------------------------------------------------------------- */ +/* Request queue */ + +/** + * Create request item + * @param r_objs Pointer to request objects + * @param pkt_id Packet identifier of request + * @param cb Packet callback to call when requests lifetime ends + * @param arg Parameter following callback + * @return Request or NULL if failed to create + */ +static struct mqtt_request_t * +mqtt_create_request(struct mqtt_request_t *r_objs, u16_t pkt_id, mqtt_request_cb_t cb, void *arg) +{ + struct mqtt_request_t *r = NULL; + u8_t n; + LWIP_ASSERT("mqtt_create_request: r_objs != NULL", r_objs != NULL); + for (n = 0; n < MQTT_REQ_MAX_IN_FLIGHT; n++) { + /* Item point to itself if not in use */ + if (r_objs[n].next == &r_objs[n]) { + r = &r_objs[n]; + r->next = NULL; + r->cb = cb; + r->arg = arg; + r->pkt_id = pkt_id; + break; + } + } + return r; +} + + +/** + * Append request to pending request queue + * @param tail Pointer to request queue tail pointer + * @param r Request to append + */ +static void +mqtt_append_request(struct mqtt_request_t **tail, struct mqtt_request_t *r) +{ + struct mqtt_request_t *head = NULL; + s16_t time_before = 0; + struct mqtt_request_t *iter; + + LWIP_ASSERT("mqtt_append_request: tail != NULL", tail != NULL); + + /* Iterate trough queue to find head, and count total timeout time */ + for (iter = *tail; iter != NULL; iter = iter->next) { + time_before += iter->timeout_diff; + head = iter; + } + + LWIP_ASSERT("mqtt_append_request: time_before <= MQTT_REQ_TIMEOUT", time_before <= MQTT_REQ_TIMEOUT); + r->timeout_diff = MQTT_REQ_TIMEOUT - time_before; + if (head == NULL) { + *tail = r; + } else { + head->next = r; + } +} + + +/** + * Delete request item + * @param r Request item to delete + */ +static void +mqtt_delete_request(struct mqtt_request_t *r) +{ + if (r != NULL) { + r->next = r; + } +} + +/** + * Remove a request item with a specific packet identifier from request queue + * @param tail Pointer to request queue tail pointer + * @param pkt_id Packet identifier of request to take + * @return Request item if found, NULL if not + */ +static struct mqtt_request_t * +mqtt_take_request(struct mqtt_request_t **tail, u16_t pkt_id) +{ + struct mqtt_request_t *iter = NULL, *prev = NULL; + LWIP_ASSERT("mqtt_take_request: tail != NULL", tail != NULL); + /* Search all request for pkt_id */ + for (iter = *tail; iter != NULL; iter = iter->next) { + if (iter->pkt_id == pkt_id) { + break; + } + prev = iter; + } + + /* If request was found */ + if (iter != NULL) { + /* unchain */ + if (prev == NULL) { + *tail= iter->next; + } else { + prev->next = iter->next; + } + /* If exists, add remaining timeout time for the request to next */ + if (iter->next != NULL) { + iter->next->timeout_diff += iter->timeout_diff; + } + iter->next = NULL; + } + return iter; +} + +/** + * Handle requests timeout + * @param tail Pointer to request queue tail pointer + * @param t Time since last call in seconds + */ +static void +mqtt_request_time_elapsed(struct mqtt_request_t **tail, u8_t t) +{ + struct mqtt_request_t *r = *tail; + LWIP_ASSERT("mqtt_request_time_elapsed: tail != NULL", tail != NULL); + while (t > 0 && r != NULL) { + if (t >= r->timeout_diff) { + t -= (u8_t)r->timeout_diff; + /* Unchain */ + *tail = r->next; + /* Notify upper layer about timeout */ + if (r->cb != NULL) { + r->cb(r->arg, ERR_TIMEOUT); + } + mqtt_delete_request(r); + /* Tail might be be modified in callback, so re-read it in every iteration */ + r = *(struct mqtt_request_t * const volatile *)tail; + } else { + r->timeout_diff -= t; + t = 0; + } + } +} + +/** + * Free all request items + * @param tail Pointer to request queue tail pointer + */ +static void +mqtt_clear_requests(struct mqtt_request_t **tail) +{ + struct mqtt_request_t *iter, *next; + LWIP_ASSERT("mqtt_clear_requests: tail != NULL", tail != NULL); + for (iter = *tail; iter != NULL; iter = next) { + next = iter->next; + mqtt_delete_request(iter); + } + *tail = NULL; +} +/** + * Initialize all request items + * @param r_objs Pointer to request objects + */ +static void +mqtt_init_requests(struct mqtt_request_t *r_objs) +{ + u8_t n; + LWIP_ASSERT("mqtt_init_requests: r_objs != NULL", r_objs != NULL); + for (n = 0; n < MQTT_REQ_MAX_IN_FLIGHT; n++) { + /* Item pointing to itself indicates unused */ + r_objs[n].next = &r_objs[n]; + } +} + +/*--------------------------------------------------------------------------------------------------------------------- */ +/* Output message build helpers */ + + +static void +mqtt_output_append_u8(struct mqtt_ringbuf_t *rb, u8_t value) +{ + mqtt_ringbuf_put(rb, value); +} + +static +void mqtt_output_append_u16(struct mqtt_ringbuf_t *rb, u16_t value) +{ + mqtt_ringbuf_put(rb, value >> 8); + mqtt_ringbuf_put(rb, value & 0xff); +} + +static void +mqtt_output_append_buf(struct mqtt_ringbuf_t *rb, const void *data, u16_t length) +{ + u16_t n; + for (n = 0; n < length; n++) { + mqtt_ringbuf_put(rb, ((const u8_t *)data)[n]); + } +} + +static void +mqtt_output_append_string(struct mqtt_ringbuf_t *rb, const char *str, u16_t length) +{ + u16_t n; + mqtt_ringbuf_put(rb, length >> 8); + mqtt_ringbuf_put(rb, length & 0xff); + for (n = 0; n < length; n++) { + mqtt_ringbuf_put(rb, str[n]); + } +} + +/** + * Append fixed header + * @param rb Output ring buffer + * @param msg_type see enum mqtt_message_type + * @param dup MQTT DUP flag + * @param qos MQTT QoS field + * @param retain MQTT retain flag + * @param r_length Remaining length after fixed header + */ + +static void +mqtt_output_append_fixed_header(struct mqtt_ringbuf_t *rb, u8_t msg_type, u8_t dup, + u8_t qos, u8_t retain, u16_t r_length) +{ + /* Start with control byte */ + mqtt_output_append_u8(rb, (((msg_type & 0x0f) << 4) | ((dup & 1) << 3) | ((qos & 3) << 1) | (retain & 1))); + /* Encode remaining length field */ + do { + mqtt_output_append_u8(rb, (r_length & 0x7f) | (r_length >= 128 ? 0x80 : 0)); + r_length >>= 7; + } while (r_length > 0); +} + + +/** + * Check output buffer space + * @param rb Output ring buffer + * @param r_length Remaining length after fixed header + * @return 1 if message will fit, 0 if not enough buffer space + */ +static u8_t +mqtt_output_check_space(struct mqtt_ringbuf_t *rb, u16_t r_length) +{ + /* Start with length of type byte + remaining length */ + u16_t total_len = 1 + r_length; + + LWIP_ASSERT("mqtt_output_check_space: rb != NULL", rb != NULL); + + /* Calculate number of required bytes to contain the remaining bytes field and add to total*/ + do { + total_len++; + r_length >>= 7; + } while (r_length > 0); + + return (total_len <= mqtt_ringbuf_free(rb)); +} + + +/** + * Close connection to server + * @param client MQTT client + * @param reason Reason for disconnection + */ +static void +mqtt_close(mqtt_client_t *client, mqtt_connection_status_t reason) +{ + LWIP_ASSERT("mqtt_close: client != NULL", client != NULL); + + /* Bring down TCP connection if not already done */ + if (client->conn != NULL) { + err_t res; + tcp_recv(client->conn, NULL); + tcp_err(client->conn, NULL); + tcp_sent(client->conn, NULL); + res = tcp_close(client->conn); + if (res != ERR_OK) { + tcp_abort(client->conn); + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_close: Close err=%s\n", lwip_strerr(res))); + } + client->conn = NULL; + } + + /* Remove all pending requests */ + mqtt_clear_requests(&client->pend_req_queue); + /* Stop cyclic timer */ + sys_untimeout(mqtt_cyclic_timer, client); + + /* Notify upper layer of disconnection if changed state */ + if (client->conn_state != TCP_DISCONNECTED) { + + client->conn_state = TCP_DISCONNECTED; + if (client->connect_cb != NULL) { + client->connect_cb(client, client->connect_arg, reason); + } + } +} + + +/** + * Interval timer, called every MQTT_CYCLIC_TIMER_INTERVAL seconds in MQTT_CONNECTING and MQTT_CONNECTED states + * @param arg MQTT client + */ +static void +mqtt_cyclic_timer(void *arg) +{ + u8_t restart_timer = 1; + mqtt_client_t *client = (mqtt_client_t *)arg; + LWIP_ASSERT("mqtt_cyclic_timer: client != NULL", client != NULL); + + if (client->conn_state == MQTT_CONNECTING) { + client->cyclic_tick++; + if ((client->cyclic_tick * MQTT_CYCLIC_TIMER_INTERVAL) >= MQTT_CONNECT_TIMOUT) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_cyclic_timer: CONNECT attempt to server timed out\n")); + /* Disconnect TCP */ + mqtt_close(client, MQTT_CONNECT_TIMEOUT); + restart_timer = 0; + } + } else if (client->conn_state == MQTT_CONNECTED) { + /* Handle timeout for pending requests */ + mqtt_request_time_elapsed(&client->pend_req_queue, MQTT_CYCLIC_TIMER_INTERVAL); + + /* keep_alive > 0 means keep alive functionality shall be used */ + if (client->keep_alive > 0) { + + client->server_watchdog++; + /* If reception from server has been idle for 1.5*keep_alive time, server is considered unresponsive */ + if ((client->server_watchdog * MQTT_CYCLIC_TIMER_INTERVAL) > (client->keep_alive + client->keep_alive/2)) { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_cyclic_timer: Server incoming keep-alive timeout\n")); + mqtt_close(client, MQTT_CONNECT_TIMEOUT); + restart_timer = 0; + } + + /* If time for a keep alive message to be sent, transmission has been idle for keep_alive time */ + if ((client->cyclic_tick * MQTT_CYCLIC_TIMER_INTERVAL) >= client->keep_alive) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_cyclic_timer: Sending keep-alive message to server\n")); + if (mqtt_output_check_space(&client->output, 0) != 0) { + mqtt_output_append_fixed_header(&client->output, MQTT_MSG_TYPE_PINGREQ, 0, 0, 0, 0); + client->cyclic_tick = 0; + } + } else { + client->cyclic_tick++; + } + } + } else { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_cyclic_timer: Timer should not be running in state %d\n", client->conn_state)); + restart_timer = 0; + } + if (restart_timer) { + sys_timeout(MQTT_CYCLIC_TIMER_INTERVAL*1000, mqtt_cyclic_timer, arg); + } +} + + +/** + * Send PUBACK, PUBREC or PUBREL response message + * @param client MQTT client + * @param msg PUBACK, PUBREC or PUBREL + * @param pkt_id Packet identifier + * @param qos QoS value + * @return ERR_OK if successful, ERR_MEM if out of memory + */ +static err_t +pub_ack_rec_rel_response(mqtt_client_t *client, u8_t msg, u16_t pkt_id, u8_t qos) +{ + err_t err = ERR_OK; + if (mqtt_output_check_space(&client->output, 2)) { + mqtt_output_append_fixed_header(&client->output, msg, 0, qos, 0, 2); + mqtt_output_append_u16(&client->output, pkt_id); + mqtt_output_send(&client->output, client->conn); + } else { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("pub_ack_rec_rel_response: OOM creating response: %s with pkt_id: %d\n", + mqtt_msg_type_to_str(msg), pkt_id)); + err = ERR_MEM; + } + return err; +} + +/** + * Subscribe response from server + * @param r Matching request + * @param result Result code from server + */ +static void +mqtt_incomming_suback(struct mqtt_request_t *r, u8_t result) +{ + if (r->cb != NULL) { + r->cb(r->arg, result < 3 ? ERR_OK : ERR_ABRT); + } +} + + +/** + * Complete MQTT message received or buffer full + * @param client MQTT client + * @param fixed_hdr_idx header index + * @param length length received part + * @param remaining_length Remaining length of complete message + */ +static mqtt_connection_status_t + mqtt_message_received(mqtt_client_t *client, u8_t fixed_hdr_idx, u16_t length, u32_t remaining_length) +{ + mqtt_connection_status_t res = MQTT_CONNECT_ACCEPTED; + + u8_t *var_hdr_payload = client->rx_buffer + fixed_hdr_idx; + + /* Control packet type */ + u8_t pkt_type = MQTT_CTL_PACKET_TYPE(client->rx_buffer[0]); + u16_t pkt_id = 0; + + if (pkt_type == MQTT_MSG_TYPE_CONNACK) { + if (client->conn_state == MQTT_CONNECTING) { + /* Get result code from CONNACK */ + res = (mqtt_connection_status_t)var_hdr_payload[1]; + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_message_received: Connect response code %d\n", res)); + if (res == MQTT_CONNECT_ACCEPTED) { + /* Reset cyclic_tick when changing to connected state */ + client->cyclic_tick = 0; + client->conn_state = MQTT_CONNECTED; + /* Notify upper layer */ + if (client->connect_cb != 0) { + client->connect_cb(client, client->connect_arg, res); + } + } + } else { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_message_received: Received CONNACK in connected state\n")); + } + } else if (pkt_type == MQTT_MSG_TYPE_PINGRESP) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,( "mqtt_message_received: Received PINGRESP from server\n")); + + } else if (pkt_type == MQTT_MSG_TYPE_PUBLISH) { + u16_t payload_offset = 0; + u16_t payload_length = length; + u8_t qos = MQTT_CTL_PACKET_QOS(client->rx_buffer[0]); + + if (client->msg_idx <= MQTT_VAR_HEADER_BUFFER_LEN) { + /* Should have topic and pkt id*/ + uint8_t *topic; + uint16_t after_topic; + u8_t bkp; + u16_t topic_len = var_hdr_payload[0]; + topic_len = (topic_len << 8) + (u16_t)(var_hdr_payload[1]); + + topic = var_hdr_payload + 2; + after_topic = 2 + topic_len; + /* Check length, add one byte even for QoS 0 so that zero termination will fit */ + if ((after_topic + (qos? 2 : 1)) > length) { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_message_received: Receive buffer can not fit topic + pkt_id\n")); + goto out_disconnect; + } + + /* id for QoS 1 and 2 */ + if (qos > 0) { + client->inpub_pkt_id = ((u16_t)var_hdr_payload[after_topic] << 8) + (u16_t)var_hdr_payload[after_topic + 1]; + after_topic += 2; + } else { + client->inpub_pkt_id = 0; + } + /* Take backup of byte after topic */ + bkp = topic[topic_len]; + /* Zero terminate string */ + topic[topic_len] = 0; + /* Payload data remaining in receive buffer */ + payload_length = length - after_topic; + payload_offset = after_topic; + + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_incomming_publish: Received message with QoS %d at topic: %s, payload length %d\n", + qos, topic, remaining_length + payload_length)); + if (client->pub_cb != NULL) { + client->pub_cb(client->inpub_arg, (const char *)topic, remaining_length + payload_length); + } + /* Restore byte after topic */ + topic[topic_len] = bkp; + } + if (payload_length > 0 || remaining_length == 0) { + client->data_cb(client->inpub_arg, var_hdr_payload + payload_offset, payload_length, remaining_length == 0 ? MQTT_DATA_FLAG_LAST : 0); + /* Reply if QoS > 0 */ + if (remaining_length == 0 && qos > 0) { + /* Send PUBACK for QoS 1 or PUBREC for QoS 2 */ + u8_t resp_msg = (qos == 1) ? MQTT_MSG_TYPE_PUBACK : MQTT_MSG_TYPE_PUBREC; + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_incomming_publish: Sending publish response: %s with pkt_id: %d\n", + mqtt_msg_type_to_str(resp_msg), client->inpub_pkt_id)); + pub_ack_rec_rel_response(client, resp_msg, client->inpub_pkt_id, 0); + } + } + } else { + /* Get packet identifier */ + pkt_id = (u16_t)var_hdr_payload[0] << 8; + pkt_id |= (u16_t)var_hdr_payload[1]; + if (pkt_id == 0) { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_message_received: Got message with illegal packet identifier: 0\n")); + goto out_disconnect; + } + if (pkt_type == MQTT_MSG_TYPE_PUBREC) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_message_received: PUBREC, sending PUBREL with pkt_id: %d\n",pkt_id)); + pub_ack_rec_rel_response(client, MQTT_MSG_TYPE_PUBREL, pkt_id, 1); + + } else if (pkt_type == MQTT_MSG_TYPE_PUBREL) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_message_received: PUBREL, sending PUBCOMP response with pkt_id: %d\n",pkt_id)); + pub_ack_rec_rel_response(client, MQTT_MSG_TYPE_PUBCOMP, pkt_id, 0); + + } else if (pkt_type == MQTT_MSG_TYPE_SUBACK || pkt_type == MQTT_MSG_TYPE_UNSUBACK || + pkt_type == MQTT_MSG_TYPE_PUBCOMP || pkt_type == MQTT_MSG_TYPE_PUBACK) { + struct mqtt_request_t *r = mqtt_take_request(&client->pend_req_queue, pkt_id); + if (r != NULL) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_message_received: %s response with id %d\n", mqtt_msg_type_to_str(pkt_type), pkt_id)); + if (pkt_type == MQTT_MSG_TYPE_SUBACK) { + if (length < 3) { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_message_received: To small SUBACK packet\n")); + goto out_disconnect; + } else { + mqtt_incomming_suback(r, var_hdr_payload[2]); + } + } else if (r->cb != NULL) { + r->cb(r->arg, ERR_OK); + } + mqtt_delete_request(r); + } else { + LWIP_DEBUGF(MQTT_DEBUG_WARN,( "mqtt_message_received: Received %s reply, with wrong pkt_id: %d\n", mqtt_msg_type_to_str(pkt_type), pkt_id)); + } + } else { + LWIP_DEBUGF(MQTT_DEBUG_WARN,( "mqtt_message_received: Received unknown message type: %d\n", pkt_type)); + goto out_disconnect; + } + } + return res; +out_disconnect: + return MQTT_CONNECT_DISCONNECTED; +} + + +/** + * MQTT incoming message parser + * @param client MQTT client + * @param p PBUF chain of received data + * @return Connection status + */ +static mqtt_connection_status_t +mqtt_parse_incoming(mqtt_client_t *client, struct pbuf *p) +{ + u16_t in_offset = 0; + u32_t msg_rem_len = 0; + u8_t fixed_hdr_idx = 0; + u8_t b = 0; + + while (p->tot_len > in_offset) { + if ((fixed_hdr_idx < 2) || ((b & 0x80) != 0)) { + + if (fixed_hdr_idx < client->msg_idx) { + b = client->rx_buffer[fixed_hdr_idx]; + } else { + b = pbuf_get_at(p, in_offset++); + client->rx_buffer[client->msg_idx++] = b; + } + fixed_hdr_idx++; + + if (fixed_hdr_idx >= 2) { + msg_rem_len |= (u32_t)(b & 0x7f) << ((fixed_hdr_idx - 2) * 7); + if ((b & 0x80) == 0) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_parse_incoming: Remaining length after fixed header: %d\n", msg_rem_len)); + if (msg_rem_len == 0) { + /* Complete message with no extra headers of payload received */ + mqtt_message_received(client, fixed_hdr_idx, 0, 0); + client->msg_idx = 0; + fixed_hdr_idx = 0; + } else { + /* Bytes remaining in message */ + msg_rem_len = (msg_rem_len + fixed_hdr_idx) - client->msg_idx; + } + } + } + } else { + u16_t cpy_len, cpy_start, buffer_space; + + cpy_start = (client->msg_idx - fixed_hdr_idx) % (MQTT_VAR_HEADER_BUFFER_LEN - fixed_hdr_idx) + fixed_hdr_idx; + + /* Allow to copy the lesser one of available length in input data or bytes remaining in message */ + cpy_len = (u16_t)LWIP_MIN((u16_t)(p->tot_len - in_offset), msg_rem_len); + + /* Limit to available space in buffer */ + buffer_space = MQTT_VAR_HEADER_BUFFER_LEN - cpy_start; + if (cpy_len > buffer_space) { + cpy_len = buffer_space; + } + pbuf_copy_partial(p, client->rx_buffer+cpy_start, cpy_len, in_offset); + + /* Advance get and put indexes */ + client->msg_idx += cpy_len; + in_offset += cpy_len; + msg_rem_len -= cpy_len; + + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_parse_incoming: msg_idx: %d, cpy_len: %d, remaining %d\n", client->msg_idx, cpy_len, msg_rem_len)); + if (msg_rem_len == 0 || cpy_len == buffer_space) { + /* Whole message received or buffer is full */ + mqtt_connection_status_t res = mqtt_message_received(client, fixed_hdr_idx, (cpy_start + cpy_len) - fixed_hdr_idx, msg_rem_len); + if (res != MQTT_CONNECT_ACCEPTED) { + return res; + } + if (msg_rem_len == 0) { + /* Reset parser state */ + client->msg_idx = 0; + /* msg_tot_len = 0; */ + fixed_hdr_idx = 0; + } + } + } + } + return MQTT_CONNECT_ACCEPTED; +} + + +/** + * TCP received callback function. @see tcp_recv_fn + * @param arg MQTT client + * @param p PBUF chain of received data + * @param err Passed as return value if not ERR_OK + * @return ERR_OK or err passed into callback + */ +static err_t +mqtt_tcp_recv_cb(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err) +{ + mqtt_client_t *client = (mqtt_client_t *)arg; + LWIP_ASSERT("mqtt_tcp_recv_cb: client != NULL", client != NULL); + LWIP_ASSERT("mqtt_tcp_recv_cb: client->conn == pcb", client->conn == pcb); + + if (p == NULL) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_tcp_recv_cb: Recv pbuf=NULL, remote has closed connection\n")); + mqtt_close(client, MQTT_CONNECT_DISCONNECTED); + } else { + mqtt_connection_status_t res; + if (err != ERR_OK) { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_tcp_recv_cb: Recv err=%d\n", err)); + pbuf_free(p); + return err; + } + + /* Tell remote that data has been received */ + tcp_recved(pcb, p->tot_len); + res = mqtt_parse_incoming(client, p); + pbuf_free(p); + + if (res != MQTT_CONNECT_ACCEPTED) { + mqtt_close(client, res); + } + /* If keep alive functionality is used */ + if (client->keep_alive != 0) { + /* Reset server alive watchdog */ + client->server_watchdog = 0; + } + + } + return ERR_OK; +} + + +/** + * TCP data sent callback function. @see tcp_sent_fn + * @param arg MQTT client + * @param tpcb TCP connection handle + * @param len Number of bytes sent + * @return ERR_OK + */ +static err_t +mqtt_tcp_sent_cb(void *arg, struct tcp_pcb *tpcb, u16_t len) +{ + mqtt_client_t *client = (mqtt_client_t *)arg; + + LWIP_UNUSED_ARG(tpcb); + LWIP_UNUSED_ARG(len); + + if (client->conn_state == MQTT_CONNECTED) { + struct mqtt_request_t *r; + + /* Reset keep-alive send timer and server watchdog */ + client->cyclic_tick = 0; + client->server_watchdog = 0; + /* QoS 0 publish has no response from server, so call its callbacks here */ + while ((r = mqtt_take_request(&client->pend_req_queue, 0)) != NULL) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_tcp_sent_cb: Calling QoS 0 publish complete callback\n")); + if (r->cb != NULL) { + r->cb(r->arg, ERR_OK); + } + mqtt_delete_request(r); + } + /* Try send any remaining buffers from output queue */ + mqtt_output_send(&client->output, client->conn); + } + return ERR_OK; +} + +/** + * TCP error callback function. @see tcp_err_fn + * @param arg MQTT client + * @param err Error encountered + */ +static void +mqtt_tcp_err_cb(void *arg, err_t err) +{ + mqtt_client_t *client = (mqtt_client_t *)arg; + LWIP_UNUSED_ARG(err); /* only used for debug output */ + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_tcp_err_cb: TCP error callback: error %d, arg: %p\n", err, arg)); + LWIP_ASSERT("mqtt_tcp_err_cb: client != NULL", client != NULL); + /* Set conn to null before calling close as pcb is already deallocated*/ + client->conn = 0; + mqtt_close(client, MQTT_CONNECT_DISCONNECTED); +} + +/** + * TCP poll callback function. @see tcp_poll_fn + * @param arg MQTT client + * @param tpcb TCP connection handle + * @return err ERR_OK + */ +static err_t +mqtt_tcp_poll_cb(void *arg, struct tcp_pcb *tpcb) +{ + mqtt_client_t *client = (mqtt_client_t *)arg; + if (client->conn_state == MQTT_CONNECTED) { + /* Try send any remaining buffers from output queue */ + mqtt_output_send(&client->output, tpcb); + } + return ERR_OK; +} + +/** + * TCP connect callback function. @see tcp_connected_fn + * @param arg MQTT client + * @param err Always ERR_OK, mqtt_tcp_err_cb is called in case of error + * @return ERR_OK + */ +static err_t +mqtt_tcp_connect_cb(void *arg, struct tcp_pcb *tpcb, err_t err) +{ + mqtt_client_t* client = (mqtt_client_t *)arg; + + if (err != ERR_OK) { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_tcp_connect_cb: TCP connect error %d\n", err)); + return err; + } + + /* Initiate receiver state */ + client->msg_idx = 0; + + /* Setup TCP callbacks */ + tcp_recv(tpcb, mqtt_tcp_recv_cb); + tcp_sent(tpcb, mqtt_tcp_sent_cb); + tcp_poll(tpcb, mqtt_tcp_poll_cb, 2); + + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_tcp_connect_cb: TCP connection established to server\n")); + /* Enter MQTT connect state */ + client->conn_state = MQTT_CONNECTING; + + /* Start cyclic timer */ + sys_timeout(MQTT_CYCLIC_TIMER_INTERVAL*1000, mqtt_cyclic_timer, client); + client->cyclic_tick = 0; + + /* Start transmission from output queue, connect message is the first one out*/ + mqtt_output_send(&client->output, client->conn); + + return ERR_OK; +} + + + +/*---------------------------------------------------------------------------------------------------- */ +/* Public API */ + + +/** + * @ingroup mqtt + * MQTT publish function. + * @param client MQTT client + * @param topic Publish topic string + * @param payload Data to publish (NULL is allowed) + * @param payload_length: Length of payload (0 is allowed) + * @param qos Quality of service, 0 1 or 2 + * @param retain MQTT retain flag + * @param cb Callback to call when publish is complete or has timed out + * @param arg User supplied argument to publish callback + * @return ERR_OK if successful + * ERR_CONN if client is disconnected + * ERR_MEM if short on memory + */ +err_t +mqtt_publish(mqtt_client_t *client, const char *topic, const void *payload, u16_t payload_length, u8_t qos, u8_t retain, + mqtt_request_cb_t cb, void *arg) +{ + struct mqtt_request_t *r; + u16_t pkt_id; + size_t topic_strlen; + size_t total_len; + u16_t topic_len; + u16_t remaining_length; + + LWIP_ASSERT("mqtt_publish: client != NULL", client); + LWIP_ASSERT("mqtt_publish: topic != NULL", topic); + LWIP_ERROR("mqtt_publish: TCP disconnected", (client->conn_state != TCP_DISCONNECTED), return ERR_CONN); + + topic_strlen = strlen(topic); + LWIP_ERROR("mqtt_publish: topic length overflow", (topic_strlen <= (0xFFFF - 2)), return ERR_ARG); + topic_len = (u16_t)topic_strlen; + total_len = 2 + topic_len + payload_length; + LWIP_ERROR("mqtt_publish: total length overflow", (total_len <= 0xFFFF), return ERR_ARG); + remaining_length = (u16_t)total_len; + + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_publish: Publish with payload length %d to topic \"%s\"\n", payload_length, topic)); + + if (qos > 0) { + remaining_length += 2; + /* Generate pkt_id id for QoS1 and 2 */ + pkt_id = msg_generate_packet_id(client); + } else { + /* Use reserved value pkt_id 0 for QoS 0 in request handle */ + pkt_id = 0; + } + + r = mqtt_create_request(client->req_list, pkt_id, cb, arg); + if (r == NULL) { + return ERR_MEM; + } + + if (mqtt_output_check_space(&client->output, remaining_length) == 0) { + mqtt_delete_request(r); + return ERR_MEM; + } + /* Append fixed header */ + mqtt_output_append_fixed_header(&client->output, MQTT_MSG_TYPE_PUBLISH, 0, qos, retain, remaining_length); + + /* Append Topic */ + mqtt_output_append_string(&client->output, topic, topic_len); + + /* Append packet if for QoS 1 and 2*/ + if (qos > 0) { + mqtt_output_append_u16(&client->output, pkt_id); + } + + /* Append optional publish payload */ + if ((payload != NULL) && (payload_length > 0)) { + mqtt_output_append_buf(&client->output, payload, payload_length); + } + + mqtt_append_request(&client->pend_req_queue, r); + mqtt_output_send(&client->output, client->conn); + return ERR_OK; +} + + +/** + * @ingroup mqtt + * MQTT subscribe/unsubscribe function. + * @param client MQTT client + * @param topic topic to subscribe to + * @param qos Quality of service, 0 1 or 2 (only used for subscribe) + * @param cb Callback to call when subscribe/unsubscribe reponse is received + * @param arg User supplied argument to publish callback + * @param sub 1 for subscribe, 0 for unsubscribe + * @return ERR_OK if successful, @see err_t enum for other results + */ +err_t +mqtt_sub_unsub(mqtt_client_t *client, const char *topic, u8_t qos, mqtt_request_cb_t cb, void *arg, u8_t sub) +{ + size_t topic_strlen; + size_t total_len; + u16_t topic_len; + u16_t remaining_length; + u16_t pkt_id; + struct mqtt_request_t *r; + + LWIP_ASSERT("mqtt_sub_unsub: client != NULL", client); + LWIP_ASSERT("mqtt_sub_unsub: topic != NULL", topic); + + topic_strlen = strlen(topic); + LWIP_ERROR("mqtt_sub_unsub: topic length overflow", (topic_strlen <= (0xFFFF - 2)), return ERR_ARG); + topic_len = (u16_t)topic_strlen; + /* Topic string, pkt_id, qos for subscribe */ + total_len = topic_len + 2 + 2 + (sub != 0); + LWIP_ERROR("mqtt_sub_unsub: total length overflow", (total_len <= 0xFFFF), return ERR_ARG); + remaining_length = (u16_t)total_len; + + LWIP_ASSERT("mqtt_sub_unsub: qos < 3", qos < 3); + if (client->conn_state == TCP_DISCONNECTED) { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_sub_unsub: Can not (un)subscribe in disconnected state\n")); + return ERR_CONN; + } + + pkt_id = msg_generate_packet_id(client); + r = mqtt_create_request(client->req_list, pkt_id, cb, arg); + if (r == NULL) { + return ERR_MEM; + } + + if (mqtt_output_check_space(&client->output, remaining_length) == 0) { + mqtt_delete_request(r); + return ERR_MEM; + } + + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_sub_unsub: Client (un)subscribe to topic \"%s\", id: %d\n", topic, pkt_id)); + + mqtt_output_append_fixed_header(&client->output, sub ? MQTT_MSG_TYPE_SUBSCRIBE : MQTT_MSG_TYPE_UNSUBSCRIBE, 0, 1, 0, remaining_length); + /* Packet id */ + mqtt_output_append_u16(&client->output, pkt_id); + /* Topic */ + mqtt_output_append_string(&client->output, topic, topic_len); + /* QoS */ + if (sub != 0) { + mqtt_output_append_u8(&client->output, LWIP_MIN(qos, 2)); + } + + mqtt_append_request(&client->pend_req_queue, r); + mqtt_output_send(&client->output, client->conn); + return ERR_OK; +} + + +/** + * @ingroup mqtt + * Set callback to handle incoming publish requests from server + * @param client MQTT client + * @param pub_cb Callback invoked when publish starts, contain topic and total length of payload + * @param data_cb Callback for each fragment of payload that arrives + * @param arg User supplied argument to both callbacks + */ +void +mqtt_set_inpub_callback(mqtt_client_t *client, mqtt_incoming_publish_cb_t pub_cb, + mqtt_incoming_data_cb_t data_cb, void *arg) +{ + LWIP_ASSERT("mqtt_set_inpub_callback: client != NULL", client != NULL); + client->data_cb = data_cb; + client->pub_cb = pub_cb; + client->inpub_arg = arg; +} + +/** + * @ingroup mqtt + * Create a new MQTT client instance + * @return Pointer to instance on success, NULL otherwise + */ +mqtt_client_t * +mqtt_client_new(void) +{ + mqtt_client_t *client = (mqtt_client_t *)mem_malloc(sizeof(mqtt_client_t)); + if (client != NULL) { + memset(client, 0, sizeof(mqtt_client_t)); + } + return client; +} + + +/** + * @ingroup mqtt + * Connect to MQTT server + * @param client MQTT client + * @param ip_addr Server IP + * @param port Server port + * @param cb Connection state change callback + * @param arg User supplied argument to connection callback + * @param client_info Client identification and connection options + * @return ERR_OK if successful, @see err_t enum for other results + */ +err_t +mqtt_client_connect(mqtt_client_t *client, const ip_addr_t *ip_addr, u16_t port, mqtt_connection_cb_t cb, void *arg, + const struct mqtt_connect_client_info_t *client_info) +{ + err_t err; + size_t len; + u16_t client_id_length; + /* Length is the sum of 2+"MQTT", protocol level, flags and keep alive */ + u16_t remaining_length = 2 + 4 + 1 + 1 + 2; + u8_t flags = 0, will_topic_len = 0, will_msg_len = 0; + + LWIP_ASSERT("mqtt_client_connect: client != NULL", client != NULL); + LWIP_ASSERT("mqtt_client_connect: ip_addr != NULL", ip_addr != NULL); + LWIP_ASSERT("mqtt_client_connect: client_info != NULL", client_info != NULL); + LWIP_ASSERT("mqtt_client_connect: client_info->client_id != NULL", client_info->client_id != NULL); + + if (client->conn_state != TCP_DISCONNECTED) { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_client_connect: Already connected\n")); + return ERR_ISCONN; + } + + /* Wipe clean */ + memset(client, 0, sizeof(mqtt_client_t)); + client->connect_arg = arg; + client->connect_cb = cb; + client->keep_alive = client_info->keep_alive; + mqtt_init_requests(client->req_list); + + /* Build connect message */ + if (client_info->will_topic != NULL && client_info->will_msg != NULL) { + flags |= MQTT_CONNECT_FLAG_WILL; + flags |= (client_info->will_qos & 3) << 3; + if (client_info->will_retain) { + flags |= MQTT_CONNECT_FLAG_WILL_RETAIN; + } + len = strlen(client_info->will_topic); + LWIP_ERROR("mqtt_client_connect: client_info->will_topic length overflow", len <= 0xFF, return ERR_VAL); + LWIP_ERROR("mqtt_client_connect: client_info->will_topic length must be > 0", len > 0, return ERR_VAL); + will_topic_len = (u8_t)len; + len = strlen(client_info->will_msg); + LWIP_ERROR("mqtt_client_connect: client_info->will_msg length overflow", len <= 0xFF, return ERR_VAL); + will_msg_len = (u8_t)len; + len = remaining_length + 2 + will_topic_len + 2 + will_msg_len; + LWIP_ERROR("mqtt_client_connect: remaining_length overflow", len <= 0xFFFF, return ERR_VAL); + remaining_length = (u16_t)len; + } + + /* Don't complicate things, always connect using clean session */ + flags |= MQTT_CONNECT_FLAG_CLEAN_SESSION; + + len = strlen(client_info->client_id); + LWIP_ERROR("mqtt_client_connect: client_info->client_id length overflow", len <= 0xFFFF, return ERR_VAL); + client_id_length = (u16_t)len; + len = remaining_length + 2 + client_id_length; + LWIP_ERROR("mqtt_client_connect: remaining_length overflow", len <= 0xFFFF, return ERR_VAL); + remaining_length = (u16_t)len; + + if (mqtt_output_check_space(&client->output, remaining_length) == 0) { + return ERR_MEM; + } + + client->conn = tcp_new(); + if (client->conn == NULL) { + return ERR_MEM; + } + + /* Set arg pointer for callbacks */ + tcp_arg(client->conn, client); + /* Any local address, pick random local port number */ + err = tcp_bind(client->conn, IP_ADDR_ANY, 0); + if (err != ERR_OK) { + LWIP_DEBUGF(MQTT_DEBUG_WARN,("mqtt_client_connect: Error binding to local ip/port, %d\n", err)); + goto tcp_fail; + } + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_client_connect: Connecting to host: %s at port:%"U16_F"\n", ipaddr_ntoa(ip_addr), port)); + + /* Connect to server */ + err = tcp_connect(client->conn, ip_addr, port, mqtt_tcp_connect_cb); + if (err != ERR_OK) { + LWIP_DEBUGF(MQTT_DEBUG_TRACE,("mqtt_client_connect: Error connecting to remote ip/port, %d\n", err)); + goto tcp_fail; + } + /* Set error callback */ + tcp_err(client->conn, mqtt_tcp_err_cb); + client->conn_state = TCP_CONNECTING; + + /* Append fixed header */ + mqtt_output_append_fixed_header(&client->output, MQTT_MSG_TYPE_CONNECT, 0, 0, 0, remaining_length); + /* Append Protocol string */ + mqtt_output_append_string(&client->output, "MQTT", 4); + /* Append Protocol level */ + mqtt_output_append_u8(&client->output, 4); + /* Append connect flags */ + mqtt_output_append_u8(&client->output, flags); + /* Append keep-alive */ + mqtt_output_append_u16(&client->output, client_info->keep_alive); + /* Append client id */ + mqtt_output_append_string(&client->output, client_info->client_id, client_id_length); + /* Append will message if used */ + if ((flags & MQTT_CONNECT_FLAG_WILL) != 0) { + mqtt_output_append_string(&client->output, client_info->will_topic, will_topic_len); + mqtt_output_append_string(&client->output, client_info->will_msg, will_msg_len); + } + return ERR_OK; + +tcp_fail: + tcp_abort(client->conn); + client->conn = NULL; + return err; +} + + +/** + * @ingroup mqtt + * Disconnect from MQTT server + * @param client MQTT client + */ +void +mqtt_disconnect(mqtt_client_t *client) +{ + LWIP_ASSERT("mqtt_disconnect: client != NULL", client); + /* If connection in not already closed */ + if (client->conn_state != TCP_DISCONNECTED) { + /* Set conn_state before calling mqtt_close to prevent callback from being called */ + client->conn_state = TCP_DISCONNECTED; + mqtt_close(client, (mqtt_connection_status_t)0); + } +} + +/** + * @ingroup mqtt + * Check connection with server + * @param client MQTT client + * @return 1 if connected to server, 0 otherwise + */ +u8_t +mqtt_client_is_connected(mqtt_client_t *client) +{ + LWIP_ASSERT("mqtt_client_is_connected: client != NULL", client); + return client->conn_state == MQTT_CONNECTED; +} + +#endif /* LWIP_TCP && LWIP_CALLBACK_API */ |