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ESPAsyncTCP.cpp
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ESPAsyncTCP.cpp
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/*
Asynchronous TCP library for Espressif MCUs
Copyright (c) 2016 Hristo Gochkov. All rights reserved.
This file is part of the esp8266 core for Arduino environment.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/*
Changes for July 2019
The operator "new ..." was changed to "new (std::nothrow) ...", which will
return NULL when the heap is out of memory. Without the change "soft WDT"
was the result, starting with Arduino ESP8266 Core 2.5.0. (Note, RE:"soft
WDT" - the error reporting may improve with core 2.6.) With proir core
versions the library appears to work fine.
ref: https://github.com/esp8266/Arduino/issues/6269#issue-464978944
To support newer lwIP versions and buffer models. All references to 1460
were replaced with TCP_MSS. If TCP_MSS is not defined (exp. 1.4v lwIP)
1460 is assumed.
The ESPAsyncTCP library should build for Arduino ESP8266 Core releases:
2.3.0, 2.4.1, 2.4.2, 2.5.1, 2.5.2. It may still build with core versions
2.4.0 and 2.5.0. I did not do any regression testing with these, since
they had too many issues and were quickly superseded.
lwIP tcp_err() callback often resulted in crashes. The problem was a
tcp_err() would come in, while processing a send or receive in the
forground. The tcp_err() callback would be passed down to a client's
registered disconnect CB. A common problem with SyncClient and other
modules as well as some client code was: the freeing of ESPAsyncTCP
AsyncClient objects via disconnect CB handlers while the library was
waiting for an operstion to finished. Attempts to access bad pointers
followed. For SyncClient this commonly occured during a call to delay().
On return to SyncClient _client was invalid. Also the problem described by
issue #94 also surfaced
Use of tcp_abort() required some very special handling and was very
challenging to make work without changing client API. ERR_ABRT can only be
used once on a return to lwIP for a given connection and since the
AsyncClient structure was sometimes deleted before returning to lwIP, the
state tracking became tricky. While ugly, a global variable for this
seemed to work; however, I abanded it when I saw a possible
reentrancy/concurrency issue. After several approaches I settled the
problem by creating "class ACErrorTracker" to manage the issue.
Additional Async Client considerations:
The client sketch must always test if the connection is still up at loop()
entry and after the return of any function call, that may have done a
delay() or yield() or any ESPAsyncTCP library family call. For example,
the connection could be lost during a call to _client->write(...). Client
sketches that delete _client as part of their onDisconnect() handler must
be very careful as _client will become invalid after calls to delay(),
yield(), etc.
*/
#include "Arduino.h"
#include "ESPAsyncTCP.h"
extern "C"{
#include "lwip/opt.h"
#include "lwip/tcp.h"
#include "lwip/inet.h"
#include "lwip/dns.h"
#include "lwip/init.h"
}
#include <tcp_axtls.h>
/*
Async Client Error Return Tracker
*/
// Assumption: callbacks are never called with err == ERR_ABRT; however,
// they may return ERR_ABRT.
ACErrorTracker::ACErrorTracker(AsyncClient *c):
_client(c)
, _close_error(ERR_OK)
, _errored(EE_OK)
#ifdef DEBUG_MORE
, _error_event_cb(NULL)
, _error_event_cb_arg(NULL)
#endif
{}
#ifdef DEBUG_MORE
/**
* This is not necessary, but a start at gathering some statistics on
* errored out connections. Used from AsyncServer.
*/
void ACErrorTracker::onErrorEvent(AsNotifyHandler cb, void *arg) {
_error_event_cb = cb;
_error_event_cb_arg = arg;
}
#endif
void ACErrorTracker::setCloseError(err_t e) {
if (e != ERR_OK)
ASYNC_TCP_DEBUG("setCloseError() to: %s(%ld)\n", _client->errorToString(e), e);
if(_errored == EE_OK)
_close_error = e;
}
/**
* Called mainly by callback routines, called when err is not ERR_OK.
* This prevents the possiblity of aborting an already errored out
* connection.
*/
void ACErrorTracker::setErrored(size_t errorEvent){
if(EE_OK == _errored)
_errored = errorEvent;
#ifdef DEBUG_MORE
if (_error_event_cb)
_error_event_cb(_error_event_cb_arg, errorEvent);
#endif
}
/**
* Used by callback functions only. Used for proper ERR_ABRT return value
* reporting. ERR_ABRT is only reported/returned once; thereafter ERR_OK
* is always returned.
*/
err_t ACErrorTracker::getCallbackCloseError(void){
if (EE_OK != _errored)
return ERR_OK;
if (ERR_ABRT == _close_error)
setErrored(EE_ABORTED);
return _close_error;
}
/*
Async TCP Client
*/
#if DEBUG_ESP_ASYNC_TCP
static size_t _connectionCount=0;
#endif
#if ASYNC_TCP_SSL_ENABLED
AsyncClient::AsyncClient(tcp_pcb* pcb, SSL_CTX * ssl_ctx):
#else
AsyncClient::AsyncClient(tcp_pcb* pcb):
#endif
_connect_cb(0)
, _connect_cb_arg(0)
, _discard_cb(0)
, _discard_cb_arg(0)
, _sent_cb(0)
, _sent_cb_arg(0)
, _error_cb(0)
, _error_cb_arg(0)
, _recv_cb(0)
, _recv_cb_arg(0)
, _pb_cb(0)
, _pb_cb_arg(0)
, _timeout_cb(0)
, _timeout_cb_arg(0)
, _poll_cb(0)
, _poll_cb_arg(0)
, _pcb_busy(false)
#if ASYNC_TCP_SSL_ENABLED
, _pcb_secure(false)
, _handshake_done(true)
#endif
, _pcb_sent_at(0)
, _close_pcb(false)
, _ack_pcb(true)
, _tx_unacked_len(0)
, _tx_acked_len(0)
, _tx_unsent_len(0)
, _rx_ack_len(0)
, _rx_last_packet(0)
, _rx_since_timeout(0)
, _ack_timeout(ASYNC_MAX_ACK_TIME)
, _connect_port(0)
, _recv_pbuf_flags(0)
, _errorTracker(NULL)
, prev(NULL)
, next(NULL)
{
_pcb = pcb;
if(_pcb){
_rx_last_packet = millis();
tcp_setprio(_pcb, TCP_PRIO_MIN);
tcp_arg(_pcb, this);
tcp_recv(_pcb, &_s_recv);
tcp_sent(_pcb, &_s_sent);
tcp_err(_pcb, &_s_error);
tcp_poll(_pcb, &_s_poll, 1);
#if ASYNC_TCP_SSL_ENABLED
if(ssl_ctx){
if(tcp_ssl_new_server(_pcb, ssl_ctx) < 0){
_close();
return;
}
tcp_ssl_arg(_pcb, this);
tcp_ssl_data(_pcb, &_s_data);
tcp_ssl_handshake(_pcb, &_s_handshake);
tcp_ssl_err(_pcb, &_s_ssl_error);
_pcb_secure = true;
_handshake_done = false;
}
#endif
}
_errorTracker = std::make_shared<ACErrorTracker>(this);
#if DEBUG_ESP_ASYNC_TCP
_errorTracker->setConnectionId(++_connectionCount);
#endif
}
AsyncClient::~AsyncClient(){
if(_pcb)
_close();
_errorTracker->clearClient();
}
inline void clearTcpCallbacks(tcp_pcb* pcb){
tcp_arg(pcb, NULL);
tcp_sent(pcb, NULL);
tcp_recv(pcb, NULL);
tcp_err(pcb, NULL);
tcp_poll(pcb, NULL, 0);
}
#if ASYNC_TCP_SSL_ENABLED
bool AsyncClient::connect(IPAddress ip, uint16_t port, bool secure){
#else
bool AsyncClient::connect(IPAddress ip, uint16_t port){
#endif
if (_pcb) //already connected
return false;
ip_addr_t addr;
addr.addr = ip;
#if LWIP_VERSION_MAJOR == 1
netif* interface = ip_route(&addr);
if (!interface){ //no route to host
return false;
}
#endif
tcp_pcb* pcb = tcp_new();
if (!pcb){ //could not allocate pcb
return false;
}
tcp_setprio(pcb, TCP_PRIO_MIN);
#if ASYNC_TCP_SSL_ENABLED
_pcb_secure = secure;
_handshake_done = !secure;
#endif
tcp_arg(pcb, this);
tcp_err(pcb, &_s_error);
size_t err = tcp_connect(pcb, &addr, port,(tcp_connected_fn)&_s_connected);
return (ERR_OK == err);
}
#if ASYNC_TCP_SSL_ENABLED
bool AsyncClient::connect(const char* host, uint16_t port, bool secure){
#else
bool AsyncClient::connect(const char* host, uint16_t port){
#endif
ip_addr_t addr;
err_t err = dns_gethostbyname(host, &addr, (dns_found_callback)&_s_dns_found, this);
if(err == ERR_OK) {
#if ASYNC_TCP_SSL_ENABLED
return connect(IPAddress(addr.addr), port, secure);
#else
return connect(IPAddress(addr.addr), port);
#endif
} else if(err == ERR_INPROGRESS) {
#if ASYNC_TCP_SSL_ENABLED
_pcb_secure = secure;
_handshake_done = !secure;
#endif
_connect_port = port;
return true;
}
return false;
}
AsyncClient& AsyncClient::operator=(const AsyncClient& other){
if (_pcb) {
ASYNC_TCP_DEBUG("operator=[%u]: Abandoned _pcb(0x%" PRIXPTR ") forced close.\n", getConnectionId(), uintptr_t(_pcb));
_close();
}
_errorTracker = other._errorTracker;
// I am confused when "other._pcb" falls out of scope the destructor will
// close it? TODO: Look to see where this is used and how it might work.
_pcb = other._pcb;
if (_pcb) {
_rx_last_packet = millis();
tcp_setprio(_pcb, TCP_PRIO_MIN);
tcp_arg(_pcb, this);
tcp_recv(_pcb, &_s_recv);
tcp_sent(_pcb, &_s_sent);
tcp_err(_pcb, &_s_error);
tcp_poll(_pcb, &_s_poll, 1);
#if ASYNC_TCP_SSL_ENABLED
if(tcp_ssl_has(_pcb)){
_pcb_secure = true;
_handshake_done = false;
tcp_ssl_arg(_pcb, this);
tcp_ssl_data(_pcb, &_s_data);
tcp_ssl_handshake(_pcb, &_s_handshake);
tcp_ssl_err(_pcb, &_s_ssl_error);
} else {
_pcb_secure = false;
_handshake_done = true;
}
#endif
}
return *this;
}
bool AsyncClient::operator==(const AsyncClient &other) {
return (_pcb != NULL && other._pcb != NULL && (_pcb->remote_ip.addr == other._pcb->remote_ip.addr) && (_pcb->remote_port == other._pcb->remote_port));
}
void AsyncClient::abort(){
// Notes:
// 1) _pcb is set to NULL, so we cannot call tcp_abort() more than once.
// 2) setCloseError(ERR_ABRT) is only done here!
// 3) Using this abort() function guarantees only one tcp_abort() call is
// made and only one CB returns with ERR_ABORT.
// 4) After abort() is called from _close(), no callbacks with an err
// parameter will be called. eg. _recv(), _error(), _connected().
// _close() will reset there CB handlers before calling.
// 5) A callback to _error(), will set _pcb to NULL, thus avoiding the
// of a 2nd call to tcp_abort().
// 6) Callbacks to _recv() or _connected() with err set, will result in _pcb
// set to NULL. Thus, preventing possible calls later to tcp_abort().
if(_pcb) {
tcp_abort(_pcb);
_pcb = NULL;
setCloseError(ERR_ABRT);
}
return;
}
void AsyncClient::close(bool now){
if(_pcb)
tcp_recved(_pcb, _rx_ack_len);
if(now)
_close();
else
_close_pcb = true;
}
void AsyncClient::stop() {
close(false);
}
bool AsyncClient::free(){
if(!_pcb)
return true;
if(_pcb->state == 0 || _pcb->state > 4)
return true;
return false;
}
size_t AsyncClient::write(const char* data) {
if(data == NULL)
return 0;
return write(data, strlen(data));
}
size_t AsyncClient::write(const char* data, size_t size, uint8_t apiflags) {
size_t will_send = add(data, size, apiflags);
if(!will_send || !send())
return 0;
return will_send;
}
size_t AsyncClient::add(const char* data, size_t size, uint8_t apiflags) {
if(!_pcb || size == 0 || data == NULL)
return 0;
size_t room = space();
if(!room)
return 0;
#if ASYNC_TCP_SSL_ENABLED
if(_pcb_secure){
int sent = tcp_ssl_write(_pcb, (uint8_t*)data, size);
if(sent >= 0){
_tx_unacked_len += sent;
return sent;
}
_close();
return 0;
}
#endif
size_t will_send = (room < size) ? room : size;
err_t err = tcp_write(_pcb, data, will_send, apiflags);
if(err != ERR_OK) {
ASYNC_TCP_DEBUG("_add[%u]: tcp_write() returned err: %s(%ld)\n", getConnectionId(), errorToString(err), err);
return 0;
}
_tx_unsent_len += will_send;
return will_send;
}
bool AsyncClient::send(){
#if ASYNC_TCP_SSL_ENABLED
if(_pcb_secure)
return true;
#endif
err_t err = tcp_output(_pcb);
if(err == ERR_OK){
_pcb_busy = true;
_pcb_sent_at = millis();
_tx_unacked_len += _tx_unsent_len;
_tx_unsent_len = 0;
return true;
}
ASYNC_TCP_DEBUG("send[%u]: tcp_output() returned err: %s(%ld)", getConnectionId(), errorToString(err), err);
_tx_unsent_len = 0;
return false;
}
size_t AsyncClient::ack(size_t len){
if(len > _rx_ack_len)
len = _rx_ack_len;
if(len)
tcp_recved(_pcb, len);
_rx_ack_len -= len;
return len;
}
// Private Callbacks
void AsyncClient::_connected(std::shared_ptr<ACErrorTracker>& errorTracker, void* pcb, err_t err){
//(void)err; // LWIP v1.4 appears to always call with ERR_OK
// Documentation for 2.1.0 also says:
// "err - An unused error code, always ERR_OK currently ;-)"
// https://www.nongnu.org/lwip/2_1_x/tcp_8h.html#a939867106bd492caf2d85852fb7f6ae8
// Based on that wording and emoji lets just handle it now.
// After all, the API does allow for an err != ERR_OK.
if(NULL == pcb || ERR_OK != err) {
ASYNC_TCP_DEBUG("_connected[%u]:%s err: %s(%ld)\n", errorTracker->getConnectionId(), ((NULL == pcb) ? " NULL == pcb!," : ""), errorToString(err), err);
errorTracker->setCloseError(err);
errorTracker->setErrored(EE_CONNECTED_CB);
_pcb = reinterpret_cast<tcp_pcb*>(pcb);
if (_pcb)
clearTcpCallbacks(_pcb);
_pcb = NULL;
_error(err);
return;
}
_pcb = reinterpret_cast<tcp_pcb*>(pcb);
if(_pcb){
_pcb_busy = false;
_rx_last_packet = millis();
tcp_setprio(_pcb, TCP_PRIO_MIN);
tcp_recv(_pcb, &_s_recv);
tcp_sent(_pcb, &_s_sent);
tcp_poll(_pcb, &_s_poll, 1);
#if ASYNC_TCP_SSL_ENABLED
if(_pcb_secure){
if(tcp_ssl_new_client(_pcb) < 0){
_close();
return;
}
tcp_ssl_arg(_pcb, this);
tcp_ssl_data(_pcb, &_s_data);
tcp_ssl_handshake(_pcb, &_s_handshake);
tcp_ssl_err(_pcb, &_s_ssl_error);
}
}
if(!_pcb_secure && _connect_cb)
#else
}
if(_connect_cb)
#endif
_connect_cb(_connect_cb_arg, this);
return;
}
void AsyncClient::_close(){
if(_pcb) {
#if ASYNC_TCP_SSL_ENABLED
if(_pcb_secure){
tcp_ssl_free(_pcb);
}
#endif
clearTcpCallbacks(_pcb);
err_t err = tcp_close(_pcb);
if(ERR_OK == err) {
setCloseError(err);
} else {
ASYNC_TCP_DEBUG("_close[%u]: abort() called for AsyncClient 0x%" PRIXPTR "\n", getConnectionId(), uintptr_t(this));
abort();
}
_pcb = NULL;
if(_discard_cb)
_discard_cb(_discard_cb_arg, this);
}
return;
}
void AsyncClient::_error(err_t err) {
ASYNC_TCP_DEBUG("_error[%u]:%s err: %s(%ld)\n", getConnectionId(), ((NULL == _pcb) ? " NULL == _pcb!," : ""), errorToString(err), err);
if(_pcb){
#if ASYNC_TCP_SSL_ENABLED
if(_pcb_secure){
tcp_ssl_free(_pcb);
}
#endif
// At this callback _pcb is possible already freed. Thus, no calls are
// made to set to NULL other callbacks.
_pcb = NULL;
}
if(_error_cb)
_error_cb(_error_cb_arg, this, err);
if(_discard_cb)
_discard_cb(_discard_cb_arg, this);
}
#if ASYNC_TCP_SSL_ENABLED
void AsyncClient::_ssl_error(int8_t err){
if(_error_cb)
_error_cb(_error_cb_arg, this, err+64);
}
#endif
void AsyncClient::_sent(std::shared_ptr<ACErrorTracker>& errorTracker, tcp_pcb* pcb, uint16_t len) {
(void)pcb;
#if ASYNC_TCP_SSL_ENABLED
if (_pcb_secure && !_handshake_done)
return;
#endif
_rx_last_packet = millis();
_tx_unacked_len -= len;
_tx_acked_len += len;
ASYNC_TCP_DEBUG("_sent[%u]: %4u, unacked=%4u, acked=%4u, space=%4u\n", errorTracker->getConnectionId(), len, _tx_unacked_len, _tx_acked_len, space());
if(_tx_unacked_len == 0){
_pcb_busy = false;
errorTracker->setCloseError(ERR_OK);
if(_sent_cb) {
_sent_cb(_sent_cb_arg, this, _tx_acked_len, (millis() - _pcb_sent_at));
if(!errorTracker->hasClient())
return;
}
_tx_acked_len = 0;
}
return;
}
void AsyncClient::_recv(std::shared_ptr<ACErrorTracker>& errorTracker, tcp_pcb* pcb, pbuf* pb, err_t err) {
// While lwIP v1.4 appears to always call with ERR_OK, 2.x lwIP may present
// a non-ERR_OK value.
// https://www.nongnu.org/lwip/2_1_x/tcp_8h.html#a780cfac08b02c66948ab94ea974202e8
if(NULL == pcb || ERR_OK != err){
ASYNC_TCP_DEBUG("_recv[%u]:%s err: %s(%ld)\n", errorTracker->getConnectionId(), ((NULL == pcb) ? " NULL == pcb!," : ""), errorToString(err), err);
ASYNC_TCP_ASSERT(ERR_ABRT != err);
errorTracker->setCloseError(err);
errorTracker->setErrored(EE_RECV_CB);
_pcb = pcb;
if(_pcb)
clearTcpCallbacks(_pcb);
_pcb = NULL;
// I think we are safe from being called from an interrupt context.
// Best Hint that calling _error() is safe:
// https://www.nongnu.org/lwip/2_1_x/group__lwip__nosys.html
// "Feed incoming packets to netif->input(pbuf, netif) function from
// mainloop, not from interrupt context. You can allocate a Packet buffers
// (PBUF) in interrupt context and put them into a queue which is processed
// from mainloop."
// And the description of "Mainloop Mode" option 2:
// https://www.nongnu.org/lwip/2_1_x/pitfalls.html
// "2) Run lwIP in a mainloop. ... lwIP is ONLY called from mainloop
// callstacks here. The ethernet IRQ has to put received telegrams into a
// queue which is polled in the mainloop. Ensure lwIP is NEVER called from
// an interrupt, ...!"
// Based on these comments I am thinking tcp_recv_fn() is called
// from somebody's mainloop(), which could only have been reached from a
// delay like function or the Arduino sketch loop() function has returned.
// What I don't want is for the client sketch to delete the AsyncClient
// object via _error() while it is in the middle of using it. However,
// the client sketch must always test that the connection is still up
// at loop() entry and after the return of any function call, that may
// have done a delay() or yield().
_error(err);
return;
}
if(pb == NULL){
ASYNC_TCP_DEBUG("_recv[%u]: pb == NULL! Closing... %ld\n", errorTracker->getConnectionId(), err);
_close();
return;
}
_rx_last_packet = millis();
errorTracker->setCloseError(ERR_OK);
#if ASYNC_TCP_SSL_ENABLED
if(_pcb_secure){
ASYNC_TCP_DEBUG("_recv[%u]: %d\n", getConnectionId(), pb->tot_len);
int read_bytes = tcp_ssl_read(pcb, pb);
if(read_bytes < 0){
if (read_bytes != SSL_CLOSE_NOTIFY) {
ASYNC_TCP_DEBUG("_recv[%u] err: %d\n", getConnectionId(), read_bytes);
_close();
}
}
return;
}
#endif
while(pb != NULL){
// IF this callback function returns ERR_OK or ERR_ABRT
// then it is assummed we freed the pbufs.
// https://www.nongnu.org/lwip/2_1_x/group__tcp__raw.html#ga8afd0b316a87a5eeff4726dc95006ed0
if(!errorTracker->hasClient()){
while(pb != NULL){
pbuf *b = pb;
pb = b->next;
b->next = NULL;
pbuf_free(b);
}
return;
}
//we should not ack before we assimilate the data
_ack_pcb = true;
pbuf *b = pb;
pb = b->next;
b->next = NULL;
ASYNC_TCP_DEBUG("_recv[%u]: %d%s\n", errorTracker->getConnectionId(), b->len, (b->flags&PBUF_FLAG_PUSH)?", PBUF_FLAG_PUSH":"");
if(_pb_cb){
_pb_cb(_pb_cb_arg, this, b);
} else {
if(_recv_cb){
_recv_pbuf_flags = b->flags;
_recv_cb(_recv_cb_arg, this, b->payload, b->len);
}
if(errorTracker->hasClient()){
if(!_ack_pcb)
_rx_ack_len += b->len;
else
tcp_recved(pcb, b->len);
}
pbuf_free(b);
}
}
return;
}
void AsyncClient::_poll(std::shared_ptr<ACErrorTracker>& errorTracker, tcp_pcb* pcb){
(void)pcb;
errorTracker->setCloseError(ERR_OK);
// Close requested
if(_close_pcb){
_close_pcb = false;
_close();
return;
}
uint32_t now = millis();
// ACK Timeout
if(_pcb_busy && _ack_timeout && (now - _pcb_sent_at) >= _ack_timeout){
_pcb_busy = false;
if(_timeout_cb)
_timeout_cb(_timeout_cb_arg, this, (now - _pcb_sent_at));
return;
}
// RX Timeout
if(_rx_since_timeout && (now - _rx_last_packet) >= (_rx_since_timeout * 1000)){
_close();
return;
}
#if ASYNC_TCP_SSL_ENABLED
// SSL Handshake Timeout
if(_pcb_secure && !_handshake_done && (now - _rx_last_packet) >= 2000){
_close();
return;
}
#endif
// Everything is fine
if(_poll_cb)
_poll_cb(_poll_cb_arg, this);
return;
}
#if LWIP_VERSION_MAJOR == 1
void AsyncClient::_dns_found(struct ip_addr *ipaddr){
#else
void AsyncClient::_dns_found(const ip_addr *ipaddr){
#endif
if(ipaddr){
#if ASYNC_TCP_SSL_ENABLED
connect(IPAddress(ipaddr->addr), _connect_port, _pcb_secure);
#else
connect(IPAddress(ipaddr->addr), _connect_port);
#endif
} else {
if(_error_cb)
_error_cb(_error_cb_arg, this, -55);
if(_discard_cb)
_discard_cb(_discard_cb_arg, this);
}
}
// lwIP Callbacks
#if LWIP_VERSION_MAJOR == 1
void AsyncClient::_s_dns_found(const char *name, ip_addr_t *ipaddr, void *arg){
#else
void AsyncClient::_s_dns_found(const char *name, const ip_addr *ipaddr, void *arg){
#endif
(void)name;
reinterpret_cast<AsyncClient*>(arg)->_dns_found(ipaddr);
}
err_t AsyncClient::_s_poll(void *arg, struct tcp_pcb *tpcb) {
AsyncClient *c = reinterpret_cast<AsyncClient*>(arg);
std::shared_ptr<ACErrorTracker>errorTracker = c->getACErrorTracker();
c->_poll(errorTracker, tpcb);
return errorTracker->getCallbackCloseError();
}
err_t AsyncClient::_s_recv(void *arg, struct tcp_pcb *tpcb, struct pbuf *pb, err_t err) {
AsyncClient *c = reinterpret_cast<AsyncClient*>(arg);
auto errorTracker = c->getACErrorTracker();
c->_recv(errorTracker, tpcb, pb, err);
return errorTracker->getCallbackCloseError();
}
void AsyncClient::_s_error(void *arg, err_t err) {
AsyncClient *c = reinterpret_cast<AsyncClient*>(arg);
auto errorTracker = c->getACErrorTracker();
errorTracker->setCloseError(err);
errorTracker->setErrored(EE_ERROR_CB);
c->_error(err);
}
err_t AsyncClient::_s_sent(void *arg, struct tcp_pcb *tpcb, uint16_t len) {
AsyncClient *c = reinterpret_cast<AsyncClient*>(arg);
auto errorTracker = c->getACErrorTracker();
c->_sent(errorTracker, tpcb, len);
return errorTracker->getCallbackCloseError();
}
err_t AsyncClient::_s_connected(void* arg, void* tpcb, err_t err){
AsyncClient *c = reinterpret_cast<AsyncClient*>(arg);
auto errorTracker = c->getACErrorTracker();
c->_connected(errorTracker, tpcb, err);
return errorTracker->getCallbackCloseError();
}
#if ASYNC_TCP_SSL_ENABLED
void AsyncClient::_s_data(void *arg, struct tcp_pcb *tcp, uint8_t * data, size_t len){
AsyncClient *c = reinterpret_cast<AsyncClient*>(arg);
if(c->_recv_cb)
c->_recv_cb(c->_recv_cb_arg, c, data, len);
}
void AsyncClient::_s_handshake(void *arg, struct tcp_pcb *tcp, SSL *ssl){
AsyncClient *c = reinterpret_cast<AsyncClient*>(arg);
c->_handshake_done = true;
if(c->_connect_cb)
c->_connect_cb(c->_connect_cb_arg, c);
}
void AsyncClient::_s_ssl_error(void *arg, struct tcp_pcb *tcp, int8_t err){
reinterpret_cast<AsyncClient*>(arg)->_ssl_error(err);
}
#endif
// Operators
AsyncClient & AsyncClient::operator+=(const AsyncClient &other) {
if(next == NULL){
next = (AsyncClient*)(&other);
next->prev = this;
} else {
AsyncClient *c = next;
while(c->next != NULL) c = c->next;
c->next =(AsyncClient*)(&other);
c->next->prev = c;
}
return *this;
}
void AsyncClient::setRxTimeout(uint32_t timeout){
_rx_since_timeout = timeout;
}
uint32_t AsyncClient::getRxTimeout(){
return _rx_since_timeout;
}
uint32_t AsyncClient::getAckTimeout(){
return _ack_timeout;
}
void AsyncClient::setAckTimeout(uint32_t timeout){
_ack_timeout = timeout;
}
void AsyncClient::setNoDelay(bool nodelay){
if(!_pcb)
return;
if(nodelay)
tcp_nagle_disable(_pcb);
else
tcp_nagle_enable(_pcb);
}
bool AsyncClient::getNoDelay(){
if(!_pcb)
return false;
return tcp_nagle_disabled(_pcb);
}
uint16_t AsyncClient::getMss(){
if(_pcb)
return tcp_mss(_pcb);
return 0;
}
uint32_t AsyncClient::getRemoteAddress() {
if(!_pcb)
return 0;
return _pcb->remote_ip.addr;
}
uint16_t AsyncClient::getRemotePort() {
if(!_pcb)
return 0;
return _pcb->remote_port;
}
uint32_t AsyncClient::getLocalAddress() {
if(!_pcb)
return 0;
return _pcb->local_ip.addr;
}
uint16_t AsyncClient::getLocalPort() {
if(!_pcb)
return 0;
return _pcb->local_port;
}
IPAddress AsyncClient::remoteIP() {
return IPAddress(getRemoteAddress());
}
uint16_t AsyncClient::remotePort() {
return getRemotePort();
}
IPAddress AsyncClient::localIP() {
return IPAddress(getLocalAddress());
}
uint16_t AsyncClient::localPort() {
return getLocalPort();
}
#if ASYNC_TCP_SSL_ENABLED
SSL * AsyncClient::getSSL(){
if(_pcb && _pcb_secure){
return tcp_ssl_get_ssl(_pcb);
}
return NULL;
}
#endif
uint8_t AsyncClient::state() {
if(!_pcb)
return 0;
return _pcb->state;
}
bool AsyncClient::connected(){
if (!_pcb)
return false;
#if ASYNC_TCP_SSL_ENABLED
return _pcb->state == 4 && _handshake_done;
#else
return _pcb->state == 4;
#endif
}
bool AsyncClient::connecting(){
if (!_pcb)
return false;
return _pcb->state > 0 && _pcb->state < 4;
}
bool AsyncClient::disconnecting(){
if (!_pcb)
return false;
return _pcb->state > 4 && _pcb->state < 10;
}
bool AsyncClient::disconnected(){
if (!_pcb)
return true;
return _pcb->state == 0 || _pcb->state == 10;
}
bool AsyncClient::freeable(){
if (!_pcb)
return true;
return _pcb->state == 0 || _pcb->state > 4;
}
bool AsyncClient::canSend(){
return !_pcb_busy && (space() > 0);
}
// Callback Setters
void AsyncClient::onConnect(AcConnectHandler cb, void* arg){
_connect_cb = cb;
_connect_cb_arg = arg;
}
void AsyncClient::onDisconnect(AcConnectHandler cb, void* arg){
_discard_cb = cb;
_discard_cb_arg = arg;
}
void AsyncClient::onAck(AcAckHandler cb, void* arg){
_sent_cb = cb;
_sent_cb_arg = arg;
}
void AsyncClient::onError(AcErrorHandler cb, void* arg){
_error_cb = cb;
_error_cb_arg = arg;
}
void AsyncClient::onData(AcDataHandler cb, void* arg){
_recv_cb = cb;
_recv_cb_arg = arg;
}
void AsyncClient::onPacket(AcPacketHandler cb, void* arg){
_pb_cb = cb;
_pb_cb_arg = arg;
}
void AsyncClient::onTimeout(AcTimeoutHandler cb, void* arg){
_timeout_cb = cb;
_timeout_cb_arg = arg;
}
void AsyncClient::onPoll(AcConnectHandler cb, void* arg){
_poll_cb = cb;
_poll_cb_arg = arg;
}
size_t AsyncClient::space(){
#if ASYNC_TCP_SSL_ENABLED
if((_pcb != NULL) && (_pcb->state == 4) && _handshake_done){
uint16_t s = tcp_sndbuf(_pcb);
if(_pcb_secure){
#ifdef AXTLS_2_0_0_SNDBUF
return tcp_ssl_sndbuf(_pcb);
#else
if(s >= 128) //safe approach
return s - 128;
return 0;
#endif
}
return s;
}
#else // ASYNC_TCP_SSL_ENABLED
if((_pcb != NULL) && (_pcb->state == 4)){
return tcp_sndbuf(_pcb);
}
#endif // ASYNC_TCP_SSL_ENABLED
return 0;
}
void AsyncClient::ackPacket(struct pbuf * pb){
if(!pb){
return;
}
tcp_recved(_pcb, pb->len);
pbuf_free(pb);
}