esp-idf/components/tcp_transport/transport_tcp.c
David Cermak ce519ee783 tcp_transport: Extend transport error storage for socket error
Everytime we report error and log errno, we also capture the actual
errno to an internal storage so that user application can retrieve
its value.
2020-11-12 12:46:22 +00:00

266 lines
8.4 KiB
C

// Copyright 2015-2018 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <stdlib.h>
#include <string.h>
#include "lwip/sockets.h"
#include "lwip/dns.h"
#include "lwip/netdb.h"
#include "esp_log.h"
#include "esp_system.h"
#include "esp_err.h"
#include "esp_transport_utils.h"
#include "esp_transport.h"
#include "esp_transport_internal.h"
static const char *TAG = "TRANS_TCP";
typedef struct {
int sock;
} transport_tcp_t;
static int resolve_dns(const char *host, struct sockaddr_in *ip)
{
const struct addrinfo hints = {
.ai_family = AF_INET,
.ai_socktype = SOCK_STREAM,
};
struct addrinfo *res;
int err = getaddrinfo(host, NULL, &hints, &res);
if(err != 0 || res == NULL) {
ESP_LOGE(TAG, "DNS lookup failed err=%d res=%p", err, res);
return ESP_FAIL;
}
ip->sin_family = AF_INET;
memcpy(&ip->sin_addr, &((struct sockaddr_in *)(res->ai_addr))->sin_addr, sizeof(ip->sin_addr));
freeaddrinfo(res);
return ESP_OK;
}
static int tcp_connect(esp_transport_handle_t t, const char *host, int port, int timeout_ms)
{
struct sockaddr_in remote_ip;
struct timeval tv = { 0 };
transport_tcp_t *tcp = esp_transport_get_context_data(t);
bzero(&remote_ip, sizeof(struct sockaddr_in));
//if stream_host is not ip address, resolve it AF_INET,servername,&serveraddr.sin_addr
if (inet_pton(AF_INET, host, &remote_ip.sin_addr) != 1) {
if (resolve_dns(host, &remote_ip) < 0) {
return -1;
}
}
tcp->sock = socket(PF_INET, SOCK_STREAM, 0);
if (tcp->sock < 0) {
ESP_LOGE(TAG, "Error create socket");
return -1;
}
remote_ip.sin_family = AF_INET;
remote_ip.sin_port = htons(port);
esp_transport_utils_ms_to_timeval(timeout_ms, &tv); // if timeout=-1, tv is unchanged, 0, i.e. waits forever
setsockopt(tcp->sock, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
setsockopt(tcp->sock, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv));
// Set socket to non-blocking
int flags;
if ((flags = fcntl(tcp->sock, F_GETFL, NULL)) < 0) {
ESP_LOGE(TAG, "[sock=%d] get file flags error: %s", tcp->sock, strerror(errno));
goto error;
}
if (fcntl(tcp->sock, F_SETFL, flags |= O_NONBLOCK) < 0) {
ESP_LOGE(TAG, "[sock=%d] set nonblocking error: %s", tcp->sock, strerror(errno));
goto error;
}
ESP_LOGD(TAG, "[sock=%d] Connecting to server. IP: %s, Port: %d",
tcp->sock, ipaddr_ntoa((const ip_addr_t*)&remote_ip.sin_addr.s_addr), port);
if (connect(tcp->sock, (struct sockaddr *)(&remote_ip), sizeof(struct sockaddr)) < 0) {
if (errno == EINPROGRESS) {
fd_set fdset;
esp_transport_utils_ms_to_timeval(timeout_ms, &tv);
FD_ZERO(&fdset);
FD_SET(tcp->sock, &fdset);
int res = select(tcp->sock+1, NULL, &fdset, NULL, &tv);
if (res < 0) {
ESP_LOGE(TAG, "[sock=%d] select() error: %s", tcp->sock, strerror(errno));
esp_transport_capture_errno(t, errno);
goto error;
}
else if (res == 0) {
ESP_LOGE(TAG, "[sock=%d] select() timeout", tcp->sock);
esp_transport_capture_errno(t, EINPROGRESS); // errno=EINPROGRESS indicates connection timeout
goto error;
} else {
int sockerr;
socklen_t len = (socklen_t)sizeof(int);
if (getsockopt(tcp->sock, SOL_SOCKET, SO_ERROR, (void*)(&sockerr), &len) < 0) {
ESP_LOGE(TAG, "[sock=%d] getsockopt() error: %s", tcp->sock, strerror(errno));
goto error;
}
else if (sockerr) {
esp_transport_capture_errno(t, sockerr);
ESP_LOGE(TAG, "[sock=%d] delayed connect error: %s", tcp->sock, strerror(sockerr));
goto error;
}
}
} else {
ESP_LOGE(TAG, "[sock=%d] connect() error: %s", tcp->sock, strerror(errno));
goto error;
}
}
// Reset socket to blocking
if ((flags = fcntl(tcp->sock, F_GETFL, NULL)) < 0) {
ESP_LOGE(TAG, "[sock=%d] get file flags error: %s", tcp->sock, strerror(errno));
goto error;
}
if (fcntl(tcp->sock, F_SETFL, flags & ~O_NONBLOCK) < 0) {
ESP_LOGE(TAG, "[sock=%d] reset blocking error: %s", tcp->sock, strerror(errno));
goto error;
}
return tcp->sock;
error:
close(tcp->sock);
tcp->sock = -1;
return -1;
}
static int tcp_write(esp_transport_handle_t t, const char *buffer, int len, int timeout_ms)
{
int poll;
transport_tcp_t *tcp = esp_transport_get_context_data(t);
if ((poll = esp_transport_poll_write(t, timeout_ms)) <= 0) {
return poll;
}
return write(tcp->sock, buffer, len);
}
static int tcp_read(esp_transport_handle_t t, char *buffer, int len, int timeout_ms)
{
transport_tcp_t *tcp = esp_transport_get_context_data(t);
int poll = -1;
if ((poll = esp_transport_poll_read(t, timeout_ms)) <= 0) {
return poll;
}
int read_len = read(tcp->sock, buffer, len);
if (read_len == 0) {
return -1;
}
return read_len;
}
static int tcp_poll_read(esp_transport_handle_t t, int timeout_ms)
{
transport_tcp_t *tcp = esp_transport_get_context_data(t);
int ret = -1;
struct timeval timeout;
fd_set readset;
fd_set errset;
FD_ZERO(&readset);
FD_ZERO(&errset);
FD_SET(tcp->sock, &readset);
FD_SET(tcp->sock, &errset);
ret = select(tcp->sock + 1, &readset, NULL, &errset, esp_transport_utils_ms_to_timeval(timeout_ms, &timeout));
if (ret > 0 && FD_ISSET(tcp->sock, &errset)) {
int sock_errno = 0;
uint32_t optlen = sizeof(sock_errno);
getsockopt(tcp->sock, SOL_SOCKET, SO_ERROR, &sock_errno, &optlen);
esp_transport_capture_errno(t, sock_errno);
ESP_LOGE(TAG, "tcp_poll_read select error %d, errno = %s, fd = %d", sock_errno, strerror(sock_errno), tcp->sock);
ret = -1;
}
return ret;
}
static int tcp_poll_write(esp_transport_handle_t t, int timeout_ms)
{
transport_tcp_t *tcp = esp_transport_get_context_data(t);
int ret = -1;
struct timeval timeout;
fd_set writeset;
fd_set errset;
FD_ZERO(&writeset);
FD_ZERO(&errset);
FD_SET(tcp->sock, &writeset);
FD_SET(tcp->sock, &errset);
ret = select(tcp->sock + 1, NULL, &writeset, &errset, esp_transport_utils_ms_to_timeval(timeout_ms, &timeout));
if (ret > 0 && FD_ISSET(tcp->sock, &errset)) {
int sock_errno = 0;
uint32_t optlen = sizeof(sock_errno);
getsockopt(tcp->sock, SOL_SOCKET, SO_ERROR, &sock_errno, &optlen);
esp_transport_capture_errno(t, sock_errno);
ESP_LOGE(TAG, "tcp_poll_write select error %d, errno = %s, fd = %d", sock_errno, strerror(sock_errno), tcp->sock);
ret = -1;
}
return ret;
}
static int tcp_close(esp_transport_handle_t t)
{
transport_tcp_t *tcp = esp_transport_get_context_data(t);
int ret = -1;
if (tcp->sock >= 0) {
ret = close(tcp->sock);
tcp->sock = -1;
}
return ret;
}
static esp_err_t tcp_destroy(esp_transport_handle_t t)
{
transport_tcp_t *tcp = esp_transport_get_context_data(t);
esp_transport_close(t);
free(tcp);
return 0;
}
static int tcp_get_socket(esp_transport_handle_t t)
{
if (t) {
transport_tcp_t *tcp = t->data;
if (tcp) {
return tcp->sock;
}
}
return -1;
}
esp_transport_handle_t esp_transport_tcp_init(void)
{
esp_transport_handle_t t = esp_transport_init();
transport_tcp_t *tcp = calloc(1, sizeof(transport_tcp_t));
ESP_TRANSPORT_MEM_CHECK(TAG, tcp, return NULL);
tcp->sock = -1;
esp_transport_set_func(t, tcp_connect, tcp_read, tcp_write, tcp_close, tcp_poll_read, tcp_poll_write, tcp_destroy);
esp_transport_set_context_data(t, tcp);
t->_get_socket = tcp_get_socket;
return t;
}