最近想自己搭建一个webscoket协议的服务器，打算用libwebsockts这个库。
下载代码编译。
编写一个shell脚本
#!/bin/sh
# wget http://git.warmcat.com/cgi-bin/cgit/libwebsockets/snapshot/libwebsockets-1.4-chrome43-firefox-36.tar.gz
# tar xvzf libwebsockets-1.4-chrome43-firefox-36.tar.gz
#cd libwebsockets-1.4-chrome43-firefox-36
# build
git clone https://github.com/warmcat/libwebsockets.git
cd libwebsockets
documentRoot=`pwd`
mkdir build
cmake ..
make
执行shell脚本就下载编译成功了。
运行一个例子
其实在库里面有一些实例的.
cd build这样就运行自带的服务器。运行结果.
#!/bin/sh
documentRoot=`pwd`
libdir=libwebsockets
cd $libdir/build/bin
./libwebsockets-test-server --resource_path=$documentRoot/test-server
浏览器输入127.0.0.1:7681结果:
这样就是完整的结果了。
搭建自己的websocket server
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <libwebsockets.h>
#define KGRN "\033[0;32;32m"
#define KCYN "\033[0;36m"
#define KRED "\033[0;32;31m"
#define KYEL "\033[1;33m"
#define KMAG "\033[0;35m"
#define KBLU "\033[0;32;34m"
#define KCYN_L "\033[1;36m"
#define RESET "\033[0m"
static int destroy_flag = 0;
static void INT_HANDLER(int signo) {
destroy_flag = 0;
}
/* *
* websocket_write_back: write the string data to the destination wsi.
*/
int websocket_write_back(struct lws *wsi_in, char *str, int str_size_in)
{
if (str == NULL || wsi_in == NULL)
return -1;
int n;
int len;
unsigned char *out = NULL;
if (str_size_in < 1)
len = strlen(str);
else
len = str_size_in;
out = (unsigned char *)malloc(sizeof(unsigned char)*(LWS_SEND_BUFFER_PRE_PADDING + len + LWS_SEND_BUFFER_POST_PADDING));
//* setup the buffer*/
memcpy (out + LWS_SEND_BUFFER_PRE_PADDING, str, len );
//* write out*/
n = lws_write(wsi_in, out + LWS_SEND_BUFFER_PRE_PADDING, len, LWS_WRITE_TEXT);
printf(KBLU"[websocket_write_back] %s\n"RESET, str);
//* free the buffer*/
free(out);
return n;
}
static int ws_service_callback(
struct lws *wsi,
enum lws_callback_reasons reason, void *user,
void *in, size_t len)
{
switch (reason) {
case LWS_CALLBACK_ESTABLISHED:
printf(KYEL"[Main Service] Connection established\n"RESET);
break;
//* If receive a data from client*/
case LWS_CALLBACK_RECEIVE:
printf(KCYN_L"[Main Service] Server recvived:%s\n"RESET,(char *)in);
//* echo back to client*/
websocket_write_back(wsi ,(char *)in, -1);
break;
case LWS_CALLBACK_CLOSED:
printf(KYEL"[Main Service] Client close.\n"RESET);
break;
default:
break;
}
return 0;
}
struct per_session_data {
int fd;
};
int main(void) {
// server url will usd port 5000
int port = 5000;
const char *interface = NULL;
struct lws_context_creation_info info;
struct lws_protocols protocol;
struct lws_context *context;
// Not using ssl
const char *cert_path = NULL;
const char *key_path = NULL;
// no special options
int opts = 0;
//* register the signal SIGINT handler */
struct sigaction act;
act.sa_handler = INT_HANDLER;
act.sa_flags = 0;
sigemptyset(&act.sa_mask);
sigaction( SIGINT, &act, 0);
//* setup websocket protocol */
protocol.name = "my-echo-protocol";
protocol.callback = ws_service_callback;
protocol.per_session_data_size=sizeof(struct per_session_data);
protocol.rx_buffer_size = 0;
//* setup websocket context info*/
memset(&info, 0, sizeof info);
info.port = port;
info.iface = interface;
info.protocols = &protocol;
info.extensions = lws_get_internal_extensions();
info.ssl_cert_filepath = cert_path;
info.ssl_private_key_filepath = key_path;
info.gid = -1;
info.uid = -1;
info.options = opts;
//* create libwebsocket context. */
context = lws_create_context(&info);
if (context == NULL) {
printf(KRED"[Main] Websocket context create error.\n"RESET);
return -1;
}
printf(KGRN"[Main] Websocket context create success.\n"RESET);
//* websocket service */
while ( !destroy_flag ) {
lws_service(context, 50);
}
usleep(10);
lws_context_destroy(context);
return 0;
}
执行脚本:
#!/bin/sh
libdir=libwebsockets
g++ test_ws_server.cpp -o ws_server -I$libdir/lib -I$libdir/build -L$libdir/build/lib -lwebsockets
编写自己的websocket client
#include <stdio.h>编写脚本:
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <pthread.h>
#include <libwebsockets.h>
#define KGRN "\033[0;32;32m"
#define KCYN "\033[0;36m"
#define KRED "\033[0;32;31m"
#define KYEL "\033[1;33m"
#define KBLU "\033[0;32;34m"
#define KCYN_L "\033[1;36m"
#define KBRN "\033[0;33m"
#define RESET "\033[0m"
static int destroy_flag = 0;
static int connection_flag = 0;
static int writeable_flag = 0;
static void INT_HANDLER(int signo) {
destroy_flag = 0;
}
struct session_data {
int fd;
};
struct pthread_routine_tool {
struct lws_context *context;
struct lws *wsi;
};
static int websocket_write_back(struct lws *wsi_in, char *str, int str_size_in)
{
if (str == NULL || wsi_in == NULL)
return -1;
int n;
int len;
unsigned char *out = NULL;
if (str_size_in < 1)
len = strlen(str);
else
len = str_size_in;
out = (unsigned char *)malloc(sizeof(unsigned char)*(LWS_SEND_BUFFER_PRE_PADDING + len + LWS_SEND_BUFFER_POST_PADDING));
//* setup the buffer*/
memcpy (out + LWS_SEND_BUFFER_PRE_PADDING, str, len );
//* write out*/
n = lws_write(wsi_in, out + LWS_SEND_BUFFER_PRE_PADDING, len, LWS_WRITE_TEXT);
printf(KBLU"[websocket_write_back] %s\n"RESET, str);
//* free the buffer*/
free(out);
return n;
}
static int ws_service_callback(
struct lws *wsi,
enum lws_callback_reasons reason, void *user,
void *in, size_t len)
{
switch (reason) {
case LWS_CALLBACK_CLIENT_ESTABLISHED:
printf(KYEL"[Main Service] Connect with server success.\n"RESET);
connection_flag = 1;
break;
case LWS_CALLBACK_CLIENT_CONNECTION_ERROR:
printf(KRED"[Main Service] Connect with server error.\n"RESET);
destroy_flag = 1;
connection_flag = 0;
break;
case LWS_CALLBACK_CLOSED:
printf(KYEL"[Main Service] LWS_CALLBACK_CLOSED\n"RESET);
destroy_flag = 1;
connection_flag = 0;
break;
case LWS_CALLBACK_CLIENT_RECEIVE:
printf(KCYN_L"[Main Service] Client recvived:%s\n"RESET, (char *)in);
if (writeable_flag)
destroy_flag = 1;
break;
case LWS_CALLBACK_CLIENT_WRITEABLE :
printf(KYEL"[Main Service] On writeable is called. send byebye message\n"RESET);
websocket_write_back(wsi, "Byebye! See you later", -1);
writeable_flag = 1;
break;
default:
break;
}
return 0;
}
static void *pthread_routine(void *tool_in)
{
struct pthread_routine_tool *tool = (struct pthread_routine_tool*)tool_in;
printf(KBRN"[pthread_routine] Good day. This is pthread_routine.\n"RESET);
//* waiting for connection with server done.*/
while(!connection_flag)
usleep(1000*20);
//*Send greeting to server*/
printf(KBRN"[pthread_routine] Server is ready. send a greeting message to server.\n"RESET);
websocket_write_back(tool->wsi, "Good day", -1);
printf(KBRN"[pthread_routine] sleep 2 seconds then call onWritable\n"RESET);
sleep(1);
printf(KBRN"------------------------------------------------------\n"RESET);
sleep(1);
//printf(KBRN"[pthread_routine] sleep 2 seconds then call onWritable\n"RESET);
//*involked wriable*/
printf(KBRN"[pthread_routine] call on writable.\n"RESET);
lws_callback_on_writable(tool->wsi);
}
int main(void)
{
//* register the signal SIGINT handler */
struct sigaction act;
act.sa_handler = INT_HANDLER;
act.sa_flags = 0;
sigemptyset(&act.sa_mask);
sigaction( SIGINT, &act, 0);
struct lws_context *context = NULL;
struct lws_context_creation_info info;
struct lws *wsi = NULL;
struct lws_protocols protocol;
memset(&info, 0, sizeof info);
info.port = CONTEXT_PORT_NO_LISTEN;
info.iface = NULL;
info.protocols = &protocol;
info.ssl_cert_filepath = NULL;
info.ssl_private_key_filepath = NULL;
info.extensions = lws_get_internal_extensions();
info.gid = -1;
info.uid = -1;
info.options = 0;
protocol.name = "my-echo-protocol";
protocol.callback = &ws_service_callback;
protocol.per_session_data_size = sizeof(struct session_data);
protocol.rx_buffer_size = 0;
protocol.id = 0;
protocol.user = NULL;
context = lws_create_context(&info);
printf(KRED"[Main] context created.\n"RESET);
if (context == NULL) {
printf(KRED"[Main] context is NULL.\n"RESET);
return -1;
}wsi = lws_client_connect(context, "localhost", 5000, 0,
"/", "localhost:5000", NULL,
protocol.name, -1);
if (wsi == NULL) {
printf(KRED"[Main] wsi create error.\n"RESET);
return -1;
}
printf(KGRN"[Main] wsi create success.\n"RESET);
struct pthread_routine_tool tool;
tool.wsi = wsi;
tool.context = context;
pthread_t pid;
pthread_create(&pid, NULL, pthread_routine, &tool);
pthread_detach(pid);
while(!destroy_flag)
{
lws_service(context, 50);
}
lws_context_destroy(context);
return 0;
}
#!/bin/sh
libdir=libwebsockets
g++ test_ws_client.cpp -o ws_client -I$libdir/lib -I$libdir/build -L$libdir/build/lib -lwebsockets -lpthread
运行结果
红线部分是交互的结果.这样就是完整的一套逻辑了.