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问题：如何设计与客户端对应的服务端?
TCP 通信框架设计
服务端
-
负责监听连贯状态
- Connect : 产生通信客户端（TcpClient）, 并给出事件告诉
- Close : 给出事件告诉，并销毁客户端
- 负责监听数据通信状态，并给出事件告诉
服务端事件设计
- EVT_CONN: 客户端连贯服务端时触发，并创立 TcpClient 用于通信
- EVT_DATA: 客户端数据达到服务端时触发，应用 TcpClient 读取数据
- EVT_CLOSE: 客户端断开服务时触发，相干 TcpClient 将销毁
问题：服务端如何晓得什么时候进行事件回调告诉？
服务端通过 select 机制触发事件回调!
服务端接口设计
typedef void TcpServer;
typedef void (*Listener)(TcpClient*, int);
enum {
EVT_CONN,
EVT_DATA,
EVT_CLOSE
};
TcpServer *TcpServer_New();
int TcpServer_Start(TcpServer *server, int port, int max);
void TcpServer_Stop(TcpServer *server);
void TcpServer_SetListener(TcpServer *server, Listener listener);
int TcpServer_IsValid(TcpServer *server);
void TcpServer_DoWork(TcpServer *server);
void TcpServer_Del(TcpServer *server);服务端要害代码实现 – 初始化
typedef struct tcp_server {
int fd;
int valid;
Listener cb;
TcpClient *client[FD_SIZE];
}Server;
TcpServer *TcpServer_New()
{Server *ret = malloc(sizeof(Server));
if (ret) {
int i = 0;
ret->fd = -1;
ret->valid = 0;
ret->cb = NULL;
}
return ret;
}服务端要害代码实现 – 事件监听
FD_ZERO(&reads);
FD_SET(s->fd, &reads);
max = s->fd;
while (s->valid) {
rset = reads;
timeout.tv_sec = 0;
timeout.tv_usec = 5000;
num = select(max+1, &rset, 0, 0, &timeout);
if (num > 0) {max = SelectHandler(s, &rset, &reads, num, mac);
}
}服务器要害代码实现 – 连贯事件 & 数据事件
if (index == s->fd) { // 连贯事件
struct sockaddr_in caddr = {0};
socklen_t asize = sizeof(caddr);
index = accept(s->fd, (struct sockaddr*)&addr, &asize);
if (index > -1) {FD_SET(index, reads);
ret = (index > max) ? index : max;
s->client[index] = TcpClient_From(index);
event = EVT_CONN;
}
} else { // 数据事件
event = EVT_DATA;
}服务器要害代码实现 – 断开事件 & 事件告诉
if (s->cb) {if (TcpClient_IsValid(s->client[index])) {s->cb(s->client[index], event); // EVT_CONN & EVT_DATA 事件告诉
} else {if (s->client[index]) {s->cb(s->client[index], EVT_CLOSE); // 断连事件告诉
TcpClient_Del(s->client[index]);
s->client[index] = NULL;
FD_CLR(index, reads);
}
}
}编程试验
tcp_server.h
#ifndef TCP_SERVER_H
#define TCP_SERVER_H
#include "tcp_client.h"
typedef void TcpServer;
typedef void (*Listener)(TcpClient*, int);
enum {
EVT_CONN,
EVT_DATA,
EVT_CLOSE
};
TcpServer *TcpServer_New();
int TcpServer_Start(TcpServer *server, int port, int max);
void TcpServer_Stop(TcpServer *server);
void TcpServer_SetListener(TcpServer *server, Listener listener);
int TcpServer_IsValid(TcpServer *server);
void TcpServer_DoWork(TcpServer *server);
void TcpServer_Del(TcpServer *server);
#endiftcp_server.c
#include "tcp_server.h"
#include "tcp_client.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/select.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <malloc.h>
#define FD_SIZE 1024
typedef struct tcp_server {
int fd;
int valid;
Listener cb;
TcpClient *client[FD_SIZE];
}Server;
TcpServer *TcpServer_New()
{Server *ret = malloc(sizeof(Server));
if (ret) {
int i = 0;
ret->fd = -1;
ret->valid = 0;
ret->cb = NULL;
for (i=0; i<FD_SIZE; ++i) {ret->client[i] = NULL;
}
}
return ret;
}
int TcpServer_Start(TcpServer *server, int port, int max)
{Server *s = (Server*)server;
if (s && !s->valid) {struct sockaddr_in saddr = {0};
s->fd = socket(PF_INET, SOCK_STREAM, 0);
s->valid = (s->fd != -1);
saddr.sin_family = AF_INET;
saddr.sin_addr.s_addr = htonl(INADDR_ANY);
saddr.sin_port = htons(port);
s->valid = s->valid && (bind(s->fd, (struct sockaddr*)&saddr, sizeof(saddr)) != -1);
s->valid = s->valid && (listen(s->fd, max) != -1);
}
return s->valid;
}
void TcpServer_Stop(TcpServer *server)
{Server *s = (Server*)server;
if (s) {
int i =0;
s->valid = 0;
close(s->fd);
for (i=0; i<FD_SIZE; ++i) {TcpClient_Del(s->client[i]);
s->client[i] = NULL;
}
}
}
void TcpServer_SetListener(TcpServer *server, Listener listener)
{Server *s = (Server*)server;
if (s) {s->cb = listener;}
}
int TcpServer_IsValid(TcpServer *server)
{return server ? ((Server*)server)->valid : 0;
}
static int SelectHandler(Server *s, fd_set *rset, fd_set *reads, int num, int max)
{
int ret = max;
int i =0;
for (i=0; i<=max; ++i) {if (FD_ISSET(i, rset)) {
int index = i;
int event = -1;
if (index == s->fd) {struct sockaddr_in caddr = {0};
socklen_t asize = sizeof(struct sockaddr_in);
index = accept(s->fd, (struct sockaddr*)&caddr, &asize);
if (index > -1) {FD_SET(index, reads);
ret = (index > max) ? index : max;
s->client[index] = TcpClient_From(index);
event = EVT_CONN;
}
}
else {event = EVT_DATA;}
if (s->cb) {if (TcpClient_IsValid(s->client[index])) {s->cb(s->client[index], event);
} else {if (s->client[index]) {s->cb(s->client[index], EVT_CLOSE);
}
TcpClient_Del(s->client[index]);
s->client[index] = NULL;
FD_CLR(index, reads);
}
}
}
}
return ret;
}
void TcpServer_DoWork(TcpServer *server)
{Server *s = (Server*)server;
if (s && s->valid) {
int max = 0;
int num = 0;
fd_set reads = {0};
fd_set rset = {0};
struct timeval timeout = {0};
FD_ZERO(&reads);
FD_SET(s->fd, &reads);
max = s->fd;
while (s->valid) {
rset = reads;
timeout.tv_sec = 0;
timeout.tv_usec = 10000;
num = select(max + 1, &rset, 0, 0, &timeout);
if (num > 0) {max = SelectHandler(s, &rset, &reads, num, max);
}
}
}
}
void TcpServer_Del(TcpServer *server)
{TcpServer_Stop(server);
free(server);
}测试：server.c
#include <stdio.h>
#include <string.h>
#include <malloc.h>
#include "tcp_server.h"
void EventListener(TcpClient *client, int evt)
{if (evt == EVT_CONN) {printf("Connect: %p\n", client);
} else if (evt == EVT_DATA) {Message *m = TcpClient_RecvMsg(client);
if (m) {char *s = TcpClient_GetDate(client);
if (m->index == 0) {s = malloc(m->total + 1);
TcpClient_SetData(client, s);
}
strcpy(s+m->index, m->payload);
if ((m->index + 1) == m->total) {printf("Data: %s\n", s);
free(s);
}
free(m);
}
}
else if (evt == EVT_CLOSE) {printf("close: %p\n", client);
}
}
int main()
{TcpServer *server = TcpServer_New();
if (server) {int r = TcpServer_Start(server, 8888, 20);
if (r) {TcpServer_SetListener(server, EventListener);
TcpServer_DoWork(server);
}
}
return 0;
}输入：
Connect: 0x5602eb035690
Data: D.T.Software
close: 0x5602eb035690正文完