Windows 和 Linux下使用socket下载网页页面内容（可设置接收/发送超时）的代码

主要难点在于设置recv()与send()的超时时间，具体要注意的事项，请看代码注释部分，下面是代码：

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#include <stdio.h>

#include <sys/types.h>

#include <stdlib.h>

#include <string.h>

#include <errno.h>

#include <string.h>

#ifdef _WIN32 ///包含win socket相关头文件

#include <winsock.h>

#pragma comment(lib,"ws2_32.lib")

#else ///包含linux socket相关头文件

#include <unistd.h>

#include <strings.h>

#include <netinet/in.h>

#include <sys/socket.h>

#include <arpa/inet.h>

#include <netdb.h>

#include <fcntl.h>

#include <stdint.h>

#endif

#ifdef _WIN32

#ifdef __cplusplus

extern "C"{

#endif

int strcasecmp(const char *s1, const char *s2)

{

while ((*s1 != '\0')

&& (tolower(*(unsigned char *) s1) ==

tolower(*(unsigned char *) s2)))

{

s1++;

s2++;

}

return tolower(*(unsigned char *) s1) - tolower(*(unsigned char *) s2);

}

int strncasecmp(const char *s1, const char *s2, unsigned int n)

{

if (n == 0)

return 0;

while ((n-- != 0)

&& (tolower(*(unsigned char *) s1) ==

tolower(*(unsigned char *) s2))) {

if (n == 0 || *s1 == '\0' || *s2 == '\0')

return 0;

s1++;

s2++;

}

return tolower(*(unsigned char *) s1) - tolower(*(unsigned char *) s2);

}

#ifdef __cplusplus

}

#endif

#endif

/**********************************

*功能:Base64编码

*参数:

src_data:待编码的字符串

coded_data:编码后的字符串

*返回值:-1,失败;0,成功

***********************************/

int base64encode(const char * src_data/*in,待编码的字符串*/,char * coded_data/*out,编码后的字符串*/)

{

const char EncodeTable[]="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

int src_data_len = strlen(src_data);

int i;

int lineLength=0;

int mod=src_data_len % 3;

unsigned char tmp[4]={0};

char buff[5]={0};

for(i=0;i<(int)(src_data_len / 3);i++)

{

tmp[1] = *src_data++;

tmp[2] = *src_data++;

tmp[3] = *src_data++;

sprintf(buff,"%c%c%c%c", EncodeTable[tmp[1] >> 2],EncodeTable[((tmp[1] << 4) | (tmp[2] >> 4)) & 0x3F],EncodeTable[((tmp[2] << 2) | (tmp[3] >> 6)) & 0x3F],EncodeTable[tmp[3] & 0x3F]);

strcat(coded_data,buff);

if(lineLength+=4,lineLength==76)

{

strcat(coded_data,"\r\n");

lineLength=0;

}

}

if(mod==1)

{

tmp[1] = *src_data++;

sprintf(buff,"%c%c==",EncodeTable[(tmp[1] & 0xFC) >> 2],EncodeTable[((tmp[1] & 0x03) << 4)]);

strcat(coded_data,buff);

}

else if(mod==2)

{

tmp[1] = *src_data++;

tmp[2] = *src_data++;

sprintf(buff,"%c%c%c=",EncodeTable[(tmp[1] & 0xFC) >> 2],EncodeTable[((tmp[1] & 0x03) << 4) | ((tmp[2] & 0xF0) >> 4)],EncodeTable[((tmp[2] & 0x0F) << 2)]);

strcat(coded_data,buff);

}

return 0;

}

//格式化http头,返回值:-1失败,-2用户名或密码无效;>=0 成功

int format_http_header(const char * webserverip,

unsigned short httpport/*web server 端口*/,

const char * url/*页面相对url,下载的页面为:http://ip/url"*/,

const char * username/*网站认证用户*/,

const char * password/*认证密码*/,

const char * ext_param/*访问网页附加参数*/,

int net_timeout/*超时时间,秒*/,

char header[512]/*out*/)

{

int len =0;

char buf_auth[100]={0},auth[100]={0};

sprintf(buf_auth,"%s:%s",username,password);

base64encode(buf_auth,auth);

if(ext_param)

{

len = strlen(ext_param);

}

if(len)

{

//GET

return sprintf(header,

"GET /%s?%s HTTP/1.1\r\n"

"Host:%s:%u\r\n"

"Content-Type: application/x-www-form-urlencoded\r\n"

"Keep-Alive: Keep-Alive: timeout=%d\r\n"

"Connection: keep-alive\r\n"

"Accept:text/html\r\n"

"Authorization: Basic %s\r\n"

"\r\n"

,url,ext_param,webserverip,httpport,net_timeout,auth

);

}

//GET

return sprintf(header,

"GET /%s HTTP/1.1\r\n"

"Host:%s:%u\r\n"

"Content-Type: application/x-www-form-urlencoded\r\n"

"Keep-Alive: timeout=%d\r\n"

"Connection: keep-alive\r\n"

"Accept:text/html\r\n"

"Authorization: Basic %s\r\n"

"\r\n"

,url,webserverip,httpport,net_timeout,auth

);

/*POST /login.php HTTP/1.1 必有字段

Host: www.webserver.com:80 必有字段

User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9) Gecko/2008052906 Firefox/3.0

Accept: text/html,application/xhtml+xml,application/xml;q=0.9,**; q=.2\r\n"); 必有字段

Accept-Language: zh-cn,zh;q=0.5

Accept-Encoding: gzip,deflate

Accept-Charset: gb2312,utf-8;q=0.7,*;q=0.7

Keep-Alive: 300

Connection: keep-alive

Referer: http://www.vckbase.com/
Cookie: ASPSESSIONIDCSAATTCD=DOMMILABJOPANJPNNAKAMCPK

Content-Type: application/x-www-form-urlencoded 必有字段

Content-Length: 79 post方式时必有字段*/

/*GET方式HTTP头写法*/

/*sprintf(header,

"GET /ipnc/php/ipnc.php?%s HTTP/1.1\r\n"

"Host:%s\r\n"

"Content-Type:application/x-www-form-urlencoded\r\n"

"Accept:text/html\r\n"

"\r\n"

,parm,serverip

);*/

}

int parse_response_http_header(const char * all_contents/*接收到的所有内容,包含http头*/,char ** contents/*返回自己需要的内容*/)

{

/**

*根据需求分析网页的内容

**/

return 0;

}

//分析返回的内容的长度

int parse_respose_contents_length(const char * header/*in,http头*/)

{

char * p = (char *)header;

int tmp = 0;

#if 1

if(p)

{

//获取内容长度

while(*p)

{

if(*p == '\r')

{

if(strncasecmp(p,"\r\n\r\n",4) != 0)//http头没有结束

{

p+=2;//过滤\n

if(strncasecmp(p,"Content-Length",14) == 0)

{

while(*p)

{

if(*p == ':')

{

p++;

tmp = atoi(p);

break;

}

p++;

}

break;

}

}

else

{

break;

}

}

p++;

}

if(!tmp)//没有Content-Length字段

{

for(p = (char*)header;*p;p++)

{

if(*p == '\r')

{

if(strncmp(p,"\r\n\r\n",4) == 0)

{

p+=4;

tmp = strlen(p);

break;

}

}

}

}

}

#endif

return tmp;

}

#define HTTP_RECV_BUFFER_SIZE 1024*1024*3 //3MB的接收缓存

#define RECV_BUFF_SIZE 1024

int download_web_page(const char * ipv4/*web server ip地址*/,

unsigned short httpport/*web server 端口*/,

const char * url/*页面相对url,下载的页面为:http://ip/url"*/,

const char * username/*网站认证用户*/,

const char * password/*认证密码*/,

const char * ext_param/*访问网页附加参数*/,

int net_timeout/*网络超时时间,秒*/,

char ** contents/*out:返回的实际内容,无http头,需要使用free函数手动释放空间*/

)

{

#ifdef _WIN32

WSADATA wsaData; //指向WinSocket信息结构的指针

#endif

struct sockaddr_in server_addr;

int sockfd = -1;

char szHttpHeader[1024]={0};

char * pszBuffer = NULL;///堆栈溢出，所以使用堆空间

char szRecvBuffer[RECV_BUFF_SIZE+1]={0};

int len = 0,total_recv_len=0,total_contents_len = 0,re=-1;

unsigned long flags;

fd_set fs;

char * pHttpHeaderEnd = NULL;

#ifdef _WIN32

/*

*这里请注意

*windows下设置接收/发送超时时间时，setsockopt函数对应的超时时间为int型（且超时时间的值的单位为毫秒，当时我直接填写为秒，老是接收超时）

*linux下为struct timeval结构

*/

int timeout = net_timeout*1000;

struct timeval select_timeout={0};

select_timeout.tv_sec=net_timeout;

#else

struct timeval timeout={.tv_sec=net_timeout,.tv_usec=0};

#endif

#ifdef _WIN32

if(WSAStartup(MAKEWORD( 1, 1 ), &wsaData )!=0)//进行WinSocket的初始化

{

WSACleanup();

return -1;//Can't initiates windows socket!初始化失败

}

#endif

if((sockfd = socket(AF_INET,SOCK_STREAM,0)) <= 0)

{

#if defined CONSOLE || defined LINUX

printf("创建socket失败.错误代码:%d,错误原因:%s\n",errno,strerror(errno));

#endif

return -1;//create socket fd failed

}

///设置接收超时时间

if(setsockopt(sockfd,SOL_SOCKET,SO_RCVTIMEO,(char *)&timeout,sizeof(timeout)) != 0)

{

#if defined CONSOLE || defined LINUX

printf("设置socket发送超时时间失败.错误代码:%d,错误原因:%s\n",errno,strerror(errno));

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

return -1;

}

///设置发送超时时间

if(setsockopt(sockfd,SOL_SOCKET,SO_SNDTIMEO,(char *)&timeout,sizeof(timeout)) != 0)

{

#if defined CONSOLE || defined LINUX

printf("设置socket接收超时时间失败.错误代码:%d,错误原因:%s\n",errno,strerror(errno));

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

return -1;

}

///设置非阻塞方式,使用select来判断connect是否超时

#ifdef _WIN32

flags=1;

if( ioctlsocket(sockfd,FIONBIO,&flags) != 0)

#else

flags=fcntl(sockfd,F_GETFL,0);

flags |= O_NONBLOCK;

if( fcntl(sockfd,F_SETFL,flags) != 0)

#endif

{

#if defined CONSOLE || defined LINUX

printf("设置socket为非阻塞失败.错误代码:%d,错误原因:%s\n",errno,strerror(errno));

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

return -1;

}

///设置连接参数

#ifdef _WIN32

memset(&server_addr,0,sizeof(struct sockaddr_in));

#else

bzero(&server_addr,sizeof(struct sockaddr_in));

#endif

server_addr.sin_family = AF_INET;

server_addr.sin_port = htons(httpport);

server_addr.sin_addr.s_addr = inet_addr(ipv4);

///连接服务器

if( connect(sockfd,(struct sockaddr *)&server_addr,sizeof(struct sockaddr_in)) < 0)

{

int ret = 0;

///判断是否超时

FD_ZERO(&fs);

FD_SET(sockfd,&fs);

#ifdef _WIN32

ret = select(sockfd+1,NULL,&fs,NULL,&select_timeout);

#else

ret = select(sockfd+1,NULL,&fs,NULL,&timeout);

#endif

if(ret == 0)//超时

{

#if defined CONSOLE || defined LINUX

printf("链接服务器超时.错误代码:%d,错误原因:%s\n",errno,strerror(errno));

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

return -1;//连接超时

}

else if(ret < 0)///错误

{

#if defined CONSOLE || defined LINUX

printf("链接服务器时发生错误.错误代码:%d,错误原因:%s\n",errno,strerror(errno));

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

return -1;

}

}

///设置为阻塞方式发送和接收数据

#ifdef _WIN32

flags=0;

if( ioctlsocket(sockfd,FIONBIO,&flags) != 0)

#else

flags=fcntl(sockfd,F_GETFL,0);

flags &= ~O_NONBLOCK;

if( fcntl(sockfd,F_SETFL,flags) != 0)

#endif

{

#if defined CONSOLE || defined LINUX

printf("设置socket为阻塞失败.错误代码:%d,错误原因:%s\n",errno,strerror(errno));

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

return -1;//ioctlsocket() error

}

format_http_header(ipv4,httpport,url,username,password,ext_param,net_timeout,szHttpHeader);

len = strlen(szHttpHeader);

///发送http头

if(send(sockfd,szHttpHeader,len,0) != len)

{

#if defined CONSOLE || defined LINUX

printf("发送http头失败.错误代码:%d,错误原因:%s\nhttp头:\n%s\n",errno,strerror(errno),szHttpHeader);

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

return -1;//发送数据失败

}

///准备接收数据

pszBuffer = (char *)malloc(HTTP_RECV_BUFFER_SIZE);

if(!pszBuffer)

{

#if defined CONSOLE || defined LINUX

printf("内存分配失败\n");

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

return -1;//outof memory

}

#ifdef _WIN32

memset(pszBuffer,0,HTTP_RECV_BUFFER_SIZE);

#else

bzero(pszBuffer,HTTP_RECV_BUFFER_SIZE);

#endif

while(1)

{

#ifdef _WIN32

len = recv(sockfd,szRecvBuffer,RECV_BUFF_SIZE,0);

#else

len = recv(sockfd,szRecvBuffer,RECV_BUFF_SIZE,MSG_WAITALL);

#endif

if(len == 0)

{

#if defined CONSOLE || defined LINUX

printf("接收数据超时,超时时间:%d s\n",net_timeout);

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

free(pszBuffer);

return -1;//接收数据超时

}

if(len < 0 )

{

#if defined CONSOLE || defined LINUX

printf("接收数据错误,recv返回值:%d \n",len);

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

free(pszBuffer);

return -1;//timeout

}

//printf("%s",szBuffer);

total_recv_len += len;

if(total_recv_len > (HTTP_RECV_BUFFER_SIZE-1) )

{

#if defined CONSOLE || defined LINUX

printf("接收数据buffer空间不足,当前buffer大小:%d B\n",HTTP_RECV_BUFFER_SIZE-1);

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

free(pszBuffer);

return -1;//not enough buffer size

}

strcat(pszBuffer,szRecvBuffer);

if(len < RECV_BUFF_SIZE)

{

pHttpHeaderEnd = strstr(pszBuffer,"\r\n\r\n");

if(pHttpHeaderEnd )

{

if(!total_contents_len)///http返回头中标示的内容大小

{

total_contents_len = parse_respose_contents_length(pszBuffer);

}

pHttpHeaderEnd += 4;

//如果接收到的内容长度已经达到http返回头中标示的内容大小,停止接收

if( total_contents_len && strlen( pHttpHeaderEnd) >= total_contents_len )

break;

pHttpHeaderEnd = NULL;

}

}

#ifdef _WIN32

memset(szRecvBuffer,0,sizeof(szRecvBuffer));

#else

bzero(szRecvBuffer,sizeof(szRecvBuffer));

#endif

len = 0;

}

if(strcmp(pszBuffer,"") == 0)

{

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

free(pszBuffer);

return -1;//recv data error

}

//printf("%s\n",szBuffer);

* contents = NULL;

re = parse_response_http_header(pszBuffer,contents);

if( re != 0 || !(*contents))

{

if(*contents)

{

free(*contents);

}

#if defined CONSOLE || defined LINUX

printf("分析服务器返回内容失败.返回内容为:\n%s\n",pszBuffer);

#endif

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

free(pszBuffer);

if( -401 == re)

return -1;//用户名/密码无效

return -1;//unknown error

}

#ifdef _WIN32

closesocket(sockfd);

#else

close(sockfd);

#endif

free(pszBuffer);

#ifdef _WIN32

WSACleanup();

#endif

return 0;

}