HTTP下载

 

#include <stdio.h>#include <winsock2.h>#pragma comment(lib,"Ws2_32.lib")int main(){WSADATA wsa;WSAStartup(MAKEWORD(2,2),&wsa);SOCKET serverSocket;serverSocket=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);struct sockaddr_in serverAddress;memset(&serverAddress,0,sizeof(sockaddr_in));serverAddress.sin_family=AF_INET;serverAddress.sin_addr.S_un.S_addr = inet_addr("74.125.71.147");//serverAddress.sin_addr.S_un.S_addr = inet_addr("211.100.26.77");serverAddress.sin_port = htons(80);connect(serverSocket,(struct sockaddr*)&serverAddress,sizeof(serverAddress)); char * msgHttpRequest = "GET http://portablecb.googlecode.com/files/LoveDEV.7z HTTP/1.1/r/n" "Host:google.comt/r/n" "Accept:*/* /r/n/r/n";FILE *fp;fp = fopen("l.jpg","w+"); int nCount = 0;int nTimes = 1;while (nTimes--){send(serverSocket,msgHttpRequest,strlen(msgHttpRequest),0);Sleep(3100);char recvBuff[1024] = { 0 };int ret = 0;while (1){//记得检查HTTP的状态memset(recvBuff,0,1024);ret = recv(serverSocket,recvBuff,1024,0);if( ret < 0){closesocket(serverSocket);break;}if( ret == 0 ){break;}printf("%s/n",recvBuff);}char * pCharFind = NULL;pCharFind = strstr(recvBuff,"bytes");int len = pCharFind - recvBuff;len += 4;int recvLen = strlen(recvBuff);fwrite((void*)(recvBuff + len),strlen(recvBuff) - len,strlen(recvBuff) -len,fp);fflush(fp);fclose(fp);printf("len:%d/n%s/n",recvLen,recvBuff);printf("----------------------------------------");printf("%d/n/n",nCount++);Sleep(100);}return 0;}===================================================#include <string>#include <iostream>#include <stdio.h>#include <winsock.h>#include <conio.h>using namespace std;#pragma comment("ws2_32.lib")string host2ip(const string& strdomain);void save2file(char *buffer,const string& filename);int getlength(const string& sheader);bool getstatus(const string& sheader);int getleftlength(const string& sheader);void sethttphead(const string& file,const string& server);int port = 80;int error=0;string serveraddr;int i = 0;const int BUFFER_SIZE = 1024;char buffer[BUFFER_SIZE] = {0};char msg[BUFFER_SIZE];FILE *f;const string file = "/BT/200801/3/117906.torrent";const string url = "www.supbt.com";const string filename = "117906.torrent";int main(void){ int r; WSADATA wsa; SOCKET sock; struct sockaddr_in sin; f = fopen(filename.c_str(),"ab"); sethttphead(file,url); if(WSAStartup(MAKEWORD(2,2),&wsa)) { printf("WSAStartup Error: %d/n",WSAGetLastError()); getche(); return -1; } if((sock=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP))==INVALID_SOCKET) { printf("Socket Error: %d/n",WSAGetLastError()); getche(); return -1; } sin.sin_family=AF_INET; sin.sin_port=htons(port); serveraddr = host2ip(url); cout << serveraddr << endl; sin.sin_addr.s_addr=inet_addr(serveraddr.c_str()); if(connect(sock,(struct sockaddr *)&sin,sizeof(sin))==SOCKET_ERROR) { printf("Connect Error: %d/n",WSAGetLastError()); printf("请检测网络连接！/n"); getche(); return -1; } if((r=send(sock,msg,sizeof(msg),0))==SOCKET_ERROR) { printf("Send Error: %d/n",WSAGetLastError()); getche(); return -1; } memset(buffer,0,BUFFER_SIZE); if((r=recv(sock,buffer,BUFFER_SIZE,0))==SOCKET_ERROR) { printf("Recv Error: %d/n",WSAGetLastError()); closesocket(sock); return -1; } string header = string(buffer); int ilength = getlength(header); int leftlength = ilength; int icount; if(getstatus(header)){ //current is r char *q = buffer; char *p = strstr(buffer, "/r/n/r/n"); p += 4; //注意这里得 r - (p-q) 非常关键得问题 fwrite(p,r - (p - q),1,f); leftlength -= r - (p - q); int i=0; icount = r - (p - q); while(true) { memset(buffer, 0, BUFFER_SIZE); r = recv(sock, buffer, BUFFER_SIZE, 0); if (r < 0) { closesocket(sock); return 2; } if (r == 0) { break; } int tmp; tmp = leftlength; //209 100 100 92 leftlength -= r; if(leftlength > 0){ fwrite(buffer,r,1,f); icount += r; } else if(leftlength == 0){ // break; } else{ icount += tmp; fwrite(buffer,tmp,1,f); break; } cout << i++ << " r is "<< r << endl; } }else{ cout << "http protocal error" << endl; } cout << icount << endl; fclose(f); closesocket(sock); WSACleanup(); getche(); return 0;}/*构造HTTP头*/void sethttphead(const string& file,const string& server){ strcat(msg,"GET "); strcat(msg,file.c_str()); strcat(msg," HTTP/1.1"); strcat(msg,"/r/n"); strcat(msg,"Accept:*/*"); strcat(msg,"/r/n"); //strcat(msg,"Accept-Language: zh-cn"); //strcat(msg,"/r/n"); //strcat(msg,"Accept-Encoding: gzip, deflate"); //strcat(msg,"/r/n"); strcat(msg,"User-Agent: Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)"); strcat(msg,"/r/n"); strcat(msg,"Host:"); strcat(msg,server.c_str()); strcat(msg,"/r/n"); strcat(msg,"Connection: Keep-Alive"); strcat(msg,"/r/n"); strcat(msg,"/r/n");}//---------------------------------------------------------------------------/*将domain 转换为IP地址*/string host2ip(const string& strdomain){ SOCKADDR_IN saddr; WORD wVersionRequested; WSADATA wsaData; hostent *pHostIp; int nErrorNum; wVersionRequested = MAKEWORD(2, 2); nErrorNum = WSAStartup(wVersionRequested, &wsaData); if(nErrorNum != 0) { return ""; } saddr.sin_family = AF_INET; pHostIp = gethostbyname(strdomain.c_str()); if(pHostIp == NULL) { return "0.0.0.0"; } WSACleanup(); return (string)inet_ntoa(*(LPIN_ADDR)*(pHostIp->h_addr_list));}/*该方法为测试用法，并为应用到项目中*/void save2file(char *buffer,const string& filename){ FILE *f; f = fopen(filename.c_str(),"a+"); fwrite(buffer,strlen(buffer),1,f); fclose(f);}/*该方法获取待下载文件大小*/int getlength(const string& sheader){ char * cont_len_pos; unsigned long cont_length; const char* header = sheader.c_str(); cont_len_pos =(char *)strstr(header,"Content-Length:"); cont_len_pos = (char *)strchr(cont_len_pos,' '); cont_len_pos++; sscanf(cont_len_pos, "%ld", &cont_length); return cont_length;}/*该方法判断是否Get成功，不成功就取消下载文件*/bool getstatus(const string& sheader){ string start = "HTTP/1.1 200 OK"; if(sheader.find(start,0) != string::npos){ return true; } else{ return false; }}/*该方法并没有用到，开始考虑多了*/int getleftlength(const string& sheader){ int nreturnl = 0; int ilength = sheader.length(); string _send = "/r/n/r/n"; int istart = sheader.find_last_of(_send); if(istart != string::npos){ nreturnl = ilength - istart -_send.length(); } return nreturnl;}