linux_http.rar_linux http 下载

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include <sys/socket.h> #include <errno.h> #include <unistd.h> #include <netinet/in.h> #include <limits.h> #include <netdb.h> #include <arpa/inet.h> #include <ctype.h> /************************************************************** 功能：从字符串src中分析出网站地址和端口，并得到用户要下载的文件 ***************************************************************/ void GetHost(char * src, char * web, char * file, int * port) { char * pA; char * pB; memset(web, 0, sizeof(web)); memset(file, 0, sizeof(file)); *port = 0; if(!(*src)) return; pA = src; if(!strncmp(pA , "http://" , strlen("http://"))) pA = src + strlen("http://"); else if(!strncmp(pA , "https://" , strlen("https://"))) pA = src + strlen("https://"); pB = strchr(pA, '/'); if(pB){ memcpy(web, pA, strlen(pA) - strlen(pB)); if(pB+1){ memcpy(file, pB + 1, strlen(pB) - 1); file[strlen(pB) - 1] = 0; } } else memcpy(web, pA, strlen(pA)); if(pB) web[strlen(pA) - strlen(pB)] = 0; //web字符串结尾为0 else web[strlen(pA)] = 0; //web字符串结尾为0 pA = strchr(web, ':'); if(pA) *port = atoi(pA + 1); else *port = 80; } int main (int argc, char *argv[]) { int sockfd; int read_t,start_text; char buffer[1024]; struct sockaddr_in server_addr; struct hostent *host; int portnumber,nbytes; char host_addr[256]; char host_file[1024]; char local_file[256]; char request[1024]; int send, totalsend; int i; FILE *fp; char *data_p; char url[128]; memset(url,0,128); sprintf(url , argv[1]); /*分析网址、端口、文件名等*/ GetHost(url, host_addr, host_file, &portnumber); printf("webhost:%s\n", host_addr); printf("hostfile:%s\n", host_file); printf("portnumber:%d\n\n", portnumber); /*取得主机IP地址*/ if((host=gethostbyname(host_addr))==NULL){ fprintf(stderr,"Gethostname error, %s\n", strerror(errno)); exit(1); } /* 客户程序开始建立 sockfd描述符 */ /*建立SOCKET连接*/ if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1) { fprintf(stderr,"Socket Error:%s\a\n",strerror(errno)); exit(1); } /* 客户程序填充服务端的资料 */ bzero(&server_addr,sizeof(server_addr)); server_addr.sin_family=AF_INET; server_addr.sin_port=htons(portnumber); server_addr.sin_addr=*((struct in_addr *)host->h_addr); //地址表的第一行 /* 客户程序发起连接请求 */ /* 连接网站*/ if(connect(sockfd,(struct sockaddr *)(&server_addr),sizeof(server_addr))==-1) { fprintf(stderr,"Connect Error:%s\a\n",strerror(errno)); exit(1); } printf("connect success!\n"); sprintf(request, "GET /%s HTTP/1.1\r\nAccept: */*\r\nAccept-Language: zh-cn\r\n\ User-Agent: Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)\r\n\ Host: %s:%d\r\nConnection: Close\r\n\r\n", host_file, host_addr, portnumber); printf("%s", request);/*准备request，将要发送给主机*/ /*发送http请求request*/ send = 0;totalsend = 0; nbytes=strlen(request); while(totalsend < nbytes) { send = write(sockfd, request + totalsend, nbytes - totalsend); if(send==-1) { printf("send error!%s\n", strerror(errno)); exit(0); } totalsend+=send; printf("%d bytes send OK!\n", totalsend); } printf("\nThe following is the response header:\n"); i=0; //sleep(2); /* 连接成功了，接收http响应，response */ read_t = read(sockfd,buffer,1024); //服务器那边要写了才能读 不然堵塞 printf("the buffer is %s\n",buffer); data_p = strstr(buffer,"\r\n\r\n"); if(data_p == NULL){ printf("Not Header data!\n"); return -1; } printf("the data_p is %x:%x\n",data_p[0],data_p[4]); //检查下 fp = fopen("baidu.html","w+"); if(fp == NULL){ perror("fopen"); return -1; } data_p += 4; printf("the first len is %d\n",read_t - (data_p - buffer)); //buffer是首地址 fwrite(data_p,1,read_t - (data_p - buffer),fp); //read_t-data_p..是除\r\n\r\n后的数据长度 while(1){ read_t = read(sockfd,buffer,1024); //先读到内存 if(read_t == 0) break; fwrite(buffer,1,read_t,fp); //再写到文件中 } fclose(fp); close(sockfd); exit(0); }