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  • 上传文件块client实现


    首先由内容阻止所有文件(块大小的约束),然后对于每一个chunk构造单独的一个UDP 数据报进行传输,在应用层的開始是自己定义的包头,有块号,块长度,块指纹等元数据信息,这些信息便于接收端可以按序正确接收。


    /*--vonzhou
     ---this project is to upload file after chunking using 
        rabin fingerprint, here use UDP so that every packet nodelay.
        but we need to ensure the reliability.
    
    */
    
    #include "global.h"
    
    #define SERV_PORT 2500
    
    typedef struct {
            unsigned char fp[20];
            int chunk_id;
            short flags;
            short chunk_len; // The max is 32767 enough
            char data[MAX_CHUNK_SIZE];
    }TransferUnit;
    
    // some flags for this chunk transfered.
    enum{
            CHUNK_NEED_DEDU = 0x0001,   // need deduplication
            CHUNK_OTHER = 0x0002      // other for extension
    };
    
    FileInfo *fi;
    
    int sendUDP(FileInfo *fi,int sockfd,struct sockaddr *pservaddr,socklen_t servlen){
        char buf[sizeof(TransferUnit)];
        fd_set wrset;
        struct timeval tv;
        int rlen,wlen, len = 1;
        int fd;
        int ret;
        int i,j;
        FingerChunk *p;
        TransferUnit unit;
    
        //connect to server
        if(connect(sockfd,(struct sockaddr *)pservaddr,servlen) == -1)
            err_quit("connet error");
        else
            printf("connect server ok!
    ");
    
        fd = open(fi->file_path, O_RDONLY);
        if(fd==-1)
            err_quit("fopen error %s
    ",strerror(errno));
    
        // begin to transfer the file to the server;            
        i=0;
        p = fi->first;
    
        while(1){
            tv.tv_sec = 1;// tell select to wait 1 second;
            tv.tv_usec = 0;
    
            FD_ZERO(&wrset);
            FD_SET(sockfd,&wrset);
            // wait for the socket can write        
            ret = select(sockfd+1,NULL,&wrset,NULL,&tv);
            if(ret == -1)
                err_quit("select error %s
    ",strerror(errno));
            else if(ret==0){
                printf("select timeout,continue circle
    ");
                continue;
            }
    
            //prepare for writing the socket        
            memset(&unit, 0, sizeof(unit));
            if(FD_ISSET(sockfd,&wrset)){
                /* we should first transfer some medadata,like filename,filter feature vector,
                *FIXME: file fingerprint to controller?

    to make a packetin, *here just let the fp = 20 1s */ if(i == 0){ for(j=0;j<20;j++) unit.fp[j] = 0xff; unit.chunk_id = 0; //need not dedu unit.chunk_len = strlen(fi->file_path); wlen = write(sockfd, &unit, 28 + strlen(fi->file_path)); if(wlen != (28 + strlen(fi->file_path))) err_quit("write data to sockfd error:%s ",strerror(errno)); memset(&unit, 0, sizeof(unit)); } if(p != NULL) len = p->chunklen; // the last read , p is null, so cannnot use p->chu rlen = read(fd, unit.data, len); if(rlen < 0) err_quit("fread data error %s ",strerror(errno)); else if(rlen==0){ //indicate the transfer completed for(j=0;j<20;j++) unit.fp[j] = 0xff; unit.chunk_id = 0; //need not dedu unit.chunk_len = 3; strncpy(unit.data,"end", 3); wlen = write(sockfd,&unit,28 + 3); if(wlen !=31) err_quit("write end flag error:%s ",strerror(errno)); printf("File %s Transfer Success! ", fi->file_path); close(fd); return 0; } // construct this tranfer unit we cannot before read //bcos the following p pointer used. for(j=0; j< 20;j++) unit.fp[j] = p->chunk_hash[j];// 20B fingerprint; unit.chunk_id = i; // 4B chunk ID unit.chunk_len = p->chunklen; unit.flags = CHUNK_NEED_DEDU; //write to socket wlen = write(sockfd, &unit, 28+p->chunklen); if(wlen != (rlen + 28)) err_quit("write data to sockfd error:%s ",strerror(errno)); i++; p = p->next; memset(&unit, 0, sizeof(unit)); usleep(500); printf("The %d times read ",i); } }// end while(1) } int main(int argc ,char *argv[]) { char *fh; struct sysinfo s_info; long time1,time2; int error1,error2; int sockfd; struct stat fsize; struct sockaddr_in servaddr; error1= sysinfo(&s_info); time1 = s_info.uptime; int r; // FileInfo *fi; fi = file_new(); if(argc != 3) err_quit("useage:udpclient<IPaddress>; "); bzero(&servaddr,sizeof(servaddr)); servaddr.sin_family= AF_INET; servaddr.sin_port = htons(SERV_PORT); if(inet_pton(AF_INET,argv[1],&servaddr.sin_addr) <= 0) err_quit("[%s]is not a valid IPaddress ",argv[1]); sockfd =socket(AF_INET,SOCK_DGRAM,0); r = fcntl(sockfd, F_GETFL, 0); fcntl(sockfd, F_SETFL, r & ~O_NONBLOCK); // chunking file strcpy(fi->file_path, argv[2]); chunk_file(fi); printf("File size : %lld ",fi->file_size); printf("Chunk Num : %d ",fi->chunknum); sendUDP(fi, sockfd, (struct sockaddr *)&servaddr,sizeof(servaddr)); close(sockfd); fprintf(stderr,"ServerIP: %s ",argv[1]); if(stat(argv[2],&fsize) == -1) perror("failed to get fiel statusi "); else fprintf(stderr,"file name: %s file size: %dK ",argv[2],fsize.st_size/1024); error2=sysinfo(&s_info); time2 = s_info.uptime; printf("tranfice file time =%ld seconds ",(time2-time1)); }


    转载请注明出处:http://blog.csdn.net/vonzhoufz/article/details/31429585

    版权声明:本文博客原创文章,博客,未经同意,不得转载。

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  • 原文地址:https://www.cnblogs.com/yxwkf/p/4711715.html
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