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!\n");

    fd = open(fi->file_path, O_RDONLY);
    if(fd==-1)
        err_quit("fopen error %s\n",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\n",strerror(errno));
        else if(ret==0){
            printf("select timeout,continue circle\n");
            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\n",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\n",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\n",strerror(errno));                printf("File %s Transfer Success!\n", 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\n",strerror(errno));            i++;            p = p->next;            memset(&unit, 0, sizeof(unit));            usleep(500);            printf("The %d times read\n",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>;\n");        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\n",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\n",fi->file_size);        printf("Chunk Num : %d\n",fi->chunknum);        sendUDP(fi, sockfd, (struct sockaddr *)&servaddr,sizeof(servaddr));        close(sockfd);        fprintf(stderr,"ServerIP:\t%s\n",argv[1]);        if(stat(argv[2],&fsize) == -1)                perror("failed to get fiel statusi\n");        else                fprintf(stderr,"file name:\t%s\nfile size:\t%dK\n",argv[2],fsize.st_size/1024);        error2=sysinfo(&s_info);        time2 = s_info.uptime;        printf("tranfice file time =%ld seconds\n",(time2-time1));}

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