Libcurl 从FTP服务器下载

#include <stdlib.h>#include <stdio.h>#include <curl/curl.h>#include <sys/stat.h>/* parse headers for Content-Length */size_t getcontentlengthfunc(void *ptr, size_t size, size_t nmemb, void *stream) {    int r;    long len = 0;    /* _snscanf() is Win32 specific */    //r = _snscanf(ptr, size * nmemb, "Content-Length: %ld\n", &len);    r = sscanf((const char*)ptr, "Content-Length: %ld\n", &len);    if (r) /* Microsoft: we don't read the specs */        *((long *) stream) = len;    return size * nmemb;}/* discard downloaded data */size_t discardfunc(void *ptr, size_t size, size_t nmemb, void *stream) {    return size * nmemb;}//write data to uploadsize_t writefunc(void *ptr, size_t size, size_t nmemb, void *stream){    return fwrite(ptr, size, nmemb, (FILE*)stream);}/* read data to upload */size_t readfunc(void *ptr, size_t size, size_t nmemb, void *stream){    FILE *f = (FILE*)stream;    size_t n;    if (ferror(f))        return CURL_READFUNC_ABORT;    n = fread(ptr, size, nmemb, f) * size;    return n;}int upload(CURL *curlhandle, const char * remotepath, const char * localpath, long timeout, long tries){    FILE *f;    long uploaded_len = 0;    CURLcode r = CURLE_GOT_NOTHING;    int c;    f = fopen(localpath, "rb");    if (f == NULL) {        perror(NULL);        return 0;    }    curl_easy_setopt(curlhandle, CURLOPT_UPLOAD, 1L);    curl_easy_setopt(curlhandle, CURLOPT_URL, remotepath);    curl_easy_setopt(curlhandle, CURLOPT_USERPWD, "spider:spider");       if (timeout)        curl_easy_setopt(curlhandle, CURLOPT_FTP_RESPONSE_TIMEOUT, timeout);    curl_easy_setopt(curlhandle, CURLOPT_HEADERFUNCTION, getcontentlengthfunc);    curl_easy_setopt(curlhandle, CURLOPT_HEADERDATA, &uploaded_len);    curl_easy_setopt(curlhandle, CURLOPT_WRITEFUNCTION, discardfunc);    curl_easy_setopt(curlhandle, CURLOPT_READFUNCTION, readfunc);    curl_easy_setopt(curlhandle, CURLOPT_READDATA, f);    curl_easy_setopt(curlhandle, CURLOPT_FTPPORT, "-"); /* disable passive mode */    curl_easy_setopt(curlhandle, CURLOPT_FTP_CREATE_MISSING_DIRS, 1L);    curl_easy_setopt(curlhandle, CURLOPT_VERBOSE, 1L);    for (c = 0; (r != CURLE_OK) && (c < tries); c++) {        /* are we resuming? */        if (c) { /* yes */            /* determine the length of the file already written */            /*            * With NOBODY and NOHEADER, libcurl will issue a SIZE            * command, but the only way to retrieve the result is            * to parse the returned Content-Length header. Thus,            * getcontentlengthfunc(). We need discardfunc() above            * because HEADER will dump the headers to stdout            * without it.            */            curl_easy_setopt(curlhandle, CURLOPT_NOBODY, 1L);            curl_easy_setopt(curlhandle, CURLOPT_HEADER, 1L);            r = curl_easy_perform(curlhandle);            if (r != CURLE_OK)                continue;            curl_easy_setopt(curlhandle, CURLOPT_NOBODY, 0L);            curl_easy_setopt(curlhandle, CURLOPT_HEADER, 0L);            fseek(f, uploaded_len, SEEK_SET);            curl_easy_setopt(curlhandle, CURLOPT_APPEND, 1L);        }        else { /* no */            curl_easy_setopt(curlhandle, CURLOPT_APPEND, 0L);        }        r = curl_easy_perform(curlhandle);    }    fclose(f);    if (r == CURLE_OK)        return 1;    else {        fprintf(stderr, "%s\n", curl_easy_strerror(r));        return 0;    }}// 下载int download(CURL *curlhandle, const char * remotepath, const char * localpath, long timeout, long tries){    FILE *f;    curl_off_t local_file_len = -1 ;    long filesize =0 ;    CURLcode r = CURLE_GOT_NOTHING;    struct stat file_info;    int use_resume = 0;    //获取本地文件大小信息    if(stat(localpath, &file_info) == 0)    {        local_file_len = file_info.st_size;         use_resume = 1;    }    //追加方式打开文件，实现断点续传    f = fopen(localpath, "ab+");    if (f == NULL) {        perror(NULL);        return 0;    }    curl_easy_setopt(curlhandle, CURLOPT_URL, remotepath);    curl_easy_setopt(curlhandle, CURLOPT_USERPWD, "spider:spider");//用户名跟密码       //连接超时设置    curl_easy_setopt(curlhandle, CURLOPT_CONNECTTIMEOUT, timeout);    //设置头处理函数    curl_easy_setopt(curlhandle, CURLOPT_HEADERFUNCTION, getcontentlengthfunc);    curl_easy_setopt(curlhandle, CURLOPT_HEADERDATA, &filesize);    // 设置断点续传    curl_easy_setopt(curlhandle, CURLOPT_RESUME_FROM_LARGE, use_resume?local_file_len:0);    curl_easy_setopt(curlhandle, CURLOPT_WRITEFUNCTION, writefunc);    curl_easy_setopt(curlhandle, CURLOPT_WRITEDATA, f);    curl_easy_setopt(curlhandle, CURLOPT_NOPROGRESS, 1L);    curl_easy_setopt(curlhandle, CURLOPT_VERBOSE, 1L);    r = curl_easy_perform(curlhandle);    fclose(f);    if (r == CURLE_OK)        return 1;    else {        fprintf(stderr, "%s\n", curl_easy_strerror(r));        return 0;    }}int main(int c, char **argv) {    CURL *curlhandle = NULL;    CURL *curldwn = NULL;    curl_global_init(CURL_GLOBAL_ALL);    curlhandle = curl_easy_init();    curldwn = curl_easy_init();    upload(curlhandle, "ftp://192.168.0.185/a/success", "D:/abc.jpg", 1, 3);    download(curldwn, "ftp://192.168.2.21/wlw/eclipse-standard-luna-R-win32-x86_64.zip", "D:/123.zip", 1, 3);    curl_easy_cleanup(curlhandle);    curl_easy_cleanup(curldwn);    curl_global_cleanup();    return 0;}