libcurl之ftp上传 & 下载 （转）

源地址：http://my.oschina.net/pathenon/blog/66154

由于项目的需要，利用libcurl编写程序与ftp服务器通信，进行文件上传或下载，愈发地感到curl功能的强悍。其实在命令行下直接使用curl命令就可以完成这些功能，但是需要获取上传下载行为的状态以便更好地控制。直接上代码：

#ifndef _FTP_MANAGER_H_
#define _FTP_MANAGER_H_
 
/*FTP OPERATION CODE*/
typedef enum FTP_STATE
{
    FTP_UPLOAD_SUCCESS,
    FTP_UPLOAD_FAILED,
    FTP_DOWNLOAD_SUCCESS,
    FTP_DOWNLOAD_FAILED 
}FTP_STATE;
 
/*FTP OPERATIONS OPTIONS*/
typedef struct FTP_OPT
{
    char *url;      /*url of ftp*/
    char *user_key;     /*username:password*/
    char *file;     /*filepath*/
}FTP_OPT;
 
#ifdef __cplusplus
    extern "C" {
#endif
 
/*upload file to ftp server*/
FTP_STATE ftp_upload(const FTP_OPT ftp_option);
 
/*download file from ftp server*/
FTP_STATE ftp_download(const FTP_OPT ftp_option);
 
#ifdef __cplusplus
    }
#endif
 
#endif

//ftp-manager.c
 
#include 
#include 
#include 
 
#include "ftp-manager.h"
 
/*****************util api******************/
int get_file_size(FILE *file)
{
    int size = 0;
    fseek(file, 0L, SEEK_END);
    size = ftell(file);
    fseek(file, 0L, SEEK_SET);
    return size;
}
 
/******************curl api****************/
CURL *curl_init()
{
    curl_global_init(CURL_GLOBAL_DEFAULT); 
    CURL *curl = curl_easy_init();
    if(NULL == curl)
    {
        fprintf(stderr, "Init curl failed.\n");
        exit(1);
    }
    return curl;
}
 
void curl_set_upload_opt(CURL *curl, const char *url, const char *user_key, FILE *file)
{
    curl_easy_setopt(curl, CURLOPT_URL, url);
    curl_easy_setopt(curl, CURLOPT_USERPWD, user_key);
    curl_easy_setopt(curl, CURLOPT_READDATA, file); 
    curl_easy_setopt(curl, CURLOPT_UPLOAD, 1);
    curl_easy_setopt(curl, CURLOPT_INFILESIZE, get_file_size(file));
    curl_easy_setopt(curl, CURLOPT_FTP_CREATE_MISSING_DIRS, 1);
//  curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
}
 
void curl_set_download_opt(CURL *curl, const char *url, const char *user_key, FILE *file)
{
    curl_easy_setopt(curl, CURLOPT_URL, url);
    curl_easy_setopt(curl, CURLOPT_USERPWD, user_key);
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, file);
//  curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
}
 
void curl_exit(CURL *curl)
{
    curl_easy_cleanup(curl);
    curl_global_cleanup(); 
}
 
CURLcode curl_perform(CURL *curl)
{
    CURLcode ret = curl_easy_perform(curl);
    if(ret != 0)
    {
        fprintf(stderr, "Perform curl failed.\n");
        curl_exit(curl);
        exit(1);
    }
    return ret;
}
 
/****************ftp upload & download api******************/
FTP_STATE ftp_upload(const FTP_OPT ftp_option)
{
    FTP_STATE state;
    CURL *curl;;
    FILE *fp = fopen(ftp_option.file, "r");
    if(NULL == fp)
    {
        fprintf(stderr, "Open file failed at %s:%d\n", __FILE__, __LINE__);
        return FTP_UPLOAD_FAILED;
    }
 
    curl = curl_init();
    curl_set_upload_opt(curl, ftp_option.url, ftp_option.user_key, fp);
    if(CURLE_OK == curl_perform(curl))
        state = FTP_UPLOAD_SUCCESS;
    else
        state = FTP_UPLOAD_FAILED;
 
    curl_exit(curl);
    fclose(fp);
    return state;
}
 
FTP_STATE ftp_download(const FTP_OPT ftp_option)
{
    FTP_STATE state;
    CURL *curl;
    FILE *fp = fopen(ftp_option.file, "w");
    if(NULL == fp)
    {
        fprintf(stderr, "Open file failed at %s:%d\n", __FILE__, __LINE__);
        return FTP_UPLOAD_FAILED;
    }
 
    curl = curl_init();
    curl_set_download_opt(curl, ftp_option.url, ftp_option.user_key, fp);
    if(CURLE_OK == curl_perform(curl))
        state = FTP_DOWNLOAD_SUCCESS;
    else
        state = FTP_DOWNLOAD_FAILED;
 
    curl_exit(curl);
    fclose(fp);
    return state;
}

//test.c
 
#include 
 
#include "ftp-manager.h"
 
int main()
{
    FTP_OPT ftp_opt;
    ftp_opt.url = "ftp://127.0.0.1//var/ftp/upload.txt";
    ftp_opt.user_key = "xxx:xxx";
    ftp_opt.file = "/home/xxx/project/ftpManager/upload.txt";
 
    if(FTP_UPLOAD_SUCCESS == ftp_upload(ftp_opt))
        printf("Upload success.\n");
    else
        printf("Upload failed.\n");
 
    ftp_opt.url = "ftp://127.0.0.1//var/ftp/download.txt";
    ftp_opt.file = "/home/xxx/project/ftpManager/download.txt";
 
    if(FTP_DOWNLOAD_SUCCESS == ftp_download(ftp_opt))
        printf("Download success.\n");
    else
        printf("Download failed.\n");
 
    return 0;
}