学步园

CURL 库在使用FTP传输文件时， 正常情况下， ftp的server端都会默认进入根目录 /,   但是当ftp的server端设置了一个子目录，

比如 ftp的server设置了  /data/movies 为第一次默认进入的目录， 则curl的FTP将会无法传输文件， 错误的原因是 ：

ftp的下载地址为  ftp://root:123456@192.168.2.223/data/movies/vbr.ts

而第一次进入的目录为 /data/movies  ， 而curl库的FTP解析ftp地址得出 要进入 data 和movies 目录后才能找到下载的文件，

就会去执行  CWD data   和  CWD movies ， 而在 /data/movies 这个目录去进入  data 目录， 目录肯定是不存在的，

所以出错。

具体的错误现象如下：

* About to connect() to 192.168.2.223 port 21 (#0)<br /> * Trying 192.168.2.223... Leave Lock = Resume Download File</p> <p>* connected<br /> * Connected to 192.168.2.223 (192.168.2.223) port 21 (#0)<br /> < 220 (vsFTPd 2.0.5)<br /> > USER root<br /> < 331 Please specify the password.<br /> > PASS 123456</p> <p>< 230 Login successful.<br /> > PWD<br /> < 257 "/data/movies"<br /> * Entry path is '/data/movies'<br /> > CWD data<br /> < 550 Failed to change directory.<br /> * Server denied you to change to the given directory<br /> * Connection #0 to host 192.168.2.223 left intact<br /> * Access denied to remote resource<br /> > QUIT<br /> < 221 Goodbye.<br /> * Closing connection #0

下面的代码是我使用的代码

void dispatch_threadpool_to_me(void *arg)<br /> {<br /> MissionInfo* pMission = (MissionInfo*)arg;</p> <p> uint64 filelen = 0;<br /> int tries = 0;<br /> CURL *curlhandle;</p> <p>RE_Download:</p> <p> FILE *fp;<br /> curl_off_t local_file_len = -1 ;<br /> uint64 filesize =0 ;<br /> CURLcode result = CURLE_GOT_NOTHING;</p> <p>#ifdef _WIN32<br /> struct _stat file_info;<br /> #else<br /> struct stat file_info;<br /> #endif</p> <p> int use_resume = 0;</p> <p> /* 得到本地文件大小 */<br /> if(stat(pMission->localPath, &file_info) == 0)<br /> {<br /> int flen = file_info.st_size;<br /> if (flen%DOWNLOAD_FILE_SEGMENT == 0)<br /> {<br /> //assert (flen > 0);<br /> local_file_len = flen - DOWNLOAD_FILE_SEGMENT;<br /> }<br /> else<br /> {<br /> local_file_len = flen - flen%DOWNLOAD_FILE_SEGMENT - DOWNLOAD_FILE_SEGMENT;<br /> }<br /> local_file_len = (local_file_len > 0) ? local_file_len : 0;<br /> assert (local_file_len%DOWNLOAD_FILE_SEGMENT == 0);<br /> use_resume = 1;<br /> }</p> <p> if (pMission->missionType == MISSION_TYPE_REMOVEFILE)<br /> { //删除任务<br /> if (use_resume == 0)<br /> {<br /> writelog(LOG_ERROR, "remove file is not exists, path=%s/n", pMission->localPath);<br /> }<br /> unlink(pMission->localPath);<br /> (*pMission->downcbfunc)(pMission->missionID, pMission->missionType, pMission->epgID, 0, "removeFileSuccess", pMission->localPath, 0);<br /> return;<br /> }<br /> curlhandle = curl_easy_init();<br /> if(curlhandle == NULL)<br /> return ;</p> <p> //采用追加方式打开文件，便于实现文件断点续传工作<br /> fp = fopen(pMission->localPath, "ab+");<br /> //ftp服务器可能无法断点续传,所以不能追加写<br /> //fp = fopen(pMission->localPath, "w");<br /> if (fp == NULL)<br /> {<br /> curl_easy_cleanup(curlhandle);<br /> writelog(LOG_ERROR, "Download fopen file Error , file=%s/n", pMission->localPath);<br /> return ;<br /> }</p> <p> curl_easy_setopt(curlhandle, CURLOPT_URL, pMission->remotePath);<br /> curl_easy_setopt(curlhandle, CURLOPT_CONNECTTIMEOUT, 60); // 设置连接超时，单位秒<br /> curl_easy_setopt(curlhandle, CURLOPT_TIMEOUT, 1800);</p> <p> //设置http 头部处理函数<br /> curl_easy_setopt(curlhandle, CURLOPT_HEADERFUNCTION, GetContentLengthFunc);<br /> curl_easy_setopt(curlhandle, CURLOPT_HEADERDATA, &filesize);<br /> // 设置文件续传的位置给libcurl<br /> //use_resume = 0; //服务器不支持断点续传的时候无法续传，所以强制从头开始下载文件<br /> curl_easy_setopt(curlhandle, CURLOPT_RESUME_FROM_LARGE, use_resume?local_file_len:0);<br /> curl_easy_setopt(curlhandle, CURLOPT_WRITEDATA, fp);<br /> curl_easy_setopt(curlhandle, CURLOPT_WRITEFUNCTION, wirtefunc);<br /> curl_easy_setopt(curlhandle, CURLOPT_FTP_USE_EPSV, 0); //EPSV设置为0,就代表启用PASV</p> <p> curl_easy_setopt(curlhandle, CURLOPT_NOPROGRESS, 1L);<br /> #ifdef _DEBUG<br /> curl_easy_setopt(curlhandle, CURLOPT_VERBOSE, 1L);<br /> #endif<br /> result = curl_easy_perform(curlhandle);</p> <p> curl_easy_cleanup(curlhandle);</p> <p> if (result == CURLE_OK)<br /> {<br /> fseek(fp, 0, SEEK_END);<br /> filelen = ftell(fp);<br /> fclose(fp);<br /> writelog(LOG_ERROR, "Success Download File local = %s, remote = %s/n", pMission->localPath, pMission->remotePath);</p> <p> char buffer[512]={0};<br /> if (CompareMD5 (pMission->localPath))<br /> {<br /> const char* p = g_Config.pukkaIndex;<br /> if (*p == '.' || *p == '/')<br /> SNPRINTF (buffer, sizeof(buffer)-1, "%s %s", g_Config.pukkaIndex, pMission->localPath);<br /> else<br /> SNPRINTF (buffer, sizeof(buffer)-1, "./%s %s", g_Config.pukkaIndex, pMission->localPath);<br /> system (buffer);<br /> (*pMission->downcbfunc)(pMission->missionID, pMission->missionType, pMission->epgID, 0, "ok", pMission->localPath, filelen);<br /> return ;<br /> }<br /> else<br /> {</p> <p> }</p> <p> }<br /> else if (result == CURLE_OPERATION_TIMEOUTED)<br /> {<br /> fclose(fp);<br /> writelog(LOG_ERROR, "down operation timeout/n");<br /> goto RE_Download;<br /> }<br /> else if (result == CURLE_COULDNT_CONNECT)<br /> {<br /> writelog(LOG_ERROR, "Can not Connect FTP File local = %s, remote = %s/n", pMission->localPath, pMission->remotePath);<br /> (*pMission->downcbfunc)(pMission->missionID, pMission->missionType, pMission->epgID, -1, curl_easy_strerror(result), pMission->localPath, filelen);<br /> return ;<br /> }<br /> else<br /> {<br /> fclose(fp);<br /> tries ++;<br /> if (tries < MAX_TRY_DOWNLOAD_COUNT)<br /> {<br /> //writelog(LOG_ERROR, "Download File Try = %d /n localdir = %s /n remotedir = %s /n err=%s/n",<br /> // tries, pMission->localPath, pMission->remotePath, curl_easy_strerror(result));<br /> sleep(MAX_SLEEP_TIME);<br /> if (result == CURLE_BAD_DOWNLOAD_RESUME)<br /> {<br /> unlink(pMission->localPath);//不能断点续传下载，则删除本地已经下载的部分文件<br /> }<br /> goto RE_Download;<br /> }<br /> else if (tries == MAX_TRY_DOWNLOAD_COUNT)<br /> {//万一ftp的服务器不支持断点续传，所以重新把文件删除， 在下载一次<br /> tries++;<br /> unlink(pMission->localPath);<br /> goto RE_Download;<br /> }<br /> else<br /> {<br /> writelog(LOG_ERROR, "Fail Download File local = %s, remote = %s/n", pMission->localPath, pMission->remotePath);<br /> (*pMission->downcbfunc)(pMission->missionID, pMission->missionType, pMission->epgID, -1, curl_easy_strerror(result), pMission->localPath, filelen);<br /> return ;<br /> }<br /> }<br /> }<br />

修改方法是  修改 curl库目录下面 lib文件夹下面的 ftp.c 文件

在函数 static CURLcode ftp_parse_url_path(struct connectdata *conn) 中 添加如下代码

if (ftpc->dirdepth == 0)<br /> {<br /> ftpc->dirs[0] = strdup("/");<br /> ftpc->dirdepth++;<br /> }

意思就是 让ftp客户端从 根目录开始一级一级的进入到文件所在的目录。

添加的位置如下 ：

default: /* allow pretty much anything */<br /> case FTPFILE_MULTICWD:<br /> ftpc->dirdepth = 0;<br /> ftpc->diralloc = 5; /* default dir depth to allocate */<br /> ftpc->dirs = calloc(ftpc->diralloc, sizeof(ftpc->dirs[0]));<br /> if(!ftpc->dirs)<br /> return CURLE_OUT_OF_MEMORY;</p> <p> /* we have a special case for listing the root dir only */<br /> if(strequal(path_to_use, "/"))<br /> {<br /> cur_pos++; /* make it point to the zero byte */<br /> ftpc->dirs[0] = strdup("/");<br /> ftpc->dirdepth++;<br /> }<br /> else<br /> {</p> <p> /* parse the URL path into separate path components */<br /> while((slash_pos = strchr(cur_pos, '/')) != NULL)<br /> {<br /> /* 1 or 0 pointer offset to indicate absolute directory */<br /> ssize_t absolute_dir = ((cur_pos - data->state.path > 0) && (ftpc->dirdepth == 0))?1:0;</p> <p> if (ftpc->dirdepth == 0)<br /> {<br /> ftpc->dirs[0] = strdup("/");<br /> ftpc->dirdepth++;<br /> }</p> <p> /* seek out the next path component */<br /> if(slash_pos-cur_pos)<br /> {<br /> /* we skip empty path components, like "x//y" since the FTP command<br /> CWD requires a parameter and a non-existant parameter a) doesn't<br /> work on many servers and b) has no effect on the others. */<br /> int len = (int)(slash_pos - cur_pos + absolute_dir);<br /> ftpc->dirs[ftpc->dirdepth] = curl_easy_unescape(conn->data, cur_pos - absolute_dir, len, NULL);<br /> if(!ftpc->dirs[ftpc->dirdepth])<br /> { /* run out of memory ... */<br /> failf(data, "no memory");<br /> freedirs(ftpc);<br /> return CURLE_OUT_OF_MEMORY;<br /> }</p> <p> if(isBadFtpString(ftpc->dirs[ftpc->dirdepth]))<br /> {<br /> free(ftpc->dirs[ftpc->dirdepth]);<br /> freedirs(ftpc);<br /> return CURLE_URL_MALFORMAT;<br /> }<br /> }<br /> else<br /> {<br /> cur_pos = slash_pos + 1; /* jump to the rest of the string */<br /> continue;<br /> }</p> <p> cur_pos = slash_pos + 1; /* jump to the rest of the string */<br /> if(++ftpc->dirdepth >= ftpc->diralloc)<br /> {<br /> /* enlarge array */<br /> char *bigger;<br /> ftpc->diralloc *= 2; /* double the size each time */<br /> bigger = realloc(ftpc->dirs, ftpc->diralloc * sizeof(ftpc->dirs[0]));<br /> if(!bigger)<br /> {<br /> freedirs(ftpc);<br /> return CURLE_OUT_OF_MEMORY;<br /> }<br /> ftpc->dirs = (char **)bigger;<br /> }<br /> }<br /> }<br /> filename = cur_pos; /* the rest is the file name */<br /> break;<br /> } /* switch */