C语言 HTTP上传文件-利用libcurl库上传文件

from :  http://www.cnblogs.com/lidabo/p/4159574.html

size_t FileTransferModule_Impl::writeData(char *ptr, size_t size, size_t nmemb, std::string *stream)
{
stream->append(ptr, size*nmemb);
return nmemb*size;
}

BOOL FileTransferModule_Impl::sendFile(IN const CString& sFilePath, IN const std::string& sSendToSID)
{
if (TransferFileEntityManager::getInstance()->checkIfIsSending(sFilePath))
{
return FALSE;
}


CURL *curl;
CURLMcode res;
CURLM *multi_handle;
int still_running;


struct curl_httppost *formpost = NULL;
struct curl_httppost *lastptr = NULL;
struct curl_slist *headerlist = NULL;
static const char buf[] = "Expect:";


std::string strJosn;
/* Fill in the file upload field. This makes libcurl load data from
the given file name when curl_easy_perform() is called. */
curl_formadd(&formpost,
&lastptr,
CURLFORM_COPYNAME, "file",
CURLFORM_FILE, util::cStringToString(sFilePath).c_str(),
CURLFORM_CONTENTTYPE, "application/octet-stream",
CURLFORM_END);


/* Fill in the filename field */
curl_formadd(&formpost,
&lastptr,
CURLFORM_COPYNAME, "filePath",
CURLFORM_COPYCONTENTS, "pcfile",
CURLFORM_END);


/* Fill in the submit field too, even if this is rarely needed */
curl_formadd(&formpost,
&lastptr,
CURLFORM_COPYNAME, "sign",
CURLFORM_COPYCONTENTS, "36023db76acfe3b8e937fde554873a59",
CURLFORM_END);


curl = curl_easy_init();
multi_handle = curl_multi_init();


/* initalize custom header list (stating that Expect: 100-continue is not
wanted */
headerlist = curl_slist_append(headerlist, buf);
if (curl && multi_handle) {


/* what URL that receives this POST */
curl_easy_setopt(curl, CURLOPT_URL, "http://192.168.10.242:7072/uploadServer/zmbb/api/upload");
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);


curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);
curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);


curl_multi_add_handle(multi_handle, curl);


curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, FileTransferModule_Impl::writeData);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, &strJosn);


res = curl_multi_perform(multi_handle, &still_running);


do {
struct timeval timeout;
int rc; /* select() return code */


fd_set fdread;
fd_set fdwrite;
fd_set fdexcep;
int maxfd = -1;


long curl_timeo = -1;


FD_ZERO(&fdread);
FD_ZERO(&fdwrite);
FD_ZERO(&fdexcep);


/* set a suitable timeout to play around with */
timeout.tv_sec = 1;
timeout.tv_usec = 0;


curl_multi_timeout(multi_handle, &curl_timeo);
if (curl_timeo >= 0) {
timeout.tv_sec = curl_timeo / 1000;
if (timeout.tv_sec > 1)
timeout.tv_sec = 1;
else
timeout.tv_usec = (curl_timeo % 1000) * 1000;
}


/* get file descriptors from the transfers */
curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd);


/* In a real-world program you OF COURSE check the return code of the
function calls.  On success, the value of maxfd is guaranteed to be
greater or equal than -1.  We call select(maxfd + 1, ...), specially in
case of (maxfd == -1), we call select(0, ...), which is basically equal
to sleep. */


rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout);


switch (rc) {
case -1:
/* select error */
break;
case 0:
default:
/* timeout or readable/writable sockets */
printf("perform!\n");
curl_multi_perform(multi_handle, &still_running);
printf("running: %d!\n", still_running);
break;
}
} while (still_running);


curl_multi_cleanup(multi_handle);


/* always cleanup */
curl_easy_cleanup(curl);


/* then cleanup the formpost chain */
curl_formfree(formpost);


/* free slist */
curl_slist_free_all(headerlist);
}


return TRUE;
}