curl/docs/examples/multi-app.c

146 строки
4.0 KiB
C

/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
*
* This is an example application source code using the multi interface.
*/
#include <stdio.h>
#include <string.h>
/* somewhat unix-specific */
#include <sys/time.h>
#include <unistd.h>
/* curl stuff */
#include <curl/curl.h>
/*
* Download a HTTP file and upload an FTP file simultaneously.
*/
#define HANDLECOUNT 2 /* Number of simultaneous transfers */
#define HTTP_HANDLE 0 /* Index for the HTTP transfer */
#define FTP_HANDLE 1 /* Index for the FTP transfer */
int main(int argc, char **argv)
{
CURL *handles[HANDLECOUNT];
CURLM *multi_handle;
int still_running; /* keep number of running handles */
int i;
CURLMsg *msg; /* for picking up messages with the transfer status */
int msgs_left; /* how many messages are left */
/* Allocate one CURL handle per transfer */
for (i=0; i<HANDLECOUNT; i++)
handles[i] = curl_easy_init();
/* set the options (I left out a few, you'll get the point anyway) */
curl_easy_setopt(handles[HTTP_HANDLE], CURLOPT_URL, "http://example.com");
curl_easy_setopt(handles[FTP_HANDLE], CURLOPT_URL, "ftp://example.com");
curl_easy_setopt(handles[FTP_HANDLE], CURLOPT_UPLOAD, 1L);
/* init a multi stack */
multi_handle = curl_multi_init();
/* add the individual transfers */
for (i=0; i<HANDLECOUNT; i++)
curl_multi_add_handle(multi_handle, handles[i]);
/* we start some action by calling perform right away */
curl_multi_perform(multi_handle, &still_running);
while(still_running) {
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:
/* timeout, do something else */
break;
default:
/* one or more of curl's file descriptors say there's data to read
or write */
curl_multi_perform(multi_handle, &still_running);
break;
}
}
/* See how the transfers went */
while ((msg = curl_multi_info_read(multi_handle, &msgs_left))) {
if (msg->msg == CURLMSG_DONE) {
int idx, found = 0;
/* Find out which handle this message is about */
for (idx=0; idx<HANDLECOUNT; idx++) {
found = (msg->easy_handle == handles[idx]);
if(found)
break;
}
switch (idx) {
case HTTP_HANDLE:
printf("HTTP transfer completed with status %d\n", msg->data.result);
break;
case FTP_HANDLE:
printf("FTP transfer completed with status %d\n", msg->data.result);
break;
}
}
}
curl_multi_cleanup(multi_handle);
/* Free the CURL handles */
for (i=0; i<HANDLECOUNT; i++)
curl_easy_cleanup(handles[i]);
return 0;
}