DN/External/curl-8.17.0/docs/examples/websocket-updown.c

129 lines
3.7 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
/* <DESC>
* WebSocket download-only using write callback
* </DESC>
*/
#include <stdio.h>
#include <string.h>
#include <curl/curl.h>
static size_t write_cb(char *b, size_t size, size_t nitems, void *p)
{
CURL *curl = p;
size_t i;
unsigned int blen = (unsigned int)(nitems * size);
const struct curl_ws_frame *frame = curl_ws_meta(curl);
fprintf(stderr, "Type: %s\n", frame->flags & CURLWS_BINARY ?
"binary" : "text");
if(frame->flags & CURLWS_BINARY) {
fprintf(stderr, "Bytes: %u", blen);
for(i = 0; i < nitems; i++)
fprintf(stderr, "%02x ", (unsigned char)b[i]);
fprintf(stderr, "\n");
}
else
fprintf(stderr, "Text: %.*s\n", (int)blen, b);
return nitems;
}
struct read_ctx {
CURL *curl;
char buf[1024];
size_t blen;
size_t nsent;
};
static size_t read_cb(char *buf, size_t nitems, size_t buflen, void *p)
{
struct read_ctx *ctx = p;
size_t len = nitems * buflen;
size_t left = ctx->blen - ctx->nsent;
CURLcode result;
if(!ctx->nsent) {
/* On first call, set the FRAME information to be used (it defaults
* to CURLWS_BINARY otherwise). */
result = curl_ws_start_frame(ctx->curl, CURLWS_TEXT,
(curl_off_t)ctx->blen);
if(result) {
fprintf(stderr, "error starting frame: %d\n", result);
return CURL_READFUNC_ABORT;
}
}
fprintf(stderr, "read(len=%d, left=%d)\n", (int)len, (int)left);
if(left) {
if(left < len)
len = left;
memcpy(buf, ctx->buf + ctx->nsent, len);
ctx->nsent += len;
return len;
}
return 0;
}
int main(int argc, const char *argv[])
{
CURL *curl;
struct read_ctx rctx;
const char *payload = "Hello, friend!";
CURLcode res = curl_global_init(CURL_GLOBAL_ALL);
if(res)
return (int)res;
memset(&rctx, 0, sizeof(rctx));
curl = curl_easy_init();
if(curl) {
if(argc == 2)
curl_easy_setopt(curl, CURLOPT_URL, argv[1]);
else
curl_easy_setopt(curl, CURLOPT_URL, "wss://example.com");
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_cb);
curl_easy_setopt(curl, CURLOPT_WRITEDATA, curl);
curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_cb);
/* tell curl that we want to send the payload */
rctx.curl = curl;
rctx.blen = strlen(payload);
memcpy(rctx.buf, payload, rctx.blen);
curl_easy_setopt(curl, CURLOPT_READDATA, &rctx);
curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
/* Perform the request, res gets the return code */
res = curl_easy_perform(curl);
/* Check for errors */
if(res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(res));
/* always cleanup */
curl_easy_cleanup(curl);
}
curl_global_cleanup();
return (int)res;
}