ffmpeg/libavformat/rtmphttp.c

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/*
* RTMP HTTP network protocol
* Copyright (c) 2012 Samuel Pitoiset
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* RTMP HTTP protocol
*/
#include "libavutil/avstring.h"
#include "libavutil/intfloat.h"
#include "libavutil/opt.h"
#include "libavutil/time.h"
#include "internal.h"
#include "http.h"
#define RTMPT_DEFAULT_PORT 80
/* protocol handler context */
typedef struct RTMP_HTTPContext {
URLContext *stream; ///< HTTP stream
char host[256]; ///< hostname of the server
int port; ///< port to connect (default is 80)
char client_id[64]; ///< client ID used for all requests except the first one
int seq; ///< sequence ID used for all requests
uint8_t *out_data; ///< output buffer
int out_size; ///< current output buffer size
int out_capacity; ///< current output buffer capacity
int initialized; ///< flag indicating when the http context is initialized
int finishing; ///< flag indicating when the client closes the connection
int nb_bytes_read; ///< number of bytes read since the last request
} RTMP_HTTPContext;
static int rtmp_http_send_cmd(URLContext *h, const char *cmd)
{
RTMP_HTTPContext *rt = h->priv_data;
char uri[2048];
uint8_t c;
int ret;
ff_url_join(uri, sizeof(uri), "http", NULL, rt->host, rt->port,
"/%s/%s/%d", cmd, rt->client_id, rt->seq++);
av_opt_set_bin(rt->stream->priv_data, "post_data", rt->out_data,
rt->out_size, 0);
/* send a new request to the server */
if ((ret = ff_http_do_new_request(rt->stream, uri)) < 0)
return ret;
/* re-init output buffer */
rt->out_size = 0;
/* read the first byte which contains the polling interval */
if ((ret = ffurl_read(rt->stream, &c, 1)) < 0)
return ret;
/* re-init the number of bytes read */
rt->nb_bytes_read = 0;
return ret;
}
static int rtmp_http_write(URLContext *h, const uint8_t *buf, int size)
{
RTMP_HTTPContext *rt = h->priv_data;
void *ptr;
if (rt->out_size + size > rt->out_capacity) {
rt->out_capacity = (rt->out_size + size) * 2;
ptr = av_realloc(rt->out_data, rt->out_capacity);
if (!ptr)
return AVERROR(ENOMEM);
rt->out_data = ptr;
}
memcpy(rt->out_data + rt->out_size, buf, size);
rt->out_size += size;
return size;
}
static int rtmp_http_read(URLContext *h, uint8_t *buf, int size)
{
RTMP_HTTPContext *rt = h->priv_data;
int ret, off = 0;
/* try to read at least 1 byte of data */
do {
ret = ffurl_read(rt->stream, buf + off, size);
if (ret < 0 && ret != AVERROR_EOF)
return ret;
if (ret == AVERROR_EOF) {
if (rt->finishing) {
/* Do not send new requests when the client wants to
* close the connection. */
return AVERROR(EAGAIN);
}
/* When the client has reached end of file for the last request,
* we have to send a new request if we have buffered data.
* Otherwise, we have to send an idle POST. */
if (rt->out_size > 0) {
if ((ret = rtmp_http_send_cmd(h, "send")) < 0)
return ret;
} else {
if (rt->nb_bytes_read == 0) {
/* Wait 50ms before retrying to read a server reply in
* order to reduce the number of idle requets. */
av_usleep(50000);
}
if ((ret = rtmp_http_write(h, "", 1)) < 0)
return ret;
if ((ret = rtmp_http_send_cmd(h, "idle")) < 0)
return ret;
}
if (h->flags & AVIO_FLAG_NONBLOCK) {
/* no incoming data to handle in nonblocking mode */
return AVERROR(EAGAIN);
}
} else {
off += ret;
size -= ret;
rt->nb_bytes_read += ret;
}
} while (off <= 0);
return off;
}
static int rtmp_http_close(URLContext *h)
{
RTMP_HTTPContext *rt = h->priv_data;
uint8_t tmp_buf[2048];
int ret = 0;
if (rt->initialized) {
/* client wants to close the connection */
rt->finishing = 1;
do {
ret = rtmp_http_read(h, tmp_buf, sizeof(tmp_buf));
} while (ret > 0);
/* re-init output buffer before sending the close command */
rt->out_size = 0;
if ((ret = rtmp_http_write(h, "", 1)) == 1)
ret = rtmp_http_send_cmd(h, "close");
}
av_freep(&rt->out_data);
ffurl_close(rt->stream);
return ret;
}
static int rtmp_http_open(URLContext *h, const char *uri, int flags)
{
RTMP_HTTPContext *rt = h->priv_data;
char headers[1024], url[1024];
int ret, off = 0;
av_url_split(NULL, 0, NULL, 0, rt->host, sizeof(rt->host), &rt->port,
NULL, 0, uri);
if (rt->port < 0)
rt->port = RTMPT_DEFAULT_PORT;
/* This is the first request that is sent to the server in order to
* register a client on the server and start a new session. The server
* replies with a unique id (usually a number) that is used by the client
* for all future requests.
* Note: the reply doesn't contain a value for the polling interval.
* A successful connect resets the consecutive index that is used
* in the URLs. */
ff_url_join(url, sizeof(url), "http", NULL, rt->host, rt->port, "/open/1");
/* alloc the http context */
if ((ret = ffurl_alloc(&rt->stream, url, AVIO_FLAG_READ_WRITE, NULL)) < 0)
goto fail;
/* set options */
snprintf(headers, sizeof(headers),
"Cache-Control: no-cache\r\n"
"Content-type: application/x-fcs\r\n"
"User-Agent: Shockwave Flash\r\n");
av_opt_set(rt->stream->priv_data, "headers", headers, 0);
av_opt_set(rt->stream->priv_data, "multiple_requests", "1", 0);
av_opt_set_bin(rt->stream->priv_data, "post_data", "", 1, 0);
/* open the http context */
if ((ret = ffurl_connect(rt->stream, NULL)) < 0)
goto fail;
/* read the server reply which contains a unique ID */
for (;;) {
ret = ffurl_read(rt->stream, rt->client_id + off, sizeof(rt->client_id) - off);
if (ret == AVERROR_EOF)
break;
if (ret < 0)
goto fail;
off += ret;
if (off == sizeof(rt->client_id)) {
ret = AVERROR(EIO);
goto fail;
}
}
while (off > 0 && isspace(rt->client_id[off - 1]))
off--;
rt->client_id[off] = '\0';
/* http context is now initialized */
rt->initialized = 1;
return 0;
fail:
rtmp_http_close(h);
return ret;
}
URLProtocol ff_rtmphttp_protocol = {
.name = "rtmphttp",
.url_open = rtmp_http_open,
.url_read = rtmp_http_read,
.url_write = rtmp_http_write,
.url_close = rtmp_http_close,
.priv_data_size = sizeof(RTMP_HTTPContext),
.flags = URL_PROTOCOL_FLAG_NETWORK,
};