aboutsummaryrefslogtreecommitdiffstats
path: root/libavformat/rtmphttp.c
blob: fdcff50beda6ea74262651fd61f3002cb0ab4956 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
/*
 * RTMP HTTP network protocol
 * Copyright (c) 2012 Samuel Pitoiset
 *
 * This file is part of Libav.
 *
 * Libav 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.
 *
 * Libav 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 Libav; 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 "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
} 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;

    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 ((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;
        }
    } 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,
};