1/*
2 * Copyright (c) 2015 Stephan Holljes
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to deal
6 * in the Software without restriction, including without limitation the rights
7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8 * copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
20 * THE SOFTWARE.
21 */
22
23/**
24 * @file
25 * libavformat multi-client network API usage example.
26 *
27 * @example http_multiclient.c
28 * This example will serve a file without decoding or demuxing it over http.
29 * Multiple clients can connect and will receive the same file.
30 */
31
32#include <libavformat/avformat.h>
33#include <libavutil/opt.h>
34#include <unistd.h>
35
36static void process_client(AVIOContext *client, const char *in_uri)
37{
38    AVIOContext *input = NULL;
39    uint8_t buf[1024];
40    int ret, n, reply_code;
41    uint8_t *resource = NULL;
42    while ((ret = avio_handshake(client)) > 0) {
43        av_opt_get(client, "resource", AV_OPT_SEARCH_CHILDREN, &resource);
44        // check for strlen(resource) is necessary, because av_opt_get()
45        // may return empty string.
46        if (resource && strlen(resource))
47            break;
48        av_freep(&resource);
49    }
50    if (ret < 0)
51        goto end;
52    av_log(client, AV_LOG_TRACE, "resource=%p\n", resource);
53    if (resource && resource[0] == '/' && !strcmp((resource + 1), in_uri)) {
54        reply_code = 200;
55    } else {
56        reply_code = AVERROR_HTTP_NOT_FOUND;
57    }
58    if ((ret = av_opt_set_int(client, "reply_code", reply_code, AV_OPT_SEARCH_CHILDREN)) < 0) {
59        av_log(client, AV_LOG_ERROR, "Failed to set reply_code: %s.\n", av_err2str(ret));
60        goto end;
61    }
62    av_log(client, AV_LOG_TRACE, "Set reply code to %d\n", reply_code);
63
64    while ((ret = avio_handshake(client)) > 0);
65
66    if (ret < 0)
67        goto end;
68
69    fprintf(stderr, "Handshake performed.\n");
70    if (reply_code != 200)
71        goto end;
72    fprintf(stderr, "Opening input file.\n");
73    if ((ret = avio_open2(&input, in_uri, AVIO_FLAG_READ, NULL, NULL)) < 0) {
74        av_log(input, AV_LOG_ERROR, "Failed to open input: %s: %s.\n", in_uri,
75               av_err2str(ret));
76        goto end;
77    }
78    for(;;) {
79        n = avio_read(input, buf, sizeof(buf));
80        if (n < 0) {
81            if (n == AVERROR_EOF)
82                break;
83            av_log(input, AV_LOG_ERROR, "Error reading from input: %s.\n",
84                   av_err2str(n));
85            break;
86        }
87        avio_write(client, buf, n);
88        avio_flush(client);
89    }
90end:
91    fprintf(stderr, "Flushing client\n");
92    avio_flush(client);
93    fprintf(stderr, "Closing client\n");
94    avio_close(client);
95    fprintf(stderr, "Closing input\n");
96    avio_close(input);
97    av_freep(&resource);
98}
99
100int main(int argc, char **argv)
101{
102    AVDictionary *options = NULL;
103    AVIOContext *client = NULL, *server = NULL;
104    const char *in_uri, *out_uri;
105    int ret, pid;
106    av_log_set_level(AV_LOG_TRACE);
107    if (argc < 3) {
108        printf("usage: %s input http://hostname[:port]\n"
109               "API example program to serve http to multiple clients.\n"
110               "\n", argv[0]);
111        return 1;
112    }
113
114    in_uri = argv[1];
115    out_uri = argv[2];
116
117    avformat_network_init();
118
119    if ((ret = av_dict_set(&options, "listen", "2", 0)) < 0) {
120        fprintf(stderr, "Failed to set listen mode for server: %s\n", av_err2str(ret));
121        return ret;
122    }
123    if ((ret = avio_open2(&server, out_uri, AVIO_FLAG_WRITE, NULL, &options)) < 0) {
124        fprintf(stderr, "Failed to open server: %s\n", av_err2str(ret));
125        return ret;
126    }
127    fprintf(stderr, "Entering main loop.\n");
128    for(;;) {
129        if ((ret = avio_accept(server, &client)) < 0)
130            goto end;
131        fprintf(stderr, "Accepted client, forking process.\n");
132        // XXX: Since we don't reap our children and don't ignore signals
133        //      this produces zombie processes.
134        pid = fork();
135        if (pid < 0) {
136            perror("Fork failed");
137            ret = AVERROR(errno);
138            goto end;
139        }
140        if (pid == 0) {
141            fprintf(stderr, "In child.\n");
142            process_client(client, in_uri);
143            avio_close(server);
144            exit(0);
145        }
146        if (pid > 0)
147            avio_close(client);
148    }
149end:
150    avio_close(server);
151    if (ret < 0 && ret != AVERROR_EOF) {
152        fprintf(stderr, "Some errors occurred: %s\n", av_err2str(ret));
153        return 1;
154    }
155    return 0;
156}
157