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 
process_client(AVIOContext * client,const char * in_uri)36 static 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     }
90 end:
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 
main(int argc,char ** argv)100 int 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     }
149 end:
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