1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22 /* <DESC>
23 * HTTP/2 server push. Receive all data in memory.
24 * </DESC>
25 */
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29
30 /* somewhat unix-specific */
31 #include <sys/time.h>
32 #include <unistd.h>
33
34 /* curl stuff */
35 #include <curl/curl.h>
36
37 struct Memory {
38 char *memory;
39 size_t size;
40 };
41
42 static size_t
write_cb(void * contents,size_t size,size_t nmemb,void * userp)43 write_cb(void *contents, size_t size, size_t nmemb, void *userp)
44 {
45 size_t realsize = size * nmemb;
46 struct Memory *mem = (struct Memory *)userp;
47 char *ptr = realloc(mem->memory, mem->size + realsize + 1);
48 if(!ptr) {
49 /* out of memory! */
50 printf("not enough memory (realloc returned NULL)\n");
51 return 0;
52 }
53
54 mem->memory = ptr;
55 memcpy(&(mem->memory[mem->size]), contents, realsize);
56 mem->size += realsize;
57 mem->memory[mem->size] = 0;
58
59 return realsize;
60 }
61
62 #define MAX_FILES 10
63 static struct Memory files[MAX_FILES];
64 static int pushindex = 1;
65
init_memory(struct Memory * chunk)66 static void init_memory(struct Memory *chunk)
67 {
68 chunk->memory = malloc(1); /* grown as needed with realloc */
69 chunk->size = 0; /* no data at this point */
70 }
71
setup(CURL * hnd)72 static void setup(CURL *hnd)
73 {
74 /* set the same URL */
75 curl_easy_setopt(hnd, CURLOPT_URL, "https://localhost:8443/index.html");
76
77 /* HTTP/2 please */
78 curl_easy_setopt(hnd, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2_0);
79
80 /* we use a self-signed test server, skip verification during debugging */
81 curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYPEER, 0L);
82 curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYHOST, 0L);
83
84 /* write data to a struct */
85 curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION, write_cb);
86 init_memory(&files[0]);
87 curl_easy_setopt(hnd, CURLOPT_WRITEDATA, &files[0]);
88
89 /* wait for pipe connection to confirm */
90 curl_easy_setopt(hnd, CURLOPT_PIPEWAIT, 1L);
91 }
92
93 /* called when there's an incoming push */
server_push_callback(CURL * parent,CURL * easy,size_t num_headers,struct curl_pushheaders * headers,void * userp)94 static int server_push_callback(CURL *parent,
95 CURL *easy,
96 size_t num_headers,
97 struct curl_pushheaders *headers,
98 void *userp)
99 {
100 char *headp;
101 int *transfers = (int *)userp;
102 (void)parent; /* we have no use for this */
103 (void)num_headers; /* unused */
104
105 if(pushindex == MAX_FILES)
106 /* can't fit anymore */
107 return CURL_PUSH_DENY;
108
109 /* write to this buffer */
110 init_memory(&files[pushindex]);
111 curl_easy_setopt(easy, CURLOPT_WRITEDATA, &files[pushindex]);
112 pushindex++;
113
114 headp = curl_pushheader_byname(headers, ":path");
115 if(headp)
116 fprintf(stderr, "* Pushed :path '%s'\n", headp /* skip :path + colon */);
117
118 (*transfers)++; /* one more */
119 return CURL_PUSH_OK;
120 }
121
122
123 /*
124 * Download a file over HTTP/2, take care of server push.
125 */
main(void)126 int main(void)
127 {
128 CURL *easy;
129 CURLM *multi;
130 int still_running; /* keep number of running handles */
131 int transfers = 1; /* we start with one */
132 int i;
133 struct CURLMsg *m;
134
135 /* init a multi stack */
136 multi = curl_multi_init();
137
138 easy = curl_easy_init();
139
140 /* set options */
141 setup(easy);
142
143 /* add the easy transfer */
144 curl_multi_add_handle(multi, easy);
145
146 curl_multi_setopt(multi, CURLMOPT_PIPELINING, CURLPIPE_MULTIPLEX);
147 curl_multi_setopt(multi, CURLMOPT_PUSHFUNCTION, server_push_callback);
148 curl_multi_setopt(multi, CURLMOPT_PUSHDATA, &transfers);
149
150 while(transfers) {
151 int rc;
152 CURLMcode mcode = curl_multi_perform(multi, &still_running);
153 if(mcode)
154 break;
155
156 mcode = curl_multi_wait(multi, NULL, 0, 1000, &rc);
157 if(mcode)
158 break;
159
160
161 /*
162 * When doing server push, libcurl itself created and added one or more
163 * easy handles but *we* need to clean them up when they are done.
164 */
165 do {
166 int msgq = 0;;
167 m = curl_multi_info_read(multi, &msgq);
168 if(m && (m->msg == CURLMSG_DONE)) {
169 CURL *e = m->easy_handle;
170 transfers--;
171 curl_multi_remove_handle(multi, e);
172 curl_easy_cleanup(e);
173 }
174 } while(m);
175
176 }
177
178
179 curl_multi_cleanup(multi);
180
181 /* 'pushindex' is now the number of received transfers */
182 for(i = 0; i < pushindex; i++) {
183 /* do something fun with the data, and then free it when done */
184 free(files[i].memory);
185 }
186
187 return 0;
188 }
189