/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at https://curl.se/docs/copyright.html. * * You may opt to use, copy, modify, merge, publish, distribute and/or sell * copies of the Software, and permit persons to whom the Software is * furnished to do so, under the terms of the COPYING file. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ***************************************************************************/ /* <DESC> * HTTP/2 server push. Receive all data in memory. * </DESC> */ #include <stdio.h> #include <stdlib.h> #include <string.h> /* somewhat unix-specific */ #include <sys/time.h> #include <unistd.h> /* curl stuff */ #include <curl/curl.h> struct Memory { char *memory; size_t size; }; static size_t write_cb(void *contents, size_t size, size_t nmemb, void *userp) { size_t realsize = size * nmemb; struct Memory *mem = (struct Memory *)userp; char *ptr = realloc(mem->memory, mem->size + realsize + 1); if(!ptr) { /* out of memory! */ printf("not enough memory (realloc returned NULL)\n"); return 0; } mem->memory = ptr; memcpy(&(mem->memory[mem->size]), contents, realsize); mem->size += realsize; mem->memory[mem->size] = 0; return realsize; } #define MAX_FILES 10 static struct Memory files[MAX_FILES]; static int pushindex = 1; static void init_memory(struct Memory *chunk) { chunk->memory = malloc(1); /* grown as needed with realloc */ chunk->size = 0; /* no data at this point */ } static void setup(CURL *hnd) { /* set the same URL */ curl_easy_setopt(hnd, CURLOPT_URL, "https://localhost:8443/index.html"); /* HTTP/2 please */ curl_easy_setopt(hnd, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2_0); /* we use a self-signed test server, skip verification during debugging */ curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYPEER, 0L); curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYHOST, 0L); /* write data to a struct */ curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION, write_cb); init_memory(&files[0]); curl_easy_setopt(hnd, CURLOPT_WRITEDATA, &files[0]); /* wait for pipe connection to confirm */ curl_easy_setopt(hnd, CURLOPT_PIPEWAIT, 1L); } /* called when there's an incoming push */ static int server_push_callback(CURL *parent, CURL *easy, size_t num_headers, struct curl_pushheaders *headers, void *userp) { char *headp; int *transfers = (int *)userp; (void)parent; /* we have no use for this */ (void)num_headers; /* unused */ if(pushindex == MAX_FILES) /* can't fit anymore */ return CURL_PUSH_DENY; /* write to this buffer */ init_memory(&files[pushindex]); curl_easy_setopt(easy, CURLOPT_WRITEDATA, &files[pushindex]); pushindex++; headp = curl_pushheader_byname(headers, ":path"); if(headp) fprintf(stderr, "* Pushed :path '%s'\n", headp /* skip :path + colon */); (*transfers)++; /* one more */ return CURL_PUSH_OK; } /* * Download a file over HTTP/2, take care of server push. */ int main(void) { CURL *easy; CURLM *multi; int still_running; /* keep number of running handles */ int transfers = 1; /* we start with one */ int i; struct CURLMsg *m; /* init a multi stack */ multi = curl_multi_init(); easy = curl_easy_init(); /* set options */ setup(easy); /* add the easy transfer */ curl_multi_add_handle(multi, easy); curl_multi_setopt(multi, CURLMOPT_PIPELINING, CURLPIPE_MULTIPLEX); curl_multi_setopt(multi, CURLMOPT_PUSHFUNCTION, server_push_callback); curl_multi_setopt(multi, CURLMOPT_PUSHDATA, &transfers); while(transfers) { int rc; CURLMcode mcode = curl_multi_perform(multi, &still_running); if(mcode) break; mcode = curl_multi_wait(multi, NULL, 0, 1000, &rc); if(mcode) break; /* * When doing server push, libcurl itself created and added one or more * easy handles but *we* need to clean them up when they are done. */ do { int msgq = 0; m = curl_multi_info_read(multi, &msgq); if(m && (m->msg == CURLMSG_DONE)) { CURL *e = m->easy_handle; transfers--; curl_multi_remove_handle(multi, e); curl_easy_cleanup(e); } } while(m); } curl_multi_cleanup(multi); /* 'pushindex' is now the number of received transfers */ for(i = 0; i < pushindex; i++) { /* do something fun with the data, and then free it when done */ free(files[i].memory); } return 0; }