libcurl example – http2-upload.c
Mục lục bài viết
http2-upload.c
/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) Daniel Stenberg, <[email protected]>, 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. * * SPDX-License-Identifier: curl * ***************************************************************************//* <DESC> * Multiplexed HTTP/2 uploads over a single connection * </DESC> */#include <stdio.h>#include <stdlib.h>#include <string.h>#include <fcntl.h>#include <sys/stat.h>#include <errno.h> /* somewhat unix-specific */#include <sys/time.h>#include <unistd.h> /* curl stuff */#include <curl/curl.h>#include <curl/mprintf.h> #ifndef CURLPIPE_MULTIPLEX/* This little trick will just make sure that we do not enable pipelining for libcurls old enough to not have this symbol. It is _not_ defined to zero in a recent libcurl header. */#define CURLPIPE_MULTIPLEX 0#endif #define NUM_HANDLES 1000 struct input { FILE *in; size_t bytes_read; /* count up */ CURL *hnd; int num;}; staticvoid dump(const char *text, int num, unsigned char *ptr, size_t size, char nohex){ size_t i; size_t c; unsigned int width = 0x10; if(nohex) /* without the hex output, we can fit more on screen */ width = 0x40; fprintf(stderr, "%d %s, %lu bytes (0x%lx)\n", num, text, (unsigned long)size, (unsigned long)size); for(i = 0; i<size; i += width) { fprintf(stderr, "%4.4lx: ", (unsigned long)i); if(!nohex) { /* hex not disabled, show it */ for(c = 0; c < width; c++) if(i + c < size) fprintf(stderr, "%02x ", ptr[i + c]); else fputs(" ", stderr); } for(c = 0; (c < width) && (i + c < size); c++) { /* check for 0D0A; if found, skip past and start a new line of output */ if(nohex && (i + c + 1 < size) && ptr[i + c] == 0x0D && ptr[i + c + 1] == 0x0A) { i += (c + 2 - width); break; } fprintf(stderr, "%c", (ptr[i + c] >= 0x20) && (ptr[i + c]<0x80)?ptr[i + c]:'.'); /* check again for 0D0A, to avoid an extra \n if it's at width */ if(nohex && (i + c + 2 < size) && ptr[i + c + 1] == 0x0D && ptr[i + c + 2] == 0x0A) { i += (c + 3 - width); break; } } fputc('\n', stderr); /* newline */ }} staticint my_trace(CURL *handle, curl_infotype type, char *data, size_t size, void *userp){ char timebuf[60]; const char *text; struct input *i = (struct input *)userp; int num = i->num; static time_t epoch_offset; static int known_offset; struct timeval tv; time_t secs; struct tm *now; (void)handle; /* prevent compiler warning */ gettimeofday(&tv, NULL); if(!known_offset) { epoch_offset = time(NULL) - tv.tv_sec; known_offset = 1; } secs = epoch_offset + tv.tv_sec; now = localtime(&secs); /* not thread safe but we do not care */ curl_msnprintf(timebuf, sizeof(timebuf), "%02d:%02d:%02d.%06ld", now->tm_hour, now->tm_min, now->tm_sec, (long)tv.tv_usec); switch(type) { case CURLINFO_TEXT: fprintf(stderr, "%s [%d] Info: %s", timebuf, num, data); /* FALLTHROUGH */ default: /* in case a new one is introduced to shock us */ return 0; case CURLINFO_HEADER_OUT: text = "=> Send header"; break; case CURLINFO_DATA_OUT: text = "=> Send data"; break; case CURLINFO_SSL_DATA_OUT: text = "=> Send SSL data"; break; case CURLINFO_HEADER_IN: text = "<= Recv header"; break; case CURLINFO_DATA_IN: text = "<= Recv data"; break; case CURLINFO_SSL_DATA_IN: text = "<= Recv SSL data"; break; } dump(text, num, (unsigned char *)data, size, 1); return 0;} static size_t read_callback(char *ptr, size_t size, size_t nmemb, void *userp){ struct input *i = userp; size_t retcode = fread(ptr, size, nmemb, i->in); i->bytes_read += retcode; return retcode;} static void setup(struct input *i, int num, const char *upload){ FILE *out; char url[256]; char filename[128]; struct stat file_info; curl_off_t uploadsize; CURL *hnd; hnd = i->hnd = curl_easy_init(); i->num = num; curl_msnprintf(filename, 128, "dl-%d", num); out = fopen(filename, "wb"); if(!out) { fprintf(stderr, "error: could not open file %s for writing: %s\n", upload, strerror(errno)); exit(1); } curl_msnprintf(url, 256, "https://localhost:8443/upload-%d", num); /* get the file size of the local file */ if(stat(upload, &file_info)) { fprintf(stderr, "error: could not stat file %s: %s\n", upload, strerror(errno)); exit(1); } uploadsize = file_info.st_size; i->in = fopen(upload, "rb"); if(!i->in) { fprintf(stderr, "error: could not open file %s for reading: %s\n", upload, strerror(errno)); exit(1); } /* write to this file */ curl_easy_setopt(hnd, CURLOPT_WRITEDATA, out); /* we want to use our own read function */ curl_easy_setopt(hnd, CURLOPT_READFUNCTION, read_callback); /* read from this file */ curl_easy_setopt(hnd, CURLOPT_READDATA, i); /* provide the size of the upload */ curl_easy_setopt(hnd, CURLOPT_INFILESIZE_LARGE, uploadsize); /* send in the URL to store the upload as */ curl_easy_setopt(hnd, CURLOPT_URL, url); /* upload please */ curl_easy_setopt(hnd, CURLOPT_UPLOAD, 1L); /* please be verbose */ curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L); curl_easy_setopt(hnd, CURLOPT_DEBUGFUNCTION, my_trace); curl_easy_setopt(hnd, CURLOPT_DEBUGDATA, i); /* 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); #if (CURLPIPE_MULTIPLEX > 0) /* wait for pipe connection to confirm */ curl_easy_setopt(hnd, CURLOPT_PIPEWAIT, 1L);#endif} /* * Upload all files over HTTP/2, using the same physical connection! */int main(int argc, char **argv){ struct input trans[NUM_HANDLES]; CURLM *multi_handle; int i; int still_running = 0; /* keep number of running handles */ const char *filename = "index.html"; int num_transfers; if(argc > 1) { /* if given a number, do that many transfers */ num_transfers = atoi(argv[1]); if(!num_transfers || (num_transfers > NUM_HANDLES)) num_transfers = 3; /* a suitable low default */ if(argc > 2) /* if given a file name, upload this! */ filename = argv[2]; } else num_transfers = 3; /* init a multi stack */ multi_handle = curl_multi_init(); for(i = 0; i<num_transfers; i++) { setup(&trans[i], i, filename); /* add the individual transfer */ curl_multi_add_handle(multi_handle, trans[i].hnd); } curl_multi_setopt(multi_handle, CURLMOPT_PIPELINING, CURLPIPE_MULTIPLEX); /* We do HTTP/2 so let's stick to one connection per host */ curl_multi_setopt(multi_handle, CURLMOPT_MAX_HOST_CONNECTIONS, 1L); do { CURLMcode mc = curl_multi_perform(multi_handle, &still_running); if(still_running) /* wait for activity, timeout or "nothing" */ mc = curl_multi_poll(multi_handle, NULL, 0, 1000, NULL); if(mc) break; } while(still_running); curl_multi_cleanup(multi_handle); for(i = 0; i<num_transfers; i++) { curl_multi_remove_handle(multi_handle, trans[i].hnd); curl_easy_cleanup(trans[i].hnd); } return 0;}
Notice
simplified and ignores return
codes and error checks to a large extent. We do this to highlight the libcurl
function calls and related options and reduce unrelated code.
This source code example isand ignores return codes and error checks to a large extent. We do this to highlight the libcurl function calls and related options and reduce unrelated code.
A real-world application will of course properly check every return value and
exit correctly at the first serious error.
