ftp-wildcard.c
/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) 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. * * SPDX-License-Identifier: curl * ***************************************************************************/ /* <DESC> * FTP wildcard pattern matching * </DESC> */ #include <curl/curl.h> #include <stdio.h> struct callback_data { FILE *output; }; static long file_is_coming(struct curl_fileinfo *finfo, struct callback_data *data, int remains); static long file_is_downloaded(struct callback_data *data); static size_t write_it(char *buff, size_t size, size_t nmemb, void *cb_data); int main(int argc, char **argv) { /* curl easy handle */ CURL *handle; /* help data */ struct callback_data data = { 0 }; /* global initialization */ CURLcode rc = curl_global_init(CURL_GLOBAL_ALL); if(rc) return (int)rc; /* initialization of easy handle */ handle = curl_easy_init(); if(!handle) { curl_global_cleanup(); return CURLE_OUT_OF_MEMORY; } /* turn on wildcard matching */ curl_easy_setopt(handle, CURLOPT_WILDCARDMATCH, 1L); /* callback is called before download of concrete file started */ curl_easy_setopt(handle, CURLOPT_CHUNK_BGN_FUNCTION, file_is_coming); /* callback is called after data from the file have been transferred */ curl_easy_setopt(handle, CURLOPT_CHUNK_END_FUNCTION, file_is_downloaded); /* this callback writes contents into files */ curl_easy_setopt(handle, CURLOPT_WRITEFUNCTION, write_it); /* put transfer data into callbacks */ curl_easy_setopt(handle, CURLOPT_CHUNK_DATA, &data); curl_easy_setopt(handle, CURLOPT_WRITEDATA, &data); /* curl_easy_setopt(handle, CURLOPT_VERBOSE, 1L); */ /* set a URL containing wildcard pattern (only in the last part) */ if(argc == 2) curl_easy_setopt(handle, CURLOPT_URL, argv[1]); else curl_easy_setopt(handle, CURLOPT_URL, "ftp://example.com/test/*"); /* and start transfer! */ rc = curl_easy_perform(handle); curl_easy_cleanup(handle); curl_global_cleanup(); return (int)rc; } static long file_is_coming(struct curl_fileinfo *finfo, struct callback_data *data, int remains) { printf("%3d %40s %10luB ", remains, finfo->filename, (unsigned long)finfo->size); switch(finfo->filetype) { case CURLFILETYPE_DIRECTORY: printf(" DIR\n"); break; case CURLFILETYPE_FILE: printf("FILE "); break; default: printf("OTHER\n"); break; } if(finfo->filetype == CURLFILETYPE_FILE) { /* do not transfer files >= 50B */ if(finfo->size > 50) { printf("SKIPPED\n"); return CURL_CHUNK_BGN_FUNC_SKIP; } data->output = fopen(finfo->filename, "wb"); if(!data->output) { return CURL_CHUNK_BGN_FUNC_FAIL; } } return CURL_CHUNK_BGN_FUNC_OK; } static long file_is_downloaded(struct callback_data *data) { if(data->output) { printf("DOWNLOADED\n"); fclose(data->output); data->output = 0x0; } return CURL_CHUNK_END_FUNC_OK; } static size_t write_it(char *buff, size_t size, size_t nmemb, void *cb_data) { struct callback_data *data = cb_data; size_t written = 0; if(data->output) written = fwrite(buff, size, nmemb, data->output); else /* listing output */ written = fwrite(buff, size, nmemb, stdout); return written; }
Notice
This source code example is 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.
A real-world application will of course properly check every return value and exit correctly at the first serious error.