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CommonTools.h
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/* * CommonTools.h * * Created on: 2018年8月2日 * Author: didi */ #include <iostream> #include <curl/curl.h> #include "zlib.h" #include <vector> #include <string> #include <unistd.h> #include <memory.h> #include <json/json.h> #include <sstream> using namespace std; class CommonTools{ public: CommonTools(); ~CommonTools(); public: static size_t receive_data(void *contents, size_t size, size_t nmemb, void *stream); // HTTP 下载文件的回掉函数 static size_t writedata2file(void *ptr, size_t size, size_t nmemb, FILE *stream); // 文件下载接口 static int download_file(const char* url, const char outfilename[FILENAME_MAX]); // http get 请求 static CURLcode HttpGet(const std::string & strUrl, std::string & strResponse,int nTimeout); // htpp post 请求 static CURLcode HttpPost(const std::string & strUrl, std::string szJson,std::string & strResponse,int nTimeout); }
CommonTools.cpp
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#include "CommonTools.h" using namespace std; size_t CommonTools::receive_data(void *contents, size_t size, size_t nmemb, void *stream){ string *str = (string*)stream; (*str).append((char*)contents, size*nmemb); return size * nmemb; } size_t CommonTools::writedata2file(void *ptr, size_t size, size_t nmemb, FILE *stream) { size_t written = fwrite(ptr, size, nmemb, stream); return written; } int CommonTools::download_file(const char* url, const char outfilename[FILENAME_MAX]){ CURL *curl; FILE *fp; CURLcode res; /* 调用curl_global_init()初始化libcurl */ res = curl_global_init(CURL_GLOBAL_ALL); if (CURLE_OK != res) { printf("init libcurl failed."); curl_global_cleanup(); return -1; } /* 调用curl_easy_init()函数得到 easy interface型指针 */ curl = curl_easy_init(); if (curl) { fp = fopen(outfilename,"wb"); /* 调用curl_easy_setopt()设置传输选项 */ res = curl_easy_setopt(curl, CURLOPT_URL, url); if (res != CURLE_OK) { fclose(fp); curl_easy_cleanup(curl); return -1; } /* 根据curl_easy_setopt()设置的传输选项,实现回调函数以完成用户特定任务 */ res = curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CommonTools::writedata2file); if (res != CURLE_OK){ fclose(fp); curl_easy_cleanup(curl); return -1; } /* 根据curl_easy_setopt()设置的传输选项,实现回调函数以完成用户特定任务 */ res = curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp); if (res != CURLE_OK) { fclose(fp); curl_easy_cleanup(curl); return -1; } res = curl_easy_perform(curl); // 调用curl_easy_perform()函数完成传输任务 fclose(fp); /* Check for errors */ if(res != CURLE_OK){ fprintf(stderr, "curl_easy_perform() failed: %s ",curl_easy_strerror(res)); curl_easy_cleanup(curl); return -1; } /* always cleanup */ curl_easy_cleanup(curl); // 调用curl_easy_cleanup()释放内存 } curl_global_cleanup(); return 0; } CURLcode CommonTools::HttpGet(const std::string & strUrl, std::string & strResponse,int nTimeout){ CURLcode res; CURL* pCURL = curl_easy_init(); if (pCURL == NULL) { return CURLE_FAILED_INIT; } curl_easy_setopt(pCURL, CURLOPT_URL, strUrl.c_str()); //curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); curl_easy_setopt(pCURL, CURLOPT_NOSIGNAL, 1L); curl_easy_setopt(pCURL, CURLOPT_TIMEOUT, nTimeout); curl_easy_setopt(pCURL, CURLOPT_NOPROGRESS, 1L); curl_easy_setopt(pCURL, CURLOPT_WRITEFUNCTION, CommonTools::receive_data); curl_easy_setopt(pCURL, CURLOPT_WRITEDATA, (void*)&strResponse); res = curl_easy_perform(pCURL); curl_easy_cleanup(pCURL); return res; } CURLcode CommonTools::HttpPost(const std::string & strUrl, std::string szJson,std::string & strResponse,int nTimeout){ CURLcode res; char szJsonData[1024]; memset(szJsonData, 0, sizeof(szJsonData)); strcpy(szJsonData, szJson.c_str()); CURL* pCURL = curl_easy_init(); struct curl_slist* headers = NULL; if (pCURL == NULL) { return CURLE_FAILED_INIT; } CURLcode ret; ret = curl_easy_setopt(pCURL, CURLOPT_URL, strUrl.c_str()); // std::cout << ret << std::endl; ret = curl_easy_setopt(pCURL, CURLOPT_POST, 1L); headers = curl_slist_append(headers,"content-type:application/json"); ret = curl_easy_setopt(pCURL, CURLOPT_HTTPHEADER, headers); ret = curl_easy_setopt(pCURL, CURLOPT_POSTFIELDS, szJsonData); //curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); ret = curl_easy_setopt(pCURL, CURLOPT_TIMEOUT, nTimeout); ret = curl_easy_setopt(pCURL, CURLOPT_WRITEFUNCTION, CommonTools::receive_data); ret = curl_easy_setopt(pCURL, CURLOPT_WRITEDATA, (void*)&strResponse); res = curl_easy_perform(pCURL); curl_easy_cleanup(pCURL); return res; }
使用方法
Main.cpp
// get 请求 string strURL = "http://www.baidu.com"; string strResponse; CURLcode nRes = CommonTools::HttpGet(strURL, strResponse,300); size_t nSrcLength = strResponse.length(); //下载文件 string strURL = "http://www.baidu.com/aaa.dat"; char local_file[50] = {0}; sprintf(local_file,"./pb_%d_%s.dat",1,"aaaa"); int iDownlaod_Success = CommonTools::download_file(url.c_str(),local_file); if(iDownlaod_Success<0){ char download_failure_info[100] ={0}; sprintf(download_failure_info,"download file :%s ,failure,url:",local_file,url); FATAL(download_failure_info); }