源碼 頭文件??sdf_exception.h

#pragma once#include <exception> #include <string>namespace sdf {namespace common{using sdf_error_code_t = uint32_t;class SdfException : std::exception{public:explicit SdfException(sdf_error_code_t errorCode) : error_code(error_code){};SdfException(sdf_error_code_t errorCode,std::string error_message){}SdfException(sdf_error_code_t x,sdf_error_code_t y,sdf_error_code_t z):error_code(pack211(x,y,z)){}SdfException(sdf_error_code_t x,sdf_error_code_t y,sdf_error_code_t z,std::string error_message){}const char *what() const noexcept override;sdf_error_code_t get_error_code() const{return error_code;}public:static sdf_error_code_t pack211(sdf_error_code_t x,sdf_error_code_t y,sdf_error_code_t z){return x << 16U | y << 8U | z; //Appending u to any integral constant makes the compiler interpret it as unsigned.}private:sdf_error_code_t error_code;std::string error_message;bool error_message_packed = false;//< flag for lazy packing error message};} }

學習

• SdfException(sdf_error_code_t error_code) : error_code(error_code) {}這個是?C++ 類構造函數初始化列表?參考
• const char * 、char const *、 char * const 三者的區別??參考鏈接??參考鏈接
• const char *what() const ? ???參考鏈接
• noexcept override;? ?參考鏈接??參考鏈接?參考鏈接?參考鏈接

源文件??sdf_exception.cpp

#include "sdf_exception.h"#include "logging.h"namespace sdf { namespace common {std::string pack_error_message(sdf_error_code_t error_code,const std::string &error_message) {char buffer[1024];auto length =std::snprintf(buffer, sizeof(buffer), "sdf exception: [0x%08x] %s\n",error_code, error_message.c_str());if (length < 0 || length >= static_cast<int>(sizeof(buffer))) {log_fatal("Unexpected error message length: %s", length);}return buffer; }SdfException::SdfException(sdf_error_code_t error_code,std::string error_message): error_code(error_code), error_message(std::move(error_message)) {}SdfException::SdfException(sdf_error_code_t x, sdf_error_code_t y,sdf_error_code_t z, std::string error_message): error_code(pack211(x, y, z)), error_message(std::move(error_message)) {}const char *SdfException::what() const noexcept {if (!error_message_packed) {const_cast<bool &>(error_message_packed) = true;const_cast<std::string &>(error_message) =pack_error_message(error_code, error_message);}return error_message.c_str(); }} // namespace common } // namespace sdf

學習

• snprintf()?參考鏈接
• 淺析c＋＋中的類型轉換--static_cast??參考鏈接
• std::move?參考鏈接

代碼調用

代碼層次結構

所需要的配套文件

?logging.h

#pragma oncenamespace sdf {namespace common {enum LogLevel {SDF_LOG_DEBUG,SDF_LOG_INFO,SDF_LOG_WARN,SDF_LOG_ERROR,SDF_LOG_FATAL,SDF_LOG_IMPORTANT_INFO};void set_logging_level(LogLevel level);#define LOGGER_DECLARATION(level) void log_##level(const char *format, ...);LOGGER_DECLARATION(debug)LOGGER_DECLARATION(info)LOGGER_DECLARATION(warn)LOGGER_DECLARATION(error)LOGGER_DECLARATION(fatal)LOGGER_DECLARATION(important)#undef LOGGER_DECLARATION} // namespace common } // namespace sdf

logging.cpp

#include "logging.h" //#include "sdf_config.h"#include <cstdarg> #include <cstdio> #include <ctime> #include <mutex>#ifdef ENABLE_SYSLOG #include <syslog.h> #endifnamespace sdf {namespace common {const char *get_current_time() {static char buffer[80];time_t raw_time;std::time(&raw_time);std::strftime(buffer, sizeof(buffer), "%Y-%m-%d %H:%M:%S",localtime(&raw_time));return buffer;}class Logger {public:static inline void set_logging_level(LogLevel level) {default_logging_level = level;}#ifndef ENABLE_SYSLOGstatic void vlog(LogLevel level, const char *format, va_list ap) {if (level < Logger::default_logging_level) {return;}auto endpoint = stdout;if (level == SDF_LOG_ERROR || level == SDF_LOG_FATAL) {endpoint = stderr;}const char *level_info = nullptr;switch (level) {case SDF_LOG_DEBUG:level_info = "DEBUG";break;case SDF_LOG_INFO:case SDF_LOG_IMPORTANT_INFO:level_info = "INFO";break;case SDF_LOG_WARN:level_info = "WARN";break;case SDF_LOG_ERROR:level_info = "ERROR";break;case SDF_LOG_FATAL:level_info = "FATAL";break;default:break;}std::lock_guard<std::mutex> lock(log_mutex);::fprintf(endpoint, "[%s][%s] ", get_current_time(), level_info);::vfprintf(endpoint, format, ap);::fprintf(endpoint, "\n");if (level == SDF_LOG_FATAL) {::abort();}}#elsestatic void vlog(LogLevel level, const char *format, va_list ap) {if (level < Logger::default_logging_level) {return;}int syslog_level = 0;switch (level) {case SDF_LOG_DEBUG:syslog_level = LOG_DEBUG;break;case SDF_LOG_INFO:syslog_level = LOG_INFO;break;case SDF_LOG_IMPORTANT_INFO:syslog_level = LOG_NOTICE;break;case SDF_LOG_WARN:syslog_level = LOG_WARNING;break;case SDF_LOG_ERROR:syslog_level = LOG_ERR;break;case SDF_LOG_FATAL:syslog_level = LOG_CRIT;break;default:break;}// std::lock_guard<std::mutex> lock(log_mutex);vsyslog(syslog_level, format, ap);if (level == SDF_LOG_FATAL) {::abort();}}#endifstatic inline void log(LogLevel level, const char *format, ...) {va_list ap;va_start(ap, format);vlog(level, format, ap);va_end(ap);}private:static LogLevel default_logging_level;static std::mutex log_mutex;};LogLevel Logger::default_logging_level = LogLevel::SDF_LOG_INFO;std::mutex Logger::log_mutex;void set_logging_level(LogLevel level) { Logger::set_logging_level(level); }#define LOGGER_DEFINITION(level, level_tag) \void log_##level(const char *format, ...) { \va_list ap; \va_start(ap, format); \Logger::vlog(level_tag, format, ap); \va_end(ap); \}LOGGER_DEFINITION(debug, SDF_LOG_DEBUG)LOGGER_DEFINITION(info, SDF_LOG_INFO)LOGGER_DEFINITION(warn, SDF_LOG_WARN)LOGGER_DEFINITION(error, SDF_LOG_ERROR)LOGGER_DEFINITION(fatal, SDF_LOG_FATAL)LOGGER_DEFINITION(important, SDF_LOG_IMPORTANT_INFO)#undef LOGGER_DEFINITION} // namespace common } // namespace sdf

?random_generator.cpp

#include "random_generator.h"#include "../common/sdf_exception.h"#include <string> #include <iostream>std::string::size_type sdf::sys::GenerateRandom::NDSKeyStore_Common_GenerateRandom( size_t uiLength){std::cout << uiLength << std::endl;try {if(uiLength != 1024) // throw common::SdfException(-1);throw common::SdfException(45,"There is an error in the program, please solve it immediately!!"); // throw common::SdfException(1,2,3); // throw common::SdfException(1,2,3,"There is an error in the program, please solve it immediately!");} catch (common::SdfException& e) {// std::cerr<<"ERROR CODE:"<< e.get_error_code() << std::endl;std::cerr << e.what() << std::endl;}}

random_generator.h

#pragma once#include <cstddef> #include <string>namespace sdf {namespace sys{class GenerateRandom {public:explicit GenerateRandom() = default;virtual ~GenerateRandom() = default;static std::string::size_type NDSKeyStore_Common_GenerateRandom(size_t uiLength);};}// namespace sys }// namespace sdf

main函數調用

#include <iostream> #include <sstream>#include "../src/algorithm/random/random_generator.h" #include "../src/algorithm/common/StringBuffer.h"#define BUF_SIZE 1024 int main(){sdf::sys::GenerateRandom::NDSKeyStore_Common_GenerateRandom(1026);return 0;}

注意事項：

• catch不一定需要緊緊跟著try

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