c注册cpp回调函数

在C语言中注册回调函数，函数需要使用静态函数，可使用bind和function来转换

案例一：

#include <iostream>
#include <functional>
#include <string.h>
#include "http_server.h"
#include "ret_err_code.h"
#include "log_api.h"#include "file_transfer.h"
#include "request_reprogram.h"
#include "request_progress.h"#define PORT "8089"
#define HOST_INFO "http://localhost:8089"#define FILE_TRANSFER "/path/a"
#define REQUEST_REPROGRAM "/path/b"
#define REQUEST_PROGRESS "/path/c"std::mutex HttpServer::mtx;
HttpServer *HttpServer::instance = nullptr;
std::function<int32_t(struct mg_connection *conn, void *cbdata)> EcuFileTransferHandler;
std::function<int32_t(struct mg_connection *conn, void *cbdata)> RequestReprogramHandler;
std::function<int32_t(struct mg_connection *conn, void *cbdata)> RequestProgressHandler;extern "C" {int32_t EcuFileTransferHandlerWrapper(struct mg_connection *conn, void *cbdata) {if (EcuFileTransferHandler) {return EcuFileTransferHandler(conn, cbdata);}return RET_OK;}int32_t RequestReprogramHandlerWrapper(struct mg_connection *conn, void *cbdata) {if (RequestReprogramHandler) {return RequestReprogramHandler(conn, cbdata);}return RET_OK;}int32_t RequestProgressHandlerWrapper(struct mg_connection *conn, void *cbdata) {if (RequestProgressHandler) {return RequestProgressHandler(conn, cbdata);}return RET_OK;}
}HttpServer::HttpServer()
{EcuFileTransferHandler = std::bind(&EcuFileTransfer::EcuFileTransferHandler, EcuFileTransfer::GetInstance(), std::placeholders::_1, std::placeholders::_2);RequestReprogramHandler = std::bind(&RequestReprogram::RequestReprogramHandler, RequestReprogram::GetInstance(), std::placeholders::_1, std::placeholders::_2);RequestProgressHandler = std::bind(&RequestProgress::RequestProgressHandler, RequestProgress::GetInstance(), std::placeholders::_1, std::placeholders::_2);
}HttpServer* HttpServer::GetInstance(void)
{if (instance == nullptr) {std::lock_guard<std::mutex> lock(mtx);if (instance == nullptr) {instance = new HttpServer;}}return instance;
}void HttpServer::DelInstance(void)
{std::lock_guard<std::mutex> lock(mtx);if (instance) {delete instance;instance = nullptr;}
}int32_t HttpServer::SetSourcePackagePath(string path)
{sourcePackagePath = path;return RET_OK;
}int32_t HttpServer::SetTargetPackagePath(string path)
{targetPackagePath = path;return RET_OK;
}static int LogMessage(const struct mg_connection *conn, const char *message)
{puts(message);return RET_OK;
}int32_t HttpServer::Init()
{EcuFileTransfer::GetInstance()->SetSourcePackagePath(sourcePackagePath);EcuFileTransfer::GetInstance()->SetTargetPackagePath(targetPackagePath);const char *options[] = {"listening_ports",PORT,"request_timeout_ms","10000","error_log_file","error.log","enable_auth_domain_check","no",0};int err = 0;/* Check if libcivetweb has been built with all required features. */mg_init_library(MG_FEATURES_DEFAULT);if (err) {LOG_ERR("Cannot start CivetWeb - inconsistent build.\n");return RET_EINVAL;}/* Callback will print error messages to console */memset(&callbacks, 0, sizeof(callbacks));callbacks.log_message = LogMessage;/* Start CivetWeb web server */ctx = mg_start(&callbacks, 0, options);if (ctx == nullptr) {LOG_ERR("Cannot start CivetWeb - mg_start failed.");return RET_EINVAL;}/* OTA-MASTER HTTP SERVER */mg_set_request_handler(ctx, FILE_TRANSFER, EcuFileTransferHandlerWrapper, 0);mg_set_request_handler(ctx, REQUEST_REPROGRAM, RequestReprogramHandlerWrapper, 0);mg_set_request_handler(ctx, REQUEST_PROGRESS, RequestProgressHandlerWrapper, 0);return RET_OK;
}int32_t HttpServer::Deinit()
{/* Stop the server */mg_stop(ctx);return RET_OK;
}

案例二：

#include <iostream>
#include <stdlib.h>
#include <string>
#include <cstring>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>
#include <functional>
#include "file_transfer.h"
#include "ret_err_code.h"
#include "cJSON.h"
#include "def_databus.h"std::mutex EcuFileTransfer::mtx;
EcuFileTransfer *EcuFileTransfer::instance = nullptr;
std::function<int32_t(const char *key, const char *filename, char *path, size_t pathlen, void *user_data)> FieldFound;
std::function<int32_t(const char *key, const char *value, size_t valuelen, void *user_data)> FieldGet;
std::function<int32_t(const char *path, long long file_size, void *user_data)> FieldStore;extern packagesListInfo ServerPackListInfo;extern "C" {int32_t FieldFoundWrapper(const char *key, const char *filename, char *path, size_t pathlen, void *user_data) {if (FieldFound) {return FieldFound(key, filename, path, pathlen, user_data);}return RET_OK;}int32_t FieldGetWrapper(const char *key, const char *value, size_t valuelen, void *user_data) {if (FieldGet) {return FieldGet(key, value, valuelen, user_data);}return RET_OK;}int32_t FieldStoreWrapper(const char *path, long long file_size, void *user_data) {if (FieldStore) {return FieldStore(path, file_size, user_data);}return RET_OK;}
}static int SendJSON(struct mg_connection *conn, cJSON *json_obj)
{char *json_str = cJSON_PrintUnformatted(json_obj);size_t json_str_len = strlen(json_str);/* Send HTTP message header */mg_send_http_ok(conn, "application/json; charset=utf-8", json_str_len);/* Send HTTP message content */mg_write(conn, json_str, json_str_len);/* Free string allocated by cJSON_Print* */cJSON_free(json_str);return (int)json_str_len;
}EcuFileTransfer::EcuFileTransfer()
{FieldFound = std::bind(&EcuFileTransfer::field_found, this, std::placeholders::_1, std::placeholders::_2, std::placeholders::_3, std::placeholders::_4, std::placeholders::_5);FieldGet = std::bind(&EcuFileTransfer::field_get, this, std::placeholders::_1, std::placeholders::_2, std::placeholders::_3, std::placeholders::_4);FieldStore = std::bind(&EcuFileTransfer::field_store, this, std::placeholders::_1, std::placeholders::_2, std::placeholders::_3);
}EcuFileTransfer* EcuFileTransfer::GetInstance(void)
{if (instance == nullptr) {std::lock_guard<std::mutex> lock(mtx);if (instance == nullptr) {instance = new EcuFileTransfer;}}return instance;
}void EcuFileTransfer::DelInstance(void)
{std::lock_guard<std::mutex> lock(mtx);if (instance) {delete instance;instance = nullptr;}
}int32_t EcuFileTransfer::SetSourcePackagePath(string path)
{sourcePackagePath = path;return RET_OK;
}int32_t EcuFileTransfer::SetTargetPackagePath(string path)
{targetPackagePath = path;return RET_OK;
}int32_t EcuFileTransfer::field_found(const char *key, const char *filename, char *path, size_t pathlen, void *user_data)
{if (strcmp(key, "file")) {return MG_FORM_FIELD_STORAGE_GET;}strcat(path, file->GetFilePath().c_str());if (access(path, 0) == -1) {int flag = mkdir(path, S_IRWXU);if (flag != 0) {std::cout << "Fail to create directory. errno " << errno << std::endl;}}strcat(path, "/");strcat(path, filename);return MG_FORM_FIELD_STORAGE_STORE;
}int32_t EcuFileTransfer::field_get(const char *key, const char *value_untruncated, size_t valuelen, void *user_data)
{/* Copy the untruncated value, so string compare functions can be used. *//* The check unit test library does not have build in memcmp functions. */if (!strcmp(key, "uuid")) {string item = string(value_untruncated, valuelen);file->SetUuid(item);} else if (!strcmp(key, "ecuId")) {string item = string(value_untruncated, valuelen);file->SetEcuId(string(item));} else if (!strcmp(key, "ecuSoftCode")) {string item = string(value_untruncated, valuelen);file->SetEcuSoftCode(string(item));} else if (!strcmp(key, "ecuSoftVer")) {string item = string(value_untruncated, valuelen);file->SetEcuSoftVer(string(item));} else if (!strcmp(key, "packageType")) {string item = string(value_untruncated, valuelen);file->SetPackageType(string(item));} else if (!strcmp(key, "fileMd5")) {string item = string(value_untruncated, valuelen);file->SetFileMd5(string(item));file->SetFilePath(string(item));} else if (!strcmp(key, "packageCount")) {string item = string(value_untruncated, valuelen);file->SetPackageCount(string(item));} else if (!strcmp(key, "packageNum")) {string item = string(value_untruncated, valuelen);file->SetPackageNum(string(item));} else if (!strcmp(key, "fileCount")) {string item = string(value_untruncated, valuelen);file->SetFileCount(string(item));} else if (!strcmp(key, "fileNum")) {string item = string(value_untruncated, valuelen);file->SetFileNum(string(item));} else {}return RET_OK;
}int32_t EcuFileTransfer::field_store(const char *path, long long file_size, void *user_data)
{file->SetStoreSuccess(true);return RET_OK;
}int32_t EcuFileTransfer::EcuFileTransferHandler(struct mg_connection *conn, void *cbdata)
{const struct mg_request_info *ri = mg_get_request_info(conn);(void)cbdata; /* currently unused */if (0 != strcmp(ri->request_method, "POST")) {/* this is not a POST request */mg_send_http_error(conn, 405, "Only post method");return 405;}if (file == nullptr) {file = new EcuFile();}struct mg_form_data_handler fdh = {FieldFoundWrapper,FieldGetWrapper,FieldStoreWrapper,NULL};fdh.user_data = nullptr;string status = "100";/* Call the form handler */int ret = mg_handle_form_request(conn, &fdh);if (ret <= 0) {std::cout << "no any elem" << std::endl;}int32_t fl = atoi(file->GetFileCount().c_str());int32_t fr = atoi(file->GetFileNum().c_str());int32_t pl = atoi(file->GetPackageCount().c_str());int32_t pr = atoi(file->GetPackageNum().c_str());if (fl == fr) {string cmd = "cd " + file->GetFilePath() +" &&" + " cat * > update.zip" +" && mkdir -p " + targetPackagePath +" && unzip -o update.zip -d " + targetPackagePath +" && rm update.zip" +" && cd .." +" && rm -r " + file->GetFilePath();FILE *fp = popen(cmd.c_str(), "r");if(fp == NULL) {perror("popen error");}pclose(fp);if (file->GetStoreSuccess()) {bool repeat = false;size_t size = ServerPackListInfo.packInfo.size();for(size_t i = 0; i < size; i++) {string id = ServerPackListInfo.packInfo.at(i).ecuId;if (!id.compare(file->GetEcuId())) {repeat = true;}}if (!repeat) {struct packagesInfo info;info.ecuId = file->GetEcuId();info.ecuSoftCode = file->GetEcuSoftCode();info.ecuSoftVer = file->GetEcuSoftVer();info.packagePath = targetPackagePath;info.packageType = file->GetPackageType();ServerPackListInfo.packInfo.push_back(info);ServerPackListInfo.packageCount = ServerPackListInfo.packInfo.size();ServerPackListInfo.batchUpdateFlag = false;ServerPackListInfo.packlistStatus = 1;ServerPackListInfo.batchId = "0.0.0";ServerPackListInfo.CreateTime = 0;}}if (pl == pr) {status = "200";}}if (file != nullptr) {delete file;file = nullptr;}cJSON *obj = cJSON_CreateObject();if (!obj) {/* insufficient memory? */mg_send_http_error(conn, 500, "Server error");return 500;}cJSON_AddStringToObject(obj, "status", status.c_str());SendJSON(conn, obj);cJSON_Delete(obj);return 200;
}int32_t EcuFile::SetUuid(string id)
{uuid = id;return RET_OK;
}int32_t EcuFile::SetEcuId(string id)
{ecuId = id;return RET_OK;
}int32_t EcuFile::SetEcuSoftCode(string code)
{ecuSoftCode = code;return RET_OK;
}int32_t EcuFile::SetEcuSoftVer(string ver)
{ecuSoftVer = ver;return RET_OK;
}int32_t EcuFile::SetPackageType(string type)
{packageType = type;return RET_OK;
}int32_t EcuFile::SetFileMd5(string md5)
{fileMd5 = md5;return RET_OK;
}int32_t EcuFile::SetPackageCount(string cnt)
{packageCount = cnt;return RET_OK;
}int32_t EcuFile::SetPackageNum(string num)
{packageNum = num;return RET_OK;
}int32_t EcuFile::SetFileCount(string cnt)
{fileCount = cnt;return RET_OK;
}int32_t EcuFile::SetFileNum(string num)
{fileNum = num;return RET_OK;
}int32_t EcuFile::SetFilePath(string path)
{filePath = path.substr(0, 8);return RET_OK;
}int32_t EcuFile::SetStoreSuccess(bool success)
{storeSuccess = success;return RET_OK;
}string EcuFile::GetUuid()
{return uuid;
}string EcuFile::GetEcuId()
{return ecuId;
}string EcuFile::GetEcuSoftCode()
{return ecuSoftCode;
}string EcuFile::GetEcuSoftVer()
{return ecuSoftVer;
}string EcuFile::GetPackageType()
{return packageType;
}string EcuFile::GetFileMd5()
{return fileMd5;
}string EcuFile::GetPackageCount()
{return packageCount;
}string EcuFile::GetPackageNum()
{return packageNum;
}string EcuFile::GetFileCount()
{return fileCount;
}string EcuFile::GetFileNum()
{return fileNum;
}string EcuFile::GetFilePath()
{return filePath;
}bool EcuFile::GetStoreSuccess()
{return storeSuccess;
}