计算程序运行时间与内存（Windows）

像online judge，用c++调用Windows api来计算Java程序的运行时间与内存。

IDE：VS2013（VS2010对c++11支持不好，#include <future>会报错，就装了2013的）

Demo.Java：

import java.util.Scanner;

public class Demo {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int a = in.nextInt();
int b = in.nextInt();
System.out.println(a + b);
}
}

cpp：
#pragma comment(lib,"Psapi.lib")

#include <iostream>
#include <time.h>
#include <windows.h>
#include <psapi.h>
#include <tlhelp32.h>
#include <future>
using namespace std;

int getExitCode(HANDLE& hProcess) {
DWORD exitCode = 0;
GetExitCodeProcess(hProcess, &exitCode);
return exitCode;
}

bool killProcess(PROCESS_INFORMATION& processInfo) {
DWORD processId = processInfo.dwProcessId;
PROCESSENTRY32 processEntry = { 0 };
processEntry.dwSize = sizeof(PROCESSENTRY32);
//给系统内的所有进程拍一个快照
HANDLE handleSnap = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);

//遍历每个正在运行的进程
if (Process32First(handleSnap, &processEntry)) {
BOOL isContinue = TRUE;

//终止子进程
do {
if (processEntry.th32ParentProcessID == processId) {
HANDLE hChildProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, processEntry.th32ProcessID);
if (hChildProcess) {
TerminateProcess(hChildProcess, 1);
CloseHandle(hChildProcess);
}
}
isContinue = Process32Next(handleSnap, &processEntry);
} while (isContinue);

HANDLE hBaseProcess = OpenProcess(PROCESS_ALL_ACCESS, FALSE, processId);
if (hBaseProcess) {
TerminateProcess(hBaseProcess, 1);
CloseHandle(hBaseProcess);
}
}
if (getExitCode(processInfo.hProcess) == STILL_ACTIVE) {
return false;
}
return true;
}

int getCurrentMemoryUsage(HANDLE& hProcess){
int currentMemoryUsage = 0;
PROCESS_MEMORY_COUNTERS pmc;

if (!GetProcessMemoryInfo(hProcess, &pmc, sizeof(pmc))) {
return 0;
}
currentMemoryUsage = pmc.PeakWorkingSetSize >> 10;

if (currentMemoryUsage < 0) {
currentMemoryUsage = INT_MAX >> 10;
}
return currentMemoryUsage;
}

int getMaxMemoryUsage(PROCESS_INFORMATION& processInfo, int memoryLimit) {
int maxMemoryUsage = 0;
int currentMemoryUsage = 0;
do {
currentMemoryUsage = getCurrentMemoryUsage(processInfo.hProcess);
if (currentMemoryUsage > maxMemoryUsage) {
maxMemoryUsage = currentMemoryUsage;
}
if (memoryLimit != 0 && currentMemoryUsage > memoryLimit) {
killProcess(processInfo);
}
Sleep(200);
} while (getExitCode(processInfo.hProcess) == STILL_ACTIVE);

return maxMemoryUsage;
}

int main(){

SECURITY_ATTRIBUTES sa;
sa.nLength = sizeof(sa);
sa.lpSecurityDescriptor = NULL;
sa.bInheritHandle = TRUE;

HANDLE hInput = CreateFile("input.txt", GENERIC_READ, 0, &sa, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
if (hInput == INVALID_HANDLE_VALUE){
cout << "error: hInput" << endl;
return 0;
}

HANDLE hOutput = CreateFile("output.txt", GENERIC_WRITE, 0, &sa, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
if (hOutput == INVALID_HANDLE_VALUE){
cout << "error: hOutput" << endl;
return 0;
}

STARTUPINFO si = { 0 };
PROCESS_INFORMATION pi = { 0 };
si.cb = sizeof(STARTUPINFOW);
si.dwFlags = STARTF_USESTDHANDLES;
si.hStdInput = hInput;
si.hStdError = hOutput;
si.hStdOutput = hOutput;

//CREATE_SUSPENDED：新进程的主线程会以暂停的状态被创建，直到调用ResumeThread函数被调用时才运行
if (CreateProcess(NULL, "java Demo", NULL, NULL, TRUE, CREATE_SUSPENDED, NULL, NULL, &si, &pi)){

clock_t start, end;

//创建线程，计算最大使用内存；ref(pi)：传pi的引用
auto future = async(launch::async, getMaxMemoryUsage, ref(pi), 1024);
//唤醒线程
ResumeThread(pi.hThread);
start = clock();
WaitForSingleObject(pi.hProcess, INFINITE);
end = clock();
cout << (float)(end - start) / CLOCKS_PER_SEC << "s" << endl;
//终止进程
killProcess(pi);
cout << future.get() << "KB" << endl;

CloseHandle(hInput);
CloseHandle(hOutput);
}
else{
cout << "创建进程失败!" << endl;
HANDLE hProcess = GetCurrentProcess();
TerminateProcess(hProcess, 0);
}

return 0;
}

input.txt：
10 20



结果输出：
0.202s
112KB

output.txt：
30