Windows 核心編程之 異常處理

下面程式是一個數組，預定了記憶體，但是沒有分配實體記憶體。利用異常處理不可訪問，當寫入資料時，會觸發異常，然後申請記憶體，這樣就節省了記憶體使用量率

// SEH.cpp : Defines the entry point for the console application.//#include "stdafx.h"#include <Windows.h>#include <stdio.h>#include <assert.h>#include <Strsafe.h>typedef struct MyTest{char name[10];int  age;}CELL,*PCELL;const int g_h = 1024;const int g_l = 512;int g_len = 1024 * 512;typedef CELL MyStruct[g_h][g_l];MyStruct* pMyTest = NULL;void Init(PBYTE* pData, DWORD dwsize){*pData =(PBYTE)VirtualAlloc(NULL, dwsize, MEM_RESERVE | MEM_TOP_DOWN, PAGE_READWRITE);assert(NULL != pData);}LONG ExceptionFilter(PEXCEPTION_POINTERS pep, DWORD dwSize){// Default to trying another filter (safest thing to do)LONG lDisposition = EXCEPTION_EXECUTE_HANDLER;;// We only fix access violationsif (pep->ExceptionRecord->ExceptionCode != EXCEPTION_ACCESS_VIOLATION)return(EXCEPTION_CONTINUE_EXECUTION);// Get address of attempted access and get attempted read or writePVOID pvAddrTouched = (PVOID) pep->ExceptionRecord->ExceptionInformation[1];BOOL bAttemptedRead = (pep->ExceptionRecord->ExceptionInformation[0] == 0);void* pAddress = pMyTest;// Is attempted access within this VMArray's reserved region?if ((pAddress <= pvAddrTouched) && (pvAddrTouched < ((PBYTE) pAddress + dwSize))) {TCHAR sz[200];StringCchPrintf(sz, _countof(sz), TEXT("Violation: Attempting to %s"),bAttemptedRead ? TEXT("Read") : TEXT("Write"));printf("%S\n",sz);if (!bAttemptedRead) {BOOL bCommittedStorage = FALSE;  // Assume committing storage failsdo {bCommittedStorage = (NULL != VirtualAlloc(pvAddrTouched, sizeof(CELL), MEM_COMMIT, PAGE_READWRITE));if (!bCommittedStorage ) {MessageBox(NULL, TEXT("Please close some other applications and Press OK."), TEXT("Insufficient Memory Available"), MB_ICONWARNING | MB_OK);}} while (!bCommittedStorage);lDisposition = (bCommittedStorage ? EXCEPTION_CONTINUE_EXECUTION : EXCEPTION_EXECUTE_HANDLER);}}return(lDisposition);}static LONG WINAPI MYhandledExceptionFilter(PEXCEPTION_POINTERS pep) {MessageBoxA(NULL,"1","1",MB_OK);return EXCEPTION_EXECUTE_HANDLER;}int _tmain(int argc, _TCHAR* argv[]){// HMODULE hmudule = LoadLibrary("kernel32.dll");// PUNHANDLEDEXCEPTIONFILTER = (PUNHANDLEDEXCEPTIONFILTER)GetProcAddress(hmudule,// "");SetUnhandledExceptionFilter(MYhandledExceptionFilter);int i = 0;strlen(NULL);int j = 10 / i;Init((PBYTE*)&pMyTest,g_len);__try{int a = (*pMyTest)[0][0].age;}__except(ExceptionFilter(GetExceptionInformation(),g_len)){printf("111\n");}__try{(*pMyTest)[0][0].age = 10;(*pMyTest)[0][1].age = 11;(*pMyTest)[0][2].age = 11;}__except(ExceptionFilter(GetExceptionInformation(),g_len)){printf("222\n");}getchar();return 0;}