BOOL WINAPI DetourReplaceExport(HMODULE hModule, PCSTR pszExportName, PVOID *ppCode)
{
    PIMAGE_DOS_HEADER pDosHeader = (PIMAGE_DOS_HEADER)hModule;
    if (hModule == NULL) {
        pDosHeader = (PIMAGE_DOS_HEADER)GetModuleHandle(NULL);
    }

    __try {
        if (pDosHeader->e_magic != IMAGE_DOS_SIGNATURE) {
            SetLastError(ERROR_BAD_EXE_FORMAT);
            return NULL;
        }

        PIMAGE_NT_HEADERS pNtHeader = (PIMAGE_NT_HEADERS)((PBYTE)pDosHeader +
                                                          pDosHeader->e_lfanew);
        if (pNtHeader->Signature != IMAGE_NT_SIGNATURE) {
            SetLastError(ERROR_INVALID_EXE_SIGNATURE);
            return FALSE;
        }
        if (pNtHeader->FileHeader.SizeOfOptionalHeader == 0) {
            SetLastError(ERROR_EXE_MARKED_INVALID);
            return FALSE;
        }

        PIMAGE_EXPORT_DIRECTORY pExportDir
            = (PIMAGE_EXPORT_DIRECTORY)
            RvaAdjust(pDosHeader,
                      pNtHeader->OptionalHeader
                      .DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress);

        if (pExportDir == NULL) {
            SetLastError(ERROR_EXE_MARKED_INVALID);
            return FALSE;
        }

        PDWORD pdwFunctions = (PDWORD)RvaAdjust(pDosHeader, pExportDir->AddressOfFunctions);
        PDWORD pdwNames = (PDWORD)RvaAdjust(pDosHeader, pExportDir->AddressOfNames);
        PWORD pwOrdinals = (PWORD)RvaAdjust(pDosHeader, pExportDir->AddressOfNameOrdinals);

        for (DWORD nFunc = 0; nFunc < pExportDir->NumberOfFunctions; nFunc++) {
            PBYTE pbCode = (pdwFunctions != NULL)
                ? (PBYTE)RvaAdjust(pDosHeader, pdwFunctions[nFunc]) : NULL;
            PCHAR pszName = NULL;
            for (DWORD n = 0; n < pExportDir->NumberOfNames; n++) {
                if (pwOrdinals[n] == nFunc) {
                    pszName = (pdwNames != NULL)
                        ? (PCHAR)RvaAdjust(pDosHeader, pdwNames[n]) : NULL;
                    break;
                }
            }

            if( (pszName != NULL) && (ppCode != NULL) && (strcmp(pszName, pszExportName) == 0) )
            {
                PVOID dwReplace = *ppCode;
                DWORD dwOldProtect = 0;
                if(VirtualProtect(&pdwFunctions[nFunc], 0x04, PAGE_EXECUTE_READWRITE, &dwOldProtect))
                {
                    *ppCode = pbCode;
                    pdwFunctions[nFunc] = (DWORD)dwReplace - (DWORD)pDosHeader;
                    VirtualProtect(&pdwFunction[nFunc], 0x04, dwOldProtect, &dwOldProtect);
                }
                break;
            }
        }
        SetLastError(NO_ERROR);
        return TRUE;
    }
    __except(EXCEPTION_EXECUTE_HANDLER) {
        SetLastError(ERROR_EXE_MARKED_INVALID);
        return NULL;
    }
}