我想在 MASM 中转换以下 C++ 程序（目标是打开一个现有文件，向其中写入一个字符串，最后读取文件）：
void __cdecl _tmain(int argc, TCHAR *argv[])
{
HANDLE hFile;
/////////////////////////////////////////////////////////////////////////////////
if ((hFile = CreateFile(TEXT("C:\\Users\\Bloodsucker94\\Desktop\\TestFile.txt"),
GENERIC_WRITE | GENERIC_READ,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL)) == INVALID_HANDLE_VALUE)
_tprintf(TEXT("CreateFile() failed code %d\n"), GetLastError());
/////////////////////////////////////////////////////////////////////////////////
char DataBuffer[1024] = "aaa";
DWORD dwBytesToWrite = (DWORD)strlen(DataBuffer);
DWORD dwBytesWritten = 0;
//_tprintf(TEXT("CreateFile() HFILE=%d\n"), hFile);
if (WriteFile(hFile, DataBuffer, dwBytesToWrite, &dwBytesWritten, NULL) == FALSE)
_tprintf(TEXT("WriteFile() failed code %d\n"), GetLastError());
//_tprintf(TEXT("WriteFile() HFILE=%d\n"), hFile);
/////////////////////////////////////////////////////////////////////////////////
SetFilePointer(hFile, 0, NULL, FILE_BEGIN);
char ReadBuffer[4096] = {0};
DWORD dwBytesRead;
if (FALSE == ReadFile(hFile, ReadBuffer, 4096, &dwBytesRead, NULL))
_tprintf(TEXT("ReadFile() failed code %d\n"), GetLastError());
printf("|%s|", ReadBuffer);
getchar();
CloseHandle(hFile);
}
ASM 代码：
.386
.model flat, stdcall
option casemap :none
include \masm32\include\windows.inc
include \masm32\include\kernel32.inc
include \masm32\include\masm32.inc
includelib \masm32\lib\kernel32.lib
includelib \masm32\lib\masm32.lib
include \masm32\include\msvcrt.inc
includelib \masm32\lib\msvcrt.lib
.data
FileName BYTE "HelloWorld.txt", 0
BufferToWrite BYTE "Hell yeaahhhhhh!!!!", 0
ErrorCreateMsgFormat BYTE "CreateFile() failed with code %d", 0
ErrorReadMsgFormat BYTE "ReadFile() failed with code %d", 0
ErrorWriteMsgFormat BYTE "WriteFile() failed with code %d", 0
CheckFormat BYTE "hFile=%d", 0
CheckSize BYTE "size=%d", 0
CheckPtr BYTE "EAX_ADDR=Ox%08X", 0
OutputFormat BYTE "output=%s", 0
.data?
hFile HANDLE ?
hFileCopy HANDLE ?
FileSize DWORD ?
hMem LPVOID ?
BytesRead LPDWORD ?
ErrorCode DWORD ?
RetRead BOOL ?
RetWrite BOOL ?
NumberOfBytesToWrite DWORD ?
NumberOfBytesWritten DWORD ?
BufferToWriteSize DWORD ?
.code
start:
invoke lstrlen, ADDR BufferToWrite
mov BufferToWriteSize, eax
;-----------------------------CREATE-------------------------------
invoke CreateFile, ADDR FileName, \
GENERIC_WRITE + GENERIC_READ, \
0, \
NULL, \
OPEN_EXISTING, \
FILE_ATTRIBUTE_NORMAL, \
NULL
mov hFile, eax
.IF hFile == INVALID_HANDLE_VALUE
invoke GetLastError
mov ErrorCode, eax
invoke crt_printf, ADDR ErrorCreateMsgFormat, \
ErrorCode
jmp _quit
.ENDIF
invoke crt_printf, ADDR CheckFormat, \
hFile
;---------------------------WRITE---------------------------------
invoke WriteFile, hFile, \
ADDR BufferToWrite, \
BufferToWriteSize, \
ADDR NumberOfBytesWritten, \
NULL
mov RetWrite, eax
.IF RetWrite == FALSE
invoke GetLastError
mov ErrorCode, eax
invoke crt_printf, ADDR ErrorWriteMsgFormat, \
ErrorCode
jmp _quit
.ENDIF
invoke crt_printf, ADDR CheckFormat, \
hFile
;--------------------------READ----------------------------------
invoke GetFileSize, eax, \ ;problem start here
NULL
mov FileSize, eax
inc eax
invoke crt_printf, ADDR CheckSize, \
FileSize
invoke GlobalAlloc, GMEM_FIXED, \
eax
mov hMem, eax
add eax, FileSize
mov BYTE PTR [eax], 0
invoke ReadFile, hFile, \
hMem, \
FileSize, \
ADDR BytesRead, \
NULL
mov RetRead, eax
.IF RetRead == FALSE
invoke GetLastError
mov ErrorCode, eax
invoke crt_printf, ADDR ErrorReadMsgFormat, \
ErrorCode
jmp _quit
.ENDIF
invoke crt_printf, ADDR CheckFormat, \
hFile
invoke crt_printf, ADDR OutputFormat, \
hMem
invoke CloseHandle, hFile
invoke GlobalFree, hMem
_quit:
invoke ExitProcess, 0
end start
问题是 EAX 寄存器不包含 CreateFile 返回值 (hFile)。这是正常的，因为它在执行时包含了 WriteFile 函数的值。我没有找到任何解决方案来保存 CreatefILE 函数返回的 eax 的初始值，并在 WriteFile 函数调用后再次使用它。我不能这样做：
mov FileSize, hFile
我只想保存 eax 的第一个值。我试图将它保存到另一个寄存器中，但它不起作用。有人可以帮助我吗？