MASM32连接程序时error A2006: undefined symbol : u

落日映苍穹つ 2024-03-31 12:04 54阅读 0赞

为了检测Windows操作系统是32位还是64位的，用MASM32编写了一个调用Windows API函数GetNativeSystemInfo的程序（完整代码附后），GetNativeSystemInfo函数会将指向SYSTEM\_INFO结构体的地址存到GetNativeSystemInfo传递的参数中。

微软官网中的STEM\_INFO定义为：

typedef struct _SYSTEM_INFO {
      union {
        DWORD dwOemId;
        struct {
          WORD wProcessorArchitecture;
          WORD wReserved;
        } DUMMYSTRUCTNAME;
      } DUMMYUNIONNAME;
      DWORD     dwPageSize;
      LPVOID    lpMinimumApplicationAddress;
      LPVOID    lpMaximumApplicationAddress;
      DWORD_PTR dwActiveProcessorMask;
      DWORD     dwNumberOfProcessors;
      DWORD     dwProcessorType;
      DWORD     dwAllocationGranularity;
      WORD      wProcessorLevel;
      WORD      wProcessorRevision;
    } SYSTEM_INFO, *LPSYSTEM_INFO;

SYSTEM\_INFO中的wProcessorArchitecture存储了已安装操作系统的处理器体系结构。

访问代码为：

mov  eax, g_lpSI
                     mov  ax,  (SYSTEM_INFO ptr [eax]).DUMMYUNIONNAME.DUMMYSTRUCTNAME.wProcessorArchitecture
                     and  eax, 0ffffh
                     .if (eax==PROCESSOR_ARCHITECTURE_AMD64) || (eax==PROCESSOR_ARCHITECTURE_IA64) || (eax==PROCESSOR_ARCHITECTURE_ARM64)
                         mov eax, OFFSET g_sz64Bit
                     .else
                         mov eax, OFFSET g_sz32Bit
                     .endif

需要注意的两点，一是wProcessorArchitecture是word型数据，只有16位。二是MASM32中没有定义PROCESSOR\_ARCHITECTURE\_ARM64，在微软网官上其值为12。

PROCESSOR_ARCHITECTURE_ARM64   equ 12     ;ARM64

但是在连接程序时总是提示 32or64.asm(54) : error A2006: undefined symbol : u

![1662e82eb5b445648f883b51d2e6753d.jpeg][]  
第54行代码就是

mov  ax,  (SYSTEM_INFO ptr [eax]).DUMMYUNIONNAME.DUMMYSTRUCTNAME.wProcessorArchitecture

里面并没有使用符号u。

MASM32中的SYSTEM\_INFO结构定义存在windows.inc中，居然跟微软官网上的不同：

SYSTEM_INFO STRUCT
      wProcessorArchitecture        WORD       ?
      wReserved                     WORD       ?
      dwPageSize                    DWORD      ?
      lpMinimumApplicationAddress   DWORD      ?
      lpMaximumApplicationAddress   DWORD      ?
      dwActiveProcessorMask         DWORD      ?
      dwNumberOfProcessors          DWORD      ?
      dwProcessorType               DWORD      ?
      dwAllocationGranularity       DWORD      ?
      wProcessorLevel               WORD       ?
      wProcessorRevision            WORD       ?
    SYSTEM_INFO ENDS

MASM32中的SYSTEM\_INFO结构定义代码中省略了微软官网其中的DUMMYUNIONNAME联合体和DUMMYSTRUCTNAME结构体，难怪使用.DUMMYUNIONNAME.DUMMYSTRUCTNAME.wProcessorArchitecture来访问在连接时会出错，奇怪的是出错信息里没有提示DUMMYUNIONNAME.DUMMYSTRUCTNAME未定义，而是莫明奇妙的u

将第54行代码改为

mov  ax,  (SYSTEM_INFO ptr [eax]).wProcessorArchitecture

后顺利完成连接，生成了EXE文件，但是更大的麻烦来了……

附完整·代码：

;<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
    ; 32or64.asm
    ;<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
    
    .586
    .model     flat, stdcall
    option     casemap:none
    include    \masm32\include\windows.inc
    include    \masm32\include\kernel32.inc
    includelib \masm32\lib\kernel32.lib
    include    \masm32\include\user32.inc
    includelib \masm32\lib\user32.lib
    
    ;sssssssssssssssssssssssssssssssssssssss
    ;.const
    ;sssssssssssssssssssssssssssssssssssssss
    ;PROCESSOR_ARCHITECTURE_INTEL   equ 0      ;x86
    ;PROCESSOR_ARCHITECTURE_ARM     equ 5      ;ARM
    ;PROCESSOR_ARCHITECTURE_IA64    equ 6      ;基于 Intel Itanium 的
    ;PROCESSOR_ARCHITECTURE_AMD64   equ 9      ;x64 (AMD 或 Intel)
    PROCESSOR_ARCHITECTURE_ARM64   equ 12     ;ARM64
    ;PROCESSOR_ARCHITECTURE_UNKNOWN equ 0ffffh ;未知体系结构。
    
    
    _SYSTEM_INFO STRUCT
       UNION
         dwOemId DWORD ?
         STRUCT
            wProcessorArchitecture        WORD       ?
            wReserved                     WORD       ?
         ENDS
      ENDS
      dwPageSize                    DWORD      ?
      lpMinimumApplicationAddress   DWORD      ?
      lpMaximumApplicationAddress   DWORD      ?
      dwActiveProcessorMask         DWORD      ?
      dwNumberOfProcessors          DWORD      ?
      dwProcessorType               DWORD      ?
      dwAllocationGranularity       DWORD      ?
      wProcessorLevel               WORD       ?
      wProcessorRevision            WORD       ?
    _SYSTEM_INFO ENDS
    
    ;sssssssssssssssssssssssssssssssssssssss
    .data
    ;sssssssssssssssssssssssssssssssssssssss
    g_szCaption               db    "Windows",0
    g_sz32Bit                 db    "32位",0
    g_sz64Bit                 db    "64位",0
    g_szGetNativeSystemInfo   db    "GetNativeSystemInfo", 0
    g_szkernel32Dll           db    "kernel32.dll", 0
    g_szFailGetModuleHandle   db    "GetModuleHandle失败", 0
    g_szFailGetProcAddress    db    "GetProcAddress失败", 0
    g_lpfnGetNativeSystemInfo dword ?
    g_lpSI                    dword ?  ; SYSTEM_INFO
    
    
    ;sssssssssssssssssssssssssssssssssssssss
    .code
    ;sssssssssssssssssssssssssssssssssssssss
    start:
          invoke GetModuleHandle, OFFSET g_szkernel32Dll
          .if    eax==NULL
                 mov eax, OFFSET g_szFailGetModuleHandle
          .else
                 invoke GetProcAddress, eax, OFFSET g_szGetNativeSystemInfo
                 .IF eax==NULL
                     mov eax, OFFSET g_szFailGetProcAddress
                 .ELSE
                     mov  g_lpfnGetNativeSystemInfo, eax
                     push OFFSET g_lpSI
                     call g_lpfnGetNativeSystemInfo
                     mov  eax, g_lpSI
                     mov  ax, (SYSTEM_INFO ptr [eax]).wProcessorArchitecture
                     and  eax, 0ffffh 
                     ;mov  eax, (_SYSTEM_INFO ptr [eax]).dwOemId
                     .if (eax==PROCESSOR_ARCHITECTURE_IA64) || (eax==PROCESSOR_ARCHITECTURE_AMD64) || (eax==PROCESSOR_ARCHITECTURE_ARM64)
                         mov eax, OFFSET g_sz64Bit
                     .else
                         mov eax, OFFSET g_sz32Bit
                     .endif
                 .ENDIF
          .endif
          invoke MessageBox, NULL, eax, OFFSET g_szCaption, MB_OK
          invoke ExitProcess, NULL
    end start

[1662e82eb5b445648f883b51d2e6753d.jpeg]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/31/1a8fbad61604459cb912b39dc0dffeeb.jpeg