Question

我正在尝试调用汇编程序，该程序应该从C app计算文件的CRC32校验和。

C代码：

    #include <stdio.h>
    #include <stdlib.h>
    #include <sys/stat.h>

    extern unsigned long __stdcall CRC32(size_t sizeOfFile, char buffer[]);


    int fsize(char* file) {
        int size;
        FILE* fh;

        fopen_s(&fh, file, "rb" );
        if(fh != NULL){
            if( fseek(fh, 0, SEEK_END) ){
                fclose(fh);
                return -1;
            }

            size = ftell(fh);
            fclose(fh);
            return size;
        }

        return -1; //error
    }

    void calculateChecksum(char * filename, char * checksum){
        FILE *file = NULL;

        unsigned long crc32;


        char hex[10];
        fopen_s(&file, filename, "rb" );
        size_t size = fsize(filename);
        char *buffer=(char*)malloc(size);
        fread_s(buffer,size,size,1,file);
        crc32=CRC32(size,buffer);
        int n = sprintf_s(hex,"%x",crc32);

        for (int i=0;i<8;i++){
            checksum[i]=hex[i];
        }
        fclose(file);
        file = NULL;
    }




    int main(){
        char checksum[8];
        calculateChecksum("B:\\secretMessageC#.txt",checksum);

        char hex[10];

        for (int i=0;i<8;i++){
            checksum[i]=hex[i];
            printf("%c",checksum[i]);
        }

        getchar();
        return 0;
    }

汇总代码：

    .686 
    .387
    .model flat, stdcall 
    .xmm
    .data
    .code
    CRC32 proc sizeOfFile:DWORD, file:DWORD
        push    esi
        push    ecx
        push    edx

        mov esi, file
        xor edx, edx
        or  eax, -1
        mov ecx, sizeOfFile

    CRC32_loop:
        mov dl, byte ptr [esi]
        xor dl, al
        shr eax, 8
        xor eax, dword ptr [crc32_table + 4*edx]
        inc esi
        dec ecx
        jnz CRC32_loop

        not eax

        pop edx
        pop ecx
        pop esi
        ret
            CRC32 endp
    crc32_table dd 000000000h, 077073096h, 0EE0E612Ch, 0990951BAh, 0076DC419h, 0706AF48Fh, 0E963A535h, 09E6495A3h, 00EDB8832h, 079DCB8A4h
                dd 0E0D5E91Eh, 097D2D988h, 009B64C2Bh, 07EB17CBDh, 0E7B82D07h, 090BF1D91h, 01DB71064h, 06AB020F2h, 0F3B97148h, 084BE41DEh
                dd 01ADAD47Dh, 06DDDE4EBh, 0F4D4B551h, 083D385C7h, 0136C9856h, 0646BA8C0h, 0FD62F97Ah, 08A65C9ECh, 014015C4Fh, 063066CD9h
                dd 0FA0F3D63h, 08D080DF5h, 03B6E20C8h, 04C69105Eh, 0D56041E4h, 0A2677172h, 03C03E4D1h, 04B04D447h, 0D20D85FDh, 0A50AB56Bh
                dd 035B5A8FAh, 042B2986Ch, 0DBBBC9D6h, 0ACBCF940h, 032D86CE3h, 045DF5C75h, 0DCD60DCFh, 0ABD13D59h, 026D930ACh, 051DE003Ah
                dd 0C8D75180h, 0BFD06116h, 021B4F4B5h, 056B3C423h, 0CFBA9599h, 0B8BDA50Fh, 02802B89Eh, 05F058808h, 0C60CD9B2h, 0B10BE924h
                dd 02F6F7C87h, 058684C11h, 0C1611DABh, 0B6662D3Dh, 076DC4190h, 001DB7106h, 098D220BCh, 0EFD5102Ah, 071B18589h, 006B6B51Fh
                dd 09FBFE4A5h, 0E8B8D433h, 07807C9A2h, 00F00F934h, 09609A88Eh, 0E10E9818h, 07F6A0DBBh, 0086D3D2Dh, 091646C97h, 0E6635C01h
                dd 06B6B51F4h, 01C6C6162h, 0856530D8h, 0F262004Eh, 06C0695EDh, 01B01A57Bh, 08208F4C1h, 0F50FC457h, 065B0D9C6h, 012B7E950h
                dd 08BBEB8EAh, 0FCB9887Ch, 062DD1DDFh, 015DA2D49h, 08CD37CF3h, 0FBD44C65h, 04DB26158h, 03AB551CEh, 0A3BC0074h, 0D4BB30E2h
                dd 04ADFA541h, 03DD895D7h, 0A4D1C46Dh, 0D3D6F4FBh, 04369E96Ah, 0346ED9FCh, 0AD678846h, 0DA60B8D0h, 044042D73h, 033031DE5h 
                dd 0AA0A4C5Fh, 0DD0D7CC9h, 05005713Ch, 0270241AAh, 0BE0B1010h, 0C90C2086h, 05768B525h, 0206F85B3h, 0B966D409h, 0CE61E49Fh
                dd 05EDEF90Eh, 029D9C998h, 0B0D09822h, 0C7D7A8B4h, 059B33D17h, 02EB40D81h, 0B7BD5C3Bh, 0C0BA6CADh, 0EDB88320h, 09ABFB3B6h
                dd 003B6E20Ch, 074B1D29Ah, 0EAD54739h, 09DD277AFh, 004DB2615h, 073DC1683h, 0E3630B12h, 094643B84h, 00D6D6A3Eh, 07A6A5AA8h 
                dd 0E40ECF0Bh, 09309FF9Dh, 00A00AE27h, 07D079EB1h, 0F00F9344h, 08708A3D2h, 01E01F268h, 06906C2FEh, 0F762575Dh, 0806567CBh
                dd 0196C3671h, 06E6B06E7h, 0FED41B76h, 089D32BE0h, 010DA7A5Ah, 067DD4ACCh, 0F9B9DF6Fh, 08EBEEFF9h, 017B7BE43h, 060B08ED5h
                dd 0D6D6A3E8h, 0A1D1937Eh, 038D8C2C4h, 04FDFF252h, 0D1BB67F1h, 0A6BC5767h, 03FB506DDh, 048B2364Bh, 0D80D2BDAh, 0AF0A1B4Ch
                dd 036034AF6h, 041047A60h, 0DF60EFC3h, 0A867DF55h, 0316E8EEFh, 04669BE79h, 0CB61B38Ch, 0BC66831Ah, 0256FD2A0h, 05268E236h
                dd 0CC0C7795h, 0BB0B4703h, 0220216B9h, 05505262Fh, 0C5BA3BBEh, 0B2BD0B28h, 02BB45A92h, 05CB36A04h, 0C2D7FFA7h, 0B5D0CF31h
                dd 02CD99E8Bh, 05BDEAE1Dh, 09B64C2B0h, 0EC63F226h, 0756AA39Ch, 0026D930Ah, 09C0906A9h, 0EB0E363Fh, 072076785h, 005005713h
                dd 095BF4A82h, 0E2B87A14h, 07BB12BAEh, 00CB61B38h, 092D28E9Bh, 0E5D5BE0Dh, 07CDCEFB7h, 00BDBDF21h, 086D3D2D4h, 0F1D4E242h 
                dd 068DDB3F8h, 01FDA836Eh, 081BE16CDh, 0F6B9265Bh, 06FB077E1h, 018B74777h, 088085AE6h, 0FF0F6A70h, 066063BCAh, 011010B5Ch
                dd 08F659EFFh, 0F862AE69h, 0616BFFD3h, 0166CCF45h, 0A00AE278h, 0D70DD2EEh, 04E048354h, 03903B3C2h, 0A7672661h, 0D06016F7h
                dd 04969474Dh, 03E6E77DBh, 0AED16A4Ah, 0D9D65ADCh, 040DF0B66h, 037D83BF0h, 0A9BCAE53h, 0DEBB9EC5h, 047B2CF7Fh, 030B5FFE9h
                dd 0BDBDF21Ch, 0CABAC28Ah, 053B39330h, 024B4A3A6h, 0BAD03605h, 0CDD70693h, 054DE5729h, 023D967BFh, 0B3667A2Eh, 0C4614AB8h
                dd 05D681B02h, 02A6F2B94h, 0B40BBE37h, 0C30C8EA1h, 05A05DF1Bh, 02D02EF8Dh   
    end

在建设过程中，我遇到了这三个错误：

    1>------ Build started: Project: ConsoleApplication5, Configuration: Debug Win32 ------
    1>  Assembling C:\Users\sliwkacz\Desktop\New folder\crc32.asm...
    1>C:\Users\sliwkacz\Desktop\New folder\crc32.asm(7): error A2206: missing operator in expression
    1>C:\Users\sliwkacz\Desktop\New folder\crc32.asm(12): error A2006: undefined symbol : file
    1>C:\Users\sliwkacz\Desktop\New folder\crc32.asm(15): error A2081: missing operand after unary operator
    1>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V110\BuildCustomizations\masm.targets(49,5): error MSB3721: The command "ml.exe /c /nologo /Zi /Fo"Debug\crc32.obj" /W3 /errorReport:prompt  /Ta"C:\Users\sliwkacz\Desktop\New folder\crc32.asm"" exited with code 1.
    ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

对于任何可以提供帮助的提示，我都会非常感激。

Answer 1

size是MASM程序集中的保留字，因此您必须为参数提供不同的名称。

您在CRC32 ENDP之后也错过了ret。

您可能需要将C文件中的函数声明更改为extern unsigned long __stdcall CRC32(size_t *bufLen, FILE *file);

从它的外观来看，你的CRC32函数正在以不正确的方式使用它的参数。 size参数是指向大小的指针，但您使用它就好像它是大小本身一样。
看起来你试图从FILE*读取，好像是指向文件中数据的指针，但我很确定FILE*只是指向结构的指针包含有关已打开文件的信息。要访问文件中的数据，您应该使用fread将数据块读入缓冲区。

将外部汇编程序函数添加到C项目中

1 个答案: