源代碼是由純匯編寫(xiě)的，如下：

;改進(jìn)型的bm匹配算法 支持中英文混合(即單字節與雙字節詞混合;用nasm編譯;函數原型;extern "C" bool sfstrstr(unsigned int td[256], const char* str1, const char* str2, char case_table[256]);;其中:;   td內的所有元素需在最初被初始化為0;   casetable是一個(gè)大小寫(xiě)轉換用的轉換表，加快大小寫(xiě)轉換的速度，需用如下的方法生成;   for(int i = 0; i < 256; ++i) ;      casetable[i] = tolower(i);;;如果匹配成功返回true(1), 否則返回false(0);;xieyubo@gmail.com;;Last Modified: 2005.10.15 [BITS 32][global sfstrstr] countstrlen:    xor eax, eax        _countstrlen_loop:    cmp [esi + eax], byte 0    je _countstrlen_exit    inc eax    jmp _countstrlen_loop     _countstrlen_exit:    ret lower:    mov al, [esp + 4]    and eax, 0xff    add eax, [ebp + 20]    mov al, [eax]    mov [esp + 4], al    ret getnumcnword:    xor eax, eax    xor ebx, ebx     _getnumcnword_loop:    cmp ebx, [ebp - 8]    je _getnumcnword_exit    mov edx, [ebp + 12]    add edx, ebx    test [edx], byte 0x80    jz _getnumcnword_loop_goto    inc eax        _getnumcnword_loop_goto:    inc ebx    jmp _getnumcnword_loop     _getnumcnword_exit:    ret inittd:    mov esi, [ebp + 16]    mov edi, [ebp + 8]    xor ecx, ecx          _inittd_loop:    mov eax, [ebp - 12]    cmp ecx, eax    jnl _inittd_exit    mov edx, eax    sub edx, ecx    push dword [esi + ecx]    call lower    pop eax    and eax, 0xff    mov [edi + eax * 4], edx        inc ecx    jmp _inittd_loop        _inittd_exit:    ret resettd:    mov esi, [ebp + 16]    mov edi, [ebp + 8]    xor ecx, ecx          _resettd_loop:    cmp ecx, [ebp - 12]    jnl _resettd_exit    push dword [esi + ecx]    call lower    pop eax    and eax, 0xff    mov [edi + eax * 4], dword 0        inc ecx    jmp _resettd_loop        _resettd_exit:    ret        sfstrstr:    push ebp    mov ebp, esp    sub esp, 20    push esi    push edi        ;;strlen(str1)    mov esi, [ebp + 12]    call countstrlen    mov [ebp - 16], eax        ;;strlen(str2)    mov esi, [ebp + 16]    call countstrlen    mov [ebp - 12], eax        call inittd        mov esi, [ebp + 16]    mov edi, [ebp + 12]    mov [ebp - 4], dword 0    mov [ebp - 8], dword 0        _sfstrstr_loop2:    xor ecx, ecx    mov eax, [ebp - 8]    add eax, [ebp - 12]    cmp eax, [ebp - 16]    jg  _sfstrstr_loop2_exit        _sfstrstr_loop3:    cmp ecx, [ebp - 12]    jnl _sfstrstr_loop3_exit    mov eax, [ebp - 8]    add eax, ecx    push dword [edi + eax]    call lower    pop ebx    push dword [esi + ecx]    call lower    pop edx    cmp bl, dl    jne _sfstrstr_loop3_exit    inc ecx    jmp _sfstrstr_loop3        _sfstrstr_loop3_exit:    cmp ecx, [ebp - 12]    jne _sfstrstr_goto1    call getnumcnword    test eax, 0x00000001    jz _sfstrstr_goto3    mov eax, [ebp - 12]    inc eax    add [ebp - 8], eax    jmp _sfstrstr_loop2     _sfstrstr_goto3:    mov [ebp - 4], dword 1    jmp _sfstrstr_loop2_exit     _sfstrstr_goto1:    mov eax, [ebp - 8]    add eax, [ebp - 12]    push dword [edi + eax]    call lower    pop eax    and eax, 0xff    shl eax, 2    add eax, [ebp + 8]    mov eax, [eax]    cmp eax, 0    je _sfstrstr_goto2    add [ebp - 8], eax    jmp _sfstrstr_loop2     _sfstrstr_goto2:    mov eax, [ebp - 12]    inc eax    add [ebp - 8], eax    jmp _sfstrstr_loop2     _sfstrstr_loop2_exit:    call resettd    mov eax, [ebp - 4]        return:    pop edi    pop esi    mov esp, ebp    pop ebp    ret