OpenEuphoria

Re: pointers to variables

• Posted by bernie Aug 02, 2009
• 1206 views

This is a sample of how you can write assembler code in ver 4.0
of Euphoria with my include file.

I just would like to be able to do call_backs in DOS.

export function strlen(atom str) -- tested  
Asm("strlen_",  
"prolog4eu "&  
"cld "&  
"mov edi, [ebp+8] "&  
"xor eax, eax "&  
"or ecx, -1 "&  
"repne scasb "&  
"not ecx "&  
"dec ecx "&  
"mov eax, ecx "&  
"epilog4eu "&  
"ret 0 ",1,u)  
return f("strlen_",{str})  
end function  
--  
export function strspn(atom str1, atom str2) -- tested  
Asm("strspn_",  
"prolog4eu "&  
"cld "&  
"xor eax, eax "&  
"mov ecx, [ebp+8] "&  
"jmp ssp004 "&  
"ssp001: "&  
"inc ecx "&  
"mov edi, [ebp+12] "&  
"ssp002: "&  
"mov dh, [edi] "&  
"or dh, dh "&  
"jz ssp005 "&  
"cmp dl, dh "&  
"je ssp003 "&  
"inc edi "&  
"jmp ssp002 "&  
"ssp003: "&  
"inc eax "&  
"ssp004: "&  
"mov dl, [ecx] "&  
"or dl, dl "&  
"jnz ssp001 "&  
"ssp005: "&  
"epilog4eu "&  
"ret 0 ",2,u)  
return f("strspn_",{str1,str2})  
end function  
--  
export function strpbrk(atom str1, atom str2) -- tested  
Asm("strpbrk_",  
"prolog4eu "&  
"cld "&  
"mov eax, [ebp+8] "&  
"jmp sb004 "&  
"sb001: "&  
"mov ecx, [ebp+12] "&  
"sb002: "&  
"mov dh, [ecx] "&  
"or dh, dh "&  
"jz sb003 "&  
"cmp dl, dh "&  
"je sb005 "&  
"inc ecx "&  
"jmp sb002 "&  
"sb003: "&  
"inc eax "&  
"sb004: "&  
"mov dl, [eax] "&  
"or dl, dl "&  
"jnz sb001 "&  
"xor eax, eax "&  
"sb005: "&  
"epilog4eu "&  
"ret 0 ",2,u)  
return f("strpbrk_",{str1,str2})  
end function  
--  
export function strtok(atom buff, atom delim) -- tested  
Asm("strtok_",  
"prolog4eu         "& --  --  
"mov esi, [ebp+8]  "& --  get buffer  
"test esi esi      "& --  first call ?  
"jz nexttok        "& --  no  
"mov [@ptr], esi   "& --  save buffer  
"nexttok:          "& --  
"mov edi, [ebp+12] "& --  yes get delimit  
"mov esi, [@ptr]   "& --  get current ptr  
"cmp esi, 0        "& --  
"je near endtok    "& --  bail out  
"push edi          "& --  delimit  
"push esi          "& --  buffer  
"mov eax, "&AGet("strspn")& -- << ---- <<  THIS IS A CALL BACK  
"call near eax "& --  find start of token  
"add [@ptr], eax   "& --  goto first token  
"mov edi, [ebp+12] "& --  get delimit  
"mov esi, [@ptr]   "& --  get current ptr  
"cmp esi, 0        "& --  
"je near endtok    "& --  bail out  
"cmp [esi], 0      "& --  pointing to zero ?  
"je near endtok    "& --  bail out  
"push edi          "& --  delimit  
"push esi          "& --  buffer  
"mov eax, "&AGet("strpbrk")& -- << ---- <<  THIS IS A CALL BACK  
"call near eax     "& --  find the end of the token  
"mov esi, [@ptr]   "& --  get current ptr  
"cmp eax, esi      "& --  
"je near endtok    "& --  
"cmp eax, 0        "& --  
"je exact          "& --  
"mov [@ptr], eax   "& --  
"mov edi, eax      "& --  
"mov eax, 0        "& --  
"mov [edi], al     "& --  
"mov eax, esi      "& --  
"add [@ptr], 1     "& --  
"epilog4eu         "& --  
"ret 0             "& --  
"exact:            "& --  
"mov esi, [@ptr]   "& --  get current ptr  
"push esi          "& --  
"mov eax, "&AGet("strlen")& -- << ---- <<  THIS IS A CALL BACK  
"call near eax     "& --  
"cmp eax, 0        "& --  
"jne lasttok       "& --  
"jmp endtok        "& --  
"lasttok:          "& --  
"mov ecx, 0        "& --  
"mov eax, [@ptr]   "& --  get current ptr  
"mov [@ptr], ecx   "& --  block next call  
"epilog4eu         "& --  
"ret 0             "& --  
"endtok:           "& --  
"mov eax, 0        "& --  
"epilog4eu         "& --  
"ret 0             "& --  
"ptr: dd 0 ",2,u)  
return f("strtok_",{buff,delim})  
end function