regarding convert win32 C macro FD_SET (network) to fasm

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vbVeryBeginner

Joined: 15 Aug 2004
Posts: 884
Location: \\world\asia\malaysia

vbVeryBeginner 18 Mar 2006, 15:13

hi, i just did the fasm FD_SET based on the C macro, could anyone verify for

me, is the below proc FD_SET correct or not?
thanks a lot.

Code:


fdsize  equ     64 ; or any number to test

struct fd_set
        fd_count        dd ?
        fd_array        rd fdsize
ends

proc FD_SET fd,set
        push eax ebx ecx edx
        mov  ebx,[fd]           ; ebx = fd
        mov  edx,[set]
        push edx
        mov  eax,[edx]          ; eax = fd_count
        add  edx,4                      ; edx = starting of fd_array
        mov  ecx,0

        @@:
                cmp  ecx,eax
                jge  @f
                cmp  [edx],ebx
                je   .finish
                add  edx,4
                inc  ecx
                jmp  @b
        @@:

        cmp  ecx,eax
        jne  .finish
        cmp  ecx,fdsize
        jg   .finish
        push ebx
        pop  dword [edx]
        pop  edx
        inc  dword [edx]
        .finish:

        pop  edx ecx ebx eax
        ret
endp

;from winsock2.h
;
;typedef struct fd_set {
;        u_int fd_count;               /* how many are SET? */
;        SOCKET  fd_array[FD_SETSIZE];   /* an array of SOCKETs */
;} fd_set;
;
;
;
;#define FD_SET(fd, set) do { \
;    u_int __i; \
;    for (__i = 0; __i < ((fd_set FAR *)(set))->fd_count; __i++) { \
;        if (((fd_set FAR *)(set))->fd_array[__i] == (fd)) { \
;;            break; \
;        } \
;    } \
;    if (__i == ((fd_set FAR *)(set))->fd_count) { \
;        if (((fd_set FAR *)(set))->fd_count < FD_SETSIZE) { \
;            ((fd_set FAR *)(set))->fd_array[__i] = (fd); \
;            ((fd_set FAR *)(set))->fd_count++; \
;        } \
;    } \
;} while(0)

18 Mar 2006, 15:13

Nikolay Petrov

Joined: 22 Apr 2004
Posts: 101
Location: Bulgaria

Nikolay Petrov 19 Mar 2006, 20:39

its a proc variant of FD_SET macro from winsock2.h

Code:

fdsize  =  64
proc FD_SET fd,set; fd is unsigned, set is offset fd_set struct
        mov     edx,[set]
        mov     ecx,[fd]
        xor     eax,eax
        jmp     .while
.do:
        cmp     ecx,[edx+4*(eax+1)]
        je      .endw
        inc     eax
.while:
        cmp     eax,[edx]
        jb      .do
.endw:
        cmp     eax,[edx]
        jne     @f
        cmp     [edx],fdsize
        jae     @f
        mov     [edx+4*(eax+1)],ecx
        inc     [edx]
@@:
        ret
endp

_________________
regards

19 Mar 2006, 20:39

vbVeryBeginner

Joined: 15 Aug 2004
Posts: 884
Location: \\world\asia\malaysia

vbVeryBeginner 20 Mar 2006, 07:00

oh,thanks nikolay petrov,
btw, the FD_SET i posted works on my application Smile

here is the FD_CLR,

Code:

proc FD_CLR fd,set
        push eax ebx ecx edx
        mov  ebx,[fd]                   ; ebx = fd
        mov  edx,[set]
        mov  eax,[edx]                  ; eax = fd_count
        add  edx,4                              ; so that EDX reffer to fd_array, (skip the fd_count)
        mov  ecx,0
        @@:
                cmp  ecx,eax
                jge  .finish
                cmp  ebx,[edx]
                je   .relocate
                inc  ecx
                jmp  @b

        .relocate:
                cmp  ecx,eax
                je   .reduce
                push dword [edx+4]
                pop  dword [edx]
                inc  ecx
                add  edx,4
                jmp  .relocate
        
        .reduce:                                ; fd_count--
                dec  [set]

        .finish:
        pop  edx ecx ebx eax
                        ret
endp

tested and work correctly.

20 Mar 2006, 07:00

Nikolay Petrov

Joined: 22 Apr 2004
Posts: 101
Location: Bulgaria

Nikolay Petrov 20 Mar 2006, 11:25

i don't think. the proc wasn't wrote very correctly, if we see the macro.
for example fd and fd_array is unsigned, but you checked signed;
dec [set] -??? its equ dec[ebp+12], but [ebp+12]=[set] and will be no effect into set.fd_count, when proc finish.
next is a not bad solution

Code:

proc FD_CLR fd,set
        mov     edx,[set]
        mov     ecx,[fd]
        xor     eax,eax
        jmp     .in_for
.for:
        cmp     ecx,[edx+4*(eax+1)]
        jne     .continue
        jmp     .while
.do:
        mov     ecx,dword ptr [edx+4*(eax+2)]
        mov     [edx+4*(eax+1)],ecx
        inc     eax
.while:
        mov     ecx,[edx]
        dec     ecx
        cmp     eax,ecx
        jb      .do
        dec     [edx]
        ret 
.continue:
        inc     eax
.in_for:
        cmp     eax,[edx]
        jb      .for
        ret
endp

Code:

proc FD_CLR fd,set

        mov     edx,[set]
        mov     ecx,[fd]
        xor     eax,eax
        jmp     .while
.do:
        cmp     ecx,[edx+4*(eax+1)]
        je      .endw
        inc     eax
.while:
        cmp     eax,[edx]
        jb      .do
        ret
.endw:
        push    ebx
        mov     ebx,[edx]
        dec     ebx
        jmp     .while2
.do2:
        mov     ecx,[edx+4*(eax+2)]
        mov     [edx+4*(eax+1)],ecx
        inc     eax
.while2:
        cmp     eax,ebx
        jb      .do2
        dec     [edx]
        pop     ebx
        ret
endp

by the way, if it isn't a secret why do you copy winsock macros?

_________________
regards

20 Mar 2006, 11:25

vbVeryBeginner

Joined: 15 Aug 2004
Posts: 884
Location: \\world\asia\malaysia

vbVeryBeginner 20 Mar 2006, 23:29

oh yeah,
my mistake Embarassed

20 Mar 2006, 23:29

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