Element MemoryStream

GlobalConst
  implements_IStream ClassName

Vars
  Self#.IStrm   dd ?
  Self#.bPos    dd ?
  Self#.ePos    dd ?
  Self#.bufPtr  dd ?
  Self#.bufSize dd ?

GlobalProc

  proc ClassName#.IStream.Seek self,offset,origin
    push esi
    mov esi,[self]
    cmp byte [origin],2
    jne @f
    mov eax,[pMemoryStream.ePos]
    add eax,[offset]
    jmp .ok1
 @@:cmp byte [origin],1
    jne @f
    mov eax,[pMemoryStream.bPos]
    add eax,[offset]
    jmp .ok1
 @@:mov eax,[offset]
  .ok1:
    cmp eax,[pMemoryStream.ePos]
    jbe @f
    mov eax,[pMemoryStream.ePos]
 @@:mov [pMemoryStream.bPos],eax
    pop esi
    ret
  endp

  proc ClassName#.IStream.GetSize self
    push esi
    mov esi,[self]
    mov eax,[pMemoryStream.ePos]
    pop esi
    ret
  endp

  proc ClassName#.IStream.SetSize self,size
    push esi
    mov esi,[self]
    mov eax,[size]
    mov [pMemoryStream.ePos],eax
    cmp eax,[pMemoryStream.bufSize]
    jbe .exit
    and eax,-400h
    add eax,400h
    mov [pMemoryStream.bufSize],eax
    mov edx,eax
    mov eax,[pMemoryStream.bufPtr]
    call __realloc
    mov [pMemoryStream.bufPtr],eax
  .exit:
    pop esi
    ret
  endp

  proc ClassName#.IStream.Read self,buf,len
    push esi
    mov esi,[self]
    mov eax,[pMemoryStream.ePos]
    sub eax,[pMemoryStream.bPos]
    cmp eax,[len]
    jae @f
    mov [len],eax
 @@:mov edx,[pMemoryStream.bufPtr]
    add edx,[pMemoryStream.bPos]
    mov eax,[buf]
    mov ecx,[len]
    add [pMemoryStream.bPos],ecx
    call __memcpy
    pop esi
    ret
  endp

  proc ClassName#.IStream.Write self,buf,len
    push esi
    mov esi,[self]
    mov eax,[pMemoryStream.bPos]
    add eax,[len]
    cmp eax,[pMemoryStream.bufSize]
    jbe .ok
    and eax,-400h
    add eax,400h
    mov [pMemoryStream.bufSize],eax
    mov edx,eax
    mov eax,[pMemoryStream.bufPtr]
    call __realloc
    mov [pMemoryStream.bufPtr],eax
  .ok:
    mov eax,[pMemoryStream.bufPtr]
    add eax,[pMemoryStream.bPos]
    mov edx,[buf]
    mov ecx,[len]
    add [pMemoryStream.bPos],ecx
    call __memcpy
    mov eax,[pMemoryStream.bPos]
    cmp eax,[pMemoryStream.ePos]
    jbe .exit
    mov [pMemoryStream.ePos],eax
  .exit:
    pop esi
    ret
  endp

  proc ClassName#.IStream.Close self
    push esi
    mov esi,[self]
    xor eax,eax
    mov [pMemoryStream.bPos],eax
    mov [pMemoryStream.ePos],eax
    pop esi
    ret
  endp

Create
  mov [Self#.IStrm],ClassName#.IStream
  xor eax,eax
  mov [Self#.bPos],eax
  if Self#.prop.Stream eq 0
    mov [Self#.ePos],eax
    mov eax,400h
    mov [Self#.bufSize],eax
    call __alloc
    mov [Self#.bufPtr],eax
  else
    invoke FindResource,[hinstance],Self#.prop.Stream,100
    push eax
    invoke SizeofResource,[hinstance],eax
    mov [Self#.bufSize],eax
    mov [Self#.ePos],eax
    call __alloc
    mov [Self#.bufPtr],eax
    pop eax
    invoke LoadResource,[hinstance],eax
    invoke LockResource,eax
    mov edx,eax
    mov eax,[Self#.bufPtr]
    mov ecx,[Self#.bufSize]
    call __memcpy
  end if

PointWork doCopy
EndPoint

PointWork doClear
  xor eax,eax
  mov [Self#.bPos],eax
  mov [Self#.ePos],eax
EndPoint

PointWork doPosition
  \local pos
  ReadInt pos,data,data.type,Self#.Position,0
  mov_ex eax,pos
  lea ecx,[Self#.IStrm]
  stdcall ClassName#.IStream.Seek,ecx,eax,0
EndPoint

PointVar Stream,data_stream
  lea eax,[Self#.IStrm]
  result equ eax
EndPoint

PointVar Size,data_int
  result equ [Self#.ePos]
EndPoint

PointVar Position,data_int
  result equ [Self#.bPos]
EndPoint

EndElement