Question about WinApi1.o2bas

[Arnold]

Hi Charles,

hopefully you do not think I am unbalanced, jumping from topic to topic. But this is something which is on my 'must know' list since I started to learn Oxygenbasic.

I am able to run \examples\Asm32\WinApi1.o2bas if I comment out the #asm statement. I can also compile to an exe file which depends on Oxygen.dll. But I cannot create an independent executable using RTL32.inc. I assume there are statements in WinApi.o2bas which conflict with RTL32.inc. Which modifications are needed in WinApi1.o2bas to create an independent exe file using as many assembler instructions as possible?

There is an intention with this question. I always wanted to realize some of the existing asm tutorials using Oxygenbasic but I do not really know where to start. It would be interesting to see how much Basic is in fact necessary to create WinApi1.exe and to what extent assembly can be used.

Roland

[Arnold]

This is what I mean:

I took Iczelion tutorial no.3 line by line and searched for what would make sense to do in assembly. But I always ended in Basic. I think it does not make sense to use assembly statements for things which Oxygenbasic already does for me and which I cannot do better.

So probably for WinMain, the wndproc callbacks and Windows functions there will be no need for extra assembly. But in case of user functions and subs when would it be advantageous to use assembler?

Roland

Code: OxygenBasic

1. '.386
2. '.model flat,stdcall
3. 'option casemap:none
4. 'include \masm32\include\windows.inc
5. 'include \masm32\include\user32.inc
6. 'include \masm32\include\kernel32.inc
7. 'includelib \masm32\lib\user32.lib
8. 'includelib \masm32\lib\kernel32.lib
9.  
10. #compact
11.  
12. $ filename "Win.exe"
13. 'include "$inc/RTL32.inc"
14. include "$inc/minwin.inc"
15.  
16. % COLOR_WINDOW=5
17.  
18. 'WinMain proto :DWORD,:DWORD,:DWORD,:DWORD
19. declare sub WinMain(sys hInst,hPrevInst, asciiz* CmdLine, sys CmdShow)
20.  
21. '.data
22. 'ClassName db "SimpleWinClass",0
23. 'AppName  db "Our First Window",0
24. zstring ClassName="SimpleWinClass"
25. zstring AppName="Our First Window"
26.  
27. '.data?
28. 'hInstance dd ?
29. 'CommandLine dd ?
30. sys hInstance
31. asciiz ptr CommandLine
32.  
33. '.code
34. 'start:
35. '    invoke GetModuleHandle, NULL
36. '    mov    hInstance,eax
37. hInstance=GetModuleHandle NULL
38. '    invoke GetCommandLine
39. '    mov    CommandLine,eax
40. &CommandLine=GetCommandLine
41. '    invoke WinMain, hInstance, NULL, CommandLine, SW_SHOWDEFAULT
42. WinMain hInstance, NULL, CommandLine, SW_SHOWDEFAULT
43. '    invoke ExitProcess, eax
44.  
45. 'WinMain proc hInst:HINSTANCE, hPrevInst:HINSTANCE, CmdLine:LPSTR, CmdShow:DWORD
46. sub WinMain(sys hInst,hPrevInst, asciiz* CmdLine, sys CmdShow)
47. '    LOCAL wc:WNDCLASSEX
48. '    LOCAL msg:MSG
49. '    LOCAL hwnd:HWND
50.    WNDCLASSEX wc
51.     MSG msg
52.     sys hwnd
53.    
54. '    mov   wc.cbSize, SIZEOF WNDCLASSEX
55.    wc.cbSize=SIZEOF WNDCLASSEX
56. '    mov   wc.style, CS_HREDRAW or CS_VREDRAW
57.    wc.style=CS_HREDRAW or CS_VREDRAW
58. '    mov   wc.lpfnWndProc, OFFSET WndProc
59.    wc.lpfnWndProc= @ WndProc
60. '    mov   wc.cbClsExtra, NULL
61.    wc.cbClsExtra= NULL
62. '    mov   wc.cbWndExtra, NULL
63.    wc.cbWndExtra= NULL
64. '    push  hInstance
65. '    pop   wc.hInstance
66.    wc.hInstance=hInstance
67. '    mov   wc.hbrBackground, COLOR_WINDOW+1
68.    wc.hbrBackground= COLOR_WINDOW+1
69. '    mov   wc.lpszMenuName, NULL
70.    wc.lpszMenuName= NULL
71. '    mov   wc.lpszClassName, OFFSET ClassName
72.    wc.lpszClassName= @ ClassName
73. '    invoke LoadIcon, NULL, IDI_APPLICATION
74. '    mov   wc.hIcon, eax
75.    wc.hIcon= LoadIcon NULL, IDI_APPLICATION
76. '    mov   wc.hIconSm, eax
77.    wc.hIconSm= LoadIcon NULL, IDI_APPLICATION
78. '    invoke LoadCursor, NULL, IDC_ARROW
79. '    mov   wc.hCursor, eax
80.    wc.hCursor= LoadCursor NULL, IDC_ARROW
81.  
82.  
83. '    invoke RegisterClassEx, addr wc
84.    if not RegisterClassEx @ wc then mbox "Registration failed" : end
85.    
86. '    INVOKE CreateWindowEx,NULL,ADDR ClassName,ADDR AppName,\
87. '           WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,\
88. '           CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,\
89. '           hInst,NULL
90. '    mov   hwnd, eax
91.    hwnd= CreateWindowEx NULL,@ ClassName,@ AppName,
92.            WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,
93.            CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,
94.            hInst,NULL
95.     if hwnd=NULL then mbox "CreateWindow failed" : end      
96.            
97. '    invoke ShowWindow, hwnd, SW_SHOWNORMAL
98.    ShowWindow hwnd, SW_SHOWNORMAL
99. '    invoke UpdateWindow, hwnd
100.    UpdateWindow hwnd
101.    
102. '   .WHILE TRUE
103. '        invoke GetMessage, ADDR msg, NULL, 0, 0
104. '        .BREAK .IF (!eax)
105. '        invoke TranslateMessage, ADDR msg
106. '        invoke DispatchMessage, ADDR msg
107. '    .ENDW
108.    while GetMessage @ msg, NULL, 0, 0
109.         TranslateMessage @ msg
110.         DispatchMessage @ msg
111.     wend
112.  
113. '    mov     eax,msg.wParam
114. '    ret
115. 'WinMain endp
116. end sub
117.  
118. 'WndProc proc hWnd:HWND, uMsg:UINT, wParam:WPARAM, lParam:LPARAM
119. function WndProc (sys hWnd, uint uMsg, sys wParam, lParam) as sys callback
120. '    .if uMsg==WM_DESTROY
121.    if uMsg=WM_DESTROY then
122. '        invoke PostQuitMessage, NULL
123.        PostQuitMessage NULL
124. '    .else
125.    else
126. '        invoke DefWindowProc, hWnd, uMsg, wParam, lParam        
127. '        ret
128.        return DefWindowProc hWnd, uMsg, wParam, lParam
129. '    .endif
130.    endif
131. '    xor eax,eax
132. '    ret
133. 'WndProc endp
134. end function
135.  
136. 'end start
137.  

[Arnold]

This is strange. I did not touch the tutorials since some time, because I did not understand much. And now it seems not to be so difficult.
In the code of Iczelion tutorial 5 I applied the first time the assembler statements of macro RGB and SelectObject which selects the handle of the logical font after CreateFont. The program works as expected, but is this really ok what I am doing?

Code: OxygenBasic

1. '.386
2. '.model flat,stdcall
3. 'option casemap:none
4.  
5. #compact
6.  
7. $ filename "Text.exe"
8. 'include "$inc/RTL32.inc"
9. include "$inc/minwin.inc"
10.  
11. % COLOR_WINDOW=5
12. % OUT_DEFAULT_PRECIS=0
13. % OEM_CHARSET=255
14.  
15. 'WinMain proto :DWORD,:DWORD,:DWORD,:DWORD
16. declare sub WinMain(sys hInst,hPrevInst, asciiz* CmdLine, sys CmdShow)
17.  
18. 'include \masm32\include\windows.inc
19. 'include \masm32\include\user32.inc
20. 'include \masm32\include\kernel32.inc
21. 'include \masm32\include\gdi32.inc
22. 'includelib \masm32\lib\user32.lib
23. 'includelib \masm32\lib\kernel32.lib
24. 'includelib \masm32\lib\gdi32.lib
25.  
26. macro RGB (red,green,blue)
27.         xor eax,eax
28.         mov ah,blue
29.         shl eax,8
30.         mov ah,green
31.         mov al,red
32. end macro
33.  
34. '.data
35. 'ClassName db "SimpleWinClass",0
36. 'AppName  db "Our First Window",0
37. 'TestString  db "Win32 assembly is great and easy!",0
38. 'FontName db "script",0
39. zstring ClassName = "SimpleWinClass"
40. zstring AppName  = "Our First Window"
41. zstring TestString  = "Win32 assembly is great and easy!"
42. zstring FontName = "script"
43.  
44. '.data?
45. 'hInstance HINSTANCE ?
46. 'CommandLine LPSTR ?
47. sys hInstance
48. asciiz ptr CommandLine
49.  
50. '.code
51. 'start:
52. '    invoke GetModuleHandle, NULL
53. '    mov    hInstance,eax
54. '    invoke GetCommandLine
55. '    mov CommandLine,eax
56. '    invoke WinMain, hInstance,NULL,CommandLine, SW_SHOWDEFAULT
57. '    invoke ExitProcess,eax
58. hInstance=GetModuleHandle NULL
59. &CommandLine=GetCommandLine
60. WinMain hInstance, NULL, CommandLine, SW_SHOWDEFAULT
61.  
62. 'WinMain proc hInst:HINSTANCE,hPrevInst:HINSTANCE,CmdLine:LPSTR,CmdShow:DWORD
63. sub WinMain(sys hInst,hPrevInst, asciiz* CmdLine, sys CmdShow)
64. '    LOCAL wc:WNDCLASSEX
65. '    LOCAL msg:MSG
66. '    LOCAL hwnd:HWND
67.    WNDCLASSEX wc
68.     MSG msg
69.     sys hwnd
70.  
71. '    mov   wc.cbSize,SIZEOF WNDCLASSEX
72. '    mov   wc.style, CS_HREDRAW or CS_VREDRAW
73. '    mov   wc.lpfnWndProc, OFFSET WndProc
74. '    mov   wc.cbClsExtra,NULL
75. '    mov   wc.cbWndExtra,NULL
76. '    push  hInst
77. '    pop   wc.hInstance
78. '    mov   wc.hbrBackground,COLOR_WINDOW+1
79. '    mov   wc.lpszMenuName,NULL
80. '    mov   wc.lpszClassName,OFFSET ClassName
81. '    invoke LoadIcon,NULL,IDI_APPLICATION
82. '    mov   wc.hIcon,eax
83. '    mov   wc.hIconSm,eax
84. '    invoke LoadCursor,NULL,IDC_ARROW
85. '    mov   wc.hCursor,eax
86.    wc.cbSize=SIZEOF WNDCLASSEX
87.     wc.style=CS_HREDRAW or CS_VREDRAW
88.     wc.lpfnWndProc= @WndProc
89.     wc.cbClsExtra= NULL
90.     wc.cbWndExtra= NULL
91.     wc.hInstance=hInstance
92.     wc.hbrBackground= COLOR_WINDOW+1
93.     wc.lpszMenuName= NULL
94.     wc.lpszClassName= @ClassName
95.     wc.hIcon= LoadIcon NULL, IDI_APPLICATION
96.     wc.hIconSm= LoadIcon NULL, IDI_APPLICATION
97.     wc.hCursor= LoadCursor NULL, IDC_ARROW
98.  
99. '    invoke RegisterClassEx, addr wc
100.    if not RegisterClassEx @wc then mbox "Registration failed" : end
101.    
102. '    INVOKE CreateWindowEx,NULL,ADDR ClassName,ADDR AppName,\
103. '           WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,\
104. '           CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,\
105. '           hInst,NULL
106. '    mov   hwnd,eax
107. '    INVOKE ShowWindow, hwnd,SW_SHOWNORMAL
108. '    INVOKE UpdateWindow, hwnd
109.    hwnd= CreateWindowEx NULL,@ClassName,@AppName,
110.            WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,
111.            CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,
112.            hInst,NULL
113.     if hwnd=NULL then mbox "CreateWindow failed" : end      
114.  
115.     ShowWindow hwnd, SW_SHOWNORMAL
116.     UpdateWindow hwnd
117.  
118. '    .WHILE TRUE
119. '                INVOKE GetMessage, ADDR msg,NULL,0,0
120. '                .BREAK .IF (!eax)
121. '                INVOKE TranslateMessage, ADDR msg
122. '                INVOKE DispatchMessage, ADDR msg
123. '    .ENDW
124. '    mov     eax,msg.wParam
125. '    ret
126.    while GetMessage @msg, NULL, 0, 0
127.         TranslateMessage @msg
128.         DispatchMessage @msg
129.     wend    
130. 'WinMain endp
131. end sub
132.  
133. 'WndProc proc hWnd:HWND, uMsg:UINT, wParam:WPARAM, lParam:LPARAM
134. function WndProc (sys hWnd, uint uMsg, sys wParam, lParam) as sys callback
135. '    LOCAL hdc:HDC
136. '    LOCAL ps:PAINTSTRUCT
137. '    LOCAL hfont:HFONT
138.    sys hdc
139.     PAINTSTRUCT ps
140.     sys hfont
141.  
142. '    .IF uMsg==WM_DESTROY
143. '        invoke PostQuitMessage,NULL
144. '    .ELSEIF uMsg==WM_PAINT
145. '        invoke BeginPaint,hWnd, ADDR ps
146. '        mov    hdc,eax
147. '        invoke CreateFont,24,16,0,0,400,0,0,0,OEM_CHARSET,\
148. '                            OUT_DEFAULT_PRECIS,CLIP_DEFAULT_PRECIS,\
149. '                            DEFAULT_QUALITY,DEFAULT_PITCH or FF_SCRIPT,\
150. '                            ADDR FontName
151. '        invoke SelectObject, hdc, eax
152. '        mov    hfont,eax
153. '        RGB    200,200,50
154. '        invoke SetTextColor,hdc,eax
155. '        RGB    0,0,255
156. '        invoke SetBkColor,hdc,eax
157. '        invoke TextOut,hdc,0,0,ADDR TestString,SIZEOF TestString
158. '        invoke SelectObject,hdc, hfont
159. '        invoke EndPaint,hWnd, ADDR ps
160. '        .ELSE
161. '        invoke DefWindowProc,hWnd,uMsg,wParam,lParam
162. '        ret
163. '    .ENDIF
164. '    xor    eax,eax
165. '    ret
166.    IF uMsg=WM_DESTROY then
167.         PostQuitMessage NULL
168.     ELSEIF uMsg=WM_PAINT then
169.         hdc=BeginPaint hWnd, @ps
170.         CreateFont 24,16,0,0,400,0,0,0,OEM_CHARSET,
171.                             OUT_DEFAULT_PRECIS,CLIP_DEFAULT_PRECIS,
172.                             DEFAULT_QUALITY,DEFAULT_PITCH or FF_SCRIPT,
173.                             @FontName
174.         SelectObject hdc, eax
175.         mov    hfont,eax
176.        
177.         RGB    200,200,50
178.         SetTextColor hdc,eax
179.         RGB    0,0,255
180.         SetBkColor hdc,eax
181.         TextOut hdc,0,0,@TestString,len TestString
182.         SelectObject hdc, hfont
183.         EndPaint hWnd, @ps
184.     ELSE
185.         return DefWindowProc hWnd,uMsg,wParam,lParam
186.     ENDIF
187.  
188. 'WndProc endp
189. end function
190.  
191. 'end start
192.  

[Arnold]

The more I deal with the Iczelion tutorials the more I am surprised that I had so many trouble the first time. In the meantime I arrived at tutorial 11-2.
Most of the tutorials need a resource file and this one will need to be linked with a resource file too. I used the version of Oxygenbasic of June 2017, provided at GitHub.
Although I did not use many assembly statements (it would not make sense to me) everything of the original tut11-2 can be found in the code.
If I did everything right then it seems to me that OxygenBasic is not only a powerful JIT compiler but can also handle inline assembly without problems.

Roland

Code: OxygenBasic

1. 'http://win32assembly.programminghorizon.com/tutorials.html
2. 'tut11-02
3.  
4. 'Must be compiled as exe file, using a resource file
5. 'can be done with MakeDialog.bat
6.  
7. #compact
8.  
9. $ filename "Dialog.exe"
10. include "$inc/RTL32.inc"
11. include "$inc/minwin.inc"
12.  
13. % COLOR_WINDOW=5
14.  
15. ' Additonal WinApi Functions
16. ! GetDlgItem lib "user32.dll" alias "GetDlgItem" (sys hDlg, nIDDlgItem) as sys
17. ! SetDlgItemText lib "user32.dll" alias"SetDlgItemTextA" (sys hDlg, int nIDDlgItem, char lpString) as bool
18.  
19. declare sub WinMain(sys hInst,hPrevInst, asciiz* CmdLine, sys CmdShow)
20. declare function DlgProc (sys hWnd, uint uMsg, sys wParam, lParam) as sys callback
21.  
22. zstring ClassName = "SimpleWinClass"
23. zstring AppName  = "Our Main Window"
24. zstring MenuName = "FirstMenu"
25. zstring DlgName = "MyDialog"
26. zstring TestString = "Hello, everybody"
27.  
28. sys hInstance
29. asciiz ptr CommandLine
30.  
31. % IDM_EXIT = 1
32. % IDM_ABOUT = 2
33. % IDC_EDIT  = 3000
34. % IDC_BUTTON = 3001
35. % IDC_EXIT = 3002
36.  
37. hInstance=GetModuleHandle NULL
38. &CommandLine=GetCommandLine
39. WinMain hInstance, NULL, CommandLine, SW_SHOWDEFAULT
40.  
41. sub WinMain(sys hInst,hPrevInst, asciiz* CmdLine, sys CmdShow)
42.     WNDCLASSEX wc
43.     MSG msg
44.     sys hwnd
45.  
46.     wc.cbSize=SIZEOF WNDCLASSEX
47.     wc.style= CS_HREDRAW or CS_VREDRAW
48.     wc.lpfnWndProc= @WndProc
49.     wc.cbClsExtra=NULL
50.     wc.cbWndExtra=NULL
51.     wc.hInstance=hInst
52.     wc.hbrBackground=COLOR_WINDOW+1
53.     wc.lpszMenuName= @MenuName
54.     wc.lpszClassName= @ClassName    
55.     wc.hIcon=LoadIcon NULL,IDI_APPLICATION
56.     wc.hIconSm=LoadIcon NULL,IDI_APPLICATION    
57.     wc.hCursor=LoadCursor NULL,IDC_ARROW
58.  
59.     if not RegisterClassEx @wc then mbox "Registration failed" : end
60.  
61.     hwnd= CreateWindowEx WS_EX_CLIENTEDGE,@ClassName,@AppName,
62.            WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,
63.            CW_USEDEFAULT,300,200,NULL,NULL,
64.            hInst,NULL
65.     if hwnd=NULL then mbox "CreateWindowEx failed" : end      
66.  
67.     ShowWindow hwnd, SW_SHOWNORMAL
68.     UpdateWindow hwnd
69.  
70.     while GetMessage @msg, NULL, 0, 0
71.          TranslateMessage @msg
72.          DispatchMessage @msg
73.     wend        
74. end sub
75.  
76. function WndProc (sys hWnd, uint uMsg, sys wParam, lParam) as sys callback
77.     IF uMsg=WM_DESTROY then
78.         PostQuitMessage NULL
79.     ELSEIF uMsg=WM_COMMAND then
80.         mov eax,wParam
81.         if ax=IDM_ABOUT then
82.             DialogBoxParam hInstance, @DlgName,hWnd, @DlgProc,NULL
83.         else
84.             DestroyWindow hWnd
85.         endif
86.     ELSE
87.         return DefWindowProc hWnd,uMsg,wParam,lParam
88.     ENDIF
89. end function
90.  
91. function DlgProc (sys hWnd, uint iMsg, sys wParam, lParam) as sys callback
92.     if iMsg=WM_INITDIALOG then
93.         GetDlgItem hWnd,IDC_EDIT
94.         SetFocus eax
95.     elseif iMsg=WM_CLOSE then
96.         EndDialog hWnd,NULL
97.     elseif iMsg=WM_COMMAND then
98.         mov eax,wParam
99.         mov edx,eax
100.         shr edx,16
101.         if dx=BN_CLICKED then
102.             mov eax,wParam  'otherwise will not work
103.            if eax=IDC_EXIT then
104.                 SendMessage hWnd,WM_CLOSE,NULL,NULL
105.             elseif eax=IDC_BUTTON then
106.                 SetDlgItemText hWnd,IDC_EDIT, @TestString
107.             endif
108.         endif
109.     else
110.         return FALSE
111.     endif
112.     return TRUE
113. end function
114.  

.

[Charles Pegge]

Hi Roland,

There was a clash between RTL32.inc and the bind statements in asm32\Winapi1.o2bas. I am testing out a solution but you can replace the bind statements entirely with extern lib declarations, or simply include MinWin.inc after RTL32.inc. It saves a lot of house-keeping.

This code originates from the very early formative time of OxygenBasic (July 2008!). Here is a modernised version using RTL32 and MinWin:

Code: [Select]

' Windows Hello World
' #2
' with winmain message loop and wndproc
' 12 July 2008
' 11:30 13/11/2017

' Charles Pegge


%    filename "t.exe"
uses rtl32
uses minwin

  var 4 cmdline,inst

  cmdline=GetCommandLine
  inst=GetModuleHandle 0
  call WinMain inst,0,cmdline,SW_NORMAL
  end
   

  o2 !10 ' align 16 bytes   
 
 
  '-------
  WinMain:
  '------- 
                    '
 

  push ebp
  mov ebp,esp
  'allocate stack space
  sub esp,100
  ' setup class data
  mov edi,esp
                     '
  def wclass     edi
  def style      [edi]
  def pWndproc   [edi+4]
  def cbClsExtra [edi+08]
  def cbWndExtra [edi+12]
  def hInstance  [edi+16]
  def icon       [edi+20]
  def cursor     [edi+24]
  def background [edi+28]
  def MenuName   [edi+32]
  def ClassName  [edi+36]
 
  ' window handle 
  def hWnd [edi+40]
   
  mov eax,CS_HREDRAW          '
  or  eax,CS_VREDRAW          '
  mov style,eax

  call fwd here : .here : pop eax : sub eax,here : add eax,WndProc
  mov pWndProc,eax

  mov  cbClsExtra,0   
  mov  cbWndExtra,0   
  mov  eax,[ebp+8]
  mov  hInstance,eax
  icon=LoadIcon 0, IDI_APPLICATION
  cursor=LoadCursor 0,IDC_ARROW
  background=GetStockObject WHITE_BRUSH '
  mov MenuName,0
  "HelloWin"
    mov ClassName,eax
    RegisterClass wclass
   
    (                           '
      cmp eax,0 : jnz exit                 '
      MessageBox 0,"Registration failed","Problem",MB_ICONERROR       '
      xor eax,eax              ' zero eax
      jmp long end_app         ' jmp xitwm
    )                          '


    hWnd=CreateWindowEx 0, ClassName,"Hello Window",
      WS_OVERLAPPEDWINDOW,
      CW_USEDEFAULT,CW_USEDEFAULT,640,480,
      0,0,hInstance,0
     
    (
      cmp eax,0 : jnz exit
      MessageBox 0,"Unable to create window","problem",MB_ICONERROR
      xor eax,eax             ' zero eax
      jmp long end_app          ' jmp xitwm
    )                           '
    ShowWindow hWnd,[ebp+20] ' show
    UpdateWindow hWnd


    '     MESSAGE LOOP          '
   
    add edi,40 ' place for wmsg struc
    (
      GetMessage edi,0,0,0        '
      cmp eax,0 : jz exit
      TranslateMessage edi
      DispatchMessage edi
      repeat
    )                      '
    mov eax,[edi+8]            ' Msg.wParam 3rd param
   
    end_app:
    ' deallocate stack space
    mov esp,ebp : pop ebp                 '
    ret 16
    ' end of WinMain


    type RECT
    (
    ' 16 bytes
    4  left
    4  top
    4  right
    4  bottom
    )

    type PAINTSTRUCT
    (
    ' 64 bytes
    4    hDC
    4    fErase
    rect rcPaint
    4    fRestore
    4    fIncUpdate
    32   rgbReserved
    )

    '-------   
    WndProc:
    '-------
    def hWnd   [ebp+08]
    def wMsg   [ebp+12]            '
    def wParam [ebp+16]            '
    def lParam [ebp+20]            '

    def WM_CREATE  1
    def WM_DESTROY 2
    def WM_PAINT   15
    def WM_CLOSE   16
    def WM_KEYDOWN 256
 
    push ebp : mov ebp,esp
    push ebx : push esi
    '
    'call _mem 'sets ebx address of bssdata
    addr ebx,bssdata
    '
    ' not using stack locals so no subractions for esp
   
            '
    mov eax,wMsg
    (
      (
        cmp eax, WM_CREATE : jnz exit
        xor eax,eax
        jmp long endselect
      )  ' end create
       
      (
        cmp eax, WM_DESTROY : jnz exit
        PostQuitMessage 0
        xor eax,eax
        jmp long endselect
      ) ' end destroy

      (
        cmp eax,WM_PAINT : jnz exit
        sub esp,100 ' extra workspace
        def cRect   [ebp-60]
        def hDC     [ebp-20]
        def Paintst  [ebp-100]
        '
        BeginPaint hWnd, @Paintst
        mov hDC,eax
        GetClientRect  hWnd, @cRect
          ' style
          ' 0x20 DT_SINGLELINE
          ' 0x04 DT_VCENTER
          ' 0x01 DT_CENTER
          ' 0x25
        DrawText hDC,"Hello World!",-1,@cRect,0x25
        EndPaint hWnd,@Paintst
        xor eax,eax
        jmp long endselect
      ) ' end paint
      (
        cmp eax,WM_KEYDOWN : jnz exit
        (
          mov eax,wParam
          cmp al,27 : jnz exit ' esc key
          PostMessage hWnd,WM_CLOSE,0,0
        )
        xor eax,eax  ' zero
        jmp long endselect
      ) ' end keydown
      ' case else
      DefWindowProc hWnd,wMsg,wParam,lParam
    ) ' end select
    endselect:
    '
    pop esi : pop ebx
    mov esp,ebp : pop ebp
    ret 16

The main problems with using Assembler as an alternative to Basic is 32bit/64bit compatability, and language granularity. OxygenBasic supports a form of structured Asm programming but most Assemblers require jumps to be done with labels (the original goto spaghetti programming )

You can make most lines of Basic reveal the underlying Asm by prefixing with #show. This is my main compiler debugging tool.

[Arnold]

Hi Charles,

thank you for the revised WinApi1 code. I was not sure if I asked a stupid question, but now I am glad that I asked. The structure of the code can be compared much better now with masm32. I suppose masm32 does many things in the background too. I will continue the Iczelion tutorials (they are very instructive for me) with the intention to use OxygenBasic's syntax and tools as much as possible and use assembly statements when they make some sense.

What is the effect of: addr ebx,bssdata ? I learned that the BSS segment holds data of uninitialized static and global variables, so I assume bssdata is handled internally by OxygenBasic?

Somewhere I read that Oxygen requires the ebx, ebp and esi registers, which can be saved/retrieved with pushad/popad. I assume some of the registers should not be used nevertheless after pushad?

Roland

[Charles Pegge]

Hi Roland,

All global/static variables and function vectors are addressed with the ebx register, and all local variables are similarly addressed using the ebp register. Therefore these registers should be preserved with care if your assembly code changes them.

To access global variables etc, the ebx register must hold the address of bssdata. It must be set for all extern/callback functions, such as wndproc. This is normally done internally by calling a low level procedure _mem, which does the same as addr ebx,bssdata.

[Arnold]

Hi Charles,

during my studies of the Iczelion tutorials I noticed an already forgotten discrepancy with constants using expressions:

'% WM_FINISH = WM_USER+0x100 '1280
'#define WM_FINISH WM_USER+100h '1280

'const WM_FINISH = WM_USER+0x100 '1280
sys WM_FINISH = WM_USER+0x100 '1280
print "WM_FINISH " WM_FINISH

The attached code of tut15 will work with const and sys and will not work correctly with % and #define neither with oxygen.dll provided at GitHub nor with the newer oxygen.dll in progress you provided some weeks ago. Will you get the same results and is there an explanation for the different behaviour? The problem occurs when using SendMessage with WM_FINISH.

Roland


.

[Charles Pegge]

Hi Roland,

%= precalculates the macro:
see if this makes a difference:

%= WM_FINISH = WM_USER+0x100 '1280

[Arnold]

Thank you, Charles. %= works fine. This is an excellent solution.

Roland

[Arnold]

Hi Charles,

in the meantime I finished Iczelion's tutorial 33 (I skipped over some lessons after tut19). The demo works quite nice and I am looking forward to the last two lessons.

I would like to ask a question about the WinApi function RtlZeroMemory (ZeroMemory):
   RtlZeroMemory @ofn,sizeof ofn   'OPENFILENAME structure

I think this can be done with:
   ofn={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}

Are there other possible ways to fill the structure with zeros?

Roland

[Charles Pegge]

Hi Roland,

Oxygen variables and memory blocks are already initialized with nulls when created, but if you need to clear a block specifically:

Code: [Select]

  macro FillBytes(name,count,value)
  =================================
  addr rsi,name
  mov rcx,count
  (
   dec rcx
   jl exit
   mov byte [rsi],value
   inc rsi
   repeat
  )
  end macro

With the o2 assembler, this will work for both 64 bit and 32 bit systems, and I will include it in generics.inc