1 /***************************************************************************
2  * Copyright (c) 2024 Microsoft Corporation
3  *
4  * This program and the accompanying materials are made available under the
5  * terms of the MIT License which is available at
6  * https://opensource.org/licenses/MIT.
7  *
8  * SPDX-License-Identifier: MIT
9  **************************************************************************/
10 
11 
12 /**************************************************************************/
13 /**************************************************************************/
14 /**                                                                       */
15 /** GUIX Component                                                        */
16 /**                                                                       */
17 /**   Canvas Management (Canvas)                                          */
18 /**                                                                       */
19 /**************************************************************************/
20 
21 #define GX_SOURCE_CODE
22 
23 
24 /* Include necessary system files.  */
25 
26 #include "gx_api.h"
27 #include "gx_system.h"
28 #include "gx_utility.h"
29 #include "gx_canvas.h"
30 
31 
32 /**************************************************************************/
33 /*                                                                        */
34 /*  FUNCTION                                               RELEASE        */
35 /*                                                                        */
36 /*    _gx_canvas_delete                                   PORTABLE C      */
37 /*                                                           6.1          */
38 /*  AUTHOR                                                                */
39 /*                                                                        */
40 /*    Kenneth Maxwell, Microsoft Corporation                              */
41 /*                                                                        */
42 /*  DESCRIPTION                                                           */
43 /*                                                                        */
44 /*    This function deletes a canvas.                                     */
45 /*                                                                        */
46 /*  INPUT                                                                 */
47 /*                                                                        */
48 /*    canvas                                Canvas control block          */
49 /*                                                                        */
50 /*  OUTPUT                                                                */
51 /*                                                                        */
52 /*    status                                Completion status             */
53 /*                                                                        */
54 /*  CALLS                                                                 */
55 /*                                                                        */
56 /*    memset                                Set control block and canvas  */
57 /*                                            memory to zero              */
58 /*                                                                        */
59 /*  CALLED BY                                                             */
60 /*                                                                        */
61 /*    Application Code                                                    */
62 /*                                                                        */
63 /*  RELEASE HISTORY                                                       */
64 /*                                                                        */
65 /*    DATE              NAME                      DESCRIPTION             */
66 /*                                                                        */
67 /*  05-19-2020     Kenneth Maxwell          Initial Version 6.0           */
68 /*  09-30-2020     Kenneth Maxwell          Modified comment(s),          */
69 /*                                            resulting in version 6.1    */
70 /*                                                                        */
71 /**************************************************************************/
_gx_canvas_delete(GX_CANVAS * canvas)72 UINT  _gx_canvas_delete(GX_CANVAS *canvas)
73 {
74     /* lock access to gx_system */
75 
76     GX_ENTER_CRITICAL
77 
78     if (_gx_system_canvas_created_count > 0)
79     {
80         if (canvas -> gx_canvas_created_previous)
81         {
82             canvas -> gx_canvas_created_previous -> gx_canvas_created_next = canvas -> gx_canvas_created_next;
83             if (canvas -> gx_canvas_created_next)
84             {
85                 canvas -> gx_canvas_created_next -> gx_canvas_created_previous = canvas -> gx_canvas_created_previous;
86             }
87         }
88         else
89         {
90             _gx_system_canvas_created_list = canvas -> gx_canvas_created_next;
91 
92             if (_gx_system_canvas_created_list)
93             {
94                 _gx_system_canvas_created_list -> gx_canvas_created_previous = GX_NULL;
95             }
96         }
97 
98         _gx_system_canvas_created_count--;
99 
100         /* Only for Win32, we sometimes have to create module 4 aligned scratch memory buffer */
101         #ifdef GX_TARGET_WIN32
102         if (canvas -> gx_canvas_padded_memory != GX_NULL)
103         {
104             free(canvas -> gx_canvas_padded_memory);
105         }
106         #endif
107 
108         /* Clear the screen control block.  */
109         memset(canvas, 0, sizeof(GX_CANVAS));
110     }
111     /* unlock gx_system.  */
112     GX_EXIT_CRITICAL
113 
114     /* Return successful status.  */
115     return(GX_SUCCESS);
116 }
117 
118