rom/intuition/lockpubscreen.c

   1 /*
   2     Copyright  1995-2010, The AROS Development Team. All rights reserved.
   3     Copyright  2001-2003, The MorphOS Development Team. All Rights Reserved.
   4     $Id$
   5 */
   6
   7 #include <string.h>
   8 #include "intuition_intern.h"
   9
  10 static struct PubScreenNode *findcasename(struct List *list, const UBYTE *name);
  11
  12 /*****************************************************************************
  13
  14     NAME */
  15 #include <proto/intuition.h>
  16
  17     AROS_LH1(struct Screen *, LockPubScreen,
  18
  19 /*  SYNOPSIS */
  20          AROS_LHA(CONST_STRPTR, name, A0),
  21
  22 /*  LOCATION */
  23          struct IntuitionBase *, IntuitionBase, 85, Intuition)
  24
  25 /*  FUNCTION
  26
  27     Locks a public screen, thus preventing it from closing.
  28     This is useful if you want to put up a visitor window on a public screen
  29     and need to check some of the public screen's field first -- not locking
  30     the screen may lead to the public screen not existing when your visitor
  31     window is ready.
  32
  33     If you try to lock the Workbench screen or the default public screen
  34     and there isn't any, the Workbench screen will be automatically opened
  35     and locked.
  36
  37     INPUTS
  38
  39     Name   --  Name of the public screen or NULL for the default public
  40                screen. The name "Workbench" refers to the Workbench screen.
  41                The name is case insensitive.
  42
  43     RESULT
  44
  45     A pointer to the screen or NULL if something went wrong. Failure can
  46     happen for instance when the public screen is in private state or doesn't
  47     exist.
  48
  49     NOTES
  50
  51     You don't need to hold the lock when your visitor window is opened as
  52     the pubscreen cannot be closed as long as there are visitor windows
  53     on it.
  54
  55     EXAMPLE
  56
  57     To open a visitor window which needs information from the screen structure
  58     of the public screen to open on, do this:
  59
  60     if((pubscreen = LockPubScreen("PubScreentoOpenon")) != NULL)
  61     {
  62         ...check pubscreen's internal data...
  63     OpenWindow(VisitorWindow, pubscreen);
  64     UnlockPubScreen(NULL, pubscreen);
  65     ...use your visitor window...
  66     CloseWindow(VisitorWindow);
  67     }
  68
  69     BUGS
  70
  71     SEE ALSO
  72
  73     OpenWindow(), UnlockPubScreen(), GetScreenData()
  74
  75     INTERNALS
  76
  77     HISTORY
  78     29-10-95    digulla automatically created from
  79                 intuition_lib.fd and clib/intuition_protos.h
  80
  81 *****************************************************************************/
  82 {
  83     AROS_LIBFUNC_INIT
  84
  85     struct Screen *screen = NULL;
  86     struct List   *list;
  87
  88     DEBUG_LOCKPUBSCREEN(dprintf("LockPubScreen: name <%s>\n",
  89                                 name ? name : (CONST_STRPTR)"NULL"));
  90     DEBUG_LOCKPUBSCREEN(dprintf("LockPubScreen: task %p <%s>\n",
  91                                 SysBase->ThisTask,
  92                                 SysBase->ThisTask->tc_Node.ln_Name ? SysBase->ThisTask->tc_Node.ln_Name : "NULL"));
  93
  94     list = LockPubScreenList();
  95
  96     if( !name )
  97     {
  98
  99         screen = GetPrivIBase(IntuitionBase)->DefaultPubScreen;
 100
 101         /* If IntuitionBase->DefaultPubScreen is NULL, then Workbench screen
 102            is default public screen. But note that, Workbench screen might
 103            here not be open either. */
 104
 105         if (!screen) screen = GetPrivIBase(IntuitionBase)->WorkBench;
 106
 107         if (screen)
 108         {
 109             ASSERT_VALID_PTR(screen);
 110             GetPrivScreen(screen)->pubScrNode->psn_VisitorCount++;
 111             DEBUG_VISITOR(dprintf("LockPubScreen: 1 screen %p count %ld Task <%s>\n",
 112                                   screen, GetPrivScreen(screen)->pubScrNode->psn_VisitorCount,
 113                                   FindTask(NULL)->tc_Node.ln_Name));
 114             DEBUG_LOCKPUBSCREEN(dprintf("LockPubScreen: screen %p count %d\n",
 115                                         screen, GetPrivScreen(screen)->pubScrNode->psn_VisitorCount));
 116         }
 117
 118     }
 119     else
 120     {
 121         struct PubScreenNode *psn;
 122
 123         ASSERT_VALID_PTR(name);
 124
 125         /* Browse the public screen list */
 126         if( (psn = findcasename(list, (UBYTE *)name )) )
 127         {
 128             ASSERT_VALID_PTR(psn);
 129
 130             /* Don't lock screens in private state */
 131             if( (psn != NULL) && !(psn->psn_Flags & PSNF_PRIVATE) )
 132             {
 133                 /* Increment screen lock count */
 134                 psn->psn_VisitorCount++;
 135                 screen = psn->psn_Screen;
 136                 DEBUG_VISITOR(dprintf("LockPubScreen: 2 node %p screen %p count %ld <%s>\n",
 137                                       psn, screen, psn->psn_VisitorCount,
 138                                       FindTask(NULL)->tc_Node.ln_Name));
 139                 DEBUG_LOCKPUBSCREEN(dprintf("LockPubScreen: node %p screen %p count %d\n",
 140                                             psn, screen, psn->psn_VisitorCount));
 141                 ASSERT_VALID_PTR(screen);
 142             }
 143         }
 144
 145     }
 146
 147     UnlockPubScreenList();
 148
 149     /* If no screen was found and the requested one was the Workbench screen or
 150      * the default public screen, open the Workbench screen and lock it. */
 151     if( (screen == NULL) && ((name == NULL) || (strcasecmp( name, "Workbench" ) == 0)) )
 152     {
 153         OpenWorkBench();
 154         DEBUG_LOCKPUBSCREEN(dprintf("LockPubScreen: opened workbench\n"));
 155
 156         LockPubScreenList();
 157
 158         screen = GetPrivIBase(IntuitionBase)->WorkBench;
 159         if (!screen)
 160         {
 161             struct PubScreenNode *psn;
 162
 163             /* Maybe something patched OpenWorkbench, and there is a 'Workbench'
 164              * screen in the list. Our private pointer is just not set. */
 165             if( (psn = findcasename(list, "Workbench" )) )
 166             {
 167                 /* Don't lock screens in private state */
 168                 if( (psn != NULL) && !(psn->psn_Flags & PSNF_PRIVATE) )
 169                     screen = psn->psn_Screen;
 170             }
 171         }
 172
 173         if( screen )
 174         {
 175             ASSERT_VALID_PTR(screen);
 176             GetPrivScreen(screen)->pubScrNode->psn_VisitorCount++;
 177             DEBUG_VISITOR(dprintf("LockPubScreen: 3 screen %p count %d <%s>\n",
 178                                   screen, GetPrivScreen(screen)->pubScrNode->psn_VisitorCount,
 179                                   FindTask(NULL)->tc_Node.ln_Name));
 180
 181             DEBUG_LOCKPUBSCREEN(dprintf("LockPubScreen: screen %p count %d\n",
 182                                         screen, GetPrivScreen(screen)->pubScrNode->psn_VisitorCount));
 183         }
 184
 185         UnlockPubScreenList();
 186     }
 187
 188     FireScreenNotifyMessage((IPTR) screen, SNOTIFY_LOCKPUBSCREEN, IntuitionBase);
 189
 190     DEBUG_LOCKPUBSCREEN(dprintf("LockPubScreen: return %p\n", screen));
 191
 192     return screen;
 193
 194     AROS_LIBFUNC_EXIT
 195 } /* LockPubScreen */
 196
 197
 198 /* case insensitive FindName() */
 199 static struct PubScreenNode *findcasename(struct List *list, const UBYTE *name)
 200 {
 201     struct Node *node;
 202
 203     for (node = GetHead(list); node; node = GetSucc(node))
 204     {
 205         if(node->ln_Name)
 206         {
 207             if (!strcasecmp (node->ln_Name, name))
 208                 break;
 209         }
 210     }
 211     return (struct PubScreenNode *)node;
 212 }