rom/misc/allocmiscresource.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: AllocMiscResource() function.
   6     Lang: English
   7 */
   8 #include "misc_intern.h"
   9 #include <proto/exec.h>
  10 #include <resources/misc.h>
  11
  12 /*****************************************************************************
  13
  14     NAME */
  15
  16         AROS_LH2(char *, AllocMiscResource,
  17
  18 /*  SYNOPSIS */
  19                  AROS_LHA(ULONG,  unitNum, d0),
  20                  AROS_LHA(char *, name,    a0),
  21
  22 /*  LOCATION */
  23                  APTR, MiscBase, 1, Misc)
  24
  25 /*  FUNCTION
  26
  27     Allocates one of the miscellaneous resources.
  28
  29     INPUTS
  30
  31     unitNum  --  The resource to allocate
  32     name     --  An identifying name for you, must NOT be NULL.
  33
  34     RESULT
  35
  36     NULL if the allocation was successful. If the resource couln't be
  37     allocated, the name of the holder of the resource is returned.
  38
  39     NOTES
  40
  41     EXAMPLE
  42
  43     BUGS
  44
  45     SEE ALSO
  46
  47     FreeMiscResource()
  48
  49     INTERNALS
  50
  51     The misc.resource should probably just redirect commands to a HIDD
  52     in the future, to support things like multiple serial ports.
  53
  54     HISTORY
  55
  56 *****************************************************************************/
  57 {
  58     AROS_LIBFUNC_INIT
  59
  60     char *errorStr = "Error -- invalid unit.";
  61     char *retval;
  62
  63     if(unitNum >= MR_MAXUNIT)
  64         return errorStr;
  65
  66     ObtainSemaphore(&GPB(MiscBase)->mb_Lock);
  67
  68     retval = GPB(MiscBase)->mb_owners[unitNum];
  69
  70     if(retval == NULL)
  71         GPB(MiscBase)->mb_owners[unitNum] = name;
  72
  73     ReleaseSemaphore(&GPB(MiscBase)->mb_Lock);
  74
  75     return retval;
  76
  77     AROS_LIBFUNC_EXIT
  78 } /* AllocMiscResource */