workbench/libs/kms/openkeymap.c

   1 #include <libraries/kms.h>
   2 #include <proto/dos.h>
   3 #include <proto/exec.h>
   4
   5 #include <string.h>
   6
   7 #include "kms_intern.h"
   8
   9 /*****************************************************************************
  10
  11     NAME */
  12 #include <proto/kms.h>
  13
  14         AROS_LH1(struct KeyMapNode *, OpenKeymap,
  15
  16 /*  SYNOPSIS */
  17         AROS_LHA(STRPTR, name, A0),
  18
  19 /*  LOCATION */
  20         struct KMSLibrary *, KMSBase, 5, Kms)
  21
  22 /*  FUNCTION
  23         Open a keymap by name.
  24
  25     INPUTS
  26         name - Keymap name. Can be a full pathname or just a name.
  27                In the latter case DEVS:Keymaps is assumed to be a
  28                path to the file.
  29
  30     RESULT
  31         A pointer to the loaded keymap.
  32
  33     NOTES
  34         This function automatically keeps track of loaded keymaps
  35         via keymap.resource. No more than a single copy of the keymap
  36         will be loaded.
  37
  38     EXAMPLE
  39
  40     BUGS
  41
  42     SEE ALSO
  43
  44     INTERNALS
  45
  46     HISTORY
  47
  48 *****************************************************************************/
  49 {
  50     AROS_LIBFUNC_INIT
  51
  52     struct KeyMapNode *kmn, *kmn2;
  53     ULONG buflen = 0;
  54     STRPTR km_name;
  55     BPTR km_seg;
  56     struct KeyMapResource *kmr = ((struct kms_base *)KMSBase)->kmr;
  57
  58     km_name  = FilePart(name);
  59     if (km_name == name)
  60     {
  61         /*
  62          * A short name was given.
  63          * Check if the keymap is already resident.
  64          * Unfortunately we still have to use Forbid()/Permit() locking
  65          * because there can be lots of software which does the same.
  66          * AmigaOS(tm) never provided a centralized semaphore for this.
  67          */
  68         Forbid();
  69         kmn = (struct KeyMapNode *)FindName(&kmr->kr_List, name);
  70         Permit();
  71
  72         /* If found, return it */
  73         if (kmn)
  74             return kmn;
  75
  76         /* Prepend DEVS:Keymaps to the supplied name */
  77         buflen = strlen(name) + PREFIX_LEN;
  78         name = AllocMem(buflen, MEMF_ANY);
  79         if (!name)
  80             return NULL;
  81
  82         strcpy(name, PREFIX_STR);
  83         AddPart(name, km_name, buflen);
  84     }
  85
  86     /*
  87      * Currently keymaps are still loaded using LoadSeg().
  88      * In future we can extend this. For example we can add
  89      * support for AmigaOS4(tm)-compatible keymaps which are plain text files.
  90      * ELF keymaps have one strong disadvantage: they are CPU-dependent.
  91      */
  92     km_seg = LoadSeg(name);
  93     if (buflen)
  94         FreeMem(name, buflen);
  95
  96     if (!km_seg)
  97         return NULL;
  98
  99     kmn = BADDR(km_seg) + sizeof(APTR);
 100
 101     Forbid();
 102
 103     /*
 104      * Check if this keymap is already loaded once more before installing it.
 105      * Now use name contained in the KeyMapNode instead of user-supplied one.
 106      * This is needed for two cases:
 107      * 1. Several programs running concurrently tried to load and install
 108      *    the same keymap (rare but theoretically possible case).
 109      * 2. We are given full file path. We need to load the file and take
 110      *    keymap name from it.
 111      */
 112     kmn2 = (struct KeyMapNode *)FindName(&kmr->kr_List, kmn->kn_Node.ln_Name);
 113     if (!kmn2)
 114         Enqueue(&kmr->kr_List, &kmn->kn_Node);
 115
 116     Permit();
 117
 118     /* If the keymap was already loaded, use the resident copy and drop our one */
 119     if (kmn2)
 120     {
 121         UnLoadSeg(km_seg);
 122         kmn = kmn2;
 123     }
 124
 125     return kmn;
 126
 127     AROS_LIBFUNC_EXIT
 128 }