oldXMenu/XLookAssoc.c

   1 /* Copyright    Massachusetts Institute of Technology    1985   */
   2
   3 #include "copyright.h"
   4
   5 #include <config.h>
   6 #include <X11/Xlib.h>
   7 #include <X11/Xresource.h>
   8 #include "X10.h"
   9
  10 #ifndef NULL
  11 #define NULL 0
  12 #endif
  13
  14 /*
  15  * XLookUpAssoc - Retrieve the data stored in an XAssocTable by its XId.
  16  * If an appropriately matching XId can be found in the table the routine will
  17  * return apointer to the data associated with it. If the XId can not be found
  18  * in the table the routine will return a NULL pointer.  All XId's are relative
  19  * to the currently active Display.
  20  */
  21 caddr_t XLookUpAssoc(Display *dpy,
  22                      XAssocTable *table,  /* XAssocTable to search in. */
  23                      XID x_id)            /* XId to search for. */
  24 {
  25         int hash;
  26         register XAssoc *bucket;
  27         register XAssoc *Entry;
  28
  29         /* Hash the XId to get the bucket number. */
  30         hash = x_id & (table->size - 1);
  31         /* Look up the bucket to get the entries in that bucket. */
  32         bucket = &table->buckets[hash];
  33         /* Get the first entry in the bucket. */
  34         Entry = bucket->next;
  35
  36         /* Scan through the entries in the bucket for the right XId. */
  37         for (; Entry != bucket; Entry = Entry->next) {
  38                 if (Entry->x_id == x_id) {
  39                         /* We have the right XId. */
  40                         if (Entry->display == dpy) {
  41                                 /* We have the right display. */
  42                                 /* We have the right entry! */
  43                                 return(Entry->data);
  44                         }
  45                         /* Oops, identical XId's on different displays! */
  46                         continue;
  47                 }
  48                 if (Entry->x_id > x_id) {
  49                         /* We have gone past where it should be. */
  50                         /* It is apparently not in the table. */
  51                         return(NULL);
  52                 }
  53         }
  54         /* It is apparently not in the table. */
  55         return(NULL);
  56 }