4.3BSD - /usr/src/new/X/Xlib/XLookUpAssoc.c

   1: #include <X/mit-copyright.h>
   2: 
   3: /* $Header: XLookUpAssoc.c,v 10.4 86/02/01 15:36:21 tony Rel $ */
   4: /* Copyright    Massachusetts Institute of Technology    1985	*/
   5: 
   6: #include "XlibInternal.h"
   7: 
   8: /*
   9:  * XLookUpAssoc - Retrieve the data stored in an XAssocTable by its XId.
  10:  * If an appropriately matching XId can be found in the table the routine will
  11:  * return apointer to the data associated with it. If the XId can not be found
  12:  * in the table the routine will return a NULL pointer.  All XId's are relative
  13:  * to the currently active Display.
  14:  */
  15: caddr_t XLookUpAssoc(table, x_id)
  16:     register XAssocTable *table;    /* XAssocTable to search in. */
  17:     register XId x_id;          /* XId to search for. */
  18: {
  19:     int hash;
  20:     register XAssoc *bucket;
  21:     register XAssoc *entry;
  22: 
  23:     /* Hash the XId to get the bucket number. */
  24:     hash = x_id & (table->size - 1);
  25:     /* Look up the bucket to get the entries in that bucket. */
  26:     bucket = &(*table->table)[hash];
  27:     /* Get the first entry in the bucket. */
  28:     entry = bucket->next;
  29: 
  30:     /* Scan through the entries in the bucket for the right XId. */
  31:     for (entry; entry != bucket; entry = entry->next) {
  32:         if (entry->x_id == x_id) {
  33:             /* We have the right XId. */
  34:             if (entry->display == _XlibCurrentDisplay) {
  35:                 /* We have the right display. */
  36:                 /* We have the right entry! */
  37:                 return(entry->data);
  38:             }
  39:             /* Oops, identical XId's on different displays! */
  40:             continue;
  41:         }
  42:         if (entry->x_id > x_id) {
  43:             /* We have gone past where it should be. */
  44:             /* It is apparently not in the table. */
  45:             return(NULL);
  46:         }
  47:     }
  48:     /* It is apparently not in the table. */
  49:     return(NULL);
  50: }

Defined functions