root/trunk/oldXMenu/XLookAssoc.c

/* Copyright    Massachusetts Institute of Technology    1985   */

#include "copyright.h"


#include <X11/Xlib.h>
#include <X11/Xresource.h>
#include "X10.h"

#ifndef NULL
#define NULL 0
#endif

/*
 * XLookUpAssoc - Retrieve the data stored in an XAssocTable by its XId.
 * If an appropriately matching XId can be found in the table the routine will
 * return apointer to the data associated with it. If the XId can not be found
 * in the table the routine will return a NULL pointer.  All XId's are relative
 * to the currently active Display.
 */
caddr_t XLookUpAssoc(dpy, table, x_id)
        register Display *dpy;
        register XAssocTable *table;    /* XAssocTable to search in. */
        register XID x_id;                      /* XId to search for. */
{
        int hash;
        register XAssoc *bucket;
        register XAssoc *Entry;

        /* Hash the XId to get the bucket number. */
        hash = x_id & (table->size - 1);
        /* Look up the bucket to get the entries in that bucket. */
        bucket = &table->buckets[hash];
        /* Get the first entry in the bucket. */
        Entry = bucket->next;

        /* Scan through the entries in the bucket for the right XId. */
        for (; Entry != bucket; Entry = Entry->next) {
                if (Entry->x_id == x_id) {
                        /* We have the right XId. */
                        if (Entry->display == dpy) {
                                /* We have the right display. */
                                /* We have the right entry! */
                                return(Entry->data);
                        }
                        /* Oops, identical XId's on different displays! */
                        continue;
                }
                if (Entry->x_id > x_id) {
                        /* We have gone past where it should be. */
                        /* It is apparently not in the table. */
                        return(NULL);
                }
        }
        /* It is apparently not in the table. */
        return(NULL);
}

/* arch-tag: d5075d0c-4b71-467d-b33c-3f5c4c4afcf2
   (do not change this comment) */