root/trunk/oldXMenu/XMakeAssoc.c

/* Copyright    Massachusetts Institute of Technology    1985   */

#include "copyright.h"


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

#ifndef NULL
#define NULL 0
#endif

extern int errno;

void emacs_insque();
struct qelem {
        struct    qelem *q_forw;
        struct    qelem *q_back;
        char q_data[1];
};
/*
 * XMakeAssoc - Insert data into an XAssocTable keyed on an XId.
 * Data is inserted into the table only once.  Redundant inserts are
 * meaningless (but cause no problems).  The queue in each association
 * bucket is sorted (lowest XId to highest XId).
 */
XMakeAssoc(dpy, table, x_id, data)
        register Display *dpy;
        register XAssocTable *table;
        register XID x_id;
        register caddr_t data;
{
        int hash;
        register XAssoc *bucket;
        register XAssoc *Entry;
        register XAssoc *new_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;

        /* If (Entry != bucket), the bucket is empty so make */
        /* the new entry the first entry in the bucket. */
        /* if (Entry == bucket), the we have to search the */
        /* bucket. */
        if (Entry != bucket) {
                /* The bucket isn't empty, begin searching. */
                /* If we leave the for loop then we have either passed */
                /* where the entry should be or hit the end of the bucket. */
                /* In either case we should then insert the new entry */
                /* before the current value of "Entry". */
                for (; Entry != bucket; Entry = Entry->next) {
                        if (Entry->x_id == x_id) {
                                /* Entry has the same XId... */
                                if (Entry->display == dpy) {
                                        /* Entry has the same Display... */
                                        /* Therefore there is already an */
                                        /* entry with this XId and Display, */
                                        /* reset its data value and return. */
                                        Entry->data = data;
                                        return;
                                }
                                /* We found an association with the right */
                                /* id but the wrong display! */
                                continue;
                        }
                        /* If the current entry's XId is greater than the */
                        /* XId of the entry to be inserted then we have */
                        /* passed the location where the new XId should */
                        /* be inserted. */
                        if (Entry->x_id > x_id) break;
                }
        }

        /* If we are here then the new entry should be inserted just */
        /* before the current value of "Entry". */
        /* Create a new XAssoc and load it with new provided data. */
        new_entry = (XAssoc *) malloc(sizeof(XAssoc));
        new_entry->display = dpy;
        new_entry->x_id = x_id;
        new_entry->data = data;

        /* Insert the new entry. */
        emacs_insque((struct qelem *)new_entry, (struct qelem *)Entry->prev);
}

/* arch-tag: d7e3fb8a-f3b3-4c5d-a307-75ca67ec1b49
   (do not change this comment) */