Return to XMakeAssoc.c CVS log

Up to [Apple XNU] / GNUtools / emacs / oldXMenu

Annotation of GNUtools/emacs/oldXMenu/XMakeAssoc.c, revision 1.1.1.1

1.1       root        1: /* $XConsortium: XMakeAssoc.c,v 10.18 91/01/06 12:09:28 rws Exp $ */
                      2: /* Copyright    Massachusetts Institute of Technology    1985  */
                      3: 
                      4: /*
                      5: Permission to use, copy, modify, distribute, and sell this software and its
                      6: documentation for any purpose is hereby granted without fee, provided that
                      7: the above copyright notice appear in all copies and that both that
                      8: copyright notice and this permission notice appear in supporting
                      9: documentation, and that the name of M.I.T. not be used in advertising or
                     10: publicity pertaining to distribution of the software without specific,
                     11: written prior permission.  M.I.T. makes no representations about the
                     12: suitability of this software for any purpose.  It is provided "as is"
                     13: without express or implied warranty.
                     14: */
                     15: 
                     16: #include "X11/Xlib.h"
                     17: #include "X10.h"
                     18: #include <errno.h>
                     19: 
                     20: #ifndef NULL
                     21: #define NULL 0
                     22: #endif
                     23: 
                     24: extern int errno;
                     25: 
                     26: extern int (*_XIOErrorFunction)();     /* X system error reporting routine. */
                     27: 
                     28: void insque();
                     29: struct qelem {
                     30:        struct    qelem *q_forw;
                     31:        struct    qelem *q_back;
                     32:        char q_data[1];
                     33: };
                     34: /*
                     35:  * XMakeAssoc - Insert data into an XAssocTable keyed on an XId.
                     36:  * Data is inserted into the table only once.  Redundant inserts are
                     37:  * meaningless (but cause no problems).  The queue in each association
                     38:  * bucket is sorted (lowest XId to highest XId).
                     39:  */
                     40: XMakeAssoc(dpy, table, x_id, data)
                     41:        register Display *dpy;
                     42:        register XAssocTable *table;
                     43:        register XID x_id;
                     44:        register caddr_t data;
                     45: {
                     46:        int hash;
                     47:        register XAssoc *bucket;
                     48:        register XAssoc *Entry;
                     49:        register XAssoc *new_entry;
                     50:        
                     51:        /* Hash the XId to get the bucket number. */
                     52:        hash = x_id & (table->size - 1);
                     53:        /* Look up the bucket to get the entries in that bucket. */
                     54:        bucket = &table->buckets[hash];
                     55:        /* Get the first entry in the bucket. */
                     56:        Entry = bucket->next;
                     57: 
                     58:        /* If (Entry != bucket), the bucket is empty so make */
                     59:        /* the new entry the first entry in the bucket. */
                     60:        /* if (Entry == bucket), the we have to search the */
                     61:        /* bucket. */
                     62:        if (Entry != bucket) {
                     63:                /* The bucket isn't empty, begin searching. */
                     64:                /* If we leave the for loop then we have either passed */
                     65:                /* where the entry should be or hit the end of the bucket. */
                     66:                /* In either case we should then insert the new entry */
                     67:                /* before the current value of "Entry". */
                     68:                for (; Entry != bucket; Entry = Entry->next) {
                     69:                        if (Entry->x_id == x_id) {
                     70:                                /* Entry has the same XId... */
                     71:                                if (Entry->display == dpy) {
                     72:                                        /* Entry has the same Display... */
                     73:                                        /* Therefore there is already an */
                     74:                                        /* entry with this XId and Display, */
                     75:                                        /* reset its data value and return. */
                     76:                                        Entry->data = data;
                     77:                                        return;
                     78:                                }
                     79:                                /* We found an association with the right */
                     80:                                /* id but the wrong display! */
                     81:                                continue;
                     82:                        }
                     83:                        /* If the current entry's XId is greater than the */
                     84:                        /* XId of the entry to be inserted then we have */
                     85:                        /* passed the location where the new XId should */
                     86:                        /* be inserted. */
                     87:                        if (Entry->x_id > x_id) break;
                     88:                }
                     89:         }
                     90: 
                     91:        /* If we are here then the new entry should be inserted just */
                     92:        /* before the current value of "Entry". */
                     93:        /* Create a new XAssoc and load it with new provided data. */
                     94:        new_entry = (XAssoc *) malloc(sizeof(XAssoc));
                     95:        if (new_entry == NULL) {
                     96:                /* Malloc failed! */
                     97:                errno = ENOMEM;
                     98:                (*_XIOErrorFunction)(dpy);
                     99:        }
                    100:        new_entry->display = dpy;
                    101:        new_entry->x_id = x_id;
                    102:        new_entry->data = data;
                    103: 
                    104:        /* Insert the new entry. */
                    105:        insque((struct qelem *)new_entry, (struct qelem *)Entry->prev);
                    106: }
                    107: 

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.