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- /* $XConsortium: XCrAssoc.c,v 10.17 91/01/06 12:04:57 rws Exp $ */
- /* Copyright Massachusetts Institute of Technology 1985 */
-
- /*
- Permission to use, copy, modify, distribute, and sell this software and its
- documentation for any purpose is hereby granted without fee, provided that
- the above copyright notice appear in all copies and that both that
- copyright notice and this permission notice appear in supporting
- documentation, and that the name of M.I.T. not be used in advertising or
- publicity pertaining to distribution of the software without specific,
- written prior permission. M.I.T. makes no representations about the
- suitability of this software for any purpose. It is provided "as is"
- without express or implied warranty.
- */
-
- #include "X11/Xlib.h"
- #include "X10.h"
- #include "errno.h"
-
- #ifndef NULL
- #define NULL 0
- #endif
-
- extern int errno;
-
- /*
- * XCreateAssocTable - Create an XAssocTable. The size argument should be
- * a power of two for efficiency reasons. Some size suggestions: use 32
- * buckets per 100 objects; a reasonable maximum number of object per
- * buckets is 8. If there is an error creating the XAssocTable, a NULL
- * pointer is returned.
- */
- XAssocTable *XCreateAssocTable(size)
- register int size; /* Desired size of the table. */
- {
- register XAssocTable *table; /* XAssocTable to be initialized. */
- register XAssoc *buckets; /* Pointer to the first bucket in */
- /* the bucket array. */
-
- /* Malloc the XAssocTable. */
- if ((table = (XAssocTable *)malloc(sizeof(XAssocTable))) == NULL) {
- /* malloc call failed! */
- errno = ENOMEM;
- return(NULL);
- }
-
- /* malloc the buckets (actually just their headers). */
- buckets = (XAssoc *)calloc((unsigned)size, (unsigned)sizeof(XAssoc));
- if (buckets == NULL) {
- /* calloc call failed! */
- errno = ENOMEM;
- return(NULL);
- }
-
- /* Insert table data into the XAssocTable structure. */
- table->buckets = buckets;
- table->size = size;
-
- while (--size >= 0) {
- /* Initialize each bucket. */
- buckets->prev = buckets;
- buckets->next = buckets;
- buckets++;
- }
-
- return(table);
- }
-