oldXMenu/XCrAssoc.c

   1 /* Copyright    Massachusetts Institute of Technology    1985   */
   2 /* Copyright (C) 2001, 2002, 2003, 2004, 2005,
   3                  2006, 2007 Free Software Foundation, Inc.  */
   4
   5 #include "copyright.h"
   6
   7
   8 #include <config.h>
   9 #include <X11/Xlib.h>
  10 #include <errno.h>
  11 #include "X10.h"
  12
  13 #ifndef NULL
  14 #define NULL 0
  15 #endif
  16
  17 extern int errno;
  18
  19 /*
  20  * XCreateAssocTable - Create an XAssocTable.  The size argument should be
  21  * a power of two for efficiency reasons.  Some size suggestions: use 32
  22  * buckets per 100 objects;  a reasonable maximum number of object per
  23  * buckets is 8.  If there is an error creating the XAssocTable, a NULL
  24  * pointer is returned.
  25  */
  26 XAssocTable *XCreateAssocTable(size)
  27         register int size;              /* Desired size of the table. */
  28 {
  29         register XAssocTable *table;    /* XAssocTable to be initialized. */
  30         register XAssoc *buckets;       /* Pointer to the first bucket in */
  31                                         /* the bucket array. */
  32
  33         /* Malloc the XAssocTable. */
  34         if ((table = (XAssocTable *)malloc(sizeof(XAssocTable))) == NULL) {
  35                 /* malloc call failed! */
  36                 errno = ENOMEM;
  37                 return(NULL);
  38         }
  39
  40         /* calloc the buckets (actually just their headers). */
  41         buckets = (XAssoc *)calloc((unsigned)size, (unsigned)sizeof(XAssoc));
  42         if (buckets == NULL) {
  43                 /* calloc call failed! */
  44                 errno = ENOMEM;
  45                 return(NULL);
  46         }
  47
  48         /* Insert table data into the XAssocTable structure. */
  49         table->buckets = buckets;
  50         table->size = size;
  51
  52         while (--size >= 0) {
  53                 /* Initialize each bucket. */
  54                 buckets->prev = buckets;
  55                 buckets->next = buckets;
  56                 buckets++;
  57         }
  58
  59         return(table);
  60 }
  61
  62 /* arch-tag: 5df3237d-ada0-4345-a3ab-282cafb397aa
  63    (do not change this comment) */