src/common/bmalloc.c

/* Copyright (c) 1990 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "$SunId$ LBL";
#endif

/*
 * Basic memory allocation w/o overhead.
 * Calls malloc(3) for big requests.
 *
 */

#define  NULL           0

#ifndef  MBLKSIZ
#define  MBLKSIZ        16376           /* size of memory allocation block */
#endif
#define  WASTEFRAC      4               /* don't waste more than this */
#ifndef  ALIGN
#define  ALIGN          int             /* type for alignment */
#endif
#define  BYTES_WORD     sizeof(ALIGN)


char *
bmalloc(n)              /* allocate a block of n bytes, no refunds */
register unsigned  n;
{
        extern char  *malloc();
        static char  *bpos = NULL;
        static unsigned  nrem = 0;

        if (n > nrem && (n > MBLKSIZ || nrem > MBLKSIZ/WASTEFRAC))
                return(malloc(n));                      /* too big */

        n = (n+(BYTES_WORD-1))&~(BYTES_WORD-1);         /* word align */

        if (n > nrem) {
                if ((bpos = malloc((unsigned)MBLKSIZ)) == NULL) {
                        nrem = 0;
                        return(NULL);
                }
                nrem = MBLKSIZ;
        }
        bpos += n;
        nrem -= n;
        return(bpos - n);
}


bfree(p, n)                     /* free random memory */
char    *p;
unsigned        n;
{
        /* not implemented */
}
Revision:	1.2
Committed:	Tue Sep 25 19:37:15 1990 UTC (33 years, 7 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 1.1:	+8 -3 lines
Log Message:	improved test for deferring to malloc
#	User	Rev	Content
1	greg	1.1	/* Copyright (c) 1990 Regents of the University of California */
2
3			#ifndef lint
4			static char SCCSid[] = "$SunId$ LBL";
5			#endif
6
7			/*
8	greg	1.2	* Basic memory allocation w/o overhead.
9			* Calls malloc(3) for big requests.
10	greg	1.1	*
11			*/
12
13	greg	1.2	#define NULL 0
14
15	greg	1.1	#ifndef MBLKSIZ
16			#define MBLKSIZ 16376 /* size of memory allocation block */
17			#endif
18	greg	1.2	#define WASTEFRAC 4 /* don't waste more than this */
19	greg	1.1	#ifndef ALIGN
20			#define ALIGN int /* type for alignment */
21			#endif
22			#define BYTES_WORD sizeof(ALIGN)
23
24
25			char *
26			bmalloc(n) /* allocate a block of n bytes, no refunds */
27			register unsigned n;
28			{
29	greg	1.2	extern char *malloc();
30	greg	1.1	static char *bpos = NULL;
31			static unsigned nrem = 0;
32
33	greg	1.2	if (n > nrem && (n > MBLKSIZ \|\| nrem > MBLKSIZ/WASTEFRAC))
34			return(malloc(n)); /* too big */
35	greg	1.1
36			n = (n+(BYTES_WORD-1))&~(BYTES_WORD-1); /* word align */
37
38			if (n > nrem) {
39			if ((bpos = malloc((unsigned)MBLKSIZ)) == NULL) {
40			nrem = 0;
41			return(NULL);
42			}
43			nrem = MBLKSIZ;
44			}
45			bpos += n;
46			nrem -= n;
47			return(bpos - n);
48			}
49
50
51			bfree(p, n) /* free random memory */
52			char *p;
53			unsigned n;
54			{
55			/* not implemented */
56			}