Intial revision

lang/cem/libcc.ansi/stdlib/malloc/phys.h

@@ -0,0 +1,76 @@
+/* $Header$ */
+/*
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
+ */
+/*	Algorithms to manipulate the doubly-linked list of physical
+	chunks.
+*/
+publicdata mallink *ml_last;
+
+#define FREE_BIT		01
+#ifdef STORE
+#define STORE_BIT		02
+#define BITS			(FREE_BIT|STORE_BIT)
+#else
+#define BITS			(FREE_BIT)
+#endif
+
+#define __bits(ml)		((size_type)_phys_prev_of(ml) & BITS)
+#define	__free_of(ml)		((size_type)_phys_prev_of(ml) & FREE_BIT)
+#define __phys_prev_of(ml)	(mallink *)((size_type)_phys_prev_of(ml) & ~FREE_BIT)
+#define prev_size_of(ml)	((char *)(ml) - \
+				 (char *)__phys_prev_of(ml) - \
+				 mallink_size() \
+				)
+#define	set_phys_prev(ml,e) \
+	(_phys_prev_of(ml) = (mallink *) ((char *)e + __free_of(ml)))
+
+#ifdef	CHECK
+public Error(const char *fmt, const char *s, mallinkl *ml);
+#define	phys_prev_of(ml)	(mallink *) \
+	(first_mallink(ml) ? \
+		(char *)Error("phys_prev_of first_mallink %ld", "somewhere", ml) : \
+		(char *)__phys_prev_of(ml) \
+	)
+#else	/* ndef	CHECK */
+#define	phys_prev_of(ml)	__phys_prev_of(ml)
+#endif	/* CHECK */
+
+#define	first_mallink(ml)	(int) (__phys_prev_of(ml) == 0)
+#define	last_mallink(ml)	(int) ((ml) == ml_last)
+
+/*	There is an ambiguity in the semantics of phys_next_of: sometimes
+	one wants it to return MAL_NULL if there is no next chunk, at
+	other times one wants the address of the virtual chunk at the
+	end of memory.  The present version returns the address of the
+	(virtual) chunk and relies on the user to test last_mallink(ml)
+	first.
+*/
+#define size_of(ml)		(_this_size_of(ml) - mallink_size())
+#define	set_phys_next(ml,e) \
+	(_this_size_of(ml) = (unsigned int)((char *)(e) - (char *)(ml)))
+#define	phys_next_of(ml)	(mallink *) ((char *)(ml) + _this_size_of(ml))
+
+#define	set_free(ml,e) \
+	(_phys_prev_of(ml) = (mallink *) \
+		((e) ? (size_type) _phys_prev_of(ml) | FREE_BIT : \
+		       (size_type) _phys_prev_of(ml) & ~FREE_BIT))
+#define	free_of(ml)		(__free_of(ml))
+
+#define coalesce_forw(ml,nxt)	( unlink_free_chunk(nxt), \
+				  combine_chunks((ml), (nxt)))
+
+#define coalesce_backw(ml,prv)	( unlink_free_chunk(prv), \
+				  stopped_working_on(ml), \
+				  combine_chunks((prv), (ml)), \
+				  started_working_on(prv))
+
+#ifdef	CHECK
+#define	set_print(ml,e)		(_print_of(ml) = (e))
+#define	print_of(ml)		(_print_of(ml))
+#endif	/* CHECK */
+
+public truncate(mallink *ml, size_t size);
+public combine_chunks(register mallink *ml1, register mallink *ml2);
+public mallink *create_chunk(void *p, size_t n);