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-rw-r--r--db2/common/db_salloc.c302
1 files changed, 0 insertions, 302 deletions
diff --git a/db2/common/db_salloc.c b/db2/common/db_salloc.c
deleted file mode 100644
index d58b79f3c4..0000000000
--- a/db2/common/db_salloc.c
+++ /dev/null
@@ -1,302 +0,0 @@
-/*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1996, 1997, 1998
- *	Sleepycat Software.  All rights reserved.
- */
-
-#include "config.h"
-
-#ifndef lint
-static const char sccsid[] = "@(#)db_salloc.c	10.14 (Sleepycat) 11/16/98";
-#endif /* not lint */
-
-#ifndef NO_SYSTEM_INCLUDES
-#include <sys/types.h>
-
-#include <errno.h>
-#include <string.h>
-#endif
-
-#include "db_int.h"
-#include "shqueue.h"
-#include "common_ext.h"
-
-/*
- * Implement shared memory region allocation, using simple first-fit algorithm.
- * The model is that we take a "chunk" of shared memory store and begin carving
- * it up into areas, similarly to how malloc works.  We do coalescing on free.
- *
- * The "len" field in the __data struct contains the length of the free region
- * (less the size_t bytes that holds the length).  We use the address provided
- * by the caller to find this length, which allows us to free a chunk without
- * requiring that the caller pass in the length of the chunk they're freeing.
- */
-SH_LIST_HEAD(__head);
-struct __data {
-	size_t len;
-	SH_LIST_ENTRY links;
-};
-
-/*
- * __db_shalloc_init --
- *	Initialize the area as one large chunk.
- *
- * PUBLIC: void __db_shalloc_init __P((void *, size_t));
- */
-void
-__db_shalloc_init(area, size)
-	void *area;
-	size_t size;
-{
-	struct __data *elp;
-	struct __head *hp;
-
-	hp = area;
-	SH_LIST_INIT(hp);
-
-	elp = (struct __data *)(hp + 1);
-	elp->len = size - sizeof(struct __head) - sizeof(elp->len);
-	SH_LIST_INSERT_HEAD(hp, elp, links, __data);
-}
-
-/*
- * __db_shalloc --
- *	Allocate some space from the shared region.
- *
- * PUBLIC: int __db_shalloc __P((void *, size_t, size_t, void *));
- */
-int
-__db_shalloc(p, len, align, retp)
-	void *p, *retp;
-	size_t len, align;
-{
-	struct __data *elp;
-	size_t *sp;
-	void *rp;
-
-	/*
-	 * We never allocate less than the size of a struct __data, align
-	 * to less than a size_t boundary, or align to something that's not
-	 * a multiple of a size_t.
-	 */
-	if (len < sizeof(struct __data))
-		len = sizeof(struct __data);
-	align = align <= sizeof(size_t) ?
-	    sizeof(size_t) : ALIGN(align, sizeof(size_t));
-
-	/* Walk the list, looking for a slot. */
-	for (elp = SH_LIST_FIRST((struct __head *)p, __data);
-	    elp != NULL;
-	    elp = SH_LIST_NEXT(elp, links, __data)) {
-		/*
-		 * Calculate the value of the returned pointer if we were to
-		 * use this chunk.
-		 *	+ Find the end of the chunk.
-		 *	+ Subtract the memory the user wants.
-		 *	+ Find the closest previous correctly-aligned address.
-		 */
-		rp = (u_int8_t *)elp + sizeof(size_t) + elp->len;
-		rp = (u_int8_t *)rp - len;
-		rp = (u_int8_t *)((ALIGNTYPE)rp & ~(align - 1));
-
-		/*
-		 * Rp may now point before elp->links, in which case the chunk
-		 * was too small, and we have to try again.
-		 */
-		if ((u_int8_t *)rp < (u_int8_t *)&elp->links)
-			continue;
-
-		*(void **)retp = rp;
-
-#define	SHALLOC_FRAGMENT	32
-		/*
-		 * If there are at least SHALLOC_FRAGMENT additional bytes of
-		 * memory, divide the chunk into two chunks.
-		 */
-		if ((u_int8_t *)rp >=
-		    (u_int8_t *)&elp->links + SHALLOC_FRAGMENT) {
-			sp = rp;
-			*--sp = elp->len -
-			    ((u_int8_t *)rp - (u_int8_t *)&elp->links);
-			elp->len -= *sp + sizeof(size_t);
-			return (0);
-		}
-
-		/*
-		 * Otherwise, we return the entire chunk, wasting some amount
-		 * of space to keep the list compact.  However, because the
-		 * address we're returning to the user may not be the address
-		 * of the start of the region for alignment reasons, set the
-		 * size_t length fields back to the "real" length field to a
-		 * flag value, so that we can find the real length during free.
-		 */
-#define	ILLEGAL_SIZE	1
-		SH_LIST_REMOVE(elp, links, __data);
-		for (sp = rp; (u_int8_t *)--sp >= (u_int8_t *)&elp->links;)
-			*sp = ILLEGAL_SIZE;
-		return (0);
-	}
-
-	/* Nothing found large enough; need to grow the region. */
-	return (ENOMEM);
-}
-
-/*
- * __db_shalloc_free --
- *	Free a shared memory allocation.
- *
- * PUBLIC: void __db_shalloc_free __P((void *, void *));
- */
-void
-__db_shalloc_free(regionp, ptr)
-	void *regionp, *ptr;
-{
-	struct __data *elp, *lastp, *newp;
-	struct __head *hp;
-	size_t free_size, *sp;
-	int merged;
-
-	/*
-	 * Step back over flagged length fields to find the beginning of
-	 * the object and its real size.
-	 */
-	for (sp = (size_t *)ptr; sp[-1] == ILLEGAL_SIZE; --sp)
-		;
-	ptr = sp;
-
-	newp = (struct __data *)((u_int8_t *)ptr - sizeof(size_t));
-	free_size = newp->len;
-
-	/* Trash the returned memory. */
-#ifdef DIAGNOSTIC
-	memset(ptr, 0xdb, free_size);
-#endif
-
-	/*
-	 * Walk the list, looking for where this entry goes.
-	 *
-	 * We keep the free list sorted by address so that coalescing is
-	 * trivial.
-	 *
-	 * XXX
-	 * Probably worth profiling this to see how expensive it is.
-	 */
-	hp = (struct __head *)regionp;
-	for (elp = SH_LIST_FIRST(hp, __data), lastp = NULL;
-	    elp != NULL && (void *)elp < (void *)ptr;
-	    lastp = elp, elp = SH_LIST_NEXT(elp, links, __data))
-		;
-
-	/*
-	 * Elp is either NULL (we reached the end of the list), or the slot
-	 * after the one that's being returned.  Lastp is either NULL (we're
-	 * returning the first element of the list) or the element before the
-	 * one being returned.
-	 *
-	 * Check for coalescing with the next element.
-	 */
-	merged = 0;
-	if ((u_int8_t *)ptr + free_size == (u_int8_t *)elp) {
-		newp->len += elp->len + sizeof(size_t);
-		SH_LIST_REMOVE(elp, links, __data);
-		if (lastp != NULL)
-			SH_LIST_INSERT_AFTER(lastp, newp, links, __data);
-		else
-			SH_LIST_INSERT_HEAD(hp, newp, links, __data);
-		merged = 1;
-	}
-
-	/* Check for coalescing with the previous element. */
-	if (lastp != NULL && (u_int8_t *)lastp +
-	    lastp->len + sizeof(size_t) == (u_int8_t *)newp) {
-		lastp->len += newp->len + sizeof(size_t);
-
-		/*
-		 * If we have already put the new element into the list take
-		 * it back off again because it's just been merged with the
-		 * previous element.
-		 */
-		if (merged)
-			SH_LIST_REMOVE(newp, links, __data);
-		merged = 1;
-	}
-
-	if (!merged) {
-		if (lastp == NULL)
-			SH_LIST_INSERT_HEAD(hp, newp, links, __data);
-		else
-			SH_LIST_INSERT_AFTER(lastp, newp, links, __data);
-	}
-}
-
-/*
- * __db_shalloc_count --
- *	Return the amount of memory on the free list.
- *
- * PUBLIC: size_t __db_shalloc_count __P((void *));
- */
-size_t
-__db_shalloc_count(addr)
-	void *addr;
-{
-	struct __data *elp;
-	size_t count;
-
-	count = 0;
-	for (elp = SH_LIST_FIRST((struct __head *)addr, __data);
-	    elp != NULL;
-	    elp = SH_LIST_NEXT(elp, links, __data))
-		count += elp->len;
-
-	return (count);
-}
-
-/*
- * __db_shsizeof --
- *	Return the size of a shalloc'd piece of memory.
- *
- * PUBLIC: size_t __db_shsizeof __P((void *));
- */
-size_t
-__db_shsizeof(ptr)
-	void *ptr;
-{
-	struct __data *elp;
-	size_t *sp;
-
-	/*
-	 * Step back over flagged length fields to find the beginning of
-	 * the object and its real size.
-	 */
-	for (sp = (size_t *)ptr; sp[-1] == ILLEGAL_SIZE; --sp)
-		;
-
-	elp = (struct __data *)((u_int8_t *)sp - sizeof(size_t));
-	return (elp->len);
-}
-
-/*
- * __db_shalloc_dump --
- *
- * PUBLIC: void __db_shalloc_dump __P((void *, FILE *));
- */
-void
-__db_shalloc_dump(addr, fp)
-	void *addr;
-	FILE *fp;
-{
-	struct __data *elp;
-
-	/* Make it easy to call from the debugger. */
-	if (fp == NULL)
-		fp = stderr;
-
-	fprintf(fp, "%s\nMemory free list\n", DB_LINE);
-
-	for (elp = SH_LIST_FIRST((struct __head *)addr, __data);
-	    elp != NULL;
-	    elp = SH_LIST_NEXT(elp, links, __data))
-		fprintf(fp, "%#lx: %lu\t", (u_long)elp, (u_long)elp->len);
-	fprintf(fp, "\n");
-}