remove espie's double-linked-list based allocator and write a

similarily simple one from scratch, which however performs
better than espie's with AFREE_DEBUG enabled which took away
the benefit of the double-linked-list approach

all of (core) mksh is now MirOS licenced

Build.sh

@@ -1,9 +1,9 @@
 #!/bin/sh
-srcversion='$MirOS: src/bin/mksh/Build.sh,v 1.375 2008/12/31 16:09:51 tg Exp $'
+srcversion='$MirOS: src/bin/mksh/Build.sh,v 1.376 2009/03/22 16:55:37 tg Exp $'
 #-
 # Environment used: CC CFLAGS CPPFLAGS LDFLAGS LIBS NOWARN NROFF TARGET_OS
 # CPPFLAGS recognised:	MKSH_SMALL MKSH_ASSUME_UTF8 MKSH_NOPWNAM MKSH_NOVI
-#			MKSH_CLS_STRING MKSH_AFREE_DEBUG MKSH_BINSHREDUCED
+#			MKSH_CLS_STRING MKSH_BINSHREDUCED
 
 LC_ALL=C
 export LC_ALL

Makefile

@@ -1,16 +1,13 @@
-# $MirOS: src/bin/mksh/Makefile,v 1.71 2008/12/13 17:02:10 tg Exp $
+# $MirOS: src/bin/mksh/Makefile,v 1.72 2009/03/22 16:55:37 tg Exp $
 #-
 # use CPPFLAGS=-DDEBUG __CRAZY=Yes to check for certain more stuff
 
 .include <bsd.own.mk>
 
 PROG=		mksh
-SRCS=		alloc.c edit.c eval.c exec.c expr.c funcs.c histrap.c \
+SRCS=		edit.c eval.c exec.c expr.c funcs.c histrap.c jobs.c \
-		jobs.c lex.c main.c misc.c shf.c syn.c tree.c var.c
+		lalloc.c lex.c main.c misc.c shf.c syn.c tree.c var.c
 .if !make(test-build)
-.  if ${DEBUGLIBS:L} == "yes"
-CPPFLAGS+=	-DMKSH_AFREE_DEBUG	# MirOS development version
-.  endif
 CPPFLAGS+=	-DMKSH_ASSUME_UTF8 \
 		-DHAVE_ATTRIBUTE=1 -DHAVE_ATTRIBUTE_BOUNDED=1 \
 		-DHAVE_ATTRIBUTE_USED=1 -DHAVE_SYS_PARAM_H=1 \

alloc.c

@@ -1,132 +0,0 @@
-/*	$OpenBSD: alloc.c,v 1.8 2008/07/21 17:30:08 millert Exp $	*/
-
-/*-
- * Copyright (c) 2002 Marc Espie.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS
- * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OPENBSD
- * PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *-
- * area-based allocation built on malloc/free
- */
-
-#include "sh.h"
-
-__RCSID("$MirOS: src/bin/mksh/alloc.c,v 1.13 2008/12/13 17:02:11 tg Exp $");
-
-struct link {
-	struct link *prev;
-	struct link *next;
-};
-
-Area *
-ainit(Area *ap)
-{
-	ap->freelist = NULL;
-	return (ap);
-}
-
-void
-afreeall(Area *ap)
-{
-	struct link *l, *l2;
-
-	for (l = ap->freelist; l != NULL; l = l2) {
-		l2 = l->next;
-		free(l);
-	}
-	ap->freelist = NULL;
-}
-
-#define L2P(l)	( (void *)(((char *)(l)) + sizeof (struct link)) )
-#define P2L(p)	( (struct link *)(((ptrdiff_t)(p)) - sizeof (struct link)) )
-
-void *
-alloc(size_t size, Area *ap)
-{
-	struct link *l;
-
-	if ((l = malloc(sizeof (struct link) + size)) == NULL)
-		internal_errorf("unable to allocate memory");
-	l->next = ap->freelist;
-	l->prev = NULL;
-	if (ap->freelist)
-		ap->freelist->prev = l;
-	ap->freelist = l;
-
-	return (L2P(l));
-}
-
-void *
-aresize(void *ptr, size_t size, Area *ap)
-{
-	struct link *l, *l2, *lprev, *lnext;
-
-	if (ptr == NULL)
-		return (alloc(size, ap));
-
-	l = P2L(ptr);
-	lprev = l->prev;
-	lnext = l->next;
-
-	if ((l2 = realloc(l, sizeof (struct link) + size)) == NULL)
-		internal_errorf("unable to allocate memory");
-	if (lprev)
-		lprev->next = l2;
-	else
-		ap->freelist = l2;
-	if (lnext)
-		lnext->prev = l2;
-
-	return (L2P(l2));
-}
-
-void
-afree(void *ptr, Area *ap)
-{
-	struct link *l;
-#ifdef MKSH_AFREE_DEBUG
-	struct link *lp;
-#endif
-
-	if (!ptr)
-		return;
-
-	l = P2L(ptr);
-
-#ifdef MKSH_AFREE_DEBUG
-	for (lp = ap->freelist; lp != NULL; lp = lp->next)
-		if (l == lp)
-			break;
-	if (lp == NULL) {
-		internal_warningf("afree: pointer %p not allocated", ptr);
-		exit(255);
-	}
-#endif
-
-	if (l->prev)
-		l->prev->next = l->next;
-	else
-		ap->freelist = l->next;
-	if (l->next)
-		l->next->prev = l->prev;
-
-	free(l);
-}

copyright

@@ -1,4 +1,4 @@
-$MirOS: src/bin/mksh/copyright,v 1.27 2009/02/20 13:21:06 tg Exp $
+$MirOS: src/bin/mksh/copyright,v 1.28 2009/03/22 16:55:38 tg Rel $
 
 The MirBSD Korn Shell (mksh) is
 
@@ -25,8 +25,6 @@ The developer of mksh recognises the efforts of the pdksh authors,
 who had dedicated their work into Public Domain, and all contribu-
 tors. See the documentation, CVS, and web site for details.
 
-A number of files that are either always or conditionally included
+Depending on the target operating environment, setmode.c (3-clause
-during compilation, depending on the target operating environment,
+BSD licence) or strlcpy.c (ISC licence) may be added during compi-
-are covered by different (2/3-clause BSD or similar) licences; re-
+lation; refer to these files for details.
-fer to the individual files for details: alloc.c (always included)
-and setmode.c, strlcpy.c (included when required)

lalloc.c

@@ -0,0 +1,86 @@
+#include "sh.h"
+
+__RCSID("$MirOS: src/bin/mksh/lalloc.c,v 1.1 2009/03/22 16:55:38 tg Exp $");
+
+struct lalloc {
+	struct lalloc *next;	/* entry pointer, must be first */
+	Area *group;		/* group backpointer */
+};
+
+static void findptr(struct lalloc **, struct lalloc **, char *, Area *);
+
+void
+ainit(Area *ap)
+{
+	ap->ent = NULL;
+}
+
+static void
+findptr(struct lalloc **lpp, struct lalloc **ppp, char *ptr, Area *ap)
+{
+	*lpp = (struct lalloc *)(ptr - sizeof (struct lalloc));
+	if ((*lpp)->group != ap)
+ notfound:
+		internal_errorf("pointer %p not in group %p", ptr, ap);
+	*ppp = (struct lalloc *)ap;
+	while ((*ppp)->next != *lpp)
+		if (((*ppp) = (*ppp)->next) == NULL)
+			goto notfound;
+}
+
+void *
+aresize(void *ptr, size_t numb, Area *ap)
+{
+	struct lalloc *lp, *pp;
+
+	if (numb >= SIZE_MAX - sizeof (struct lalloc))
+ failure:
+		internal_errorf("cannot allocate %lu data bytes",
+		    (unsigned long)numb);
+
+	if (ptr == NULL) {
+		pp = (struct lalloc *)ap;
+		lp = malloc(numb + sizeof (struct lalloc));
+	} else {
+		findptr(&lp, &pp, ptr, ap);
+		lp = realloc(lp, numb + sizeof (struct lalloc));
+	}
+	if (lp == NULL)
+		goto failure;
+	if (ptr == NULL) {
+		lp->group = ap;
+		lp->next = ap->ent;
+	}
+	pp->next = lp;
+	return ((char *)lp + sizeof (struct lalloc));
+}
+
+void
+afree(void *ptr, Area *ap)
+{
+	struct lalloc *lp, *pp;
+
+	if (ptr == NULL)
+		return;
+
+	findptr(&lp, &pp, ptr, ap);
+	pp->next = lp->next;
+	/* lp->group = NULL; */
+	free(lp);
+}
+
+void
+afreeall(Area *ap)
+{
+	struct lalloc *lp;
+
+	while ((lp = ap->ent) != NULL) {
+#ifndef MKSH_SMALL
+		if (lp->group != ap)
+			internal_errorf("rogue pointer in group %p", ap);
+#endif
+		ap->ent = lp->next;
+		/* lp->group = NULL; */
+		free(lp);
+	}
+}

sh.h

@@ -102,7 +102,7 @@
 #define __SCCSID(x)	__IDSTRING(sccsid,x)
 
 #ifdef EXTERN
-__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.279 2009/03/17 13:56:45 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.280 2009/03/22 16:55:38 tg Exp $");
 #endif
 #define MKSH_VERSION "R36 2009/03/17"
 
@@ -396,10 +396,10 @@ char *ucstrstr(char *, const char *);
 #endif
 
 /*
- * Area-based allocation built on malloc/free
+ * simple grouping allocator
  */
-typedef struct Area {
+typedef struct {
-	struct link *freelist;	/* free list */
+	void *ent;		/* entry pointer, must be first */
 } Area;
 
 EXTERN Area aperm;		/* permanent object space */
@@ -1263,10 +1263,11 @@ EXTERN int histsize;	/* history size */
 /* user and system time of last j_waitjed job */
 EXTERN struct timeval j_usrtime, j_systime;
 
-/* alloc.c */
+/* lalloc.c */
-Area *ainit(Area *);
+void ainit(Area *);
 void afreeall(Area *);
-void *alloc(size_t, Area *);	/* cannot fail */
+/* these cannot fail and can take NULL (not for ap) */
+#define alloc(n, ap)	aresize(NULL, (n), (ap))
 void *aresize(void *, size_t, Area *);
 void afree(void *, Area *);	/* can take NULL */
 /* edit.c */