Fix a bug with ArrayList_Deinit_f (tried too hard to be clever), and add

an incremental, reference counting garbage collector for QFobjects.  A
different kind of collector will eventually be needed to run once in a
while to sweep up cyclic structures.

include/Makefile.am

@@ -4,7 +4,7 @@ SUBDIRS = QF
 EXTRA_DIST = asm_i386.h alsa_funcs_list.h adivtab.h anorm_dots.h anorms.h \
 	asm_draw.h block16.h block8.h buildnum.h compat.h context_sdl.h \
 	context_x11.h d_iface.h d_ifacea.h d_local.h dga_check.h exp.h fbset.h \
-	getopt.h gib_buffer.h gib_builtin.h gib_classes.h gib_execute.h gib_function.h \
+	garbage.h getopt.h gib_buffer.h gib_builtin.h gib_classes.h gib_execute.h gib_function.h \
 	gib_handle.h gib_object.h gib_parse.h gib_process.h gib_regex.h gib_semantics.h \
 	gib_thread.h gib_tree.h gib_vars.h gl_warp_sin.h in_win.h logos.h menu.h \
 	net_dgrm.h net_loop.h net_udp.h net_vcr.h net_wins.h netchan.h netmain.h \

include/QF/object.h

@@ -40,14 +40,14 @@
 
 #ifdef __GNUC__
 #define superInit(cl, obj, args...) (cl##_class->parent->init ((obj) , ## args))
-#define new(cl, args...) ((void *) (cl##_class->abstract ? NULL : retain(cl##_class->init (Object_Create(cl##_class) , ## args))))
-#define newFloat(cl, args...) ((void *) (cl##_class->abstract ? NULL : cl##_class->init (Object_Create(cl##_class) , ## args)))
+#define new(cl, args...) ((void *) (cl##_class->abstract ? NULL : cl##_class->init (Object_Create(cl##_class, false), ## args)))
+#define newFloat(cl, args...) ((void *) (cl##_class->abstract ? NULL : cl##_class->init (Object_Create(cl##_class, true) , ## args)))
 #define methodCall(obj, m, args...) ((obj)->m(obj , ## args))
 #define methodDecl(type, name, args...) (* name) (struct type##_s *self , ## args)
 #else
 #define superInit(cl, obj, ...) (cl##_class->parent->init ((obj), ##__VA_ARGS__))
-#define new(cl, ...) ((void *) (cl##_class->abstract ? NULL : retain(cl##_class->init (Object_Create(cl##_class), ##__VA_ARGS__))))
-#define newFloat(cl, ...) ((void *) (cl##_class->abstract ? NULL : cl##_class->init (Object_Create(cl##_class), ##__VA_ARGS__)))
+#define new(cl, ...) ((void *) (cl##_class->abstract ? NULL : cl##_class->init (Object_Create(cl##_class, false) , ##__VA_ARGS__)))
+#define newFloat(cl, ...) ((void *) (cl##_class->abstract ? NULL : cl##_class->init (Object_Create(cl##_class, true) , ##__VA_ARGS__)))
 #define methodCall(obj, m, ...) ((obj)->m(obj, ##__VA_ARGS__))
 #define methodDecl(type, name, ...) (* name) (struct type##_s *self, ##__VA_ARGS__)
 #endif
@@ -70,9 +70,12 @@ typedef void (*ReplyHandler_t) (struct Object_s *retValue);
 typedef struct Object_s {
 	struct Class_s *cl;
 	int refs;
+	qboolean junked;
+	struct Object_s *next;
 	struct String_s * methodDecl(Object, toString);
 	void methodDecl(Object, message, const char *name, struct List_s *args, struct Object_s *sender, ReplyHandler_t *reply);
 	void *data;
+
 } Object;
 extern struct Class_s * Object_class;
 #define OBJECT(o) ((Object *)(o))
@@ -91,12 +94,13 @@ classDecl (Class, Object,
 );
 #define CLASS(o) ((Class *)(o))
 
-Object *Object_Create (Class *cl);
+Object *Object_Create (Class *cl, qboolean floating);
 void Object_Delete (Object *obj);
 Object *Object_Retain (Object *obj);
 Object *Object_Release (Object *obj);
 qboolean Object_InstanceOf (Object *obj, Class *cl);
 void Object_Init (void);
+void Object_Garbage_Collect (void);
 
 #include "QF/classes/List.h"
 #include "QF/classes/String.h"

include/garbage.h

@@ -0,0 +1,39 @@
+/*
+	garbage.h
+
+	Object system garbage collector
+
+	Copyright (C) 2003 Brian Koropoff
+
+	Author: Brian Koropoff
+	Date: November 28, 2003
+
+	This program is free software; you can redistribute it and/or
+	modify it under the terms of the GNU General Public License
+	as published by the Free Software Foundation; either version 2
+	of the License, or (at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+	See the GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to:
+
+		Free Software Foundation, Inc.
+		59 Temple Place - Suite 330
+		Boston, MA  02111-1307, USA
+
+	$Id$
+*/
+
+#ifndef __garbage_h
+#define __garbage_h
+
+void Garbage_Junk_Object (Object *o);
+unsigned int Garbage_Amount (void);
+void Garbage_Collect (unsigned int amount);
+
+#endif

libs/object/ArrayList.c

@@ -214,7 +214,7 @@ static void
 ArrayList_Deinit_f (Object *self)
 {
 	unsigned int i;
-	for (i = COLLECTION(self)->count; --i > 0;)
+	for (i = 0; i < COLLECTION(self)->count; i++)
 		if (ARRAYLIST(self)->elements[i])
 			release(ARRAYLIST(self)->elements[i]);
 	free(ARRAYLIST(self)->elements);

libs/object/Makefile.am

@@ -7,4 +7,4 @@ lib_LTLIBRARIES= libQFobject.la
 libQFobject_la_LDFLAGS=		-version-info 1:0:0
 libQFobject_la_SOURCES= \
 	ArrayList.c Collection.c Double.c Integer.c Iterator.c \
-	List.c Number.c String.c object.c
+	List.c Number.c String.c garbage.c object.c

libs/object/garbage.c

@@ -0,0 +1,89 @@
+/*
+	garbage.c
+
+	Object system garbage collector.
+
+	Copyright (C) 2003 Brian Koropoff
+
+	Author: Brian Koropoff
+	Date: November 28, 2003
+
+	This program is free software; you can redistribute it and/or
+	modify it under the terms of the GNU General Public License
+	as published by the Free Software Foundation; either version 2
+	of the License, or (at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+	See the GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to:
+
+		Free Software Foundation, Inc.
+		59 Temple Place - Suite 330
+		Boston, MA  02111-1307, USA
+
+*/
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+static __attribute__ ((unused)) const char rcsid[] =
+	"$Id$";
+
+#include <stdlib.h>
+
+#include "QF/sys.h"
+#include "QF/object.h"
+
+#include "garbage.h"
+
+unsigned int junked = 0;
+Object *junk = NULL;
+
+void
+Garbage_Junk_Object (Object *o)
+{
+	Sys_DPrintf ("GC: %s@%p ready for collection.\n", o->cl->name, o);
+	if (!o->junked && !o->refs) {
+		o->next = junk;
+		junk = o;
+		o->junked = true;
+		junked++;
+	}
+}
+
+unsigned int
+Garbage_Amount (void)
+{
+	return junked;
+}
+
+
+void
+Garbage_Collect (unsigned int amount)
+{
+	Object *o;
+
+	if (!amount)
+		return;
+	Sys_DPrintf ("GC: Collecting %u objects...\n", amount);
+
+	for (o = junk; o && amount; o = junk) {
+		junk = o->next;
+		if (!o->refs) {
+			Sys_DPrintf("GC: Collecting %s@%p...\n", o->cl->name, o);
+			Object_Delete (o);
+			amount--;
+		} else {
+			Sys_DPrintf("GC: %s@%p gained references, not collecting...\n", o->cl->name, o);
+			o->junked = false;
+		}
+		junked--;
+	}
+	junk = o;
+}

libs/object/object.c

@@ -52,7 +52,7 @@ static __attribute__ ((unused)) const char rcsid[] =
 #include "QF/sys.h"
 #include "QF/object.h"
 #include "QF/va.h"
-#include "QF/object.h"
+#include "garbage.h"
 
 #include "QF/classes/ArrayList.h"
 #include "QF/classes/Integer.h"
@@ -67,7 +67,6 @@ Object_ToString_f (Object *self)
 static void
 Object_Init_f (Object *self) 
 {
-	self->refs = -1; // Floating reference
 	self->toString = Object_ToString_f;
 	Sys_DPrintf("%s@%p initing...\n", self->cl->name, self);
 }
@@ -105,10 +104,16 @@ Class_Deinit_f (Object *self) {
 
 
 Object *
-Object_Create (Class *cl)
+Object_Create (Class *cl, qboolean floating)
 {
 	Object *new = malloc (cl->size);
 	new->cl = cl;
+	new->junked = false;
+	if (floating) {
+		new->refs = 0;
+		Garbage_Junk_Object (new);
+	} else
+		new->refs = 1;
 	return new;
 }
 
@@ -123,23 +128,15 @@ Object_Delete (Object *obj)
 Object *
 Object_Retain (Object *obj)
 {
-	if (obj->refs == -1) {
-		obj->refs = 1;
-	} else {
-		obj->refs++;
-	}
+	obj->refs++;
 	return obj;
 }
 
 Object *
 Object_Release (Object *obj)
 {
-	if (obj->refs == -1)
-		Sys_Error ("%s@%p with floating reference released.", obj->cl->name, obj);
-	if (--obj->refs < 1) {
-		Object_Delete (obj);
-		return NULL;
-	}
+	if (obj->refs && --obj->refs == 0)
+		Garbage_Junk_Object (obj);
 	return obj;
 }
 
@@ -214,3 +211,11 @@ Object_Init (void)
 	/* Run test */
 	Object_Test();
 }
+
+void
+Object_Garbage_Collect (void)
+{
+	unsigned int amount;
+	if ((amount = Garbage_Amount()))
+		Garbage_Collect (amount / 2 + 1);
+}

qw/source/sv_main.c

@@ -1895,6 +1895,8 @@ SV_CheckVars (void)
 	SV_GarbageCollect
 
 	Run string GC on progs every pr_gc_interval frames
+	
+	snax: run QFobject GC as well
 */
 static void
 SV_GarbageCollect (void)
@@ -1905,6 +1907,7 @@ SV_GarbageCollect (void)
 		if (pr_gc_count >= pr_gc_interval->int_val) {
 			pr_gc_count = 0;
 			PR_GarbageCollect (&sv_pr_state);
+			Object_Garbage_Collect ();
 		}
 	} else {
 		// Make sure the count gets reset if the gc is disabled.  I