From 9e3cfe2bb82e7af14e4bfa9959eb01e84716d081 Mon Sep 17 00:00:00 2001
From: temx <nukhead@gmail.com>
Date: Sun, 16 Apr 2023 23:34:51 +0200
Subject: [PATCH] Restore part of "Trim edict list on load" in order to fix
 'autofastload' Otherwise autofastload leaks edicts, eventually aborting game
 when max_edicts is reached BEWARE: this _may_ break old savegames !

---
 Quake/host_cmd.c | 38 +++++++++++-----------------
 Quake/pr_edict.c | 64 ++++++++++++++++++++++++++++++++----------------
 Quake/progs.h    |  1 +
 3 files changed, 58 insertions(+), 45 deletions(-)

diff --git a/Quake/host_cmd.c b/Quake/host_cmd.c
index 2caf61a1..ad40d7cf 100644
--- a/Quake/host_cmd.c
+++ b/Quake/host_cmd.c
@@ -1306,7 +1306,7 @@ static void Host_Loadgame_f (void)
 	const char *data;
 	int			i;
 	edict_t	   *ent;
-	int			entnum;
+	int			entnum, lastusedent;
 	int			version;
 	float		spawn_parms[NUM_TOTAL_SPAWN_PARMS];
 	qboolean	was_recording = cls.demorecording;
@@ -1446,7 +1446,8 @@ static void Host_Loadgame_f (void)
 		PR_ClearEdictStrings ();
 
 	// load the edicts out of the savegame file
-	entnum = -1; // -1 is the globals
+	qcvm->time = 0;			   // mark freed edicts for immediate reuse
+	entnum = lastusedent = -1; // -1 is the globals
 	while (*data)
 	{
 		while (*data == ' ' || *data == '\r' || *data == '\n')
@@ -1571,22 +1572,7 @@ static void Host_Loadgame_f (void)
 			if (entnum < qcvm->num_edicts)
 			{
 				if (ent->free)
-				{
-					if (qcvm->free_edicts_head == ent)
-					{
-						assert (!ent->prev_free);
-						qcvm->free_edicts_head = ent->next_free;
-					}
-					if (qcvm->free_edicts_tail == ent)
-					{
-						assert (!ent->next_free);
-						qcvm->free_edicts_tail = ent->prev_free;
-					}
-					if (ent->prev_free)
-						ent->prev_free->next_free = ent->next_free;
-					if (ent->next_free)
-						ent->next_free->prev_free = ent->prev_free;
-				}
+					ED_RemoveFromFreeList (ent);
 				ent->free = false;
 				ent->next_free = NULL;
 				ent->prev_free = NULL;
@@ -1601,15 +1587,23 @@ static void Host_Loadgame_f (void)
 
 			// link it into the bsp tree
 			if (!ent->free)
+			{
 				SV_LinkEdict (ent, false);
+				lastusedent = entnum;
+			}
 		}
 
 		entnum++;
 	}
 
-	qcvm->time = time;
-	for (i = entnum; i < qcvm->num_edicts; i++)
+	for (i = lastusedent + 1; i < q_max (qcvm->num_edicts, entnum); i++)
+	{
 		ED_Free (EDICT_NUM (i));
+		ED_RemoveFromFreeList (EDICT_NUM (i));
+		memset (EDICT_NUM (i), 0, qcvm->edict_size);
+	}
+	qcvm->time = time;
+	qcvm->num_edicts = lastusedent + 1;
 
 	if (fastload)
 	{
@@ -1627,10 +1621,6 @@ static void Host_Loadgame_f (void)
 
 		Send_Spawn_Info (svs.clients, true);
 	}
-	else if (entnum < qcvm->num_edicts)
-		Con_Warning ("Save game had less entities than map (%d < %d)\n", entnum, qcvm->num_edicts); // should be Host_Error, but try to recover
-
-	qcvm->num_edicts = q_max (qcvm->num_edicts, entnum);
 
 	Mem_Free (start);
 	start = NULL;
diff --git a/Quake/pr_edict.c b/Quake/pr_edict.c
index 42e7da5d..57cf3be3 100644
--- a/Quake/pr_edict.c
+++ b/Quake/pr_edict.c
@@ -142,6 +142,33 @@ void ED_Free (edict_t *ed)
 	}
 }
 
+/*
+=================
+ED_RemoveFromFreeList
+
+Used at load time to place edicts at a specifit spot, and to trim qcvm->num_edicts
+=================
+*/
+void ED_RemoveFromFreeList (edict_t *ed)
+{
+	assert (ed->free);
+
+	if (qcvm->free_edicts_head == ed)
+	{
+		assert (!ed->prev_free);
+		qcvm->free_edicts_head = ed->next_free;
+	}
+	if (qcvm->free_edicts_tail == ed)
+	{
+		assert (!ed->next_free);
+		qcvm->free_edicts_tail = ed->prev_free;
+	}
+	if (ed->prev_free)
+		ed->prev_free->next_free = ed->next_free;
+	if (ed->next_free)
+		ed->next_free->prev_free = ed->prev_free;
+}
+
 //===========================================================================
 
 /*
@@ -738,42 +765,37 @@ For savegames
 */
 void ED_Write (FILE *f, edict_t *ed)
 {
-	ddef_t	   *d;
-	int		   *v;
-	int			i, j;
-	const char *name;
-	int			type;
-
-	fprintf (f, "{\n");
+	ddef_t *d;
+	int	   *v;
+	int		i;
+	int		type;
 
 	if (ed->free)
 	{
-		fprintf (f, "}\n");
+		fprintf (f, "{\n}\n");
 		return;
 	}
 
+	fprintf (f, "{\n");
+
 	for (i = 1; i < qcvm->progs->numfielddefs; i++)
 	{
 		d = &qcvm->fielddefs[i];
-		name = PR_GetString (d->s_name);
-		j = strlen (name);
-		if (j > 1 && name[j - 2] == '_')
-			continue; // skip _x, _y, _z vars
+		type = d->type;
+		assert (!!(type & DEF_SAVEGLOBAL) == (strlen (PR_GetString (d->s_name)) > 1 && PR_GetString (d->s_name)[strlen (PR_GetString (d->s_name)) - 2] == '_'));
+		if (type & DEF_SAVEGLOBAL)
+			continue;
 
 		v = (int *)((char *)&ed->v + d->ofs * 4);
 
 		// if the value is still all 0, skip the field
-		type = d->type & ~DEF_SAVEGLOBAL;
-		for (j = 0; j < type_size[type]; j++)
-		{
-			if (v[j])
-				break;
-		}
-		if (j == type_size[type])
+		assert (type < 8 && ((type == ev_vector && type_size[type] == 3) || (type != ev_vector && type_size[type] == 1)));
+		if (type != ev_vector && !v[0])
+			continue;
+		if (type == ev_vector && !v[0] && !v[1] && !v[2])
 			continue;
 
-		fprintf (f, "\"%s\" ", name);
-		fprintf (f, "\"%s\"\n", PR_UglyValueString (d->type, (eval_t *)v));
+		fprintf (f, "\"%s\" \"%s\"\n", PR_GetString (d->s_name), PR_UglyValueString (d->type, (eval_t *)v));
 	}
 
 	// johnfitz -- save entity alpha manually when progs.dat doesn't know about alpha
diff --git a/Quake/progs.h b/Quake/progs.h
index b5b9173e..e74b28ab 100644
--- a/Quake/progs.h
+++ b/Quake/progs.h
@@ -111,6 +111,7 @@ void PR_Profile_f (void);
 
 edict_t *ED_Alloc (void);
 void	 ED_Free (edict_t *ed);
+void	 ED_RemoveFromFreeList (edict_t *ed);
 
 void		ED_Print (edict_t *ed);
 void		ED_Write (FILE *f, edict_t *ed);