From 0a203c0ab5da922cbc04de8e482dbe52c26e61d4 Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Wed, 13 Jan 2010 06:36:54 +0000
Subject: [PATCH] qccx (etc) "integer" autodetection.

Check for usage of denormal floats and if found, either bail with a
descriptive error message or give a mild warning that things will probably
break. This avoids the possibility of things like RuneQuake getting "lucky"
and doing real harm, and certainly avoids the segfaults.
---
 include/QF/progs.h               |  1 +
 libs/gamecode/engine/pr_load.c   |  2 ++
 libs/gamecode/engine/pr_opcode.c | 24 +++++++++++++++++++++++-
 3 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/include/QF/progs.h b/include/QF/progs.h
index 308c37b05..61506e637 100644
--- a/include/QF/progs.h
+++ b/include/QF/progs.h
@@ -1372,6 +1372,7 @@ struct progs_s {
 	dprograms_t *progs;
 	int         progs_size;
 	unsigned short crc;
+	int         denorm_found;
 
 	struct memzone_s *zone;
 	int         zone_size;
diff --git a/libs/gamecode/engine/pr_load.c b/libs/gamecode/engine/pr_load.c
index 01205dcdf..d7b2d76ae 100644
--- a/libs/gamecode/engine/pr_load.c
+++ b/libs/gamecode/engine/pr_load.c
@@ -127,6 +127,8 @@ PR_LoadProgsFile (progs_t * pr, QFile *file, int size, int edicts, int zone)
 	// store prog crc
 	pr->crc = CRC_Block ((byte*)&progs, sizeof (progs));
 
+	pr->denorm_found = 0;
+
 	// byte swap the header
 	for (i = 0; i < sizeof (progs) / 4; i++)
 		((int *) &progs)[i] = LittleLong (((int *) &progs)[i]);
diff --git a/libs/gamecode/engine/pr_opcode.c b/libs/gamecode/engine/pr_opcode.c
index f57ea7685..f98a3300c 100644
--- a/libs/gamecode/engine/pr_opcode.c
+++ b/libs/gamecode/engine/pr_opcode.c
@@ -45,6 +45,7 @@ static __attribute__ ((used)) const char rcsid[] =
 #include "QF/hash.h"
 #include "QF/pr_comp.h"
 #include "QF/progs.h"
+#include "QF/sys.h"
 
 hashtab_t *opcode_table;
 
@@ -1197,6 +1198,8 @@ check_branch (progs_t *pr, dstatement_t *st, opcode_t *op, short offset)
 				  (long)(st - pr->pr_statements), op->opname);
 }
 
+#define ISDENORM(x) ((x) && !((x) & 0x7f800000))
+
 static inline void
 check_global (progs_t *pr, dstatement_t *st, opcode_t *op, etype_t type,
 			  unsigned short operand)
@@ -1218,6 +1221,22 @@ check_global (progs_t *pr, dstatement_t *st, opcode_t *op, etype_t type,
 				msg = "out of bounds global index";
 				goto error;
 			}
+			if (type == ev_float)
+			if (ISDENORM (G_INT (pr, operand))
+				&& !pr->denorm_found) {
+				pr->denorm_found = 1;
+				if (pr_boundscheck-> int_val) {
+					Sys_Printf ("DENORMAL floats detected, these progs might "
+								"not work. Good luck.\n");
+					return;
+				}
+				msg = "DENORMAL float detected. These progs are probably "
+					"using qccx arrays and integers. If just simple arrays "
+					"are being used, then they should work, but if "
+					"internal.qc is used, they most definitely will NOT. To"
+					"allow these progs to be used, set pr_boundscheck to 1.";
+				goto error;
+			}
 			break;
 	}
 	return;
@@ -1255,7 +1274,10 @@ PR_Check_Opcodes (progs_t *pr)
 		&& pr->fields.think != -1 && pr->fields.frame != -1)
 		state_ok = 1;
 
-	if (!pr_boundscheck->int_val) {
+	//FIXME need to decide if I really want to always do static bounds checking
+	// the only problem is that it slows progs load a little, but it's the only
+	// way to check for qccx' evil
+	if (0 && !pr_boundscheck->int_val) {
 		for (i = 0, st = pr->pr_statements; i < pr->progs->numstatements;
 			 st++, i++) {
 			op = PR_Opcode (st->op);