From a35ee9894d8a59c302d2fa32f859a76e69ee7410 Mon Sep 17 00:00:00 2001
From: janwas <jan@wildfiregames.com>
Date: Fri, 5 May 2006 05:54:00 +0000
Subject: [PATCH] # add strict VSrc validation in OpenAL interface to track
 down bug - required adding C99 insnan() implementation, along with fpclassify

This was SVN commit r3850.
---
 source/lib/res/sound/snd_mgr.cpp | 11 +++++++++++
 source/lib/sysdep/ia32.h         | 10 ++++++++++
 source/lib/sysdep/ia32_asm.asm   | 30 ++++++++++++++++++++++++++++--
 source/lib/sysdep/sysdep.cpp     | 15 +++++++++++++++
 source/lib/sysdep/sysdep.h       | 16 ++++++++++++++++
 5 files changed, 80 insertions(+), 2 deletions(-)

diff --git a/source/lib/res/sound/snd_mgr.cpp b/source/lib/res/sound/snd_mgr.cpp
index afabeb6485..91a2259da6 100644
--- a/source/lib/res/sound/snd_mgr.cpp
+++ b/source/lib/res/sound/snd_mgr.cpp
@@ -1827,11 +1827,22 @@ static void vsrc_latch(VSrc* vs)
 	if(!vs->al_src)
 		return;
 
+#ifndef NDEBUG
+	// paranoid value checking; helps determine which parameter is
+	// the problem when the below AL_CHECK fails.
+	debug_assert(!isnan(vs->pos[0]) && !isnan(vs->pos[1]) && !isnan(vs->pos[2]));
+	debug_assert(vs->relative == AL_TRUE || vs->relative == AL_FALSE);
+	debug_assert(!isnan(vs->gain));
+	debug_assert(!isnan(vs->pitch) && vs->pitch > 0.0f);
+	debug_assert(vs->loop == AL_TRUE || vs->loop == AL_FALSE);
+#endif
+
 	alSourcefv(vs->al_src, AL_POSITION,        vs->pos);
 	alSourcei (vs->al_src, AL_SOURCE_RELATIVE, vs->relative);
 	alSourcef (vs->al_src, AL_GAIN,            vs->gain);
 	alSourcef (vs->al_src, AL_PITCH,           vs->pitch);
 	alSourcei (vs->al_src, AL_LOOPING,         vs->loop);
+
 	AL_CHECK;
 }
 
diff --git a/source/lib/sysdep/ia32.h b/source/lib/sysdep/ia32.h
index 02facc107f..cb118ad466 100644
--- a/source/lib/sysdep/ia32.h
+++ b/source/lib/sysdep/ia32.h
@@ -54,6 +54,16 @@ extern i32 ia32_i32_from_float(float f);
 extern i32 ia32_i32_from_double(double d);
 extern i64 ia32_i64_from_double(double d);
 
+// fpclassify return values
+#define IA32_FP_NAN       0x0100
+#define IA32_FP_NORMAL    0x0400
+#define IA32_FP_INFINITE  (IA32_FP_NAN | IA32_FP_NORMAL)
+#define IA32_FP_ZERO      0x4000
+#define IA32_FP_SUBNORMAL (IA32_FP_NORMAL | IA32_FP_ZERO)
+
+extern uint ia32_fpclassify(double d);
+extern uint ia32_fpclassifyf(float f);
+
 extern void* ia32_memcpy(void* dst, const void* src, size_t nbytes);	// asm
 
 
diff --git a/source/lib/sysdep/ia32_asm.asm b/source/lib/sysdep/ia32_asm.asm
index afef8e19d0..a81225b338 100644
--- a/source/lib/sysdep/ia32_asm.asm
+++ b/source/lib/sysdep/ia32_asm.asm
@@ -503,10 +503,10 @@ db		0xf0							; LOCK prefix
 
 
 ;-------------------------------------------------------------------------------
-; misc
+; FPU
 ;-------------------------------------------------------------------------------
 
-; extern "C" uint __cdecl ia32_control87(uint new_cw, uint mask)
+; extern "C" uint __cdecl ia32_control87(uint new_cw, uint mask);
 global sym(ia32_control87)
 sym(ia32_control87):
 	push	eax
@@ -525,6 +525,32 @@ sym(ia32_control87):
 	ret
 
 
+; possible IA-32 FPU control word flags after FXAM: NAN|NORMAL|ZERO
+FP_CLASSIFY_MASK	equ 0x4500
+
+; extern "C" uint __cdecl ia32_fpclassify(double d);
+global sym(ia32_fpclassify)
+sym(ia32_fpclassify):
+	fld		qword [esp+4]
+	fxam
+	fnstsw	ax
+	and		eax, FP_CLASSIFY_MASK
+	ret
+
+; extern "C" uint __cdecl ia32_fpclassifyf(float f);
+global sym(ia32_fpclassifyf)
+sym(ia32_fpclassifyf):
+	fld		dword [esp+4]
+	fxam
+	fnstsw	ax
+	and		eax, FP_CLASSIFY_MASK
+	ret
+
+
+;-------------------------------------------------------------------------------
+; misc
+;-------------------------------------------------------------------------------
+
 ; write the current execution state (e.g. all register values) into
 ; (Win32::CONTEXT*)pcontext (defined as void* to avoid dependency).
 ; optimized for size; this must be straight asm because __declspec(naked)
diff --git a/source/lib/sysdep/sysdep.cpp b/source/lib/sysdep/sysdep.cpp
index da6a323078..27b1bcf0a7 100644
--- a/source/lib/sysdep/sysdep.cpp
+++ b/source/lib/sysdep/sysdep.cpp
@@ -51,6 +51,21 @@ float fmaxf(float a, float b)
 	return (a > b)? a : b;
 }
 
+uint fpclassify(double d)
+{
+	// really sucky stub implementation; doesn't attempt to cover all cases.
+
+	if(d != d)
+		return IA32_FP_NAN;
+	else
+		return IA32_FP_NORMAL;
+}
+
+uint fpclassifyf(float f)
+{
+	return fpclassify((double)f);
+}
+
 #endif
 
 #endif	// #if !HAVE_C99
diff --git a/source/lib/sysdep/sysdep.h b/source/lib/sysdep/sysdep.h
index f0dcc8a6b1..3b2f1a5654 100644
--- a/source/lib/sysdep/sysdep.h
+++ b/source/lib/sysdep/sysdep.h
@@ -101,13 +101,29 @@ extern void* alloca(size_t size);
 #  define rint ia32_rint
 #  define fminf ia32_fminf
 #  define fmaxf ia32_fmaxf
+
+#  define FP_NAN       IA32_FP_NAN
+#  define FP_NORMAL    IA32_FP_NORMAL
+#  define FP_INFINITE  (FP_NAN | FP_NORMAL)
+#  define FP_ZERO      IA32_FP_ZERO
+#  define FP_SUBNORMAL (FP_NORMAL | FP_ZERO)
+#  define fpclassify ia32_fpclassify
 // .. portable C emulation
 # else
    extern float rintf(float f);
    extern double rint(double d);
    extern float fminf(float a, float b);
    extern float fmaxf(float a, float b);
+
+#  define FP_NAN       1
+#  define FP_NORMAL    2
+#  define FP_INFINITE  (FP_NAN | FP_NORMAL)
+#  define FP_ZERO      4
+#  define FP_SUBNORMAL (FP_NORMAL | FP_ZERO)
+   extern uint fpclassify(double d);
 # endif
+
+# define isnan(d) (fpclassify(d) == FP_NAN)
 #endif
 
 // finite: return 0 iff the given double is infinite or NaN.