From 91f10abc65741b17a42c75b43c4a517b2372e0df Mon Sep 17 00:00:00 2001
From: dwarning <dwarning>
Date: Mon, 5 Jan 2009 21:31:45 +0000
Subject: [PATCH] small polish regarding HAVE_DECL_XXX macros

---
 src/include/missing_math.h | 11 +++++------
 src/maths/misc/isinf.c     | 40 +++++++++++++++++---------------------
 src/maths/misc/isnan.c     | 28 +++++++++++++-------------
 3 files changed, 37 insertions(+), 42 deletions(-)

diff --git a/src/include/missing_math.h b/src/include/missing_math.h
index 43d47585f..dd43bb7b9 100644
--- a/src/include/missing_math.h
+++ b/src/include/missing_math.h
@@ -2,7 +2,6 @@
 Copyright 1999 Emmanuel Rouat
 **********/
 
-
 /* Decl. for missing maths functions, if any */
 
 #ifndef MISSING_MATH_H_INCLUDED
@@ -26,23 +25,23 @@ extern double scalb(double, double);
 extern double scalbn(double, int);
 #endif
 
-#ifndef HAVE_DECL_ISNAN
+#if !HAVE_DECL_ISNAN
 #ifndef HAVE_ISNAN
 extern int isnan(double);
 #endif
 #endif
 
-#if (HAVE_DECL_ISINF < 1)
+#if !HAVE_DECL_ISINF
 #ifndef HAVE_ISINF
-#if defined(HAVE_FINITE) && ((HAVE_DECL_ISNAN < 1) || defined (HAVE_ISNAN))
+#if defined(HAVE_FINITE) && (HAVE_DECL_ISNAN || defined (HAVE_ISNAN))
 #define isinf(x) (!finite(x) && !isnan(x))
 #else
 #ifdef HAVE_IEEEFP_H
-    extern int isinf(double);
+extern int isinf(double);
 #endif
 #endif
 #else  /* HAVE_ISINF */
-  extern int isinf(double);
+extern int isinf(double);
 #endif /* HAVE_ISINF */
 #endif /* HAVE_DECL_ISINF */
 
diff --git a/src/maths/misc/isinf.c b/src/maths/misc/isinf.c
index bf73b4001..2bc497885 100644
--- a/src/maths/misc/isinf.c
+++ b/src/maths/misc/isinf.c
@@ -1,35 +1,31 @@
 #include "ngspice.h"
 
-#if (HAVE_DECL_ISINF < 1)
-
+#if !HAVE_DECL_ISINF
 #ifndef HAVE_ISINF
-
 #ifdef HAVE_IEEEFP_H
 
-  int isinf(double x) { return !finite(x) && x==x; }
+int isinf(double x) { return !finite(x) && x==x; }
 
 #else /* HAVE_IEEEFP_H */
 
-  /* this is really ugly - but it is a emergency case */
-  
-  static int
-  isinf(double x)
-  {
-      volatile double a = x;
-  
-      if (a > DBL_MAX)
-          return 1;
-      if (a < -DBL_MAX)
-          return -1;
-      return 0;
-  }
+/* this is really ugly - but it is a emergency case */
+
+static int
+isinf (const double x)
+{
+  double y = x - x;
+  int s = (y != y);
+
+  if (s && x > 0)
+    return +1;
+  else if (s && x < 0)
+    return -1;
+  else
+    return 0;
+}
 
 #endif /* HAVE_IEEEFP_H */
-
 #else /* HAVE_ISINF */
-
-  int Dummy_Symbol_5;
-
+int Dummy_Symbol_5;
 #endif /* HAVE_ISINF */
-
 #endif /* HAVE_DECL_ISINF */
diff --git a/src/maths/misc/isnan.c b/src/maths/misc/isnan.c
index ea6d349b4..e30ccab0d 100644
--- a/src/maths/misc/isnan.c
+++ b/src/maths/misc/isnan.c
@@ -1,45 +1,45 @@
 #include "ngspice.h"
 
-#if (HAVE_DECL_ISNAN < 1)
+#if !HAVE_DECL_ISNAN
 #ifndef HAVE_ISNAN
 
 /* isnan (originally) for SOI devices in MINGW32  hvogt (dev.c) */
 union ieee754_double
 {
-	double d;
-	
-	/* This is the IEEE 754 double-precision format.  */
-	struct
-	{
+  double d;
+  
+  /* This is the IEEE 754 double-precision format.  */
+  struct
+  {
     /* Together these comprise the mantissa.  */
     unsigned int mantissa1:32;
     unsigned int mantissa0:20;
     unsigned int exponent:11;
     unsigned int negative:1;
-	} ieee;
-	struct
-	{
+  } ieee;
+  struct
+  {
     /* Together these comprise the mantissa.  */
     unsigned int mantissa1:32;
     unsigned int mantissa0:19;
     unsigned int quiet_nan:1;
     unsigned int exponent:11;
     unsigned int negative:1;
-	} ieee_nan;
+  } ieee_nan;
 };
 
 int
 isnan(double value)
 {
   union ieee754_double u;
-	
+
   u.d = value;
-	
+
   /* IEEE 754 NaN's have the maximum possible
-		exponent and a nonzero mantissa.  */
+                exponent and a nonzero mantissa.  */
   return ((u.ieee.exponent & 0x7ff) == 0x7ff &&
           (u.ieee.mantissa0 != 0 || u.ieee.mantissa1 != 0));
-	
+
 }
 
 /*