Better handling of nan/infinity. Previously, these weren't working on Windows in config strings.

dtool/src/dtoolbase/cmath.I

@@ -365,12 +365,25 @@ cpow(int x, int y) {
 INLINE bool
 cnan(double v) {
 #ifndef _WIN32
-  return (std::isnan(v) != 0);
+  return std::isnan(v);
 #else
   return (_isnan(v) != 0);
 #endif
 }
 
+////////////////////////////////////////////////////////////////////
+//     Function: cinf
+//  Description:
+////////////////////////////////////////////////////////////////////
+INLINE bool
+cinf(double v) {
+#ifndef _WIN32
+  return std::isinf(v);
+#else
+  return (_isnan(v) == 0 && _finite(v) == 0);
+#endif
+}
+
 ////////////////////////////////////////////////////////////////////
 //     Function: make_nan
 //  Description:
@@ -380,7 +393,7 @@ make_nan(float) {
 #ifndef _WIN32
   return nanf("");
 #else
-  return numeric_limits<float>::quiet_NaN();
+  return std::numeric_limits<float>::quiet_NaN();
 #endif
 }
 
@@ -393,10 +406,27 @@ make_nan(double) {
 #ifndef _WIN32
   return nan("");
 #else
-  return numeric_limits<double>::quiet_NaN();
+  return std::numeric_limits<double>::quiet_NaN();
 #endif
 }
 
+////////////////////////////////////////////////////////////////////
+//     Function: make_inf
+//  Description:
+////////////////////////////////////////////////////////////////////
+INLINE float
+make_inf(float) {
+  return std::numeric_limits<float>::infinity();
+}
+
+////////////////////////////////////////////////////////////////////
+//     Function: make_inf
+//  Description:
+////////////////////////////////////////////////////////////////////
+INLINE double
+make_inf(double) {
+  return std::numeric_limits<double>::infinity();
+}
 
 ////////////////////////////////////////////////////////////////////
 //     Function: cmod

dtool/src/dtoolbase/cmath.h

@@ -68,13 +68,17 @@ INLINE int cpow(int x, int y);
 // or infinity.
 INLINE bool cnan(double v);
 
-// Returns NaN.
+// Returns true if the number is infinity.
+INLINE bool cinf(double v);
+
+// Return NaN and infinity, respectively.
 INLINE float make_nan(float);
 INLINE double make_nan(double);
+INLINE float make_inf(float);
+INLINE double make_inf(double);
 
 INLINE int cmod(int x, int y);
 
 #include "cmath.I"
 
 #endif
-

dtool/src/dtoolbase/pstrtod.cxx

@@ -17,6 +17,9 @@
 #include <ctype.h>
 #include <math.h>
 
+#ifdef _WIN32
+#define strncasecmp _strnicmp
+#endif
 
 ////////////////////////////////////////////////////////////////////
 //     Function: pstrtod
@@ -45,11 +48,43 @@ pstrtod(const char *nptr, char **endptr) {
   double value = 0.0;
 
   if (isalpha(*p)) {
-    // For special cases like "inf" and "nan", pass these up to the
+    // Windows' implementation of strtod doesn't support "inf" or
-    // system implementation of strtod.
+    // "nan", so check for those here.
+    if (strncasecmp(p, "inf", 3) == 0) {
+      p += 3;
+      if (strncasecmp(p, "inity", 5) == 0) {
+        p += 5;
+      }
+      value = std::numeric_limits<double>::infinity();
+
+    } else if (strncasecmp(p, "nan", 3) == 0) {
+      p += 3;
+
+      if (*p == 's' || *p == 'S') {
+        value = std::numeric_limits<double>::signaling_NaN();
+        ++p;
+      } else {
+        if (*p == 'q' || *p == 'Q') {
+          ++p;
+        }
+        value = std::numeric_limits<double>::quiet_NaN();
+      }
+
+      // It is optionally possible to include a character sequence
+      // between parentheses after "nan", to be passed to the new
+      // nan() function.  Since it isn't supported universally, we
+      // will only accept a pair of empty parentheses.
+      if (strncmp(p, "()", 2) == 0) {
+        p += 2;
+      }
+
+    } else {
+      // Pass it up to the system implementation of strtod;
+      // perhaps it knows how to deal with this string.
       return strtod(nptr, endptr);
     }
 
+  } else {
     // Start reading decimal digits to the left of the decimal point.
     bool found_digits = false;
     while (isdigit(*p)) {
@@ -101,6 +136,7 @@ pstrtod(const char *nptr, char **endptr) {
         value *= pow(evalue, 10.0);
       }
     }
+  }
 
   if (sign == '-') {
     value = -value;