Merge pull request #1132 from mattleibow/bugfix-20925

[mono.git] / mono / metadata / sysmath.c

diff --git a/mono/metadata/sysmath.c b/mono/metadata/sysmath.c
index 6627009eebb98644ad62238f196cb4bbb7d41e1b..c5943b44cc908340346131c61e31c353e1a2b190 100644 (file)
--- a/mono/metadata/sysmath.c
+++ b/mono/metadata/sysmath.c
@@ -1,5 +1,12 @@
-/* math.c - these are based on bob smith's csharp routines */
-
+/*
+ * sysmath.c: these are based on bob smith's csharp routines 
+ *
+ * Author:
+ *     Mono Project (http://www.mono-project.com)
+ *
+ * Copyright 2001-2003 Ximian, Inc (http://www.ximian.com)
+ * Copyright 2004-2009 Novell, Inc (http://www.novell.com)
+ */
 #define __USE_ISOC99
 #include <math.h>
 #include <mono/metadata/sysmath.h>
@@ -48,23 +55,41 @@ gdouble ves_icall_System_Math_Round (gdouble x) {
        return int_part;
 }
 
-gdouble ves_icall_System_Math_Round2 (gdouble value, gint32 digits) {
-       double p, int_part, dec_part;
+gdouble ves_icall_System_Math_Round2 (gdouble value, gint32 digits, gboolean away_from_zero) {
+#if !defined (HAVE_ROUND) || !defined (HAVE_RINT)
+       double int_part, dec_part;
+#endif
+       double p;
+
        MONO_ARCH_SAVE_REGS;
        if (value == HUGE_VAL)
                return HUGE_VAL;
        if (value == -HUGE_VAL)
                return -HUGE_VAL;
-       if (digits == 0)
-               return ves_icall_System_Math_Round(value);
        p = pow(10, digits);
+#if defined (HAVE_ROUND) && defined (HAVE_RINT)
+       if (away_from_zero)
+               return round (value * p) / p;
+       else
+               return rint (value * p) / p;
+#else
        dec_part = modf (value, &int_part);
        dec_part *= 1000000000000000ULL;
-       dec_part = floor(dec_part);
+       if (away_from_zero && dec_part > 0)
+               dec_part = ceil (dec_part);
+       else
+               dec_part = floor (dec_part);
        dec_part /= (1000000000000000ULL / p);
-       dec_part = ves_icall_System_Math_Round(dec_part);
+       if (away_from_zero) {
+               if (dec_part > 0)
+                       dec_part = floor (dec_part + 0.5);
+               else
+                       dec_part = ceil (dec_part - 0.5);
+       } else
+               dec_part = ves_icall_System_Math_Round (dec_part);
        dec_part /= p;
-       return int_part + dec_part;
+       return ves_icall_System_Math_Round ((int_part + dec_part) * p) / p;
+#endif
 }
 
 gdouble