VMDouble: Fix memory leaks in toString() and parseDouble()

Function _dtoa() from fdlibm/dtoa.c was failing to release memory
allocated during double->string conversion. A similar problem was
also present in parseDoubleFromChars() from java_lang_VMDouble.c.
This caused leaks in VMDouble.toString() and .parseDouble().

Fixed by adding a new function _reclaim_reent, ported from current
newlib.

Fixes #34 (BZ#29263)

Author: guillerodriguez

native/fdlibm/dtoa.c

@@ -898,23 +898,11 @@ _DEFUN (_dtoa,
 {
   struct _Jv_reent reent;
   char *p;
-  int i;
 
   memset (&reent, 0, sizeof reent);
 
   p = _dtoa_r (&reent, _d, mode, ndigits, decpt, sign, rve, float_type);
   strcpy (buf, p);
 
-  for (i = 0; i < reent._result_k; ++i)
-    {
-      struct _Jv_Bigint *l = reent._freelist[i];
-      while (l)
-	{
-	  struct _Jv_Bigint *next = l->_next;
-	  free (l);
-	  l = next;
-	}
-    }
-  if (reent._freelist)
-    free (reent._freelist);
+  _reclaim_reent (&reent);
 }

native/fdlibm/mprec.c

@@ -95,6 +95,7 @@
 
 #define _REENT_CHECK_MP(x)
 #define _REENT_MP_FREELIST(x) ((x)->_freelist)
+#define _REENT_MP_RESULT(x) ((x)->_result)
 #define _REENT_MP_P5S(x) ((x)->_p5s)
 
 typedef unsigned long __ULong;
@@ -108,6 +109,42 @@ mprec_calloc (void *ignore, size_t x1, size_t x2)
   return result;
 }
 
+void
+_reclaim_reent (struct _reent *ptr)
+{
+  if (_REENT_MP_FREELIST(ptr))
+    {
+      int i;
+      for (i = 0; i < ptr->_max_k; i++)
+        {
+          struct _Bigint *thisone, *nextone;
+
+          nextone = _REENT_MP_FREELIST(ptr)[i];
+          while (nextone)
+            {
+              thisone = nextone;
+              nextone = nextone->_next;
+              free (thisone);
+            }
+        }
+
+      free (_REENT_MP_FREELIST(ptr));
+    }
+  if (_REENT_MP_RESULT(ptr))
+    free (_REENT_MP_RESULT(ptr));
+  if (_REENT_MP_P5S(ptr))
+    {
+      struct _Bigint *thisone, *nextone;
+      nextone = _REENT_MP_P5S(ptr);
+      while (nextone)
+       {
+         thisone = nextone;
+         nextone = nextone->_next;
+         free (thisone);
+       }
+    }
+}
+
 _Bigint *
 _DEFUN (Balloc, (ptr, k), struct _reent *ptr _AND int k)
 {

native/fdlibm/mprec.h

@@ -343,13 +343,15 @@ typedef struct _Jv_Bigint _Jv_Bigint;
 #define _dtoa _Jv_dtoa
 #define _dtoa_r _Jv_dtoa_r
 #define _strtod_r _Jv_strtod_r
+#define _reclaim_reent _Jv_reclaim_reent
 
 extern double _EXFUN(_strtod_r, (struct _Jv_reent *ptr, const char *s00, char **se));
 extern char* _EXFUN(_dtoa_r, (struct _Jv_reent *ptr, double d,
 			      int mode, int ndigits, int *decpt, int *sign,
 			      char **rve, int float_type));
 void _EXFUN(_dtoa, (double d, int mode, int ndigits, int *decpt, int *sign,
 		    char **rve, char *buf, int float_type));
+void _EXFUN(_reclaim_reent, (struct _Jv_reent *ptr));
 
 double 		_EXFUN(ulp,(double x));
 double		_EXFUN(b2d,(_Jv_Bigint *a , int *e));

native/jni/java-lang/java_lang_VMDouble.c

@@ -224,6 +224,8 @@ parseDoubleFromChars(JNIEnv * env, const char * buf)
 
       val = _strtod_r (&reent, p, &endptr);
 
+      _reclaim_reent (&reent);
+
 #ifdef DEBUG
       fprintf (stderr, "java.lang.VMDouble.parseDouble val = %g\n", val);
       fprintf (stderr, "java.lang.VMDouble.parseDouble %p != %p ???\n",