From 2f8b38266ca4c0fadce4b0a62a436869978a9fa6 Mon Sep 17 00:00:00 2001
From: Stefano Fiorentino <stefanofiorentino@users.noreply.github.com>
Date: Fri, 12 Feb 2016 11:45:56 +0100
Subject: [PATCH] address the double to json accounting for large double
 (thousands, millions, billions) and avoid "negative mantissa length"

---
 src/lib_json/json_writer.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/lib_json/json_writer.cpp b/src/lib_json/json_writer.cpp
index bce273a..1ac1462 100644
--- a/src/lib_json/json_writer.cpp
+++ b/src/lib_json/json_writer.cpp
@@ -145,7 +145,14 @@ std::string valueToString(double value, bool useSpecialFloats, unsigned int prec
   if (length<1) length=1;
 
   char formatString[6];
-  sprintf(formatString, "%%.%dg", precision-length);
+  if (length<precision)
+  {
+	  sprintf(formatString, "%%.%dg", precision-length);
+  }
+  else
+  {
+	  sprintf(formatString, "%%g");
+  }
 
   // Print into the buffer. We need not request the alternative representation
   // that always has a decimal point because JSON doesn't distingish the