Added custom implementation of ftoa (issues #266, #267, #269 and #270)

CHANGELOG.md

@@ -4,7 +4,8 @@ ArduinoJson: change log
 HEAD
 ----
 
-* Fix `unsigned long` printed as `signed long` (issue #170)
+* Added custom implementation of `ftoa` (issues #266, #267, #269 and #270)
+* Fixed `unsigned long` printed as `signed long` (issue #170)
 
 v5.2.0
 ------

include/ArduinoJson/Arduino/Print.hpp

@@ -9,19 +9,8 @@
 
 #ifndef ARDUINO
 
-#include "../Internals/JsonFloat.hpp"
-#include "../Internals/JsonInteger.hpp"
-
 #include <stddef.h>
 #include <stdint.h>
-#include <stdio.h>
-
-#if defined(_MSC_VER) && _MSC_VER <= 1800
-// snprintf has been added in Visual Studio 2015
-#define ARDUINOJSON_SNPRINTF _snprintf
-#else
-#define ARDUINOJSON_SNPRINTF snprintf
-#endif
 
 // This class reproduces Arduino's Print class
 class Print {
@@ -38,41 +27,6 @@ class Print {
     return n;
   }
 
-  size_t print(ArduinoJson::Internals::JsonFloat value, int digits = 2) {
-    char tmp[32];
-
-    // https://github.com/arduino/Arduino/blob/db8cbf24c99dc930b9ccff1a43d018c81f178535/hardware/arduino/sam/cores/arduino/Print.cpp#L220
-    bool isBigDouble = value > 4294967040.0 || value < -4294967040.0;
-
-    if (isBigDouble) {
-      // Arduino's implementation prints "ovf"
-      // We prefer using the scientific notation, since we have sprintf
-      ARDUINOJSON_SNPRINTF(tmp, sizeof(tmp), "%g", value);
-    } else {
-      // Here we have the exact same output as Arduino's implementation
-      ARDUINOJSON_SNPRINTF(tmp, sizeof(tmp), "%.*f", digits, value);
-    }
-
-    return print(tmp);
-  }
-
-  size_t print(ArduinoJson::Internals::JsonUInt value) {
-    char buffer[22];
-
-    uint8_t i = 0;
-    do {
-      buffer[i++] = static_cast<char>(value % 10 + '0');
-      value /= 10;
-    } while (value);
-
-    size_t n = 0;
-    while (i > 0) {
-      n += write(buffer[--i]);
-    }
-
-    return n;
-  }
-
   size_t println() { return write('\r') + write('\n'); }
 };
 

include/ArduinoJson/Internals/JsonWriter.hpp

@@ -8,6 +8,9 @@
 #pragma once
 
 #include "../Arduino/Print.hpp"
+#include "../Polyfills/isNaN.hpp"
+#include "../Polyfills/isInfinity.hpp"
+#include "../Polyfills/normalize.hpp"
 #include "Encoding.hpp"
 #include "ForceInline.hpp"
 #include "JsonFloat.hpp"
@@ -63,10 +66,70 @@ class JsonWriter {
     }
   }
 
-  void writeInteger(JsonUInt value) { _length += _sink.print(value); }
+  void writeFloat(JsonFloat value, int digits = 2) {
+    if (Polyfills::isNaN(value)) return writeRaw("NaN");
 
-  void writeFloat(JsonFloat value, uint8_t decimals) {
-    _length += _sink.print(value, decimals);
+    if (value < 0.0) {
+      writeRaw('-');
+      value = -value;
+    }
+
+    if (Polyfills::isInfinity(value)) return writeRaw("Infinity");
+
+    short powersOf10;
+    if (value > 1000 || value < 0.001) {
+      powersOf10 = Polyfills::normalize(value);
+    } else {
+      powersOf10 = 0;
+    }
+
+    // Round correctly so that print(1.999, 2) prints as "2.00"
+    JsonFloat rounding = 0.5;
+    for (uint8_t i = 0; i < digits; ++i) rounding /= 10.0;
+
+    value += rounding;
+
+    // Extract the integer part of the value and print it
+    JsonUInt int_part = static_cast<JsonUInt>(value);
+    JsonFloat remainder = value - static_cast<JsonFloat>(int_part);
+    writeInteger(int_part);
+
+    // Print the decimal point, but only if there are digits beyond
+    if (digits > 0) {
+      writeRaw('.');
+    }
+
+    // Extract digits from the remainder one at a time
+    while (digits-- > 0) {
+      remainder *= 10.0;
+      JsonUInt toPrint = JsonUInt(remainder);
+      writeInteger(JsonUInt(remainder));
+      remainder -= static_cast<JsonFloat>(toPrint);
+    }
+
+    if (powersOf10 < 0) {
+      writeRaw("e-");
+      writeInteger(-powersOf10);
+    }
+
+    if (powersOf10 > 0) {
+      writeRaw('e');
+      writeInteger(powersOf10);
+    }
+  }
+
+  void writeInteger(JsonUInt value) {
+    char buffer[22];
+
+    uint8_t i = 0;
+    do {
+      buffer[i++] = static_cast<char>(value % 10 + '0');
+      value /= 10;
+    } while (value);
+
+    while (i > 0) {
+      writeRaw(buffer[--i]);
+    }
   }
 
   void writeRaw(const char *s) { _length += _sink.print(s); }

include/ArduinoJson/Internals/Parse.hpp

@@ -29,6 +29,11 @@ inline long parse<long>(const char *s) {
   return strtol(s, NULL, 10);
 }
 
+template <>
+inline unsigned long parse<unsigned long>(const char *s) {
+  return strtoul(s, NULL, 10);
+}
+
 template <>
 inline int parse<int>(const char *s) {
   return atoi(s);
@@ -39,6 +44,11 @@ template <>
 inline long long parse<long long>(const char *s) {
   return strtoll(s, NULL, 10);
 }
+
+template <>
+inline unsigned long long parse<unsigned long long>(const char *s) {
+  return strtoull(s, NULL, 10);
+}
 #endif
 
 #if ARDUINOJSON_USE_INT64
@@ -46,6 +56,11 @@ template <>
 inline __int64 parse<__int64>(const char *s) {
   return _strtoi64(s, NULL, 10);
 }
+
+template <>
+inline unsigned __int64 parse<unsigned __int64>(const char *s) {
+  return _strtoui64(s, NULL, 10);
+}
 #endif
 }
 }

include/ArduinoJson/JsonVariant.hpp

@@ -63,23 +63,33 @@ class JsonVariant : public JsonVariantBase<JsonVariant> {
   }
 
   // Create a JsonVariant containing an integer value.
-  // JsonVariant(short)
-  // JsonVariant(int)
-  // JsonVariant(long)
+  // JsonVariant(signed short)
+  // JsonVariant(signed int)
+  // JsonVariant(signed long)
   template <typename T>
   FORCE_INLINE JsonVariant(
-      T value,
-      typename TypeTraits::EnableIf<TypeTraits::IsIntegral<T>::value>::type * =
-          0) {
+      T value, typename TypeTraits::EnableIf<
+                   TypeTraits::IsSignedIntegral<T>::value>::type * = 0) {
     using namespace Internals;
     if (value >= 0) {
       _type = JSON_POSITIVE_INTEGER;
-      _content.asInteger = static_cast<JsonInteger>(value);
+      _content.asInteger = static_cast<JsonUInt>(value);
     } else {
       _type = JSON_NEGATIVE_INTEGER;
-      _content.asInteger = static_cast<JsonInteger>(-value);
+      _content.asInteger = static_cast<JsonUInt>(-value);
     }
   }
+  // JsonVariant(unsigned short)
+  // JsonVariant(unsigned int)
+  // JsonVariant(unsigned long)
+  template <typename T>
+  FORCE_INLINE JsonVariant(
+      T value, typename TypeTraits::EnableIf<
+                   TypeTraits::IsUnsignedIntegral<T>::value>::type * = 0) {
+    using namespace Internals;
+    _type = JSON_POSITIVE_INTEGER;
+    _content.asInteger = static_cast<JsonUInt>(value);
+  }
 
   // Create a JsonVariant containing a string.
   FORCE_INLINE JsonVariant(const char *value);
@@ -95,15 +105,26 @@ class JsonVariant : public JsonVariantBase<JsonVariant> {
 
   // Get the variant as the specified type.
   //
-  // short as<short>() const;
-  // int as<int>() const;
-  // long as<long>() const;
+  // short as<signed short>() const;
+  // int as<signed int>() const;
+  // long as<signed long>() const;
   template <typename T>
-  const typename TypeTraits::EnableIf<TypeTraits::IsIntegral<T>::value, T>::type
+  const typename TypeTraits::EnableIf<TypeTraits::IsSignedIntegral<T>::value,
+                                      T>::type
   as() const {
     return static_cast<T>(asInteger());
   }
   //
+  // short as<unsigned short>() const;
+  // int as<unsigned int>() const;
+  // long as<unsigned long>() const;
+  template <typename T>
+  const typename TypeTraits::EnableIf<TypeTraits::IsUnsignedIntegral<T>::value,
+                                      T>::type
+  as() const {
+    return static_cast<T>(asUnsignedInteger());
+  }
+  //
   // double as<double>() const;
   // float as<float>() const;
   template <typename T>
@@ -247,9 +268,16 @@ class JsonVariant : public JsonVariantBase<JsonVariant> {
   JsonObject &asObject() const;
 
  private:
+  // It's not allowed to store a char
+  template <typename T>
+  FORCE_INLINE JsonVariant(T value,
+                           typename TypeTraits::EnableIf<
+                               TypeTraits::IsSame<T, char>::value>::type * = 0);
+
   String toString() const;
   Internals::JsonFloat asFloat() const;
   Internals::JsonInteger asInteger() const;
+  Internals::JsonUInt asUnsignedInteger() const;
   bool isBoolean() const;
   bool isFloat() const;
   bool isInteger() const;

include/ArduinoJson/JsonVariant.ipp

@@ -55,7 +55,7 @@ inline Internals::JsonInteger JsonVariant::asInteger() const {
     case JSON_BOOLEAN:
       return _content.asInteger;
     case JSON_NEGATIVE_INTEGER:
-      return -_content.asInteger;
+      return -static_cast<Internals::JsonInteger>(_content.asInteger);
     case JSON_STRING:
     case JSON_UNPARSED:
       if (!_content.asString) return 0;
@@ -66,6 +66,25 @@ inline Internals::JsonInteger JsonVariant::asInteger() const {
   }
 }
 
+inline Internals::JsonUInt JsonVariant::asUnsignedInteger() const {
+  using namespace Internals;
+  switch (_type) {
+    case JSON_UNDEFINED:
+      return 0;
+    case JSON_POSITIVE_INTEGER:
+    case JSON_BOOLEAN:
+    case JSON_NEGATIVE_INTEGER:
+      return _content.asInteger;
+    case JSON_STRING:
+    case JSON_UNPARSED:
+      if (!_content.asString) return 0;
+      if (!strcmp("true", _content.asString)) return 1;
+      return parse<Internals::JsonUInt>(_content.asString);
+    default:
+      return static_cast<Internals::JsonUInt>(_content.asFloat);
+  }
+}
+
 #if ARDUINOJSON_ENABLE_STD_STREAM
 inline std::ostream &operator<<(std::ostream &os, const JsonVariant &source) {
   return source.printTo(os);

include/ArduinoJson/Polyfills/isInfinity.hpp

@@ -0,0 +1,45 @@
+// Copyright Benoit Blanchon 2014-2016
+// MIT License
+//
+// Arduino JSON library
+// https://github.com/bblanchon/ArduinoJson
+// If you like this project, please add a star!
+
+#pragma once
+
+// If Visual Studo <= 2012
+#if defined(_MSC_VER) && _MSC_VER <= 1700
+#include <float.h>
+#else
+#include <math.h>
+#endif
+
+namespace ArduinoJson {
+namespace Polyfills {
+
+// If Visual Studo <= 2012
+#if defined(_MSC_VER) && _MSC_VER <= 1700
+template <typename T>
+bool isInfinity(T x) {
+  return !_finite(x);
+}
+#else
+template <typename T>
+bool isInfinity(T x) {
+  return isinf(x);
+}
+
+#ifdef __GLIBC__
+template <>
+inline bool isInfinity<double>(double x) {
+  return isinfl(x);
+}
+
+template <>
+inline bool isInfinity<float>(float x) {
+  return isinff(x);
+}
+#endif
+#endif
+}
+}

include/ArduinoJson/Polyfills/isNaN.hpp

@@ -0,0 +1,46 @@
+// Copyright Benoit Blanchon 2014-2016
+// MIT License
+//
+// Arduino JSON library
+// https://github.com/bblanchon/ArduinoJson
+// If you like this project, please add a star!
+
+#pragma once
+
+// If Visual Studo <= 2012
+#if defined(_MSC_VER) && _MSC_VER <= 1700
+#include <float.h>
+#else
+#include <math.h>
+#endif
+
+namespace ArduinoJson {
+namespace Polyfills {
+
+// If Visual Studo <= 2012
+#if defined(_MSC_VER) && _MSC_VER <= 1700
+template <typename T>
+bool isNaN(T x) {
+  return _isnan(x) != 0;
+}
+#else
+template <typename T>
+bool isNaN(T x) {
+  return isnan(x);
+}
+
+#ifdef __GLIBC__
+template <>
+inline bool isNaN<double>(double x) {
+  return isnanl(x);
+}
+
+template <>
+inline bool isNaN<float>(float x) {
+  return isnanf(x);
+}
+#endif
+
+#endif
+}
+}

include/ArduinoJson/Polyfills/normalize.hpp

@@ -0,0 +1,47 @@
+// Copyright Benoit Blanchon 2014-2016
+// MIT License
+//
+// Arduino JSON library
+// https://github.com/bblanchon/ArduinoJson
+// If you like this project, please add a star!
+
+#pragma once
+
+namespace ArduinoJson {
+namespace Polyfills {
+
+#ifdef ARDUINO
+
+// on embedded platform, favor code size over speed
+
+template <typename T>
+short normalize(T& value) {
+  short powersOf10 = 0;
+  while (value && value < 1) {
+    powersOf10--;
+    value *= 10;
+  }
+  while (value > 10) {
+    powersOf10++;
+    value /= 10;
+  }
+  return powersOf10;
+}
+
+#else
+
+// on non-embedded platform, favor speed over code size
+
+template <typename T>
+short normalize(T& value) {
+  if (value == 0.0) return 0;
+
+  short powersOf10 = static_cast<short>(floor(log10(value)));
+  value /= pow(T(10), powersOf10);
+
+  return powersOf10;
+}
+
+#endif
+}
+}

include/ArduinoJson/TypeTraits/IsIntegral.hpp

@@ -9,8 +9,8 @@
 
 #include "../Configuration.hpp"
 #include "IsSame.hpp"
-
-#include <stdint.h>
+#include "IsSignedIntegral.hpp"
+#include "IsUnsignedIntegral.hpp"
 
 namespace ArduinoJson {
 namespace TypeTraits {
@@ -18,23 +18,8 @@ namespace TypeTraits {
 // A meta-function that returns true if T is an integral type.
 template <typename T>
 struct IsIntegral {
-  static const bool value = TypeTraits::IsSame<T, signed char>::value ||
-                            TypeTraits::IsSame<T, unsigned char>::value ||
-                            TypeTraits::IsSame<T, signed short>::value ||
-                            TypeTraits::IsSame<T, unsigned short>::value ||
-                            TypeTraits::IsSame<T, signed int>::value ||
-                            TypeTraits::IsSame<T, unsigned int>::value ||
-                            TypeTraits::IsSame<T, signed long>::value ||
-                            TypeTraits::IsSame<T, unsigned long>::value ||
-#if ARDUINOJSON_USE_LONG_LONG
-                            TypeTraits::IsSame<T, long long>::value ||
-                            TypeTraits::IsSame<T, unsigned long long>::value ||
-#endif
-
-#if ARDUINOJSON_USE_INT64
-                            TypeTraits::IsSame<T, __int64>::value ||
-                            TypeTraits::IsSame<T, unsigned __int64>::value ||
-#endif
+  static const bool value = TypeTraits::IsSignedIntegral<T>::value ||
+                            TypeTraits::IsUnsignedIntegral<T>::value ||
                             TypeTraits::IsSame<T, char>::value;
 };
 }

include/ArduinoJson/TypeTraits/IsSignedIntegral.hpp

@@ -0,0 +1,33 @@
+// Copyright Benoit Blanchon 2014-2016
+// MIT License
+//
+// Arduino JSON library
+// https://github.com/bblanchon/ArduinoJson
+// If you like this project, please add a star!
+
+#pragma once
+
+#include "../Configuration.hpp"
+#include "IsSame.hpp"
+
+namespace ArduinoJson {
+namespace TypeTraits {
+
+// A meta-function that returns true if T is an integral type.
+template <typename T>
+struct IsSignedIntegral {
+  static const bool value = TypeTraits::IsSame<T, signed char>::value ||
+                            TypeTraits::IsSame<T, signed short>::value ||
+                            TypeTraits::IsSame<T, signed int>::value ||
+                            TypeTraits::IsSame<T, signed long>::value ||
+#if ARDUINOJSON_USE_LONG_LONG
+                            TypeTraits::IsSame<T, signed long long>::value ||
+#endif
+
+#if ARDUINOJSON_USE_INT64
+                            TypeTraits::IsSame<T, signed __int64>::value ||
+#endif
+                            false;
+};
+}
+}

include/ArduinoJson/TypeTraits/IsUnsignedIntegral.hpp

@@ -0,0 +1,33 @@
+// Copyright Benoit Blanchon 2014-2016
+// MIT License
+//
+// Arduino JSON library
+// https://github.com/bblanchon/ArduinoJson
+// If you like this project, please add a star!
+
+#pragma once
+
+#include "../Configuration.hpp"
+#include "IsSame.hpp"
+
+namespace ArduinoJson {
+namespace TypeTraits {
+
+// A meta-function that returns true if T is an integral type.
+template <typename T>
+struct IsUnsignedIntegral {
+  static const bool value = TypeTraits::IsSame<T, unsigned char>::value ||
+                            TypeTraits::IsSame<T, unsigned short>::value ||
+                            TypeTraits::IsSame<T, unsigned int>::value ||
+                            TypeTraits::IsSame<T, unsigned long>::value ||
+#if ARDUINOJSON_USE_LONG_LONG
+                            TypeTraits::IsSame<T, unsigned long long>::value ||
+#endif
+
+#if ARDUINOJSON_USE_INT64
+                            TypeTraits::IsSame<T, unsigned __int64>::value ||
+#endif
+                            false;
+};
+}
+}

scripts/create-build-envs.sh

@@ -21,9 +21,9 @@ if [[ $(uname) == MINGW* ]]
 then
 	build-env "Make" "MinGW Makefiles"
 	build-env "SublimeText" "Sublime Text 2 - Ninja"
-	build-env "VisualStudio" "Visual Studio 12 2013"
+	build-env "VisualStudio" "Visual Studio 14 2015"
 else
 	build-env "SublimeText" "Sublime Text 2 - Ninja"
 	build-env "Make" "Unix Makefiles"
 	build-env "Xcode" "Xcode"
-fi
+fi

test/Issue67.cpp

@@ -1,48 +0,0 @@
-// Copyright Benoit Blanchon 2014-2016
-// MIT License
-//
-// Arduino JSON library
-// https://github.com/bblanchon/ArduinoJson
-// If you like this project, please add a star!
-
-#include <gtest/gtest.h>
-#include <ArduinoJson.h>
-
-class Issue67 : public testing::Test {
- public:
-  void whenInputIs(double value) { _variant = value; }
-
-  void outputMustBe(const char* expected) {
-    char buffer[1024];
-    _variant.printTo(buffer, sizeof(buffer));
-    ASSERT_STREQ(expected, buffer);
-  }
-
- private:
-  JsonVariant _variant;
-};
-
-TEST_F(Issue67, BigPositiveDouble) {
-  whenInputIs(1e100);
-  outputMustBe("1e+100");
-}
-
-TEST_F(Issue67, BigNegativeDouble) {
-  whenInputIs(-1e100);
-  outputMustBe("-1e+100");
-}
-
-TEST_F(Issue67, Zero) {
-  whenInputIs(0.0);
-  outputMustBe("0.00");
-}
-
-TEST_F(Issue67, SmallPositiveDouble) {
-  whenInputIs(111.111);
-  outputMustBe("111.11");
-}
-
-TEST_F(Issue67, SmallNegativeDouble) {
-  whenInputIs(-111.111);
-  outputMustBe("-111.11");
-}

test/JsonVariant_PrintTo_Tests.cpp

@@ -7,6 +7,7 @@
 
 #include <gtest/gtest.h>
 #include <ArduinoJson.h>
+#include <limits>
 
 class JsonVariant_PrintTo_Tests : public testing::Test {
  protected:
@@ -15,8 +16,8 @@ class JsonVariant_PrintTo_Tests : public testing::Test {
   void outputMustBe(const char *expected) {
     char buffer[256] = "";
     size_t n = variant.printTo(buffer, sizeof(buffer));
-    EXPECT_STREQ(expected, buffer);
-    EXPECT_EQ(strlen(expected), n);
+    ASSERT_STREQ(expected, buffer);
+    ASSERT_EQ(strlen(expected), n);
   }
 };
 
@@ -47,6 +48,46 @@ TEST_F(JsonVariant_PrintTo_Tests, DoubleFourDigits) {
   outputMustBe("3.1416");
 }
 
+TEST_F(JsonVariant_PrintTo_Tests, Infinity) {
+  variant = std::numeric_limits<double>::infinity();
+  outputMustBe("Infinity");
+}
+
+TEST_F(JsonVariant_PrintTo_Tests, MinusInfinity) {
+  variant = -std::numeric_limits<double>::infinity();
+  outputMustBe("-Infinity");
+}
+
+TEST_F(JsonVariant_PrintTo_Tests, SignalingNaN) {
+  variant = std::numeric_limits<double>::signaling_NaN();
+  outputMustBe("NaN");
+}
+
+TEST_F(JsonVariant_PrintTo_Tests, QuietNaN) {
+  variant = std::numeric_limits<double>::quiet_NaN();
+  outputMustBe("NaN");
+}
+
+TEST_F(JsonVariant_PrintTo_Tests, VeryBigPositiveDouble) {
+  variant = JsonVariant(3.14159265358979323846e42, 4);
+  outputMustBe("3.1416e42");
+}
+
+TEST_F(JsonVariant_PrintTo_Tests, VeryBigNegativeDouble) {
+  variant = JsonVariant(-3.14159265358979323846e42, 4);
+  outputMustBe("-3.1416e42");
+}
+
+TEST_F(JsonVariant_PrintTo_Tests, VerySmallPositiveDouble) {
+  variant = JsonVariant(3.14159265358979323846e-42, 4);
+  outputMustBe("3.1416e-42");
+}
+
+TEST_F(JsonVariant_PrintTo_Tests, VerySmallNegativeDouble) {
+  variant = JsonVariant(-3.14159265358979323846e-42, 4);
+  outputMustBe("-3.1416e-42");
+}
+
 TEST_F(JsonVariant_PrintTo_Tests, Integer) {
   variant = 42;
   outputMustBe("42");
@@ -62,11 +103,6 @@ TEST_F(JsonVariant_PrintTo_Tests, UnsignedLong) {
   outputMustBe("4294967295");
 }
 
-TEST_F(JsonVariant_PrintTo_Tests, Char) {
-  variant = '*';
-  outputMustBe("42");
-}
-
 TEST_F(JsonVariant_PrintTo_Tests, True) {
   variant = true;
   outputMustBe("true");