Add StringAdapter<T>

src/ArduinoJson/Strings/Adapters/ArduinoString.hpp

@@ -8,12 +8,20 @@
 
 #include <ArduinoJson/Strings/Adapters/RamString.hpp>
 #include <ArduinoJson/Strings/IsString.hpp>
+#include <ArduinoJson/Strings/StringAdapter.hpp>
 
 namespace ARDUINOJSON_NAMESPACE {
 
-inline SizedRamString adaptString(const ::String& s) {
+template <typename T>
-  return SizedRamString(s.c_str(), s.length());
+struct StringAdapter<
+    T, typename enable_if<is_same<T, ::String>::value ||
+                          is_same<T, ::StringSumHelper>::value>::type> {
+  typedef SizedRamString AdaptedString;
+
+  static AdaptedString adapt(const ::String& s) {
+    return AdaptedString(s.c_str(), s.length());
   }
+};
 
 template <>
 struct IsString< ::String> : true_type {};

src/ArduinoJson/Strings/Adapters/FlashString.hpp

@@ -70,13 +70,23 @@ class FlashString {
   size_t _size;
 };
 
-inline FlashString adaptString(const __FlashStringHelper* s) {
+template <>
-  return FlashString(s, s ? strlen_P(reinterpret_cast<const char*>(s)) : 0);
+struct StringAdapter<const __FlashStringHelper*, void> {
-}
+  typedef FlashString AdaptedString;
 
-inline FlashString adaptString(const __FlashStringHelper* s, size_t n) {
+  static AdaptedString adapt(const __FlashStringHelper* s) {
-  return FlashString(s, n);
+    return AdaptedString(s, s ? strlen_P(reinterpret_cast<const char*>(s)) : 0);
   }
+};
+
+template <>
+struct SizedStringAdapter<const __FlashStringHelper*, void> {
+  typedef FlashString AdaptedString;
+
+  static AdaptedString adapt(const __FlashStringHelper* s, size_t n) {
+    return AdaptedString(s, n);
+  }
+};
 
 template <>
 struct IsString<const __FlashStringHelper*> : true_type {};

src/ArduinoJson/Strings/Adapters/JsonString.hpp

@@ -24,9 +24,14 @@ class JsonStringAdapter : public SizedRamString {
   bool _linked;
 };
 
-inline JsonStringAdapter adaptString(const String& s) {
+template <>
-  return JsonStringAdapter(s);
+struct StringAdapter<String> {
+  typedef JsonStringAdapter AdaptedString;
+
+  static AdaptedString adapt(const String& s) {
+    return AdaptedString(s);
   }
+};
 
 template <>
 struct IsString<String> : true_type {};

src/ArduinoJson/Strings/Adapters/RamString.hpp

@@ -10,6 +10,7 @@
 #include <ArduinoJson/Polyfills/assert.hpp>
 #include <ArduinoJson/Strings/IsString.hpp>
 #include <ArduinoJson/Strings/StoragePolicy.hpp>
+#include <ArduinoJson/Strings/StringAdapter.hpp>
 
 namespace ARDUINOJSON_NAMESPACE {
 
@@ -60,23 +61,35 @@ class ZeroTerminatedRamString {
 template <>
 struct IsString<char*> : true_type {};
 
-inline ZeroTerminatedRamString adaptString(char* s) {
-  return ZeroTerminatedRamString(s);
-}
-
 template <>
 struct IsString<unsigned char*> : true_type {};
 
-inline ZeroTerminatedRamString adaptString(const unsigned char* s) {
+template <typename TChar>
-  return ZeroTerminatedRamString(reinterpret_cast<const char*>(s));
+struct StringAdapter<TChar*, typename enable_if<sizeof(TChar) == 1>::type> {
+  typedef ZeroTerminatedRamString AdaptedString;
+
+  static AdaptedString adapt(const TChar* p) {
+    return AdaptedString(reinterpret_cast<const char*>(p));
   }
+};
 
 template <>
 struct IsString<signed char*> : true_type {};
 
-inline ZeroTerminatedRamString adaptString(const signed char* s) {
+template <size_t N>
-  return ZeroTerminatedRamString(reinterpret_cast<const char*>(s));
+struct IsString<char[N]> : true_type {};
+
+template <size_t N>
+struct IsString<const char[N]> : true_type {};
+
+template <typename TChar, size_t N>
+struct StringAdapter<TChar[N], typename enable_if<sizeof(TChar) == 1>::type> {
+  typedef ZeroTerminatedRamString AdaptedString;
+
+  static AdaptedString adapt(const TChar* p) {
+    return AdaptedString(reinterpret_cast<const char*>(p));
   }
+};
 
 class StaticStringAdapter : public ZeroTerminatedRamString {
  public:
@@ -87,9 +100,14 @@ class StaticStringAdapter : public ZeroTerminatedRamString {
   }
 };
 
-inline StaticStringAdapter adaptString(const char* s) {
+template <>
-  return StaticStringAdapter(s);
+struct StringAdapter<const char*, void> {
+  typedef StaticStringAdapter AdaptedString;
+
+  static AdaptedString adapt(const char* p) {
+    return AdaptedString(p);
   }
+};
 
 class SizedRamString {
  public:
@@ -124,18 +142,14 @@ class SizedRamString {
   size_t _size;
 };
 
-inline SizedRamString adaptString(const char* s, size_t n) {
+template <typename TChar>
-  return SizedRamString(s, n);
+struct SizedStringAdapter<TChar*,
+                          typename enable_if<sizeof(TChar) == 1>::type> {
+  typedef SizedRamString AdaptedString;
+
+  static AdaptedString adapt(const TChar* p, size_t n) {
+    return AdaptedString(reinterpret_cast<const char*>(p), n);
   }
+};
 
-template <size_t N>
-struct IsString<char[N]> : true_type {};
-
-template <size_t N>
-struct IsString<const char[N]> : true_type {};
-
-template <size_t N>
-inline SizedRamString adaptString(char s[N]) {
-  return SizedRamString(s, strlen(s));
-}
 }  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Strings/Adapters/StdString.hpp

@@ -11,10 +11,14 @@
 namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TCharTraits, typename TAllocator>
-inline SizedRamString adaptString(
+struct StringAdapter<std::basic_string<char, TCharTraits, TAllocator>, void> {
+  typedef SizedRamString AdaptedString;
+
+  static AdaptedString adapt(
       const std::basic_string<char, TCharTraits, TAllocator>& s) {
-  return SizedRamString(s.c_str(), s.size());
+    return AdaptedString(s.c_str(), s.size());
   }
+};
 
 template <typename TCharTraits, typename TAllocator>
 struct IsString<std::basic_string<char, TCharTraits, TAllocator> > : true_type {

src/ArduinoJson/Strings/Adapters/StringView.hpp

@@ -10,9 +10,14 @@
 
 namespace ARDUINOJSON_NAMESPACE {
 
-inline SizedRamString adaptString(const std::string_view& s) {
+template <>
-  return SizedRamString(s.data(), s.size());
+struct StringAdapter<std::string_view, void> {
+  typedef SizedRamString AdaptedString;
+
+  static AdaptedString adapt(const std::string_view& s) {
+    return AdaptedString(s.data(), s.size());
   }
+};
 
 template <>
 struct IsString<std::string_view> : true_type {};

src/ArduinoJson/Strings/StringAdapter.hpp

@@ -0,0 +1,31 @@
+// ArduinoJson - https://arduinojson.org
+// Copyright © 2014-2022, Benoit BLANCHON
+// MIT License
+
+#pragma once
+
+namespace ARDUINOJSON_NAMESPACE {
+
+template <typename TString, typename Enable = void>
+struct StringAdapter;
+
+template <typename TString, typename Enable = void>
+struct SizedStringAdapter;
+
+template <typename TString>
+typename StringAdapter<TString>::AdaptedString adaptString(const TString& s) {
+  return StringAdapter<TString>::adapt(s);
+}
+
+template <typename TChar>
+typename StringAdapter<TChar*>::AdaptedString adaptString(TChar* p) {
+  return StringAdapter<TChar*>::adapt(p);
+}
+
+template <typename TChar>
+typename SizedStringAdapter<TChar*>::AdaptedString adaptString(TChar* p,
+                                                               size_t n) {
+  return SizedStringAdapter<TChar*>::adapt(p, n);
+}
+
+}  // namespace ARDUINOJSON_NAMESPACE