Reduced memory consumption by not duplicating spaces and comments

CHANGELOG.md

@@ -5,6 +5,7 @@ HEAD
 ----
 
 * Added operator `==` to compare `JsonVariant` and strings (issue #402)
+* Reduced memory consumption by not duplicating spaces and comments
 
 v5.7.3
 ------

include/ArduinoJson/Data/BlockJsonBuffer.hpp

@@ -1,115 +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!
-
-#pragma once
-
-#include "../JsonBuffer.hpp"
-
-#include <stdlib.h>
-
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic push
-#endif
-#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-#endif
-
-namespace ArduinoJson {
-namespace Internals {
-class DefaultAllocator {
- public:
-  void* allocate(size_t size) {
-    return malloc(size);
-  }
-  void deallocate(void* pointer) {
-    free(pointer);
-  }
-};
-
-template <typename TAllocator>
-class BlockJsonBuffer : public JsonBuffer {
-  struct Block;
-  struct EmptyBlock {
-    Block* next;
-    size_t capacity;
-    size_t size;
-  };
-  struct Block : EmptyBlock {
-    uint8_t data[1];
-  };
-
- public:
-  BlockJsonBuffer(size_t initialSize = 256)
-      : _head(NULL), _nextBlockSize(initialSize) {}
-
-  ~BlockJsonBuffer() {
-    Block* currentBlock = _head;
-
-    while (currentBlock != NULL) {
-      Block* nextBlock = currentBlock->next;
-      _allocator.deallocate(currentBlock);
-      currentBlock = nextBlock;
-    }
-  }
-
-  size_t size() const {
-    size_t total = 0;
-    for (const Block* b = _head; b; b = b->next) total += b->size;
-    return total;
-  }
-
-  virtual void* alloc(size_t bytes) {
-    return canAllocInHead(bytes) ? allocInHead(bytes) : allocInNewBlock(bytes);
-  }
-
- private:
-  bool canAllocInHead(size_t bytes) const {
-    return _head != NULL && _head->size + bytes <= _head->capacity;
-  }
-
-  void* allocInHead(size_t bytes) {
-    void* p = _head->data + _head->size;
-    _head->size += round_size_up(bytes);
-    return p;
-  }
-
-  void* allocInNewBlock(size_t bytes) {
-    size_t capacity = _nextBlockSize;
-    if (bytes > capacity) capacity = bytes;
-    if (!addNewBlock(capacity)) return NULL;
-    _nextBlockSize *= 2;
-    return allocInHead(bytes);
-  }
-
-  bool addNewBlock(size_t capacity) {
-    size_t bytes = sizeof(EmptyBlock) + capacity;
-    Block* block = static_cast<Block*>(_allocator.allocate(bytes));
-    if (block == NULL) return false;
-    block->capacity = capacity;
-    block->size = 0;
-    block->next = _head;
-    _head = block;
-    return true;
-  }
-
-  TAllocator _allocator;
-  Block* _head;
-  size_t _nextBlockSize;
-};
-}
-}
-
-#if defined(__clang__)
-#pragma clang diagnostic pop
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic pop
-#endif
-#endif

include/ArduinoJson/Data/StringFuncs.hpp

@@ -30,6 +30,17 @@ template <typename TString>
 struct StringFuncs<TString&> : StringFuncs<TString> {};
 
 struct CharPtrFuncs {
+  class Iterator {
+    const char* _ptr;
+
+   public:
+    Iterator(const char* ptr) : _ptr(ptr ? ptr : "") {}
+
+    char next() {
+      return *_ptr++;
+    }
+  };
+
   static bool equals(const char* str, const char* expected) {
     return strcmp(str, expected) == 0;
   }
@@ -71,6 +82,10 @@ struct StdStringFuncs {
     return static_cast<char*>(dup);
   }
 
+  struct Iterator : CharPtrFuncs::Iterator {
+    Iterator(const TString& str) : CharPtrFuncs::Iterator(str.c_str()) {}
+  };
+
   static bool equals(const TString& str, const char* expected) {
     return str == expected;
   }
@@ -99,6 +114,18 @@ struct StringFuncs<std::string> : StdStringFuncs<std::string> {};
 #if ARDUINOJSON_ENABLE_PROGMEM
 template <>
 struct StringFuncs<const __FlashStringHelper*> {
+  class Iterator {
+    const char* _ptr;
+
+   public:
+    Iterator(const __FlashStringHelper* ptr)
+        : _ptr(reinterpret_cast<const char*>(ptr)) {}
+
+    char next() {
+      return pgm_read_byte_near(_ptr++);
+    }
+  };
+
   static bool equals(const __FlashStringHelper* str, const char* expected) {
     return strcmp_P(expected, (PGM_P)str) == 0;
   }

include/ArduinoJson/Deserialization/Comments.hpp

@@ -12,51 +12,51 @@ namespace Internals {
 template <typename TInput>
 void skipSpacesAndComments(TInput& input) {
   for (;;) {
-    switch (input.peek()) {
+    switch (input.current()) {
       // spaces
       case ' ':
       case '\t':
       case '\r':
       case '\n':
-        input.skip();
+        input.move();
         continue;
 
       // comments
       case '/':
-        switch (input.peekNext()) {
+        switch (input.next()) {
           // C-style block comment
           case '*':
-            input.skip();  // skip '/'
+            input.move();  // skip '/'
-            input.skip();  // skip '*'
+            input.move();  // skip '*'
             for (;;) {
-              switch (input.peek()) {
+              switch (input.current()) {
                 case '\0':
                   return;
                 case '*':
-                  input.skip();  // skip '*'
+                  input.move();  // skip '*'
-                  if (input.peek() == '/') {
+                  if (input.current() == '/') {
-                    input.skip();  // skip '/'
+                    input.move();  // skip '/'
                     return;
                   }
                   break;
                 default:
-                  input.skip();
+                  input.move();
               }
             }
             break;
 
           // C++-style line comment
           case '/':
-            input.skip();  // skip '/'
+            input.move();  // skip '/'
             for (;;) {
-              switch (input.peek()) {
+              switch (input.current()) {
                 case '\0':
                   return;
                 case '\n':
-                  input.skip();
+                  input.move();
                   return;
                 default:
-                  input.skip();
+                  input.move();
               }
             }
             return;

include/ArduinoJson/Deserialization/JsonParser.hpp

@@ -18,12 +18,14 @@ namespace Internals {
 // Parse JSON string to create JsonArrays and JsonObjects
 // This internal class is not indended to be used directly.
 // Instead, use JsonBuffer.parseArray() or .parseObject()
+template <typename TReader, typename TWriter>
 class JsonParser {
  public:
-  JsonParser(JsonBuffer *buffer, char *json, uint8_t nestingLimit)
+  JsonParser(JsonBuffer *buffer, TReader reader, TWriter writer,
+             uint8_t nestingLimit)
       : _buffer(buffer),
-        _reader(json),
+        _reader(reader),
-        _writer(json),
+        _writer(writer),
         _nestingLimit(nestingLimit) {}
 
   JsonArray &parseArray();
@@ -36,7 +38,9 @@ class JsonParser {
   }
 
  private:
-  static bool eat(StringReader &, char charToSkip);
+  JsonParser &operator=(const JsonParser &);  // non-copiable
+
+  static bool eat(TReader &, char charToSkip);
   FORCE_INLINE bool eat(char charToSkip) {
     return eat(_reader, charToSkip);
   }
@@ -63,9 +67,42 @@ class JsonParser {
   }
 
   JsonBuffer *_buffer;
-  StringReader _reader;
+  TReader _reader;
-  StringWriter _writer;
+  TWriter _writer;
   uint8_t _nestingLimit;
 };
+
+template <typename TJsonBuffer, typename TString>
+struct JsonParserBuilder {
+  typedef typename Internals::StringFuncs<TString>::Iterator InputIterator;
+  typedef JsonParser<StringReader<InputIterator>, TJsonBuffer &> TParser;
+
+  static TParser makeParser(TJsonBuffer *buffer, const TString &json,
+                            uint8_t nestingLimit) {
+    return TParser(buffer, InputIterator(json), *buffer, nestingLimit);
+  }
+};
+
+template <typename TJsonBuffer>
+struct JsonParserBuilder<TJsonBuffer, char *> {
+  typedef typename Internals::StringFuncs<char *>::Iterator InputIterator;
+  typedef JsonParser<StringReader<InputIterator>, StringWriter> TParser;
+
+  static TParser makeParser(TJsonBuffer *buffer, char *json,
+                            uint8_t nestingLimit) {
+    return TParser(buffer, InputIterator(json), json, nestingLimit);
+  }
+};
+
+template <typename TJsonBuffer, typename TChar, size_t N>
+struct JsonParserBuilder<TJsonBuffer, TChar[N]>
+    : JsonParserBuilder<TJsonBuffer, TChar *> {};
+
+template <typename TJsonBuffer, typename TString>
+inline typename JsonParserBuilder<TJsonBuffer, TString>::TParser makeParser(
+    TJsonBuffer *buffer, TString &json, uint8_t nestingLimit) {
+  return JsonParserBuilder<TJsonBuffer, TString>::makeParser(buffer, json,
+                                                             nestingLimit);
+}
 }
 }

include/ArduinoJson/Deserialization/JsonParserImpl.hpp

@@ -10,16 +10,19 @@
 #include "Comments.hpp"
 #include "JsonParser.hpp"
 
-inline bool ArduinoJson::Internals::JsonParser::eat(StringReader &reader,
+template <typename TReader, typename TWriter>
-                                                    char charToSkip) {
+inline bool ArduinoJson::Internals::JsonParser<TReader, TWriter>::eat(
+    TReader &reader, char charToSkip) {
   skipSpacesAndComments(reader);
-  if (reader.peek() != charToSkip) return false;
+  if (reader.current() != charToSkip) return false;
-  reader.skip();
+  reader.move();
   skipSpacesAndComments(reader);
   return true;
 }
 
-inline bool ArduinoJson::Internals::JsonParser::parseAnythingTo(
+template <typename TReader, typename TWriter>
+inline bool
+ArduinoJson::Internals::JsonParser<TReader, TWriter>::parseAnythingTo(
     JsonVariant *destination) {
   if (_nestingLimit == 0) return false;
   _nestingLimit--;
@@ -28,11 +31,13 @@ inline bool ArduinoJson::Internals::JsonParser::parseAnythingTo(
   return success;
 }
 
-inline bool ArduinoJson::Internals::JsonParser::parseAnythingToUnsafe(
+template <typename TReader, typename TWriter>
+inline bool
+ArduinoJson::Internals::JsonParser<TReader, TWriter>::parseAnythingToUnsafe(
     JsonVariant *destination) {
   skipSpacesAndComments(_reader);
 
-  switch (_reader.peek()) {
+  switch (_reader.current()) {
     case '[':
       return parseArrayTo(destination);
 
@@ -44,8 +49,9 @@ inline bool ArduinoJson::Internals::JsonParser::parseAnythingToUnsafe(
   }
 }
 
+template <typename TReader, typename TWriter>
 inline ArduinoJson::JsonArray &
-ArduinoJson::Internals::JsonParser::parseArray() {
+ArduinoJson::Internals::JsonParser<TReader, TWriter>::parseArray() {
   // Create an empty array
   JsonArray &array = _buffer->createArray();
 
@@ -76,7 +82,8 @@ ERROR_NO_MEMORY:
   return JsonArray::invalid();
 }
 
-inline bool ArduinoJson::Internals::JsonParser::parseArrayTo(
+template <typename TReader, typename TWriter>
+inline bool ArduinoJson::Internals::JsonParser<TReader, TWriter>::parseArrayTo(
     JsonVariant *destination) {
   JsonArray &array = parseArray();
   if (!array.success()) return false;
@@ -85,8 +92,9 @@ inline bool ArduinoJson::Internals::JsonParser::parseArrayTo(
   return true;
 }
 
+template <typename TReader, typename TWriter>
 inline ArduinoJson::JsonObject &
-ArduinoJson::Internals::JsonParser::parseObject() {
+ArduinoJson::Internals::JsonParser<TReader, TWriter>::parseObject() {
   // Create an empty object
   JsonObject &object = _buffer->createObject();
 
@@ -124,7 +132,8 @@ ERROR_NO_MEMORY:
   return JsonObject::invalid();
 }
 
-inline bool ArduinoJson::Internals::JsonParser::parseObjectTo(
+template <typename TReader, typename TWriter>
+inline bool ArduinoJson::Internals::JsonParser<TReader, TWriter>::parseObjectTo(
     JsonVariant *destination) {
   JsonObject &object = parseObject();
   if (!object.success()) return false;
@@ -133,46 +142,49 @@ inline bool ArduinoJson::Internals::JsonParser::parseObjectTo(
   return true;
 }
 
-inline const char *ArduinoJson::Internals::JsonParser::parseString() {
+template <typename TReader, typename TWriter>
-  const char *str = _writer.startString();
+inline const char *
+ArduinoJson::Internals::JsonParser<TReader, TWriter>::parseString() {
+  typename TypeTraits::RemoveReference<TWriter>::type::String str =
+      _writer.startString();
 
-  char c = _reader.peek();
+  char c = _reader.current();
 
   if (isQuote(c)) {  // quotes
-    _reader.skip();
+    _reader.move();
     char stopChar = c;
     for (;;) {
-      c = _reader.peek();
+      c = _reader.current();
       if (c == '\0') break;
-      _reader.skip();
+      _reader.move();
 
       if (c == stopChar) break;
 
       if (c == '\\') {
         // replace char
-        c = Encoding::unescapeChar(_reader.peek());
+        c = Encoding::unescapeChar(_reader.current());
         if (c == '\0') break;
-        _reader.skip();
+        _reader.move();
       }
 
-      _writer.append(c);
+      str.append(c);
     }
   } else {  // no quotes
     for (;;) {
       if (!isLetterOrNumber(c)) break;
-      _reader.skip();
+      _reader.move();
-      _writer.append(c);
+      str.append(c);
-      c = _reader.peek();
+      c = _reader.current();
     }
   }
 
-  _writer.stopString();
+  return str.c_str();
-  return str;
 }
 
-inline bool ArduinoJson::Internals::JsonParser::parseStringTo(
+template <typename TReader, typename TWriter>
+inline bool ArduinoJson::Internals::JsonParser<TReader, TWriter>::parseStringTo(
     JsonVariant *destination) {
-  bool hasQuotes = isQuote(_reader.peek());
+  bool hasQuotes = isQuote(_reader.current());
   const char *value = parseString();
   if (value == NULL) return false;
   if (hasQuotes) {

include/ArduinoJson/Deserialization/StringReader.hpp

@@ -13,24 +13,29 @@ namespace Internals {
 // Parse JSON string to create JsonArrays and JsonObjects
 // This internal class is not indended to be used directly.
 // Instead, use JsonBuffer.parseArray() or .parseObject()
+template <typename TIterator>
 class StringReader {
+  TIterator _input;
+  char _current, _next;
+
  public:
-  StringReader(const char *input) : _ptr(input ? input : "") {}
+  StringReader(const TIterator& input) : _input(input) {
-
+    _current = _input.next();
-  void skip() {
+    _next = _input.next();
-    _ptr++;
   }
 
-  char peek() const {
+  void move() {
-    return _ptr[0];
+    _current = _next;
+    _next = _input.next();
   }
 
-  char peekNext() const {
+  char current() const {
-    return _ptr[1];
+    return _current;
   }
 
- private:
+  char next() const {
-  const char *_ptr;
+    return _next;
+  }
 };
 }
 }

include/ArduinoJson/Deserialization/StringWriter.hpp

@@ -10,27 +10,34 @@
 namespace ArduinoJson {
 namespace Internals {
 
-// Parse JSON string to create JsonArrays and JsonObjects
-// This internal class is not indended to be used directly.
-// Instead, use JsonBuffer.parseArray() or .parseObject()
 class StringWriter {
  public:
-  StringWriter(char *buffer) : _ptr(buffer) {}
+  class String {
-
+   public:
-  const char *startString() {
+    String(char** ptr) : _writePtr(ptr), _startPtr(*ptr) {}
-    return _ptr;
-  }
-
-  void stopString() {
-    *_ptr++ = 0;
-  }
 
     void append(char c) {
-    *_ptr++ = c;
+      *(*_writePtr)++ = c;
+    }
+
+    const char* c_str() const {
+      *(*_writePtr)++ = 0;
+      return _startPtr;
     }
 
    private:
-  char *_ptr;
+    char** _writePtr;
+    char* _startPtr;
+  };
+
+  StringWriter(char* buffer) : _ptr(buffer) {}
+
+  String startString() {
+    return String(&_ptr);
+  }
+
+ private:
+  char* _ptr;
 };
 }
 }

include/ArduinoJson/DynamicJsonBuffer.hpp

@@ -7,12 +7,153 @@
 
 #pragma once
 
-#include "Data/BlockJsonBuffer.hpp"
+#include "JsonBufferBase.hpp"
+
+#include <stdlib.h>
+
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
+#elif defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic push
+#endif
+#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
+#endif
 
 namespace ArduinoJson {
+class DefaultAllocator {
+ public:
+  void* allocate(size_t size) {
+    return malloc(size);
+  }
+  void deallocate(void* pointer) {
+    free(pointer);
+  }
+};
+
+template <typename TAllocator>
+class DynamicJsonBufferBase
+    : public JsonBufferBase<DynamicJsonBufferBase<TAllocator> > {
+  struct Block;
+  struct EmptyBlock {
+    Block* next;
+    size_t capacity;
+    size_t size;
+  };
+  struct Block : EmptyBlock {
+    uint8_t data[1];
+  };
+
+ public:
+  DynamicJsonBufferBase(size_t initialSize = 256)
+      : _head(NULL), _nextBlockCapacity(initialSize) {}
+
+  ~DynamicJsonBufferBase() {
+    Block* currentBlock = _head;
+
+    while (currentBlock != NULL) {
+      Block* nextBlock = currentBlock->next;
+      _allocator.deallocate(currentBlock);
+      currentBlock = nextBlock;
+    }
+  }
+
+  size_t size() const {
+    size_t total = 0;
+    for (const Block* b = _head; b; b = b->next) total += b->size;
+    return total;
+  }
+
+  virtual void* alloc(size_t bytes) {
+    alignNextAlloc();
+    return canAllocInHead(bytes) ? allocInHead(bytes) : allocInNewBlock(bytes);
+  }
+
+  class String {
+   public:
+    String(DynamicJsonBufferBase* parent)
+        : _parent(parent), _start(NULL), _length(0) {}
+
+    void append(char c) {
+      if (_parent->canAllocInHead(1)) {
+        char* end = static_cast<char*>(_parent->allocInHead(1));
+        *end = c;
+        if (_length == 0) _start = end;
+      } else {
+        char* newStart =
+            static_cast<char*>(_parent->allocInNewBlock(_length + 1));
+        if (_start && newStart) memcpy(newStart, _start, _length);
+        newStart[_length] = c;
+        _start = newStart;
+      }
+      _length++;
+    }
+
+    const char* c_str() {
+      append(0);
+      return _start;
+    }
+
+   private:
+    DynamicJsonBufferBase* _parent;
+    char* _start;
+    int _length;
+  };
+
+  String startString() {
+    return String(this);
+  }
+
+ private:
+  void alignNextAlloc() {
+    if (_head) _head->size = this->round_size_up(_head->size);
+  }
+
+  bool canAllocInHead(size_t bytes) const {
+    return _head != NULL && _head->size + bytes <= _head->capacity;
+  }
+
+  void* allocInHead(size_t bytes) {
+    void* p = _head->data + _head->size;
+    _head->size += bytes;
+    return p;
+  }
+
+  void* allocInNewBlock(size_t bytes) {
+    size_t capacity = _nextBlockCapacity;
+    if (bytes > capacity) capacity = bytes;
+    if (!addNewBlock(capacity)) return NULL;
+    _nextBlockCapacity *= 2;
+    return allocInHead(bytes);
+  }
+
+  bool addNewBlock(size_t capacity) {
+    size_t bytes = sizeof(EmptyBlock) + capacity;
+    Block* block = static_cast<Block*>(_allocator.allocate(bytes));
+    if (block == NULL) return false;
+    block->capacity = capacity;
+    block->size = 0;
+    block->next = _head;
+    _head = block;
+    return true;
+  }
+
+  TAllocator _allocator;
+  Block* _head;
+  size_t _nextBlockCapacity;
+};
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#elif defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic pop
+#endif
+#endif
+
 // Implements a JsonBuffer with dynamic memory allocation.
 // You are strongly encouraged to consider using StaticJsonBuffer which is much
 // more suitable for embedded systems.
-typedef Internals::BlockJsonBuffer<Internals::DefaultAllocator>
+typedef DynamicJsonBufferBase<DefaultAllocator> DynamicJsonBuffer;
-    DynamicJsonBuffer;
 }

include/ArduinoJson/JsonBuffer.hpp

@@ -51,58 +51,6 @@ class JsonBuffer {
   // allocation fails.
   JsonObject &createObject();
 
-  // Allocates and populate a JsonArray from a JSON string.
-  //
-  // The First argument is a pointer to the JSON string, the memory must be
-  // writable
-  // because the parser will insert null-terminators and replace escaped chars.
-  //
-  // The second argument set the nesting limit
-  //
-  // Returns a reference to the new JsonObject or JsonObject::invalid() if the
-  // allocation fails.
-  JsonArray &parseArray(
-      char *json, uint8_t nestingLimit = ARDUINOJSON_DEFAULT_NESTING_LIMIT);
-
-  // With this overload, the JsonBuffer will make a copy of the string
-  template <typename TString>
-  JsonArray &parseArray(const TString &json,
-                        uint8_t nesting = ARDUINOJSON_DEFAULT_NESTING_LIMIT) {
-    return parseArray(strdup(json), nesting);
-  }
-
-  // Allocates and populate a JsonObject from a JSON string.
-  //
-  // The First argument is a pointer to the JSON string, the memory must be
-  // writable
-  // because the parser will insert null-terminators and replace escaped chars.
-  //
-  // The second argument set the nesting limit
-  //
-  // Returns a reference to the new JsonObject or JsonObject::invalid() if the
-  // allocation fails.
-  JsonObject &parseObject(
-      char *json, uint8_t nestingLimit = ARDUINOJSON_DEFAULT_NESTING_LIMIT);
-
-  // With this overload, the JsonBuffer will make a copy of the string
-  template <typename TString>
-  JsonObject &parseObject(const TString &json,
-                          uint8_t nesting = ARDUINOJSON_DEFAULT_NESTING_LIMIT) {
-    return parseObject(strdup(json), nesting);
-  }
-
-  // Generalized version of parseArray() and parseObject(), also works for
-  // integral types.
-  JsonVariant parse(char *json,
-                    uint8_t nestingLimit = ARDUINOJSON_DEFAULT_NESTING_LIMIT);
-
-  // With this overload, the JsonBuffer will make a copy of the string
-  template <typename TString>
-  JsonVariant parse(const TString &json,
-                    uint8_t nesting = ARDUINOJSON_DEFAULT_NESTING_LIMIT) {
-    return parse(strdup(json), nesting);
-  }
-
   // Duplicate a string
   template <typename TString>
   char *strdup(const TString &src) {
@@ -114,7 +62,7 @@ class JsonBuffer {
   virtual void *alloc(size_t size) = 0;
 
  protected:
-  // Preserve aligment if nessary
+  // Preserve aligment if necessary
   static FORCE_INLINE size_t round_size_up(size_t bytes) {
 #if ARDUINOJSON_ENABLE_ALIGNMENT
     const size_t x = sizeof(void *) - 1;

include/ArduinoJson/JsonBufferBase.hpp

@@ -0,0 +1,97 @@
+// 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 "Deserialization/JsonParser.hpp"
+
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
+#elif defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic push
+#endif
+#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
+#endif
+
+namespace ArduinoJson {
+template <typename TDerived>
+class JsonBufferBase : public JsonBuffer {
+ public:
+  // Allocates and populate a JsonArray from a JSON string.
+  //
+  // The First argument is a pointer to the JSON string, the memory must be
+  // writable
+  // because the parser will insert null-terminators and replace escaped chars.
+  //
+  // The second argument set the nesting limit
+  //
+  // Returns a reference to the new JsonObject or JsonObject::invalid() if the
+  // allocation fails.
+  // With this overload, the JsonBuffer will make a copy of the string
+  template <typename TString>
+  JsonArray &parseArray(
+      const TString &json,
+      uint8_t nestingLimit = ARDUINOJSON_DEFAULT_NESTING_LIMIT) {
+    return Internals::makeParser(that(), json, nestingLimit).parseArray();
+  }
+  template <typename TString>
+  JsonArray &parseArray(
+      TString &json, uint8_t nestingLimit = ARDUINOJSON_DEFAULT_NESTING_LIMIT) {
+    return Internals::makeParser(that(), json, nestingLimit).parseArray();
+  }
+
+  // Allocates and populate a JsonObject from a JSON string.
+  //
+  // The First argument is a pointer to the JSON string, the memory must be
+  // writable
+  // because the parser will insert null-terminators and replace escaped chars.
+  //
+  // The second argument set the nesting limit
+  //
+  // Returns a reference to the new JsonObject or JsonObject::invalid() if the
+  // allocation fails.
+  template <typename TString>
+  JsonObject &parseObject(
+      const TString &json,
+      uint8_t nestingLimit = ARDUINOJSON_DEFAULT_NESTING_LIMIT) {
+    return Internals::makeParser(that(), json, nestingLimit).parseObject();
+  }
+  template <typename TString>
+  JsonObject &parseObject(
+      TString &json, uint8_t nestingLimit = ARDUINOJSON_DEFAULT_NESTING_LIMIT) {
+    return Internals::makeParser(that(), json, nestingLimit).parseObject();
+  }
+
+  // Generalized version of parseArray() and parseObject(), also works for
+  // integral types.
+  template <typename TString>
+  JsonVariant parse(const TString &json,
+                    uint8_t nestingLimit = ARDUINOJSON_DEFAULT_NESTING_LIMIT) {
+    return Internals::makeParser(that(), json, nestingLimit).parseVariant();
+  }
+  template <typename TString>
+  JsonVariant parse(TString &json,
+                    uint8_t nestingLimit = ARDUINOJSON_DEFAULT_NESTING_LIMIT) {
+    return Internals::makeParser(that(), json, nestingLimit).parseVariant();
+  }
+
+ private:
+  TDerived *that() {
+    return static_cast<TDerived *>(this);
+  }
+};
+}
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#elif defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic pop
+#endif
+#endif

include/ArduinoJson/JsonBufferImpl.hpp

@@ -18,21 +18,3 @@ inline ArduinoJson::JsonObject &ArduinoJson::JsonBuffer::createObject() {
   JsonObject *ptr = new (this) JsonObject(this);
   return ptr ? *ptr : JsonObject::invalid();
 }
-
-inline ArduinoJson::JsonArray &ArduinoJson::JsonBuffer::parseArray(
-    char *json, uint8_t nestingLimit) {
-  Internals::JsonParser parser(this, json, nestingLimit);
-  return parser.parseArray();
-}
-
-inline ArduinoJson::JsonObject &ArduinoJson::JsonBuffer::parseObject(
-    char *json, uint8_t nestingLimit) {
-  Internals::JsonParser parser(this, json, nestingLimit);
-  return parser.parseObject();
-}
-
-inline ArduinoJson::JsonVariant ArduinoJson::JsonBuffer::parse(
-    char *json, uint8_t nestingLimit) {
-  Internals::JsonParser parser(this, json, nestingLimit);
-  return parser.parseVariant();
-}

include/ArduinoJson/JsonVariantComparisons.hpp

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include "Internals/StringFuncs.hpp"
+#include "Data/StringFuncs.hpp"
 #include "JsonVariantBase.hpp"
 #include "TypeTraits/EnableIf.hpp"
 

include/ArduinoJson/StaticJsonBuffer.hpp

@@ -7,7 +7,7 @@
 
 #pragma once
 
-#include "JsonBuffer.hpp"
+#include "JsonBufferBase.hpp"
 
 #if defined(__clang__)
 #pragma clang diagnostic push
@@ -21,32 +21,87 @@
 
 namespace ArduinoJson {
 
-// Implements a JsonBuffer with fixed memory allocation.
+class StaticJsonBufferBase : public JsonBufferBase<StaticJsonBufferBase> {
-// The template paramenter CAPACITY specifies the capacity of the buffer in
-// bytes.
-template <size_t CAPACITY>
-class StaticJsonBuffer : public JsonBuffer {
  public:
-  explicit StaticJsonBuffer() : _size(0) {}
+  class String {
+   public:
+    String(StaticJsonBufferBase* parent) : _parent(parent) {
+      _start = parent->_buffer + parent->_size;
+    }
+
+    void append(char c) {
+      if (_parent->canAlloc(1)) {
+        char* last = static_cast<char*>(_parent->doAlloc(1));
+        *last = c;
+      }
+    }
+
+    const char* c_str() const {
+      if (_parent->canAlloc(1)) {
+        char* last = static_cast<char*>(_parent->doAlloc(1));
+        *last = '\0';
+        return _start;
+      } else {
+        return NULL;
+      }
+    }
+
+   private:
+    StaticJsonBufferBase* _parent;
+    char* _start;
+  };
+
+  StaticJsonBufferBase(char* buffer, size_t capa)
+      : _buffer(buffer), _capacity(capa), _size(0) {}
 
   size_t capacity() const {
-    return CAPACITY;
+    return _capacity;
   }
   size_t size() const {
     return _size;
   }
 
   virtual void* alloc(size_t bytes) {
-    if (_size + bytes > CAPACITY) return NULL;
+    alignNextAlloc();
-    void* p = &_buffer[_size];
+    if (!canAlloc(bytes)) return NULL;
-    _size += round_size_up(bytes);
+    return doAlloc(bytes);
-    return p;
+  }
+
+  String startString() {
+    return String(this);
   }
 
  private:
-  uint8_t _buffer[CAPACITY];
+  void alignNextAlloc() {
+    _size = round_size_up(_size);
+  }
+
+  bool canAlloc(size_t bytes) const {
+    return _size + bytes <= _capacity;
+  }
+
+  void* doAlloc(size_t bytes) {
+    void* p = &_buffer[_size];
+    _size += bytes;
+    return p;
+  }
+
+  char* _buffer;
+  size_t _capacity;
   size_t _size;
 };
+
+// Implements a JsonBuffer with fixed memory allocation.
+// The template paramenter CAPACITY specifies the capacity of the buffer in
+// bytes.
+template <size_t CAPACITY>
+class StaticJsonBuffer : public StaticJsonBufferBase {
+ public:
+  explicit StaticJsonBuffer() : StaticJsonBufferBase(_buffer, CAPACITY) {}
+
+ private:
+  char _buffer[CAPACITY];
+};
 }
 
 #if defined(__clang__)

test/DynamicJsonBuffer_Basic_Tests.cpp

@@ -30,13 +30,19 @@ TEST_F(DynamicJsonBuffer_Basic_Tests, ReturnDifferentPointer) {
   ASSERT_NE(p1, p2);
 }
 
-TEST_F(DynamicJsonBuffer_Basic_Tests, Alignment) {
+static bool isAligned(void* ptr) {
-  size_t mask = sizeof(void*) - 1;
+  const size_t mask = sizeof(void*) - 1;
+  size_t addr = reinterpret_cast<size_t>(ptr);
+  return (addr & mask) == 0;
+}
 
-  for (size_t size = 1; size <= sizeof(void*); size++) {
+TEST_F(DynamicJsonBuffer_Basic_Tests, Alignment) {
-    size_t addr = reinterpret_cast<size_t>(buffer.alloc(1));
+  // make room for tow but not three
-    ASSERT_EQ(0, addr & mask);
+  buffer = DynamicJsonBuffer(2 * sizeof(void*) + 1);
-  }
+
+  ASSERT_TRUE(isAligned(buffer.alloc(1)));  // this on is aligned by design
+  ASSERT_TRUE(isAligned(buffer.alloc(1)));  // this one fits in the first block
+  ASSERT_TRUE(isAligned(buffer.alloc(1)));  // this one requires a new block
 }
 
 TEST_F(DynamicJsonBuffer_Basic_Tests, strdup) {

test/DynamicJsonBuffer_NoMemory_Tests.cpp

@@ -5,18 +5,20 @@
 // https://github.com/bblanchon/ArduinoJson
 // If you like this project, please add a star!
 
-#include <gtest/gtest.h>
 #include <ArduinoJson.h>
+#include <gtest/gtest.h>
 
 class NoMemoryAllocator {
  public:
-  void* allocate(size_t) { return NULL; }
+  void* allocate(size_t) {
+    return NULL;
+  }
   void deallocate(void*) {}
 };
 
 class DynamicJsonBuffer_NoMemory_Tests : public ::testing::Test {
  protected:
-  Internals::BlockJsonBuffer<NoMemoryAllocator> _jsonBuffer;
+  DynamicJsonBufferBase<NoMemoryAllocator> _jsonBuffer;
 };
 
 TEST_F(DynamicJsonBuffer_NoMemory_Tests, FixCodeCoverage) {

test/DynamicJsonBuffer_String_Tests.cpp

@@ -0,0 +1,48 @@
+// 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 <ArduinoJson.h>
+#include <gtest/gtest.h>
+
+TEST(DynamicJsonBuffer_String_Tests, WorksWhenBufferIsBigEnough) {
+  DynamicJsonBuffer jsonBuffer(6);
+
+  DynamicJsonBuffer::String str = jsonBuffer.startString();
+  str.append('h');
+  str.append('e');
+  str.append('l');
+  str.append('l');
+  str.append('o');
+
+  ASSERT_STREQ("hello", str.c_str());
+}
+
+TEST(DynamicJsonBuffer_String_Tests, GrowsWhenBufferIsTooSmall) {
+  DynamicJsonBuffer jsonBuffer(5);
+
+  DynamicJsonBuffer::String str = jsonBuffer.startString();
+  str.append('h');
+  str.append('e');
+  str.append('l');
+  str.append('l');
+  str.append('o');
+
+  ASSERT_STREQ("hello", str.c_str());
+}
+
+TEST(DynamicJsonBuffer_String_Tests, SizeIncreases) {
+  DynamicJsonBuffer jsonBuffer(5);
+
+  DynamicJsonBuffer::String str = jsonBuffer.startString();
+  ASSERT_EQ(0, jsonBuffer.size());
+
+  str.append('h');
+  ASSERT_EQ(1, jsonBuffer.size());
+
+  str.c_str();
+  ASSERT_EQ(2, jsonBuffer.size());
+}

test/StaticJsonBuffer_ParseArray_Tests.cpp

@@ -5,12 +5,12 @@
 // https://github.com/bblanchon/ArduinoJson
 // If you like this project, please add a star!
 
-#include <gtest/gtest.h>
 #include <ArduinoJson.h>
+#include <gtest/gtest.h>
 
 class StaticJsonBuffer_ParseArray_Tests : public testing::Test {
  protected:
-  void with(JsonBuffer& jsonBuffer) {
+  void with(StaticJsonBufferBase& jsonBuffer) {
     _jsonBuffer = &jsonBuffer;
   }
 
@@ -27,7 +27,7 @@ class StaticJsonBuffer_ParseArray_Tests : public testing::Test {
   }
 
  private:
-  JsonBuffer* _jsonBuffer;
+  StaticJsonBufferBase* _jsonBuffer;
   char _jsonString[256];
 };
 
@@ -86,3 +86,11 @@ TEST_F(StaticJsonBuffer_ParseArray_Tests, ConstCharPtrNull) {
                    .parseArray(static_cast<const char*>(0))
                    .success());
 }
+
+TEST_F(StaticJsonBuffer_ParseArray_Tests, CopyStringNotSpaces) {
+  StaticJsonBuffer<100> jsonBuffer;
+  jsonBuffer.parseArray("  [ \"1234567\" ] ");
+  ASSERT_EQ(JSON_ARRAY_SIZE(1) + sizeof("1234567"), jsonBuffer.size());
+  // note we use a string of 8 bytes to be sure that the StaticJsonBuffer
+  // will not insert bytes to enforce alignement
+}

test/StaticJsonBuffer_ParseObject_Tests.cpp

@@ -10,7 +10,7 @@
 
 class StaticJsonBuffer_ParseObject_Tests : public testing::Test {
  protected:
-  void with(JsonBuffer& jsonBuffer) {
+  void with(StaticJsonBufferBase& jsonBuffer) {
     _jsonBuffer = &jsonBuffer;
   }
 
@@ -27,7 +27,7 @@ class StaticJsonBuffer_ParseObject_Tests : public testing::Test {
   }
 
  private:
-  JsonBuffer* _jsonBuffer;
+  StaticJsonBufferBase* _jsonBuffer;
   char _jsonString[256];
 };
 

test/StaticJsonBuffer_String_Tests.cpp

@@ -0,0 +1,48 @@
+// 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 <ArduinoJson.h>
+#include <gtest/gtest.h>
+
+TEST(StaticJsonBuffer_String_Tests, WorksWhenBufferIsBigEnough) {
+  StaticJsonBuffer<6> jsonBuffer;
+
+  StaticJsonBufferBase::String str = jsonBuffer.startString();
+  str.append('h');
+  str.append('e');
+  str.append('l');
+  str.append('l');
+  str.append('o');
+
+  ASSERT_STREQ("hello", str.c_str());
+}
+
+TEST(StaticJsonBuffer_String_Tests, ReturnsNullWhenTooSmall) {
+  StaticJsonBuffer<5> jsonBuffer;
+
+  StaticJsonBufferBase::String str = jsonBuffer.startString();
+  str.append('h');
+  str.append('e');
+  str.append('l');
+  str.append('l');
+  str.append('o');
+
+  ASSERT_EQ(NULL, str.c_str());
+}
+
+TEST(StaticJsonBuffer_String_Tests, SizeIncreases) {
+  StaticJsonBuffer<5> jsonBuffer;
+
+  StaticJsonBufferBase::String str = jsonBuffer.startString();
+  ASSERT_EQ(0, jsonBuffer.size());
+
+  str.append('h');
+  ASSERT_EQ(1, jsonBuffer.size());
+
+  str.c_str();
+  ASSERT_EQ(2, jsonBuffer.size());
+}