[json] move json parser and stringifier into own compilation units.

src/json-parser.cc

-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef V8_JSON_PARSER_H_
-#define V8_JSON_PARSER_H_
+#include "src/json-parser.h"
 
-#include "src/char-predicates.h"
+#include "src/char-predicates-inl.h"
 #include "src/conversions.h"
 #include "src/debug/debug.h"
 #include "src/factory.h"
 #include "src/field-type.h"
 #include "src/messages.h"
+#include "src/objects-inl.h"
 #include "src/parsing/scanner.h"
 #include "src/parsing/token.h"
 #include "src/transitions.h"
 
 namespace v8 {
 namespace internal {
 
-enum ParseElementResult { kElementFound, kElementNotFound, kNullHandle };
+template <bool seq_one_byte>
+JsonParser<seq_one_byte>::JsonParser(Handle<String> source)
+    : source_(source),
+      source_length_(source->length()),
+      isolate_(source->map()->GetHeap()->isolate()),
+      factory_(isolate_->factory()),
+      zone_(isolate_->allocator()),
+      object_constructor_(isolate_->native_context()->object_function(),
+                          isolate_),
+      position_(-1) {
+  source_ = String::Flatten(source_);
+  pretenure_ = (source_length_ >= kPretenureTreshold) ? TENURED : NOT_TENURED;
 
-
-// A simple json parser.
-template <bool seq_one_byte>
-class JsonParser BASE_EMBEDDED {
- public:
-  MUST_USE_RESULT static MaybeHandle<Object> Parse(Handle<String> source) {
-    return JsonParser(source).ParseJson();
+  // Optimized fast case where we only have Latin1 characters.
+  if (seq_one_byte) {
+    seq_source_ = Handle<SeqOneByteString>::cast(source_);
   }
-
-  static const int kEndOfString = -1;
-
- private:
-  explicit JsonParser(Handle<String> source)
-      : source_(source),
-        source_length_(source->length()),
-        isolate_(source->map()->GetHeap()->isolate()),
-        factory_(isolate_->factory()),
-        zone_(isolate_->allocator()),
-        object_constructor_(isolate_->native_context()->object_function(),
-                            isolate_),
-        position_(-1) {
-    source_ = String::Flatten(source_);
-    pretenure_ = (source_length_ >= kPretenureTreshold) ? TENURED : NOT_TENURED;
-
-    // Optimized fast case where we only have Latin1 characters.
-    if (seq_one_byte) {
-      seq_source_ = Handle<SeqOneByteString>::cast(source_);
-    }
-  }
-
-  // Parse a string containing a single JSON value.
-  MaybeHandle<Object> ParseJson();
-
-  inline void Advance() {
-    position_++;
-    if (position_ >= source_length_) {
-      c0_ = kEndOfString;
-    } else if (seq_one_byte) {
-      c0_ = seq_source_->SeqOneByteStringGet(position_);
-    } else {
-      c0_ = source_->Get(position_);
-    }
-  }
-
-  // The JSON lexical grammar is specified in the ECMAScript 5 standard,
-  // section 15.12.1.1. The only allowed whitespace characters between tokens
-  // are tab, carriage-return, newline and space.
-
-  inline void AdvanceSkipWhitespace() {
-    do {
-      Advance();
-    } while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r');
-  }
-
-  inline void SkipWhitespace() {
-    while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r') {
-      Advance();
-    }
-  }
-
-  inline uc32 AdvanceGetChar() {
-    Advance();
-    return c0_;
-  }
-
-  // Checks that current charater is c.
-  // If so, then consume c and skip whitespace.
-  inline bool MatchSkipWhiteSpace(uc32 c) {
-    if (c0_ == c) {
-      AdvanceSkipWhitespace();
-      return true;
-    }
-    return false;
-  }
-
-  // A JSON string (production JSONString) is subset of valid JavaScript string
-  // literals. The string must only be double-quoted (not single-quoted), and
-  // the only allowed backslash-escapes are ", /, \, b, f, n, r, t and
-  // four-digit hex escapes (uXXXX). Any other use of backslashes is invalid.
-  Handle<String> ParseJsonString() {
-    return ScanJsonString<false>();
-  }
-
-  bool ParseJsonString(Handle<String> expected) {
-    int length = expected->length();
-    if (source_->length() - position_ - 1 > length) {
-      DisallowHeapAllocation no_gc;
-      String::FlatContent content = expected->GetFlatContent();
-      if (content.IsOneByte()) {
-        DCHECK_EQ('"', c0_);
-        const uint8_t* input_chars = seq_source_->GetChars() + position_ + 1;
-        const uint8_t* expected_chars = content.ToOneByteVector().start();
-        for (int i = 0; i < length; i++) {
-          uint8_t c0 = input_chars[i];
-          if (c0 != expected_chars[i] || c0 == '"' || c0 < 0x20 || c0 == '\\') {
-            return false;
-          }
-        }
-        if (input_chars[length] == '"') {
-          position_ = position_ + length + 1;
-          AdvanceSkipWhitespace();
-          return true;
-        }
-      }
-    }
-    return false;
-  }
-
-  Handle<String> ParseJsonInternalizedString() {
-    Handle<String> result = ScanJsonString<true>();
-    if (result.is_null()) return result;
-    return factory()->InternalizeString(result);
-  }
-
-  template <bool is_internalized>
-  Handle<String> ScanJsonString();
-  // Creates a new string and copies prefix[start..end] into the beginning
-  // of it. Then scans the rest of the string, adding characters after the
-  // prefix. Called by ScanJsonString when reaching a '\' or non-Latin1 char.
-  template <typename StringType, typename SinkChar>
-  Handle<String> SlowScanJsonString(Handle<String> prefix, int start, int end);
-
-  // A JSON number (production JSONNumber) is a subset of the valid JavaScript
-  // decimal number literals.
-  // It includes an optional minus sign, must have at least one
-  // digit before and after a decimal point, may not have prefixed zeros (unless
-  // the integer part is zero), and may include an exponent part (e.g., "e-10").
-  // Hexadecimal and octal numbers are not allowed.
-  Handle<Object> ParseJsonNumber();
-
-  // Parse a single JSON value from input (grammar production JSONValue).
-  // A JSON value is either a (double-quoted) string literal, a number literal,
-  // one of "true", "false", or "null", or an object or array literal.
-  Handle<Object> ParseJsonValue();
-
-  // Parse a JSON object literal (grammar production JSONObject).
-  // An object literal is a squiggly-braced and comma separated sequence
-  // (possibly empty) of key/value pairs, where the key is a JSON string
-  // literal, the value is a JSON value, and the two are separated by a colon.
-  // A JSON array doesn't allow numbers and identifiers as keys, like a
-  // JavaScript array.
-  Handle<Object> ParseJsonObject();
-
-  // Helper for ParseJsonObject. Parses the form "123": obj, which is recorded
-  // as an element, not a property.
-  ParseElementResult ParseElement(Handle<JSObject> json_object);
-
-  // Parses a JSON array literal (grammar production JSONArray). An array
-  // literal is a square-bracketed and comma separated sequence (possibly empty)
-  // of JSON values.
-  // A JSON array doesn't allow leaving out values from the sequence, nor does
-  // it allow a terminal comma, like a JavaScript array does.
-  Handle<Object> ParseJsonArray();
-
-
-  // Mark that a parsing error has happened at the current token, and
-  // return a null handle. Primarily for readability.
-  inline Handle<Object> ReportUnexpectedCharacter() {
-    return Handle<Object>::null();
-  }
-
-  inline Isolate* isolate() { return isolate_; }
-  inline Factory* factory() { return factory_; }
-  inline Handle<JSFunction> object_constructor() { return object_constructor_; }
-
-  static const int kInitialSpecialStringLength = 32;
-  static const int kPretenureTreshold = 100 * 1024;
-
-
- private:
-  Zone* zone() { return &zone_; }
-
-  void CommitStateToJsonObject(Handle<JSObject> json_object, Handle<Map> map,
-                               ZoneList<Handle<Object> >* properties);
-
-  Handle<String> source_;
-  int source_length_;
-  Handle<SeqOneByteString> seq_source_;
-
-  PretenureFlag pretenure_;
-  Isolate* isolate_;
-  Factory* factory_;
-  Zone zone_;
-  Handle<JSFunction> object_constructor_;
-  uc32 c0_;
-  int position_;
-};
+}
 
 template <bool seq_one_byte>
 MaybeHandle<Object> JsonParser<seq_one_byte>::ParseJson() {
   // Advance to the first character (possibly EOS)
   AdvanceSkipWhitespace();
   Handle<Object> result = ParseJsonValue();
   if (result.is_null() || c0_ != kEndOfString) {
     // Some exception (for example stack overflow) is already pending.
     if (isolate_->has_pending_exception()) return Handle<Object>::null();
 
@@ skipping 34 matching lines @@
     // We should sent compile error event because we compile JSON object in
     // separated source file.
     isolate()->debug()->OnCompileError(script);
     MessageLocation location(script, position_, position_ + 1);
     Handle<Object> error = factory->NewSyntaxError(message, arg1, arg2);
     return isolate()->template Throw<Object>(error, &location);
   }
   return result;
 }
 
+template <bool seq_one_byte>
+void JsonParser<seq_one_byte>::Advance() {
+  position_++;
+  if (position_ >= source_length_) {
+    c0_ = kEndOfString;
+  } else if (seq_one_byte) {
+    c0_ = seq_source_->SeqOneByteStringGet(position_);
+  } else {
+    c0_ = source_->Get(position_);
+  }
+}
+
+template <bool seq_one_byte>
+void JsonParser<seq_one_byte>::AdvanceSkipWhitespace() {
+  do {
+    Advance();
+  } while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r');
+}
+
+template <bool seq_one_byte>
+void JsonParser<seq_one_byte>::SkipWhitespace() {
+  while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r') {
+    Advance();
+  }
+}
+
+template <bool seq_one_byte>
+uc32 JsonParser<seq_one_byte>::AdvanceGetChar() {
+  Advance();
+  return c0_;
+}
+
+template <bool seq_one_byte>
+bool JsonParser<seq_one_byte>::MatchSkipWhiteSpace(uc32 c) {
+  if (c0_ == c) {
+    AdvanceSkipWhitespace();
+    return true;
+  }
+  return false;
+}
+
+template <bool seq_one_byte>
+bool JsonParser<seq_one_byte>::ParseJsonString(Handle<String> expected) {
+  int length = expected->length();
+  if (source_->length() - position_ - 1 > length) {
+    DisallowHeapAllocation no_gc;
+    String::FlatContent content = expected->GetFlatContent();
+    if (content.IsOneByte()) {
+      DCHECK_EQ('"', c0_);
+      const uint8_t* input_chars = seq_source_->GetChars() + position_ + 1;
+      const uint8_t* expected_chars = content.ToOneByteVector().start();
+      for (int i = 0; i < length; i++) {
+        uint8_t c0 = input_chars[i];
+        if (c0 != expected_chars[i] || c0 == '"' || c0 < 0x20 || c0 == '\\') {
+          return false;
+        }
+      }
+      if (input_chars[length] == '"') {
+        position_ = position_ + length + 1;
+        AdvanceSkipWhitespace();
+        return true;
+      }
+    }
+  }
+  return false;
+}
 
 // Parse any JSON value.
 template <bool seq_one_byte>
 Handle<Object> JsonParser<seq_one_byte>::ParseJsonValue() {
   StackLimitCheck stack_check(isolate_);
   if (stack_check.HasOverflowed()) {
     isolate_->StackOverflow();
     return Handle<Object>::null();
   }
 
@@ skipping 27 matching lines @@
     if (AdvanceGetChar() == 'u' && AdvanceGetChar() == 'l' &&
         AdvanceGetChar() == 'l') {
       AdvanceSkipWhitespace();
       return factory()->null_value();
     }
     return ReportUnexpectedCharacter();
   }
   return ReportUnexpectedCharacter();
 }
 
-
 template <bool seq_one_byte>
 ParseElementResult JsonParser<seq_one_byte>::ParseElement(
     Handle<JSObject> json_object) {
   uint32_t index = 0;
   // Maybe an array index, try to parse it.
   if (c0_ == '0') {
     // With a leading zero, the string has to be "0" only to be an index.
     Advance();
   } else {
     do {
@@ skipping 152 matching lines @@
         Handle<Object> value;
 
         key = ParseJsonInternalizedString();
         if (key.is_null() || c0_ != ':') return ReportUnexpectedCharacter();
 
         AdvanceSkipWhitespace();
         value = ParseJsonValue();
         if (value.is_null()) return ReportUnexpectedCharacter();
 
         JSObject::DefinePropertyOrElementIgnoreAttributes(json_object, key,
-                                                          value).Check();
+                                                          value)
+            .Check();
       }
     }
 
     if (c0_ != '}') {
       return ReportUnexpectedCharacter();
     }
   }
   AdvanceSkipWhitespace();
   return scope.CloseAndEscape(json_object);
 }
 
-
 template <bool seq_one_byte>
 void JsonParser<seq_one_byte>::CommitStateToJsonObject(
     Handle<JSObject> json_object, Handle<Map> map,
     ZoneList<Handle<Object> >* properties) {
   JSObject::AllocateStorageForMap(json_object, map);
   DCHECK(!json_object->map()->is_dictionary_map());
 
   DisallowHeapAllocation no_gc;
 
   int length = properties->length();
   for (int i = 0; i < length; i++) {
     Handle<Object> value = (*properties)[i];
     json_object->WriteToField(i, *value);
   }
 }
 
-
 // Parse a JSON array. Position must be right at '['.
 template <bool seq_one_byte>
 Handle<Object> JsonParser<seq_one_byte>::ParseJsonArray() {
   HandleScope scope(isolate());
   ZoneList<Handle<Object> > elements(4, zone());
   DCHECK_EQ(c0_, '[');
 
   AdvanceSkipWhitespace();
   if (c0_ != ']') {
     do {
@@ skipping 10 matching lines @@
   Handle<FixedArray> fast_elements =
       factory()->NewFixedArray(elements.length(), pretenure_);
   for (int i = 0, n = elements.length(); i < n; i++) {
     fast_elements->set(i, *elements[i]);
   }
   Handle<Object> json_array = factory()->NewJSArrayWithElements(
       fast_elements, FAST_ELEMENTS, pretenure_);
   return scope.CloseAndEscape(json_array);
 }
 
-
 template <bool seq_one_byte>
 Handle<Object> JsonParser<seq_one_byte>::ParseJsonNumber() {
   bool negative = false;
   int beg_pos = position_;
   if (c0_ == '-') {
     Advance();
     negative = true;
   }
   if (c0_ == '0') {
     Advance();
@@ skipping 25 matching lines @@
     Advance();
     if (c0_ == '-' || c0_ == '+') Advance();
     if (!IsDecimalDigit(c0_)) return ReportUnexpectedCharacter();
     do {
       Advance();
     } while (IsDecimalDigit(c0_));
   }
   int length = position_ - beg_pos;
   double number;
   if (seq_one_byte) {
-    Vector<const uint8_t> chars(seq_source_->GetChars() +  beg_pos, length);
+    Vector<const uint8_t> chars(seq_source_->GetChars() + beg_pos, length);
     number = StringToDouble(isolate()->unicode_cache(), chars,
                             NO_FLAGS,  // Hex, octal or trailing junk.
                             std::numeric_limits<double>::quiet_NaN());
   } else {
     Vector<uint8_t> buffer = Vector<uint8_t>::New(length);
     String::WriteToFlat(*source_, buffer.start(), beg_pos, position_);
     Vector<const uint8_t> result =
         Vector<const uint8_t>(buffer.start(), length);
-    number = StringToDouble(isolate()->unicode_cache(),
-                            result,
+    number = StringToDouble(isolate()->unicode_cache(), result,
                             NO_FLAGS,  // Hex, octal or trailing junk.
                             0.0);
     buffer.Dispose();
   }
   SkipWhitespace();
   return factory()->NewNumber(number, pretenure_);
 }
 
-
 template <typename StringType>
 inline void SeqStringSet(Handle<StringType> seq_str, int i, uc32 c);
 
 template <>
 inline void SeqStringSet(Handle<SeqTwoByteString> seq_str, int i, uc32 c) {
   seq_str->SeqTwoByteStringSet(i, c);
 }
 
 template <>
 inline void SeqStringSet(Handle<SeqOneByteString> seq_str, int i, uc32 c) {
   seq_str->SeqOneByteStringSet(i, c);
 }
 
 template <typename StringType>
-inline Handle<StringType> NewRawString(Factory* factory,
-                                       int length,
+inline Handle<StringType> NewRawString(Factory* factory, int length,
                                        PretenureFlag pretenure);
 
 template <>
-inline Handle<SeqTwoByteString> NewRawString(Factory* factory,
-                                             int length,
+inline Handle<SeqTwoByteString> NewRawString(Factory* factory, int length,
                                              PretenureFlag pretenure) {
   return factory->NewRawTwoByteString(length, pretenure).ToHandleChecked();
 }
 
 template <>
-inline Handle<SeqOneByteString> NewRawString(Factory* factory,
-                                           int length,
-                                           PretenureFlag pretenure) {
+inline Handle<SeqOneByteString> NewRawString(Factory* factory, int length,
+                                             PretenureFlag pretenure) {
   return factory->NewRawOneByteString(length, pretenure).ToHandleChecked();
 }
 
-
 // Scans the rest of a JSON string starting from position_ and writes
 // prefix[start..end] along with the scanned characters into a
 // sequential string of type StringType.
 template <bool seq_one_byte>
 template <typename StringType, typename SinkChar>
 Handle<String> JsonParser<seq_one_byte>::SlowScanJsonString(
     Handle<String> prefix, int start, int end) {
   int count = end - start;
   int max_length = count + source_length_ - position_;
   int length = Min(max_length, Max(kInitialSpecialStringLength, 2 * count));
@@ skipping 58 matching lines @@
           }
           if (sizeof(SinkChar) == kUC16Size ||
               value <= String::kMaxOneByteCharCode) {
             SeqStringSet(seq_string, count++, value);
             break;
           } else {
             // StringType is SeqOneByteString and we just read a non-Latin1
             // char.
             position_ -= 6;  // Rewind position_ to \ in \uxxxx.
             Advance();
-            return SlowScanJsonString<SeqTwoByteString, uc16>(seq_string,
-                                                              0,
+            return SlowScanJsonString<SeqTwoByteString, uc16>(seq_string, 0,
                                                               count);
           }
         }
         default:
           return Handle<String>::null();
       }
       Advance();
     }
   }
 
   DCHECK_EQ('"', c0_);
   // Advance past the last '"'.
   AdvanceSkipWhitespace();
 
   // Shrink seq_string length to count and return.
   return SeqString::Truncate(seq_string, count);
 }
 
-
 template <bool seq_one_byte>
 template <bool is_internalized>
 Handle<String> JsonParser<seq_one_byte>::ScanJsonString() {
   DCHECK_EQ('"', c0_);
   Advance();
   if (c0_ == '"') {
     AdvanceSkipWhitespace();
     return factory()->empty_string();
   }
 
   if (seq_one_byte && is_internalized) {
     // Fast path for existing internalized strings.  If the the string being
     // parsed is not a known internalized string, contains backslashes or
     // unexpectedly reaches the end of string, return with an empty handle.
     uint32_t running_hash = isolate()->heap()->HashSeed();
     int position = position_;
     uc32 c0 = c0_;
     do {
       if (c0 == '\\') {
         c0_ = c0;
         int beg_pos = position_;
         position_ = position;
-        return SlowScanJsonString<SeqOneByteString, uint8_t>(source_,
-                                                             beg_pos,
+        return SlowScanJsonString<SeqOneByteString, uint8_t>(source_, beg_pos,
                                                              position_);
       }
       if (c0 < 0x20) return Handle<String>::null();
       running_hash = StringHasher::AddCharacterCore(running_hash,
                                                     static_cast<uint16_t>(c0));
       position++;
       if (position >= source_length_) return Handle<String>::null();
       c0 = seq_source_->SeqOneByteStringGet(position);
     } while (c0 != '"');
     int length = position - position_;
     uint32_t hash = (length <= String::kMaxHashCalcLength)
                         ? StringHasher::GetHashCore(running_hash)
                         : static_cast<uint32_t>(length);
-    Vector<const uint8_t> string_vector(
-        seq_source_->GetChars() + position_, length);
+    Vector<const uint8_t> string_vector(seq_source_->GetChars() + position_,
+                                        length);
     StringTable* string_table = isolate()->heap()->string_table();
     uint32_t capacity = string_table->Capacity();
     uint32_t entry = StringTable::FirstProbe(hash, capacity);
     uint32_t count = 1;
     Handle<String> result;
     while (true) {
       Object* element = string_table->KeyAt(entry);
       if (element == isolate()->heap()->undefined_value()) {
         // Lookup failure.
-        result = factory()->InternalizeOneByteString(
-            seq_source_, position_, length);
+        result =
+            factory()->InternalizeOneByteString(seq_source_, position_, length);
         break;
       }
       if (element != isolate()->heap()->the_hole_value() &&
           String::cast(element)->IsOneByteEqualTo(string_vector)) {
         result = Handle<String>(String::cast(element), isolate());
 #ifdef DEBUG
         uint32_t hash_field =
             (hash << String::kHashShift) | String::kIsNotArrayIndexMask;
         DCHECK_EQ(static_cast<int>(result->Hash()),
                   static_cast<int>(hash_field >> String::kHashShift));
@@ skipping 10 matching lines @@
 
   int beg_pos = position_;
   // Fast case for Latin1 only without escape characters.
   do {
     // Check for control character (0x00-0x1f) or unterminated string (<0).
     if (c0_ < 0x20) return Handle<String>::null();
     if (c0_ != '\\') {
       if (seq_one_byte || c0_ <= String::kMaxOneByteCharCode) {
         Advance();
       } else {
-        return SlowScanJsonString<SeqTwoByteString, uc16>(source_,
-                                                          beg_pos,
+        return SlowScanJsonString<SeqTwoByteString, uc16>(source_, beg_pos,
                                                           position_);
       }
     } else {
-      return SlowScanJsonString<SeqOneByteString, uint8_t>(source_,
-                                                           beg_pos,
+      return SlowScanJsonString<SeqOneByteString, uint8_t>(source_, beg_pos,
                                                            position_);
     }
   } while (c0_ != '"');
   int length = position_ - beg_pos;
   Handle<String> result =
       factory()->NewRawOneByteString(length, pretenure_).ToHandleChecked();
   uint8_t* dest = SeqOneByteString::cast(*result)->GetChars();
   String::WriteToFlat(*source_, dest, beg_pos, position_);
 
   DCHECK_EQ('"', c0_);
   // Advance past the last '"'.
   AdvanceSkipWhitespace();
   return result;
 }
 
+// Explicit instantiation.
+template class JsonParser<true>;
+template class JsonParser<false>;
+
 }  // namespace internal
 }  // namespace v8
-
-#endif  // V8_JSON_PARSER_H_