Parser / Scanner: Minor refactorings to make streaming scripts work easier.

src/scanner-character-streams.cc

 // Copyright 2011 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.
 
 #include "src/v8.h"
 
 #include "src/scanner-character-streams.h"
 
 #include "src/handles.h"
 #include "src/unicode-inl.h"
@@ skipping 60 matching lines @@
   buffer_cursor_ = buffer_;
   if (pushback_limit_ != NULL) {
     // Leave pushback mode.
     buffer_end_ = pushback_limit_;
     pushback_limit_ = NULL;
     // If there were any valid characters left at the
     // start of the buffer, use those.
     if (buffer_cursor_ < buffer_end_) return true;
     // Otherwise read a new block.
   }
-  unsigned length = FillBuffer(pos_, kBufferSize);
+  unsigned length = FillBuffer(pos_);
   buffer_end_ = buffer_ + length;
   return length > 0;
 }
 
 
 unsigned BufferedUtf16CharacterStream::SlowSeekForward(unsigned delta) {
   // Leave pushback mode (i.e., ignore that there might be valid data
   // in the buffer before the pushback_limit_ point).
   pushback_limit_ = NULL;
   return BufferSeekForward(delta);
@@ skipping 19 matching lines @@
 
 
 unsigned GenericStringUtf16CharacterStream::BufferSeekForward(unsigned delta) {
   unsigned old_pos = pos_;
   pos_ = Min(pos_ + delta, length_);
   ReadBlock();
   return pos_ - old_pos;
 }
 
 
-unsigned GenericStringUtf16CharacterStream::FillBuffer(unsigned from_pos,
-                                                      unsigned length) {
+unsigned GenericStringUtf16CharacterStream::FillBuffer(unsigned from_pos) {
   if (from_pos >= length_) return 0;
+  unsigned length = kBufferSize;
   if (from_pos + length > length_) {
     length = length_ - from_pos;
   }
   String::WriteToFlat<uc16>(*string_, buffer_, from_pos, from_pos + length);
   return length;
 }
 
 
 // ----------------------------------------------------------------------------
 // Utf8ToUtf16CharacterStream
@@ skipping 14 matching lines @@
 unsigned Utf8ToUtf16CharacterStream::BufferSeekForward(unsigned delta) {
   unsigned old_pos = pos_;
   unsigned target_pos = pos_ + delta;
   SetRawPosition(target_pos);
   pos_ = raw_character_position_;
   ReadBlock();
   return pos_ - old_pos;
 }
 
 
-unsigned Utf8ToUtf16CharacterStream::FillBuffer(unsigned char_position,
-                                                unsigned length) {
+unsigned Utf8ToUtf16CharacterStream::FillBuffer(unsigned char_position) {
   static const unibrow::uchar kMaxUtf16Character = 0xffff;
   SetRawPosition(char_position);
   if (raw_character_position_ != char_position) {
     // char_position was not a valid position in the stream (hit the end
     // while spooling to it).
     return 0u;
   }
   unsigned i = 0;
-  while (i < length - 1) {
+  while (i < kBufferSize - 1) {
     if (raw_data_pos_ == raw_data_length_) break;
     unibrow::uchar c = raw_data_[raw_data_pos_];
     if (c <= unibrow::Utf8::kMaxOneByteChar) {
       raw_data_pos_++;
     } else {
       c =  unibrow::Utf8::CalculateValue(raw_data_ + raw_data_pos_,
                                          raw_data_length_ - raw_data_pos_,
                                          &raw_data_pos_);
     }
     if (c > kMaxUtf16Character) {
@@ skipping 112 matching lines @@
         int end_position)
     : Utf16CharacterStream(),
       source_(data),
       raw_data_(data->GetTwoByteData(start_position)) {
   buffer_cursor_ = raw_data_,
   buffer_end_ = raw_data_ + (end_position - start_position);
   pos_ = start_position;
 }
 
 } }  // namespace v8::internal