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// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#ifndef RUNTIME_PLATFORM_TEXT_BUFFER_H_
#define RUNTIME_PLATFORM_TEXT_BUFFER_H_
#include "platform/allocation.h"
#include "platform/globals.h"
namespace dart {
// BaseTextBuffer maintains a dynamic character buffer with a printf-style way
// to append text. Internal buffer management is handled by subclasses.
class BaseTextBuffer : public ValueObject {
public:
BaseTextBuffer() : buffer_(nullptr), capacity_(0), length_(0) {}
BaseTextBuffer(char* buffer, intptr_t capacity)
: buffer_(buffer), capacity_(capacity), length_(0) {}
virtual ~BaseTextBuffer() {}
intptr_t Printf(const char* format, ...) PRINTF_ATTRIBUTE(2, 3);
void AddChar(char ch);
void EscapeAndAddUTF16CodeUnit(uint16_t cu);
void EscapeAndAddCodeUnit(uint32_t cu);
void AddString(const char* s);
void AddEscapedString(const char* s);
void AddRaw(const uint8_t* buffer, intptr_t buffer_length);
// Returns a pointer to the current internal buffer. Whether the pointer is
// still valid after the BaseTextBuffer dies depends on the subclass.
char* buffer() const { return buffer_; }
intptr_t length() const { return length_; }
// Clears the stored contents. Unless specified otherwise by the subclass,
// should be assumed to invalidate the contents of previous calls to buffer().
virtual void Clear() = 0;
protected:
virtual bool EnsureCapacity(intptr_t len) = 0;
char* buffer_;
intptr_t capacity_;
intptr_t length_;
DISALLOW_COPY_AND_ASSIGN(BaseTextBuffer);
};
// TextBuffer uses manual memory management for the character buffer. Unless
// Steal() is used, the internal buffer is deallocated when the object dies.
class TextBuffer : public BaseTextBuffer {
public:
explicit TextBuffer(intptr_t buf_size);
~TextBuffer();
// Resets the contents of the internal buffer.
void Clear() { set_length(0); }
void set_length(intptr_t len) {
ASSERT(len >= 0);
ASSERT(len <= length_);
length_ = len;
buffer_[len] = '\0';
}
// Take ownership of the buffer contents. Future uses of the TextBuffer object
// will not affect the contents of the returned buffer.
// NOTE: TextBuffer is empty afterwards.
char* Steal();
private:
bool EnsureCapacity(intptr_t len);
DISALLOW_COPY_AND_ASSIGN(TextBuffer);
};
class BufferFormatter : public BaseTextBuffer {
public:
BufferFormatter(char* buffer, intptr_t size) : BaseTextBuffer(buffer, size) {
buffer_[length_] = '\0';
}
void Clear() {
length_ = 0;
buffer_[length_] = '\0';
}
private:
// We can't extend, so only return true if there's room.
bool EnsureCapacity(intptr_t len) { return length_ + len <= capacity_ - 1; }
DISALLOW_COPY_AND_ASSIGN(BufferFormatter);
};
} // namespace dart
#endif // RUNTIME_PLATFORM_TEXT_BUFFER_H_