Buffer.cpp

#include "Buffer.h"
#include "Util.h"
#include <algorithm>
#include <cstring>
#include <iostream>

namespace khaki{

Buffer::Buffer() : buf_(NULL), begin_(0), end_(0), cap_(0), size_(0) {

}

Buffer::Buffer(std::string& str)
{
	append(str.data(), str.size());
}

Buffer::Buffer(const Buffer& buf)
{
	buf_ = new char[buf.size()];
	memcpy(buf_, buf.buf_, (size_t)buf.size());
	begin_ = 0;
	end_ = buf.size();
	cap_ = buf.size();
	size_ = buf.size();
}

Buffer::~Buffer() {
	if (buf_) delete[] buf_;
}

void Buffer::clear() {
	size_ = 0;
	begin_ = 0;
	end_ = 0;
}

bool Buffer::empty() const {
	return (end_ - begin_ > 0) ? false : true;
}

uint32_t Buffer::size() const {
	return end_ - begin_;
}

char* Buffer::begin() const {
	return buf_ + begin_;
}

char* Buffer::end() const {
	return buf_ + end_;
}

char* Buffer::data() {
	return buf_ + begin_;
}

void Buffer::move()
{
	std::copy(begin(), end(), buf_);
	end_ -= begin_;
	begin_ = 0;
}

void Buffer::append(const char* buf, uint32_t len)
{
	move();
	if (end_ + len > cap_) alloc(end_ + len);
	std::copy(buf, buf + len, end());
	end_ += len;
}

void Buffer::alloc(uint32_t len)
{
	char* bufTemp = new char[2 * len];
	memset(bufTemp, 0, 2 * len);
	std::copy(begin(), end(), bufTemp);
	delete[] buf_;
	buf_ = bufTemp;
	end_ -= begin_;
	begin_ = 0;
	cap_ = 2 * len;
}

void Buffer::addBegin(uint32_t len)
{
	if ( len >= size() ) {
		begin_ += size();
		return;
	}

	begin_ += len;

	if ( begin_ == end_ ) {
		begin_ = 0;
		end_ = 0;
	}
}

std::string Buffer::show()
{
	return util::string_format("[%d %d %d]", begin_, end_, cap_);
}
}