From 17b259df9cb6b28779d4881b2b6c805ee2e48eea Mon Sep 17 00:00:00 2001 From: Michele Calgaro Date: Fri, 7 Jun 2024 23:30:05 +0900 Subject: Rename to tde-ebook-reader Signed-off-by: Michele Calgaro --- reader/src/formats/pdb/BitReader.cpp | 57 ++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 reader/src/formats/pdb/BitReader.cpp (limited to 'reader/src/formats/pdb/BitReader.cpp') diff --git a/reader/src/formats/pdb/BitReader.cpp b/reader/src/formats/pdb/BitReader.cpp new file mode 100644 index 0000000..551aaf3 --- /dev/null +++ b/reader/src/formats/pdb/BitReader.cpp @@ -0,0 +1,57 @@ +/* + * Copyright (C) 2004-2012 Geometer Plus + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + */ + +#include +#include + +#include "BitReader.h" + +BitReader::BitReader(const unsigned char* data, std::size_t size) : myOffset(0), myLength(size * 8) { + myData = new unsigned char[size + 4]; + std::memcpy(myData, data, size); + std::memset(myData + size, 0x00, 4); +} + +BitReader::~BitReader() { + delete[] myData; +} + +unsigned long long BitReader::peek(std::size_t n) { + if (n > 32) { + return 0; + } + unsigned long long r = 0; + std::size_t g = 0; + while (g < n) { + r = (r << 8) | myData[(myOffset + g) >> 3]; + g = g + 8 - ((myOffset+g) & 7); + } + unsigned long long mask = 1; + mask = (mask << n) - 1; + return (r >> (g - n)) & mask; +} + +bool BitReader::eat(std::size_t n) { + myOffset += n; + return myOffset <= myLength; +} + +std::size_t BitReader::left() const { + return myLength - myOffset; +} -- cgit v1.2.3