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authorMichele Calgaro <michele.calgaro@yahoo.it>2024-05-11 21:28:48 +0900
committerMichele Calgaro <michele.calgaro@yahoo.it>2024-05-11 21:28:48 +0900
commit2462d03f322261bd616721c2b2065c4004b36c9c (patch)
tree239947a0737bb8386703a1497f12c09aebd3080a /fbreader/src/formats/chm/HuffmanDecoder.cpp
downloadtde-ebook-reader-2462d03f322261bd616721c2b2065c4004b36c9c.tar.gz
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Initial import (as is) from Debian Snapshot's 'fbreader' source code (https://snapshot.debian.org/package/fbreader/0.99.4%2Bdfsg-6).
The Debian code is provided under GPL2 license. Signed-off-by: Michele Calgaro <michele.calgaro@yahoo.it>
Diffstat (limited to 'fbreader/src/formats/chm/HuffmanDecoder.cpp')
-rw-r--r--fbreader/src/formats/chm/HuffmanDecoder.cpp60
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diff --git a/fbreader/src/formats/chm/HuffmanDecoder.cpp b/fbreader/src/formats/chm/HuffmanDecoder.cpp
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+++ b/fbreader/src/formats/chm/HuffmanDecoder.cpp
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+/*
+ * Copyright (C) 2004-2012 Geometer Plus <contact@geometerplus.com>
+ *
+ * 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 <algorithm>
+
+#include "HuffmanDecoder.h"
+
+HuffmanDecoder::HuffmanDecoder() : myMaxBitsNumber(0) {
+}
+
+void HuffmanDecoder::reset() {
+ CodeLengths.clear();
+}
+
+bool HuffmanDecoder::buildTable() {
+ myMaxBitsNumber = 0;
+ for (unsigned short symbol = 0; symbol < CodeLengths.size(); symbol++) {
+ myMaxBitsNumber = std::max(CodeLengths[symbol], myMaxBitsNumber);
+ }
+ if (myMaxBitsNumber > 16) {
+ return false;
+ }
+
+ unsigned int tableSize = 1 << myMaxBitsNumber;
+ mySymbols.clear();
+ mySymbols.reserve(tableSize);
+
+ for (unsigned char i = 1; i <= myMaxBitsNumber; ++i) {
+ for (unsigned short symbol = 0; symbol < CodeLengths.size(); symbol++) {
+ if (CodeLengths[symbol] == i) {
+ mySymbols.insert(mySymbols.end(), 1 << (myMaxBitsNumber - i), symbol);
+ if (mySymbols.size() > tableSize) {
+ return false;
+ }
+ }
+ }
+ }
+
+ if (mySymbols.size() < tableSize) {
+ mySymbols.insert(mySymbols.end(), tableSize - mySymbols.size(), 0);
+ }
+
+ return true;
+}