Remove some old forge hacks

Forge apparently removed all `.pack.xz` files without warning.
It broke a bunch of stuff, as always. But it also means we don't need some ugly code anymore.

This is removed:

- Support for 'forge-pack-xz' and the forge-specific file download compression.
- The pack200 library we no longer need.

This stays:

- The LZMA decompression library - we may still want to use it.

26 files changed, 10 insertions, 10528 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d02dfc8b..747ec5c8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -248,7 +248,6 @@ add_subdirectory(libraries/launcher) # java based launcher part for Minecraft
 add_subdirectory(libraries/javacheck) # java compatibility checker
 add_subdirectory(libraries/xz-embedded) # xz compression
 add_subdirectory(libraries/quazip) # zip manipulation library
-add_subdirectory(libraries/pack200) # java pack200 compression
 add_subdirectory(libraries/rainbow) # Qt extension for colors
 add_subdirectory(libraries/iconfix) # fork of Qt's QIcon loader
 add_subdirectory(libraries/LocalPeer) # fork of a library from Qt solutions
diff --git a/COPYING.md b/COPYING.md
index 8aa7e75e..70ff7ce2 100644
--- a/COPYING.md
+++ b/COPYING.md
@@ -128,35 +128,6 @@
     This license is copied below, and is also available with a FAQ at:
     http://scripts.sil.org/OFL
 
-# Pack200
-
-    The GNU General Public License (GPL)
-
-    Version 2, June 1991
-
-    + "CLASSPATH" EXCEPTION TO THE GPL
-
-    Certain source files distributed by Oracle America and/or its affiliates are
-    subject to the following clarification and special exception to the GPL, but
-    only where Oracle has expressly included in the particular source file's header
-    the words "Oracle designates this particular file as subject to the "Classpath"
-    exception as provided by Oracle in the LICENSE file that accompanied this code."
-
-    Linking this library statically or dynamically with other modules is making
-    a combined work based on this library.  Thus, the terms and conditions of
-    the GNU General Public License cover the whole combination.
-
-    As a special exception, the copyright holders of this library give you
-    permission to link this library with independent modules to produce an
-    executable, regardless of the license terms of these independent modules,
-    and to copy and distribute the resulting executable under terms of your
-    choice, provided that you also meet, for each linked independent module,
-    the terms and conditions of the license of that module.  An independent
-    module is a module which is not derived from or based on this library.  If
-    you modify this library, you may extend this exception to your version of
-    the library, but you are not obligated to do so.  If you do not wish to do
-    so, delete this exception statement from your version.
-
 # Quazip
 
     Copyright (C) 2005-2011 Sergey A. Tachenov
diff --git a/api/logic/CMakeLists.txt b/api/logic/CMakeLists.txt
index 995c9d4e..50c2cb6e 100644
--- a/api/logic/CMakeLists.txt
+++ b/api/logic/CMakeLists.txt
@@ -305,10 +305,6 @@ set(MINECRAFT_SOURCES
     minecraft/AssetsUtils.h
     minecraft/AssetsUtils.cpp
 
-    # Forge and all things forge related
-    minecraft/forge/ForgeXzDownload.h
-    minecraft/forge/ForgeXzDownload.cpp
-
     # Skin upload utilities
     minecraft/SkinUpload.cpp
     minecraft/SkinUpload.h
@@ -495,7 +491,7 @@ set_target_properties(MultiMC_logic PROPERTIES CXX_VISIBILITY_PRESET hidden VISI
 generate_export_header(MultiMC_logic)
 
 # Link
-target_link_libraries(MultiMC_logic xz-embedded MultiMC_unpack200 systeminfo MultiMC_quazip MultiMC_classparser ${NBT_NAME} ${ZLIB_LIBRARIES})
+target_link_libraries(MultiMC_logic systeminfo MultiMC_quazip MultiMC_classparser ${NBT_NAME} ${ZLIB_LIBRARIES})
 target_link_libraries(MultiMC_logic Qt5::Core Qt5::Xml Qt5::Network Qt5::Concurrent)
 
 # Mark and export headers
diff --git a/api/logic/minecraft/Library.cpp b/api/logic/minecraft/Library.cpp
index a56e8110..9ff8dcdc 100644
--- a/api/logic/minecraft/Library.cpp
+++ b/api/logic/minecraft/Library.cpp
@@ -3,7 +3,6 @@
 
 #include <net/Download.h>
 #include <net/ChecksumValidator.h>
-#include <minecraft/forge/ForgeXzDownload.h>
 #include <Env.h>
 #include <FileSystem.h>
 
@@ -88,26 +87,19 @@ QList< std::shared_ptr< NetAction > > Library::getDownloads(
         {
             options |= Net::Download::Option::AcceptLocalFiles;
         }
-        if (isForge())
+
+        if(sha1.size())
         {
-            qDebug() << "XzDownload for:" << rawName() << "storage:" << storage << "url:" << url;
-            out.append(ForgeXzDownload::make(url, storage, entry));
+            auto rawSha1 = QByteArray::fromHex(sha1.toLatin1());
+            auto dl = Net::Download::makeCached(url, entry, options);
+            dl->addValidator(new Net::ChecksumValidator(QCryptographicHash::Sha1, rawSha1));
+            qDebug() << "Checksummed Download for:" << rawName() << "storage:" << storage << "url:" << url;
+            out.append(dl);
         }
         else
         {
-            if(sha1.size())
-            {
-                auto rawSha1 = QByteArray::fromHex(sha1.toLatin1());
-                auto dl = Net::Download::makeCached(url, entry, options);
-                dl->addValidator(new Net::ChecksumValidator(QCryptographicHash::Sha1, rawSha1));
-                qDebug() << "Checksummed Download for:" << rawName() << "storage:" << storage << "url:" << url;
-                out.append(dl);
-            }
-            else
-            {
-                out.append(Net::Download::makeCached(url, entry, options));
-                qDebug() << "Download for:" << rawName() << "storage:" << storage << "url:" << url;
-            }
+            out.append(Net::Download::makeCached(url, entry, options));
+            qDebug() << "Download for:" << rawName() << "storage:" << storage << "url:" << url;
         }
         return true;
     };
@@ -243,11 +235,6 @@ bool Library::isAlwaysStale() const
     return m_hint == "always-stale";
 }
 
-bool Library::isForge() const
-{
-    return m_hint == "forge-pack-xz";
-}
-
 void Library::setStoragePrefix(QString prefix)
 {
     m_storagePrefix = prefix;
diff --git a/api/logic/minecraft/MinecraftUpdate.cpp b/api/logic/minecraft/MinecraftUpdate.cpp
index 00558e37..f9ff114d 100644
--- a/api/logic/minecraft/MinecraftUpdate.cpp
+++ b/api/logic/minecraft/MinecraftUpdate.cpp
@@ -14,7 +14,6 @@
  */
 
 #include "Env.h"
-#include <minecraft/forge/ForgeXzDownload.h>
 #include "MinecraftUpdate.h"
 #include "MinecraftInstance.h"
 
diff --git a/api/logic/minecraft/forge/ForgeXzDownload.cpp b/api/logic/minecraft/forge/ForgeXzDownload.cpp
deleted file mode 100644
index c6465469..00000000
--- a/api/logic/minecraft/forge/ForgeXzDownload.cpp
+++ /dev/null
@@ -1,393 +0,0 @@
-/* Copyright 2013-2019 MultiMC Contributors
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "Env.h"
-#include "ForgeXzDownload.h"
-#include <FileSystem.h>
-
-#include <QCryptographicHash>
-#include <QFileInfo>
-#include <QDateTime>
-#include <QDir>
-#include <QDebug>
-
-ForgeXzDownload::ForgeXzDownload(QString url, QString relative_path, MetaEntryPtr entry) : NetAction()
-{
-    m_entry = entry;
-    m_target_path = entry->getFullPath();
-    m_pack200_xz_file.setFileTemplate("./dl_temp.XXXXXX");
-    m_status = Job_NotStarted;
-    m_url_path = relative_path;
-    m_url = url + ".pack.xz";
-}
-
-void ForgeXzDownload::start()
-{
-    if(m_status == Job_Aborted)
-    {
-        qWarning() << "Attempt to start an aborted Download:" << m_url.toString();
-        emit aborted(m_index_within_job);
-        return;
-    }
-    m_status = Job_InProgress;
-    if (!m_entry->isStale())
-    {
-        m_status = Job_Finished;
-        emit succeeded(m_index_within_job);
-        return;
-    }
-    // can we actually create the real, final file?
-    if (!FS::ensureFilePathExists(m_target_path))
-    {
-        m_status = Job_Failed;
-        emit failed(m_index_within_job);
-        return;
-    }
-
-    qDebug() << "Downloading " << m_url.toString();
-    QNetworkRequest request(m_url);
-    request.setRawHeader(QString("If-None-Match").toLatin1(), m_entry->getETag().toLatin1());
-    request.setHeader(QNetworkRequest::UserAgentHeader, "MultiMC/5.0 (Cached)");
-
-    QNetworkReply *rep = ENV.qnam().get(request);
-
-    m_reply.reset(rep);
-    connect(rep, SIGNAL(downloadProgress(qint64, qint64)), SLOT(downloadProgress(qint64, qint64)));
-    connect(rep, SIGNAL(finished()), SLOT(downloadFinished()));
-    connect(rep, SIGNAL(error(QNetworkReply::NetworkError)), SLOT(downloadError(QNetworkReply::NetworkError)));
-    connect(rep, SIGNAL(readyRead()), SLOT(downloadReadyRead()));
-}
-
-void ForgeXzDownload::downloadProgress(qint64 bytesReceived, qint64 bytesTotal)
-{
-    m_total_progress = bytesTotal;
-    m_progress = bytesReceived;
-    emit netActionProgress(m_index_within_job, bytesReceived, bytesTotal);
-}
-
-void ForgeXzDownload::downloadError(QNetworkReply::NetworkError error)
-{
-    if(error == QNetworkReply::OperationCanceledError)
-    {
-        qCritical() << "Aborted " << m_url.toString();
-        m_status = Job_Aborted;
-    }
-    else
-    {
-        // error happened during download.
-        qCritical() << "Failed " << m_url.toString() << " with reason " << error;
-        m_status = Job_Failed;
-    }
-}
-
-void ForgeXzDownload::failAndTryNextMirror()
-{
-    m_status = Job_Failed;
-    emit failed(m_index_within_job);
-}
-
-void ForgeXzDownload::downloadFinished()
-{
-    // if the download succeeded
-    if (m_status != Job_Failed && m_status != Job_Aborted)
-    {
-        // nothing went wrong...
-        m_status = Job_Finished;
-        if (m_pack200_xz_file.isOpen())
-        {
-            // we actually downloaded something! process and isntall it
-            decompressAndInstall();
-            return;
-        }
-        else
-        {
-            // something bad happened -- on the local machine!
-            m_status = Job_Failed;
-            m_pack200_xz_file.remove();
-            m_reply.reset();
-            emit failed(m_index_within_job);
-            return;
-        }
-    }
-    else if(m_status == Job_Aborted)
-    {
-        m_pack200_xz_file.remove();
-        m_reply.reset();
-        emit failed(m_index_within_job);
-        emit aborted(m_index_within_job);
-        return;
-    }
-    // else the download failed
-    else
-    {
-        m_status = Job_Failed;
-        m_pack200_xz_file.close();
-        m_pack200_xz_file.remove();
-        m_reply.reset();
-        failAndTryNextMirror();
-        return;
-    }
-}
-
-void ForgeXzDownload::downloadReadyRead()
-{
-
-    if (!m_pack200_xz_file.isOpen())
-    {
-        if (!m_pack200_xz_file.open())
-        {
-            /*
-            * Can't open the file... the job failed
-            */
-            m_reply->abort();
-            emit failed(m_index_within_job);
-            return;
-        }
-    }
-    m_pack200_xz_file.write(m_reply->readAll());
-}
-
-#include "xz.h"
-#include "unpack200.h"
-#include <stdexcept>
-#include <unistd.h>
-
-const size_t buffer_size = 8196;
-
-// NOTE: once this gets here, it can't be aborted anymore. we don't care.
-void ForgeXzDownload::decompressAndInstall()
-{
-    // rewind the downloaded temp file
-    m_pack200_xz_file.seek(0);
-    // de-xz'd file
-    QTemporaryFile pack200_file("./dl_temp.XXXXXX");
-    pack200_file.open();
-
-    bool xz_success = false;
-    // first, de-xz
-    {
-        uint8_t in[buffer_size];
-        uint8_t out[buffer_size];
-        struct xz_buf b;
-        struct xz_dec *s;
-        enum xz_ret ret;
-        xz_crc32_init();
-        xz_crc64_init();
-        s = xz_dec_init(XZ_DYNALLOC, 1 << 26);
-        if (s == nullptr)
-        {
-            xz_dec_end(s);
-            failAndTryNextMirror();
-            return;
-        }
-        b.in = in;
-        b.in_pos = 0;
-        b.in_size = 0;
-        b.out = out;
-        b.out_pos = 0;
-        b.out_size = buffer_size;
-        while (!xz_success)
-        {
-            if (b.in_pos == b.in_size)
-            {
-                b.in_size = m_pack200_xz_file.read((char *)in, sizeof(in));
-                b.in_pos = 0;
-            }
-
-            ret = xz_dec_run(s, &b);
-
-            if (b.out_pos == sizeof(out))
-            {
-                auto wresult = pack200_file.write((char *)out, b.out_pos);
-                if (wresult < 0 || size_t(wresult) != b.out_pos)
-                {
-                    // msg = "Write error\n";
-                    xz_dec_end(s);
-                    failAndTryNextMirror();
-                    return;
-                }
-
-                b.out_pos = 0;
-            }
-
-            if (ret == XZ_OK)
-                continue;
-
-            if (ret == XZ_UNSUPPORTED_CHECK)
-            {
-                // unsupported check. this is OK, but we should log this
-                continue;
-            }
-
-            auto wresult = pack200_file.write((char *)out, b.out_pos);
-            if (wresult < 0 || size_t(wresult) != b.out_pos)
-            {
-                // write error
-                pack200_file.close();
-                xz_dec_end(s);
-                return;
-            }
-
-            switch (ret)
-            {
-            case XZ_STREAM_END:
-                xz_dec_end(s);
-                xz_success = true;
-                break;
-
-            case XZ_MEM_ERROR:
-                qCritical() << "Memory allocation failed\n";
-                xz_dec_end(s);
-                failAndTryNextMirror();
-                return;
-
-            case XZ_MEMLIMIT_ERROR:
-                qCritical() << "Memory usage limit reached\n";
-                xz_dec_end(s);
-                failAndTryNextMirror();
-                return;
-
-            case XZ_FORMAT_ERROR:
-                qCritical() << "Not a .xz file\n";
-                xz_dec_end(s);
-                failAndTryNextMirror();
-                return;
-
-            case XZ_OPTIONS_ERROR:
-                qCritical() << "Unsupported options in the .xz headers\n";
-                xz_dec_end(s);
-                failAndTryNextMirror();
-                return;
-
-            case XZ_DATA_ERROR:
-            case XZ_BUF_ERROR:
-                qCritical() << "File is corrupt\n";
-                xz_dec_end(s);
-                failAndTryNextMirror();
-                return;
-
-            default:
-                qCritical() << "Bug!\n";
-                xz_dec_end(s);
-                failAndTryNextMirror();
-                return;
-            }
-        }
-    }
-    m_pack200_xz_file.remove();
-
-    // revert pack200
-    pack200_file.seek(0);
-    int handle_in = pack200_file.handle();
-    // FIXME: dispose of file handles, pointers and the like. Ideally wrap in objects.
-    if(handle_in == -1)
-    {
-        qCritical() << "Error reopening " << pack200_file.fileName();
-        failAndTryNextMirror();
-        return;
-    }
-    int handle_in_dup = dup (handle_in);
-    if(handle_in_dup == -1)
-    {
-        qCritical() << "Error reopening " << pack200_file.fileName();
-        failAndTryNextMirror();
-        return;
-    }
-    FILE *file_in = fdopen (handle_in_dup, "rb");
-    if(!file_in)
-    {
-        qCritical() << "Error reopening " << pack200_file.fileName();
-        failAndTryNextMirror();
-        return;
-    }
-    QFile qfile_out(m_target_path);
-    if(!qfile_out.open(QIODevice::WriteOnly))
-    {
-        qCritical() << "Error opening " << qfile_out.fileName();
-        failAndTryNextMirror();
-        return;
-    }
-    int handle_out = qfile_out.handle();
-    if(handle_out == -1)
-    {
-        qCritical() << "Error opening " << qfile_out.fileName();
-        failAndTryNextMirror();
-        return;
-    }
-    int handle_out_dup = dup (handle_out);
-    if(handle_out_dup == -1)
-    {
-        qCritical() << "Error reopening " << qfile_out.fileName();
-        failAndTryNextMirror();
-        return;
-    }
-    FILE *file_out = fdopen (handle_out_dup, "wb");
-    if(!file_out)
-    {
-        qCritical() << "Error opening " << qfile_out.fileName();
-        failAndTryNextMirror();
-        return;
-    }
-    try
-    {
-        // NOTE: this takes ownership of both FILE pointers. That's why we duplicate them above.
-        unpack_200(file_in, file_out);
-    }
-    catch (const std::runtime_error &err)
-    {
-        m_status = Job_Failed;
-        qCritical() << "Error unpacking " << pack200_file.fileName() << " : " << err.what();
-        QFile f(m_target_path);
-        if (f.exists())
-            f.remove();
-        failAndTryNextMirror();
-        return;
-    }
-    pack200_file.remove();
-
-    QFile jar_file(m_target_path);
-
-    if (!jar_file.open(QIODevice::ReadOnly))
-    {
-        jar_file.remove();
-        failAndTryNextMirror();
-        return;
-    }
-    auto hash = QCryptographicHash::hash(jar_file.readAll(), QCryptographicHash::Md5);
-    m_entry->setMD5Sum(hash.toHex().constData());
-    jar_file.close();
-
-    QFileInfo output_file_info(m_target_path);
-    m_entry->setETag(m_reply->rawHeader("ETag").constData());
-    m_entry->setLocalChangedTimestamp(output_file_info.lastModified().toUTC().toMSecsSinceEpoch());
-    m_entry->setStale(false);
-    ENV.metacache()->updateEntry(m_entry);
-
-    m_reply.reset();
-    emit succeeded(m_index_within_job);
-}
-
-bool ForgeXzDownload::abort()
-{
-    if(m_reply)
-        m_reply->abort();
-    m_status = Job_Aborted;
-    return true;
-}
-
-bool ForgeXzDownload::canAbort()
-{
-    return true;
-}
diff --git a/api/logic/minecraft/forge/ForgeXzDownload.h b/api/logic/minecraft/forge/ForgeXzDownload.h
deleted file mode 100644
index 63e75f71..00000000
--- a/api/logic/minecraft/forge/ForgeXzDownload.h
+++ /dev/null
@@ -1,61 +0,0 @@
-/* Copyright 2013-2019 MultiMC Contributors
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#pragma once
-
-#include "net/NetAction.h"
-#include "net/HttpMetaCache.h"
-#include <QFile>
-#include <QTemporaryFile>
-
-typedef std::shared_ptr<class ForgeXzDownload> ForgeXzDownloadPtr;
-
-class ForgeXzDownload : public NetAction
-{
-    Q_OBJECT
-public:
-    MetaEntryPtr m_entry;
-    /// if saving to file, use the one specified in this string
-    QString m_target_path;
-    /// this is the output file, if any
-    QTemporaryFile m_pack200_xz_file;
-    /// path relative to the mirror base
-    QString m_url_path;
-
-public:
-    explicit ForgeXzDownload(QString url, QString relative_path, MetaEntryPtr entry);
-    static ForgeXzDownloadPtr make(QString url, QString relative_path, MetaEntryPtr entry)
-    {
-        return ForgeXzDownloadPtr(new ForgeXzDownload(url, relative_path, entry));
-    }
-    virtual ~ForgeXzDownload(){};
-    bool canAbort() override;
-
-protected
-slots:
-    void downloadProgress(qint64 bytesReceived, qint64 bytesTotal) override;
-    void downloadError(QNetworkReply::NetworkError error) override;
-    void downloadFinished() override;
-    void downloadReadyRead() override;
-
-public
-slots:
-    void start() override;
-    bool abort() override;
-
-private:
-    void decompressAndInstall();
-    void failAndTryNextMirror();
-};
diff --git a/libraries/pack200/CMakeLists.txt b/libraries/pack200/CMakeLists.txt
deleted file mode 100644
index 31eb0f73..00000000
--- a/libraries/pack200/CMakeLists.txt
+++ /dev/null
@@ -1,50 +0,0 @@
-cmake_minimum_required(VERSION 3.1)
-
-project(MultiMC_unpack200)
-
-option(PACK200_BUILD_BINARY "Build a tiny utility that decompresses pack200 streams" OFF)
-
-# Find ZLIB for quazip
-find_package(ZLIB REQUIRED)
-
-set(PACK200_SRC
-    include/unpack200.h
-    src/bands.cpp
-    src/bands.h
-    src/bytes.cpp
-    src/bytes.h
-    src/coding.cpp
-    src/coding.h
-    src/constants.h
-    src/defines.h
-    src/unpack200.cpp
-    src/unpack.cpp
-    src/unpack.h
-    src/utils.cpp
-    src/utils.h
-    src/zip.cpp
-    src/zip.h
-)
-
-if (Qt5_POSITION_INDEPENDENT_CODE)
-    SET(CMAKE_POSITION_INDEPENDENT_CODE ON)
-endif()
-
-add_library(MultiMC_unpack200 SHARED ${PACK200_SRC})
-target_include_directories(MultiMC_unpack200 PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include" "${CMAKE_CURRENT_BINARY_DIR}" PRIVATE ${ZLIB_INCLUDE_DIRS} "${CMAKE_CURRENT_SOURCE_DIR}/src")
-target_link_libraries(MultiMC_unpack200 ${ZLIB_LIBRARIES})
-
-set_target_properties(MultiMC_unpack200 PROPERTIES CXX_VISIBILITY_PRESET hidden VISIBILITY_INLINES_HIDDEN 1)
-generate_export_header(MultiMC_unpack200)
-
-# Install it
-install(
-    TARGETS MultiMC_unpack200
-    RUNTIME DESTINATION ${LIBRARY_DEST_DIR}
-    LIBRARY DESTINATION ${LIBRARY_DEST_DIR}
-)
-
-if(PACK200_BUILD_BINARY)
-    add_executable(anti200 anti200.cpp)
-    target_link_libraries(anti200 MultiMC_unpack200)
-endif()
diff --git a/libraries/pack200/LICENSE b/libraries/pack200/LICENSE
deleted file mode 100644
index b40a0f45..00000000
--- a/libraries/pack200/LICENSE
+++ /dev/null
@@ -1,347 +0,0 @@
-The GNU General Public License (GPL)
-
-Version 2, June 1991
-
-Copyright (C) 1989, 1991 Free Software Foundation, Inc.
-59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-
-Everyone is permitted to copy and distribute verbatim copies of this license
-document, but changing it is not allowed.
-
-Preamble
-
-The licenses for most software are designed to take away your freedom to share
-and change it.  By contrast, the GNU General Public License is intended to
-guarantee your freedom to share and change free software--to make sure the
-software is free for all its users.  This General Public License applies to
-most of the Free Software Foundation's software and to any other program whose
-authors commit to using it.  (Some other Free Software Foundation software is
-covered by the GNU Library General Public License instead.) You can apply it to
-your programs, too.
-
-When we speak of free software, we are referring to freedom, not price.  Our
-General Public Licenses are designed to make sure that you have the freedom to
-distribute copies of free software (and charge for this service if you wish),
-that you receive source code or can get it if you want it, that you can change
-the software or use pieces of it in new free programs; and that you know you
-can do these things.
-
-To protect your rights, we need to make restrictions that forbid anyone to deny
-you these rights or to ask you to surrender the rights.  These restrictions
-translate to certain responsibilities for you if you distribute copies of the
-software, or if you modify it.
-
-For example, if you distribute copies of such a program, whether gratis or for
-a fee, you must give the recipients all the rights that you have.  You must
-make sure that they, too, receive or can get the source code.  And you must
-show them these terms so they know their rights.
-
-We protect your rights with two steps: (1) copyright the software, and (2)
-offer you this license which gives you legal permission to copy, distribute
-and/or modify the software.
-
-Also, for each author's protection and ours, we want to make certain that
-everyone understands that there is no warranty for this free software.  If the
-software is modified by someone else and passed on, we want its recipients to
-know that what they have is not the original, so that any problems introduced
-by others will not reflect on the original authors' reputations.
-
-Finally, any free program is threatened constantly by software patents.  We
-wish to avoid the danger that redistributors of a free program will
-individually obtain patent licenses, in effect making the program proprietary.
-To prevent this, we have made it clear that any patent must be licensed for
-everyone's free use or not licensed at all.
-
-The precise terms and conditions for copying, distribution and modification
-follow.
-
-TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
-
-0. This License applies to any program or other work which contains a notice
-placed by the copyright holder saying it may be distributed under the terms of
-this General Public License.  The "Program", below, refers to any such program
-or work, and a "work based on the Program" means either the Program or any
-derivative work under copyright law: that is to say, a work containing the
-Program or a portion of it, either verbatim or with modifications and/or
-translated into another language.  (Hereinafter, translation is included
-without limitation in the term "modification".) Each licensee is addressed as
-"you".
-
-Activities other than copying, distribution and modification are not covered by
-this License; they are outside its scope.  The act of running the Program is
-not restricted, and the output from the Program is covered only if its contents
-constitute a work based on the Program (independent of having been made by
-running the Program).  Whether that is true depends on what the Program does.
-
-1. You may copy and distribute verbatim copies of the Program's source code as
-you receive it, in any medium, provided that you conspicuously and
-appropriately publish on each copy an appropriate copyright notice and
-disclaimer of warranty; keep intact all the notices that refer to this License
-and to the absence of any warranty; and give any other recipients of the
-Program a copy of this License along with the Program.
-
-You may charge a fee for the physical act of transferring a copy, and you may
-at your option offer warranty protection in exchange for a fee.
-
-2. You may modify your copy or copies of the Program or any portion of it, thus
-forming a work based on the Program, and copy and distribute such modifications
-or work under the terms of Section 1 above, provided that you also meet all of
-these conditions:
-
-    a) You must cause the modified files to carry prominent notices stating
-    that you changed the files and the date of any change.
-
-    b) You must cause any work that you distribute or publish, that in whole or
-    in part contains or is derived from the Program or any part thereof, to be
-    licensed as a whole at no charge to all third parties under the terms of
-    this License.
-
-    c) If the modified program normally reads commands interactively when run,
-    you must cause it, when started running for such interactive use in the
-    most ordinary way, to print or display an announcement including an
-    appropriate copyright notice and a notice that there is no warranty (or
-    else, saying that you provide a warranty) and that users may redistribute
-    the program under these conditions, and telling the user how to view a copy
-    of this License.  (Exception: if the Program itself is interactive but does
-    not normally print such an announcement, your work based on the Program is
-    not required to print an announcement.)
-
-These requirements apply to the modified work as a whole.  If identifiable
-sections of that work are not derived from the Program, and can be reasonably
-considered independent and separate works in themselves, then this License, and
-its terms, do not apply to those sections when you distribute them as separate
-works.  But when you distribute the same sections as part of a whole which is a
-work based on the Program, the distribution of the whole must be on the terms
-of this License, whose permissions for other licensees extend to the entire
-whole, and thus to each and every part regardless of who wrote it.
-
-Thus, it is not the intent of this section to claim rights or contest your
-rights to work written entirely by you; rather, the intent is to exercise the
-right to control the distribution of derivative or collective works based on
-the Program.
-
-In addition, mere aggregation of another work not based on the Pr