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Diffstat (limited to 'kioslave/gzip/kgzipfilter.cpp')
| -rw-r--r-- | kioslave/gzip/kgzipfilter.cpp | 336 |
1 files changed, 336 insertions, 0 deletions
diff --git a/kioslave/gzip/kgzipfilter.cpp b/kioslave/gzip/kgzipfilter.cpp new file mode 100644 index 000000000..21380c6c1 --- /dev/null +++ b/kioslave/gzip/kgzipfilter.cpp @@ -0,0 +1,336 @@ +/* This file is part of the KDE libraries + Copyright (C) 2000 David Faure <faure@kde.org> + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License version 2 as published by the Free Software Foundation. + + This library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public License + along with this library; see the file COPYING.LIB. If not, write to + the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301, USA. +*/ + +#include "kgzipfilter.h" +#include <time.h> +#include <zlib.h> +#include <kdebug.h> +#include <klibloader.h> + +/* gzip flag byte */ +#define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ +#define HEAD_CRC 0x02 /* bit 1 set: header CRC present */ +#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ +#define ORIG_NAME 0x08 /* bit 3 set: original file name present */ +#define COMMENT 0x10 /* bit 4 set: file comment present */ +#define RESERVED 0xE0 /* bits 5..7: reserved */ + + +// #define DEBUG_GZIP + +class KGzipFilterFactory : public KLibFactory +{ +public: + KGzipFilterFactory() : KLibFactory() {} + ~KGzipFilterFactory(){} + QObject *createObject( QObject *parent, const char *name, const char*className, const QStringList & args ) + { + Q_UNUSED(parent); + Q_UNUSED(name); + Q_UNUSED(className); + Q_UNUSED(args); + return new KGzipFilter; + } +}; + +K_EXPORT_COMPONENT_FACTORY( kgzipfilter, KGzipFilterFactory ) + +// Not really necessary anymore, now that this is a dynamically-loaded lib. +class KGzipFilter::KGzipFilterPrivate +{ +public: + z_stream zStream; + bool bCompressed; +}; + +KGzipFilter::KGzipFilter() +{ + d = new KGzipFilterPrivate; + d->zStream.zalloc = (alloc_func)0; + d->zStream.zfree = (free_func)0; + d->zStream.opaque = (voidpf)0; +} + + +KGzipFilter::~KGzipFilter() +{ + delete d; +} + +void KGzipFilter::init( int mode ) +{ + d->zStream.next_in = Z_NULL; + d->zStream.avail_in = 0; + if ( mode == IO_ReadOnly ) + { + int result = inflateInit2(&d->zStream, -MAX_WBITS); // windowBits is passed < 0 to suppress zlib header + if ( result != Z_OK ) + kdDebug(7005) << "inflateInit returned " << result << endl; + // No idea what to do with result :) + } else if ( mode == IO_WriteOnly ) + { + int result = deflateInit2(&d->zStream, Z_DEFAULT_COMPRESSION, Z_DEFLATED, -MAX_WBITS, 8, Z_DEFAULT_STRATEGY); // same here + if ( result != Z_OK ) + kdDebug(7005) << "deflateInit returned " << result << endl; + } else { + kdWarning(7005) << "KGzipFilter: Unsupported mode " << mode << ". Only IO_ReadOnly and IO_WriteOnly supported" << endl; + } + m_mode = mode; + d->bCompressed = true; + m_headerWritten = false; +} + +void KGzipFilter::terminate() +{ + if ( m_mode == IO_ReadOnly ) + { + int result = inflateEnd(&d->zStream); + if ( result != Z_OK ) + kdDebug(7005) << "inflateEnd returned " << result << endl; + } else if ( m_mode == IO_WriteOnly ) + { + int result = deflateEnd(&d->zStream); + if ( result != Z_OK ) + kdDebug(7005) << "deflateEnd returned " << result << endl; + } +} + + +void KGzipFilter::reset() +{ + if ( m_mode == IO_ReadOnly ) + { + int result = inflateReset(&d->zStream); + if ( result != Z_OK ) + kdDebug(7005) << "inflateReset returned " << result << endl; + } else if ( m_mode == IO_WriteOnly ) { + int result = deflateReset(&d->zStream); + if ( result != Z_OK ) + kdDebug(7005) << "deflateReset returned " << result << endl; + m_headerWritten = false; + } +} + +bool KGzipFilter::readHeader() +{ +#ifdef DEBUG_GZIP + kdDebug(7005) << "KGzipFilter::readHeader avail=" << d->zStream.avail_in << endl; +#endif + // Assume not compressed until we successfully decode the header + d->bCompressed = false; + // Assume the first block of data contains the whole header. + // The right way is to build this as a big state machine which + // is a pain in the ass. + // With 8K-blocks, we don't risk much anyway. + Bytef *p = d->zStream.next_in; + int i = d->zStream.avail_in; + if ((i -= 10) < 0) return false; // Need at least 10 bytes +#ifdef DEBUG_GZIP + kdDebug(7005) << "KGzipFilter::readHeader first byte is " << QString::number(*p,16) << endl; +#endif + if (*p++ != 0x1f) return false; // GZip magic +#ifdef DEBUG_GZIP + kdDebug(7005) << "KGzipFilter::readHeader second byte is " << QString::number(*p,16) << endl; +#endif + if (*p++ != 0x8b) return false; + int method = *p++; + int flags = *p++; + if ((method != Z_DEFLATED) || (flags & RESERVED) != 0) return false; + p += 6; + if ((flags & EXTRA_FIELD) != 0) // skip extra field + { + if ((i -= 2) < 0) return false; // Need at least 2 bytes + int len = *p++; + len += (*p++) << 8; + if ((i -= len) < 0) return false; // Need at least len bytes + p += len; + } + if ((flags & ORIG_NAME) != 0) // skip original file name + { +#ifdef DEBUG_GZIP + kdDebug(7005) << "ORIG_NAME=" << p << endl; +#endif + while( (i > 0) && (*p)) + { + i--; p++; + } + if (--i <= 0) return false; + p++; + } + if ((flags & COMMENT) != 0) // skip comment + { + while( (i > 0) && (*p)) + { + i--; p++; + } + if (--i <= 0) return false; + p++; + } + if ((flags & HEAD_CRC) != 0) // skip the header crc + { + if ((i-=2) < 0) return false; + p += 2; + } + + d->zStream.avail_in = i; + d->zStream.next_in = p; + d->bCompressed = true; +#ifdef DEBUG_GZIP + kdDebug(7005) << "header OK" << endl; +#endif + return true; +} + +/* Output a 16 bit value, lsb first */ +#define put_short(w) \ + *p++ = (uchar) ((w) & 0xff); \ + *p++ = (uchar) ((ushort)(w) >> 8); + +/* Output a 32 bit value to the bit stream, lsb first */ +#define put_long(n) \ + put_short((n) & 0xffff); \ + put_short(((ulong)(n)) >> 16); + +bool KGzipFilter::writeHeader( const QCString & fileName ) +{ + Bytef *p = d->zStream.next_out; + int i = d->zStream.avail_out; + *p++ = 0x1f; + *p++ = 0x8b; + *p++ = Z_DEFLATED; + *p++ = ORIG_NAME; + put_long( time( 0L ) ); // Modification time (in unix format) + *p++ = 0; // Extra flags (2=max compress, 4=fastest compress) + *p++ = 3; // Unix + + uint len = fileName.length(); + for ( uint j = 0 ; j < len ; ++j ) + *p++ = fileName[j]; + *p++ = 0; + int headerSize = p - d->zStream.next_out; + i -= headerSize; + Q_ASSERT(i>0); + m_crc = crc32(0L, Z_NULL, 0); + d->zStream.next_out = p; + d->zStream.avail_out = i; + m_headerWritten = true; + return true; +} + +void KGzipFilter::writeFooter() +{ + Q_ASSERT( m_headerWritten ); + if (!m_headerWritten) kdDebug() << kdBacktrace(); + Bytef *p = d->zStream.next_out; + int i = d->zStream.avail_out; + //kdDebug(7005) << "KGzipFilter::writeFooter writing CRC= " << QString::number( m_crc, 16 ) << endl; + put_long( m_crc ); + //kdDebug(7005) << "KGzipFilter::writing writing totalin= " << d->zStream.total_in << endl; + put_long( d->zStream.total_in ); + i -= p - d->zStream.next_out; + d->zStream.next_out = p; + d->zStream.avail_out = i; +} + +void KGzipFilter::setOutBuffer( char * data, uint maxlen ) +{ + d->zStream.avail_out = maxlen; + d->zStream.next_out = (Bytef *) data; +} +void KGzipFilter::setInBuffer( const char * data, uint size ) +{ +#ifdef DEBUG_GZIP + kdDebug(7005) << "KGzipFilter::setInBuffer avail_in=" << size << endl; +#endif + d->zStream.avail_in = size; + d->zStream.next_in = (Bytef*) data; +} +int KGzipFilter::inBufferAvailable() const +{ + return d->zStream.avail_in; +} +int KGzipFilter::outBufferAvailable() const +{ + return d->zStream.avail_out; +} + +KGzipFilter::Result KGzipFilter::uncompress_noop() +{ + // I'm not sure we really need support for that (uncompressed streams), + // but why not, it can't hurt to have it. One case I can think of is someone + // naming a tar file "blah.tar.gz" :-) + if ( d->zStream.avail_in > 0 ) + { + int n = (d->zStream.avail_in < d->zStream.avail_out) ? d->zStream.avail_in : d->zStream.avail_out; + memcpy( d->zStream.next_out, d->zStream.next_in, n ); + d->zStream.avail_out -= n; + d->zStream.next_in += n; + d->zStream.avail_in -= n; + return OK; + } else + return END; +} + +KGzipFilter::Result KGzipFilter::uncompress() +{ + Q_ASSERT ( m_mode == IO_ReadOnly ); + if ( d->bCompressed ) + { +#ifdef DEBUG_GZIP + kdDebug(7005) << "Calling inflate with avail_in=" << inBufferAvailable() << " avail_out=" << outBufferAvailable() << endl; + kdDebug(7005) << " next_in=" << d->zStream.next_in << endl; +#endif + int result = inflate(&d->zStream, Z_SYNC_FLUSH); +#ifdef DEBUG_GZIP + kdDebug(7005) << " -> inflate returned " << result << endl; + kdDebug(7005) << "Now avail_in=" << inBufferAvailable() << " avail_out=" << outBufferAvailable() << endl; + kdDebug(7005) << " next_in=" << d->zStream.next_in << endl; +#else + if ( result != Z_OK && result != Z_STREAM_END ) + kdDebug(7005) << "Warning: inflate() returned " << result << endl; +#endif + return ( result == Z_OK ? OK : ( result == Z_STREAM_END ? END : ERROR ) ); + } else + return uncompress_noop(); +} + +KGzipFilter::Result KGzipFilter::compress( bool finish ) +{ + Q_ASSERT ( d->bCompressed ); + Q_ASSERT ( m_mode == IO_WriteOnly ); + + Bytef* p = d->zStream.next_in; + ulong len = d->zStream.avail_in; +#ifdef DEBUG_GZIP + kdDebug(7005) << " calling deflate with avail_in=" << inBufferAvailable() << " avail_out=" << outBufferAvailable() << endl; +#endif + int result = deflate(&d->zStream, finish ? Z_FINISH : Z_NO_FLUSH); + if ( result != Z_OK && result != Z_STREAM_END ) + kdDebug(7005) << " deflate returned " << result << endl; + if ( m_headerWritten ) + { + //kdDebug(7005) << "Computing CRC for the next " << len - d->zStream.avail_in << " bytes" << endl; + m_crc = crc32(m_crc, p, len - d->zStream.avail_in); + } + if ( result == Z_STREAM_END && m_headerWritten ) + { + //kdDebug(7005) << "KGzipFilter::compress finished, write footer" << endl; + writeFooter(); + } + return ( result == Z_OK ? OK : ( result == Z_STREAM_END ? END : ERROR ) ); +} |