-/////////////////////////////////////////////////////////////////////////////
-// Name: gzstream.cpp
-// Purpose: Streams for Gzip files
-// Author: Mike Wetherell
-// RCS-ID: $Id$
-// Copyright: (c) 2003 Mike Wetherell
-// Licence: wxWindows licence
-/////////////////////////////////////////////////////////////////////////////
-
-#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
-#pragma implementation "gzstream.h"
-#endif
-
-// For compilers that support precompilation, includes "wx.h".
-#include "wx/wxprec.h"
-
-#ifdef __BORLANDC__
- #pragma hdrstop
-#endif
-
-#if wxUSE_STREAMS && wxUSE_GZSTREAM && wxUSE_ZLIB
-
-#include "wx/log.h"
-#include "wx/intl.h"
-#include "wx/datstrm.h"
-#include "wx/txtstrm.h"
-#include "wx/filename.h"
-#include "wx/zstream.h"
-#include "wx/gzstream.h"
-
-#if defined(__WXMSW__) && !defined(__WX_SETUP_H__) && !defined(wxUSE_ZLIB_H_IN_PATH)
- #include "../zlib/zlib.h"
-#else
- #include "zlib.h"
-#endif
-
-
-/////////////////////////////////////////////////////////////////////////////
-// Notes:
-//
-// See RFC-1952 and the Gzip/Zlib sources for the details of the Gzip format
-//
-// Errors are displayed with wxLogError, but not errors from the compressor
-// or underlying stream, since they will display their own errors.
-//
-// Gzip doesn't use flag 2 to indicate a header crc, so I think it's
-// probably better not to use it for the moment.
-//
-
-// Flags
-enum {
- GZ_ASCII_FLAG = 0x01,
- GZ_HEAD_CRC = 0x02,
- GZ_EXTRA_FIELD = 0x04,
- GZ_ORIG_NAME = 0x08,
- GZ_COMMENT = 0x10,
- GZ_RESERVED = 0xE0
-};
-
-// Extra flags
-enum {
- GZ_SLOWEST = 2,
- GZ_FASTEST = 4
-};
-
-const wxUint16 GZ_MAGIC = 0x8b1f;
-
-
-/////////////////////////////////////////////////////////////////////////////
-// Input stream
-
-wxGzipInputStream::wxGzipInputStream(wxInputStream& stream,
- wxMBConv& conv /*=wxConvFile*/)
- : wxFilterInputStream(stream)
-{
- m_decomp = NULL;
- m_crc = crc32(0, Z_NULL, 0);
-
- // Try to read the Gzip magic numbers 0x1f, 0x8b. If not found then the
- // underlying stream isn't gzipped after all, so unread the bytes taken
- // so that the underlying stream can be read directly instead.
- wxUint8 magic[2];
- size_t n = m_parent_i_stream->Read(magic, sizeof(magic)).LastRead();
-
- if (n < sizeof(magic) || ((magic[1] << 8) | magic[0]) != GZ_MAGIC) {
- if (n)
- m_parent_i_stream->Ungetch(magic, n);
- // Set EOF rather than error to indicate no gzip data
- m_lasterror = wxSTREAM_EOF;
- return;
- }
-
- wxDataInputStream ds(*m_parent_i_stream);
-
- // read method, flags, timestamp, extra flags and OS-code
- int method = ds.Read8();
- int flags = ds.Read8();
-#if wxUSE_DATETIME
- wxUint32 datetime = ds.Read32();
- if (datetime) // zero means not set (not -1 as usual for time_t)
- m_datetime = wxLongLong(0, datetime) * 1000L;
-#else
- ds.Read32();
-#endif
- ds.Read8();
- ds.Read8();
-
- if (flags & GZ_HEAD_CRC)
- ds.Read16();
-
- if (flags & GZ_EXTRA_FIELD)
- for (int i = ds.Read16(); i > 0 && m_parent_i_stream->IsOk(); i--)
- m_parent_i_stream->GetC();
-
- // RFC-1952 specifies ISO-8859-1 for these fields
- if (flags & GZ_ORIG_NAME) {
-#if wxUSE_UNICODE
- wxTextInputStream tis(*m_parent_i_stream, wxT(" \t"), conv);
-#else
- wxTextInputStream tis(*m_parent_i_stream);
- (void)conv;
-#endif
- wxChar c;
- while ((c = tis.GetChar()) != 0 && m_parent_i_stream->IsOk())
- m_name += c;
- }
-
- if (flags & GZ_COMMENT)
- while (m_parent_i_stream->GetC() != 0 && m_parent_i_stream->IsOk())
- ; // empty loop
-
- m_lasterror = wxSTREAM_READ_ERROR;
- if (!*m_parent_i_stream) {
- wxLogDebug(wxT("Error reading Gzip header"));
- return;
- }
-
- if (flags & GZ_RESERVED)
- wxLogWarning(_("Unsupported flag in Gzip header"));
-
- switch (method) {
- case Z_DEFLATED:
- m_decomp = new wxZlibInputStream(*m_parent_i_stream, wxZLIB_NO_HEADER);
- break;
-
- default:
- wxLogError(_("unsupported compression method in Gzip stream"));
- return;
- }
-
- if (m_decomp)
- m_lasterror = m_decomp->GetLastError();
-}
-
-
-wxGzipInputStream::~wxGzipInputStream()
-{
- delete m_decomp;
-}
-
-
-size_t wxGzipInputStream::OnSysRead(void *buffer, size_t size)
-{
- wxASSERT_MSG(m_decomp, wxT("Gzip not open"));
-
- if (!m_decomp)
- m_lasterror = wxSTREAM_READ_ERROR;
- if (!IsOk() || !size)
- return 0;
-
- m_decomp->Read(buffer, size);
- m_crc = crc32(m_crc, (Byte*)buffer, m_decomp->LastRead());
-
- if (m_decomp->Eof()) {
- wxDataInputStream ds(*m_parent_i_stream);
- m_lasterror = wxSTREAM_READ_ERROR;
-
- if (m_parent_i_stream->IsOk()) {
- if (ds.Read32() != m_crc)
- wxLogError(_("reading Gzip stream: bad crc"));
- else if (ds.Read32() != (wxUint32)TellI())
- wxLogError(_("reading Gzip stream: incorrect length"));
- else
- m_lasterror = wxSTREAM_EOF;
- }
- }
- else if (!*m_decomp) {
- m_lasterror = wxSTREAM_READ_ERROR;
- }
-
- return m_decomp->LastRead();
-}
-
-
-/////////////////////////////////////////////////////////////////////////////
-// Output stream
-
-wxGzipOutputStream::wxGzipOutputStream(
- wxOutputStream& stream,
- const wxString& originalName /*=wxEmptyString*/,
-#if wxUSE_DATETIME
- const wxDateTime& originalTime /*=wxDateTime::Now()*/,
-#endif
- int level /*=-1*/,
- wxMBConv& conv /*=wxConvFile*/)
- : wxFilterOutputStream(stream)
-{
- m_comp = NULL;
- m_crc = crc32(0, Z_NULL, 0);
-
- wxFileName filename(originalName);
-
- wxUint32 timestamp = 0;
-#if wxUSE_DATETIME
- if (originalTime.IsValid())
- timestamp = (originalTime.GetValue() / 1000L).GetLo();
-#endif
-
- // RFC-1952 specifies ISO-8859-1 for the name. Also it should be just the
- // name part, no directory, folded to lowercase if case insensitive
- wxString name = filename.GetFullName();
- const wxWX2MBbuf mbName = conv.cWX2MB(name);
-
- wxDataOutputStream ds(*m_parent_o_stream);
-
- // write signature, method, flags, timestamp, extra flags and OS-code
- ds.Write16(GZ_MAGIC);
- ds.Write8(Z_DEFLATED);
- ds.Write8(mbName && *mbName ? GZ_ORIG_NAME : 0);
- ds.Write32(timestamp);
- ds.Write8(level == 1 ? GZ_FASTEST : level == 9 ? GZ_SLOWEST : 0);
- ds.Write8(255);
-
- if (mbName && *mbName)
- m_parent_o_stream->Write(mbName, strlen(mbName) + 1);
-
- m_lasterror = wxSTREAM_WRITE_ERROR;
- if (!*m_parent_o_stream) {
- wxLogDebug(wxT("Error writing Gzip header"));
- return;
- }
-
- m_comp = new wxZlibOutputStream(*m_parent_o_stream, level, wxZLIB_NO_HEADER);
-
- if (m_comp)
- m_lasterror = m_comp->GetLastError();
-}
-
-
-wxGzipOutputStream::~wxGzipOutputStream()
-{
- if (m_comp && m_comp->IsOk()) {
- wxUint32 len = (wxUint32)m_comp->TellO();
- delete m_comp;
- if (m_parent_o_stream->IsOk()) {
- wxDataOutputStream ds(*m_parent_o_stream);
- ds.Write32(m_crc);
- ds.Write32(len); // underlying stream will report errors
- }
- } else {
- delete m_comp;
- }
-}
-
-
-void wxGzipOutputStream::Sync()
-{
- wxASSERT_MSG(m_comp, wxT("Gzip not open"));
-
- if (!m_comp)
- m_lasterror = wxSTREAM_WRITE_ERROR;
- if (IsOk())
- m_comp->Sync();
-}
-
-
-size_t wxGzipOutputStream::OnSysWrite(const void *buffer, size_t size)
-{
- wxASSERT_MSG(m_comp, wxT("Gzip not open"));
-
- if (!m_comp)
- m_lasterror = wxSTREAM_WRITE_ERROR;
- if (!IsOk() || !size)
- return 0;
-
- if (m_comp->Write(buffer, size).LastWrite() != size)
- m_lasterror = wxSTREAM_WRITE_ERROR;
- m_crc = crc32(m_crc, (Byte*)buffer, size);
-
- return m_comp->LastWrite();
-}
-
-
-#endif // wxUSE_STREAMS && wxUSE_GZSTREAM && wxUSE_ZLIB