This stream uncompresses all data read from it. It uses the "filtered"
stream to get new compressed data.
+The stream is not seekable, \helpref{SeekI()}{wxinputstreamseeki} returns
+ {\it wxInvalidOffset}. Also \helpref{GetSize()}{wxstreambasegetsize} is
+not supported, it always returns $0$.
+
\wxheading{Derived from}
\helpref{wxFilterInputStream}{wxfilterinputstream}
\wxheading{See also}
-\helpref{wxInputStream}{wxinputstream}
+\helpref{wxInputStream}{wxinputstream},
+ \helpref{wxZlibOutputStream}{wxzliboutputstream}.
+
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxZlibInputStream::wxZlibInputStream}
+
+\func{}{wxZlibInputStream}{\param{wxInputStream\&}{ stream}, \param{int}{ flags = 0}}
+
+{\it flags} should be omitted for normal usage. The flag {\it wxZLIB\_NO_HEADER}
+ is needed when wxZlibInputStream is used as an 'inflate' decompressor for gzip
+or zip files.
+
+{\it wxZLIB\_NO_HEADER} is currently the only flag:
+
+\begin{verbatim}
+// Flags
+enum {
+ wxZLIB_NO_HEADER = 1 // required for use in Gzip and Zip files
+}
+\end{verbatim}
+
% -----------------------------------------------------------------------------
% wxZlibOutputStream
This stream compresses all data written to it, and passes the compressed data
to the "filtered" stream.
+The stream is not seekable, \helpref{SeekO()}{wxoutputstreamseeko} returns
+ {\it wxInvalidOffset}.
+
\wxheading{Derived from}
\helpref{wxFilterOutputStream}{wxfilteroutputstream}
\wxheading{See also}
-\helpref{wxOutputStream}{wxoutputstream}
+\helpref{wxOutputStream}{wxoutputstream},
+ \helpref{wxZlibInputStream}{wxzlibinputstream}
\latexignore{\rtfignore{\wxheading{Members}}}
\membersection{wxZlibOutputStream::wxZlibOutputStream}
-\func{}{wxZlibOutputStream}{\param{wxOutputStream\&}{ stream},\param{int}{ level = -1}}
+\func{}{wxZlibOutputStream}{\param{wxOutputStream\&}{ stream}, \param{int}{ level = -1}, \param{int}{ flags = 0}}
Creates a new write-only compressed stream. {\it level} means level of
compression. It is number between 0 and 9 (including these values) where
0 means no compression and 9 best but slowest compression. -1 is default
value (currently equivalent to 6).
+
+{\it flags} should be omitted for normal usage. The flag {\it wxZLIB\_NO_HEADER}
+ suppresses the generation of the zlib header and checksum, and is required
+when wxZlibOutputStream is used as a 'deflate' compressor for gzip or zip files.
+
+The following symbols can be use for the compression level and flags:
+
+\begin{verbatim}
+// Compression level
+enum {
+ wxZ_DEFAULT_COMPRESSION = -1,
+ wxZ_NO_COMPRESSION = 0,
+ wxZ_BEST_SPEED = 1,
+ wxZ_BEST_COMPRESSION = 9
+}
+
+// Flags
+enum {
+ wxZLIB_NO_HEADER = 1 // required for use in Gzip and Zip files
+}
+\end{verbatim}
+
// Name: zstream.h
// Purpose: Memory stream classes
// Author: Guilhem Lavaux
-// Modified by:
+// Modified by: Mike Wetherell
// Created: 11/07/98
// RCS-ID: $Id$
// Copyright: (c) Guilhem Lavaux
#include "wx/stream.h"
+// Compression level
+enum {
+ wxZ_DEFAULT_COMPRESSION = -1,
+ wxZ_NO_COMPRESSION = 0,
+ wxZ_BEST_SPEED = 1,
+ wxZ_BEST_COMPRESSION = 9
+};
+
+// Flags
+enum {
+ wxZLIB_NO_HEADER = 1 // required for use in Gzip and Zip files
+};
+
class WXDLLIMPEXP_BASE wxZlibInputStream: public wxFilterInputStream {
public:
- wxZlibInputStream(wxInputStream& stream);
+ wxZlibInputStream(wxInputStream& stream, int flags = 0);
virtual ~wxZlibInputStream();
+ char Peek() { return wxInputStream::Peek(); }
+ size_t GetSize() const { return wxInputStream::GetSize(); }
+
protected:
size_t OnSysRead(void *buffer, size_t size);
+ off_t OnSysTell() const { return m_pos; }
protected:
size_t m_z_size;
unsigned char *m_z_buffer;
struct z_stream_s *m_inflate;
+ off_t m_pos;
DECLARE_NO_COPY_CLASS(wxZlibInputStream)
};
class WXDLLIMPEXP_BASE wxZlibOutputStream: public wxFilterOutputStream {
public:
- wxZlibOutputStream(wxOutputStream& stream, int level = -1);
+ wxZlibOutputStream(wxOutputStream& stream, int level = -1, int flags = 0);
virtual ~wxZlibOutputStream();
- void Sync();
+ void Sync() { DoFlush(false); }
+ size_t GetSize() const { return (size_t)m_pos; }
protected:
size_t OnSysWrite(const void *buffer, size_t size);
+ off_t OnSysTell() const { return m_pos; }
+
+ virtual void DoFlush(bool final);
protected:
size_t m_z_size;
unsigned char *m_z_buffer;
struct z_stream_s *m_deflate;
+ off_t m_pos;
DECLARE_NO_COPY_CLASS(wxZlibOutputStream)
};
-/////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////
// Name: zstream.cpp
// Purpose: Compressed stream classes
// Author: Guilhem Lavaux
-// Modified by:
+// Modified by: Mike Wetherell
// Created: 11/07/98
// RCS-ID: $Id$
// Copyright: (c) Guilhem Lavaux
#include "zlib.h"
#endif
-#define ZSTREAM_BUFFER_SIZE 1024
+enum {
+#ifdef __WIN16__
+ ZSTREAM_BUFFER_SIZE = 4096
+#else
+ ZSTREAM_BUFFER_SIZE = 16384
+#endif
+};
//////////////////////
// wxZlibInputStream
//////////////////////
-wxZlibInputStream::wxZlibInputStream(wxInputStream& stream)
+wxZlibInputStream::wxZlibInputStream(wxInputStream& stream, int flags)
: wxFilterInputStream(stream)
{
- // I need a private stream buffer.
- m_inflate = new z_stream_s;
+ m_inflate = NULL;
+ m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
+ m_z_size = ZSTREAM_BUFFER_SIZE;
+ m_pos = 0;
- m_inflate->zalloc = (alloc_func)0;
- m_inflate->zfree = (free_func)0;
- m_inflate->opaque = (voidpf)0;
+ if (m_z_buffer) {
+ m_inflate = new z_stream_s;
- int err = inflateInit(m_inflate);
- if (err != Z_OK) {
- inflateEnd(m_inflate);
- delete m_inflate;
- return;
- }
+ if (m_inflate) {
+ m_inflate->zalloc = (alloc_func)0;
+ m_inflate->zfree = (free_func)0;
+ m_inflate->opaque = (voidpf)0;
+ m_inflate->avail_in = 0;
+ m_inflate->next_in = NULL;
+ m_inflate->next_out = NULL;
- m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
- m_z_size = ZSTREAM_BUFFER_SIZE;
+ int bits = (flags & wxZLIB_NO_HEADER) ? -MAX_WBITS : MAX_WBITS;
- m_inflate->avail_in = 0;
- m_inflate->next_in = NULL;
+ if (inflateInit2(m_inflate, bits) == Z_OK)
+ return;
+ }
+ }
+
+ wxLogError(_("Can't initialize zlib inflate stream."));
+ m_lasterror = wxSTREAM_READ_ERROR;
}
wxZlibInputStream::~wxZlibInputStream()
size_t wxZlibInputStream::OnSysRead(void *buffer, size_t size)
{
- int err;
+ wxASSERT_MSG(m_inflate && m_z_buffer, wxT("Inflate stream not open"));
+
+ if (!m_inflate || !m_z_buffer)
+ m_lasterror = wxSTREAM_READ_ERROR;
+ if (!IsOk() || !size)
+ return 0;
+ int err = Z_OK;
m_inflate->next_out = (unsigned char *)buffer;
m_inflate->avail_out = size;
- while (m_inflate->avail_out > 0) {
+ while (err == Z_OK && m_inflate->avail_out > 0) {
if (m_inflate->avail_in == 0) {
-
- m_parent_i_stream->Read(m_z_buffer, wxMin(m_z_size, size));
+ m_parent_i_stream->Read(m_z_buffer, m_z_size);
m_inflate->next_in = m_z_buffer;
m_inflate->avail_in = m_parent_i_stream->LastRead();
- wxStreamError err = m_parent_i_stream->GetLastError();
- if ( err != wxSTREAM_NO_ERROR && err != wxSTREAM_EOF)
- {
- m_lasterror = err;
- return 0; // failed to read anything
+ if (m_inflate->avail_in == 0) {
+ if (m_parent_i_stream->Eof())
+ wxLogError(_("Can't read inflate stream: unexpected EOF in underlying stream."));
+ m_lasterror = wxSTREAM_READ_ERROR;
+ break;
}
+ }
+ err = inflate(m_inflate, Z_NO_FLUSH);
+ }
- if ( m_inflate->avail_in == 0 )
- {
- // EOF
- m_lasterror = wxSTREAM_EOF;
- break;
- }
+ if (err == Z_STREAM_END) {
+ // Unread any data taken from past the end of the deflate stream, so that
+ // any additional data can be read from the underlying stream (the crc
+ // in a gzip for example)
+ if (m_inflate->avail_in) {
+ m_parent_i_stream->Ungetch(m_inflate->next_in, m_inflate->avail_in);
+ m_inflate->avail_in = 0;
}
- err = inflate(m_inflate, Z_FINISH);
- if (err == Z_STREAM_END)
- return (size - m_inflate->avail_out);
+ m_lasterror = wxSTREAM_EOF;
+ } else if (err != Z_OK) {
+ wxLogError(_("Can't read from inflate stream (zlib error %d)."), err);
+ m_lasterror = wxSTREAM_READ_ERROR;
}
- return size-m_inflate->avail_out;
+ size -= m_inflate->avail_out;
+ m_pos += size;
+ return size;
}
//////////////////////
// wxZlibOutputStream
//////////////////////
-wxZlibOutputStream::wxZlibOutputStream(wxOutputStream& stream, int level)
+wxZlibOutputStream::wxZlibOutputStream(wxOutputStream& stream,
+ int level,
+ int flags)
: wxFilterOutputStream(stream)
{
- int err;
-
- m_deflate = new z_stream_s;
-
- m_deflate->zalloc = (alloc_func)0;
- m_deflate->zfree = (free_func)0;
- m_deflate->opaque = (voidpf)0;
+ m_deflate = NULL;
+ m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
+ m_z_size = ZSTREAM_BUFFER_SIZE;
+ m_pos = 0;
if ( level == -1 )
{
- level = Z_DEFAULT_COMPRESSION;
+ level = Z_DEFAULT_COMPRESSION;
}
else
{
wxASSERT_MSG(level >= 0 && level <= 9, wxT("wxZlibOutputStream compression level must be between 0 and 9!"));
}
- err = deflateInit(m_deflate, level);
- if (err != Z_OK) {
- deflateEnd(m_deflate);
- return;
- }
+ if (m_z_buffer) {
+ m_deflate = new z_stream_s;
- m_z_buffer = new unsigned char[ZSTREAM_BUFFER_SIZE];
- m_z_size = ZSTREAM_BUFFER_SIZE;
+ if (m_deflate) {
+ m_deflate->zalloc = (alloc_func)0;
+ m_deflate->zfree = (free_func)0;
+ m_deflate->opaque = (voidpf)0;
+ m_deflate->avail_in = 0;
+ m_deflate->next_out = m_z_buffer;
+ m_deflate->avail_out = m_z_size;
+
+ int bits = (flags & wxZLIB_NO_HEADER) ? -MAX_WBITS : MAX_WBITS;
- m_deflate->avail_in = 0;
- m_deflate->next_out = m_z_buffer;
- m_deflate->avail_out = m_z_size;
+ if (deflateInit2(m_deflate, level, Z_DEFLATED, bits,
+ 8, Z_DEFAULT_STRATEGY) == Z_OK)
+ return;
+ }
+ }
+
+ wxLogError(_("Can't initialize zlib deflate stream."));
+ m_lasterror = wxSTREAM_WRITE_ERROR;
}
wxZlibOutputStream::~wxZlibOutputStream()
{
- int err;
-
- Sync();
-
- err = deflate(m_deflate, Z_FINISH);
- if (err != Z_STREAM_END)
- {
- wxLogDebug( wxT("wxZlibOutputStream: an error occured while closing the stream.\n") );
- return;
- }
-
+ if (m_deflate && m_z_buffer)
+ DoFlush(true);
deflateEnd(m_deflate);
delete m_deflate;
delete[] m_z_buffer;
}
-void wxZlibOutputStream::Sync()
+void wxZlibOutputStream::DoFlush(bool final)
{
- int err;
-
- m_parent_o_stream->Write(m_z_buffer, m_z_size-m_deflate->avail_out);
- m_deflate->next_out = m_z_buffer;
- m_deflate->avail_out = m_z_size;
+ wxASSERT_MSG(m_deflate && m_z_buffer, wxT("Deflate stream not open"));
- err = deflate(m_deflate, Z_FULL_FLUSH);
- if (err != Z_OK) {
+ if (!m_deflate || !m_z_buffer)
+ m_lasterror = wxSTREAM_WRITE_ERROR;
+ if (!IsOk())
return;
- }
- // Fixed by "Stefan Csomor" <csomor@advancedconcepts.ch>
- while( m_deflate->avail_out == 0 )
- {
- m_parent_o_stream->Write(m_z_buffer, m_z_size );
- m_deflate->next_out = m_z_buffer;
- m_deflate->avail_out = m_z_size;
- err = deflate(m_deflate, Z_FULL_FLUSH);
- if (err != Z_OK) {
- return;
- }
- }
- // End
+ int err = Z_OK;
+ bool done = false;
- m_parent_o_stream->Write(m_z_buffer, m_z_size-m_deflate->avail_out);
- m_deflate->next_out = m_z_buffer;
- m_deflate->avail_out = m_z_size;
+ while (err == Z_OK || err == Z_STREAM_END) {
+ size_t len = m_z_size - m_deflate->avail_out;
+ if (len) {
+ if (m_parent_o_stream->Write(m_z_buffer, len).LastWrite() != len) {
+ m_lasterror = wxSTREAM_WRITE_ERROR;
+ wxLogDebug(wxT("wxZlibOutputStream: Error writing to underlying stream"));
+ break;
+ }
+ m_deflate->next_out = m_z_buffer;
+ m_deflate->avail_out = m_z_size;
+ }
+
+ if (done)
+ break;
+ err = deflate(m_deflate, final ? Z_FINISH : Z_FULL_FLUSH);
+ done = m_deflate->avail_out != 0 || err == Z_STREAM_END;
+ }
}
size_t wxZlibOutputStream::OnSysWrite(const void *buffer, size_t size)
{
- int err;
+ wxASSERT_MSG(m_deflate && m_z_buffer, wxT("Deflate stream not open"));
+ if (!m_deflate || !m_z_buffer)
+ m_lasterror = wxSTREAM_WRITE_ERROR;
+ if (!IsOk() || !size)
+ return 0;
+
+ int err = Z_OK;
m_deflate->next_in = (unsigned char *)buffer;
m_deflate->avail_in = size;
- while (m_deflate->avail_in > 0) {
-
+ while (err == Z_OK && m_deflate->avail_in > 0) {
if (m_deflate->avail_out == 0) {
m_parent_o_stream->Write(m_z_buffer, m_z_size);
- if ( !*m_parent_o_stream )
- return (size - m_deflate->avail_in);
+ if (m_parent_o_stream->LastWrite() != m_z_size) {
+ m_lasterror = wxSTREAM_WRITE_ERROR;
+ wxLogDebug(wxT("wxZlibOutputStream: Error writing to underlying stream"));
+ break;
+ }
m_deflate->next_out = m_z_buffer;
m_deflate->avail_out = m_z_size;
}
err = deflate(m_deflate, Z_NO_FLUSH);
- if (err != Z_OK)
- return (size - m_deflate->avail_in);
}
+
+ if (err != Z_OK) {
+ m_lasterror = wxSTREAM_WRITE_ERROR;
+ wxLogError(_("Can't write to deflate stream (zlib error %d)."), err);
+ }
+
+ size -= m_deflate->avail_in;
+ m_pos += size;
return size;
}
projects / wxWidgets.git / commitdiff
