diff options
Diffstat (limited to 'kviewshell/plugins/djvu/libdjvu/ByteStream.h')
| -rw-r--r-- | kviewshell/plugins/djvu/libdjvu/ByteStream.h | 416 |
1 files changed, 416 insertions, 0 deletions
diff --git a/kviewshell/plugins/djvu/libdjvu/ByteStream.h b/kviewshell/plugins/djvu/libdjvu/ByteStream.h new file mode 100644 index 00000000..7ecfd8b7 --- /dev/null +++ b/kviewshell/plugins/djvu/libdjvu/ByteStream.h @@ -0,0 +1,416 @@ +//C- -*- C++ -*- +//C- ------------------------------------------------------------------- +//C- DjVuLibre-3.5 +//C- Copyright (c) 2002 Leon Bottou and Yann Le Cun. +//C- Copyright (c) 2001 AT&T +//C- +//C- This software is subject to, and may be distributed under, the +//C- GNU General Public License, Version 2. The license should have +//C- accompanied the software or you may obtain a copy of the license +//C- from the Free Software Foundation at http://www.fsf.org . +//C- +//C- This program is distributed in the hope that it will be useful, +//C- but WITHOUT ANY WARRANTY; without even the implied warranty of +//C- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +//C- GNU General Public License for more details. +//C- +//C- DjVuLibre-3.5 is derived from the DjVu(r) Reference Library +//C- distributed by Lizardtech Software. On July 19th 2002, Lizardtech +//C- Software authorized us to replace the original DjVu(r) Reference +//C- Library notice by the following text (see doc/lizard2002.djvu): +//C- +//C- ------------------------------------------------------------------ +//C- | DjVu (r) Reference Library (v. 3.5) +//C- | Copyright (c) 1999-2001 LizardTech, Inc. All Rights Reserved. +//C- | The DjVu Reference Library is protected by U.S. Pat. No. +//C- | 6,058,214 and patents pending. +//C- | +//C- | This software is subject to, and may be distributed under, the +//C- | GNU General Public License, Version 2. The license should have +//C- | accompanied the software or you may obtain a copy of the license +//C- | from the Free Software Foundation at http://www.fsf.org . +//C- | +//C- | The computer code originally released by LizardTech under this +//C- | license and unmodified by other parties is deemed "the LIZARDTECH +//C- | ORIGINAL CODE." Subject to any third party intellectual property +//C- | claims, LizardTech grants recipient a worldwide, royalty-free, +//C- | non-exclusive license to make, use, sell, or otherwise dispose of +//C- | the LIZARDTECH ORIGINAL CODE or of programs derived from the +//C- | LIZARDTECH ORIGINAL CODE in compliance with the terms of the GNU +//C- | General Public License. This grant only confers the right to +//C- | infringe patent claims underlying the LIZARDTECH ORIGINAL CODE to +//C- | the extent such infringement is reasonably necessary to enable +//C- | recipient to make, have made, practice, sell, or otherwise dispose +//C- | of the LIZARDTECH ORIGINAL CODE (or portions thereof) and not to +//C- | any greater extent that may be necessary to utilize further +//C- | modifications or combinations. +//C- | +//C- | The LIZARDTECH ORIGINAL CODE is provided "AS IS" WITHOUT WARRANTY +//C- | OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED +//C- | TO ANY WARRANTY OF NON-INFRINGEMENT, OR ANY IMPLIED WARRANTY OF +//C- | MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. +//C- +------------------------------------------------------------------ +// +// $Id: ByteStream.h,v 1.11 2003/11/07 22:08:20 leonb Exp $ +// $Name: release_3_5_15 $ + +#ifndef _BYTESTREAM_H +#define _BYTESTREAM_H +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif +#if NEED_GNUG_PRAGMAS +# pragma interface +#endif + +/** @name ByteStream.h + + Files #"ByteStream.h"# and #"ByteStream.cpp"# define input/output classes + similar in spirit to the well known C++ #iostream# classes. Class + \Ref{ByteStream} is an abstract base class for all byte streams. It + defines a virtual interface and also provides useful functions. These + files provide two subclasses. Class \Ref{ByteStream::Stdio} provides a + simple interface to the Ansi C buffered input/output functions. Class + \Ref{ByteStream::Memory} provides stream-like access to a dynamical array + maintained in memory. Class \Ref{ByteStream::Static} provides read-only + stream-like access to a user allocated data buffer. + + {\bf Notes} --- These classes were partly written because we did not want to + depend on the standard C++ library. The main reason however is related to + the browser interface. We want to have a tight control over the + implementation of subclasses because we want to use a byte stream to + represent data passed by a web browser to a plugin. This operation + involves multi-threading issues that many implementations of the standard + C++ library would squarely ignore. + + @memo + Input/output classes + @author + L\'eon Bottou <leonb@research.att.com> -- initial implementation\\ + Andrei Erofeev <eaf@geocities.com> -- + +// From: Leon Bottou, 1/31/2002 +// This file has very little to do with my initial implementation. +// It has been practically rewritten by Lizardtech for i18n changes. +// Our original implementation consisted of multiple classes. +// <http://prdownloads.sourceforge.net/djvu/DjVu2_2b-src.tgz>. + + + @version + #$Id: ByteStream.h,v 1.11 2003/11/07 22:08:20 leonb Exp $# */ +//@{ + + +#include "Arrays.h" +#include <stdio.h> + +#ifdef HAVE_NAMESPACES +namespace DJVU { +# ifdef NOT_DEFINED // Just to fool emacs c++ mode +} +#endif +#endif + +class GURL; +class GUTF8String; +class GNativeString; + +/** Abstract class for a stream of bytes. Class #ByteStream# represent an + object from which (resp. to which) bytes can be read (resp. written) as + with a regular file. Virtual functions #read# and #write# must implement + these two basic operations. In addition, function #tell# returns an + offset identifying the current position, and function #seek# may be used + to change the current position. + + {\bf Note}. Both the copy constructor and the copy operator are declared + as private members. It is therefore not possible to make multiple copies + of instances of this class, as implied by the class semantic. +*/ +class ByteStream : public GPEnabled +{ +public: + class Stdio; + class Static; + class Memory; + class Wrapper; + enum codepage_type {RAW,AUTO,NATIVE,UTF8} cp; + + /** @name Virtual Functions. + These functions are usually implemented by each subclass of #ByteStream#. + */ + //@{ +public: + /** Virtual destructor. */ + virtual ~ByteStream(); + /** Reads data from a ByteStream. This function {\em must} be implemented + by each subclass of #ByteStream#. At most #size# bytes are read from + the ByteStream and stored in the memory area pointed to by #buffer#. + Function #read# returns immediately if #size# is zero. The actual number + of bytes read is returned. Function #read# returns a number of bytes + smaller than #size# if the end-of-file mark is reached before filling + the buffer. Subsequent invocations will always return value #0#. + Function #read# may also return a value greater than zero but smaller + than #size# for internal reasons. Programs must be ready to handle these + cases or use function \Ref{readall}. Exception \Ref{GException} is + thrown with a plain text error message whenever an error occurs. */ + virtual size_t read(void *buffer, size_t size); + /** Writes data to a ByteStream. This function {\em must} be implemented by + each subclass of #ByteStream#. At most #size# bytes from buffer + #buffer# are written to the ByteStream. Function #write# returns + immediately if #size# is zero. The actual number of bytes written is + returned. Function #write# may also return a value greater than zero but + smaller than #size# for internal reasons. Programs must be ready to + handle these cases or use function \Ref{writall}. Exception + \Ref{GException} is thrown with a plain text error message whenever an + error occurs. */ + virtual size_t write(const void *buffer, size_t size); + /** Returns the offset of the current position in the ByteStream. This + function {\em must} be implemented by each subclass of #ByteStream#. */ + virtual long tell(void) const = 0; + /** Sets the current position for reading or writing the ByteStream. Class + #ByteStream# provides a default implementation able to seek forward by + calling function #read# until reaching the desired position. Subclasses + implementing better seek capabilities must override this default + implementation. The new current position is computed by applying + displacement #offset# to the position represented by argument + #whence#. The following values are recognized for argument #whence#: + \begin{description} + \item[#SEEK_SET#] Argument #offset# indicates the position relative to + the beginning of the ByteStream. + \item[#SEEK_CUR#] Argument #offset# is a signed displacement relative to + the current position. + \item[#SEEK_END#] Argument #offset# is a displacement relative to the end + of the file. It is then advisable to provide a negative value for #offset#. + \end{description} + Results are undefined whenever the new position is greater than the + total size of the ByteStream. + + {\bf Error reporting}: + If #seek()# succeeds, #0# is returned. Otherwise it either returns + #-1# (if #nothrow# is set to #FALSE#) or throws the \Ref{GException} + exception. */ + virtual int seek(long offset, int whence = SEEK_SET, bool nothrow=false); + /** Flushes all buffers in the ByteStream. Calling this function + guarantees that pending data have been actually written (i.e. passed to + the operating system). Class #ByteStream# provides a default + implementation which does nothing. */ + virtual void flush(void); + //@} + /** @name Utility Functions. + Class #ByteStream# implements these functions using the virtual + interface functions only. All subclasses of #ByteStream# inherit these + functions. */ + //@{ +public: + /** Reads data and blocks until everything has been read. This function is + essentially similar to function #read#. Unlike function #read# however, + function #readall# will never return a value smaller than #size# unless + an end-of-file mark is reached. This is implemented by repeatedly + calling function #read# until everything is read or until we reach an + end-of-file mark. Note that #read# and #readall# are equivalent when + #size# is one. */ + size_t readall(void *buffer, size_t size); + /** Writes data and blocks until everything has been written. This function + is essentially similar to function #write#. Unlike function #write# + however, function #writall# will only return after all #size# bytes have + been written. This is implemented by repeatedly calling function + #write# until everything is written. Note that #write# and #writall# + are equivalent when #size# is one. */ + size_t writall(const void *buffer, size_t size); + /** Copy data from another ByteStream. A maximum of #size# bytes are read + from the ByteStream #bsfrom# and are written to the ByteStream #*this# + at the current position. Less than #size# bytes may be written if an + end-of-file mark is reached on #bsfrom#. This function returns the + total number of bytes copied. Setting argument #size# to zero (the + default value) has a special meaning: the copying process will continue + until reaching the end-of-file mark on ByteStream #bsfrom#, regardless + of the number of bytes transferred. */ + size_t copy(ByteStream &bsfrom, size_t size=0); + /** Create a new #ByteStream# that copies the data from this #ByteStream# + starting from the current position, upto #size# bytes. Setting the + #size# to zero means copy to the end-of-file mark. */ + GP<ByteStream> duplicate(const size_t size=0) const; + /// Allows printf() type operations to a bytestream. + size_t format(const char *fmt, ... ); + /// Allows scanf() type operations on a bytestream. + int scanf(const char *fmt, ... ); + /** Writes the string as is, to the specified stream. */ + size_t writestring(const GUTF8String &s); + /** Writes the string as is, to the specified stream. */ + size_t writestring(const GNativeString &s); + /** Formats the message string, looks up the external representation + and writes it to the specified stream. */ + void formatmessage( const char *fmt, ... ); + /** Looks up the message and writes it to the specified stream. */ + void writemessage( const char *message ); + /** Writes a one-byte integer to a ByteStream. */ + void write8 (unsigned int card8); + /** Writes a two-bytes integer to a ByteStream. + The integer most significant byte is written first, + regardless of the processor endianness. */ + void write16(unsigned int card16); + /** Writes a three-bytes integer to a ByteStream. + The integer most significant byte is written first, + regardless of the processor endianness. */ + void write24(unsigned int card24); + /** Writes a four-bytes integer to a ByteStream. + The integer most significant bytes are written first, + regardless of the processor endianness. */ + void write32(unsigned int card32); + /** Reads a one-byte integer from a ByteStream. */ + unsigned int read8 (); + /** Reads a two-bytes integer from a ByteStream. + The integer most significant byte is read first, + regardless of the processor endianness. */ + unsigned int read16(); + /** Reads a three-bytes integer from a ByteStream. + The integer most significant byte is read first, + regardless of the processor endianness. */ + unsigned int read24(); + /** Reads a four-bytes integer from a ByteStream. + The integer most significant bytes are read first, + regardless of the processor endianness. */ + unsigned int read32(); + /** Returns the total number of bytes contained in the buffer, file, etc. + Valid offsets for function #seek# range from 0 to the value returned + by this function. */ + virtual int size(void) const; + /// Use at your own risk, only guarenteed to work for ByteStream::Memorys. + TArray<char> get_data(void); + /** Reads data from a random position. This function reads at most #sz# + bytes at position #pos# into #buffer# and returns the actual number of + bytes read. The current position is unchanged. */ + virtual size_t readat(void *buffer, size_t sz, int pos); + /// Returns false, unless a subclass of ByteStream::Static + virtual bool is_static(void) const { return false; } + //@} +protected: + ByteStream(void) : cp(AUTO) {}; +private: + // Cancel C++ default stuff + ByteStream(const ByteStream &); + ByteStream & operator=(const ByteStream &); +public: + /** Constructs an empty Memory ByteStream. The buffer itself is organized + as an array of 4096 byte blocks. The buffer is initially empty. You + must first use function #write# to store data into the buffer, use + function #seek# to rewind the current position, and function #read# to + read the data back. */ + static GP<ByteStream> create(void); + /** Constructs a Memory ByteStream by copying initial data. The + Memory buffer is initialized with #size# bytes copied from the + memory area pointed to by #buffer#. */ + static GP<ByteStream> create(void const * const buffer, const size_t size); + /** Constructs a ByteStream for accessing the file named #url#. + Arguments #url# and #mode# are similar to the arguments of the well + known stdio function #fopen#. In addition a url of #-# will be + interpreted as the standard output or the standard input according to + #mode#. This constructor will open a stdio file and construct a + ByteStream object accessing this file. Destroying the ByteStream object + will flush and close the associated stdio file. Exception + \Ref{GException} is thrown with a plain text error message if the stdio + file cannot be opened. */ + static GP<ByteStream> create( + const GURL &url, char const * const mode); + /** Same as the above, but uses stdin or stdout */ + static GP<ByteStream> create( char const * const mode); + + /** Constructs a ByteStream for accessing the stdio file #f#. + Argument #mode# indicates the type of the stdio file, as in the + well known stdio function #fopen#. Destroying the ByteStream + object will not close the stdio file #f# unless closeme is true. */ + static GP<ByteStream> create( + const int fd, char const * const mode, const bool closeme); + + /** Constructs a ByteStream for accessing the stdio file #f#. + Argument #mode# indicates the type of the stdio file, as in the + well known stdio function #fopen#. Destroying the ByteStream + object will not close the stdio file #f# unless closeme is true. */ + static GP<ByteStream> create( + FILE * const f, char const * const mode, const bool closeme); + /** Creates a ByteStream object for allocating the memory area of + length #sz# starting at address #buffer#. This call impliments + a read-only ByteStream interface for a memory area specified by + the user at construction time. Calls to function #read# directly + access this memory area. The user must therefore make sure that its + content remain valid long enough. */ + static GP<ByteStream> create_static( + void const * const buffer, const size_t size); + + /** Easy access to preallocated stdin/stdout/stderr bytestreams */ + static GP<ByteStream> get_stdin(char const * const mode=0); + static GP<ByteStream> get_stdout(char const * const mode=0); + static GP<ByteStream> get_stderr(char const * const mode=0); + + /** This is the conventional name for EOF exceptions */ + static const char *EndOfFile; + /** Returns the contents of the file as a GNativeString */ + GNativeString getAsNative(void); + /** Returns the contents of the file as a GUTF8String */ + GUTF8String getAsUTF8(void); +}; + +inline size_t +ByteStream::readat(void *buffer, size_t sz, int pos) +{ + size_t retval; + long tpos=tell(); + seek(pos, SEEK_SET, true); + retval=readall(buffer,sz); + seek(tpos, SEEK_SET, true); + return retval; +} + +inline int +ByteStream::size(void) const +{ + ByteStream *bs=const_cast<ByteStream *>(this); + int bsize=(-1); + long pos=tell(); + if(bs->seek(0,SEEK_END,true)) + { + bsize=(int)tell(); + (void)(bs->seek(pos,SEEK_SET,false)); + } + return bsize; +} + +/** ByteStream::Wrapper implements wrapping bytestream. This is useful + for derived classes that take a GP<ByteStream> as a creation argument, + and the backwards compatible bytestreams. */ +class ByteStream::Wrapper : public ByteStream +{ +protected: + GP<ByteStream> gbs; + ByteStream *bs; + Wrapper(void) : bs(0) {} + Wrapper(const GP<ByteStream> &xbs) : gbs(xbs), bs(xbs) {} +public: + ~Wrapper(); + ByteStream * operator & () const {return bs;} + ByteStream * operator & () {return bs;} + virtual size_t read(void *buffer, size_t size) + { return bs->read(buffer,size); } + virtual size_t write(const void *buffer, size_t size) + { return bs->write(buffer,size); } + virtual long tell(void) const + { return bs->tell(); } + virtual int seek(long offset, int whence = SEEK_SET, bool nothrow=false) + { return bs->seek(offset,whence,nothrow); } + virtual void flush(void) + { bs->flush(); } +}; + + +//@} + +// ------------ THE END + +#ifdef HAVE_NAMESPACES +} +# ifndef NOT_USING_DJVU_NAMESPACE +using namespace DJVU; +# endif +#endif +#endif + |