///////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
// Digital Ltd. LLC
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Industrial Light & Magic nor the names of
// its contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
///////////////////////////////////////////////////////////////////////////
#ifndef INCLUDED_IMF_IO_H
#define INCLUDED_IMF_IO_H
//-----------------------------------------------------------------------------
//
// Low-level file input and output for OpenEXR.
//
//-----------------------------------------------------------------------------
#include <ImfInt64.h>
#include <string>
namespace Imf {
//-----------------------------------------------------------
// class IStream -- an abstract base class for input streams.
//-----------------------------------------------------------
class IStream
{
public:
//-----------
// Destructor
//-----------
virtual ~IStream ();
//-------------------------------------------------
// Does this input stream support memory-mapped IO?
//
// Memory-mapped streams can avoid an extra copy;
// memory-mapped read operations return a pointer
// to an internal buffer instead of copying data
// into a buffer supplied by the caller.
//-------------------------------------------------
virtual bool isMemoryMapped () const;
//------------------------------------------------------
// Read from the stream:
//
// read(c,n) reads n bytes from the stream, and stores
// them in array c. If the stream contains less than n
// bytes, or if an I/O error occurs, read(c,n) throws
// an exception. If read(c,n) reads the last byte from
// the file it returns false, otherwise it returns true.
//------------------------------------------------------
virtual bool read (char c[/*n*/], int n) = 0;
//---------------------------------------------------
// Read from a memory-mapped stream:
//
// readMemoryMapped(n) reads n bytes from the stream
// and returns a pointer to the first byte. The
// returned pointer remains valid until the stream
// is closed. If there are less than n byte left to
// read in the stream or if the stream is not memory-
// mapped, readMemoryMapped(n) throws an exception.
//---------------------------------------------------
virtual char * readMemoryMapped (int n);
//--------------------------------------------------------
// Get the current reading position, in bytes from the
// beginning of the file. If the next call to read() will
// read the first byte in the file, tellg() returns 0.
//--------------------------------------------------------
virtual Int64 tellg () = 0;
//-------------------------------------------
// Set the current reading position.
// After calling seekg(i), tellg() returns i.
//-------------------------------------------
virtual void seekg (Int64 pos) = 0;
//------------------------------------------------------
// Clear error conditions after an operation has failed.
//------------------------------------------------------
virtual void clear ();
//------------------------------------------------------
// Get the name of the file associated with this stream.
//------------------------------------------------------
const char * fileName () const;
protected:
IStream (const char fileName[]);
private:
IStream (const IStream &); // not implemented
IStream & operator = (const IStream &); // not implemented
std::string _fileName;
};
//-----------------------------------------------------------
// class OStream -- an abstract base class for output streams
//-----------------------------------------------------------
class OStream
{
public:
//-----------
// Destructor
//-----------
virtual ~OStream ();
//----------------------------------------------------------
// Write to the stream:
//
// write(c,n) takes n bytes from array c, and stores them
// in the stream. If an I/O error occurs, write(c,n) throws
// an exception.
//----------------------------------------------------------
virtual void write (const char c[/*n*/], int n) = 0;
//---------------------------------------------------------
// Get the current writing position, in bytes from the
// beginning of the file. If the next call to write() will
// start writing at the beginning of the file, tellp()
// returns 0.
//---------------------------------------------------------
virtual Int64 tellp () = 0;
//-------------------------------------------
// Set the current writing position.
// After calling seekp(i), tellp() returns i.
//-------------------------------------------
virtual void seekp (Int64 pos) = 0;
//------------------------------------------------------
// Get the name of the file associated with this stream.
//------------------------------------------------------
const char * fileName () const;
protected:
OStream (const char fileName[]);
private:
OStream (const OStream &); // not implemented
OStream & operator = (const OStream &); // not implemented
std::string _fileName;
};
//-----------------------
// Helper classes for Xdr
//-----------------------
struct StreamIO
{
static void
writeChars (OStream &os, const char c[/*n*/], int n)
{
os.write (c, n);
}
static bool
readChars (IStream &is, char c[/*n*/], int n)
{
return is.read (c, n);
}
};
struct CharPtrIO
{
static void
writeChars (char *&op, const char c[/*n*/], int n)
{
while (n--)
*op++ = *c++;
}
static bool
readChars (const char *&ip, char c[/*n*/], int n)
{
while (n--)
*c++ = *ip++;
return true;
}
};
} // namespace Imf
#endif