sfile.h
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- /*
- * sfile.h
- *
- * Structured file I/O channel class.
- *
- * Portable Windows Library
- *
- * Copyright (c) 1993-1998 Equivalence Pty. Ltd.
- *
- * The contents of this file are subject to the Mozilla Public License
- * Version 1.0 (the "License"); you may not use this file except in
- * compliance with the License. You may obtain a copy of the License at
- * http://www.mozilla.org/MPL/
- *
- * Software distributed under the License is distributed on an "AS IS"
- * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
- * the License for the specific language governing rights and limitations
- * under the License.
- *
- * The Original Code is Portable Windows Library.
- *
- * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
- *
- * Portions are Copyright (C) 1993 Free Software Foundation, Inc.
- * All Rights Reserved.
- *
- * Contributor(s): ______________________________________.
- *
- * $Log: sfile.h,v $
- * Revision 1.15 1999/03/09 02:59:51 robertj
- * Changed comments to doc++ compatible documentation.
- *
- * Revision 1.14 1999/02/16 08:11:10 robertj
- * MSVC 6.0 compatibility changes.
- *
- * Revision 1.13 1998/09/24 07:24:01 robertj
- * Moved structured fiel into separate module so don't need silly implementation file for GNU C.
- *
- * Revision 1.12 1998/09/23 06:21:23 robertj
- * Added open source copyright license.
- *
- * Revision 1.11 1996/01/23 13:15:38 robertj
- * Mac Metrowerks compiler support.
- *
- * Revision 1.10 1995/06/17 11:13:19 robertj
- * Documentation update.
- *
- * Revision 1.9 1995/03/14 12:42:34 robertj
- * Updated documentation to use HTML codes.
- *
- * Revision 1.8 1995/01/14 06:19:39 robertj
- * Documentation
- *
- * Revision 1.7 1994/08/23 11:32:52 robertj
- * Oops
- *
- * Revision 1.6 1994/08/22 00:46:48 robertj
- * Added pragma fro GNU C++ compiler.
- *
- * Revision 1.5 1994/04/20 12:17:44 robertj
- * PFilePath split
- *
- * Revision 1.4 1994/01/03 04:42:23 robertj
- * Mass changes to common container classes and interactors etc etc etc.
- *
- * Revision 1.3 1993/08/21 01:50:33 robertj
- * Made Clone() function optional, default will assert if called.
- *
- * Revision 1.2 1993/07/14 12:49:16 robertj
- * Fixed RCS keywords.
- *
- */
- #define _PSTRUCTUREDFILE
- #ifdef __GNUC__
- #pragma interface
- #endif
- /**A class representing a a structured file that is portable accross CPU
- architectures (as in the XDR protocol).
-
- This differs from object serialisation in that the access is always to a
- disk file and is random access. It would primarily be used for database
- type applications.
- */
- class PStructuredFile : public PFile
- {
- PCLASSINFO(PStructuredFile, PFile);
- private:
- BOOL Read(void * buf, PINDEX len) { return PFile::Read(buf, len); }
- BOOL Write(const void * buf, PINDEX len) { return PFile::Write(buf, len); }
- public:
- /**@name Construction */
- //@{
- /**Create a structured file object but do not open it. It does not
- initially have a valid file name. However, an attempt to open the file
- using the #PFile::Open()# function will generate a unique
- temporary file.
-
- The initial structure size is one byte.
- */
- PStructuredFile();
- /**Create a unique temporary file name, and open the file in the specified
- mode and using the specified options. Note that opening a new, unique,
- temporary file name in ReadOnly mode will always fail. This would only
- be usefull in a mode and options that will create the file.
- The #PChannel::IsOpen()# function may be used after object
- construction to determine if the file was successfully opened.
- */
- PStructuredFile(
- OpenMode mode, /// Mode in which to open the file.
- int opts = ModeDefault /// #OpenOptions enum# for open operation.
- );
-
- /**Create a structured file object with the specified name and open it in
- the specified mode and with the specified options.
- The #PChannel::IsOpen()# function may be used after object
- construction to determine if the file was successfully opened.
- */
- PStructuredFile(
- const PFilePath & name, /// Name of file to open.
- OpenMode mode = ReadWrite, /// Mode in which to open the file.
- int opts = ModeDefault /// #OpenOptions enum# for open operation.
- );
- //@}
- /**@name Structured I/O functions */
- //@{
- /**Read a sequence of bytes into the specified buffer, translating the
- structure according to the specification made in the
- #SetStructure()# function.
- @return
- TRUE if the structure was successfully read.
- */
- BOOL Read(
- void * buffer /// Pointer to structure to receive data.
- );
-
- /**Write a sequence of bytes into the specified buffer, translating the
- structure according to the specification made in the
- #SetStructure()# function.
- @return
- TRUE if the structure was successfully written.
- */
- BOOL Write(
- const void * buffer /// Pointer to structure to write data from.
- );
- //@}
- /**@name Structure definition functions */
- //@{
- /**Get the size of each structure in the file.
- @return
- number of bytes in a structure.
- */
- PINDEX GetStructureSize() { return structureSize; }
- /// All element types in a structure
- enum ElementType {
- /// Element is a single character.
- Character,
- /// Element is a 16 bit integer.
- Integer16,
- /// Element is a 32 bit integer.
- Integer32,
- /// Element is a 64 bit integer.
- Integer64,
- /// Element is a 32 bit IEE floating point number.
- Float32,
- /// Element is a 64 bit IEE floating point number.
- Float64,
- /// Element is a 80 bit IEE floating point number.
- Float80,
- NumElementTypes
- };
- /// Elements in the structure definition.
- struct Element {
- /// Type of element in structure.
- ElementType type;
- /// Count of elements of this type.
- PINDEX count;
- };
- /** Set the structure of each record in the file. */
- void SetStructure(
- Element * structure, /// Array of structure elements
- PINDEX numElements /// Number of structure elements in structure.
- );
- //@}
- protected:
- // Member variables
- /// Number of bytes in structure.
- PINDEX structureSize;
- /// Array of elements in the structure.
- Element * structure;
- /// Number of elements in the array.
- PINDEX numElements;
- #ifdef DOC_PLUS_PLUS
- };
- #endif
- // Class declaration continued in platform specific header file ///////////////