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ost::RandomFile Class Reference

The purpose of this class is to define a base class for low level random file access that is portable between Win32 and Posix systems.Portable random disk file access. More...

#include <file.h>

Inheritance diagram for ost::RandomFile:

ost::Mutex ost::File ost::MappedFile ost::SharedFile ost::ThreadFile List of all members.

Public Member Functions

virtual ~RandomFile ()
 Destroy a random access file or it's derived class.
bool initial (void)
 This method should be called right after a RandomFile derived object has been created.
off_t getCapacity (void)
 Get current file capacity.
virtual Error restart (void)
 This method is commonly used to close and re-open an existing database.
Error getErrorNumber (void)
 Return current error id.
char * getErrorString (void)
 Return current error string.
bool operator! (void)

Protected Member Functions

 RandomFile (const char *name=NULL)
 Create an unopened random access file.
 RandomFile (const RandomFile &rf)
 Default copy constructor.
Error error (Error errid, char *errstr=NULL)
 Post an error event.
Error error (char *err)
 Post an extended string error message.
void setError (bool enable)
 Used to enable or disable throwing of exceptions on errors.
Error setCompletion (Complete mode)
 Used to set file completion modes.
void setTemporary (bool enable)
 Used to set the temporary attribute for the file.
virtual Attr initialize (void)
 This method is used to initialize a newly created file as indicated by the "initial" flag.
void final (void)
 Close the file.

Protected Attributes

int fd
Access access
char * pathname
struct {
   unsigned   count: 16
   bool   thrown: 1
   bool   initial: 1
   bool   immediate: 1
   bool   temp: 1
flags

Related Functions

(Note that these are not member functions.)

bool __EXPORT isDir (const char *path)
bool __EXPORT isFile (const char *path)
bool __EXPORT isDevice (const char *path)
bool __EXPORT canAccess (const char *path)
bool __EXPORT canModify (const char *path)
time_t __EXPORT lastModified (const char *path)
time_t __EXPORT lastAccessed (const char *path)

Detailed Description

The purpose of this class is to define a base class for low level random file access that is portable between Win32 and Posix systems.Portable random disk file access.

This class is a foundation both for optimized thread shared and traditional locked file access that is commonly used to build database services, rather than the standard C++ streaming file classes.

Author:
David Sugar <dyfet@ostel.com>


Constructor & Destructor Documentation

ost::RandomFile::RandomFile const char *  name = NULL  )  [protected]
 

Create an unopened random access file.

ost::RandomFile::RandomFile const RandomFile rf  )  [protected]
 

Default copy constructor.

virtual ost::RandomFile::~RandomFile  )  [virtual]
 

Destroy a random access file or it's derived class.


Member Function Documentation

Error ost::RandomFile::error char *  err  )  [inline, protected]
 

Post an extended string error message.

Returns:
errExtended.
Parameters:
errstr error string.

Error ost::RandomFile::error Error  errid,
char *  errstr = NULL
[protected]
 

Post an error event.

Returns:
error code.
Parameters:
errid error code.
errstr error message string.

void ost::RandomFile::final void   )  [protected]
 

Close the file.

off_t ost::RandomFile::getCapacity void   ) 
 

Get current file capacity.

Returns:
total file size.

Error ost::RandomFile::getErrorNumber void   )  [inline]
 

Return current error id.

Returns:
last error identifier set.

char* ost::RandomFile::getErrorString void   )  [inline]
 

Return current error string.

Returns:
last error string set.

bool ost::RandomFile::initial void   ) 
 

This method should be called right after a RandomFile derived object has been created.

This method will invoke initialize if the object is newly created, and set file access permissions appropriately.

Returns:
true if file had to be initialized.

virtual Attr ost::RandomFile::initialize void   )  [protected, virtual]
 

This method is used to initialize a newly created file as indicated by the "initial" flag.

This method also returns the file access permissions that should be associated with the file. This method should never be called directly, but is instead used to impliment the "Initial" method. Typically one would use this to build an empty database shell when a previously empty database file is created.

Returns:
access, or attrInvalid if should be removed.

bool ost::RandomFile::operator! void   ) 
 

virtual Error ost::RandomFile::restart void   )  [virtual]
 

This method is commonly used to close and re-open an existing database.

This may be used when the database has been unlinked and an external process provides a new one to use.

Reimplemented in ost::ThreadFile, and ost::SharedFile.

Error ost::RandomFile::setCompletion Complete  mode  )  [protected]
 

Used to set file completion modes.

Returns:
errSuccess if okay.
Parameters:
mode completion mode.
Todo:
implement in win32

void ost::RandomFile::setError bool  enable  )  [inline, protected]
 

Used to enable or disable throwing of exceptions on errors.

Parameters:
enable true if errors will be thrown.

void ost::RandomFile::setTemporary bool  enable  )  [inline, protected]
 

Used to set the temporary attribute for the file.

Temporary files are automatically deleted when closed.

Parameters:
enable true for marking as temporary.


Friends And Related Function Documentation

bool __EXPORT canAccess const char *  path  )  [related]
 

bool __EXPORT canModify const char *  path  )  [related]
 

bool __EXPORT isDevice const char *  path  )  [related]
 

bool __EXPORT isDir const char *  path  )  [related]
 

bool __EXPORT isFile const char *  path  )  [related]
 

time_t __EXPORT lastAccessed const char *  path  )  [related]
 

time_t __EXPORT lastModified const char *  path  )  [related]
 


Member Data Documentation

Access ost::RandomFile::access [protected]
 

unsigned ost::RandomFile::count [protected]
 

int ost::RandomFile::fd [protected]
 

struct { ... } ost::RandomFile::flags [protected]
 

bool ost::RandomFile::immediate [protected]
 

bool ost::RandomFile::initial [protected]
 

char* ost::RandomFile::pathname [protected]
 

bool ost::RandomFile::temp [protected]
 

bool ost::RandomFile::thrown [protected]
 


The documentation for this class was generated from the following file:
Generated on Fri Jul 22 00:15:51 2005 for GNU CommonC++ by  doxygen 1.4.3-20050530