Bayonne2 / Common C++ 2 Framework: SharedFile Class Reference

Bayonne2 / Common C++ 2 Framework

SharedFile Class Reference

This class defines a database I/O file service that can be shared by multiple processes. More...

#include <file.h>

Inheritance diagram for SharedFile:

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Collaboration diagram for SharedFile:

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Public Types

enum Error {
  errSuccess = 0, errNotOpened, errMapFailed, errInitFailed,
  errOpenDenied, errOpenFailed, errOpenInUse, errReadInterrupted,
  errReadIncomplete, errReadFailure, errWriteInterrupted, errWriteIncomplete,
  errWriteFailure, errLockFailure, errExtended
}

typedef enum Error Error

enum Access { accessReadOnly = O_RDONLY, accessWriteOnly = O_WRONLY, accessReadWrite = O_RDWR }

typedef enum Access Access

enum Open {
openReadOnly = O_RDONLY, openWriteOnly = O_WRONLY, openReadWrite = O_RDWR, openAppend = O_WRONLY | O_APPEND,
openSync = O_RDWR, openTruncate = O_RDWR | O_TRUNC
}

typedef enum Open Open

enum Attr { attrInvalid = 0, attrPrivate = 0400 | 0200, attrGroup = attrPrivate | 0040 | 0020, attrPublic = attrGroup | 0004 | 0002 }

typedef enum Attr Attr

enum Mapping { mappedRead = accessReadOnly, mappedWrite = accessWriteOnly, mappedReadWrite = accessReadWrite }

typedef enum Mapping Mapping

enum Complete { completionImmediate, completionDelayed, completionDeferred }

typedef enum Complete Complete

Public Member Functions

SharedFile (const char *path)

Open or create a new database file. More...

SharedFile (const SharedFile &file)

Create a shared file as a duplicate of an existing shared file. More...

virtual ~SharedFile ()

Close and finish a database file. More...

Error restart (void)

Restart an existing database; close and re-open. More...

Error fetch (char *address=NULL, ccxx_size_t length=0, off_t position=-1)

Lock and Fetch a portion of the file into physical memory. More...

Error update (char *address=NULL, ccxx_size_t length=0, off_t position=-1)

Update a portion of a file from physical memory. More...

Error clear (ccxx_size_t length=0, off_t pos=-1)

Clear a lock held from a previous fetch operation without updating. More...

Error append (char *address=NULL, ccxx_size_t length=0)

Add new data to the end of the file. More...

off_t getPosition (void)

Fetch the current file position marker for this thread. More...

bool operator++ (void)

bool operator-- (void)

bool initial (void)

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

off_t getCapacity (void)

Get current file capacity. More...

Error getErrorNumber (void)

Return current error id. More...

char * getErrorString (void)

Return current error string. More...

bool operator! (void)

Static Public Member Functions

static const char * getExtension (const char *path)

static const char * getFilename (const char *path)

static char * getFilename (const char *path, char *buffer, size_t size=64)

static char * getDirname (const char *path, char *buffer, size_t size=256)

static char * getRealpath (const char *path, char *buffer, size_t size=256)

Protected Types

typedef struct File::_fcb fcb_t

Protected Member Functions

Error error (Error errid, char *errstr=NULL)

Post an error event. More...

Error error (char *err)

Post an extended string error message. More...

void setError (bool enable)

Used to enable or disable throwing of exceptions on errors. More...

Error setCompletion (Complete mode)

Used to set file completion modes. More...

void setTemporary (bool enable)

Used to set the temporary attribute for the file. More...

virtual Attr initialize (void)

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

void final (void)

Close the file. More...

void nameMutex (const char *name)

Enable setting of mutex name for deadlock debug. More...

void enterMutex (void)

Entering a Mutex locks the mutex for the current thread. More...

void enter (void)

Future abi will use enter/leave/test members. More...

void leave (void)

Future abi will use enter/leave/test members. More...

bool test (void)

Future abi will use enter/leave/test members. More...

bool tryEnterMutex (void)

Tries to lock the mutex for the current thread. More...

void leaveMutex (void)

Leaving a mutex frees that mutex for use by another thread. More...

Static Protected Member Functions

static void setDebug (bool mode)

Enable or disable deadlock debugging. More...

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

Private Member Functions

Error open (const char *path)

Private Attributes

fcb_t fcb

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

This class defines a database I/O file service that can be shared by multiple processes.

Each thread should access a dup of the database object, and mutex locks can be used to preserve transaction integrety if multiple threads are used.

SharedFile is used when a database may be shared between multiple processes. SharedFile automatically applies low level byte-range "file locks", and provides an interface to fetch and release byte-range locked portions of a file.

Author: David Sugar dyfet.nosp@m.@ost.nosp@m.el.co.nosp@m.m This class defines a database I/O file service that can be shared by multiple processes.

Definition at line 648 of file file.h.

Member Typedef Documentation

typedef enum Access File::Access

inherited

Definition at line 150 of file file.h.

typedef enum Attr File::Attr

inherited

Definition at line 213 of file file.h.

typedef enum Complete File::Complete

inherited

Definition at line 239 of file file.h.

typedef enum Error File::Error

inherited

Definition at line 137 of file file.h.

typedef struct File::_fcb File::fcb_t

protectedinherited

typedef enum Mapping File::Mapping

inherited

Definition at line 240 of file file.h.

typedef enum Open File::Open

inherited

Definition at line 183 of file file.h.

Member Enumeration Documentation

enum File::Access

inherited

Enumerator
accessReadOnly
accessWriteOnly
accessReadWrite

Definition at line 139 of file file.h.

enum File::Attr

inherited

Enumerator
attrInvalid
attrPrivate
attrGroup
attrPublic

Definition at line 199 of file file.h.

enum File::Complete

inherited

Enumerator
completionImmediate
completionDelayed
completionDeferred

Definition at line 233 of file file.h.

enum File::Error

inherited

Enumerator
errSuccess
errNotOpened
errMapFailed
errInitFailed
errOpenDenied
errOpenFailed
errOpenInUse
errReadInterrupted
errReadIncomplete
errReadFailure
errWriteInterrupted
errWriteIncomplete
errWriteFailure
errLockFailure
errExtended

Definition at line 120 of file file.h.

enum File::Mapping

inherited

Enumerator
mappedRead
mappedWrite
mappedReadWrite

Definition at line 228 of file file.h.

enum File::Open

inherited

Enumerator
openReadOnly
openWriteOnly
openReadWrite
openAppend
openSync
openTruncate

Definition at line 171 of file file.h.

Constructor & Destructor Documentation

SharedFile::SharedFile ( const char * path )

Open or create a new database file.

You should also use Initial.

Parameters: path pathname of database to open.

SharedFile::SharedFile ( const SharedFile & file )

Create a shared file as a duplicate of an existing shared file.

Parameters: file original file.

virtual SharedFile::~SharedFile ( )

virtual

Close and finish a database file.

Member Function Documentation

Error SharedFile::append ( char * address = NULL,

ccxx_size_t length = 0

)

Add new data to the end of the file.

Locks file during append.

Parameters: address address to use, or NULL if same as last I/O.

length length to use, or 0 if same as last I/O.

Error SharedFile::clear ( ccxx_size_t length = 0,

off_t pos = -1

)

Clear a lock held from a previous fetch operation without updating.

Returns: errSuccess on success.

Parameters: length length to use, or 0 if same as last I/O.

pos file position to use or -1 if same as last I/O.

void Mutex::enter ( void )

inlineinherited

Future abi will use enter/leave/test members.

Definition at line 263 of file thread.h.

void Mutex::enterMutex ( void )

inherited

Entering a Mutex locks the mutex for the current thread.

This also can be done using the ENTER_CRITICAL macro or by using the ++ operator on a mutex.

See Also: leaveMutex

Error RandomFile::error ( Error errid,

char * errstr = NULL

)

protectedinherited

Post an error event.

Returns: error code.

Parameters: errid error code.

errstr error message string.

Error RandomFile::error ( char * err )

inlineprotectedinherited

Post an extended string error message.

Returns: errExtended.

Parameters: err error string.

Definition at line 447 of file file.h.

Error SharedFile::fetch ( char * address = NULL,

ccxx_size_t length = 0,

off_t position = -1

)

Lock and Fetch a portion of the file into physical memory.

This can use state information to fetch the current record multiple times.

Returns: errSuccess on success.

Parameters: address address to use, or NULL if same as last I/O.

length length to use, or 0 if same as last I/O.

position file position to use -1 if same as last I/O.

void RandomFile::final ( void )

protectedinherited

Close the file.

off_t RandomFile::getCapacity ( void )

inherited

Get current file capacity.

Returns: total file size.

static char* File::getDirname ( const char * path,

char * buffer,

size_t size = 256

)

staticinherited

Error RandomFile::getErrorNumber ( void )

inlineinherited

Return current error id.

Returns: last error identifier set.

Definition at line 532 of file file.h.

char* RandomFile::getErrorString ( void )

inlineinherited

Return current error string.

Returns: last error string set.

Definition at line 540 of file file.h.

static const char* File::getExtension ( const char * path )

staticinherited

static const char* File::getFilename ( const char * path )

staticinherited

static char* File::getFilename ( const char * path,

char * buffer,

size_t size = 64

)

staticinherited

off_t SharedFile::getPosition ( void )

Fetch the current file position marker for this thread.

Returns: file position offset.

static char* File::getRealpath ( const char * path,

char * buffer,

size_t size = 256

)

staticinherited

bool RandomFile::initial ( void )

inherited

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 RandomFile::initialize ( void )

protectedvirtualinherited

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.

void Mutex::leave ( void )

inlineinherited

Future abi will use enter/leave/test members.

Definition at line 269 of file thread.h.

void Mutex::leaveMutex ( void )

inherited

Leaving a mutex frees that mutex for use by another thread.

If the mutex has been entered (invoked) multiple times (recursivily) by the same thread, then it will need to be exited the same number of instances before it is free for re-use. This operation can also be done using the LEAVE_CRITICAL macro or by the – operator on a mutex.

See Also: enterMutex

void Mutex::nameMutex ( const char * name )

inlineinherited

Enable setting of mutex name for deadlock debug.

Parameters: name for mutex.

Definition at line 248 of file thread.h.

Error SharedFile::open ( const char * path )

private

bool RandomFile::operator! ( void )

inherited

bool SharedFile::operator++ ( void )

bool SharedFile::operator-- ( void )

Error SharedFile::restart ( void )

inlinevirtual

Restart an existing database; close and re-open.

Returns: errSuccess if successful.

Reimplemented from RandomFile.

Definition at line 681 of file file.h.

Error RandomFile::setCompletion ( Complete mode )

protectedinherited

Used to set file completion modes.

Returns: errSuccess if okay.

Parameters: mode completion mode.

Todo:: implement in win32

static void Mutex::setDebug ( bool mode )

inlinestaticinherited

Enable or disable deadlock debugging.

Parameters: mode debug mode.

Definition at line 240 of file thread.h.

void RandomFile::setError ( bool enable )

inlineprotectedinherited

Used to enable or disable throwing of exceptions on errors.

Parameters: enable true if errors will be thrown.

Definition at line 456 of file file.h.

void RandomFile::setTemporary ( bool enable )

inlineprotectedinherited

Used to set the temporary attribute for the file.

Temporary files are automatically deleted when closed.

Parameters: enable true for marking as temporary.

Definition at line 476 of file file.h.

bool Mutex::test ( void )

inlineinherited

Future abi will use enter/leave/test members.

Returns: true if entered.

Definition at line 277 of file thread.h.

bool Mutex::tryEnterMutex ( void )

inherited

Tries to lock the mutex for the current thread.

Behaves like enterMutex , except that it doesn't block the calling thread if the mutex is already locked by another thread.

Returns: true if locking the mutex was succesful otherwise false

See Also: enterMutex; leaveMutex

Error SharedFile::update ( char * address = NULL,

ccxx_size_t length = 0,

off_t position = -1

)

Update a portion of a file from physical memory.

This can use state information to commit the last read record. The current lock is also cleared.

Returns: errSuccess on success.

Parameters: address address to use, or NULL if same as last I/O.

length length to use, or 0 if same as last I/O.

position file position to use or -1 if same as last I/O.

Friends And Related Function Documentation

bool __EXPORT canAccess ( const char * path )

bool __EXPORT canModify ( const char * path )

bool __EXPORT isDevice ( const char * path )

bool __EXPORT isDir ( const char * path )

bool __EXPORT isFile ( const char * path )

time_t __EXPORT lastAccessed ( const char * path )

time_t __EXPORT lastModified ( const char * path )

Field Documentation

Access RandomFile::access

protectedinherited

Definition at line 406 of file file.h.

unsigned RandomFile::count

inherited

Definition at line 413 of file file.h.

fcb_t SharedFile::fcb

private

Definition at line 651 of file file.h.

int RandomFile::fd

protectedinherited

Definition at line 404 of file file.h.

struct { ... } RandomFile::flags

bool RandomFile::immediate

inherited

Definition at line 417 of file file.h.

bool RandomFile::initial

inherited

Definition at line 415 of file file.h.

char* RandomFile::pathname

protectedinherited

Definition at line 410 of file file.h.

bool RandomFile::temp

inherited

Definition at line 419 of file file.h.

bool RandomFile::thrown

inherited

Definition at line 414 of file file.h.

The documentation for this class was generated from the following file:

file.h

Generated on Dec 21, 2017 for commoncpp2-1.8.1, ccrtp-1.7.2, libzrtpcpp-2.3.4, ccscript3-1.1.7, ccaudio2-1.0.0 and bayonne2-2.3.2 (after installation in /usr/local/) by doxygen 1.8.6