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

Bayonne2 / Common C++ 2 Framework

MappedFile Class Reference

Create and map a disk file into memory. More...

#include <file.h>

Inheritance diagram for MappedFile:

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Collaboration diagram for MappedFile:

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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

MappedFile (const char *fname, Access mode)

Open a file for mapping. More...

MappedFile (const char *fname, Access mode, size_t size)

Create if not exists, and map a file of specified size into memory. More...

MappedFile (const char *fname, pos_t offset, size_t size, Access mode)

Map a portion or all of a specified file in the specified shared memory access mode. More...

virtual ~MappedFile ()

Release a mapped section of memory associated with a file. More...

void sync (void)

Synchronize the contents of the mapped portion of memory with the disk file and wait for completion. More...

void sync (char *address, size_t len)

Synchronize a segment of memory mapped from a segment fetch. More...

void update (size_t offset=0, size_t len=0)

Map a portion of the memory mapped from the file back to the file and do not wait for completion. More...

void update (char *address, size_t len)

Update a mapped region back to disk as specified by address and length. More...

void release (char *address, size_t len)

Release (unmap) a memory segment. More...

char * fetch (size_t offset=0)

Fetch a pointer to an offset within the memory mapped portion of the disk file. More...

char * fetch (off_t pos, size_t len)

Fetch and map a portion of a disk file to a logical memory block. More...

bool lock (void)

Lock the currently mapped portion of a file. More...

void unlock (void)

Unlock a locked mapped portion of a file. More...

size_t pageAligned (size_t size)

Compute map size to aligned page boundry. More...

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...

virtual Error restart (void)

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

fcb_t fcb

int prot

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

Create and map a disk file into memory.

This portable class works under both Posix via mmap and under the win32 API. A mapped file can be referenced directly by it's memory segment. One can map and unmap portions of a file on demand, and update changed memory pages mapped from files immediately through sync().

Author: David Sugar dyfet.nosp@m.@ost.nosp@m.el.co.nosp@m.m Map a named disk file into memory.

Definition at line 747 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

MappedFile::MappedFile ( const char * fname,

Access mode

)

Open a file for mapping.

More than one segment of a file may be mapped into seperate regions of memory.

Parameters: fname file name to access for mapping.

mode access mode to map file.

MappedFile::MappedFile ( const char * fname,

Access mode,

size_t size

)

Create if not exists, and map a file of specified size into memory.

Parameters: fname file name to access for mapping.

mode access mode to map file.

size of file to map.

MappedFile::MappedFile ( const char * fname,

pos_t offset,

size_t size,

Access mode

)

Map a portion or all of a specified file in the specified shared memory access mode.

Valid mapping modes include mappedRead, mappedWrite, and mappedReadWrite.

Parameters: fname pathname of file to map into memory.

offset from start of file to begin mapping in bytes.

size of mapped area in bytes.

mode to map file.

virtual MappedFile::~MappedFile ( )

virtual

Release a mapped section of memory associated with a file.

The mapped area is updated back to disk.

Member Function Documentation

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.

char* MappedFile::fetch ( size_t offset = 0 )

inline

Fetch a pointer to an offset within the memory mapped portion of the disk file.

This really is used for convience of matching operations between Update and Fetch, as one could simply have accessed the base pointer where the file was mapped directly.

Parameters: offset from start of mapped memory.

Definition at line 846 of file file.h.

char* MappedFile::fetch ( off_t pos,

size_t len

)

Fetch and map a portion of a disk file to a logical memory block.

Returns: pointer to memory segment.

Parameters: pos offset of file segment to map.

len size of memory segment to map.

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

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

bool MappedFile::lock ( void )

Lock the currently mapped portion of a file.

Returns: true if pages are locked.

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.

bool RandomFile::operator! ( void )

inherited

size_t MappedFile::pageAligned ( size_t size )

Compute map size to aligned page boundry.

Parameters: size request.

Returns: page aligned size.

void MappedFile::release ( char * address,

size_t len

)

Release (unmap) a memory segment.

Parameters: address address of memory segment to release.

len length of memory segment to release.

virtual Error RandomFile::restart ( void )

virtualinherited

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 SharedFile, and ThreadFile.

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.

void MappedFile::sync ( void )

Synchronize the contents of the mapped portion of memory with the disk file and wait for completion.

This assures the memory mapped from the file is written back.

void MappedFile::sync ( char * address,

size_t len

)

Synchronize a segment of memory mapped from a segment fetch.

Parameters: address memory address to update.

len size of segment.

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

void MappedFile::unlock ( void )

Unlock a locked mapped portion of a file.

void MappedFile::update ( size_t offset = 0,

size_t len = 0

)

Map a portion of the memory mapped from the file back to the file and do not wait for completion.

This is useful when mapping a database file and updating a single record.

Parameters: offset offset into the mapped region of memory.

len length of partial region (example, record length).

void MappedFile::update ( char * address,

size_t len

)

Update a mapped region back to disk as specified by address and length.

Parameters: address address of segment.

len length of segment.

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 MappedFile::fcb

private

Definition at line 750 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.

int MappedFile::prot

private

Definition at line 751 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