WvStreams
Public Member Functions | Static Public Member Functions | Protected Attributes | List of all members
WvMagicCircle Class Reference

A circular queue that can be accessed across fork(). More...

#include <wvmagiccircle.h>

Inheritance diagram for WvMagicCircle:
Inheritance graph
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Public Member Functions

 WvMagicCircle (size_t size)
 Creates a shared memory circular queue. More...
 
size_t used ()
 
size_t left ()
 
size_t put (const void *data, size_t len)
 
size_t get (void *data, size_t len)
 
size_t skip (size_t len)
 
const char * wstype () const
 
virtual bool isok () const
 By default, returns true if geterr() == 0. More...
 
virtual int geterr () const
 If isok() is false, return the system error number corresponding to the error, -1 for a special error string (which you can obtain with errstr()) or 0 on end of file. More...
 
virtual WvString errstr () const
 
virtual void seterr (int _errnum)
 Set the errnum variable – we have an error. More...
 
void seterr (WvStringParm specialerr)
 
void seterr (WVSTRING_FORMAT_DECL)
 
void seterr (const WvErrorBase &err)
 
void seterr_both (int _errnum, WvStringParm specialerr)
 
void seterr_both (int _errnum, WVSTRING_FORMAT_DECL)
 
void noerr ()
 Reset our error state - there's no error condition anymore.
 

Static Public Member Functions

static WvString strerror (int errnum)
 A replacement for the operating system ::strerror() function that can map more kinds of error strings (especially in win32).
 

Protected Attributes

WvShmZone shm
 
volatile int & head
 
volatile int & tail
 
int size
 
char * circle
 
int errnum
 
WvString errstring
 

Detailed Description

A circular queue that can be accessed across fork().

Definition at line 14 of file wvmagiccircle.h.

Constructor & Destructor Documentation

◆ WvMagicCircle()

WvMagicCircle::WvMagicCircle ( size_t  size)

Creates a shared memory circular queue.

"size" is the number of elements to store

Definition at line 11 of file wvmagiccircle.cc.

References WvErrorBase::geterr(), and WvErrorBase::seterr().

Member Function Documentation

◆ isok()

virtual bool WvErrorBase::isok ( ) const
inlinevirtualinherited

By default, returns true if geterr() == 0.

Might be overridden so that isok() == false even though no error code has been specified.

Reimplemented in IWvStream, WvEncoderStream, WvReadLineStream, WvTCPConn, WvNullListener, WvFdStream, WvLog, WvStream, WvStreamClone, WvSSLStream, WvDBusServer, WvDSAKey, WvTimeStream, WvBufStream, WvListener, WvTimeoutStream, WvIStreamList, and _WvConStream.

Definition at line 39 of file wverror.h.

Referenced by WvListener::isok(), WvStream::isok(), and WvGlob::set().

◆ geterr()

virtual int WvErrorBase::geterr ( ) const
inlinevirtualinherited

If isok() is false, return the system error number corresponding to the error, -1 for a special error string (which you can obtain with errstr()) or 0 on end of file.

If isok() is true, returns an undefined number.

Reimplemented in WvStreamClone, and WvDBusServer.

Definition at line 48 of file wverror.h.

Referenced by UniIniGen::commit(), UniFileSystemGen::get(), WvDBusServer::geterr(), WvStreamClone::geterr(), WvEncoderStream::isok(), UniConfDaemon::listen(), WvStream::seterr(), and WvMagicCircle().

◆ seterr()

void WvErrorBase::seterr ( int  _errnum)
virtualinherited

Set the errnum variable – we have an error.

If called more than once, seterr() doesn't change the error code away from the previous one. That way, we remember the original cause of our problems.

Subclasses may want to override seterr(int) to shut themselves down (eg. WvStream::close()) when an error condition is set.

Note that seterr(WvString) will call seterr(-1).

Reimplemented in WvStream.

Definition at line 144 of file wverror.cc.

Referenced by WvUnixListener::accept(), WvTCPListener::accept(), WvDSAKey::getpem(), WvGlob::set(), WvStream::seterr(), WvMagicCircle(), WvPam::WvPam(), WvShmZone::WvShmZone(), and WvTCPListener::WvTCPListener().


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