cmlabs::utils::Semaphore Class Reference

Counting semaphore, optionally named for cross-process use. More...

#include <Utils.h>

Public Member Functions
	Semaphore (uint32 maxCount=100)
	Create an anonymous semaphore.
	Semaphore (const char *name, uint32 maxCount=100)
	Create or open a named, cross-process semaphore.
	~Semaphore ()
bool	wait ()
	Block until the semaphore can be decremented.
bool	wait (uint32 timeout)
	Wait with a timeout.
bool	signal ()
	Increment (release) the semaphore, waking one waiter.

Public Attributes
char *	name

Protected Attributes
sem_t *	semaphore

Detailed Description

Counting semaphore, optionally named for cross-process use.

On macOS an unnamed semaphore uses libdispatch (dispatch_semaphore_t) while named ones are emulated in shared memory, because POSIX unnamed semaphores are unsupported there — hence the void* semaphore_impl member.

Definition at line 502 of file Utils.h.

Constructor & Destructor Documentation

Semaphore() [1/2]

cmlabs::utils::Semaphore::Semaphore

(

uint32

maxCount = 100

)

Create an anonymous semaphore.

Parameters

maxCount

Maximum count (Windows honours it strictly).

Definition at line 1270 of file Utils.cpp.

References name, and semaphore.

Semaphore() [2/2]

cmlabs::utils::Semaphore::Semaphore	(	const char *	name,
		uint32	maxCount = 100 )

Create or open a named, cross-process semaphore.

Parameters

name	Global name.
maxCount	Maximum count.

Definition at line 1291 of file Utils.cpp.

References cmlabs::utils::CreateSharedMemorySegment(), MAXKEYNAMELEN, MAXSHMEMNAMELEN, name, cmlabs::utils::OpenSharedMemorySegment(), semaphore, SEMAPHOREMEMSIZE, cmlabs::utils::strcpyavail(), and WINSHMEMSPACE.

~Semaphore()

cmlabs::utils::Semaphore::~Semaphore

(

)

Definition at line 1340 of file Utils.cpp.

References cmlabs::utils::CloseSharedMemorySegment(), name, semaphore, and SEMAPHOREMEMSIZE.

Member Function Documentation

signal()

bool cmlabs::utils::Semaphore::signal

(

)

Increment (release) the semaphore, waking one waiter.

Returns

true on success.

Definition at line 1444 of file Utils.cpp.

References name, and semaphore.

Referenced by cmlabs::utils::SignalSemaphore().

wait() [1/2]

bool cmlabs::utils::Semaphore::wait

(

)

Block until the semaphore can be decremented.

Returns

true on success.

Definition at line 1375 of file Utils.cpp.

References name, and semaphore.

Referenced by cmlabs::utils::WaitForSemaphore().

wait() [2/2]

bool cmlabs::utils::Semaphore::wait

(

uint32

timeout

)

Wait with a timeout.

Parameters

timeout

Max wait in milliseconds.

Returns

true when acquired, false on timeout.

Definition at line 1402 of file Utils.cpp.

References cmlabs::utils::CalcTimeout(), name, and semaphore.

Member Data Documentation

name

char* cmlabs::utils::Semaphore::name

Definition at line 516 of file Utils.h.

Referenced by Semaphore(), Semaphore(), signal(), wait(), wait(), and ~Semaphore().

semaphore

sem_t* cmlabs::utils::Semaphore::semaphore

protected

Definition at line 524 of file Utils.h.

Referenced by Semaphore(), Semaphore(), signal(), wait(), wait(), and ~Semaphore().

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

• /home/ubuntu/c/partner/psyclone2/CMSDK/include/Utils.h
• /home/ubuntu/c/partner/psyclone2/CMSDK/src/Utils.cpp