Binary Semaphore #53

New Issue

muellerr · 2020-04-22T19:34:28+02:00

muellerr commented

2020-04-22 19:34:28 +02:00

I am trying to find a way to integrate binary semaphores as a signalling mechanism. The basic minimal interface is equivalent to the MUtexIF, but if we use the same interface, we would need to rename it to SemaphoreIF, and call the function lock() und unlock().

I am also not sure that putting both in the same interface is a good idea because they are used for different purposes (mutual exclusion <-> synchronization) and a class should only do one thing. Most APIs use give/take, release/obtain, notify/wait instead of lock/unlock anyway.

For our specific mission code, I still need the capability so give or take a semaphore with an external handle and I need to access the semaphore handle directly(which is private for the mutex for example). There are also other issues I will address in a separate issue.

For Linux, there seems to be an API for semaphores:
http://openbook.rheinwerk-verlag.de/linux_unix_programmierung/Kap10-006.htm#RxxKap10006040003201F0281B2

For RTEMS, there is a semaphore manager:
https://docs.rtems.org/branches/master/c-user/semaphore_manager.html

And with C++11 on linux, one can also build a binary semaphore
with language features apparentely:
https://stackoverflow.com/questions/4792449/c0x-has-no-semaphores-how-to-synchronize-threads

What do you think?

I am trying to find a way to integrate binary semaphores as a signalling mechanism. The basic minimal interface is equivalent to the MUtexIF, but if we use the same interface, we would need to rename it to SemaphoreIF, and call the function lock() und unlock(). I am also not sure that putting both in the same interface is a good idea because they are used for different purposes (mutual exclusion <-> synchronization) and a class should only do one thing. Most APIs use give/take, release/obtain, notify/wait instead of lock/unlock anyway. For our specific mission code, I still need the capability so give or take a semaphore with an external handle and I need to access the semaphore handle directly(which is private for the mutex for example). There are also other issues I will address in a separate issue. For Linux, there seems to be an API for semaphores: http://openbook.rheinwerk-verlag.de/linux_unix_programmierung/Kap10-006.htm#RxxKap10006040003201F0281B2 For RTEMS, there is a semaphore manager: https://docs.rtems.org/branches/master/c-user/semaphore_manager.html And with C++11 on linux, one can also build a binary semaphore with language features apparentely: https://stackoverflow.com/questions/4792449/c0x-has-no-semaphores-how-to-synchronize-threads What do you think?

muellerr added the

feature

label 2020-04-22 19:34:28 +02:00

muellerr referenced a pull request that will close this issue

2020-04-22 19:45:28 +02:00

binary semaphore init #54

muellerr added the

help wanted

label 2020-04-23 14:29:39 +02:00

muellerr referenced a pull request that will close this issue

2020-08-25 18:35:27 +02:00

Semaphore Initialization - Linux and FreeRTOS #89