Counting semaphore with maximum count constraint. More...
#include <semaphores.h>
Public Member Functions | |
| semaphore () | |
| Constructs a semaphore with maximum count. | |
| semaphore (u_integer init_count) | |
| Constructs a semaphore with specified initial count. | |
| void | acquire () |
| Acquires one resource (decrements count) | |
| bool | tryAcquire () |
| Attempts to acquire one resource without blocking. | |
| bool | acquireFor (time::duration timeout) |
| Attempts to acquire one resource with timeout. | |
| void | release (u_integer increase=1) |
| Releases resources (increments count) | |
| bool | tryRelease (u_integer increase=1) |
| Attempts to release resources without blocking. | |
| bool | releaseFor (u_integer increase, time::duration timeout) |
| Attempts to release resources with timeout. | |
| bool | releaseFor (const time::duration &timeout) |
| Attempts to release one resource with timeout. | |
Detailed Description
class original::semaphore< MAX_CNT >
Counting semaphore with maximum count constraint.
Specialization for unbounded semaphore (no maximum count)
- Template Parameters
-
MAX_CNT Maximum allowed semaphore count (default: 1, binary semaphore)
A counting semaphore that controls access to a shared resource pool. The semaphore count represents the number of available resources. acquire() waits for an available resource, while release() returns a resource to the pool.
For MAX_CNT = 1, behaves as a binary semaphore/mutex. For MAX_CNT > 1, implements a counting semaphore for resource pools. For MAX_CNT = 0, see specialization below for unbounded semaphore.
A semaphore with no upper limit on the count. release() operations never block, as there's no constraint on the maximum semaphore value.
Constructor & Destructor Documentation
◆ semaphore() [1/2]
| original::semaphore< MAX_CNT >::semaphore | ( | ) |
Constructs a semaphore with maximum count.
Initializes the semaphore with MAX_CNT available resources
◆ semaphore() [2/2]
|
explicit |
Constructs a semaphore with specified initial count.
- Parameters
-
init_count Initial semaphore count
- Exceptions
-
valueError if init_count exceeds MAX_CNT
Member Function Documentation
◆ acquire()
| void original::semaphore< MAX_CNT >::acquire | ( | ) |
Acquires one resource (decrements count)
Blocks the calling thread until a resource becomes available (count > 0). Decrements the semaphore count by 1 upon successful acquisition.
◆ acquireFor()
| bool original::semaphore< MAX_CNT >::acquireFor | ( | time::duration | timeout | ) |
Attempts to acquire one resource with timeout.
- Parameters
-
timeout Maximum duration to wait for resource availability
- Returns
- true if resource was acquired within timeout, false otherwise
◆ release()
| void original::semaphore< MAX_CNT >::release | ( | u_integer | increase = 1 | ) |
Releases resources (increments count)
- Parameters
-
increase Number of resources to release (default: 1)
- Exceptions
-
valueError if increase would exceed MAX_CNT
Blocks if releasing would exceed MAX_CNT, waiting until space becomes available. Notifies waiting threads after successful release.
◆ releaseFor() [1/2]
| bool original::semaphore< MAX_CNT >::releaseFor | ( | const time::duration & | timeout | ) |
Attempts to release one resource with timeout.
- Parameters
-
timeout Maximum duration to wait for release condition
- Returns
- true if resource was released within timeout, false otherwise
◆ releaseFor() [2/2]
| bool original::semaphore< MAX_CNT >::releaseFor | ( | u_integer | increase, |
| time::duration | timeout | ||
| ) |
Attempts to release resources with timeout.
- Parameters
-
increase Number of resources to release timeout Maximum duration to wait for release condition
- Returns
- true if resources were released within timeout, false otherwise
◆ tryAcquire()
| bool original::semaphore< MAX_CNT >::tryAcquire | ( | ) |
Attempts to acquire one resource without blocking.
- Returns
- true if resource was acquired, false if no resources available
◆ tryRelease()
| bool original::semaphore< MAX_CNT >::tryRelease | ( | u_integer | increase = 1 | ) |
Attempts to release resources without blocking.
- Parameters
-
increase Number of resources to release (default: 1)
- Returns
- true if resources were released, false if release would exceed MAX_CNT
The documentation for this class was generated from the following file:
- src/vibrant/semaphores.h
