Threading
Libobs provides a number of helper functions/types specifically for threading. The threading header will additionally provide access to pthread functions even on Windows.
#include <util/threading.h>
Threading Types
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type os_event_t
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type os_sem_t
General Thread Functions
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void os_set_thread_name(const char *name)
Sets the name of the current thread.
Event Functions
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int os_event_init(os_event_t **event, enum os_event_type type)
Creates an event object.
- Parameters:
event – Pointer that receives a pointer to a new event object
type –
Can be one of the following values:
OS_EVENT_TYPE_AUTO - Automatically resets when signaled
OS_EVENT_TYPE_MANUAL - Stays signaled until the
os_event_reset()function is called
- Returns:
0 if successful, negative otherwise
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void os_event_destroy(os_event_t *event)
Destroys an event.
- Parameters:
event – An event object
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int os_event_wait(os_event_t *event)
Waits for an event to signal.
- Parameters:
event – An event object
- Returns:
0 if successful, negative otherwise
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int os_event_timedwait(os_event_t *event, unsigned long milliseconds)
Waits a specific duration for an event to signal.
- Parameters:
event – An event object
milliseconds – Milliseconds to wait
- Returns:
Can be one of the following values:
0 - successful
ETIMEDOUT - Timed out
EINVAL - An unexpected error occurred
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int os_event_try(os_event_t *event)
Checks for a signaled state without waiting.
- Parameters:
event – An event object
- Returns:
Can be one of the following values:
0 - successful
EAGAIN - The event is not signaled
EINVAL - An unexpected error occurred
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int os_event_signal(os_event_t *event)
Signals the event.
- Parameters:
event – An event object
- Returns:
0 if successful, negative otherwise
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void os_event_reset(os_event_t *event)
Resets the signaled state of the event.
- Parameters:
event – An event object
Semaphore Functions
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int os_sem_init(os_sem_t **sem, int value)
Creates a semaphore object.
- Parameters:
sem – Pointer that receives a pointer to the semaphore object
value – Initial value of the semaphore
- Returns:
0 if successful, negative otherwise
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int os_sem_post(os_sem_t *sem)
Increments the semaphore.
- Parameters:
sem – Semaphore object
- Returns:
0 if successful, negative otherwise
Atomic Inline Functions
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long os_atomic_inc_long(volatile long *val)
Increments a long variable atomically.
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long os_atomic_dec_long(volatile long *val)
Decrements a long variable atomically.
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void os_atomic_store_long(volatile long *ptr, long val)
Stores the value of a long variable atomically.
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long os_atomic_set_long(volatile long *ptr, long val)
Exchanges the value of a long variable atomically. Badly named.
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long os_atomic_exchange_long(volatile long *ptr, long val)
Exchanges the value of a long variable atomically. Properly named.
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long os_atomic_load_long(volatile const long *ptr)
Gets the value of a long variable atomically.
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bool os_atomic_compare_swap_long(volatile long *val, long old_val, long new_val)
Swaps the value of a long variable atomically if its value matches.
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void os_atomic_store_bool(volatile bool *ptr, bool val)
Stores the value of a boolean variable atomically.
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bool os_atomic_set_bool(volatile bool *ptr, bool val)
Exchanges the value of a boolean variable atomically. Badly named.
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bool os_atomic_exchange_bool(volatile bool *ptr, bool val)
Exchanges the value of a boolean variable atomically. Properly named.
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bool os_atomic_load_bool(volatile const bool *ptr)
Gets the value of a boolean variable atomically.