Read/write locks

Read/write locks are a type of thread synchronization primitive meant to protect access to data that is mostly read, and rarely written. More...

Collaboration diagram for Read/write locks:

Macros
#define	VLC_STATIC_RWLOCK   PTHREAD_RWLOCK_INITIALIZER
	Static initializer for (static) read/write lock. More...

Typedefs
typedef pthread_rwlock_t	vlc_rwlock_t
	Read/write lock. More...

Functions
void	vlc_rwlock_init (vlc_rwlock_t *)
	Initializes a read/write lock. More...
void	vlc_rwlock_destroy (vlc_rwlock_t *)
	Destroys an initialized unused read/write lock. More...
void	vlc_rwlock_rdlock (vlc_rwlock_t *)
	Acquires a read/write lock for reading. More...
void	vlc_rwlock_wrlock (vlc_rwlock_t *)
	Acquires a read/write lock for writing. More...
void	vlc_rwlock_unlock (vlc_rwlock_t *)
	Releases a read/write lock. More...

Detailed Description

Read/write locks are a type of thread synchronization primitive meant to protect access to data that is mostly read, and rarely written.

As long as no threads tries to acquire the lock for "writing", any number of threads can acquire the lock for "reading".

See also POSIX pthread_rwlock_t .

Macro Definition Documentation

VLC_STATIC_RWLOCK

#define VLC_STATIC_RWLOCK   PTHREAD_RWLOCK_INITIALIZER

Static initializer for (static) read/write lock.

Typedef Documentation

vlc_rwlock_t

typedef pthread_rwlock_t vlc_rwlock_t

Read/write lock.

Storage space for a slim reader/writer lock.

Function Documentation

vlc_rwlock_destroy()

void vlc_rwlock_destroy

(

vlc_rwlock_t *

)

Destroys an initialized unused read/write lock.

References VLC_THREAD_ASSERT.

Referenced by _DLL_InitTerm(), DllMain(), vlc_cond_timedwait_daytime(), and vlc_LogSwitchClose().

vlc_rwlock_init()

void vlc_rwlock_init

(

vlc_rwlock_t *

)

Initializes a read/write lock.

After use, a read/write lock must be deinitialized with vlc_rwlock_destroy().

References unlikely.

Referenced by _DLL_InitTerm(), DllMain(), vlc_cond_timedwait_daytime(), and vlc_LogSwitchCreate().

vlc_rwlock_rdlock()

void vlc_rwlock_rdlock

(

vlc_rwlock_t *

)

Acquires a read/write lock for reading.

Note

Recursion is allowed.

This function may be a point of cancellation.

References VLC_THREAD_ASSERT.

Referenced by config_AutoSaveConfigFile(), config_GetFloat(), config_GetInt(), config_GetPsz(), config_SaveConfigFile(), vlc_cond_timedwait_daytime(), and vlc_vaLogSwitch().

vlc_rwlock_unlock()

void vlc_rwlock_unlock

(

vlc_rwlock_t *

)

Releases a read/write lock.

The calling thread must hold the lock. Otherwise behaviour is undefined.

Note

This function is not a cancellation point.

References VLC_THREAD_ASSERT.

Referenced by config_AutoSaveConfigFile(), config_GetFloat(), config_GetInt(), config_GetPsz(), config_LoadConfigFile(), config_PutFloat(), config_PutInt(), config_PutPsz(), config_ResetAll(), config_SaveConfigFile(), vlc_cond_timedwait_daytime(), vlc_LogSwitch(), and vlc_vaLogSwitch().

vlc_rwlock_wrlock()

void vlc_rwlock_wrlock

(

vlc_rwlock_t *

)

Acquires a read/write lock for writing.

Recursion is not allowed.

Note

This function may be a point of cancellation.

References VLC_THREAD_ASSERT.

Referenced by config_LoadConfigFile(), config_PutFloat(), config_PutInt(), config_PutPsz(), config_ResetAll(), vlc_cond_timedwait_daytime(), and vlc_LogSwitch().