Mutex

Mutual exclusion. More...

Collaboration diagram for Mutex:

Typedefs
typedef struct __tag_mutex	GF_Mutex
	abstracted mutex object

Functions
GF_Mutex *	gf_mx_new (const char *name)
	mutex constructor More...
void	gf_mx_del (GF_Mutex *mx)
	mutex denstructor More...
u32	gf_mx_p (GF_Mutex *mx)
	mutex locking More...
void	gf_mx_v (GF_Mutex *mx)
	mutex unlocking More...
Bool	gf_mx_try_lock (GF_Mutex *mx)
	mutex non-blocking lock More...
s32	gf_mx_get_num_locks (GF_Mutex *mx)
	get mutex number of locks More...

Detailed Description

The mutex object allows ensuring that portions of the code (typically access to variables) cannot be executed by two threads (or a thread and the main process) at the same time.

Function Documentation

gf_mx_new()

GF_Mutex* gf_mx_new

(

const char *

name

)

Contructs a new mutex object

Parameters

name	log name of the thread if any

Returns

new mutex

gf_mx_del()

void gf_mx_del

(

GF_Mutex *

mx

)

Destroys a mutex object. This will wait for the mutex to be released if needed.

Parameters

mx	the mutex object, may be NULL

gf_mx_p()

u32 gf_mx_p

(

GF_Mutex *

mx

)

Locks the mutex object, making sure that another thread locking this mutex cannot execute until the mutex is unlocked.

Parameters

mx	the mutex object, may be NULL

Returns

1 if success or mutex is NULL, 0 if error locking the mutex (which should never happen)

gf_mx_v()

void gf_mx_v

(

GF_Mutex *

mx

)

Unlocks the mutex object, allowing other threads waiting on this mutex to continue their execution

Parameters

mx	the mutex object, may be NULL

gf_mx_try_lock()

Bool gf_mx_try_lock

(

GF_Mutex *

mx

)

Attemps to lock the mutex object without blocking until the object is released.

Parameters

mx	the mutex object, may be NULL

Returns

GF_TRUE if the mutex has been successfully locked or if the mutex is NULL, in which case it shall then be unlocked, or GF_FALSE if the mutex is locked by another thread.

gf_mx_get_num_locks()

s32 gf_mx_get_num_locks

(

GF_Mutex *

mx

)

Returns the number of locks on the mutex if the caller thread is holding the mutex.

Parameters

mx	the mutex object, may be NULL

Returns

-1 if the mutex is not hold by the calling thread, or the number of locks (possibly 0) otherwise. Returns 0 if mutex is NULL