StaticRecMutex

Description Threads act almost like processes, but unlike processes all threads of one process share the same memory. This is good, as it provides easy communication between the involved threads via this shared memory, and it is bad, because strange things (so called "Heisenbugs") might happen if the program is not carefully designed. In particular, due to the concurrent nature of threads, no assumptions on the order of execution of code running in different threads can be made, unless order is explicitly forced by the programmer through synchronization primitives. The aim of the thread related functions in GLib is to provide a portable means for writing multi-threaded software. There are primitives for mutexes to protect the access to portions of memory (GMutex, GStaticMutex, G_LOCK_DEFINE, GStaticRecMutex and GStaticRWLock). There are primitives for condition variables to allow synchronization of threads (GCond). There are primitives for thread-private data - data that every thread has a private instance of (GPrivate, GStaticPrivate). Last but definitely not least there are primitives to portably create and manage threads (GThread). The threading system is initialized with g_thread_init(), which takes an optional custom thread implementation or NULL for the default implementation. If you want to call g_thread_init() with a non-NULL argument this must be done before executing any other GLib functions (except g_mem_set_vtable()). This is a requirement even if no threads are in fact ever created by the process. Calling g_thread_init() with a NULL argument is somewhat more relaxed. You may call any other glib functions in the main thread before g_thread_init() as long as g_thread_init() is not called from a glib callback, or with any locks held. However, many libraries above glib does not support late initialization of threads, so doing this should be avoided if possible. Please note that since version 2.24 the GObject initialization function g_type_init() initializes threads (with a NULL argument), so most applications, including those using Gtk+ will run with threads enabled. If you want a special thread implementation, make sure you call g_thread_init() before g_type_init() is called. After calling g_thread_init(), GLib is completely thread safe (all global data is automatically locked), but individual data structure instances are not automatically locked for performance reasons. So, for example you must coordinate accesses to the same GHashTable from multiple threads. The two notable exceptions from this rule are GMainLoop and GAsyncQueue, which are threadsafe and need no further application-level locking to be accessed from multiple threads. To help debugging problems in multithreaded applications, GLib supports error-checking mutexes that will give you helpful error messages on common problems. To use error-checking mutexes, define the symbol G_ERRORCHECK_MUTEXES when compiling the application.

Constructors

this
this(GStaticRecMutex* gStaticRecMutex)

Sets our main struct and passes it to the parent class

this
this()

Creates a new initialized StaticRecMutex.

Members

Functions

free
void free()

Releases all resources allocated to a GStaticRecMutex. You don't have to call this functions for a GStaticRecMutex with an unbounded lifetime, i.e. objects declared 'static', but if you have a GStaticRecMutex as a member of a structure and the structure is freed, you should also free the GStaticRecMutex.

getStaticRecMutexStruct
GStaticRecMutex* getStaticRecMutexStruct()
Undocumented in source. Be warned that the author may not have intended to support it.
getStruct
void* getStruct()

the main Gtk struct as a void*

init
void init()

A GStaticRecMutex must be initialized with this function before it can be used. Alternatively you can initialize it with G_STATIC_REC_MUTEX_INIT.

lock
void lock()

Locks mutex. If mutex is already locked by another thread, the current thread will block until mutex is unlocked by the other thread. If mutex is already locked by the calling thread, this functions increases the depth of mutex and returns immediately.

lockFull
void lockFull(uint depth)

Works like calling g_static_rec_mutex_lock() for mutex depth times.

trylock
int trylock()

Tries to lock mutex. If mutex is already locked by another thread, it immediately returns FALSE. Otherwise it locks mutex and returns TRUE. If mutex is already locked by the calling thread, this functions increases the depth of mutex and immediately returns TRUE.

unlock
void unlock()

Unlocks mutex. Another thread will be allowed to lock mutex only when it has been unlocked as many times as it had been locked before. If mutex is completely unlocked and another thread is blocked in a g_static_rec_mutex_lock() call for mutex, it will be woken and can lock mutex itself.

unlockFull
uint unlockFull()

Completely unlocks mutex. If another thread is blocked in a g_static_rec_mutex_lock() call for mutex, it will be woken and can lock mutex itself. This function returns the number of times that mutex has been locked by the current thread. To restore the state before the call to g_static_rec_mutex_unlock_full() you can call g_static_rec_mutex_lock_full() with the depth returned by this function.

Variables

gStaticRecMutex
GStaticRecMutex* gStaticRecMutex;

the main Gtk struct

Meta