#include "gthread.h"
#include "gthreadprivate.h"
-#include "deprecated/gthread.h"
#include <string.h>
#include <windows.h>
#endif /* G_OS_WIN32 */
-#include "garray.h"
#include "gslice.h"
-#include "gslist.h"
#include "gtestutils.h"
/**
* individual bits for locks (g_bit_lock()). 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). There are
+ * has a private instance of (#GPrivate). There are
* facilities for one-time initialization (#GOnce, g_once_init_enter()).
* Finally there are primitives to create and manage threads (#GThread).
*
- * The threading system is initialized with g_thread_init().
- * 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. Since 2.32, creating
- * a mainloop will do so too. As a consequence, most applications,
- * including those using GTK+ will run with threads enabled.
- *
- * 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 <emphasis>are</emphasis>
- * threadsafe and need no further application-level locking to be
- * accessed from multiple threads.
- */
-
-/**
- * G_THREADS_IMPL_POSIX:
- *
- * This macro is defined if POSIX style threads are used.
- */
-
-/**
- * G_THREADS_IMPL_WIN32:
- *
- * This macro is defined if Windows style threads are used.
+ * The GLib threading system used to be initialized with g_thread_init().
+ * This is no longer necessary. Since version 2.32, the GLib threading
+ * system is automatically initialized at the start of your program,
+ * and all thread-creation functions and synchronization primitives
+ * are available right away. It is still possible to do thread-unsafe
+ * initialization and setup at the beginning of your program, before
+ * creating the first threads.
+ *
+ * GLib is internally completely thread-safe (all global data is
+ * automatically locked), but individual data structure instances are
+ * not automatically locked for performance reasons. 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 <emphasis>are</emphasis> thread-safe and
+ * need no further application-level locking to be accessed from
+ * multiple threads. Most refcounting functions such as g_object_ref()
+ * are also thread-safe.
*/
/* G_LOCK Documentation {{{1 ---------------------------------------------- */
/**
* G_LOCK_DEFINE:
- * @name: the name of the lock.
+ * @name: the name of the lock
*
- * The %G_LOCK_* macros provide a convenient interface to #GMutex
- * with the advantage that they will expand to nothing in programs
- * compiled against a thread-disabled GLib, saving code and memory
- * there. #G_LOCK_DEFINE defines a lock. It can appear anywhere
+ * The %G_LOCK_* macros provide a convenient interface to #GMutex.
+ * #G_LOCK_DEFINE defines a lock. It can appear in any place where
* variable definitions may appear in programs, i.e. in the first block
* of a function or outside of functions. The @name parameter will be
* mangled to get the name of the #GMutex. This means that you
* can use names of existing variables as the parameter - e.g. the name
- * of the variable you intent to protect with the lock. Look at our
+ * of the variable you intend to protect with the lock. Look at our
* <function>give_me_next_number()</function> example using the
* %G_LOCK_* macros:
*
/**
* G_LOCK_DEFINE_STATIC:
- * @name: the name of the lock.
+ * @name: the name of the lock
*
* This works like #G_LOCK_DEFINE, but it creates a static object.
*/
/**
* G_LOCK_EXTERN:
- * @name: the name of the lock.
+ * @name: the name of the lock
*
* This declares a lock, that is defined with #G_LOCK_DEFINE in another
* module.
/**
* G_LOCK:
- * @name: the name of the lock.
+ * @name: the name of the lock
*
* Works like g_mutex_lock(), but for a lock defined with
* #G_LOCK_DEFINE.
/**
* G_TRYLOCK:
- * @name: the name of the lock.
+ * @name: the name of the lock
* @Returns: %TRUE, if the lock could be locked.
*
* Works like g_mutex_trylock(), but for a lock defined with
/**
* G_UNLOCK:
- * @name: the name of the lock.
+ * @name: the name of the lock
*
* Works like g_mutex_unlock(), but for a lock defined with
* #G_LOCK_DEFINE.
*
* It is easy to see that this won't work in a multi-threaded
* application. There current_number must be protected against shared
- * access. A first naive implementation would be:
- *
- * <example>
- * <title>The wrong way to write a thread-safe function</title>
- * <programlisting>
- * int
- * give_me_next_number (void)
- * {
- * static int current_number = 0;
- * int ret_val;
- * static GMutex * mutex = NULL;
- *
- * if (!mutex) mutex = g_mutex_new (<!-- -->);
- *
- * g_mutex_lock (mutex);
- * ret_val = current_number = calc_next_number (current_number);
- * g_mutex_unlock (mutex);
- *
- * return ret_val;
- * }
- * </programlisting>
- * </example>
- *
- * This looks like it would work, but there is a race condition while
- * constructing the mutex and this code cannot work reliable. Please do
- * not use such constructs in your own programs! One working solution
- * is:
- *
- * <example>
- * <title>A correct thread-safe function</title>
- * <programlisting>
- * static GMutex *give_me_next_number_mutex = NULL;
- *
- * /<!-- -->* this function must be called before any call to
- * * give_me_next_number(<!-- -->)
- * *
- * * it must be called exactly once.
- * *<!-- -->/
- * void
- * init_give_me_next_number (void)
- * {
- * g_assert (give_me_next_number_mutex == NULL);
- * give_me_next_number_mutex = g_mutex_new (<!-- -->);
- * }
- *
- * int
- * give_me_next_number (void)
- * {
- * static int current_number = 0;
- * int ret_val;
- *
- * g_mutex_lock (give_me_next_number_mutex);
- * ret_val = current_number = calc_next_number (current_number);
- * g_mutex_unlock (give_me_next_number_mutex);
- *
- * return ret_val;
- * }
- * </programlisting>
- * </example>
- *
- * A statically initialized #GMutex provides an even simpler and safer
- * way of doing this:
+ * access. A #GMutex can be used as a solution to this problem:
*
* <example>
- * <title>Using a statically allocated mutex</title>
+ * <title>Using GMutex to protected a shared variable</title>
* <programlisting>
* int
* give_me_next_number (void)
* {
- * static GMutex mutex = G_MUTEX_INIT;
+ * static GMutex mutex;
* static int current_number = 0;
* int ret_val;
*
* </programlisting>
* </example>
*
- * A #GMutex should only be accessed via <function>g_mutex_</function>
- * functions.
- */
-
-/**
- * G_MUTEX_INIT:
+ * Notice that the #GMutex is not initialised to any particular value.
+ * Its placement in static storage ensures that it will be initialised
+ * to all-zeros, which is appropriate.
*
- * Initializer for statically allocated #GMutexes.
- * Alternatively, g_mutex_init() can be used.
+ * If a #GMutex is placed in other contexts (eg: embedded in a struct)
+ * then it must be explicitly initialised using g_mutex_init().
*
- * |[
- * GMutex mutex = G_MUTEX_INIT;
- * ]|
- *
- * Since: 2.32
+ * A #GMutex should only be accessed via <function>g_mutex_</function>
+ * functions.
*/
/* GRecMutex Documentation {{{1 -------------------------------------- */
* thread without deadlock. When doing so, care has to be taken to
* unlock the recursive mutex as often as it has been locked.
*
- * A GRecMutex should only be accessed with the
- * <function>g_rec_mutex_</function> functions. Before a GRecMutex
- * can be used, it has to be initialized with #G_REC_MUTEX_INIT or
- * g_rec_mutex_init().
+ * If a #GRecMutex is allocated in static storage then it can be used
+ * without initialisation. Otherwise, you should call
+ * g_rec_mutex_init() on it and g_rec_mutex_clear() when done.
*
- * Since: 2.32
- */
-
-/**
- * G_REC_MUTEX_INIT:
- *
- * Initializer for statically allocated #GRecMutexes.
- * Alternatively, g_rec_mutex_init() can be used.
- *
- * |[
- * GRecMutex mutex = G_REC_MUTEX_INIT;
- * ]|
+ * A GRecMutex should only be accessed with the
+ * <function>g_rec_mutex_</function> functions.
*
* Since: 2.32
*/
* <example>
* <title>An array with access functions</title>
* <programlisting>
- * GRWLock lock = G_RW_LOCK_INIT;
+ * GRWLock lock;
* GPtrArray *array;
*
* gpointer
* </para>
* </example>
*
- * A GRWLock should only be accessed with the
- * <function>g_rw_lock_</function> functions. Before it can be used,
- * it has to be initialized with #G_RW_LOCK_INIT or g_rw_lock_init().
- *
- * Since: 2.32
- */
-
-/**
- * G_RW_LOCK_INIT:
- *
- * Initializer for statically allocated #GRWLocks.
- * Alternatively, g_rw_lock_init_init() can be used.
+ * If a #GRWLock is allocated in static storage then it can be used
+ * without initialisation. Otherwise, you should call
+ * g_rw_lock_init() on it and g_rw_lock_clear() when done.
*
- * |[
- * GRWLock lock = G_RW_LOCK_INIT;
- * ]|
+ * A GRWLock should only be accessed with the
+ * <function>g_rw_lock_</function> functions.
*
* Since: 2.32
*/
* condition they signal the #GCond, and that causes the waiting
* threads to be woken up.
*
+ * Consider the following example of a shared variable. One or more
+ * threads can wait for data to be published to the variable and when
+ * another thread publishes the data, it can signal one of the waiting
+ * threads to wake up to collect the data.
+ *
* <example>
* <title>
* Using GCond to block a thread until a condition is satisfied
* </title>
* <programlisting>
- * GCond* data_cond = NULL; /<!-- -->* Must be initialized somewhere *<!-- -->/
- * GMutex* data_mutex = NULL; /<!-- -->* Must be initialized somewhere *<!-- -->/
* gpointer current_data = NULL;
+ * GMutex data_mutex;
+ * GCond data_cond;
*
* void
* push_data (gpointer data)
* {
- * g_mutex_lock (data_mutex);
+ * g_mutex_lock (&data_mutex);
* current_data = data;
- * g_cond_signal (data_cond);
- * g_mutex_unlock (data_mutex);
+ * g_cond_signal (&data_cond);
+ * g_mutex_unlock (&data_mutex);
* }
*
* gpointer
* {
* gpointer data;
*
- * g_mutex_lock (data_mutex);
+ * g_mutex_lock (&data_mutex);
* while (!current_data)
- * g_cond_wait (data_cond, data_mutex);
+ * g_cond_wait (&data_cond, &data_mutex);
* data = current_data;
* current_data = NULL;
- * g_mutex_unlock (data_mutex);
+ * g_mutex_unlock (&data_mutex);
*
* return data;
* }
* current_data is non-%NULL, i.e. until some other thread
* has called push_data().
*
- * <note><para>It is important to use the g_cond_wait() and
- * g_cond_timed_wait() functions only inside a loop which checks for the
- * condition to be true. It is not guaranteed that the waiting thread
- * will find the condition fulfilled after it wakes up, even if the
- * signaling thread left the condition in that state: another thread may
- * have altered the condition before the waiting thread got the chance
- * to be woken up, even if the condition itself is protected by a
- * #GMutex, like above.</para></note>
+ * The example shows that use of a condition variable must always be
+ * paired with a mutex. Without the use of a mutex, there would be a
+ * race between the check of <varname>current_data</varname> by the
+ * while loop in <function>pop_data</function> and waiting.
+ * Specifically, another thread could set <varname>pop_data</varname>
+ * after the check, and signal the cond (with nobody waiting on it)
+ * before the first thread goes to sleep. #GCond is specifically useful
+ * for its ability to release the mutex and go to sleep atomically.
*
- * A #GCond should only be accessed via the <function>g_cond_</function>
- * functions.
- */
-
-/**
- * G_COND_INIT:
+ * It is also important to use the g_cond_wait() and g_cond_wait_until()
+ * functions only inside a loop which checks for the condition to be
+ * true. See g_cond_wait() for an explanation of why the condition may
+ * not be true even after it returns.
*
- * Initializer for statically allocated #GConds.
- * Alternatively, g_cond_init() can be used.
+ * If a #GCond is allocated in static storage then it can be used
+ * without initialisation. Otherwise, you should call g_cond_init() on
+ * it and g_cond_clear() when done.
*
- * |[
- * GCond cond = G_COND_INIT;
- * ]|
- *
- * Since: 2.32
+ * A #GCond should only be accessed via the <function>g_cond_</function>
+ * functions.
*/
/* GThread Documentation {{{1 ---------------------------------------- */
/**
* GThread:
*
- * The #GThread struct represents a running thread.
+ * The #GThread struct represents a running thread. This struct
+ * is returned by g_thread_new() or g_thread_try_new(). You can obtain
+ * the #GThread struct representing the current thead by calling
+ * g_thread_self().
*
- * Resources for a joinable thread are not fully released
- * until g_thread_join() is called for that thread.
+ * The structure is opaque -- none of its fields may be directly
+ * accessed.
*/
/**
* GThreadFunc:
* @data: data passed to the thread
- * @Returns: the return value of the thread, which will be returned by
- * g_thread_join()
*
- * Specifies the type of the @func functions passed to
- * g_thread_create() or g_thread_create_full().
+ * Specifies the type of the @func functions passed to g_thread_new() or
+ * g_thread_try_new().
+ *
+ * Returns: the return value of the thread
*/
/**
return g_quark_from_static_string ("g_thread_error");
}
-/* Miscellaneous Structures {{{1 ------------------------------------------ */
-
-typedef struct _GRealThread GRealThread;
-struct _GRealThread
-{
- GThread thread;
- GArray *private_data;
- GRealThread *next;
- gpointer retval;
- GSystemThread system_thread;
-};
-
/* Local Data {{{1 -------------------------------------------------------- */
-gboolean g_threads_got_initialized = FALSE;
-GSystemThread zero_thread; /* This is initialized to all zero */
-
-GMutex g_once_mutex = G_MUTEX_INIT;
-static GCond g_once_cond = G_COND_INIT;
+static GMutex g_once_mutex;
+static GCond g_once_cond;
static GSList *g_once_init_list = NULL;
static void g_thread_cleanup (gpointer data);
static GPrivate g_thread_specific_private = G_PRIVATE_INIT (g_thread_cleanup);
-static GRealThread *g_thread_all_threads = NULL;
-static GSList *g_thread_free_indices = NULL;
-
-/* Protects g_thread_all_threads and g_thread_free_indices */
-G_LOCK_DEFINE_STATIC (g_thread);
-
-/* Initialisation {{{1 ---------------------------------------------------- */
-
-/**
- * g_thread_init:
- * @vtable: a function table of type #GThreadFunctions, that provides
- * the entry points to the thread system to be used. Since 2.32,
- * this parameter is ignored and should always be %NULL
- *
- * If you use GLib from more than one thread, you must initialize the
- * thread system by calling g_thread_init().
- *
- * Since version 2.24, calling g_thread_init() multiple times is allowed,
- * but nothing happens except for the first call.
- *
- * Since version 2.32, GLib does not support custom thread implementations
- * anymore and the @vtable parameter is ignored and you should pass %NULL.
- *
- * <note><para>g_thread_init() must not be called directly or indirectly
- * in a callback from GLib. Also no mutexes may be currently locked while
- * calling g_thread_init().</para></note>
- *
- * <note><para>To use g_thread_init() in your program, you have to link
- * with the libraries that the command <command>pkg-config --libs
- * gthread-2.0</command> outputs. This is not the case for all the
- * other thread-related functions of GLib. Those can be used without
- * having to link with the thread libraries.</para></note>
- */
-
-void
-g_thread_init_glib (void)
-{
- static gboolean already_done;
- GRealThread* main_thread;
-
- if (already_done)
- return;
-
- already_done = TRUE;
- /* We let the main thread (the one that calls g_thread_init) inherit
- * the static_private data set before calling g_thread_init
- */
- main_thread = (GRealThread*) g_thread_self ();
-
- /* setup the basic threading system */
- g_threads_got_initialized = TRUE;
- g_private_set (&g_thread_specific_private, main_thread);
- g_system_thread_self (&main_thread->system_thread);
-
- /* accomplish log system initialization to enable messaging */
- _g_messages_thread_init_nomessage ();
-}
-
-/**
- * g_thread_get_initialized:
- *
- * Indicates if g_thread_init() has been called.
- *
- * Returns: %TRUE if threads have been initialized.
- *
- * Since: 2.20
- */
-gboolean
-g_thread_get_initialized (void)
-{
- return g_thread_supported ();
-}
+G_LOCK_DEFINE_STATIC (g_thread_new);
/* GOnce {{{1 ------------------------------------------------------------- */
* Since: 2.14
*/
gboolean
-g_once_init_enter_impl (volatile gsize *value_location)
+(g_once_init_enter) (volatile void *pointer)
{
+ volatile gsize *value_location = pointer;
gboolean need_init = FALSE;
g_mutex_lock (&g_once_mutex);
if (g_atomic_pointer_get (value_location) == NULL)
* g_once_init_leave:
* @value_location: location of a static initializable variable
* containing 0
- * @initialization_value: new non-0 value for *@value_location
+ * @result: new non-0 value for *@value_location
*
* Counterpart to g_once_init_enter(). Expects a location of a static
* 0-initialized initialization variable, and an initialization value
* Since: 2.14
*/
void
-g_once_init_leave (volatile gsize *value_location,
- gsize initialization_value)
+(g_once_init_leave) (volatile void *pointer,
+ gsize result)
{
+ volatile gsize *value_location = pointer;
+
g_return_if_fail (g_atomic_pointer_get (value_location) == NULL);
- g_return_if_fail (initialization_value != 0);
+ g_return_if_fail (result != 0);
g_return_if_fail (g_once_init_list != NULL);
- g_atomic_pointer_set (value_location, initialization_value);
+ g_atomic_pointer_set (value_location, result);
g_mutex_lock (&g_once_mutex);
g_once_init_list = g_slist_remove (g_once_init_list, (void*) value_location);
g_cond_broadcast (&g_once_cond);
g_mutex_unlock (&g_once_mutex);
}
-/* GStaticPrivate {{{1 ---------------------------------------------------- */
-
-typedef struct _GStaticPrivateNode GStaticPrivateNode;
-struct _GStaticPrivateNode
-{
- gpointer data;
- GDestroyNotify destroy;
- GStaticPrivate *owner;
-};
-
-/**
- * GStaticPrivate:
- *
- * A #GStaticPrivate works almost like a #GPrivate, but it has one
- * significant advantage. It doesn't need to be created at run-time
- * like a #GPrivate, but can be defined at compile-time. This is
- * similar to the difference between #GMutex and #GStaticMutex. Now
- * look at our <function>give_me_next_number()</function> example with
- * #GStaticPrivate:
- *
- * <example>
- * <title>Using GStaticPrivate for per-thread data</title>
- * <programlisting>
- * int
- * give_me_next_number (<!-- -->)
- * {
- * static GStaticPrivate current_number_key = G_STATIC_PRIVATE_INIT;
- * int *current_number = g_static_private_get (&current_number_key);
- *
- * if (!current_number)
- * {
- * current_number = g_new (int,1);
- * *current_number = 0;
- * g_static_private_set (&current_number_key, current_number, g_free);
- * }
- *
- * *current_number = calc_next_number (*current_number);
- *
- * return *current_number;
- * }
- * </programlisting>
- * </example>
- */
-
-/**
- * G_STATIC_PRIVATE_INIT:
- *
- * Every #GStaticPrivate must be initialized with this macro, before it
- * can be used.
- *
- * |[
- * GStaticPrivate my_private = G_STATIC_PRIVATE_INIT;
- * ]|
- */
-
-/**
- * g_static_private_init:
- * @private_key: a #GStaticPrivate to be initialized
- *
- * Initializes @private_key. Alternatively you can initialize it with
- * #G_STATIC_PRIVATE_INIT.
- */
-void
-g_static_private_init (GStaticPrivate *private_key)
-{
- private_key->index = 0;
-}
+/* GThread {{{1 -------------------------------------------------------- */
-/**
- * g_static_private_get:
- * @private_key: a #GStaticPrivate
- *
- * Works like g_private_get() only for a #GStaticPrivate.
- *
- * This function works even if g_thread_init() has not yet been called.
- *
- * Returns: the corresponding pointer
- */
-gpointer
-g_static_private_get (GStaticPrivate *private_key)
+GThread *
+g_thread_ref (GThread *thread)
{
- GRealThread *self = (GRealThread*) g_thread_self ();
- GArray *array;
- gpointer ret = NULL;
-
- array = self->private_data;
-
- if (array && private_key->index != 0 && private_key->index <= array->len)
- {
- GStaticPrivateNode *node;
+ GRealThread *real = (GRealThread *) thread;
- node = &g_array_index (array, GStaticPrivateNode, private_key->index - 1);
+ g_atomic_int_inc (&real->ref_count);
- /* Deal with the possibility that the GStaticPrivate which used
- * to have this index got freed and the index got allocated to
- * a new one. In this case, the data in the node is stale, so
- * free it and return NULL.
- */
- if (G_UNLIKELY (node->owner != private_key))
- {
- if (node->destroy)
- node->destroy (node->data);
- node->destroy = NULL;
- node->data = NULL;
- node->owner = NULL;
- }
-
- ret = node->data;
- }
-
- return ret;
+ return thread;
}
-/**
- * g_static_private_set:
- * @private_key: a #GStaticPrivate
- * @data: the new pointer
- * @notify: a function to be called with the pointer whenever the
- * current thread ends or sets this pointer again
- *
- * Sets the pointer keyed to @private_key for the current thread and
- * the function @notify to be called with that pointer (%NULL or
- * non-%NULL), whenever the pointer is set again or whenever the
- * current thread ends.
- *
- * This function works even if g_thread_init() has not yet been called.
- * If g_thread_init() is called later, the @data keyed to @private_key
- * will be inherited only by the main thread, i.e. the one that called
- * g_thread_init().
- *
- * <note><para>@notify is used quite differently from @destructor in
- * g_private_new().</para></note>
- */
void
-g_static_private_set (GStaticPrivate *private_key,
- gpointer data,
- GDestroyNotify notify)
+g_thread_unref (GThread *thread)
{
- GRealThread *self = (GRealThread*) g_thread_self ();
- GArray *array;
- static guint next_index = 0;
- GStaticPrivateNode *node;
-
- if (!private_key->index)
- {
- G_LOCK (g_thread);
+ GRealThread *real = (GRealThread *) thread;
- if (!private_key->index)
- {
- if (g_thread_free_indices)
- {
- private_key->index = GPOINTER_TO_UINT (g_thread_free_indices->data);
- g_thread_free_indices = g_slist_delete_link (g_thread_free_indices,
- g_thread_free_indices);
- }
- else
- private_key->index = ++next_index;
- }
-
- G_UNLOCK (g_thread);
- }
-
- array = self->private_data;
- if (!array)
+ if (g_atomic_int_dec_and_test (&real->ref_count))
{
- array = g_array_new (FALSE, TRUE, sizeof (GStaticPrivateNode));
- self->private_data = array;
+ if (real->ours)
+ g_system_thread_free (real);
+ else
+ g_slice_free (GRealThread, real);
}
-
- if (private_key->index > array->len)
- g_array_set_size (array, private_key->index);
-
- node = &g_array_index (array, GStaticPrivateNode, private_key->index - 1);
-
- if (node->destroy)
- node->destroy (node->data);
-
- node->data = data;
- node->destroy = notify;
- node->owner = private_key;
}
-/**
- * g_static_private_free:
- * @private_key: a #GStaticPrivate to be freed
- *
- * Releases all resources allocated to @private_key.
- *
- * You don't have to call this functions for a #GStaticPrivate with an
- * unbounded lifetime, i.e. objects declared 'static', but if you have
- * a #GStaticPrivate as a member of a structure and the structure is
- * freed, you should also free the #GStaticPrivate.
- */
-void
-g_static_private_free (GStaticPrivate *private_key)
-{
- guint idx = private_key->index;
-
- if (!idx)
- return;
-
- private_key->index = 0;
-
- /* Freeing the per-thread data is deferred to either the
- * thread end or the next g_static_private_get() call for
- * the same index.
- */
- G_LOCK (g_thread);
- g_thread_free_indices = g_slist_prepend (g_thread_free_indices,
- GUINT_TO_POINTER (idx));
- G_UNLOCK (g_thread);
-}
-
-/* GThread {{{1 -------------------------------------------------------- */
-
static void
g_thread_cleanup (gpointer data)
{
- if (data)
- {
- GRealThread* thread = data;
- GArray *array;
-
- array = thread->private_data;
- thread->private_data = NULL;
-
- if (array)
- {
- guint i;
-
- for (i = 0; i < array->len; i++ )
- {
- GStaticPrivateNode *node = &g_array_index (array, GStaticPrivateNode, i);
- if (node->destroy)
- node->destroy (node->data);
- }
- g_array_free (array, TRUE);
- }
-
- /* We only free the thread structure if it isn't joinable.
- * If it is, the structure is freed in g_thread_join()
- */
- if (!thread->thread.joinable)
- {
- GRealThread *t, *p;
-
- G_LOCK (g_thread);
- for (t = g_thread_all_threads, p = NULL; t; p = t, t = t->next)
- {
- if (t == thread)
- {
- if (p)
- p->next = t->next;
- else
- g_thread_all_threads = t->next;
- break;
- }
- }
- G_UNLOCK (g_thread);
-
- /* Just to make sure, this isn't used any more */
- g_system_thread_assign (thread->system_thread, zero_thread);
- g_free (thread);
- }
- }
+ g_thread_unref (data);
}
-static gpointer
-g_thread_create_proxy (gpointer data)
+gpointer
+g_thread_proxy (gpointer data)
{
GRealThread* thread = data;
g_assert (data);
+ if (thread->name)
+ g_system_thread_set_name (thread->name);
+
/* This has to happen before G_LOCK, as that might call g_thread_self */
g_private_set (&g_thread_specific_private, data);
- /* The lock makes sure that thread->system_thread is written,
- * before thread->thread.func is called. See g_thread_create().
+ /* The lock makes sure that g_thread_new_internal() has a chance to
+ * setup 'func' and 'data' before we make the call.
*/
- G_LOCK (g_thread);
- G_UNLOCK (g_thread);
+ G_LOCK (g_thread_new);
+ G_UNLOCK (g_thread_new);
thread->retval = thread->thread.func (thread->thread.data);
}
/**
- * g_thread_create:
+ * g_thread_new:
+ * @name: a name for the new thread
* @func: a function to execute in the new thread
* @data: an argument to supply to the new thread
- * @joinable: should this thread be joinable?
- * @error: return location for error, or %NULL
+ * @error: return location for error
*
- * This function creates a new thread.
+ * This function creates a new thread. The new thread starts by invoking
+ * @func with the argument data. The thread will run until @func returns
+ * or until g_thread_exit() is called from the new thread.
*
- * If @joinable is %TRUE, you can wait for this threads termination
- * calling g_thread_join(). Otherwise the thread will just disappear
- * when it terminates.
+ * The @name can be useful for discriminating threads in
+ * a debugger. Some systems restrict the length of @name to
+ * 16 bytes.
*
- * The new thread executes the function @func with the argument @data.
- * If the thread was created successfully, it is returned.
+ * If the thread can not be created the program aborts. See
+ * g_thread_try_new() if you want to attempt to deal with failures.
*
- * @error can be %NULL to ignore errors, or non-%NULL to report errors.
- * The error is set, if and only if the function returns %NULL.
+ * Returns: the new #GThread
*
- * Returns: the new #GThread on success
+ * Since: 2.32
*/
GThread *
-g_thread_create (GThreadFunc func,
- gpointer data,
- gboolean joinable,
- GError **error)
+g_thread_new (const gchar *name,
+ GThreadFunc func,
+ gpointer data)
{
- return g_thread_create_with_stack_size (func, data, joinable, 0, error);
+ GError *error = NULL;
+ GThread *thread;
+
+ thread = g_thread_new_internal (name, g_thread_proxy, func, data, 0, &error);
+
+ if G_UNLIKELY (thread == NULL)
+ g_error ("creating thread '%s': %s", name ? name : "", error->message);
+
+ return thread;
}
/**
- * g_thread_create_with_stack_size:
+ * g_thread_try_new:
+ * @name: a name for the new thread
* @func: a function to execute in the new thread
* @data: an argument to supply to the new thread
- * @joinable: should this thread be joinable?
- * @stack_size: a stack size for the new thread
- * @error: return location for error
- *
- * This function creates a new thread. If the underlying thread
- * implementation supports it, the thread gets a stack size of
- * @stack_size or the default value for the current platform, if
- * @stack_size is 0.
- *
- * If @joinable is %TRUE, you can wait for this threads termination
- * calling g_thread_join(). Otherwise the thread will just disappear
- * when it terminates.
- *
- * The new thread executes the function @func with the argument @data.
- * If the thread was created successfully, it is returned.
+ * @error: return location for error, or %NULL
*
- * @error can be %NULL to ignore errors, or non-%NULL to report errors.
- * The error is set, if and only if the function returns %NULL.
+ * This function is the same as g_thread_new() except that
+ * it allows for the possibility of failure.
*
- * <note><para>Only use g_thread_create_with_stack_size() if you
- * really can't use g_thread_create() instead. g_thread_create()
- * does not take @stack_size, as it should only be used in cases
- * in which it is unavoidable.</para></note>
+ * If a thread can not be created (due to resource limits),
+ * @error is set and %NULL is returned.
*
- * Returns: the new #GThread on success
+ * Returns: the new #GThread, or %NULL if an error occurred
*
* Since: 2.32
*/
-GThread*
-g_thread_create_with_stack_size (GThreadFunc func,
- gpointer data,
- gboolean joinable,
- gsize stack_size,
- GError **error)
+GThread *
+g_thread_try_new (const gchar *name,
+ GThreadFunc func,
+ gpointer data,
+ GError **error)
{
- GRealThread* result;
- GError *local_error = NULL;
- g_return_val_if_fail (func, NULL);
-
- result = g_new0 (GRealThread, 1);
-
- result->thread.joinable = joinable;
- result->thread.func = func;
- result->thread.data = data;
- result->private_data = NULL;
- G_LOCK (g_thread);
- g_system_thread_create (g_thread_create_proxy, result,
- stack_size, joinable,
- &result->system_thread, &local_error);
- if (!local_error)
- {
- result->next = g_thread_all_threads;
- g_thread_all_threads = result;
- }
- G_UNLOCK (g_thread);
+ return g_thread_new_internal (name, g_thread_proxy, func, data, 0, error);
+}
- if (local_error)
+GThread *
+g_thread_new_internal (const gchar *name,
+ GThreadFunc proxy,
+ GThreadFunc func,
+ gpointer data,
+ gsize stack_size,
+ GError **error)
+{
+ GRealThread *thread;
+
+ g_return_val_if_fail (func != NULL, NULL);
+
+ G_LOCK (g_thread_new);
+ thread = g_system_thread_new (proxy, stack_size, error);
+ if (thread)
{
- g_propagate_error (error, local_error);
- g_free (result);
- return NULL;
+ thread->ref_count = 2;
+ thread->ours = TRUE;
+ thread->thread.joinable = TRUE;
+ thread->thread.func = func;
+ thread->thread.data = data;
+ thread->name = name;
}
+ G_UNLOCK (g_thread_new);
- return (GThread*) result;
+ return (GThread*) thread;
}
/**
* g_thread_exit:
* @retval: the return value of this thread
*
- * Exits the current thread. If another thread is waiting for that
- * thread using g_thread_join() and the current thread is joinable, the
- * waiting thread will be woken up and get @retval as the return value
- * of g_thread_join(). If the current thread is not joinable, @retval
- * is ignored. Calling
+ * Terminates the current thread.
*
- * |[
- * g_thread_exit (retval);
- * ]|
+ * If another thread is waiting for us using g_thread_join() then the
+ * waiting thread will be woken up and get @retval as the return value
+ * of g_thread_join().
*
- * is equivalent to returning @retval from the function @func, as given
- * to g_thread_create().
+ * Calling <literal>g_thread_exit (retval)</literal> is equivalent to
+ * returning @retval from the function @func, as given to g_thread_new().
*
* <note><para>Never call g_thread_exit() from within a thread of a
* #GThreadPool, as that will mess up the bookkeeping and lead to funny
/**
* g_thread_join:
- * @thread: a #GThread to be waited for
+ * @thread: a #GThread
+ *
+ * Waits until @thread finishes, i.e. the function @func, as
+ * given to g_thread_new(), returns or g_thread_exit() is called.
+ * If @thread has already terminated, then g_thread_join()
+ * returns immediately.
+ *
+ * Any thread can wait for any other thread by calling g_thread_join(),
+ * not just its 'creator'. Calling g_thread_join() from multiple threads
+ * for the same @thread leads to undefined behaviour.
+ *
+ * The value returned by @func or given to g_thread_exit() is
+ * returned by this function.
*
- * Waits until @thread finishes, i.e. the function @func, as given to
- * g_thread_create(), returns or g_thread_exit() is called by @thread.
- * All resources of @thread including the #GThread struct are released.
- * @thread must have been created with @joinable=%TRUE in
- * g_thread_create(). The value returned by @func or given to
- * g_thread_exit() by @thread is returned by this function.
+ * All resources of @thread including the #GThread struct are
+ * released before g_thread_join() returns.
*
* Returns: the return value of the thread
*/
gpointer
-g_thread_join (GThread* thread)
+g_thread_join (GThread *thread)
{
- GRealThread* real = (GRealThread*) thread;
- GRealThread *p, *t;
+ GRealThread *real = (GRealThread*) thread;
gpointer retval;
g_return_val_if_fail (thread, NULL);
- g_return_val_if_fail (thread->joinable, NULL);
- g_return_val_if_fail (!g_system_thread_equal (&real->system_thread, &zero_thread), NULL);
- g_system_thread_join (&real->system_thread);
+ g_system_thread_wait (real);
retval = real->retval;
- G_LOCK (g_thread);
- for (t = g_thread_all_threads, p = NULL; t; p = t, t = t->next)
- {
- if (t == (GRealThread*) thread)
- {
- if (p)
- p->next = t->next;
- else
- g_thread_all_threads = t->next;
- break;
- }
- }
- G_UNLOCK (g_thread);
-
/* Just to make sure, this isn't used any more */
thread->joinable = 0;
- g_system_thread_assign (real->system_thread, zero_thread);
- /* the thread structure for non-joinable threads is freed upon
- * thread end. We free the memory here. This will leave a loose end,
- * if a joinable thread is not joined.
- */
- g_free (thread);
+ g_thread_unref (thread);
return retval;
}
/**
* g_thread_self:
*
- * This functions returns the #GThread corresponding to the calling
- * thread.
+ * This functions returns the #GThread corresponding to the
+ * current thread. Note that this function does not increase
+ * the reference count of the returned object.
*
- * Returns: the current thread
+ * Returns: the #GThread representing the current thread
*/
GThread*
g_thread_self (void)
* This can happen for the main thread and for threads
* that are not created by GLib.
*/
- thread = g_new0 (GRealThread, 1);
- thread->thread.joinable = FALSE; /* This is a safe guess */
- thread->thread.func = NULL;
- thread->thread.data = NULL;
- thread->private_data = NULL;
-
- g_system_thread_self (&thread->system_thread);
+ thread = g_slice_new0 (GRealThread);
+ thread->ref_count = 1;
g_private_set (&g_thread_specific_private, thread);
-
- G_LOCK (g_thread);
- thread->next = g_thread_all_threads;
- g_thread_all_threads = thread;
- G_UNLOCK (g_thread);
- }
-
- return (GThread*)thread;
-}
-
-/**
- * g_thread_foreach:
- * @thread_func: function to call for all #GThread structures
- * @user_data: second argument to @thread_func
- *
- * Call @thread_func on all existing #GThread structures.
- * Note that threads may decide to exit while @thread_func is
- * running, so without intimate knowledge about the lifetime of
- * foreign threads, @thread_func shouldn't access the GThread*
- * pointer passed in as first argument. However, @thread_func will
- * not be called for threads which are known to have exited already.
- *
- * Due to thread lifetime checks, this function has an execution complexity
- * which is quadratic in the number of existing threads.
- *
- * Since: 2.10
- */
-void
-g_thread_foreach (GFunc thread_func,
- gpointer user_data)
-{
- GSList *slist = NULL;
- GRealThread *thread;
- g_return_if_fail (thread_func != NULL);
- /* snapshot the list of threads for iteration */
- G_LOCK (g_thread);
- for (thread = g_thread_all_threads; thread; thread = thread->next)
- slist = g_slist_prepend (slist, thread);
- G_UNLOCK (g_thread);
- /* walk the list, skipping non-existent threads */
- while (slist)
- {
- GSList *node = slist;
- slist = node->next;
- /* check whether the current thread still exists */
- G_LOCK (g_thread);
- for (thread = g_thread_all_threads; thread; thread = thread->next)
- if (thread == node->data)
- break;
- G_UNLOCK (g_thread);
- if (thread)
- thread_func (thread, user_data);
- g_slist_free_1 (node);
}
-}
-
-/* GMutex {{{1 ------------------------------------------------------ */
-/**
- * g_mutex_new:
- *
- * Allocated and initializes a new #GMutex.
- *
- * Returns: a newly allocated #GMutex. Use g_mutex_free() to free
- */
-GMutex *
-g_mutex_new (void)
-{
- GMutex *mutex;
-
- mutex = g_slice_new (GMutex);
- g_mutex_init (mutex);
-
- return mutex;
-}
-
-/**
- * g_mutex_free:
- * @mutex: a #GMutex
- *
- * Destroys a @mutex that has been created with g_mutex_new().
- *
- * Calling g_mutex_free() on a locked mutex may result
- * in undefined behaviour.
- */
-void
-g_mutex_free (GMutex *mutex)
-{
- g_mutex_clear (mutex);
- g_slice_free (GMutex, mutex);
-}
-
-/* GCond {{{1 ------------------------------------------------------ */
-
-/**
- * g_cond_new:
- *
- * Allocates and initializes a new #GCond.
- *
- * Returns: a newly allocated #GCond. Free with g_cond_free()
- */
-GCond *
-g_cond_new (void)
-{
- GCond *cond;
-
- cond = g_slice_new (GCond);
- g_cond_init (cond);
-
- return cond;
-}
-
-/**
- * g_cond_free:
- * @cond: a #GCond
- *
- * Destroys a #GCond that has been created with g_cond_new().
- */
-void
-g_cond_free (GCond *cond)
-{
- g_cond_clear (cond);
- g_slice_free (GCond, cond);
+ return (GThread*) thread;
}
/* Epilogue {{{1 */