From 79b554fe05162550656da3c4e459fb717dc4dadf Mon Sep 17 00:00:00 2001 From: George Hazan Date: Sat, 22 Mar 2014 13:34:19 +0000 Subject: glib inlined into SameTime git-svn-id: http://svn.miranda-ng.org/main/trunk@8685 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c --- protocols/Sametime/src/glib/gthread.c | 2538 +++++++++++++++++++++++++++++++++ 1 file changed, 2538 insertions(+) create mode 100644 protocols/Sametime/src/glib/gthread.c (limited to 'protocols/Sametime/src/glib/gthread.c') diff --git a/protocols/Sametime/src/glib/gthread.c b/protocols/Sametime/src/glib/gthread.c new file mode 100644 index 0000000000..2a00c60a9b --- /dev/null +++ b/protocols/Sametime/src/glib/gthread.c @@ -0,0 +1,2538 @@ +/* GLIB - Library of useful routines for C programming + * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald + * + * gthread.c: MT safety related functions + * Copyright 1998 Sebastian Wilhelmi; University of Karlsruhe + * Owen Taylor + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ + +/* Prelude {{{1 ----------------------------------------------------------- */ + +/* + * Modified by the GLib Team and others 1997-2000. See the AUTHORS + * file for a list of people on the GLib Team. See the ChangeLog + * files for a list of changes. These files are distributed with + * GLib at ftp://ftp.gtk.org/pub/gtk/. + */ + +/* + * MT safe + */ + +/* implement gthread.h's inline functions */ +#define G_IMPLEMENT_INLINES 1 +#define __G_THREAD_C__ + +#include "config.h" + +#include "gthread.h" +#include "gthreadprivate.h" + +#ifdef HAVE_UNISTD_H +#include +#endif + +#ifndef G_OS_WIN32 +#include +#include +#else +#include +#endif /* G_OS_WIN32 */ + +#include + +#include "garray.h" +#include "gslist.h" +#include "gtestutils.h" +#include "gtimer.h" + + +/** + * SECTION: threads + * @title: Threads + * @short_description: thread abstraction; including threads, different + * mutexes, conditions and thread private data + * @see_also: #GThreadPool, #GAsyncQueue + * + * 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. + **/ + +/** + * G_THREADS_IMPL_POSIX: + * + * This macro is defined if POSIX style threads are used. + **/ + +/** + * G_THREADS_ENABLED: + * + * This macro is defined if GLib was compiled with thread support. This + * does not necessarily mean that there is a thread implementation + * available, but it does mean that the infrastructure is in place and + * that once you provide a thread implementation to g_thread_init(), + * GLib will be multi-thread safe. If #G_THREADS_ENABLED is not + * defined, then Glib is not, and cannot be, multi-thread safe. + **/ + +/** + * G_THREADS_IMPL_NONE: + * + * This macro is defined if no thread implementation is used. You can, + * however, provide one to g_thread_init() to make GLib multi-thread + * safe. + **/ + +/* G_LOCK Documentation {{{1 ---------------------------------------------- */ + +/* IMPLEMENTATION NOTE: + * + * G_LOCK_DEFINE and friends are convenience macros defined in + * gthread.h. Their documentation lives here. + */ + +/** + * G_LOCK_DEFINE: + * @name: the name of the lock. + * + * The %G_LOCK_* macros provide a convenient interface to #GStaticMutex + * 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 + * 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 #GStaticMutex. 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 + * give_me_next_number() example using the + * %G_LOCK_* macros: + * + * + * Using the %G_LOCK_* convenience macros + * + * G_LOCK_DEFINE (current_number); + * + * int + * give_me_next_number (void) + * { + * static int current_number = 0; + * int ret_val; + * + * G_LOCK (current_number); + * ret_val = current_number = calc_next_number (current_number); + * G_UNLOCK (current_number); + * + * return ret_val; + * } + * + * + **/ + +/** + * G_LOCK_DEFINE_STATIC: + * @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. + * + * This declares a lock, that is defined with #G_LOCK_DEFINE in another + * module. + **/ + +/** + * G_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. + * @Returns: %TRUE, if the lock could be locked. + * + * Works like g_mutex_trylock(), but for a lock defined with + * #G_LOCK_DEFINE. + **/ + +/** + * G_UNLOCK: + * @name: the name of the lock. + * + * Works like g_mutex_unlock(), but for a lock defined with + * #G_LOCK_DEFINE. + **/ + +/* GThreadError {{{1 ------------------------------------------------------- */ +/** + * GThreadError: + * @G_THREAD_ERROR_AGAIN: a thread couldn't be created due to resource + * shortage. Try again later. + * + * Possible errors of thread related functions. + **/ + +/** + * G_THREAD_ERROR: + * + * The error domain of the GLib thread subsystem. + **/ +GQuark +g_thread_error_quark (void) +{ + return g_quark_from_static_string ("g_thread_error"); +} + +/* Miscellaneous Structures {{{1 ------------------------------------------ */ +/* Keep this in sync with GRealThread in gmain.c! */ +typedef struct _GRealThread GRealThread; +struct _GRealThread +{ + GThread thread; + gpointer private_data; + GRealThread *next; + gpointer retval; + GSystemThread system_thread; +}; + +typedef struct _GStaticPrivateNode GStaticPrivateNode; +struct _GStaticPrivateNode +{ + gpointer data; + GDestroyNotify destroy; +}; + +static void g_thread_cleanup (gpointer data); +static void g_thread_fail (void); +static guint64 gettime (void); + +guint64 (*g_thread_gettime) (void) = gettime; + +/* Global Variables {{{1 -------------------------------------------------- */ + +static GSystemThread zero_thread; /* This is initialized to all zero */ +gboolean g_thread_use_default_impl = TRUE; + +/** + * g_thread_supported: + * @Returns: %TRUE, if the thread system is initialized. + * + * This function returns %TRUE if the thread system is initialized, and + * %FALSE if it is not. + * + * This function is actually a macro. Apart from taking the + * address of it you can however use it as if it was a + * function. + **/ + +/* IMPLEMENTATION NOTE: + * + * g_thread_supported() is just returns g_threads_got_initialized + */ +gboolean g_threads_got_initialized = FALSE; + + +/* Thread Implementation Virtual Function Table {{{1 ---------------------- */ +/* Virtual Function Table Documentation {{{2 ------------------------------ */ +/** + * GThreadFunctions: + * @mutex_new: virtual function pointer for g_mutex_new() + * @mutex_lock: virtual function pointer for g_mutex_lock() + * @mutex_trylock: virtual function pointer for g_mutex_trylock() + * @mutex_unlock: virtual function pointer for g_mutex_unlock() + * @mutex_free: virtual function pointer for g_mutex_free() + * @cond_new: virtual function pointer for g_cond_new() + * @cond_signal: virtual function pointer for g_cond_signal() + * @cond_broadcast: virtual function pointer for g_cond_broadcast() + * @cond_wait: virtual function pointer for g_cond_wait() + * @cond_timed_wait: virtual function pointer for g_cond_timed_wait() + * @cond_free: virtual function pointer for g_cond_free() + * @private_new: virtual function pointer for g_private_new() + * @private_get: virtual function pointer for g_private_get() + * @private_set: virtual function pointer for g_private_set() + * @thread_create: virtual function pointer for g_thread_create() + * @thread_yield: virtual function pointer for g_thread_yield() + * @thread_join: virtual function pointer for g_thread_join() + * @thread_exit: virtual function pointer for g_thread_exit() + * @thread_set_priority: virtual function pointer for + * g_thread_set_priority() + * @thread_self: virtual function pointer for g_thread_self() + * @thread_equal: used internally by recursive mutex locks and by some + * assertion checks + * + * This function table is used by g_thread_init() to initialize the + * thread system. The functions in the table are directly used by their + * g_* prepended counterparts (described in this document). For + * example, if you call g_mutex_new() then mutex_new() from the table + * provided to g_thread_init() will be called. + * + * Do not use this struct unless you know what you are + * doing. + **/ + +/* IMPLEMENTATION NOTE: + * + * g_thread_functions_for_glib_use is a global symbol that gets used by + * most of the "primative" threading calls. g_mutex_lock(), for + * example, is just a macro that calls the appropriate virtual function + * out of this table. + * + * For that reason, all of those macros are documented here. + */ +GThreadFunctions g_thread_functions_for_glib_use = { +/* GMutex Virtual Functions {{{2 ------------------------------------------ */ + +/** + * GMutex: + * + * The #GMutex struct is an opaque data structure to represent a mutex + * (mutual exclusion). It can be used to protect data against shared + * access. Take for example the following function: + * + * + * A function which will not work in a threaded environment + * + * int + * give_me_next_number (void) + * { + * static int current_number = 0; + * + * /* now do a very complicated calculation to calculate the new + * * number, this might for example be a random number generator + * */ + * current_number = calc_next_number (current_number); + * + * return current_number; + * } + * + * + * + * 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: + * + * + * The wrong way to write a thread-safe function + * + * 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; + * } + * + * + * + * 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: + * + * + * A correct thread-safe function + * + * 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; + * } + * + * + * + * #GStaticMutex provides a simpler and safer way of doing this. + * + * If you want to use a mutex, and your code should also work without + * calling g_thread_init() first, then you can not use a #GMutex, as + * g_mutex_new() requires that the thread system be initialized. Use a + * #GStaticMutex instead. + * + * A #GMutex should only be accessed via the following functions. + * + * All of the g_mutex_* functions are + * actually macros. Apart from taking their addresses, you can however + * use them as if they were functions. + **/ + +/** + * g_mutex_new: + * @Returns: a new #GMutex. + * + * Creates a new #GMutex. + * + * This function will abort if g_thread_init() has not been + * called yet. + **/ + (GMutex*(*)())g_thread_fail, + +/** + * g_mutex_lock: + * @mutex: a #GMutex. + * + * Locks @mutex. If @mutex is already locked by another thread, the + * current thread will block until @mutex is unlocked by the other + * thread. + * + * This function can be used even if g_thread_init() has not yet been + * called, and, in that case, will do nothing. + * + * #GMutex is neither guaranteed to be recursive nor to be + * non-recursive, i.e. a thread could deadlock while calling + * g_mutex_lock(), if it already has locked @mutex. Use + * #GStaticRecMutex, if you need recursive mutexes. + **/ + NULL, + +/** + * g_mutex_trylock: + * @mutex: a #GMutex. + * @Returns: %TRUE, if @mutex could be locked. + * + * Tries to lock @mutex. If @mutex is already locked by another thread, + * it immediately returns %FALSE. Otherwise it locks @mutex and returns + * %TRUE. + * + * This function can be used even if g_thread_init() has not yet been + * called, and, in that case, will immediately return %TRUE. + * + * #GMutex is neither guaranteed to be recursive nor to be + * non-recursive, i.e. the return value of g_mutex_trylock() could be + * both %FALSE or %TRUE, if the current thread already has locked + * @mutex. Use #GStaticRecMutex, if you need recursive + * mutexes. + **/ + NULL, + +/** + * g_mutex_unlock: + * @mutex: a #GMutex. + * + * Unlocks @mutex. If another thread is blocked in a g_mutex_lock() + * call for @mutex, it will be woken and can lock @mutex itself. + * + * This function can be used even if g_thread_init() has not yet been + * called, and, in that case, will do nothing. + **/ + NULL, + +/** + * g_mutex_free: + * @mutex: a #GMutex. + * + * Destroys @mutex. + * + * Calling g_mutex_free() on a locked mutex may result in + * undefined behaviour. + **/ + NULL, + +/* GCond Virtual Functions {{{2 ------------------------------------------ */ + +/** + * GCond: + * + * The #GCond struct is an opaque data structure that represents a + * condition. Threads can block on a #GCond if they find a certain + * condition to be false. If other threads change the state of this + * condition they signal the #GCond, and that causes the waiting + * threads to be woken up. + * + * + * + * Using GCond to block a thread until a condition is satisfied + * + * + * GCond* data_cond = NULL; /* Must be initialized somewhere */ + * GMutex* data_mutex = NULL; /* Must be initialized somewhere */ + * gpointer current_data = NULL; + * + * void + * push_data (gpointer data) + * { + * g_mutex_lock (data_mutex); + * current_data = data; + * g_cond_signal (data_cond); + * g_mutex_unlock (data_mutex); + * } + * + * gpointer + * pop_data (void) + * { + * gpointer data; + * + * g_mutex_lock (data_mutex); + * while (!current_data) + * g_cond_wait (data_cond, data_mutex); + * data = current_data; + * current_data = NULL; + * g_mutex_unlock (data_mutex); + * + * return data; + * } + * + * + * + * Whenever a thread calls pop_data() now, it will + * wait until current_data is non-%NULL, i.e. until some other thread + * has called push_data(). + * + * 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. + * + * A #GCond should only be accessed via the following functions. + * + * All of the g_cond_* functions are + * actually macros. Apart from taking their addresses, you can however + * use them as if they were functions. + **/ + +/** + * g_cond_new: + * @Returns: a new #GCond. + * + * Creates a new #GCond. This function will abort, if g_thread_init() + * has not been called yet. + **/ + (GCond*(*)())g_thread_fail, + +/** + * g_cond_signal: + * @cond: a #GCond. + * + * If threads are waiting for @cond, exactly one of them is woken up. + * It is good practice to hold the same lock as the waiting thread + * while calling this function, though not required. + * + * This function can be used even if g_thread_init() has not yet been + * called, and, in that case, will do nothing. + **/ + NULL, + +/** + * g_cond_broadcast: + * @cond: a #GCond. + * + * If threads are waiting for @cond, all of them are woken up. It is + * good practice to lock the same mutex as the waiting threads, while + * calling this function, though not required. + * + * This function can be used even if g_thread_init() has not yet been + * called, and, in that case, will do nothing. + **/ + NULL, + +/** + * g_cond_wait: + * @cond: a #GCond. + * @mutex: a #GMutex, that is currently locked. + * + * Waits until this thread is woken up on @cond. The @mutex is unlocked + * before falling asleep and locked again before resuming. + * + * This function can be used even if g_thread_init() has not yet been + * called, and, in that case, will immediately return. + **/ + NULL, + +/** + * g_cond_timed_wait: + * @cond: a #GCond. + * @mutex: a #GMutex that is currently locked. + * @abs_time: a #GTimeVal, determining the final time. + * @Returns: %TRUE if @cond was signalled, or %FALSE on timeout. + * + * Waits until this thread is woken up on @cond, but not longer than + * until the time specified by @abs_time. The @mutex is unlocked before + * falling asleep and locked again before resuming. + * + * If @abs_time is %NULL, g_cond_timed_wait() acts like g_cond_wait(). + * + * This function can be used even if g_thread_init() has not yet been + * called, and, in that case, will immediately return %TRUE. + * + * To easily calculate @abs_time a combination of g_get_current_time() + * and g_time_val_add() can be used. + **/ + NULL, + +/** + * g_cond_free: + * @cond: a #GCond. + * + * Destroys the #GCond. + **/ + NULL, + +/* GPrivate Virtual Functions {{{2 --------------------------------------- */ + +/** + * GPrivate: + * + * The #GPrivate struct is an opaque data structure to represent a + * thread private data key. Threads can thereby obtain and set a + * pointer which is private to the current thread. Take our + * give_me_next_number() example from + * above. Suppose we don't want current_number to be + * shared between the threads, but instead to be private to each thread. + * This can be done as follows: + * + * + * Using GPrivate for per-thread data + * + * GPrivate* current_number_key = NULL; /* Must be initialized somewhere + * with g_private_new (g_free); */ + * + * int + * give_me_next_number (void) + * { + * int *current_number = g_private_get (current_number_key); + * + * if (!current_number) + * { + * current_number = g_new (int, 1); + * *current_number = 0; + * g_private_set (current_number_key, current_number); + * } + * + * *current_number = calc_next_number (*current_number); + * + * return *current_number; + * } + * + * + * + * Here the pointer belonging to the key + * current_number_key is read. If it is %NULL, it has + * not been set yet. Then get memory for an integer value, assign this + * memory to the pointer and write the pointer back. Now we have an + * integer value that is private to the current thread. + * + * The #GPrivate struct should only be accessed via the following + * functions. + * + * All of the g_private_* functions are + * actually macros. Apart from taking their addresses, you can however + * use them as if they were functions. + **/ + +/** + * g_private_new: + * @destructor: a function to destroy the data keyed to #GPrivate when + * a thread ends. + * @Returns: a new #GPrivate. + * + * Creates a new #GPrivate. If @destructor is non-%NULL, it is a + * pointer to a destructor function. Whenever a thread ends and the + * corresponding pointer keyed to this instance of #GPrivate is + * non-%NULL, the destructor is called with this pointer as the + * argument. + * + * @destructor is used quite differently from @notify in + * g_static_private_set(). + * + * A #GPrivate can not be freed. Reuse it instead, if you + * can, to avoid shortage, or use #GStaticPrivate. + * + * This function will abort if g_thread_init() has not been + * called yet. + **/ + (GPrivate*(*)(GDestroyNotify))g_thread_fail, + +/** + * g_private_get: + * @private_key: a #GPrivate. + * @Returns: the corresponding pointer. + * + * Returns the pointer keyed to @private_key for the current thread. If + * g_private_set() hasn't been called for the current @private_key and + * thread yet, this pointer will be %NULL. + * + * This function can be used even if g_thread_init() has not yet been + * called, and, in that case, will return the value of @private_key + * casted to #gpointer. Note however, that private data set + * before g_thread_init() will + * not be retained after the + * call. Instead, %NULL will be returned in all threads directly after + * g_thread_init(), regardless of any g_private_set() calls issued + * before threading system intialization. + **/ + NULL, + +/** + * g_private_set: + * @private_key: a #GPrivate. + * @data: the new pointer. + * + * Sets the pointer keyed to @private_key for the current thread. + * + * This function can be used even if g_thread_init() has not yet been + * called, and, in that case, will set @private_key to @data casted to + * #GPrivate*. See g_private_get() for resulting caveats. + **/ + NULL, + +/* GThread Virtual Functions {{{2 ---------------------------------------- */ +/** + * GThread: + * + * The #GThread struct represents a running thread. It has three public + * read-only members, but the underlying struct is bigger, so you must + * not copy this struct. + * + * Resources for a joinable thread are not fully released + * until g_thread_join() is called for that thread. + **/ + +/** + * 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(). + **/ + +/** + * GThreadPriority: + * @G_THREAD_PRIORITY_LOW: a priority lower than normal + * @G_THREAD_PRIORITY_NORMAL: the default priority + * @G_THREAD_PRIORITY_HIGH: a priority higher than normal + * @G_THREAD_PRIORITY_URGENT: the highest priority + * + * Specifies the priority of a thread. + * + * It is not guaranteed that threads with different priorities + * really behave accordingly. On some systems (e.g. Linux) there are no + * thread priorities. On other systems (e.g. Solaris) there doesn't + * seem to be different scheduling for different priorities. All in all + * try to avoid being dependent on priorities. + **/ + +/** + * g_thread_create: + * @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. + * @Returns: the new #GThread on success. + * + * This function creates a new thread with the default priority. + * + * 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 can be %NULL to ignore errors, or non-%NULL to report errors. + * The error is set, if and only if the function returns %NULL. + **/ + (void(*)(GThreadFunc, gpointer, gulong, + gboolean, gboolean, GThreadPriority, + gpointer, GError**))g_thread_fail, + +/** + * g_thread_yield: + * + * Gives way to other threads waiting to be scheduled. + * + * This function is often used as a method to make busy wait less evil. + * But in most cases you will encounter, there are better methods to do + * that. So in general you shouldn't use this function. + **/ + NULL, + + NULL, /* thread_join */ + NULL, /* thread_exit */ + NULL, /* thread_set_priority */ + NULL, /* thread_self */ + NULL /* thread_equal */ +}; + +/* Local Data {{{1 -------------------------------------------------------- */ + +static GMutex *g_once_mutex = NULL; +static GCond *g_once_cond = NULL; +static GPrivate *g_thread_specific_private = NULL; +static GRealThread *g_thread_all_threads = NULL; +static GSList *g_thread_free_indeces = NULL; +static GSList* g_once_init_list = NULL; + +G_LOCK_DEFINE_STATIC (g_thread); + +/* Initialisation {{{1 ---------------------------------------------------- */ + +#ifdef G_THREADS_ENABLED +/** + * g_thread_init: + * @vtable: a function table of type #GThreadFunctions, that provides + * the entry points to the thread system to be used. + * + * If you use GLib from more than one thread, you must initialize the + * thread system by calling g_thread_init(). Most of the time you will + * only have to call g_thread_init (NULL). + * + * Do not call g_thread_init() with a non-%NULL parameter unless + * you really know what you are doing. + * + * g_thread_init() must not be called directly or indirectly as a + * callback from GLib. Also no mutexes may be currently locked while + * calling g_thread_init(). + * + * g_thread_init() changes the way in which #GTimer measures + * elapsed time. As a consequence, timers that are running while + * g_thread_init() is called may report unreliable times. + * + * Calling g_thread_init() multiple times is allowed (since version + * 2.24), but nothing happens except for the first call. If the + * argument is non-%NULL on such a call a warning will be printed, but + * otherwise the argument is ignored. + * + * If no thread system is available and @vtable is %NULL or if not all + * elements of @vtable are non-%NULL, then g_thread_init() will abort. + * + * To use g_thread_init() in your program, you have to link with + * the libraries that the command pkg-config --libs + * gthread-2.0 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. + **/ + +/* This must be called only once, before any threads are created. + * It will only be called from g_thread_init() in -lgthread. + */ +void +g_thread_init_glib (void) +{ + /* We let the main thread (the one that calls g_thread_init) inherit + * the static_private data set before calling g_thread_init + */ + GRealThread* main_thread = (GRealThread*) g_thread_self (); + + /* mutex and cond creation works without g_threads_got_initialized */ + g_once_mutex = g_mutex_new (); + g_once_cond = g_cond_new (); + + /* we may only create mutex and cond in here */ + _g_mem_thread_init_noprivate_nomessage (); + + /* setup the basic threading system */ + g_threads_got_initialized = TRUE; + g_thread_specific_private = g_private_new (g_thread_cleanup); + g_private_set (g_thread_specific_private, main_thread); + G_THREAD_UF (thread_self, (&main_thread->system_thread)); + + /* complete memory system initialization, g_private_*() works now */ + _g_slice_thread_init_nomessage (); + + /* accomplish log system initialization to enable messaging */ + _g_messages_thread_init_nomessage (); + + /* we may run full-fledged initializers from here */ + _g_atomic_thread_init (); + _g_convert_thread_init (); + _g_rand_thread_init (); + _g_main_thread_init (); + _g_utils_thread_init (); + _g_futex_thread_init (); +#ifdef G_OS_WIN32 + _g_win32_thread_init (); +#endif +} +#endif /* G_THREADS_ENABLED */ + +/* The following sections implement: GOnce, GStaticMutex, GStaticRecMutex, + * GStaticPrivate, + **/ + +/* GOnce {{{1 ------------------------------------------------------------- */ + +/** + * GOnce: + * @status: the status of the #GOnce + * @retval: the value returned by the call to the function, if @status + * is %G_ONCE_STATUS_READY + * + * A #GOnce struct controls a one-time initialization function. Any + * one-time initialization function must have its own unique #GOnce + * struct. + * + * Since: 2.4 + **/ + +/** + * G_ONCE_INIT: + * + * A #GOnce must be initialized with this macro before it can be used. + * + * + * + * GOnce my_once = G_ONCE_INIT; + * + * + * + * Since: 2.4 + **/ + +/** + * GOnceStatus: + * @G_ONCE_STATUS_NOTCALLED: the function has not been called yet. + * @G_ONCE_STATUS_PROGRESS: the function call is currently in progress. + * @G_ONCE_STATUS_READY: the function has been called. + * + * The possible statuses of a one-time initialization function + * controlled by a #GOnce struct. + * + * Since: 2.4 + **/ + +/** + * g_once: + * @once: a #GOnce structure + * @func: the #GThreadFunc function associated to @once. This function + * is called only once, regardless of the number of times it and + * its associated #GOnce struct are passed to g_once(). + * @arg: data to be passed to @func + * + * The first call to this routine by a process with a given #GOnce + * struct calls @func with the given argument. Thereafter, subsequent + * calls to g_once() with the same #GOnce struct do not call @func + * again, but return the stored result of the first call. On return + * from g_once(), the status of @once will be %G_ONCE_STATUS_READY. + * + * For example, a mutex or a thread-specific data key must be created + * exactly once. In a threaded environment, calling g_once() ensures + * that the initialization is serialized across multiple threads. + * + * Calling g_once() recursively on the same #GOnce struct in + * @func will lead to a deadlock. + * + * + * + * gpointer + * get_debug_flags (void) + * { + * static GOnce my_once = G_ONCE_INIT; + * + * g_once (&my_once, parse_debug_flags, NULL); + * + * return my_once.retval; + * } + * + * + * + * Since: 2.4 + **/ +gpointer +g_once_impl (GOnce *once, + GThreadFunc func, + gpointer arg) +{ + g_mutex_lock (g_once_mutex); + + while (once->status == G_ONCE_STATUS_PROGRESS) + g_cond_wait (g_once_cond, g_once_mutex); + + if (once->status != G_ONCE_STATUS_READY) + { + once->status = G_ONCE_STATUS_PROGRESS; + g_mutex_unlock (g_once_mutex); + + once->retval = func (arg); + + g_mutex_lock (g_once_mutex); + once->status = G_ONCE_STATUS_READY; + g_cond_broadcast (g_once_cond); + } + + g_mutex_unlock (g_once_mutex); + + return once->retval; +} + +/** + * g_once_init_enter: + * @value_location: location of a static initializable variable + * containing 0. + * @Returns: %TRUE if the initialization section should be entered, + * %FALSE and blocks otherwise + * + * Function to be called when starting a critical initialization + * section. The argument @value_location must point to a static + * 0-initialized variable that will be set to a value other than 0 at + * the end of the initialization section. In combination with + * g_once_init_leave() and the unique address @value_location, it can + * be ensured that an initialization section will be executed only once + * during a program's life time, and that concurrent threads are + * blocked until initialization completed. To be used in constructs + * like this: + * + * + * + * static gsize initialization_value = 0; + * + * if (g_once_init_enter (&initialization_value)) + * { + * gsize setup_value = 42; /* initialization code here */ + * + * g_once_init_leave (&initialization_value, setup_value); + * } + * + * /* use initialization_value here */ + * + * + * + * Since: 2.14 + **/ +gboolean +g_once_init_enter_impl (volatile gsize *value_location) +{ + gboolean need_init = FALSE; + g_mutex_lock (g_once_mutex); + if (g_atomic_pointer_get (value_location) == NULL) + { + if (!g_slist_find (g_once_init_list, (void*) value_location)) + { + need_init = TRUE; + g_once_init_list = g_slist_prepend (g_once_init_list, (void*) value_location); + } + else + do + g_cond_wait (g_once_cond, g_once_mutex); + while (g_slist_find (g_once_init_list, (void*) value_location)); + } + g_mutex_unlock (g_once_mutex); + return need_init; +} + +/** + * g_once_init_leave: + * @value_location: location of a static initializable variable + * containing 0. + * @initialization_value: 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 + * other than 0. Sets the variable to the initialization value, and + * releases concurrent threads blocking in g_once_init_enter() on this + * initialization variable. + * + * Since: 2.14 + **/ +void +g_once_init_leave (volatile gsize *value_location, + gsize initialization_value) +{ + g_return_if_fail (g_atomic_pointer_get (value_location) == NULL); + g_return_if_fail (initialization_value != 0); + g_return_if_fail (g_once_init_list != NULL); + + g_atomic_pointer_set ((void**)value_location, (void*) initialization_value); + 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); +} + +/* GStaticMutex {{{1 ------------------------------------------------------ */ + +/** + * GStaticMutex: + * + * A #GStaticMutex works like a #GMutex, but it has one significant + * advantage. It doesn't need to be created at run-time like a #GMutex, + * but can be defined at compile-time. Here is a shorter, easier and + * safer version of our give_me_next_number() + * example: + * + * + * + * Using <structname>GStaticMutex</structname> + * to simplify thread-safe programming + * + * + * int + * give_me_next_number (void) + * { + * static int current_number = 0; + * int ret_val; + * static GStaticMutex mutex = G_STATIC_MUTEX_INIT; + * + * g_static_mutex_lock (&mutex); + * ret_val = current_number = calc_next_number (current_number); + * g_static_mutex_unlock (&mutex); + * + * return ret_val; + * } + * + * + * + * Sometimes you would like to dynamically create a mutex. If you don't + * want to require prior calling to g_thread_init(), because your code + * should also be usable in non-threaded programs, you are not able to + * use g_mutex_new() and thus #GMutex, as that requires a prior call to + * g_thread_init(). In theses cases you can also use a #GStaticMutex. + * It must be initialized with g_static_mutex_init() before using it + * and freed with with g_static_mutex_free() when not needed anymore to + * free up any allocated resources. + * + * Even though #GStaticMutex is not opaque, it should only be used with + * the following functions, as it is defined differently on different + * platforms. + * + * All of the g_static_mutex_* functions apart + * from g_static_mutex_get_mutex can also be used + * even if g_thread_init() has not yet been called. Then they do + * nothing, apart from g_static_mutex_trylock, + * which does nothing but returning %TRUE. + * + * All of the g_static_mutex_* + * functions are actually macros. Apart from taking their addresses, you + * can however use them as if they were functions. + **/ + +/** + * G_STATIC_MUTEX_INIT: + * + * A #GStaticMutex must be initialized with this macro, before it can + * be used. This macro can used be to initialize a variable, but it + * cannot be assigned to a variable. In that case you have to use + * g_static_mutex_init(). + * + * + * + * GStaticMutex my_mutex = G_STATIC_MUTEX_INIT; + * + * + **/ + +/** + * g_static_mutex_init: + * @mutex: a #GStaticMutex to be initialized. + * + * Initializes @mutex. Alternatively you can initialize it with + * #G_STATIC_MUTEX_INIT. + **/ +void +g_static_mutex_init (GStaticMutex *mutex) +{ + static const GStaticMutex init_mutex = G_STATIC_MUTEX_INIT; + + g_return_if_fail (mutex); + + *mutex = init_mutex; +} + +/* IMPLEMENTATION NOTE: + * + * On some platforms a GStaticMutex is actually a normal GMutex stored + * inside of a structure instead of being allocated dynamically. We can + * only do this for platforms on which we know, in advance, how to + * allocate (size) and initialise (value) that memory. + * + * On other platforms, a GStaticMutex is nothing more than a pointer to + * a GMutex. In that case, the first access we make to the static mutex + * must first allocate the normal GMutex and store it into the pointer. + * + * configure.ac writes macros into glibconfig.h to determine if + * g_static_mutex_get_mutex() accesses the sturcture in memory directly + * (on platforms where we are able to do that) or if it ends up here, + * where we may have to allocate the GMutex before returning it. + */ + +/** + * g_static_mutex_get_mutex: + * @mutex: a #GStaticMutex. + * @Returns: the #GMutex corresponding to @mutex. + * + * For some operations (like g_cond_wait()) you must have a #GMutex + * instead of a #GStaticMutex. This function will return the + * corresponding #GMutex for @mutex. + **/ +GMutex * +g_static_mutex_get_mutex_impl (GMutex** mutex) +{ + if (!g_thread_supported ()) + return NULL; + + g_assert (g_once_mutex); + + g_mutex_lock (g_once_mutex); + + if (!(*mutex)) + g_atomic_pointer_set (mutex, g_mutex_new()); + + g_mutex_unlock (g_once_mutex); + + return *mutex; +} + +/* IMPLEMENTATION NOTE: + * + * g_static_mutex_lock(), g_static_mutex_trylock() and + * g_static_mutex_unlock() are all preprocessor macros that wrap the + * corresponding g_mutex_*() function around a call to + * g_static_mutex_get_mutex(). + */ + +/** + * g_static_mutex_lock: + * @mutex: a #GStaticMutex. + * + * Works like g_mutex_lock(), but for a #GStaticMutex. + **/ + +/** + * g_static_mutex_trylock: + * @mutex: a #GStaticMutex. + * @Returns: %TRUE, if the #GStaticMutex could be locked. + * + * Works like g_mutex_trylock(), but for a #GStaticMutex. + **/ + +/** + * g_static_mutex_unlock: + * @mutex: a #GStaticMutex. + * + * Works like g_mutex_unlock(), but for a #GStaticMutex. + **/ + +/** + * g_static_mutex_free: + * @mutex: a #GStaticMutex to be freed. + * + * Releases all resources allocated to @mutex. + * + * You don't have to call this functions for a #GStaticMutex with an + * unbounded lifetime, i.e. objects declared 'static', but if you have + * a #GStaticMutex as a member of a structure and the structure is + * freed, you should also free the #GStaticMutex. + * + * Calling g_static_mutex_free() on a locked mutex may + * result in undefined behaviour. + **/ +void +g_static_mutex_free (GStaticMutex* mutex) +{ + GMutex **runtime_mutex; + + g_return_if_fail (mutex); + + /* The runtime_mutex is the first (or only) member of GStaticMutex, + * see both versions (of glibconfig.h) in configure.ac. Note, that + * this variable is NULL, if g_thread_init() hasn't been called or + * if we're using the default thread implementation and it provides + * static mutexes. */ + runtime_mutex = ((GMutex**)mutex); + + if (*runtime_mutex) + g_mutex_free (*runtime_mutex); + + *runtime_mutex = NULL; +} + +/* ------------------------------------------------------------------------ */ + +/** + * GStaticRecMutex: + * + * A #GStaticRecMutex works like a #GStaticMutex, but it can be locked + * multiple times by one thread. If you enter it n times, you have to + * unlock it n times again to let other threads lock it. An exception + * is the function g_static_rec_mutex_unlock_full(): that allows you to + * unlock a #GStaticRecMutex completely returning the depth, (i.e. the + * number of times this mutex was locked). The depth can later be used + * to restore the state of the #GStaticRecMutex by calling + * g_static_rec_mutex_lock_full(). + * + * Even though #GStaticRecMutex is not opaque, it should only be used + * with the following functions. + * + * All of the g_static_rec_mutex_* functions can + * be used even if g_thread_init() has not been called. Then they do + * nothing, apart from g_static_rec_mutex_trylock, + * which does nothing but returning %TRUE. + **/ + +/** + * G_STATIC_REC_MUTEX_INIT: + * + * A #GStaticRecMutex must be initialized with this macro before it can + * be used. This macro can used be to initialize a variable, but it + * cannot be assigned to a variable. In that case you have to use + * g_static_rec_mutex_init(). + * + * + * + * GStaticRecMutex my_mutex = G_STATIC_REC_MUTEX_INIT; + * + + **/ + +/** + * g_static_rec_mutex_init: + * @mutex: a #GStaticRecMutex to be initialized. + * + * A #GStaticRecMutex must be initialized with this function before it + * can be used. Alternatively you can initialize it with + * #G_STATIC_REC_MUTEX_INIT. + **/ +void +g_static_rec_mutex_init (GStaticRecMutex *mutex) +{ + static const GStaticRecMutex init_mutex = G_STATIC_REC_MUTEX_INIT; + + g_return_if_fail (mutex); + + *mutex = init_mutex; +} + +/** + * g_static_rec_mutex_lock: + * @mutex: a #GStaticRecMutex to 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. + **/ +void +g_static_rec_mutex_lock (GStaticRecMutex* mutex) +{ + GSystemThread self; + + g_return_if_fail (mutex); + + if (!g_thread_supported ()) + return; + + G_THREAD_UF (thread_self, (&self)); + + if (g_system_thread_equal (self, mutex->owner)) + { + mutex->depth++; + return; + } + g_static_mutex_lock (&mutex->mutex); + g_system_thread_assign (mutex->owner, self); + mutex->depth = 1; +} + +/** + * g_static_rec_mutex_trylock: + * @mutex: a #GStaticRecMutex to lock. + * @Returns: %TRUE, if @mutex could be locked. + * + * 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. + **/ +gboolean +g_static_rec_mutex_trylock (GStaticRecMutex* mutex) +{ + GSystemThread self; + + g_return_val_if_fail (mutex, FALSE); + + if (!g_thread_supported ()) + return TRUE; + + G_THREAD_UF (thread_self, (&self)); + + if (g_system_thread_equal (self, mutex->owner)) + { + mutex->depth++; + return TRUE; + } + + if (!g_static_mutex_trylock (&mutex->mutex)) + return FALSE; + + g_system_thread_assign (mutex->owner, self); + mutex->depth = 1; + return TRUE; +} + +/** + * g_static_rec_mutex_unlock: + * @mutex: a #GStaticRecMutex to 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. + **/ +void +g_static_rec_mutex_unlock (GStaticRecMutex* mutex) +{ + g_return_if_fail (mutex); + + if (!g_thread_supported ()) + return; + + if (mutex->depth > 1) + { + mutex->depth--; + return; + } + g_system_thread_assign (mutex->owner, zero_thread); + g_static_mutex_unlock (&mutex->mutex); +} + +/** + * g_static_rec_mutex_lock_full: + * @mutex: a #GStaticRecMutex to lock. + * @depth: number of times this mutex has to be unlocked to be + * completely unlocked. + * + * Works like calling g_static_rec_mutex_lock() for @mutex @depth times. + **/ +void +g_static_rec_mutex_lock_full (GStaticRecMutex *mutex, + guint depth) +{ + GSystemThread self; + g_return_if_fail (mutex); + + if (!g_thread_supported ()) + return; + + if (depth == 0) + return; + + G_THREAD_UF (thread_self, (&self)); + + if (g_system_thread_equal (self, mutex->owner)) + { + mutex->depth += depth; + return; + } + g_static_mutex_lock (&mutex->mutex); + g_system_thread_assign (mutex->owner, self); + mutex->depth = depth; +} + +/** + * g_static_rec_mutex_unlock_full: + * @mutex: a #GStaticRecMutex to completely unlock. + * @Returns: number of times @mutex has been locked by the current + * thread. + * + * 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. + **/ +guint +g_static_rec_mutex_unlock_full (GStaticRecMutex *mutex) +{ + guint depth; + + g_return_val_if_fail (mutex, 0); + + if (!g_thread_supported ()) + return 1; + + depth = mutex->depth; + + g_system_thread_assign (mutex->owner, zero_thread); + mutex->depth = 0; + g_static_mutex_unlock (&mutex->mutex); + + return depth; +} + +/** + * g_static_rec_mutex_free: + * @mutex: a #GStaticRecMutex to be freed. + * + * 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. + **/ +void +g_static_rec_mutex_free (GStaticRecMutex *mutex) +{ + g_return_if_fail (mutex); + + g_static_mutex_free (&mutex->mutex); +} + +/* GStaticPrivate {{{1 ---------------------------------------------------- */ + +/** + * 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 give_me_next_number() example with + * #GStaticPrivate: + * + * + * Using GStaticPrivate for per-thread data + * + * 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; + * } + * + * + **/ + +/** + * 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; +} + +/** + * g_static_private_get: + * @private_key: a #GStaticPrivate. + * @Returns: the corresponding pointer. + * + * Works like g_private_get() only for a #GStaticPrivate. + * + * This function works even if g_thread_init() has not yet been called. + **/ +gpointer +g_static_private_get (GStaticPrivate *private_key) +{ + GRealThread *self = (GRealThread*) g_thread_self (); + GArray *array; + + array = self->private_data; + if (!array) + return NULL; + + if (!private_key->index) + return NULL; + else if (private_key->index <= array->len) + return g_array_index (array, GStaticPrivateNode, + private_key->index - 1).data; + else + return NULL; +} + +/** + * 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(). + * + * @notify is used quite differently from @destructor in + * g_private_new(). + **/ +void +g_static_private_set (GStaticPrivate *private_key, + gpointer data, + GDestroyNotify notify) +{ + GRealThread *self = (GRealThread*) g_thread_self (); + GArray *array; + static guint next_index = 0; + GStaticPrivateNode *node; + + array = self->private_data; + if (!array) + { + array = g_array_new (FALSE, TRUE, sizeof (GStaticPrivateNode)); + self->private_data = array; + } + + if (!private_key->index) + { + G_LOCK (g_thread); + + if (!private_key->index) + { + if (g_thread_free_indeces) + { + private_key->index = + GPOINTER_TO_UINT (g_thread_free_indeces->data); + g_thread_free_indeces = + g_slist_delete_link (g_thread_free_indeces, + g_thread_free_indeces); + } + else + private_key->index = ++next_index; + } + + G_UNLOCK (g_thread); + } + + 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) + { + gpointer ddata = node->data; + GDestroyNotify ddestroy = node->destroy; + + node->data = data; + node->destroy = notify; + + ddestroy (ddata); + } + else + { + node->data = data; + node->destroy = notify; + } +} + +/** + * 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; + GRealThread *thread; + + if (!idx) + return; + + private_key->index = 0; + + G_LOCK (g_thread); + + thread = g_thread_all_threads; + while (thread) + { + GArray *array = thread->private_data; + thread = thread->next; + + if (array && idx <= array->len) + { + GStaticPrivateNode *node = &g_array_index (array, + GStaticPrivateNode, + idx - 1); + gpointer ddata = node->data; + GDestroyNotify ddestroy = node->destroy; + + node->data = NULL; + node->destroy = NULL; + + if (ddestroy) + { + G_UNLOCK (g_thread); + ddestroy (ddata); + G_LOCK (g_thread); + } + } + } + g_thread_free_indeces = g_slist_prepend (g_thread_free_indeces, + GUINT_TO_POINTER (idx)); + G_UNLOCK (g_thread); +} + +/* GThread Extra Functions {{{1 ------------------------------------------- */ +static void +g_thread_cleanup (gpointer data) +{ + if (data) + { + GRealThread* thread = data; + if (thread->private_data) + { + GArray* array = thread->private_data; + 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); + } + } +} + +static void +g_thread_fail (void) +{ + g_error ("The thread system is not yet initialized."); +} + +#define G_NSEC_PER_SEC 1000000000 + +static guint64 +gettime (void) +{ +#ifdef G_OS_WIN32 + guint64 v; + + /* Returns 100s of nanoseconds since start of 1601 */ + GetSystemTimeAsFileTime ((FILETIME *)&v); + + /* Offset to Unix epoch */ + v -= G_GINT64_CONSTANT (116444736000000000); + /* Convert to nanoseconds */ + v *= 100; + + return v; +#else + struct timeval tv; + + gettimeofday (&tv, NULL); + + return (guint64) tv.tv_sec * G_NSEC_PER_SEC + tv.tv_usec * (G_NSEC_PER_SEC / G_USEC_PER_SEC); +#endif +} + +static gpointer +g_thread_create_proxy (gpointer data) +{ + GRealThread* thread = data; + + g_assert (data); + + /* 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. */ + G_LOCK (g_thread); + G_UNLOCK (g_thread); + + thread->retval = thread->thread.func (thread->thread.data); + + return NULL; +} + +/** + * g_thread_create_full: + * @func: a function to execute in the new thread. + * @data: an argument to supply to the new thread. + * @stack_size: a stack size for the new thread. + * @joinable: should this thread be joinable? + * @bound: should this thread be bound to a system thread? + * @priority: a priority for the thread. + * @error: return location for error. + * @Returns: the new #GThread on success. + * + * This function creates a new thread with the priority @priority. 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. If @bound is %TRUE, this thread will be + * scheduled in the system scope, otherwise the implementation is free + * to do scheduling in the process scope. The first variant is more + * expensive resource-wise, but generally faster. On some systems (e.g. + * Linux) all threads are bound. + * + * The new thread executes the function @func with the argument @data. + * If the thread was created successfully, it is returned. + * + * @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. + * + * It is not guaranteed that threads with different priorities + * really behave accordingly. On some systems (e.g. Linux) there are no + * thread priorities. On other systems (e.g. Solaris) there doesn't + * seem to be different scheduling for different priorities. All in all + * try to avoid being dependent on priorities. Use + * %G_THREAD_PRIORITY_NORMAL here as a default. + * + * Only use g_thread_create_full() if you really can't use + * g_thread_create() instead. g_thread_create() does not take + * @stack_size, @bound, and @priority as arguments, as they should only + * be used in cases in which it is unavoidable. + **/ +GThread* +g_thread_create_full (GThreadFunc func, + gpointer data, + gulong stack_size, + gboolean joinable, + gboolean bound, + GThreadPriority priority, + GError **error) +{ + GRealThread* result; + GError *local_error = NULL; + g_return_val_if_fail (func, NULL); + g_return_val_if_fail (priority >= G_THREAD_PRIORITY_LOW, NULL); + g_return_val_if_fail (priority <= G_THREAD_PRIORITY_URGENT, NULL); + + result = g_new0 (GRealThread, 1); + + result->thread.joinable = joinable; + result->thread.priority = priority; + result->thread.func = func; + result->thread.data = data; + result->private_data = NULL; + G_LOCK (g_thread); + G_THREAD_UF (thread_create, (g_thread_create_proxy, result, + stack_size, joinable, bound, priority, + &result->system_thread, &local_error)); + if (!local_error) + { + result->next = g_thread_all_threads; + g_thread_all_threads = result; + } + G_UNLOCK (g_thread); + + if (local_error) + { + g_propagate_error (error, local_error); + g_free (result); + return NULL; + } + + return (GThread*) result; +} + +/** + * 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 + * + * + * + * g_thread_exit (retval); + * + * + * + * is equivalent to returning @retval from the function @func, as given + * to g_thread_create(). + * + * Never call g_thread_exit() from within a thread of a + * #GThreadPool, as that will mess up the bookkeeping and lead to funny + * and unwanted results. + **/ +void +g_thread_exit (gpointer retval) +{ + GRealThread* real = (GRealThread*) g_thread_self (); + real->retval = retval; + G_THREAD_CF (thread_exit, (void)0, ()); +} + +/** + * g_thread_join: + * @thread: a #GThread to be waited for. + * @Returns: the return value of the thread. + * + * 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. + **/ +gpointer +g_thread_join (GThread* thread) +{ + GRealThread* real = (GRealThread*) thread; + GRealThread *p, *t; + 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_THREAD_UF (thread_join, (&real->system_thread)); + + 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); + + return retval; +} + +/** + * g_thread_set_priority: + * @thread: a #GThread. + * @priority: a new priority for @thread. + * + * Changes the priority of @thread to @priority. + * + * It is not guaranteed that threads with different + * priorities really behave accordingly. On some systems (e.g. Linux) + * there are no thread priorities. On other systems (e.g. Solaris) there + * doesn't seem to be different scheduling for different priorities. All + * in all try to avoid being dependent on priorities. + **/ +void +g_thread_set_priority (GThread* thread, + GThreadPriority priority) +{ + GRealThread* real = (GRealThread*) thread; + + g_return_if_fail (thread); + g_return_if_fail (!g_system_thread_equal (real->system_thread, zero_thread)); + g_return_if_fail (priority >= G_THREAD_PRIORITY_LOW); + g_return_if_fail (priority <= G_THREAD_PRIORITY_URGENT); + + thread->priority = priority; + + G_THREAD_CF (thread_set_priority, (void)0, + (&real->system_thread, priority)); +} + +/** + * g_thread_self: + * @Returns: the current thread. + * + * This functions returns the #GThread corresponding to the calling + * thread. + **/ +GThread* +g_thread_self (void) +{ + GRealThread* thread = g_private_get (g_thread_specific_private); + + if (!thread) + { + /* If no thread data is available, provide and set one. 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 save guess */ + thread->thread.priority = G_THREAD_PRIORITY_NORMAL; /* This is + just a guess */ + thread->thread.func = NULL; + thread->thread.data = NULL; + thread->private_data = NULL; + + if (g_thread_supported ()) + G_THREAD_UF (thread_self, (&thread->system_thread)); + + 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; +} + +/* GStaticRWLock {{{1 ----------------------------------------------------- */ + +/** + * GStaticRWLock: + * + * The #GStaticRWLock struct represents a read-write lock. A read-write + * lock can be used for protecting data that some portions of code only + * read from, while others also write. In such situations it is + * desirable that several readers can read at once, whereas of course + * only one writer may write at a time. Take a look at the following + * example: + * + * + * An array with access functions + * + * GStaticRWLock rwlock = G_STATIC_RW_LOCK_INIT; + * GPtrArray *array; + * + * gpointer + * my_array_get (guint index) + * { + * gpointer retval = NULL; + * + * if (!array) + * return NULL; + * + * g_static_rw_lock_reader_lock (&rwlock); + * if (index < array->len) + * retval = g_ptr_array_index (array, index); + * g_static_rw_lock_reader_unlock (&rwlock); + * + * return retval; + * } + * + * void + * my_array_set (guint index, gpointer data) + * { + * g_static_rw_lock_writer_lock (&rwlock); + * + * if (!array) + * array = g_ptr_array_new (); + * + * if (index >= array->len) + * g_ptr_array_set_size (array, index+1); + * g_ptr_array_index (array, index) = data; + * + * g_static_rw_lock_writer_unlock (&rwlock); + * } + * + * + * + * This example shows an array which can be accessed by many readers + * (the my_array_get() function) simultaneously, + * whereas the writers (the my_array_set() + * function) will only be allowed once at a time and only if no readers + * currently access the array. This is because of the potentially + * dangerous resizing of the array. Using these functions is fully + * multi-thread safe now. + * + * Most of the time, writers should have precedence over readers. That + * means, for this implementation, that as soon as a writer wants to + * lock the data, no other reader is allowed to lock the data, whereas, + * of course, the readers that already have locked the data are allowed + * to finish their operation. As soon as the last reader unlocks the + * data, the writer will lock it. + * + * Even though #GStaticRWLock is not opaque, it should only be used + * with the following functions. + * + * All of the g_static_rw_lock_* functions can be + * used even if g_thread_init() has not been called. Then they do + * nothing, apart from g_static_rw_lock_*_trylock, + * which does nothing but returning %TRUE. + * + * A read-write lock has a higher overhead than a mutex. For + * example, both g_static_rw_lock_reader_lock() and + * g_static_rw_lock_reader_unlock() have to lock and unlock a + * #GStaticMutex, so it takes at least twice the time to lock and unlock + * a #GStaticRWLock that it does to lock and unlock a #GStaticMutex. So + * only data structures that are accessed by multiple readers, and which + * keep the lock for a considerable time justify a #GStaticRWLock. The + * above example most probably would fare better with a + * #GStaticMutex. + **/ + +/** + * G_STATIC_RW_LOCK_INIT: + * + * A #GStaticRWLock must be initialized with this macro before it can + * be used. This macro can used be to initialize a variable, but it + * cannot be assigned to a variable. In that case you have to use + * g_static_rw_lock_init(). + * + * + * + * GStaticRWLock my_lock = G_STATIC_RW_LOCK_INIT; + * + * + **/ + +/** + * g_static_rw_lock_init: + * @lock: a #GStaticRWLock to be initialized. + * + * A #GStaticRWLock must be initialized with this function before it + * can be used. Alternatively you can initialize it with + * #G_STATIC_RW_LOCK_INIT. + **/ +void +g_static_rw_lock_init (GStaticRWLock* lock) +{ + static const GStaticRWLock init_lock = G_STATIC_RW_LOCK_INIT; + + g_return_if_fail (lock); + + *lock = init_lock; +} + +inline static void +g_static_rw_lock_wait (GCond** cond, GStaticMutex* mutex) +{ + if (!*cond) + *cond = g_cond_new (); + g_cond_wait (*cond, g_static_mutex_get_mutex (mutex)); +} + +inline static void +g_static_rw_lock_signal (GStaticRWLock* lock) +{ + if (lock->want_to_write && lock->write_cond) + g_cond_signal (lock->write_cond); + else if (lock->want_to_read && lock->read_cond) + g_cond_broadcast (lock->read_cond); +} + +/** + * g_static_rw_lock_reader_lock: + * @lock: a #GStaticRWLock to lock for reading. + * + * Locks @lock for reading. There may be unlimited concurrent locks for + * reading of a #GStaticRWLock at the same time. If @lock is already + * locked for writing by another thread or if another thread is already + * waiting to lock @lock for writing, this function will block until + * @lock is unlocked by the other writing thread and no other writing + * threads want to lock @lock. This lock has to be unlocked by + * g_static_rw_lock_reader_unlock(). + * + * #GStaticRWLock is not recursive. It might seem to be possible to + * recursively lock for reading, but that can result in a deadlock, due + * to writer preference. + **/ +void +g_static_rw_lock_reader_lock (GStaticRWLock* lock) +{ + g_return_if_fail (lock); + + if (!g_threads_got_initialized) + return; + + g_static_mutex_lock (&lock->mutex); + lock->want_to_read++; + while (lock->have_writer || lock->want_to_write) + g_static_rw_lock_wait (&lock->read_cond, &lock->mutex); + lock->want_to_read--; + lock->read_counter++; + g_static_mutex_unlock (&lock->mutex); +} + +/** + * g_static_rw_lock_reader_trylock: + * @lock: a #GStaticRWLock to lock for reading. + * @Returns: %TRUE, if @lock could be locked for reading. + * + * Tries to lock @lock for reading. If @lock is already locked for + * writing by another thread or if another thread is already waiting to + * lock @lock for writing, immediately returns %FALSE. Otherwise locks + * @lock for reading and returns %TRUE. This lock has to be unlocked by + * g_static_rw_lock_reader_unlock(). + **/ +gboolean +g_static_rw_lock_reader_trylock (GStaticRWLock* lock) +{ + gboolean ret_val = FALSE; + + g_return_val_if_fail (lock, FALSE); + + if (!g_threads_got_initialized) + return TRUE; + + g_static_mutex_lock (&lock->mutex); + if (!lock->have_writer && !lock->want_to_write) + { + lock->read_counter++; + ret_val = TRUE; + } + g_static_mutex_unlock (&lock->mutex); + return ret_val; +} + +/** + * g_static_rw_lock_reader_unlock: + * @lock: a #GStaticRWLock to unlock after reading. + * + * Unlocks @lock. If a thread waits to lock @lock for writing and all + * locks for reading have been unlocked, the waiting thread is woken up + * and can lock @lock for writing. + **/ +void +g_static_rw_lock_reader_unlock (GStaticRWLock* lock) +{ + g_return_if_fail (lock); + + if (!g_threads_got_initialized) + return; + + g_static_mutex_lock (&lock->mutex); + lock->read_counter--; + if (lock->read_counter == 0) + g_static_rw_lock_signal (lock); + g_static_mutex_unlock (&lock->mutex); +} + +/** + * g_static_rw_lock_writer_lock: + * @lock: a #GStaticRWLock to lock for writing. + * + * Locks @lock for writing. If @lock is already locked for writing or + * reading by other threads, this function will block until @lock is + * completely unlocked and then lock @lock for writing. While this + * functions waits to lock @lock, no other thread can lock @lock for + * reading. When @lock is locked for writing, no other thread can lock + * @lock (neither for reading nor writing). This lock has to be + * unlocked by g_static_rw_lock_writer_unlock(). + **/ +void +g_static_rw_lock_writer_lock (GStaticRWLock* lock) +{ + g_return_if_fail (lock); + + if (!g_threads_got_initialized) + return; + + g_static_mutex_lock (&lock->mutex); + lock->want_to_write++; + while (lock->have_writer || lock->read_counter) + g_static_rw_lock_wait (&lock->write_cond, &lock->mutex); + lock->want_to_write--; + lock->have_writer = TRUE; + g_static_mutex_unlock (&lock->mutex); +} + +/** + * g_static_rw_lock_writer_trylock: + * @lock: a #GStaticRWLock to lock for writing. + * @Returns: %TRUE, if @lock could be locked for writing. + * + * Tries to lock @lock for writing. If @lock is already locked (for + * either reading or writing) by another thread, it immediately returns + * %FALSE. Otherwise it locks @lock for writing and returns %TRUE. This + * lock has to be unlocked by g_static_rw_lock_writer_unlock(). + **/ +gboolean +g_static_rw_lock_writer_trylock (GStaticRWLock* lock) +{ + gboolean ret_val = FALSE; + + g_return_val_if_fail (lock, FALSE); + + if (!g_threads_got_initialized) + return TRUE; + + g_static_mutex_lock (&lock->mutex); + if (!lock->have_writer && !lock->read_counter) + { + lock->have_writer = TRUE; + ret_val = TRUE; + } + g_static_mutex_unlock (&lock->mutex); + return ret_val; +} + +/** + * g_static_rw_lock_writer_unlock: + * @lock: a #GStaticRWLock to unlock after writing. + * + * Unlocks @lock. If a thread is waiting to lock @lock for writing and + * all locks for reading have been unlocked, the waiting thread is + * woken up and can lock @lock for writing. If no thread is waiting to + * lock @lock for writing, and some thread or threads are waiting to + * lock @lock for reading, the waiting threads are woken up and can + * lock @lock for reading. + **/ +void +g_static_rw_lock_writer_unlock (GStaticRWLock* lock) +{ + g_return_if_fail (lock); + + if (!g_threads_got_initialized) + return; + + g_static_mutex_lock (&lock->mutex); + lock->have_writer = FALSE; + g_static_rw_lock_signal (lock); + g_static_mutex_unlock (&lock->mutex); +} + +/** + * g_static_rw_lock_free: + * @lock: a #GStaticRWLock to be freed. + * + * Releases all resources allocated to @lock. + * + * You don't have to call this functions for a #GStaticRWLock with an + * unbounded lifetime, i.e. objects declared 'static', but if you have + * a #GStaticRWLock as a member of a structure, and the structure is + * freed, you should also free the #GStaticRWLock. + **/ +void +g_static_rw_lock_free (GStaticRWLock* lock) +{ + g_return_if_fail (lock); + + if (lock->read_cond) + { + g_cond_free (lock->read_cond); + lock->read_cond = NULL; + } + if (lock->write_cond) + { + g_cond_free (lock->write_cond); + lock->write_cond = NULL; + } + g_static_mutex_free (&lock->mutex); +} + +/* Unsorted {{{1 ---------------------------------------------------------- */ + +/** + * 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-existant 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); + } +} + +/** + * 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 () +{ + return g_thread_supported (); +} -- cgit v1.2.3