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core.thread.threadbase

The threadbase module provides OS-independent code for thread storage and management.
License:
Distributed under the Boost Software License 1.0. (See accompanying file LICENSE)
Authors:
Sean Kelly, Walter Bright, Alex Rønne Petersen, Martin Nowak
class ThreadException: object.Exception;
Base class for thread exceptions.
class ThreadError: object.Error;
Base class for thread errors to be used for function inside GC when allocations are unavailable.
abstract class ThreadBase;
pure nothrow @nogc @safe this(void function() fn, size_t sz = 0);
package nothrow @nogc bool destructBeforeDtor();
Cleans up any remaining resources used by this object.
abstract Throwable join(bool rethrow = true);
Waits for this thread to complete. If the thread terminated as the result of an unhandled exception, this exception will be rethrown.
Parameters:
bool rethrow Rethrow any unhandled exception which may have caused this thread to terminate.
Throws:
ThreadException if the operation fails. Any exception not handled by the joined thread.
Returns:
Any exception not handled by this thread if rethrow = false, null otherwise.
final @nogc @property @safe ThreadID id();
Gets the OS identifier for this thread.
Returns:
If the thread hasn't been started yet, returns ThreadID.init. Otherwise, returns the result of GetCurrentThreadId on Windows, and pthread_self on POSIX.
The value is unique for the current process.
final @nogc @property @safe string name();
Gets the user-readable label for this thread.
Returns:
The name of this thread.
final @nogc @property @safe void name(string val);
Sets the user-readable label for this thread.
Parameters:
string val The new name of this thread.
final @nogc @property @safe bool isDaemon();
Gets the daemon status for this thread. While the runtime will wait for all normal threads to complete before tearing down the process, daemon threads are effectively ignored and thus will not prevent the process from terminating. In effect, daemon threads will be terminated automatically by the OS when the process exits.
Returns:
true if this is a daemon thread.
final @nogc @property @safe void isDaemon(bool val);
Sets the daemon status for this thread. While the runtime will wait for all normal threads to complete before tearing down the process, daemon threads are effectively ignored and thus will not prevent the process from terminating. In effect, daemon threads will be terminated automatically by the OS when the process exits.
Parameters:
bool val The new daemon status for this thread.
final nothrow @nogc @property bool isMainThread();
Tests whether this thread is the main thread, i.e. the thread that initialized the runtime
Returns:
true if the thread is the main thread
nothrow @nogc @property bool isRunning();
Tests whether this thread is running.
Returns:
true if the thread is running, false if not.
static nothrow @nogc @safe ThreadBase getThis();
Provides a reference to the calling thread.
Returns:
The thread object representing the calling thread. The result of deleting this object is undefined. If the current thread is not attached to the runtime, a null reference is returned.
static ThreadBase[] getAll();
Provides a list of all threads currently being tracked by the system. Note that threads in the returned array might no longer run (see ThreadBase.isRunning).
Returns:
An array containing references to all threads currently being tracked by the system. The result of deleting any contained objects is undefined.
static int opApply(scope int delegate(ref ThreadBase) dg);
Operates on all threads currently being tracked by the system. The result of deleting any Thread object is undefined. Note that threads passed to the callback might no longer run (see ThreadBase.isRunning).
Parameters:
int delegate(ref ThreadBase) dg The supplied code as a delegate.
Returns:
Zero if all elemented are visited, nonzero if not.
package pure nothrow @nogc @safe this(size_t sz = 0);
package static nothrow @nogc void setThis(ThreadBase t);
package(core.thread) final nothrow @nogc void pushContext(StackContext* c);
package(core.thread) static nothrow @nogc @property Mutex slock();
package(core.thread) static nothrow @nogc void add(StackContext* c);
package(core.thread) static nothrow @nogc void add(ThreadBase t, bool rmAboutToStart = true);
@nogc void thread_term_tpl(ThreadT, MainThreadStore)(ref MainThreadStore _mainThreadStore);
Terminates the thread module. No other thread routine may be called afterwards.
nothrow @nogc bool thread_isMainThread();
ThreadT thread_attachThis_tpl(ThreadT)();
Registers the calling thread for use with the D Runtime. If this routine is called for a thread which is already registered, no action is performed.

NOTE This routine does not run thread-local static constructors when called. If full functionality as a D thread is desired, the following function must be called after thread_attachThis:

extern (C) void rt_moduleTlsCtor();

nothrow @nogc void thread_detachThis();
Deregisters the calling thread from use with the runtime. If this routine is called for a thread which is not registered, the result is undefined.

NOTE This routine does not run thread-local static destructors when called. If full functionality as a D thread is desired, the following function must be called after thread_detachThis, particularly if the thread is being detached at some indeterminate time before program termination:

extern(C) void rt_moduleTlsDtor();

void thread_detachByAddr(ThreadID addr);

nothrow @nogc void thread_detachInstance(ThreadBase t);
Deregisters the given thread from use with the runtime. If this routine is called for a thread which is not registered, the result is undefined.

NOTE This routine does not run thread-local static destructors when called. If full functionality as a D thread is desired, the following function must be called by the detached thread, particularly if the thread is being detached at some indeterminate time before program termination:

extern(C) void rt_moduleTlsDtor();

static ThreadBase thread_findByAddr(ThreadID addr);
Search the list of all threads for a thread with the given thread identifier.
Parameters:
ThreadID addr The thread identifier to search for.
Returns:
The thread object associated with the thread identifier, null if not found.
nothrow @nogc void thread_setThis(ThreadBase t);
Sets the current thread to a specific reference. Only to be used when dealing with externally-created threads (in e.g. C code). The primary use of this function is when ThreadBase.getThis() must return a sensible value in, for example, TLS destructors. In other words, don't touch this unless you know what you're doing.
Parameters:
ThreadBase t A reference to the current thread. May be null.
void thread_joinAll();
Joins all non-daemon threads that are currently running. This is done by performing successive scans through the thread list until a scan consists of only daemon threads.
nothrow void thread_resumeAll();
Resume all threads but the calling thread for "stop the world" garbage collection runs. This function must be called once for each preceding call to thread_suspendAll before the threads are actually resumed.

In This routine must be preceded by a call to thread_suspendAll.

Throws:
ThreadError if the resume operation fails for a running thread.
enum ScanType: int;
Indicates the kind of scan being performed by thread_scanAllType.
stack
The stack and/or registers are being scanned.
tls
TLS data is being scanned.
alias ScanAllThreadsFn = void delegate(void*, void*) nothrow;

alias ScanAllThreadsTypeFn = void delegate(ScanType, void*, void*) nothrow;
The scanning function.
nothrow void thread_scanAllType(scope ScanAllThreadsTypeFn scan);
The main entry point for garbage collection. The supplied delegate will be passed ranges representing both stack and register values.
Parameters:
ScanAllThreadsTypeFn scan The scanner function. It should scan from p1 through p2 - 1.

In This routine must be preceded by a call to thread_suspendAll.

nothrow void thread_scanAll(scope ScanAllThreadsFn scan);
The main entry point for garbage collection. The supplied delegate will be passed ranges representing both stack and register values.
Parameters:
ScanAllThreadsFn scan The scanner function. It should scan from p1 through p2 - 1.

In This routine must be preceded by a call to thread_suspendAll.

@nogc void thread_enterCriticalRegion();
Signals that the code following this call is a critical region. Any code in this region must finish running before the calling thread can be suspended by a call to thread_suspendAll.
This function is, in particular, meant to help maintain garbage collector invariants when a lock is not used.
A critical region is exited with thread_exitCriticalRegion.
Warning: Using critical regions is extremely error-prone. For instance, using locks inside a critical region can easily result in a deadlock when another thread holding the lock already got suspended.
The term and concept of a 'critical region' comes from Mono's SGen garbage collector.

In The calling thread must be attached to the runtime.

@nogc void thread_exitCriticalRegion();
Signals that the calling thread is no longer in a critical region. Following a call to this function, the thread can once again be suspended.

In The calling thread must be attached to the runtime.

@nogc bool thread_inCriticalRegion();
Returns true if the current thread is in a critical region; otherwise, false.

In The calling thread must be attached to the runtime.

package nothrow @nogc void onThreadError(string msg);
A callback for thread errors in D during collections. Since an allocation is not possible a preallocated ThreadError will be used as the Error instance
Returns:
never returns
Throws:
ThreadError.
enum IsMarked: int;
Indicates whether an address has been marked by the GC.
no
Address is not marked.
yes
Address is marked.
unknown
Address is not managed by the GC.
alias IsMarkedDg = int delegate(void* addr) nothrow;
The isMarked callback function.
nothrow void thread_processGCMarks(scope IsMarkedDg isMarked);
This routine allows the runtime to process any special per-thread handling for the GC. This is needed for taking into account any memory that is referenced by non-scanned pointers but is about to be freed. That currently means the array append cache.
Parameters:
IsMarkedDg isMarked The function used to check if addr is marked.

In This routine must be called just prior to resuming all threads.

nothrow @nogc void* thread_stackTop();
Returns the stack top of the currently active stack within the calling thread.

In The calling thread must be attached to the runtime.

Returns:
The address of the stack top.
nothrow @nogc void* thread_stackBottom();
Returns the stack bottom of the currently active stack within the calling thread.

In The calling thread must be attached to the runtime.

Returns:
The address of the stack bottom.
package size_t ll_nThreads;
package ll_ThreadData* ll_pThreads;
package void[mutexClassInstanceSize] ll_lock;
package nothrow @nogc @property Mutex lowlevelLock();
package @nogc void initLowlevelThreads();
package @nogc void termLowlevelThreads();
package nothrow @nogc void ll_removeThread(ThreadID tid);
nothrow @nogc bool findLowLevelThread(ThreadID tid);
Check whether a thread was created by createLowLevelThread.
Parameters:
ThreadID tid the platform specific thread ID.
Returns:
true if the thread was created by createLowLevelThread and is still running.