LinuxThreads library.

1998-03-11 00:42  Wolfram Gloger  <wmglo@dent.med.uni-muenchen.de>
	* linuxthreads/manager.c: Enable resetting of the thread
	scheduling policy to SCHED_OTHER when the parent thread
	has a different one.
1998-02-01 13:51  Ulrich Drepper  <drepper@cygnus.com>
	* sysdeps/unix/sysv/linux/bits/posix_opt.h: Define
	_POSIX_ASYNCHRONOUS_IO.
	* sysdeps/pthread/pthread.h: Define bits for Unix98 variants of
	mutexes.
	* mutex.c: Implement new mutex types.
	* internals.h: Include <signal.h>.
	* libpthread.map: Add __erno_location and __h_errno_location.
	* errno.c: Return pointer to variable actually in use.  This might
	not be the one in the thread structure.
	* internals.h (struct _pthread_descr_struct): Add new fields p_errnop
	and p_h_errnop.
	* manager.c (__pthread_manager): Set p_errnop and p_h_errnop member
	of manager thread structure.
	(pthread_handle_create): Set p_errnop and p_h_errnop members for new
	thread.
	* pthread.c: Adapt initializer for thread structures.
	(__pthread_initial_thread): Set p_errnop and p_h_errnop member.
	(__pthread_reset_main_thread): Reset p_errnop and p_h_errnop of
	current thread to global variables.
1998-01-31 17:27  Ulrich Drepper  <drepper@cygnus.com>
	* rwlock.c: New file.
	* Makefile (libpthread-routines): Add rwlock.
	* sysdeps/pthread/pthread.h: Define data structures and declare
	functions.
	* libpthread.map: Add new functions.
1997-12-18 13:50  Philip Blundell  <pb@nexus.co.uk>
	* sysdeps/arm/pt-machine.h: New file; add ARM support.
	* sysdeps/arm/Implies: likewise.
	* README: Document it.
1997-12-13  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>
	* signals.c: Remove unneeded initializer for sigwaited, saving a
1997-04-11 01:18  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>
	* semaphore.c (sem_init): Set sem_spinlock only if available.
1997-12-04 01:48  Ulrich Drepper  <drepper@cygnus.com>
	* mutex.c: Implement PTHREAD_MUTEX_CHECKERROR.
	* sysdeps/pthread/pthread.h: Define PTHREAD_MUTEX_CHECKERROR.
	* Makefile: Update from LinuxThreads 0.7.
	* internals.h. Likewise.
	* manager.c: Likewise.
	* mutex.c: Likewise.
	* pthread.c: Likewise.
	* signals.c: Likewise.
	* specific.c: Likewise.
	* Examples/ex3.c: Likewise.
1997-11-20 18:13  Ulrich Drepper  <drepper@cygnus.com>
	* pthread.c (__pthread_reset_main_thread): Close pipe only if still
	open.
1997-10-29 05:38  Ulrich Drepper  <drepper@cygnus.com>

	* wrapsyscall.c: Add socket functions which are also cancelation
	points.

1997-10-19 21:40  Wolfram Gloger  <wg@wolfram.dent.med.uni-muenchen.de>

	* specific.c (__libc_internal_tsd_set, __libc_internal_tsd_get):
	New functions for fast thread specific data within libc.

	* internals.h: Add new array p_libc_specific to struct
	_pthread_descr_struct.

	* sysdeps/pthread/bits/libc-lock.h: Declare new functions.

1997-10-13 05:39  Ulrich Drepper  <drepper@cygnus.com>

	* semaphore.h: Add __BEGIN_DECLS/__END_DECLS.
	Reported by Ralf Corsepius <corsepiu@faw.uni-ulm.de>.

1997-08-29 03:05  Ulrich Drepper  <drepper@cygnus.com>

	* internals.h (struct _pthread_descr_struct): Add definitions for
	two-level specific key handling.
	* manager.c (pthread_handle_create): Initialize specific memory array.
	* specific.c: Implement two-level key handling.
	* weaks.c: Don't provide dummy key handling.
	* sysdeps/pthread/bits/libc-lock.h: Typedef __libc_lock_t (no #define).
	Add definition of __libc_key_t.
	* sysdeps/unix/sysv/linux/bits/local_lim.h: Define PTHREAD_KEYS_MAX
	as 1024.
	Add definition of _POSIX_THREAD_DESTRUCTOR_ITERATIONS and
	PTHREAD_DESTRUCTOR_ITERATIONS.

	* manager.c (pthread_handle_create): Compare mmap result with
	MAP_FAILED.

	* ptfork.c: Rename to __pthread_atfork and make old name a weak alias.
	* sysdeps/pthread/bits/pthread.h: Add prototype for __pthread_atfork.

1997-08-22 19:04  Richard Henderson  <rth@cygnus.com>

	sysdeps/sparc -> sysdeps/sparc/sparc32
	sysdeps/sparc64 -> sysdeps/sparc/sparc64

	* internals.h: Change definition of THREAD_SELF to be an expression,
	not a statement that did a return.
	* sysdeps/alpha/pt-machine.h (THREAD_SELF): Update accordingly.
	* sysdeps/sparc/sparc32/pt-machine.h (THREAD_SELF, INIT_THREAD_SELF):
	Follow Solaris and use a "system reserved" register (%g6) to hold
	the thread descriptor.
	* sysdeps/sparc/sparc64/pt-machine.h: Likewise.

1997-08-03 00:09  Ulrich Drepper  <drepper@cygnus.com>

	* mutex.c: Correct pthread_once.  Patch by Xavier Leroy.
	* sysdeps/pthread/pthread.h: Add prototype for __pthread_once.
	* sysdeps/pthread/bits/pthread.h: Add macros for __libc_once.

	* semaphore.c: Include spinlock.h only when needed.

	* specific.c (__pthread_setsepcific, __pthread_getspecific): Reject
	keys for entries not in use.

	* weaks.c: Implement key handling functions for real.

1997-06-29  01:04  Richard Henderson  <richard@gnu.ai.mit.edu>

	Initial sparc64-linux support:
	* linuxthreads/sysdeps/sparc64/Implies: New file.
	* linuxthreads/sysdeps/sparc64/pt-machine.h: Likewise.

1997-06-29 00:48  Ulrich Drepper  <drepper@cygnus.com>

	* semaphore.c: Include spinlock.h at correct place.
	Patch by HJ Lu.

1997-06-13 10:06  Richard Henderson  <rth@tamu.edu>

	The Great Bit File Move:
	* sysdeps/alpha/semaphorebits.h: -> .../bits/semaphore.h.
	* sysdeps/powerpc/semaphorebits.h: Likewise.
	* sysdeps/pthread/cmpxchg/semaphorebits.h: Likewise.
	* sysdeps/pthread/no-cmpxchg/semaphorebits.h: Likewise.
	* sysdeps/pthread/libc-lock.h: -> bits/
	* sysdeps/pthread/stdio-lock.h: Likewise.
	* sysdeps/unix/sysv/linux/local_lim.h: Likewise.
	* sysdeps/unix/sysv/linux/posix_opt.h: Likewise.
	* semaphore.h: Likewise.
	* sysdeps/pthread/pthread.h: Likewise.

	* lockfile.c: <foo.h> -> <bits/foo.h>.
	* semaphore.h: Likewise.

	* Makefile: (headers): foo.h -> bits/foo.h.
	* sysdeps/pthread/Makefile: Likewise.

1997-04-11 01:18  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* semaphore.c (sem_init): Set sem_spinlock only if available.

	* sysdeps/m68k/pt-machine.h (testandset, __compare_and_swap): Fix
	asm constraints.

1997-04-09 03:00  Ulrich Drepper  <drepper@cygnus.com>

	Update from LinuxThreads 0.6.

	* attr.c (pthread_attr_getdetachstate): Use __sched_get_priority_max
	and __sched_get_priority_min instead of names without `__'.

	* manager.c: Rewrite large parts to implement opaque pthread_t.

	* cancel.c: Adapt for opaque pthread_t type.
	* condvar.c: Likewise.
	* errno.c: Likewise.
	* join.c: Likewise.
	* mutex.c: Likewise.
	* pthread.c: Likewise.
	* signals.c: Likewise.
	* specific.c: Likewise.
	* restart.h: Likewise.
	* queue.h: Likewise.
	* Examples/ex3.c: Likewise.
	* Examples/ex4.c: Likewise.
	* sysdeps/pthread/pthread.h: Likewise.

	* pthread.c: Accumulate time for all threads in thread manager.

	* semaphore.c: Implement fallback implementation for architectures
	sometimes missing compare-exchange operations.

	* cancel.c (pthread_cancel): Validate handle argument.
	* join.c (pthread_join): Likewise.
	(pthread_detach): Likewise.
	* signals.c (pthread_kill): Likewise.

	* spinlock.h (acquire): Use __sched_yield not sched_yield.

	* queue.h (enqueue): Enqueue thread according to priority.

	* internals.c (struct pthread_start_args): New struct for passing
	args to cloning function.
	(struct _pthread): Rename to _pthread_descr_struct and adapt for
	opaque pthread_t.

	* Examples/Makefile (clean): Pass -f option to rm.

	* sysdeps/i386/pt-machine.h: Add check for compare-exchange instruction
	and define TEST_FOR_COMPARE_AND_SWAP.
	* sysdeps/i386/i486/pt-machine.h: Removed.

	* sysdeps/unix/sysv/linux/local_lim.h (PTHREAD_THREADS_MAX): Increase
	to 1024.

1997-04-04 16:38  Ulrich Drepper  <drepper@cygnus.com>

	* restart.h (suspend): Clear p_signal before suspending.
	(suspend_with_cancellation): Likewise.
	Patch by Xavier Leroy <Xavier.Leroy@inria.fr>.

	* weaks.c: Make __pthread_key_create return 1.
	* sysdeps/pthread/libc-lock.h: Define __libc_key_create,
	__libc_getspecific, __libc_setspecific, and __libc_key_t.
	* sysdeps/pthread/stdio-lock.h: Don't care for implementation not
	using libio.

1997-03-19 15:13  Miguel de Icaza  <miguel@nuclecu.unam.mx>

	* sysdeps/sparc/pt-machine (RELEASE): Fix.

1997-03-01 07:55  Geoff Keating  <geoffk@ozemail.com.au>

	* sysdeps/powerpc/Implies: Added.
	* sysdeps/powerpc/pt-machine.h: Added.
	* sysdeps/powerpc/semaphorebits.h: Added.

1997-01-22 01:22  Ulrich Drepper  <drepper@cygnus.com>

	* linuxtheads/pthread.c (__pthread_initial_thread): Correct
	initializer.
	(__pthread_manager_thread): Likewise.
	Reported by Andreas Jaeger.

1997-01-18 22:15  Richard Henderson  <rth@tamu.edu>

	Since sigset_t no longer fits in a register, we can't pass in the
	thread's initial mask so easily.  Take this opportunity to simplify
	the clone implementation by only accepting a single void* argument.

	* linuxthreads/manager.c (__pthread_manager): Put thread vitals
	in the thread struct instead of as arguments through clone.
	(pthread_start_thread): Look for them there.
	* linuxthreads/internals.h (struct _pthread): Add p_initial_fn,
	p_initial_fn_arg, p_initial_mask.  Fix __pthread_manager proto.
	* linuxthreads/pthread.c (pthread_initialize_manager): Revise
	clone invocation.

1 files changed, 194 insertions, 0 deletions

diff --git a/linuxthreads/man/pthread_cleanup_push.man b/linuxthreads/man/pthread_cleanup_push.man
new file mode 100644
index 0000000000..1591431c9c
--- /dev/null
+++ b/linuxthreads/man/pthread_cleanup_push.man
@@ -0,0 +1,194 @@
+.TH PTHREAD_CLEANUP 3 LinuxThreads
+
+.XREF pthread_cleanup_pop
+.XREF pthread_cleanup_push_defer_np
+.XREF pthread_cleanup_pop_restore_np
+
+.SH NAME
+pthread_cleanup_push, pthread_cleanup_pop, pthread_cleanup_push_defer_np, pthread_cleanup_pop_restore_np \- install and remove cleanup handlers
+
+.SH SYNOPSIS
+#include <pthread.h>
+
+void pthread_cleanup_push(void (*routine) (void *), void *arg);
+
+void pthread_cleanup_pop(int execute);
+
+void pthread_cleanup_push_defer_np(void (*routine) (void *), void *arg);
+
+void pthread_cleanup_pop_restore_np(int execute);
+
+.SH DESCRIPTION
+
+Cleanup handlers are functions that get called when a thread
+terminates, either by calling !pthread_exit!(3) or because of
+cancellation. Cleanup handlers are installed and removed following a
+stack-like discipline.
+
+The purpose of cleanup handlers is to free the resources that a thread
+may hold at the time it terminates. In particular, if a thread
+exits or is cancelled while it owns a locked mutex, the mutex will
+remain locked forever and prevent other threads from executing
+normally. The best way to avoid this is, just before locking the
+mutex, to install a cleanup handler whose effect is to unlock the
+mutex. Cleanup handlers can be used similarly to free blocks allocated
+with !malloc!(3) or close file descriptors on thread termination.
+
+!pthread_cleanup_push! installs the |routine| function with argument
+|arg| as a cleanup handler. From this point on to the matching
+!pthread_cleanup_pop!, the function |routine| will be called with
+arguments |arg| when the thread terminates, either through !pthread_exit!(3)
+or by cancellation. If several cleanup handlers are active at that
+point, they are called in LIFO order: the most recently installed
+handler is called first.
+
+!pthread_cleanup_pop! removes the most recently installed cleanup
+handler. If the |execute| argument is not 0, it also executes the
+handler, by calling the |routine| function with arguments |arg|. If
+the |execute| argument is 0, the handler is only removed but not
+executed.
+
+Matching pairs of !pthread_cleanup_push! and !pthread_cleanup_pop!
+must occur in the same function, at the same level of block nesting.
+Actually, !pthread_cleanup_push! and !pthread_cleanup_pop! are macros,
+and the expansion of !pthread_cleanup_push! introduces an open brace !{!
+with the matching closing brace !}! being introduced by the expansion
+of the matching !pthread_cleanup_pop!.
+
+!pthread_cleanup_push_defer_np! is a non-portable extension that
+combines !pthread_cleanup_push! and !pthread_setcanceltype!(3).
+It pushes a cleanup handler just as !pthread_cleanup_push! does, but
+also saves the current cancellation type and sets it to deferred
+cancellation. This ensures that the cleanup mechanism is effective
+even if the thread was initially in asynchronous cancellation mode.
+
+!pthread_cleanup_pop_restore_np! pops a cleanup handler introduced by
+!pthread_cleanup_push_defer_np!, and restores the cancellation type to
+its value at the time !pthread_cleanup_push_defer_np! was called.
+
+!pthread_cleanup_push_defer_np! and !pthread_cleanup_pop_restore_np!
+must occur in matching pairs, at the same level of block nesting.
+
+The following sequence
+
+.RS
+.ft 3
+.nf
+.sp
+pthread_cleanup_push_defer_np(routine, arg);
+...
+pthread_cleanup_pop_defer_np(execute);
+.ft
+.LP
+.RE
+.fi
+
+is functionally equivalent to (but more compact and more efficient than)
+
+.RS
+.ft 3
+.nf
+.sp
+{ int oldtype;
+  pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, &oldtype);
+  pthread_cleanup_push(routine, arg);
+  ...
+  pthread_cleanup_pop(execute);
+  pthread_setcanceltype(oldtype, NULL);
+}
+.ft
+.LP
+.RE
+.fi
+
+.SH "RETURN VALUE"
+
+None.
+
+.SH ERRORS
+
+None.
+
+.SH AUTHOR
+Xavier Leroy <Xavier.Leroy@inria.fr>
+
+.SH "SEE ALSO"
+!pthread_exit!(3),
+!pthread_cancel!(3),
+!pthread_setcanceltype!(3).
+
+.SH EXAMPLE
+
+Here is how to lock a mutex |mut| in such a way that it will be
+unlocked if the thread is canceled while |mut| is locked:
+
+.RS
+.ft 3
+.nf
+.sp
+pthread_cleanup_push(pthread_mutex_unlock, (void *) &mut);
+pthread_mutex_lock(&mut);
+/* do some work */
+pthread_mutex_unlock(&mut);
+pthread_cleanup_pop(0);
+.ft
+.LP
+.RE
+.fi
+
+Equivalently, the last two lines can be replaced by
+
+.RS
+.ft 3
+.nf
+.sp
+pthread_cleanup_pop(1);
+.ft
+.LP
+.RE
+.fi
+
+Notice that the code above is safe only in deferred cancellation mode
+(see !pthread_setcanceltype!(3)). In asynchronous cancellation mode,
+a cancellation can occur between !pthread_cleanup_push! and
+!pthread_mutex_lock!, or between !pthread_mutex_unlock! and
+!pthread_cleanup_pop!, resulting in both cases in the thread trying to
+unlock a mutex not locked by the current thread. This is the main
+reason why asynchronous cancellation is difficult to use.
+
+If the code above must also work in asynchronous cancellation mode,
+then it must switch to deferred mode for locking and unlocking the
+mutex:
+
+.RS
+.ft 3
+.nf
+.sp
+pthread_setcanceltype(PTHREAD_CANCEL_DEFERRED, &oldtype);
+pthread_cleanup_push(pthread_mutex_unlock, (void *) &mut);
+pthread_mutex_lock(&mut);
+/* do some work */
+pthread_cleanup_pop(1);
+pthread_setcanceltype(oldtype, NULL);
+.ft
+.LP
+.RE
+.fi
+
+The code above can be rewritten in a more compact and more
+efficient way, using the non-portable functions
+!pthread_cleanup_push_defer_np! and !pthread_cleanup_pop_restore_np!:
+
+.RS
+.ft 3
+.nf
+.sp
+pthread_cleanup_push_restore_np(pthread_mutex_unlock, (void *) &mut);
+pthread_mutex_lock(&mut);
+/* do some work */
+pthread_cleanup_pop_restore_np(1);
+.ft
+.LP
+.RE
+.fi
+