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, 235 insertions, 0 deletions

diff --git a/linuxthreads/man/pthread_cond_init.man b/linuxthreads/man/pthread_cond_init.man
new file mode 100644
index 0000000000..b803f08361
--- /dev/null
+++ b/linuxthreads/man/pthread_cond_init.man
@@ -0,0 +1,235 @@
+.TH PTHREAD_COND 3 LinuxThreads
+
+.XREF pthread_cond_signal
+.XREF pthread_cond_broadcast
+.XREF pthread_cond_wait
+.XREF pthread_cond_timedwait
+.XREF pthread_cond_destroy
+
+.SH NAME
+pthread_cond_init, pthread_cond_destroy, pthread_cond_signal, pthread_cond_broadcast, pthread_cond_wait, pthread_cond_timedwait \- operations on conditions
+
+.SH SYNOPSIS
+#include <pthread.h>
+
+pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
+
+int pthread_cond_init(pthread_cond_t *cond, pthread_condattr_t *cond_attr);
+
+int pthread_cond_signal(pthread_cond_t *cond);
+
+int pthread_cond_broadcast(pthread_cond_t *cond);
+
+int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex);
+
+int pthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex, const struct timespec *abstime);
+
+int pthread_cond_destroy(pthread_cond_t *cond);
+
+.SH DESCRIPTION
+
+A condition (short for ``condition variable'') is a synchronization
+device that allows threads to suspend execution and relinquish the
+processors until some predicate on shared data is satisfied. The basic
+operations on conditions are: signal the condition (when the
+predicate becomes true), and wait for the condition, suspending the
+thread execution until another thread signals the condition.
+
+A condition variable must always be associated with a mutex, to avoid
+the race condition where a thread prepares to wait on a condition
+variable and another thread signals the condition just before the
+first thread actually waits on it.
+
+!pthread_cond_init! initializes the condition variable |cond|, using the
+condition attributes specified in |cond_attr|, or default attributes
+if |cond_attr| is !NULL!. The LinuxThreads implementation supports no
+attributes for conditions, hence the |cond_attr| parameter is actually
+ignored.
+
+Variables of type !pthread_cond_t! can also be initialized
+statically, using the constant !PTHREAD_COND_INITIALIZER!.
+
+!pthread_cond_signal! restarts one of the threads that are waiting on
+the condition variable |cond|. If no threads are waiting on |cond|,
+nothing happens. If several threads are waiting on |cond|, exactly one
+is restarted, but it is not specified which.
+
+!pthread_cond_broadcast! restarts all the threads that are waiting on
+the condition variable |cond|. Nothing happens if no threads are
+waiting on |cond|.
+
+!pthread_cond_wait! atomically unlocks the |mutex| (as per
+!pthread_unlock_mutex!) and waits for the condition variable |cond| to
+be signaled. The thread execution is suspended and does not consume
+any CPU time until the condition variable is signaled. The |mutex|
+must be locked by the calling thread on entrance to
+!pthread_cond_wait!. Before returning to the calling thread,
+!pthread_cond_wait! re-acquires |mutex| (as per !pthread_lock_mutex!).
+
+Unlocking the mutex and suspending on the condition variable is done
+atomically. Thus, if all threads always acquire the mutex before
+signaling the condition, this guarantees that the condition cannot be
+signaled (and thus ignored) between the time a thread locks the mutex
+and the time it waits on the condition variable.
+
+!pthread_cond_timedwait! atomically unlocks |mutex| and waits on
+|cond|, as !pthread_cond_wait! does, but it also bounds the duration
+of the wait. If |cond| has not been signaled within the amount of time
+specified by |abstime|, the mutex |mutex| is re-acquired and
+!pthread_cond_timedwait! returns the error !ETIMEDOUT!. 
+The |abstime| parameter specifies an absolute time, with the same
+origin as !time!(2) and !gettimeofday!(2): an |abstime| of 0
+corresponds to 00:00:00 GMT, January 1, 1970.
+
+!pthread_cond_destroy! destroys a condition variable, freeing the
+resources it might hold. No threads must be waiting on the condition
+variable on entrance to !pthread_cond_destroy!. In the LinuxThreads
+implementation, no resources are associated with condition variables,
+thus !pthread_cond_destroy! actually does nothing except checking that
+the condition has no waiting threads.
+
+.SH CANCELLATION
+
+!pthread_cond_wait! and !pthread_cond_timedwait! are cancellation
+points. If a thread is cancelled while suspended in one of these
+functions, the thread immediately resumes execution, then locks again
+the |mutex| argument to !pthread_cond_wait! and
+!pthread_cond_timedwait!, and finally executes the cancellation.
+Consequently, cleanup handlers are assured that |mutex| is locked when
+they are called.
+
+.SH "ASYNC-SIGNAL SAFETY"
+
+The condition functions are not async-signal safe, and should not be
+called from a signal handler. In particular, calling
+!pthread_cond_signal! or !pthread_cond_broadcast! from a signal
+handler may deadlock the calling thread.
+
+.SH "RETURN VALUE"
+
+All condition variable functions return 0 on success and a non-zero
+error code on error.
+
+.SH ERRORS
+
+!pthread_cond_init!, !pthread_cond_signal!, !pthread_cond_broadcast!,
+and !pthread_cond_wait! never return an error code.
+
+The !pthread_cond_timedwait! function returns the following error codes
+on error:
+.RS
+.TP
+!ETIMEDOUT!
+the condition variable was not signaled until the timeout specified by
+|abstime|
+
+.TP
+!EINTR!
+!pthread_cond_timedwait! was interrupted by a signal
+.RE
+
+The !pthread_cond_destroy! function returns the following error code
+on error:
+.RS
+.TP
+!EBUSY!
+some threads are currently waiting on |cond|.
+.RE
+
+.SH AUTHOR
+Xavier Leroy <Xavier.Leroy@inria.fr>
+
+.SH "SEE ALSO"
+!pthread_condattr_init!(3),
+!pthread_mutex_lock!(3),
+!pthread_mutex_unlock!(3),
+!gettimeofday!(2),
+!nanosleep!(2).
+
+.SH EXAMPLE
+
+Consider two shared variables |x| and |y|, protected by the mutex |mut|,
+and a condition variable |cond| that is to be signaled whenever |x|
+becomes greater than |y|.
+
+.RS
+.ft 3
+.nf
+.sp
+int x,y;
+pthread_mutex_t mut = PTHREAD_MUTEX_INITIALIZER;
+pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
+.ft
+.LP
+.RE
+.fi
+
+Waiting until |x| is greater than |y| is performed as follows:
+
+.RS
+.ft 3
+.nf
+.sp
+pthread_mutex_lock(&mut);
+while (x <= y) {
+        pthread_cond_wait(&cond, &mut);
+}
+/* operate on x and y */
+pthread_mutex_unlock(&mut);
+.ft
+.LP
+.RE
+.fi
+
+Modifications on |x| and |y| that may cause |x| to become greater than
+|y| should signal the condition if needed:
+
+.RS
+.ft 3
+.nf
+.sp
+pthread_mutex_lock(&mut);
+/* modify x and y */
+if (x > y) pthread_mutex_broadcast(&cond);
+pthread_mutex_unlock(&mut);
+.ft
+.LP
+.RE
+.fi
+
+If it can be proved that at most one waiting thread needs to be waken
+up (for instance, if there are only two threads communicating through
+|x| and |y|), !pthread_cond_signal! can be used as a slightly more
+efficient alternative to !pthread_cond_broadcast!. In doubt, use
+!pthread_cond_broadcast!.
+
+To wait for |x| to becomes greater than |y| with a timeout of 5
+seconds, do:
+
+.RS
+.ft 3
+.nf
+.sp
+struct timeval now;
+struct timespec timeout;
+int retcode;
+
+pthread_mutex_lock(&mut);
+gettimeofday(&now);
+timeout.tv_sec = now.tv_sec + 5;
+timeout.tv_nsec = now.tv_usec * 1000;
+retcode = 0;
+while (x <= y && retcode != ETIMEDOUT) {
+        retcode = pthread_cond_timedwait(&cond, &mut, &timeout);
+}
+if (retcode == ETIMEDOUT) {
+        /* timeout occurred */
+} else {
+        /* operate on x and y */
+}
+pthread_mutex_unlock(&mut);
+.ft
+.LP
+.RE
+.fi
+