[src/trunk]: src/lib/libpthread Rationalize by moving

[jruoho <jruoho%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a10f7d365024
branches:  trunk
changeset: 756234:a10f7d365024
user:      jruoho <jruoho%NetBSD.org@localhost>
date:      Fri Jul 09 08:22:04 2010 +0000

description:
Rationalize by moving

        pthread_key_delete(3) to pthread_key_create(3); and
        pthread_setspecific(3) to pthread_getspecific(3)

diffstat:

 lib/libpthread/Makefile              |    8 +-
 lib/libpthread/pthread_getspecific.3 |   55 ++++++++-----
 lib/libpthread/pthread_key_create.3  |  101 ++++++++++++++++++-------
 lib/libpthread/pthread_key_delete.3  |  133 -----------------------------------
 lib/libpthread/pthread_setspecific.3 |  125 --------------------------------
 5 files changed, 111 insertions(+), 311 deletions(-)

diffs (truncated from 555 to 300 lines):

diff -r 70b00de894ca -r a10f7d365024 lib/libpthread/Makefile
--- a/lib/libpthread/Makefile   Fri Jul 09 08:10:50 2010 +0000
+++ b/lib/libpthread/Makefile   Fri Jul 09 08:22:04 2010 +0000
@@ -1,4 +1,4 @@
-#      $NetBSD: Makefile,v 1.68 2010/07/09 07:31:01 jruoho Exp $
+#      $NetBSD: Makefile,v 1.69 2010/07/09 08:22:04 jruoho Exp $
 #
 
 WARNS= 4
@@ -105,11 +105,11 @@
        pthread_exit.3 \
        pthread_getname_np.3 \
        pthread_getspecific.3 pthread_join.3 \
-       pthread_key_create.3 pthread_key_delete.3 pthread_kill.3 \
+       pthread_key_create.3 pthread_kill.3 \
        pthread_mutex.3 pthread_mutexattr.3 \
        pthread_once.3 pthread_rwlock.3 pthread_rwlockattr.3 \
        pthread_schedparam.3 pthread_self.3 \
-       pthread_setspecific.3 pthread_sigmask.3 pthread_spin.3 \
+       pthread_sigmask.3 pthread_spin.3 \
        pthread_suspend_np.3 pthread_testcancel.3
 
 MLINKS+=       affinity.3 pthread_setaffinity_np.3
@@ -155,6 +155,8 @@
 MLINKS+=       pthread_condattr.3 pthread_condattr_destroy.3
 
 MLINKS+=       pthread_getname_np.3 pthread_setname_np.3
+MLINKS+=       pthread_getspecific.3 pthread_setspecific.3
+MLINKS+=       pthread_key_create.3 pthread_key_delete.3
 
 MLINKS+=       pthread_mutex.3 pthread_mutex_init.3
 MLINKS+=       pthread_mutex.3 pthread_mutex_destroy.3
diff -r 70b00de894ca -r a10f7d365024 lib/libpthread/pthread_getspecific.3
--- a/lib/libpthread/pthread_getspecific.3      Fri Jul 09 08:10:50 2010 +0000
+++ b/lib/libpthread/pthread_getspecific.3      Fri Jul 09 08:22:04 2010 +0000
@@ -1,6 +1,6 @@
-.\" $NetBSD: pthread_getspecific.3,v 1.3 2008/05/02 18:11:04 martin Exp $
+.\" $NetBSD: pthread_getspecific.3,v 1.4 2010/07/09 08:22:04 jruoho Exp $
 .\"
-.\" Copyright (c) 2002 The NetBSD Foundation, Inc.
+.\" Copyright (c) 2002, 2010 The NetBSD Foundation, Inc.
 .\" All rights reserved.
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
@@ -55,39 +55,50 @@
 .\"
 .\" $FreeBSD: src/lib/libpthread/man/pthread_getspecific.3,v 1.11 2002/09/16 19:29:28 mini Exp $
 .\"
-.Dd January 30, 2003
+.Dd July 9, 2010
 .Dt PTHREAD_GETSPECIFIC 3
 .Os
 .Sh NAME
 .Nm pthread_getspecific
-.Nd get a thread-specific data value
+.Nd thread-specific data value
 .Sh LIBRARY
 .Lb libpthread
 .Sh SYNOPSIS
 .In pthread.h
 .Ft void *
 .Fn pthread_getspecific "pthread_key_t key"
+.Ft int
+.Fn pthread_setspecific "pthread_key_t key" "const void *value"
 .Sh DESCRIPTION
 The
 .Fn pthread_getspecific
 function returns the value currently bound to the specified
 .Fa key
 on behalf of the calling thread.
+Conversely, the
+.Fn pthread_setspecific
+function associates a thread-specific value with a
+.Fa key
+obtained via a previous call to
+.Xr pthread_key_create 3 .
+Different threads have different values bound to each key.
+These values are typically pointers to blocks of dynamically
+allocated memory that have been reserved for use by the calling thread.
 .Pp
-The effect of calling
-.Fn pthread_getspecific
-with a
+Undefined behavior may follow if either function is called with a
 .Fa key
 value not obtained from
-.Fn pthread_key_create
-or after
+.Xr pthread_key_create 3 ,
+or if the call is made after
 .Fa key
 has been deleted with
-.Fn pthread_key_delete
-is undefined.
-.Pp
-.Fn pthread_getspecific
-may be called from a thread-specific data destructor function.
+.Xr pthread_key_delete 3 .
+It is possible to call either function from
+a thread-specific data destructor function.
+Note however that this is not well defined for the
+.Fn pthread_setspecific
+function;
+lost storage or infinite loops may occur.
 .Sh RETURN VALUES
 The
 .Fn pthread_getspecific
@@ -96,13 +107,15 @@
 If no thread-specific data value is associated with
 .Fa key ,
 then the value NULL is returned.
+If successful,  the
+.Fn pthread_setspecific
+function will return zero.
+Otherwise an error number will be returned to
+indicate the error.
 .Sh ERRORS
-None.
+No errors are defined for either function.
 .Sh SEE ALSO
-.Xr pthread_key_create 3 ,
-.Xr pthread_key_delete 3 ,
-.Xr pthread_setspecific 3
+.Xr pthread_key_create 3
 .Sh STANDARDS
-.Fn pthread_getspecific
-conforms to
-.St -p1003.1-96 .
+These functions conform to
+.St -p1003.1-2001 .
diff -r 70b00de894ca -r a10f7d365024 lib/libpthread/pthread_key_create.3
--- a/lib/libpthread/pthread_key_create.3       Fri Jul 09 08:10:50 2010 +0000
+++ b/lib/libpthread/pthread_key_create.3       Fri Jul 09 08:22:04 2010 +0000
@@ -1,6 +1,6 @@
-.\" $NetBSD: pthread_key_create.3,v 1.4 2008/05/02 18:11:04 martin Exp $
+.\" $NetBSD: pthread_key_create.3,v 1.5 2010/07/09 08:22:04 jruoho Exp $
 .\"
-.\" Copyright (c) 2002 The NetBSD Foundation, Inc.
+.\" Copyright (c) 2002, 2010 The NetBSD Foundation, Inc.
 .\" All rights reserved.
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
@@ -55,46 +55,46 @@
 .\"
 .\" $FreeBSD: src/lib/libpthread/man/pthread_key_create.3,v 1.12 2002/09/16 19:29:28 mini Exp $
 .\"
-.Dd January 30, 2003
+.Dd July 9, 2010
 .Dt PTHREAD_KEY_CREATE 3
 .Os
 .Sh NAME
 .Nm pthread_key_create
-.Nd thread-specific data key creation
+.Nd thread-specific data
 .Sh LIBRARY
 .Lb libpthread
 .Sh SYNOPSIS
 .In pthread.h
 .Ft int
 .Fn pthread_key_create "pthread_key_t *key" "void (*destructor)(void *)"
+.Ft int
+.Fn pthread_key_delete "pthread_key_t key"
 .Sh DESCRIPTION
 The
 .Fn pthread_key_create
 function creates a thread-specific data key visible to all threads in the
 process.
-Key values provided by
-.Fn pthread_key_create
-are opaque objects used to locate thread-specific data.
-Although the same
-key value may be used by different threads, the values bound to the key
-by
+Key values are opaque objects used to locate thread-specific data.
+The same key value may be used by different threads,
+but the values bound to the key by
 .Fn pthread_setspecific
-are maintained on a per-thread basis and persist for the life of the calling
-thread.
+are maintained on a per-thread basis and
+persist for the life of the calling thread.
 .Pp
-Upon key creation, the value NULL is associated with the new key in all
-active threads.
-Upon thread creation, the value NULL is associated with all
+Upon key creation, the value
+.Dv NULL
+is associated with the new key in all active threads.
+Upon thread creation, the value
+.Dv NULL
+is associated with all
 defined keys in the new thread.
 .Pp
 An optional destructor function may be associated with each key value.
-At
-thread exit, if a key value has a non-NULL destructor pointer, and the
+At thread exit, if a key value has a non-NULL destructor pointer, and the
 thread has a non-NULL value associated with the key, the function pointed
 to is called with the current associated value as its sole argument.
-The
-order of destructor calls is unspecified if more than one destructor exists
-for a thread when it exits.
+The order of destructor calls is unspecified if more
+than one destructor exists for a thread when it exits.
 .Pp
 If, after all the destructors have been called for all non-NULL values
 with associated destructors, there are still some non-NULL values with
@@ -104,17 +104,47 @@
 iterations of destructor calls for
 outstanding non-NULL values, there are still some non-NULL values with
 associated destructors, the implementation stops calling destructors.
+.Pp
+The
+.Fn pthread_key_delete
+function deletes a thread-specific data key previously returned by
+.Fn pthread_key_create .
+The thread-specific data values associated with
+.Fa key
+need not be NULL at the time of the call.
+It is the responsibility of the application to free any
+application storage or perform any cleanup actions for data structures
+related to the deleted key or associated thread-specific data in any threads;
+this cleanup can be done either before or after
+.Fn pthread_key_delete
+is called.
+Any attempt to use
+.Fa key
+following the call to
+.Fn pthread_key_delete
+results in undefined behavior.
+.Pp
+The
+.Fn pthread_key_delete
+function itself is callable from within destructor functions,
+but destructor functions are not invoked by the function.
+Any destructor function that may have been associated with
+.Fa key
+will no longer be called upon thread exit.
 .Sh RETURN VALUES
 If successful, the
 .Fn pthread_key_create
 function will store the newly created key value at the location specified by
 .Fa key
 and returns zero.
-Otherwise an error number will be returned to indicate
-the error.
+Also
+.Fn pthread_key_delete
+will return zero upon success.
+Upon failure both functions return an error number to indicate the cause.
 .Sh ERRORS
+The
 .Fn pthread_key_create
-shall fail if:
+may fail if:
 .Bl -tag -width Er
 .It Bq Er EAGAIN
 The system lacked the necessary resources to create another thread-specific
@@ -124,11 +154,24 @@
 .It Bq Er ENOMEM
 Insufficient memory exists to create the key.
 .El
+.Pp
+The
+.Fn pthread_key_delete
+function may fail if:
+.Bl -tag -width Er
+.It Bq Er EINVAL
+The
+.Fa key
+value is invalid.
+.El
 .Sh SEE ALSO
-.Xr pthread_getspecific 3 ,
-.Xr pthread_key_delete 3 ,
-.Xr pthread_setspecific 3
+.Xr pthread_getspecific 3
 .Sh STANDARDS
-.Fn pthread_key_create
-conforms to
-.St -p1003.1-96 .
+These functions conform to
+.St -p1003.1-2001 .
+.Sh BUGS
+The current specifications are flawed and
+do not permit a clean implementation without potential problems.
+The current implementation in
+.Nx
+addresses these problems by not supporting key reuse.
diff -r 70b00de894ca -r a10f7d365024 lib/libpthread/pthread_key_delete.3
--- a/lib/libpthread/pthread_key_delete.3       Fri Jul 09 08:10:50 2010 +0000
+++ /dev/null   Thu Jan 01 00:00:00 1970 +0000
@@ -1,133 +0,0 @@
-.\" $NetBSD: pthread_key_delete.3,v 1.6 2008/05/02 18:11:04 martin Exp $
-.\"
-.\" Copyright (c) 2002 The NetBSD Foundation, Inc.
-.\" All rights reserved.
-.\" Redistribution and use in source and binary forms, with or without
-.\" modification, are permitted provided that the following conditions
-.\" are met: