Commit Graph

8 Commits

Author SHA1 Message Date
Daniel Eischen
29ac6bd228 libc MT-safety, part 2.
Add a lock to FILE.  flockfile and friends are now implemented
(for the most part) in libc.  flockfile_debug is implemented in
libc_r; I suppose it's about time to kill it but will do it in
a future commit.

Fix a potential deadlock in _fwalk in a threaded environment.
A file flag (__SIGN) was added to stdio.h that, when set, tells
_fwalk to ignore it in its walk.  This seemed to be needed in
refill.c because each file needs to be locked when flushing.

Add a stub for pthread_self in libc.  This is needed by flockfile
which is allowed by POSIX to be recursive.

Make fgetpos() error return value (-1) match man page.

Remove recursive calls to locked functions (stdio); I think I've
got them all, but I may have missed a couple.

A few K&R -> ANSI conversions along with removal of a few instances
of "register".

$Id$ -> $FreeBSD$ in libc/stdio/rget.c

Not objected to:	-arch, a few months ago
2001-02-11 22:06:43 +00:00
Daniel Eischen
d201fe46e3 Remove _THREAD_SAFE and make libc thread-safe by default by
adding (weak definitions to) stubs for some of the pthread
functions.  If the threads library is linked in, the real
pthread functions will pulled in.

Use the following convention for system calls wrapped by the
threads library:
	__sys_foo - actual system call
	_foo - weak definition to __sys_foo
	foo - weak definition to __sys_foo

Change all libc uses of system calls wrapped by the threads
library from foo to _foo.  In order to define the prototypes
for _foo(), we introduce namespace.h and un-namespace.h
(suggested by bde).  All files that need to reference these
system calls, should include namespace.h before any standard
includes, then include un-namespace.h after the standard
includes and before any local includes.  <db.h> is an exception
and shouldn't be included in between namespace.h and
un-namespace.h  namespace.h will define foo to _foo, and
un-namespace.h will undefine foo.

Try to eliminate some of the recursive calls to MT-safe
functions in libc/stdio in preparation for adding a mutex
to FILE.  We have recursive mutexes, but would like to avoid
using them if possible.

Remove uneeded includes of <errno.h> from a few files.

Add $FreeBSD$ to a few files in order to pass commitprep.

Approved by:	-arch
2001-01-24 13:01:12 +00:00
Peter Wemm
7f3dea244c $Id$ -> $FreeBSD$ 1999-08-28 00:22:10 +00:00
John Birrell
f374bfcd3c Implement compile time debug support for spinlocks.
Simplify the atomic lock prototype, removing the lock value.

Delete the unlock prototypes that are not required.
1998-06-09 08:28:49 +00:00
John Birrell
e095485cdb Remove leading underscores from the FILE lock functions that POSIX
specifies.
1998-05-05 22:02:29 +00:00
John Birrell
f1daac6f22 In a threaded library, expect the lock field to be declared volatile,
so provide function prototypes that respect that, avoiding a gcc
warning that `volatile' is being thrown away.
1998-05-05 21:46:30 +00:00
John Birrell
01c70c0055 Add a private header file for libc/libc_r/libpthread to contain
definitions for things like locking etc.
1998-04-11 06:57:33 +00:00
John Birrell
0a31d34120 Add a private (to libc, libc_r and libpthread) header file containing
prototypes for the spinlock functions that will be used for thread locks.
libc will have stubs declared with weak symbols. libpthread and libc_r
will have functions that really do something.
1998-03-09 05:05:32 +00:00