Fix the handle locking in stdio

Fix the handle locking in stdio to use flockfile/funlockfile
internally when and where required.  Macros in <stdio.h> are updated
to automatically call the underlying functions when the process is
threaded to obtain the necessary locking.  A private mutex is added
to protect __sglue, the internal list of FILE handles, and another
to protect the one-time initialization.  Some routines in libc that
use getc() change to use getc_unlocked() as they're either protected
by their own lock or aren't thread-safe routines anyway.

Based on OpenBSD change by guenther@openbsd.org
http://www.mail-archive.com/source-changes@cvs.openbsd.org/msg01015.html

Bug: 3446659
Change-Id: Ie82116e358c541718d6709ec45ca6796be5a007b
This commit is contained in:
Kenny Root
2011-02-12 07:13:44 -08:00
parent 72f9a5c374
commit f582340a6a
36 changed files with 239 additions and 92 deletions

View File

@@ -45,8 +45,9 @@ _fwalk(int (*function)(FILE *))
ret = 0;
for (g = &__sglue; g != NULL; g = g->next)
for (fp = g->iobs, n = g->niobs; --n >= 0; fp++)
if (fp->_flags != 0)
for (fp = g->iobs, n = g->niobs; --n >= 0; fp++) {
if ((fp->_flags != 0) && ((fp->_flags & __SIGN) == 0))
ret |= (*function)(fp);
}
return (ret);
}