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* dll_init.h (class dll_list): Reorder functions to avoid compiler "can't

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inline" warnings.
* security.h (class cygsid): Ditto.
* sigproc.cc (get_proc_lock): Ditto.
* sigproc.h (class sigframe): Ditto.
* sync.h (class muto): Ditto.
* fhandler.h (fhandler_base::get_guard): Actually MAKE virtual as previously
indicated.
* pipe.cc (make_pipe): Remove extraneous set_errno.
* syscalls.cc (_open): Ditto.
* select.cc (peek_pipe): Need to check that there is still something to read
from the pipe after acquiring the mutex since another process/thread could have
eaten the input before we got to acquiring the lock.  (Thanks to Nick Duffek
for this inspiration.)
This commit is contained in:
Christopher Faylor
2001-11-03 03:32:27 +00:00
parent 01432054cb
commit 243a041bd0
10 changed files with 87 additions and 58 deletions
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23
winsup/cygwin/select.cc
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@@ -389,7 +389,7 @@ peek_pipe (select_record *s, int ignra)
fhandler_base *fh = s->fh;
HANDLE h;
HANDLE guard_mutex = s->fh->get_guard ();
HANDLE guard_mutex = fh->get_guard ();
set_handle_or_return_if_not_open (h, s);
/* Don't perform complicated tests if we don't need to. */
@@ -438,12 +438,23 @@ peek_pipe (select_record *s, int ignra)
select_printf ("%s, PeekNamedPipe failed, %E", fh->get_name ());
n = -1;
}
else if (n && guard_mutex
&& WaitForSingleObject (guard_mutex, 0) != WAIT_OBJECT_0)
else if (n && guard_mutex)
{
select_printf ("%s, couldn't get mutex %p, %E", fh->get_name (),
guard_mutex);
n = 0;
if (WaitForSingleObject (guard_mutex, 0) != WAIT_OBJECT_0)
{
select_printf ("%s, couldn't get mutex %p, %E", fh->get_name (),
guard_mutex);
n = 0;
}
/* Now that we have the mutex, make sure that no one else has snuck
in and grabbed the data that we originally saw. */
if (!PeekNamedPipe (h, NULL, 0, NULL, (DWORD *) &n, NULL))
{
select_printf ("%s, PeekNamedPipe failed, %E", fh->get_name ());
n = -1;
}
if (n <= 0)
ReleaseMutex (guard_mutex); /* Oops. We lost the race. */
}
if (n < 0)