libc/winsup/cygwin/sync.h

50 lines
1.6 KiB
C++

/* sync.h: Header file for cygwin synchronization primitives.
Copyright 1999, 2000, 2001 Red Hat, Inc.
Written by Christopher Faylor <cgf@cygnus.com>
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
/* FIXME: Note that currently this class cannot be allocated via `new' since
there are issues with malloc and fork. */
class muto
{
LONG sync; /* Used to serialize access to this class. */
LONG visits; /* Count of number of times a thread has called acquire. */
LONG waiters; /* Number of threads waiting for lock. */
HANDLE bruteforce; /* event handle used to control waiting for lock. */
DWORD tid; /* Thread Id of lock owner. */
public:
class muto *next;
const char *name;
/* The real constructor. */
muto *init(const char *name) __attribute__ ((regparm (3)));
#if 0 /* FIXME: See comment in sync.cc */
~muto ()
#endif
int acquire (DWORD ms = INFINITE) __attribute__ ((regparm (1))); /* Acquire the lock. */
int release (); /* Release the lock. */
/* Return true if caller thread owns the lock. */
int ismine () {return tid == GetCurrentThreadId ();}
DWORD owner () {return tid;}
int unstable () {return !tid && (sync || waiters >= 0);}
void reset ();
};
extern muto muto_start;
/* Use a statically allocated buffer as the storage for a muto */
#define new_muto(__name) \
({ \
static muto __name##_storage __attribute__((nocommon)) __attribute__((section(".data_cygwin_nocopy"))); \
__name = __name##_storage.init (#__name); \
})