winsup/cygwin/sync.h

   1 /* sync.h: Header file for cygwin synchronization primitives.
   2
   3    Copyright 1999, 2000, 2001, 2002, 2003, 2004 Red Hat, Inc.
   4
   5    Written by Christopher Faylor <cgf@cygnus.com>
   6
   7 This file is part of Cygwin.
   8
   9 This software is a copyrighted work licensed under the terms of the
  10 Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
  11 details. */
  12
  13 #ifndef _SYNC_H
  14 #define _SYNC_H
  15 /* FIXME: Note that currently this class cannot be allocated via `new' since
  16    there are issues with malloc and fork. */
  17 class muto
  18 {
  19   static DWORD exiting_thread;
  20   LONG sync;    /* Used to serialize access to this class. */
  21   LONG waiters; /* Number of threads waiting for lock. */
  22   HANDLE bruteforce; /* event handle used to control waiting for lock. */
  23 public:
  24   LONG visits;  /* Count of number of times a thread has called acquire. */
  25   DWORD tid;    /* Thread Id of lock owner. */
  26   // class muto *next;
  27   const char *name;
  28
  29   /* The real constructor. */
  30   muto *init(const char *name) __attribute__ ((regparm (3)));
  31
  32 #if 0   /* FIXME: See comment in sync.cc */
  33   ~muto ()
  34 #endif
  35   int acquire (DWORD ms = INFINITE) __attribute__ ((regparm (2))); /* Acquire the lock. */
  36   int release () __attribute__ ((regparm (1)));              /* Release the lock. */
  37
  38   /* Return true if caller thread owns the lock. */
  39   int ismine () {return tid == GetCurrentThreadId ();}
  40   DWORD owner () {return tid;}
  41   int unstable () {return !tid && (sync || waiters >= 0);}
  42   void reset () __attribute__ ((regparm (1)));
  43   bool acquired ();
  44   static void set_exiting_thread () {exiting_thread = GetCurrentThreadId ();}
  45 };
  46
  47 extern muto muto_start;
  48
  49 /* Use a statically allocated buffer as the storage for a muto */
  50 #define new_muto(__name) \
  51 ({ \
  52   static muto __name##_storage __attribute__((nocommon)) __attribute__((section(".data_cygwin_nocopy1"))); \
  53   __name = __name##_storage.init (#__name); \
  54 })
  55
  56 /* Use a statically allocated buffer as the storage for a muto */
  57 #define new_muto1(__name, __storage) \
  58 ({ \
  59   static muto __storage __attribute__((nocommon)) __attribute__((section(".data_cygwin_nocopy1"))); \
  60   __name = __storage.init (#__name); \
  61 })
  62 #endif /*_SYNC_H*/