From a24ad2c346471f3066e051459112341c02a039fc Mon Sep 17 00:00:00 2001 From: Corinna Vinschen Date: Sun, 2 Jun 2013 10:22:14 +0000 Subject: * autoload.cc (CancelSynchronousIo): Define. * fcntl.cc (fcntl64): Drop handling of locking commands. * fhandler.h (class fhandler_disk_file): Add mandatory_locking. (fhandler_disk_file::fcntl): Declare. (fhandler_disk_file::mand_lock): Declare. * fhandler_disk_file.cc (fhandler_disk_file::fhandler_disk_file): Initialize mandatory_locking. (fhandler_disk_file::fcntl): New method. Handle F_LCK_MANDATORY and locking commands. (fhandler_disk_file::dup): Duplicate mandatory_locking. Fix a bug when duplicating prw_handle failed. (fhandler_disk_file::fixup_after_fork): Reset mandatory_locking. * flock.cc (fhandler_disk_file::lock): Add comment. (struct lock_parms): New struct to pass parameters to blocking_lock_thr thread function. (blocking_lock_thr): New thread function. (fhandler_disk_file::mand_lock): New methof implementing mandatory locking with Windows semantics. * ntdll.h (NtLockFile): Declare. (NtUnlockFile): Declare. * include/fcntl.h: Fix a comment. (F_LCK_MANDATORY): Define. Add lengthy comment to explain. --- winsup/cygwin/include/fcntl.h | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) (limited to 'winsup/cygwin/include/fcntl.h') diff --git a/winsup/cygwin/include/fcntl.h b/winsup/cygwin/include/fcntl.h index 9c3ddf926..fe8a1fc42 100644 --- a/winsup/cygwin/include/fcntl.h +++ b/winsup/cygwin/include/fcntl.h @@ -1,6 +1,6 @@ /* fcntl.h - Copyright 1996, 1998, 2000, 2001, 2005, 2006, 2009, 2010 Red Hat, Inc. + Copyright 1996, 1998, 2000, 2001, 2005, 2006, 2009, 2010, 2013 Red Hat, Inc. This file is part of Cygwin. @@ -14,12 +14,29 @@ details. */ #include #define O_NDELAY _FNDELAY -/* sys/fcntl defines values up to 0x40000 (O_NOINHERIT). */ +/* sys/_default_fcntl.h defines values up to 0x40000 (O_NOINHERIT). */ #define _FDIRECT 0x80000 #define _FNOFOLLOW 0x100000 #define _FDIRECTORY 0x200000 #define _FEXECSRCH 0x400000 +/* F_LCK_MANDATORY: Request mandatory locks for this file descriptor. + + Cygwin extension to fcntl file locking mechanism. By default, fcntl file + locks are advisory locks. This works nicely as long as only Cygwin + processes interact. If you have the requirement to interact with native + Windows applications which use Windows mandatory file locking, your have + to use mandatory locking as well. The command + + fcntl (fd, F_LCK_MANDATORY, 1) + + switches subsequent F_GETLK, F_SETLK, F_SETLKW calls to mandatory locking + for this file descriptor and subsequently duplicated ones WITHIN THE SAME + PROCESS. Note that mandatory locks are NOT inherited by child processes, + nor do they survive an execve call. This fully corresponds to Windows + mandatory locking semantics. */ +#define F_LCK_MANDATORY 0x99 + /* POSIX-1.2008 requires this flag and allows to set it to 0 if its functionality is not required. */ #define O_TTY_INIT 0 -- cgit v1.2.3