haiku/headers/os/kernel/fcntl.h
ejakowatz 52a3801208 It is accomplished ...
git-svn-id: file:///srv/svn/repos/haiku/trunk/current@10 a95241bf-73f2-0310-859d-f6bbb57e9c96
2002-07-09 12:24:59 +00:00

342 lines
10 KiB
C

/*-
* Copyright (c) 1983, 1990, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)fcntl.h 8.3 (Berkeley) 1/21/94
*/
/**
* @file fcntl.h
* @brief File Control functions and definitions
*/
#ifndef _FCNTL_H_
#define _FCNTL_H_
/**
* @defgroup Fcntl fcntl.h
* @brief File Control functions and definitions
* @note Definitions in this file also apply to open() and
* internally in the kernel
* @note Relevant kernel functions should be here as well
* @ingroup OpenBeOS_POSIX
* @{
*/
#ifndef _KERNEL_
//#include <sys/types.h>
#endif
/**
* @defgroup File_Status_Flags File Status Flags
* The flags described in this section are used by fcntl(), open() and also
* withing the kernel.
* @note O_ are used by fcntl() and open()
* @note F flags are used by the kernel
* @ingroup fcntl
* @{
*/
/** open for reading only */
#define O_RDONLY 0x0000
/** open for writing only */
#define O_WRONLY 0x0001
/** open for reading and writing */
#define O_RDWR 0x0002
/** mask for above modes */
#define O_ACCMODE 0x0003
#ifndef _POSIX_SOURCE
/** kernel flag to allow testing of read/write directly
* @note not #ifdef _KERNEL_ to allow TIOCFLUSH to work */
#define FREAD 0x0001
/** kernel flag to allow testing of read/write directly
* @note not #ifdef _KERNEL_ to allow TIOCFLUSH to work */
#define FWRITE 0x0002
#endif
/** no delay */
#define O_NONBLOCK 0x0004
/** set append mode */
#define O_APPEND 0x0008
/** open with shared file lock */
#define O_SHLOCK 0x0010
/** open with exclusive file lock */
#define O_EXLOCK 0x0020
/** signal pgrp when data ready */
#define O_ASYNC 0x0040
/** backwards compatibility */
#define O_FSYNC O_SYNC
/** if path is a symlink, don't follow */
#define O_NOFOLLOW 0x0100
/** synchronous writes */
#define O_SYNC 0x0080
/** create if nonexistant */
#define O_CREAT 0x0200
/** truncate to zero length */
#define O_TRUNC 0x0400
/** error if already exists */
#define O_EXCL 0x0800
#ifdef _KERNEL_
/* mark during gc() */
#define FMARK 0x1000
/* defer for next gc pass */
#define FDEFER 0x2000
/* descriptor holds advisory lock */
#define FHASLOCK 0x4000
#endif
/*
* POSIX 1003.1 specifies a higher granularity for syncronous operations
* than are currently supported. We may want to look at what needs to be done
* to support these. At present just map them.
*/
/** @def O_DSYNC synchronous data writes */
#define O_DSYNC O_SYNC
/** @def O_RSYNC synchronous reads */
#define O_RSYNC O_SYNC
/* defined by POSIX 1003.1; BSD default, this bit is not required */
/** @def O_NOCTTY don't assign controlling terminal */
#define O_NOCTTY 0x8000
#ifdef _KERNEL_
/*
* convert from open() flags to/from fflags; convert O_RD/WR to FREAD/FWRITE.
* For out-of-range values for the flags, be slightly careful (but lossy).
*/
/** @def FFLAGS(oflags) Convert from O_ flags to F flags for kernel */
#define FFLAGS(oflags) (((oflags) & ~O_ACCMODE) | (((oflags) + 1) & O_ACCMODE))
/** @def OFLAGS(fflags) Convert from F flags to O_ flags for open() */
#define OFLAGS(fflags) (((fflags) & ~O_ACCMODE) | (((fflags) - 1) & O_ACCMODE))
/** @def FMASK bits to save after open */
#define FMASK (FREAD|FWRITE|FAPPEND|FASYNC|FFSYNC|FNONBLOCK)
/** @def FCNTLFLAGS bits settable by fcntl(F_SETFL, ...) */
#define FCNTLFLAGS (FAPPEND|FASYNC|FFSYNC|FNONBLOCK)
#endif
/*
* The O_* flags used to have only F* names, which were used in the kernel
* and by fcntl. We retain the F* names for the kernel f_flags field
* and for backward compatibility for fcntl.
*/
#ifndef _POSIX_SOURCE
/** kernel/compat */
#define FAPPEND O_APPEND
/** kernel/compat */
#define FASYNC O_ASYNC
/** kernel */
#define FFSYNC O_SYNC
/** kernel */
#define FNONBLOCK O_NONBLOCK
/** compat */
#define FNDELAY O_NONBLOCK
/** compat */
#define O_NDELAY O_NONBLOCK
#endif
/** @} */
/**
* @defgroup FCNTL_Flags Flags used for fcntl()
* @ingroup FCNTL
* @{
*/
/**
* @def F_DUPFD Return a new file descriptor that has
* @li the lowest number available (>= fd used)
* @li same object references as original fd
* @li same offsets as original (file only)
* @li same file status
* @li close-on-exec flag is set so it will remain open across execv()
*
* @ref FD_CLOEXEC
*/
#define F_DUPFD 0 /* duplicate file descriptor */
/** @def F_GETFD Get the close-on-exec flag for the fd
* @note the argument is ignored
* @ref FD_CLOEXEC */
#define F_GETFD 1
/** @def F_SETFD Set the close-on-exec flag for the fd
* @ref FD_CLOEXEC */
#define F_SETFD 2
/** @def F_GETFL Get fd status flags */
#define F_GETFL 3
/** @def F_SETFL Set the fd status flags */
#define F_SETFL 4
/** @def F_GETOWN Get the process ID receiving SIGIO/SIGURG signals */
#define F_GETOWN 5
/** @def F_SETOWN Set the process ID receiving SIGIO/SIGURG signals */
#define F_SETOWN 6
/** @def F_GETLK Get the first lock that blocks the requested lock requested
* int the flock structure passed in.
* @li If the call succeeds then the structure is returned unaltered except
* the lock type is set to F_UNLCK
* @li If the call fails the details of the blocking lock will be inserted
* into the strcture, overwriting the details submitted.
*/
#define F_GETLK 7
/** @def F_SETLK Set/Clear a file segment lock based on the flock structure
* passed in.
* @note If a shared/exclusive lock cannot be set, EAGAIN will be returned
*/
#define F_SETLK 8
/** @def F_SETLKW Same as F_SETLK but will block if a shared/exclusive
* lock is requested and is not available.
*/
#define F_SETLKW 9
/* file descriptor flags (F_GETFD, F_SETFD) */
/** @def FD_CLOEXEC Flag set in status is fd is set to remain open
* across exec
* @ref F_DUPFD
* @ref F_GETFD
* @ref F_SETFD
*/
#define FD_CLOEXEC 1 /* close-on-exec flag */
/** @} */
/**
* @defgroup FCNTL_FileLocks Locking types for fcntl()
* @ingroup FCNTL
* @{
*/
/** shared or read lock */
#define F_RDLCK 1
/** unlock */
#define F_UNLCK 2
/** exclusive or write lock */
#define F_WRLCK 3
#ifdef _KERNEL_
/** Wait until lock is granted */
#define F_WAIT 0x010
/** Use flock(2) semantics for lock */
#define F_FLOCK 0x020
/** Use POSIX semantics for lock */
#define F_POSIX 0x040
#endif
/** @} */
/**
* Advisory file segment locking data type -
* information passed to system by user
* @note This structure can be used to lock all or part of a file
* @note Not yet implemented in OpenBeOS
*/
struct flock {
/** starting offset for lock */
off_t l_start;
/** length of lock required (0 means lock to end of file) */
off_t l_len;
/** process id of process owning lock */
pid_t l_pid;
/** type of lock
* @link FCNTL_FileLocks */
short l_type;
/** type of start poition given */
short l_whence;
};
/**
* @defgroup FCNTL_flock Locking types for flock()
* @ingroup FCNTL
* @{
*/
/** shared lock */
#define LOCK_SH 0x01
/** exclusive lock */
#define LOCK_EX 0x02
/** don't block when locking */
#define LOCK_NB 0x04
/** unlock */
#define LOCK_UN 0x08
/** @} */
#ifndef _KERNEL_MODE
//#include <sys/cdefs.h>
#include <ktypes.h>
/** @fn int open(const char *path, int oflags, ...);
* Used to open or create a file for reading/writing
* @note oflags passed should be OR'd together, e.g.
* @code
* int fd = open("file.txt", O_RDWR | O_APPEND | O_CREAT);
* @endcode
* @note if the flag O_CREAT is supplied and the file given by path doesn't
* exist it will be created.
*
* @ref File_Status_Flags
*/
int open (const char *, int, ...);
/** @fn int creat(const char *path, mode_t mode)
* Creates a file.
* @note Obsoleted by open()
* @code
* Same as doing open(path, O_CREAT | O_TRUNC | O_WRONLY, mode);
* @endcode
* @ref open()
*/
int creat (const char *, mode_t);
/** @fn int fcntl(int fd, int cmd, ...)
* Provides control over the properties of a descriptor that is
* already open. The 3rd paramater is technically a void *, but may
* be interpretted as an int by some commands or cast by others.
* @ref FCNTL_Flags should be used as the cmd parameter
*/
int fcntl (int, int, ...);
/** @fn int flock(int fd, int operation)
* Applies or removes an advisory lock from descriptor fd.
* @ref FCNTL_flock codes should be used as the operation parameter
*/
int flock (int, int);
#endif
/** @} */
#endif /* !_SYS_FCNTL_H_ */