/* * Copyright (c) 1990, 1993 * The Regents of the University of California. All rights reserved. * * 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. * * @(#)filedesc.h 8.1 (Berkeley) 6/2/93 * $FreeBSD: src/sys/sys/filedesc.h,v 1.19.2.5 2003/06/06 20:21:32 tegge Exp $ * $DragonFly: src/sys/sys/filedesc.h,v 1.8 2004/11/12 00:09:27 dillon Exp $ */ #ifndef _SYS_FILEDESC_H_ #define _SYS_FILEDESC_H_ #include /* * This structure is used for the management of descriptors. It may be * shared by multiple processes. * * A process is initially started out with NDFILE descriptors stored within * this structure, selected to be enough for typical applications based on * the historical limit of 20 open files (and the usage of descriptors by * shells). If these descriptors are exhausted, a larger descriptor table * may be allocated, up to a process' resource limit; the internal arrays * are then unused. The initial expansion is set to NDEXTENT; each time * it runs out, it is doubled until the resource limit is reached. NDEXTENT * should be selected to be the biggest multiple of OFILESIZE (see below) * that will fit in a power-of-two sized piece of memory. */ #define NDFILE 20 #define NDEXTENT 50 /* 250 bytes in 256-byte alloc. */ struct klist; struct namecache; struct filedesc { struct file **fd_ofiles; /* file structures for open files */ char *fd_ofileflags; /* per-process open file flags */ struct vnode *fd_cdir; /* current directory (phaseout) */ struct vnode *fd_rdir; /* root directory (phaseout) */ struct vnode *fd_jdir; /* jail root directory (phaseout) */ struct namecache *fd_ncdir; /* current directory */ struct namecache *fd_nrdir; /* root directory */ struct namecache *fd_njdir; /* jail directory */ int fd_nfiles; /* number of open files allocated */ u_short fd_lastfile; /* high-water mark of fd_ofiles */ u_short fd_freefile; /* approx. next free file */ u_short fd_cmask; /* mask for file creation */ u_short fd_refcnt; /* reference count */ int fd_knlistsize; /* size of knlist */ struct klist *fd_knlist; /* list of attached knotes */ u_long fd_knhashmask; /* size of knhash */ struct klist *fd_knhash; /* hash table for attached knotes */ int fd_holdleaderscount; /* block fdfree() for shared close() */ int fd_holdleaderswakeup; /* fdfree() needs wakeup */ }; /* * Basic allocation of descriptors: * one of the above, plus arrays for NDFILE descriptors. */ struct filedesc0 { struct filedesc fd_fd; /* * These arrays are used when the number of open files is * <= NDFILE, and are then pointed to by the pointers above. */ struct file *fd_dfiles[NDFILE]; char fd_dfileflags[NDFILE]; }; /* * Structure to keep track of (process leader, struct fildedesc) tuples. * Each process has a pointer to such a structure when detailed tracking * is needed. e.g. when rfork(RFPROC | RFMEM) causes a file descriptor * table to be shared by processes having different "p_leader" pointers * and thus distinct POSIX style locks. */ struct filedesc_to_leader { int fdl_refcount; /* references from struct proc */ int fdl_holdcount; /* temporary hold during closef */ int fdl_wakeup; /* fdfree() waits on closef() */ struct proc *fdl_leader; /* owner of POSIX locks */ /* Circular list */ struct filedesc_to_leader *fdl_prev; struct filedesc_to_leader *fdl_next; }; /* * Per-process open flags. */ #define UF_EXCLOSE 0x01 /* auto-close on exec */ #if 0 #define UF_MAPPED 0x02 /* mapped from device */ #endif /* * Storage required per open file descriptor. */ #define OFILESIZE (sizeof(struct file *) + sizeof(char)) /* * This structure that holds the information needed to send a SIGIO or * a SIGURG signal to a process or process group when new data arrives * on a device or socket. The structure is placed on an SLIST belonging * to the proc or pgrp so that the entire list may be revoked when the * process exits or the process group disappears. */ struct sigio { union { struct proc *siu_proc; /* process to receive SIGIO/SIGURG */ struct pgrp *siu_pgrp; /* process group to receive ... */ } sio_u; SLIST_ENTRY(sigio) sio_pgsigio; /* sigio's for process or group */ struct sigio **sio_myref; /* location of the pointer that holds * the reference to this structure */ struct ucred *sio_ucred; /* current credentials */ uid_t sio_ruid; /* real user id */ pid_t sio_pgid; /* pgid for signals */ }; #define sio_proc sio_u.siu_proc #define sio_pgrp sio_u.siu_pgrp SLIST_HEAD(sigiolst, sigio); #ifdef _KERNEL struct thread; struct proc; /* * Kernel global variables and routines. */ int dupfdopen (struct filedesc *, int, int, int, int); int fdalloc (struct proc *p, int want, int *result); int fdavail (struct proc *p, int n); int falloc (struct proc *p, struct file **resultfp, int *resultfd); int fsetfd (struct proc *p, struct file *fp, int *resultfd); void fsetcred (struct file *fp, struct ucred *cr); void ffree (struct file *); struct filedesc *fdinit (struct proc *p); struct filedesc *fdshare (struct proc *p); struct filedesc *fdcopy (struct proc *p); void fdfree (struct proc *p); int closef (struct file *fp, struct thread *td); void fdcloseexec (struct proc *p); int fdcheckstd (struct proc *p); struct file *holdfp (struct filedesc *fdp, int fd, int flag); int getvnode (struct filedesc *fdp, int fd, struct file **fpp); int fdissequential (struct file *); void fdsequential (struct file *, int); pid_t fgetown (struct sigio *); int fsetown (pid_t, struct sigio **); void funsetown (struct sigio *); void funsetownlst (struct sigiolst *); void setugidsafety (struct proc *p); struct filedesc_to_leader * filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct proc *leader); #endif #endif