/* * 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. 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 $ */ #ifndef _SYS_FILEDESC_H_ #define _SYS_FILEDESC_H_ #ifndef _SYS_TYPES_H_ #include <sys/types.h> #endif #ifndef _SYS_QUEUE_H_ #include <sys/queue.h> #endif #ifndef _SYS_SPINLOCK_H_ #include <sys/spinlock.h> #endif #ifndef _SYS_NAMECACHE_H_ #include <sys/namecache.h> #endif /* * 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) and the constraint of being one less than a power of 2. * If these descriptors are exhausted, a larger descriptor table * may be allocated, up to a process' resource limit; the internal arrays * are then unused. Each time the file table runs out, it is doubled until * the resource limit is reached. */ #define NDFILE 15 /* must be of the form 2^n - 1 */ #define NTDCACHEFD 4 /* max td's caching same fd */ struct file; struct klist; struct fdcache; typedef char fileflags_t; struct fdnode { struct file *fp; fileflags_t fileflags; char isfull; char iterator; char reserved; /* descriptor has been reserved */ int allocated; /* subtree allocation count */ struct fdcache *tdcache[NTDCACHEFD]; }; struct filedesc { struct fdnode *fd_files; /* file structures for open files */ struct vnode *fd_cdir; /* current directory (phaseout) */ struct vnode *fd_rdir; /* root directory (phaseout) */ struct vnode *fd_jdir; /* jail root directory (phaseout) */ struct nchandle fd_ncdir; /* current directory */ struct nchandle fd_nrdir; /* root directory */ struct nchandle fd_njdir; /* jail directory */ int fd_nfiles; /* number of open files allocated */ int fd_lastfile; /* high-water mark of fd_files */ int fd_freefile; /* approx. next free file */ int fd_cmask; /* mask for file creation */ int fd_refcnt; /* reference count */ int fd_softrefs; /* softrefs to prevent destruction */ int fd_holdleaderscount; /* block fdfree() for shared close() */ int fd_holdleaderswakeup; /* fdfree() needs wakeup */ int fd_closedcounter; /* detect close() */ struct spinlock fd_spin; struct fdnode fd_builtin_files[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 */ #define UF_FOCLOSE 0x02 /* auto-close on fork */ /* * 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 */ 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 /* Type flags for kern_dup(). */ #define DUP_FIXED 0x1 /* Copy to specific fd even if in use */ #define DUP_VARIABLE 0x2 /* Copy fd to an unused fd */ #define DUP_CLOEXEC 0x4 /* Set fd close on exec flag */ #define DUP_FCNTL 0x8 /* Set for F_DUPFD, F_DUPFD_CLO{EXEC,FORK} */ #define DUP_CLOFORK 0x10 /* Set fd close on fork flag */ struct thread; struct proc; struct lwp; /* * Kernel global variables and routines. */ int fdalloc (struct proc *p, int want, int *result); int fdavail (struct proc *p, int n); int falloc (struct lwp *lp, struct file **resultfp, int *resultfd); void fsetfd (struct filedesc *fdp, struct file *fp, int fd); int fgetfdflags(struct filedesc *fdp, int fd, int *flagsp); int faddfdflags(struct filedesc *fdp, int fd, int add_flags); int fsetfdflags(struct filedesc *fdp, int fd, int set_flags); int fclrfdflags(struct filedesc *fdp, int fd, int rem_flags); void fsetcred (struct file *fp, struct ucred *cr); void fdinit_bootstrap(struct proc *p0, struct filedesc *fdp0, int cmask); struct filedesc *fdinit (struct proc *p); struct filedesc *fdshare (struct proc *p); int fdcopy (struct proc *p, struct filedesc **fpp); void fdfree (struct proc *p, struct filedesc *repl); int fdrevoke(void *f_data, short f_type, struct ucred *cred); int closef (struct file *fp, struct proc *p); void fdcloseexec (struct proc *p); int fdcheckstd (struct lwp *lp); struct file *holdfp (struct thread *td, int fd, int flag); struct file *holdfp_fdp (struct filedesc *fdp, int fd, int flag); struct file *holdfp_fdp_locked (struct filedesc *fdp, int fd, int flag); int holdsock (struct thread *td, int fdes, struct file **fpp); int holdvnode (struct thread *td, int fd, struct file **fpp); int holdvnode2 (struct thread *td, int fd, struct file **fpp, char *fflagsp); void dropfp(struct thread *td, int fd, struct file *fp); 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); void allfiles_scan_exclusive(int (*callback)(struct file *, void *), void *data); void fexitcache(struct thread *td); struct filedesc_to_leader * filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct proc *leader); #endif #endif
