/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1982, 1986, 1989, 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.
 */

#ifndef _SYS_FILE_H_
#define _SYS_FILE_H_

#ifndef _KERNEL
#include <sys/types.h> /* XXX */
#include <sys/fcntl.h>
#include <sys/unistd.h>
#else
#include <sys/errno.h>
#include <sys/_lock.h>
#include <sys/_mutex.h>
#include <sys/_null.h>
#include <sys/queue.h>
#include <sys/refcount.h>
#include <vm/vm.h>

struct filedesc;
struct proc;
struct stat;
struct thread;
struct uio;
struct knote;
struct vnode;
struct nameidata;

#endif /* _KERNEL */

#define DTYPE_NONE      0       /* not yet initialized */
#define DTYPE_VNODE     1       /* file */
#define DTYPE_SOCKET    2       /* communications endpoint */
#define DTYPE_PIPE      3       /* pipe */
#define DTYPE_FIFO      4       /* fifo (named pipe) */
#define DTYPE_KQUEUE    5       /* event queue */
#define DTYPE_CRYPTO    6       /* crypto */
#define DTYPE_MQUEUE    7       /* posix message queue */
#define DTYPE_SHM       8       /* swap-backed shared memory */
#define DTYPE_SEM       9       /* posix semaphore */
#define DTYPE_PTS       10      /* pseudo teletype master device */
#define DTYPE_DEV       11      /* Device specific fd type */
#define DTYPE_PROCDESC  12      /* process descriptor */
#define DTYPE_EVENTFD   13      /* eventfd */
#define DTYPE_TIMERFD   14      /* timerfd */
#define DTYPE_INOTIFY   15      /* inotify descriptor */
#define DTYPE_JAILDESC  16      /* jail descriptor */

#ifdef _KERNEL

struct file;
struct filecaps;
struct kaiocb;
struct kinfo_file;
struct ucred;

#define FOF_OFFSET      0x01    /* Use the offset in uio argument */
#define FOF_NOLOCK      0x02    /* Do not take FOFFSET_LOCK */
#define FOF_NEXTOFF_R   0x04    /* Also update f_nextoff[UIO_READ] */
#define FOF_NEXTOFF_W   0x08    /* Also update f_nextoff[UIO_WRITE] */
#define FOF_NOUPDATE    0x10    /* Do not update f_offset */
off_t foffset_lock(struct file *fp, int flags);
void foffset_lock_pair(struct file *fp1, off_t *off1p, struct file *fp2,
    off_t *off2p, int flags);
void foffset_lock_uio(struct file *fp, struct uio *uio, int flags);
void foffset_unlock(struct file *fp, off_t val, int flags);
void foffset_unlock_uio(struct file *fp, struct uio *uio, int flags);
void fsetfl_lock(struct file *fp);
void fsetfl_unlock(struct file *fp);

static inline off_t
foffset_get(struct file *fp)
{

        return (foffset_lock(fp, FOF_NOLOCK));
}

typedef int fo_rdwr_t(struct file *fp, struct uio *uio,
                    struct ucred *active_cred, int flags,
                    struct thread *td);
typedef int fo_truncate_t(struct file *fp, off_t length,
                    struct ucred *active_cred, struct thread *td);
typedef int fo_ioctl_t(struct file *fp, u_long com, void *data,
                    struct ucred *active_cred, struct thread *td);
typedef int fo_poll_t(struct file *fp, int events,
                    struct ucred *active_cred, struct thread *td);
typedef int fo_kqfilter_t(struct file *fp, struct knote *kn);
typedef int fo_stat_t(struct file *fp, struct stat *sb,
                    struct ucred *active_cred);
typedef int fo_close_t(struct file *fp, struct thread *td);
typedef void fo_fdclose_t(struct file *fp, int fd, struct thread *td);
typedef int fo_chmod_t(struct file *fp, mode_t mode,
                    struct ucred *active_cred, struct thread *td);
typedef int fo_chown_t(struct file *fp, uid_t uid, gid_t gid,
                    struct ucred *active_cred, struct thread *td);
typedef int fo_sendfile_t(struct file *fp, int sockfd, struct uio *hdr_uio,
                    struct uio *trl_uio, off_t offset, size_t nbytes,
                    off_t *sent, int flags, struct thread *td);
typedef int fo_seek_t(struct file *fp, off_t offset, int whence,
                    struct thread *td);
typedef int fo_fill_kinfo_t(struct file *fp, struct kinfo_file *kif,
                    struct filedesc *fdp);
typedef int fo_mmap_t(struct file *fp, vm_map_t map, vm_offset_t *addr,
                    vm_size_t size, vm_prot_t prot, vm_prot_t cap_maxprot,
                    int flags, vm_ooffset_t foff, struct thread *td);
typedef int fo_aio_queue_t(struct file *fp, struct kaiocb *job);
typedef int fo_add_seals_t(struct file *fp, int flags);
typedef int fo_get_seals_t(struct file *fp, int *flags);
typedef int fo_fallocate_t(struct file *fp, off_t offset, off_t len,
                    struct thread *td);
typedef int fo_fspacectl_t(struct file *fp, int cmd,
                    off_t *offset, off_t *length, int flags,
                    struct ucred *active_cred, struct thread *td);
typedef int fo_cmp_t(struct file *fp, struct file *fp1, struct thread *td);
typedef int fo_fork_t(struct filedesc *fdp, struct file *fp, struct file **fp1,
                    struct proc *p1, struct thread *td);
typedef int fo_spare_t(struct file *fp);
typedef int fo_flags_t;

struct fileops {
        fo_rdwr_t       *fo_read;
        fo_rdwr_t       *fo_write;
        fo_truncate_t   *fo_truncate;
        fo_ioctl_t      *fo_ioctl;
        fo_poll_t       *fo_poll;
        fo_kqfilter_t   *fo_kqfilter;
        fo_stat_t       *fo_stat;
        fo_close_t      *fo_close;
        fo_fdclose_t    *fo_fdclose;
        fo_chmod_t      *fo_chmod;
        fo_chown_t      *fo_chown;
        fo_sendfile_t   *fo_sendfile;
        fo_seek_t       *fo_seek;
        fo_fill_kinfo_t *fo_fill_kinfo;
        fo_mmap_t       *fo_mmap;
        fo_aio_queue_t  *fo_aio_queue;
        fo_add_seals_t  *fo_add_seals;
        fo_get_seals_t  *fo_get_seals;
        fo_fallocate_t  *fo_fallocate;
        fo_fspacectl_t  *fo_fspacectl;
        fo_cmp_t        *fo_cmp;
        fo_fork_t       *fo_fork;
        fo_spare_t      *fo_spares[8];  /* Spare slots */
        fo_flags_t      fo_flags;       /* DFLAG_* below */
};

#define DFLAG_PASSABLE  0x01    /* may be passed via unix sockets. */
#define DFLAG_SEEKABLE  0x02    /* seekable / nonsequential */
#define DFLAG_FORK      0x04    /* copy on fork */
#endif /* _KERNEL */

#if defined(_KERNEL) || defined(_WANT_FILE)
/*
 * Kernel descriptor table.
 * One entry for each open kernel vnode and socket.
 *
 * Below is the list of locks that protects members in struct file.
 *
 * (a) f_vnode lock required (shared allows both reads and writes)
 * (f) updated with atomics and blocking on sleepq
 * (d) cdevpriv_mtx
 * none not locked
 */

#if __BSD_VISIBLE
struct fadvise_info {
        int             fa_advice;      /* (f) FADV_* type. */
        off_t           fa_start;       /* (f) Region start. */
        off_t           fa_end;         /* (f) Region end. */
};

struct file {
        volatile u_int  f_flag;         /* see fcntl.h */
        volatile u_int  f_count;        /* reference count */
        void            *f_data;        /* file descriptor specific data */
        const struct fileops *f_ops;    /* File operations */
        struct vnode    *f_vnode;       /* NULL or applicable vnode */
        struct ucred    *f_cred;        /* associated credentials. */
        short           f_type;         /* descriptor type */
        short           f_vflags;       /* (f) Sleep lock flags for members */
        /*
         *  DTYPE_VNODE specific fields.
         */
        union {
                int16_t f_seqcount[2];  /* (a) Count of seq. reads and writes. */
                int     f_pipegen;
        };
        off_t           f_nextoff[2];   /* next expected read/write offset. */
        union {
                struct cdev_privdata *fvn_cdevpriv;
                                        /* (d) Private data for the cdev. */
                struct fadvise_info *fvn_advice;
        } f_vnun;
        /*
         *  DFLAG_SEEKABLE specific fields
         */
        off_t           f_offset;
};

#define f_cdevpriv      f_vnun.fvn_cdevpriv
#define f_advice        f_vnun.fvn_advice

#define FILE_V_FOFFSET_LOCKED           0x0001
#define FILE_V_FOFFSET_LOCK_WAITING     0x0002
#define FILE_V_SETFL_LOCKED             0x0004
#define FILE_V_SETFL_LOCK_WAITING       0x0008
#endif /* __BSD_VISIBLE */

#endif /* _KERNEL || _WANT_FILE */

/*
 * Userland version of struct file, for sysctl
 */
#if __BSD_VISIBLE
struct xfile {
        ksize_t xf_size;        /* size of struct xfile */
        pid_t   xf_pid;         /* owning process */
        uid_t   xf_uid;         /* effective uid of owning process */
        int     xf_fd;          /* descriptor number */
        int     _xf_int_pad1;
        kvaddr_t xf_file;       /* address of struct file */
        short   xf_type;        /* descriptor type */
        short   _xf_short_pad1;
        int     xf_count;       /* reference count */
        int     xf_msgcount;    /* references from message queue */
        int     _xf_int_pad2;
        off_t   xf_offset;      /* file offset */
        kvaddr_t xf_data;       /* file descriptor specific data */
        kvaddr_t xf_vnode;      /* vnode pointer */
        u_int   xf_flag;        /* flags (see fcntl.h) */
        int     _xf_int_pad3;
        int64_t _xf_int64_pad[6];
};
#endif /* __BSD_VISIBLE */

#ifdef _KERNEL

extern const struct fileops vnops;
extern const struct fileops badfileops;
extern const struct fileops path_fileops;
extern const struct fileops socketops;
extern int maxfiles;            /* kernel limit on number of open files */
extern int maxfilesperproc;     /* per process limit on number of open files */

int fget(struct thread *td, int fd, const cap_rights_t *rightsp,
    struct file **fpp);
int fget_mmap(struct thread *td, int fd, const cap_rights_t *rightsp,
    vm_prot_t *maxprotp, struct file **fpp);
int fget_read(struct thread *td, int fd, const cap_rights_t *rightsp,
    struct file **fpp);
int fget_write(struct thread *td, int fd, const cap_rights_t *rightsp,
    struct file **fpp);
int fget_fcntl(struct thread *td, int fd, const cap_rights_t *rightsp,
    int needfcntl, struct file **fpp);
int _fdrop(struct file *fp, struct thread *td);
int fget_remote(struct thread *td, struct proc *p, int fd, struct file **fpp);
int fget_remote_foreach(struct thread *td, struct proc *p,
    int (*fn)(struct proc *, int, struct file *, void *), void *arg);

fo_rdwr_t       invfo_rdwr;
fo_truncate_t   invfo_truncate;
fo_ioctl_t      invfo_ioctl;
fo_poll_t       invfo_poll;
fo_kqfilter_t   invfo_kqfilter;
fo_chmod_t      invfo_chmod;
fo_chown_t      invfo_chown;
fo_sendfile_t   invfo_sendfile;
fo_stat_t       vn_statfile;
fo_sendfile_t   vn_sendfile;
fo_seek_t       vn_seek;
fo_fill_kinfo_t vn_fill_kinfo;
fo_kqfilter_t   vn_kqfilter_opath;
int vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif);
int file_kcmp_generic(struct file *fp1, struct file *fp2, struct thread *td);

void finit(struct file *, u_int, short, void *, const struct fileops *);
void finit_vnode(struct file *, u_int, void *, const struct fileops *);
int fgetvp(struct thread *td, int fd, const cap_rights_t *rightsp,
    struct vnode **vpp);
int fgetvp_exec(struct thread *td, int fd, const cap_rights_t *rightsp,
    struct vnode **vpp);
int fgetvp_rights(struct thread *td, int fd, const cap_rights_t *needrightsp,
    struct filecaps *havecaps, struct vnode **vpp);
int fgetvp_read(struct thread *td, int fd, const cap_rights_t *rightsp,
    struct vnode **vpp);
int fgetvp_write(struct thread *td, int fd, const cap_rights_t *rightsp,
    struct vnode **vpp);
int fgetvp_lookup_smr(struct nameidata *ndp, struct vnode **vpp, int *flagsp);
int fgetvp_lookup(struct nameidata *ndp, struct vnode **vpp);

static __inline __result_use_check bool
fhold(struct file *fp)
{
        return (refcount_acquire_checked(&fp->f_count));
}

#define fdrop(fp, td)           ({                              \
        struct file *_fp;                                       \
        int _error;                                             \
                                                                \
        _error = 0;                                             \
        _fp = (fp);                                             \
        if (__predict_false(refcount_release(&_fp->f_count)))   \
                _error = _fdrop(_fp, td);                       \
        _error;                                                 \
})

#define fdrop_close(fp, td)             ({                      \
        struct file *_fp;                                       \
        int _error;                                             \
                                                                \
        _error = 0;                                             \
        _fp = (fp);                                             \
        if (__predict_true(refcount_release(&_fp->f_count)))    \
                _error = _fdrop(_fp, td);                       \
        _error;                                                 \
})

static __inline fo_rdwr_t       fo_read;
static __inline fo_rdwr_t       fo_write;
static __inline fo_truncate_t   fo_truncate;
static __inline fo_ioctl_t      fo_ioctl;
static __inline fo_poll_t       fo_poll;
static __inline fo_kqfilter_t   fo_kqfilter;
static __inline fo_stat_t       fo_stat;
static __inline fo_close_t      fo_close;
static __inline fo_chmod_t      fo_chmod;
static __inline fo_chown_t      fo_chown;
static __inline fo_sendfile_t   fo_sendfile;

static __inline int
fo_read(struct file *fp, struct uio *uio, struct ucred *active_cred,
    int flags, struct thread *td)
{

        return ((*fp->f_ops->fo_read)(fp, uio, active_cred, flags, td));
}

static __inline int
fo_write(struct file *fp, struct uio *uio, struct ucred *active_cred,
    int flags, struct thread *td)
{

        return ((*fp->f_ops->fo_write)(fp, uio, active_cred, flags, td));
}

static __inline int
fo_truncate(struct file *fp, off_t length, struct ucred *active_cred,
    struct thread *td)
{

        return ((*fp->f_ops->fo_truncate)(fp, length, active_cred, td));
}

static __inline int
fo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
    struct thread *td)
{

        return ((*fp->f_ops->fo_ioctl)(fp, com, data, active_cred, td));
}

static __inline int
fo_poll(struct file *fp, int events, struct ucred *active_cred,
    struct thread *td)
{

        return ((*fp->f_ops->fo_poll)(fp, events, active_cred, td));
}

static __inline int
fo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred)
{

        return ((*fp->f_ops->fo_stat)(fp, sb, active_cred));
}

static __inline int
fo_close(struct file *fp, struct thread *td)
{

        return ((*fp->f_ops->fo_close)(fp, td));
}

static __inline int
fo_kqfilter(struct file *fp, struct knote *kn)
{

        return ((*fp->f_ops->fo_kqfilter)(fp, kn));
}

static __inline int
fo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
    struct thread *td)
{

        return ((*fp->f_ops->fo_chmod)(fp, mode, active_cred, td));
}

static __inline int
fo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
    struct thread *td)
{

        return ((*fp->f_ops->fo_chown)(fp, uid, gid, active_cred, td));
}

static __inline int
fo_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio,
    struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags,
    struct thread *td)
{

        return ((*fp->f_ops->fo_sendfile)(fp, sockfd, hdr_uio, trl_uio, offset,
            nbytes, sent, flags, td));
}

static __inline int
fo_seek(struct file *fp, off_t offset, int whence, struct thread *td)
{

        return ((*fp->f_ops->fo_seek)(fp, offset, whence, td));
}

static __inline int
fo_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
{

        return ((*fp->f_ops->fo_fill_kinfo)(fp, kif, fdp));
}

static __inline int
fo_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
    vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
    struct thread *td)
{

        if (fp->f_ops->fo_mmap == NULL)
                return (ENODEV);
        return ((*fp->f_ops->fo_mmap)(fp, map, addr, size, prot, cap_maxprot,
            flags, foff, td));
}

static __inline int
fo_aio_queue(struct file *fp, struct kaiocb *job)
{

        return ((*fp->f_ops->fo_aio_queue)(fp, job));
}

static __inline int
fo_add_seals(struct file *fp, int seals)
{

        if (fp->f_ops->fo_add_seals == NULL)
                return (EINVAL);
        return ((*fp->f_ops->fo_add_seals)(fp, seals));
}

static __inline int
fo_get_seals(struct file *fp, int *seals)
{

        if (fp->f_ops->fo_get_seals == NULL)
                return (EINVAL);
        return ((*fp->f_ops->fo_get_seals)(fp, seals));
}

static __inline int
fo_fallocate(struct file *fp, off_t offset, off_t len, struct thread *td)
{

        if (fp->f_ops->fo_fallocate == NULL)
                return (ENODEV);
        return ((*fp->f_ops->fo_fallocate)(fp, offset, len, td));
}

static __inline int
fo_fspacectl(struct file *fp, int cmd, off_t *offset, off_t *length,
    int flags, struct ucred *active_cred, struct thread *td)
{

        if (fp->f_ops->fo_fspacectl == NULL)
                return (ENODEV);
        return ((*fp->f_ops->fo_fspacectl)(fp, cmd, offset, length, flags,
            active_cred, td));
}

static __inline int
fo_cmp(struct file *fp1, struct file *fp2, struct thread *td)
{

        if (fp1->f_ops->fo_cmp == NULL)
                return (ENODEV);
        return ((*fp1->f_ops->fo_cmp)(fp1, fp2, td));
}

#endif /* _KERNEL */

#endif /* !SYS_FILE_H */