trunk/cdrecord/fifo.c

/* @(#)fifo.c   1.49 06/02/08 Copyright 1989,1997-2006 J. Schilling */
#ifndef lint
static  char sccsid[] =
        "@(#)fifo.c     1.49 06/02/08 Copyright 1989,1997-2006 J. Schilling";
#endif
/*
 *      A "fifo" that uses shared memory between two processes
 *
 *      The actual code is a mixture of borrowed code from star's fifo.c
 *      and a proposal from Finn Arne Gangstad <finnag@guardian.no>
 *      who had the idea to use a ring buffer to handle average size chunks.
 *
 *      Copyright (c) 1989,1997-2006 J. Schilling
 */
/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; see the file COPYING.  If not, write to the Free Software
 * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#ifndef DEBUG
#define DEBUG
#endif
/*#define       XDEBUG*/
#include <mconfig.h>

  /* XXX Force use of FIFO untill we fixed the detection */
#ifndef FIFO
#define FIFO
#endif

#if     defined(HAVE_OS_H) && \
        defined(HAVE_CLONE_AREA) && defined(HAVE_CREATE_AREA) && \
        defined(HAVE_DELETE_AREA)
#include <OS.h>
#       define  HAVE_BEOS_AREAS /* BeOS/Zeta */
#endif
#if     !defined(HAVE_SMMAP) && !defined(HAVE_USGSHM) && \
        !defined(HAVE_DOSALLOCSHAREDMEM) && !defined(HAVE_BEOS_AREAS)
#undef  FIFO                    /* We cannot have a FIFO on this platform */
#endif
#if     !defined(HAVE_FORK)
#undef  FIFO                    /* We cannot have a FIFO on this platform */
#endif
#ifdef  FIFO
#if !defined(USE_MMAP) && !defined(USE_USGSHM)
#define USE_MMAP
#endif
#ifndef HAVE_SMMAP
#       undef   USE_MMAP
#       define  USE_USGSHM      /* now SYSV shared memory is the default*/
#endif
#ifdef  USE_MMAP                /* Only want to have one implementation */
#       undef   USE_USGSHM      /* mmap() is preferred                  */
#endif

#ifdef  HAVE_DOSALLOCSHAREDMEM  /* This is for OS/2 */
#       undef   USE_MMAP
#       undef   USE_USGSHM
#       define  USE_OS2SHM
#endif

#ifdef  HAVE_BEOS_AREAS         /* This is for BeOS/Zeta */
#       undef   USE_MMAP
#       undef   USE_USGSHM
#       undef   USE_OS2SHM
#       define  USE_BEOS_AREAS
#endif

#include <stdio.h>
#include <stdxlib.h>
#include <unixstd.h>    /* includes <sys/types.h> */
#include <utypes.h>
#include <fctldefs.h>
#if defined(HAVE_SMMAP) && defined(USE_MMAP)
#include <mmapdefs.h>
#endif
#include <waitdefs.h>
#include <standard.h>
#include <errno.h>
#include <signal.h>
#include <libport.h>
#include <schily.h>

#include "cdrecord.h"
#include "xio.h"

#ifdef DEBUG
#ifdef XDEBUG
FILE    *ef;
#define USDEBUG1        if (debug) {if (s == owner_reader) fprintf(ef, "r"); else fprintf(ef, "w"); fflush(ef); }
#define USDEBUG2        if (debug) {if (s == owner_reader) fprintf(ef, "R"); else fprintf(ef, "W"); fflush(ef); }
#else
#define USDEBUG1
#define USDEBUG2
#endif
#define EDEBUG(a)       if (debug) error a
#else
#define EDEBUG(a)
#define USDEBUG1
#define USDEBUG2
#endif

#define palign(x, a)    (((char *)(x)) + ((a) - 1 - (((UIntptr_t)((x)-1))%(a))))

typedef enum faio_owner {
        owner_none,             /* Unused in real life                      */
        owner_writer,           /* owned by process that writes into FIFO   */
        owner_faio,             /* Intermediate state when buf still in use */
        owner_reader            /* owned by process that reads from FIFO    */
} fowner_t;

char    *onames[] = {
        "none",
        "writer",
        "faio",
        "reader",
};

typedef struct faio {
        int     len;
        volatile fowner_t owner;
        volatile int users;
        short   fd;
        short   saved_errno;
        char    *bufp;
} faio_t;

struct faio_stats {
        long    puts;
        long    gets;
        long    empty;
        long    full;
        long    done;
        long    cont_low;
        int     users;
} *sp;

#define MIN_BUFFERS     3

#define MSECS   1000
#define SECS    (1000*MSECS)

/*
 * Note: WRITER_MAXWAIT & READER_MAXWAIT need to be greater than the SCSI
 * timeout for commands that write to the media. This is currently 200s
 * if we are in SAO mode.
 */
/* microsecond delay between each buffer-ready probe by writing process */
#define WRITER_DELAY    (20*MSECS)
#define WRITER_MAXWAIT  (240*SECS)      /* 240 seconds max wait for data */

/* microsecond delay between each buffer-ready probe by reading process */
#define READER_DELAY    (80*MSECS)
#define READER_MAXWAIT  (240*SECS)      /* 240 seconds max wait for reader */

LOCAL   char    *buf;
LOCAL   char    *bufbase;
LOCAL   char    *bufend;
LOCAL   long    buflen;                 /* The size of the FIFO buffer */

extern  int     debug;
extern  int     lverbose;

EXPORT  void    init_fifo       __PR((long));
#ifdef  USE_MMAP
LOCAL   char    *mkshare        __PR((int size));
#endif
#ifdef  USE_USGSHM
LOCAL   char    *mkshm          __PR((int size));
#endif
#ifdef  USE_OS2SHM
LOCAL   char    *mkos2shm       __PR((int size));
#endif
#ifdef  USE_BEOS_AREAS
LOCAL   char    *mkbeosshm      __PR((int size));
LOCAL   void    beosshm_child   __PR((void));
#endif

EXPORT  BOOL    init_faio       __PR((track_t *trackp, int));
EXPORT  BOOL    await_faio      __PR((void));
EXPORT  void    kill_faio       __PR((void));
EXPORT  int     wait_faio       __PR((void));
LOCAL   void    faio_reader     __PR((track_t *trackp));
LOCAL   void    faio_read_track __PR((track_t *trackp));
LOCAL   void    faio_wait_on_buffer __PR((faio_t *f, fowner_t s,
                                        unsigned long delay,
                                        unsigned long max_wait));
LOCAL   int     faio_read_segment __PR((int fd, faio_t *f, track_t *track, long secno, int len));
LOCAL   faio_t  *faio_ref       __PR((int n));
EXPORT  int     faio_read_buf   __PR((int f, char *bp, int size));
EXPORT  int     faio_get_buf    __PR((int f, char **bpp, int size));
EXPORT  void    fifo_stats      __PR((void));
EXPORT  int     fifo_percent    __PR((BOOL addone));


EXPORT void
init_fifo(fs)
        long    fs;
{
        int     pagesize;

        if (fs == 0L)
                return;

#ifdef  _SC_PAGESIZE
        pagesize = sysconf(_SC_PAGESIZE);
#else
        pagesize = getpagesize();
#endif
        buflen = roundup(fs, pagesize) + pagesize;
        EDEBUG(("fs: %ld buflen: %ld\n", fs, buflen));

#if     defined(USE_MMAP)
        buf = mkshare(buflen);
#endif
#if     defined(USE_USGSHM)
        buf = mkshm(buflen);
#endif
#if     defined(USE_OS2SHM)
        buf = mkos2shm(buflen);
#endif
#if     defined(USE_BEOS_AREAS)
        buf = mkbeosshm(buflen);
#endif

        bufbase = buf;
        bufend = buf + buflen;
        EDEBUG(("buf: %p bufend: %p, buflen: %ld\n", buf, bufend, buflen));
        buf = palign(buf, pagesize);
        buflen -= buf - bufbase;
        EDEBUG(("buf: %p bufend: %p, buflen: %ld (align %ld)\n", buf, bufend, buflen, (long)(buf - bufbase)));

        /*
         * Dirty the whole buffer. This can die with various signals if
         * we're trying to lock too much memory
         */
        fillbytes(buf, buflen, '\0');

#ifdef  XDEBUG
        if (debug)
                ef = fopen("/tmp/ef", "w");
#endif
}

#ifdef  USE_MMAP
LOCAL char *
mkshare(size)
        int     size;
{
        int     f;
        char    *addr;

#ifdef  MAP_ANONYMOUS   /* HP/UX */
        f = -1;
        addr = mmap(0, mmap_sizeparm(size),
                        PROT_READ|PROT_WRITE, MAP_SHARED|MAP_ANONYMOUS, f, 0);
#else
        if ((f = open("/dev/zero", O_RDWR)) < 0)
                comerr("Cannot open '/dev/zero'.\n");
        addr = mmap(0, mmap_sizeparm(size),
                        PROT_READ|PROT_WRITE, MAP_SHARED, f, 0);
#endif
        if (addr == (char *)-1)
                comerr("Cannot get mmap for %d Bytes on /dev/zero.\n", size);
        if (f >= 0)
                close(f);

        if (debug) errmsgno(EX_BAD, "shared memory segment attached at: %p size %d\n",
                                (void *)addr, size);

        return (addr);
}
#endif

#ifdef  USE_USGSHM
#include <sys/ipc.h>
#include <sys/shm.h>
LOCAL char *
mkshm(size)
        int     size;
{
        int     id;
        char    *addr;
        /*
         * Unfortunately, a declaration of shmat() is missing in old
         * implementations such as AT&T SVr0 and SunOS.
         * We cannot add this definition here because the return-type
         * changed on newer systems.
         *
         * We will get a warning like this:
         *
         * warning: assignment of pointer from integer lacks a cast
         * or
         * warning: illegal combination of pointer and integer, op =
         */
/*      extern  char *shmat();*/

        if ((id = shmget(IPC_PRIVATE, size, IPC_CREAT|0600)) == -1)
                comerr("shmget failed\n");

        if (debug) errmsgno(EX_BAD, "shared memory segment allocated: %d\n", id);

        if ((addr = shmat(id, (char *)0, 0600)) == (char *)-1)
                comerr("shmat failed\n");

        if (debug) errmsgno(EX_BAD, "shared memory segment attached at: %p size %d\n",
                                (void *)addr, size);

        if (shmctl(id, IPC_RMID, 0) < 0)
                comerr("shmctl failed to detach shared memory segment\n");

#ifdef  SHM_LOCK
        /*
         * Although SHM_LOCK is standard, it seems that all versions of AIX
         * ommit this definition.
         */
        if (shmctl(id, SHM_LOCK, 0) < 0)
                comerr("shmctl failed to lock shared memory segment\n");
#endif

        return (addr);
}
#endif

#ifdef  USE_OS2SHM
LOCAL char *
mkos2shm(size)
        int     size;
{
        char    *addr;

        /*
         * The OS/2 implementation of shm (using shm.dll) limits the size of one shared
         * memory segment to 0x3fa000 (aprox. 4MBytes). Using OS/2 native API we have
         * no such restriction so I decided to use it allowing fifos of arbitrary size.
         */
        if (DosAllocSharedMem(&addr, NULL, size, 0X100L | 0x1L | 0x2L | 0x10L))
                comerr("DosAllocSharedMem() failed\n");

        if (debug) errmsgno(EX_BAD, "shared memory allocated attached at: %p size %d\n",
                                (void *)addr, size);

        return (addr);
}
#endif

#ifdef  USE_BEOS_AREAS
LOCAL   area_id faio_aid;
LOCAL   void    *faio_addr;
LOCAL   char    faio_name[32];

LOCAL char *
mkbeosshm(size)
        int     size;
{
        snprintf(faio_name, sizeof (faio_name), "cdrecord FIFO %lld",
                (Llong)getpid());

        faio_aid = create_area(faio_name, &faio_addr,
                        B_ANY_ADDRESS,
                        size,
                        B_NO_LOCK, B_READ_AREA|B_WRITE_AREA);
        if (faio_addr == NULL) {
                comerrno(faio_aid,
                        "Cannot get create_area for %d Bytes FIFO.\n", size);
        }
        if (debug) errmsgno(EX_BAD, "shared memory allocated attached at: %p size %d\n",
                                (void *)faio_addr, size);
        return (faio_addr);
}

LOCAL void
beosshm_child()
{
        /*
         * Delete the area created by fork that is copy-on-write.
         */
        delete_area(area_for(faio_addr));
        /*
         * Clone (share) the original one.
         */
        faio_aid = clone_area(faio_name, &faio_addr,
                        B_ANY_ADDRESS, B_READ_AREA|B_WRITE_AREA,
                        faio_aid);
        if (bufbase != faio_addr) {
                errmsgno(EX_BAD, "Panic FIFO addr.\n");
                return (FALSE);
        }
}
#endif

LOCAL   int     faio_buffers;
LOCAL   int     faio_buf_size;
LOCAL   int     buf_idx = 0;            /* Initialize to fix an Amiga bug   */
LOCAL   int     buf_idx_reader = 0;     /* Separate var to allow vfork()    */
                                        /* buf_idx_reader is for the process */
                                        /* that fills the FIFO              */
LOCAL   pid_t   faio_pid;
LOCAL   BOOL    faio_didwait;

#ifdef AMIGA
/*
 * On Amiga fork will be replaced by the speciall vfork() like call ix_vfork,
 * which lets the parent asleep. The child process later wakes up the parent
 * process by calling ix_fork_resume().
 */
#define fork()           ix_vfork()
#define __vfork_resume() ix_vfork_resume()

#else   /* !AMIGA */
#define __vfork_resume()
#endif


/*#define       faio_ref(n)     (&((faio_t *)buf)[n])*/


EXPORT BOOL
init_faio(trackp, bufsize)
        track_t *trackp;
        int     bufsize;        /* The size of a single transfer buffer */
{
        int     n;
        faio_t  *f;
        int     pagesize;
        char    *base;

        if (buflen == 0L)
                return (FALSE);

#ifdef  _SC_PAGESIZE
        pagesize = sysconf(_SC_PAGESIZE);
#else
        pagesize = getpagesize();
#endif

        faio_buf_size = bufsize;
        f = (faio_t *)buf;

        /*
         * Compute space for buffer headers.
         * Round bufsize up to pagesize to make each FIFO segment
         * properly page aligned.
         */
        bufsize = roundup(bufsize, pagesize);
        faio_buffers = (buflen - sizeof (*sp)) / bufsize;
        EDEBUG(("bufsize: %d buffers: %d hdrsize %ld\n", bufsize, faio_buffers, (long)faio_buffers * sizeof (struct faio)));

        /*
         * Reduce buffer space by header space.
         */
        n = sizeof (*sp) + faio_buffers * sizeof (struct faio);
        n = roundup(n, pagesize);
        faio_buffers = (buflen-n) / bufsize;
        EDEBUG(("bufsize: %d buffers: %d hdrsize %ld\n", bufsize, faio_buffers, (long)faio_buffers * sizeof (struct faio)));

        if (faio_buffers < MIN_BUFFERS) {
                errmsgno(EX_BAD,
                        "write-buffer too small, minimum is %dk. Disabling.\n",
                                                MIN_BUFFERS*bufsize/1024);
                return (FALSE);
        }

        if (debug)
                printf("Using %d buffers of %d bytes.\n", faio_buffers, faio_buf_size);

        f = (faio_t *)buf;
        base = buf + roundup(sizeof (*sp) + faio_buffers * sizeof (struct faio),
                                pagesize);

        for (n = 0; n < faio_buffers; n++, f++, base += bufsize) {
                /* Give all the buffers to the file reader process */
                f->owner = owner_writer;
                f->users = 0;
                f->bufp = base;
                f->fd = -1;
        }
        sp = (struct faio_stats *)f;    /* point past headers */
        sp->gets = sp->puts = sp->done = 0L;
        sp->users = 1;

        faio_pid = fork();
        if (faio_pid < 0)
                comerr("fork(2) failed");

        if (faio_pid == 0) {
                /*
                 * child (background) process that fills the FIFO.
                 */
                raisepri(1);            /* almost max priority */

#ifdef USE_OS2SHM
                DosGetSharedMem(buf, 3); /* PAG_READ|PAG_WRITE */
#endif
#ifdef  USE_BEOS_AREAS
                beosshm_child();
#endif
                /* Ignoring SIGALRM cures the SCO usleep() bug */
/*              signal(SIGALRM, SIG_IGN);*/
                __vfork_resume();       /* Needed on some platforms */
                faio_reader(trackp);
                /* NOTREACHED */
        } else {
#ifdef  __needed__
                Uint    t;
#endif

                faio_didwait = FALSE;

                /*
                 * XXX We used to close all track files in the foreground
                 * XXX process. This was not correct before we used "xio"
                 * XXX and with "xio" it will start to fail because we need
                 * XXX the fd handles for the faio_get_buf() function.
                 */
#ifdef  __needed__
                /* close all file-descriptors that only the child will use */
                for (t = 1; t <= trackp->tracks; t++) {
                        if (trackp[t].xfp != NULL)
                                xclose(trackp[t].xfp);
                }
#endif
        }

        return (TRUE);
}

EXPORT BOOL
await_faio()
{
        int     n;
        int     lastfd = -1;
        faio_t  *f;

        /*
         * Wait until the reader is active and has filled the buffer.
         */
        if (lverbose || debug) {
                printf("Waiting for reader process to fill input buffer ... ");
                flush();
        }

        faio_wait_on_buffer(faio_ref(faio_buffers - 1), owner_reader,
                            500*MSECS, 0);

        if (lverbose || debug)
                printf("input buffer ready.\n");

        sp->empty = sp->full = 0L;      /* set correct stat state */
        sp->cont_low = faio_buffers;    /* set cont to max value  */

        f = faio_ref(0);
        for (n = 0; n < faio_buffers; n++, f++) {
                if (f->fd != lastfd &&
                        f->fd == STDIN_FILENO && f->len == 0) {
                        errmsgno(EX_BAD, "Premature EOF on stdin.\n");
                        kill(faio_pid, SIGKILL);
                        return (FALSE);
                }
                lastfd = f->fd;
        }
        return (TRUE);
}

EXPORT void
kill_faio()
{
        if (faio_pid > 0)
                kill(faio_pid, SIGKILL);
}

EXPORT int
wait_faio()
{
        if (faio_pid > 0 && !faio_didwait)
                return (wait(0));
        faio_didwait = TRUE;
        return (0);
}

LOCAL void
faio_reader(trackp)
        track_t *trackp;
{
        /* This function should not return, but _exit. */
        Uint    trackno;

        if (debug)
                printf("\nfaio_reader starting\n");

        for (trackno = 1; trackno <= trackp->tracks; trackno++) {
                if (debug)
                        printf("\nfaio_reader reading track %u\n", trackno);
                faio_read_track(&trackp[trackno]);
        }
        sp->done++;
        if (debug)
                printf("\nfaio_reader all tracks read, exiting\n");

        /* Prevent hang if buffer is larger than all the tracks combined */
        if (sp->gets == 0)
                faio_ref(faio_buffers - 1)->owner = owner_reader;

#ifdef  USE_OS2SHM
        DosFreeMem(buf);
        sleep(30000);   /* XXX If calling _exit() here the parent process seems to be blocked */
                        /* XXX This should be fixed soon */
#endif
        if (debug)
                error("\nfaio_reader _exit(0)\n");
        _exit(0);
}

#ifndef faio_ref
LOCAL faio_t *
faio_ref(n)
        int     n;
{
        return (&((faio_t *)buf)[n]);
}
#endif


LOCAL void
faio_read_track(trackp)
        track_t *trackp;
{
        int     fd = -1;
        int     bytespt = trackp->secsize * trackp->secspt;
        int     secspt = trackp->secspt;
        int     l;
        long    secno = trackp->trackstart;
        tsize_t tracksize = trackp->tracksize;
        tsize_t bytes_read = (tsize_t)0;
        long    bytes_to_read;

        if (trackp->xfp != NULL)
                fd = xfileno(trackp->xfp);

        if (bytespt > faio_buf_size) {
                comerrno(EX_BAD,
                "faio_read_track fatal: secsize %d secspt %d, bytespt(%d) > %d !!\n",
                        trackp->secsize, trackp->secspt, bytespt,
                        faio_buf_size);
        }

        do {
                bytes_to_read = bytespt;
                if (tracksize > 0) {
                        if ((tracksize - bytes_read) > bytespt) {
                                bytes_to_read = bytespt;
                        } else {
                                bytes_to_read = tracksize - bytes_read;
                        }
                }
                l = faio_read_segment(fd, faio_ref(buf_idx_reader), trackp, secno, bytes_to_read);
                if (++buf_idx_reader >= faio_buffers)
                        buf_idx_reader = 0;
                if (l <= 0)
                        break;
                bytes_read += l;
                secno += secspt;
        } while (tracksize < 0 || bytes_read < tracksize);

        xclose(trackp->xfp);    /* Don't keep files open longer than neccesary */
}

LOCAL void
#ifdef  PROTOTYPES
faio_wait_on_buffer(faio_t *f, fowner_t s,
                        unsigned long delay,
                        unsigned long max_wait)
#else
faio_wait_on_buffer(f, s, delay, max_wait)
        faio_t  *f;
        fowner_t s;
        unsigned long delay;
        unsigned long max_wait;
#endif
{
        unsigned long max_loops;

        if (f->owner == s)
                return;         /* return immediately if the buffer is ours */

        if (s == owner_reader)
                sp->empty++;
        else
                sp->full++;

        max_loops = max_wait / delay + 1;

        while (max_wait == 0 || max_loops--) {
                USDEBUG1;
                usleep(delay);
                USDEBUG2;

                if (f->owner == s)
                        return;
        }
        if (debug) {
                errmsgno(EX_BAD,
                "%lu microseconds passed waiting for %d current: %d idx: %ld\n",
                max_wait, s, f->owner, (long)(f - faio_ref(0))/sizeof (*f));
        }
        comerrno(EX_BAD, "faio_wait_on_buffer for %s timed out.\n",
        (s > owner_reader || s < owner_none) ? "bad_owner" : onames[s-owner_none]);
}

LOCAL int
faio_read_segment(fd, f, trackp, secno, len)
        int     fd;
        faio_t  *f;
        track_t *trackp;
        long    secno;
        int     len;
{
        int l;

        faio_wait_on_buffer(f, owner_writer, WRITER_DELAY, WRITER_MAXWAIT);

        f->fd = fd;
        l = fill_buf(fd, trackp, secno, f->bufp, len);
        f->len = l;
        f->saved_errno = geterrno();
        f->owner = owner_reader;
        f->users = sp->users;

        sp->puts++;

        return (l);
}

EXPORT int
faio_read_buf(fd, bp, size)
        int fd;
        char *bp;
        int size;
{
        char *bufp;

        int len = faio_get_buf(fd, &bufp, size);
        if (len > 0) {
                movebytes(bufp, bp, len);
        }
        return (len);
}

EXPORT int
faio_get_buf(fd, bpp, size)
        int fd;
        char **bpp;
        int size;
{
        faio_t  *f;
        int     len;

again:
        f = faio_ref(buf_idx);
        if (f->owner == owner_faio) {
                f->owner = owner_writer;
                if (++buf_idx >= faio_buffers)
                        buf_idx = 0;
                f = faio_ref(buf_idx);
        }

        if ((sp->puts - sp->gets) < sp->cont_low && sp->done == 0) {
                EDEBUG(("gets: %ld puts: %ld cont: %ld low: %ld\n", sp->gets, sp->puts, sp->puts - sp->gets, sp->cont_low));
                sp->cont_low = sp->puts - sp->gets;
        }
        faio_wait_on_buffer(f, owner_reader, READER_DELAY, READER_MAXWAIT);
        len = f->len;

        if (f->fd != fd) {
                if (f->len == 0) {
                        /*
                         * If the tracksize for this track was known, and
                         * the tracksize is 0 mod bytespt, this happens.
                         */
                        goto again;
                }
                comerrno(EX_BAD,
                "faio_get_buf fatal: fd=%d, f->fd=%d, f->len=%d f->errno=%d\n",
                fd, f->fd, f->len, f->saved_errno);
        }
        if (size < len) {
                comerrno(EX_BAD,
                "unexpected short read-attempt in faio_get_buf. size = %d, len = %d\n",
                size, len);
        }

        if (len < 0)
                seterrno(f->saved_errno);

        sp->gets++;

        *bpp = f->bufp;
        if (--f->users <= 0)
                f->owner = owner_faio;
        return (len);
}

EXPORT void
fifo_stats()
{
        if (sp == NULL) /* We might not use a FIFO */
                return;

        errmsgno(EX_BAD, "fifo had %ld puts and %ld gets.\n",
                sp->puts, sp->gets);
        errmsgno(EX_BAD, "fifo was %ld times empty and %ld times full, min fill was %ld%%.\n",
                sp->empty, sp->full, (100L*sp->cont_low)/faio_buffers);
}

EXPORT int
fifo_percent(addone)
        BOOL    addone;
{
        int     percent;

        if (sp == NULL) /* We might not use a FIFO */
                return (-1);

        if (sp->done)
                return (100);
        percent = (100*(sp->puts + 1 - sp->gets)/faio_buffers);
        if (percent > 100)
                return (100);
        return (percent);
}
#else   /* FIFO */

#include <standard.h>
#include <utypes.h>     /* includes sys/types.h */
#include <schily.h>

#include "cdrecord.h"

EXPORT  void    init_fifo       __PR((long));
EXPORT  BOOL    init_faio       __PR((track_t *track, int));
EXPORT  BOOL    await_faio      __PR((void));
EXPORT  void    kill_faio       __PR((void));
EXPORT  int     wait_faio       __PR((void));
EXPORT  int     faio_read_buf   __PR((int f, char *bp, int size));
EXPORT  int     faio_get_buf    __PR((int f, char **bpp, int size));
EXPORT  void    fifo_stats      __PR((void));
EXPORT  int     fifo_percent    __PR((BOOL addone));


EXPORT void
init_fifo(fs)
        long    fs;
{
        errmsgno(EX_BAD, "Fifo not supported.\n");
}

EXPORT BOOL
init_faio(track, bufsize)
        track_t *track;
        int     bufsize;
{
        return (FALSE);
}

EXPORT BOOL
await_faio()
{
        return (TRUE);
}

EXPORT void
kill_faio()
{
}

EXPORT int
wait_faio()
{
        return (0);
}

EXPORT int
faio_read_buf(fd, bp, size)
        int fd;
        char *bp;
        int size;
{
        return (0);
}

EXPORT int
faio_get_buf(fd, bpp, size)
        int fd;
        char **bpp;
        int size;
{
        return (0);
}

EXPORT void
fifo_stats()
{
}

EXPORT int
fifo_percent(addone)
        BOOL    addone;
{
        return (-1);
}

#endif  /* FIFO */