cmd/tail/forward.c

	forward.c revision 209e49b2ff611e7d61ff58e13756ae67f51be550
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love/*
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * Copyright (c) 1991, 1993
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *  The Regents of the University of California.  All rights reserved.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * This code is derived from software contributed to Berkeley by
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * Edward Sze-Tyan Wang.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * Redistribution and use in source and binary forms, with or without
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * modification, are permitted provided that the following conditions
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * are met:
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * 1. Redistributions of source code must retain the above copyright
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *    notice, this list of conditions and the following disclaimer.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * 2. Redistributions in binary form must reproduce the above copyright
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *    notice, this list of conditions and the following disclaimer in the
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *    documentation and/or other materials provided with the distribution.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * 4. Neither the name of the University nor the names of its contributors
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *    may be used to endorse or promote products derived from this software
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *    without specific prior written permission.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * SUCH DAMAGE.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love/*
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * Solaris porting notes:  the original FreeBSD version made use of the
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *                         BSD kqueue event notification framework; this
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *                         was changed to use the Solaris event completion
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *                         framework: port_create(), port_associate(),
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *                         and port_get().
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <sys/param.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <sys/mount.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <sys/types.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <sys/stat.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <sys/statfs.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <sys/statvfs.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <sys/time.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <sys/mman.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <sys/poll.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <port.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <err.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <errno.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <fcntl.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <limits.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <stdio.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <stdlib.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <string.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include <unistd.h>
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#include "extern.h"
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovestatic void rlines(FILE *, const char *fn, off_t, struct stat *);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovestatic int show(file_info_t *);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovestatic void set_events(file_info_t *files);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love/* defines for inner loop actions */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#define USE_SLEEP   0
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#define USE_PORT    1
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love#define ADD_EVENTS  2
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Loveint port;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Loveint action = USE_SLEEP;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Loveport_event_t ev;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovestatic const file_info_t *last;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love/*
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * forward -- display the file, from an offset, forward.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * There are eight separate cases for this -- regular and non-regular
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * files, by bytes or lines and from the beginning or end of the file.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * FBYTES   byte offset from the beginning of the file
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *  REG seek
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *  NOREG   read, counting bytes
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * FLINES   line offset from the beginning of the file
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *  REG read, counting lines
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *  NOREG   read, counting lines
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * RBYTES   byte offset from the end of the file
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *  REG seek
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *  NOREG   cyclically read characters into a wrap-around buffer
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * RLINES
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *  REG mmap the file and step back until reach the correct offset.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *  NOREG   cyclically read lines into a wrap-around array of buffers
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovevoid
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Loveforward(FILE *fp, const char *fn, enum STYLE style, off_t off, struct stat *sbp)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love{
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    int ch;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    switch (style) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    case FBYTES:
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (off == 0)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (S_ISREG(sbp->st_mode)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (sbp->st_size < off)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                off = sbp->st_size;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (fseeko(fp, off, SEEK_SET) == -1) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        } else while (off--)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if ((ch = getc(fp)) == EOF) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                if (ferror(fp)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    case FLINES:
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (off == 0)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        for (;;) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if ((ch = getc(fp)) == EOF) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                if (ferror(fp)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (ch == '\n' && !--off)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    case RBYTES:
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (S_ISREG(sbp->st_mode)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (sbp->st_size >= off &&
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                fseeko(fp, -off, SEEK_END) == -1) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        } else if (off == 0) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            while (getc(fp) != EOF)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                ;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (ferror(fp)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        } else
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (bytes(fp, fn, off))
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    case RLINES:
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (S_ISREG(sbp->st_mode))
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (!off) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                if (fseeko(fp, (off_t)0, SEEK_END) == -1) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            } else
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                rlines(fp, fn, off, sbp);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        else if (off == 0) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            while (getc(fp) != EOF)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                ;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (ferror(fp)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        } else
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (lines(fp, fn, off))
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    default:
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    while ((ch = getc(fp)) != EOF)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (putchar(ch) == EOF)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            oerr();
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    if (ferror(fp)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    (void) fflush(stdout);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love}
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love/*
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * rlines -- display the last offset lines of the file.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovestatic void
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Loverlines(FILE *fp, const char *fn, off_t off, struct stat *sbp)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love{
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    struct mapinfo map;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    off_t curoff, size;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    int i;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    if ((size = sbp->st_size) == 0)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    map.start = NULL;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    map.fd = fileno(fp);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    map.mapoff = map.maxoff = size;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    /*
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love     * Last char is special, ignore whether newline or not. Note that
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love     * size == 0 is dealt with above, and size == 1 sets curoff to -1.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love     */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    curoff = size - 2;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    while (curoff >= 0) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (curoff < map.mapoff && maparound(&map, curoff) != 0) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        for (i = curoff - map.mapoff; i >= 0; i--)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (map.start[i] == '\n' && --off == 0)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        /* `i' is either the map offset of a '\n', or -1. */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        curoff = map.mapoff + i;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (i >= 0)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    curoff++;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    if (mapprint(&map, curoff, size - curoff) != 0) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        exit(1);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    /* Set the file pointer to reflect the length displayed. */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    if (fseeko(fp, sbp->st_size, SEEK_SET) == -1) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    if (map.start != NULL && munmap(map.start, map.maplen)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        ierr(fn);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love}
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovestatic int
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Loveshow(file_info_t *file)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love{
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    int ch;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    while ((ch = getc(file->fp)) != EOF) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (last != file && no_files > 1) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (!qflag)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                (void) printf("\n==> %s <==\n",
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    file->file_name);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            last = file;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (putchar(ch) == EOF)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            oerr();
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    (void) fflush(stdout);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    if (ferror(file->fp)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        (void) fclose(file->fp);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        file->fp = NULL;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        ierr(file->file_name);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        return (0);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    clearerr(file->fp);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    return (1);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love}
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovestatic void
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Loveset_events(file_info_t *files)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love{
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    int i;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    file_info_t *file;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    action = USE_PORT;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    for (i = 0, file = files; i < no_files; i++, file++) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (! file->fp)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            continue;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        (void) fstat(fileno(file->fp), &file->st);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        /* For -f or -F will both use Solaris port interface */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (fflag && (fileno(file->fp) != STDIN_FILENO)) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            (void) port_associate(port, PORT_SOURCE_FD,
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                fileno(file->fp), POLLIN, (void*)file);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love}
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love/*
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love * follow -- display the file, from an offset, forward.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love *
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovevoid
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Lovefollow(file_info_t *files, enum STYLE style, off_t off)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love{
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    int active, ev_change, i, n = -1;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    struct stat sb2;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    file_info_t *file;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    struct timespec ts;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    /* Position each of the files */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    file = files;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    active = 0;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    n = 0;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    for (i = 0; i < no_files; i++, file++) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (file->fp) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            active = 1;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            n++;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (no_files > 1 && !qflag)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                (void) printf("\n==> %s <==\n",
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    file->file_name);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            forward(file->fp, file->file_name, style, off,
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                &file->st);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (Fflag && fileno(file->fp) != STDIN_FILENO)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                n++;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    if (!Fflag && !active)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        return;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    last = --file;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    port = port_create();
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    set_events(files);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    for (;;) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        ev_change = 0;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (Fflag) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            for (i = 0, file = files; i < no_files; i++, file++) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                if (!file->fp) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    file->fp = fopen(file->file_name, "r");
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    if (file->fp != NULL &&
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                        fstat(fileno(file->fp), &file->st)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                        == -1) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                        (void) fclose(file->fp);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                        file->fp = NULL;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    if (file->fp != NULL)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                        ev_change++;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    continue;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                if (fileno(file->fp) == STDIN_FILENO)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    continue;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                if (stat(file->file_name, &sb2) == -1) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    if (errno != ENOENT)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                        ierr(file->file_name);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    (void) show(file);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    (void) fclose(file->fp);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    file->fp = NULL;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    ev_change++;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    continue;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                if (sb2.st_ino != file->st.st_ino ||
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    sb2.st_dev != file->st.st_dev ||
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    sb2.st_nlink == 0) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    (void) show(file);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    file->fp = freopen(file->file_name, "r",
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                        file->fp);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    if (file->fp != NULL)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                        (void) memcpy(&file->st, &sb2,
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                            sizeof (struct stat));
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    else if (errno != ENOENT)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                        ierr(file->file_name);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    ev_change++;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        for (i = 0, file = files; i < no_files; i++, file++)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (file->fp && !show(file))
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                ev_change++;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        if (ev_change)
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            set_events(files);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        switch (action) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        case USE_PORT:
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            ts.tv_sec = 1;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            ts.tv_nsec = 0;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            /*
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love             * In the -F case we set a timeout to ensure that
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love             * we re-stat the file at least once every second.
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love             */
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            n = port_get(port, &ev, Fflag? &ts : NULL);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            if (n == 0) {
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                file = (file_info_t *)ev.portev_user;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                (void) port_associate(port, PORT_SOURCE_FD,
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love                    fileno(file->fp), POLLIN, (void*)file);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        case USE_SLEEP:
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            (void) usleep(250000);
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love            break;
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love        }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love    }
209e49b2ff611e7d61ff58e13756ae67f51be550Chris Love}