306 lines
7.3 KiB
C
306 lines
7.3 KiB
C
|
/*-
|
||
|
|
* Copyright (c) 1991, 1993
|
||
|
|
* The Regents of the University of California. All rights reserved.
|
||
|
|
*
|
||
|
|
* This code is derived from software contributed to Berkeley by
|
||
|
|
* Edward Sze-Tyan Wang.
|
||
|
|
*
|
||
|
|
* 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.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <sys/cdefs.h>
|
||
|
|
#ifndef lint
|
||
|
|
__COPYRIGHT("@(#) Copyright (c) 1991, 1993\
|
||
|
|
The Regents of the University of California. All rights reserved.");
|
||
|
|
#endif /* not lint */
|
||
|
|
|
||
|
|
#ifndef lint
|
||
|
|
#if 0
|
||
|
|
static char sccsid[] = "@(#)tail.c 8.1 (Berkeley) 6/6/93";
|
||
|
|
#endif
|
||
|
|
__RCSID("$NetBSD: tail.c,v 1.17 2013/01/31 23:09:06 wiz Exp $");
|
||
|
|
#endif /* not lint */
|
||
|
|
|
||
|
|
#include <sys/types.h>
|
||
|
|
#include <sys/stat.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#include <unistd.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include "extern.h"
|
||
|
|
|
||
|
|
int fflag, rflag, rval;
|
||
|
|
const char *fname;
|
||
|
|
|
||
|
|
static void obsolete(char **);
|
||
|
|
static void usage(void) __dead;
|
||
|
|
|
||
|
|
int
|
||
|
|
main(int argc, char *argv[])
|
||
|
|
{
|
||
|
|
struct stat sb;
|
||
|
|
FILE *fp;
|
||
|
|
off_t off;
|
||
|
|
enum STYLE style;
|
||
|
|
int ch, first;
|
||
|
|
char *p;
|
||
|
|
|
||
|
|
setprogname(argv[0]);
|
||
|
|
off = 0;
|
||
|
|
/*
|
||
|
|
* Tail's options are weird. First, -n10 is the same as -n-10, not
|
||
|
|
* -n+10. Second, the number options are 1 based and not offsets,
|
||
|
|
* so -n+1 is the first line, and -c-1 is the last byte. Third, the
|
||
|
|
* number options for the -r option specify the number of things that
|
||
|
|
* get displayed, not the starting point in the file. The one major
|
||
|
|
* incompatibility in this version as compared to historical versions
|
||
|
|
* is that the 'r' option couldn't be modified by the -lbc options,
|
||
|
|
* i.e., it was always done in lines. This version treats -rc as a
|
||
|
|
* number of characters in reverse order. Finally, the default for
|
||
|
|
* -r is the entire file, not 10 lines.
|
||
|
|
*/
|
||
|
|
#define ARG(units, forward, backward) { \
|
||
|
|
if (style) \
|
||
|
|
usage(); \
|
||
|
|
off = strtoll(optarg, &p, 10) * (units); \
|
||
|
|
if (*p) \
|
||
|
|
xerrx(1, "illegal offset -- %s", optarg); \
|
||
|
|
switch(optarg[0]) { \
|
||
|
|
case '+': \
|
||
|
|
if (off) \
|
||
|
|
off -= (units); \
|
||
|
|
style = (forward); \
|
||
|
|
break; \
|
||
|
|
case '-': \
|
||
|
|
off = -off; \
|
||
|
|
/* FALLTHROUGH */ \
|
||
|
|
default: \
|
||
|
|
style = (backward); \
|
||
|
|
break; \
|
||
|
|
} \
|
||
|
|
}
|
||
|
|
|
||
|
|
obsolete(argv);
|
||
|
|
style = NOTSET;
|
||
|
|
while ((ch = getopt(argc, argv, "Fb:c:fn:r")) != -1)
|
||
|
|
switch(ch) {
|
||
|
|
case 'F':
|
||
|
|
fflag = 2;
|
||
|
|
break;
|
||
|
|
case 'b':
|
||
|
|
ARG(512, FBYTES, RBYTES);
|
||
|
|
break;
|
||
|
|
case 'c':
|
||
|
|
ARG(1, FBYTES, RBYTES);
|
||
|
|
break;
|
||
|
|
case 'f':
|
||
|
|
fflag = 1;
|
||
|
|
break;
|
||
|
|
case 'n':
|
||
|
|
ARG(1, FLINES, RLINES);
|
||
|
|
break;
|
||
|
|
case 'r':
|
||
|
|
rflag = 1;
|
||
|
|
break;
|
||
|
|
case '?':
|
||
|
|
default:
|
||
|
|
usage();
|
||
|
|
}
|
||
|
|
argc -= optind;
|
||
|
|
argv += optind;
|
||
|
|
|
||
|
|
if (fflag && argc > 1)
|
||
|
|
xerrx(1,
|
||
|
|
"-f and -F options only appropriate for a single file");
|
||
|
|
|
||
|
|
/*
|
||
|
|
* If displaying in reverse, don't permit follow option, and convert
|
||
|
|
* style values.
|
||
|
|
*/
|
||
|
|
if (rflag) {
|
||
|
|
if (fflag)
|
||
|
|
usage();
|
||
|
|
if (style == FBYTES)
|
||
|
|
style = RBYTES;
|
||
|
|
else if (style == FLINES)
|
||
|
|
style = RLINES;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* If style not specified, the default is the whole file for -r, and
|
||
|
|
* the last 10 lines if not -r.
|
||
|
|
*/
|
||
|
|
if (style == NOTSET) {
|
||
|
|
if (rflag) {
|
||
|
|
off = 0;
|
||
|
|
style = REVERSE;
|
||
|
|
} else {
|
||
|
|
off = 10;
|
||
|
|
style = RLINES;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (*argv)
|
||
|
|
for (first = 1; (fname = *argv++) != NULL;) {
|
||
|
|
if ((fp = fopen(fname, "r")) == NULL ||
|
||
|
|
fstat(fileno(fp), &sb)) {
|
||
|
|
ierr();
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
if (argc > 1) {
|
||
|
|
(void)printf("%s==> %s <==\n",
|
||
|
|
first ? "" : "\n", fname);
|
||
|
|
first = 0;
|
||
|
|
(void)fflush(stdout);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (rflag)
|
||
|
|
reverse(fp, style, off, &sb);
|
||
|
|
else
|
||
|
|
forward(fp, style, off, &sb);
|
||
|
|
(void)fclose(fp);
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
fname = "stdin";
|
||
|
|
|
||
|
|
if (fstat(fileno(stdin), &sb)) {
|
||
|
|
ierr();
|
||
|
|
exit(1);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Determine if input is a pipe. 4.4BSD will set the SOCKET
|
||
|
|
* bit in the st_mode field for pipes. Fix this then.
|
||
|
|
*/
|
||
|
|
if (lseek(fileno(stdin), (off_t)0, SEEK_CUR) == -1 &&
|
||
|
|
errno == ESPIPE) {
|
||
|
|
errno = 0;
|
||
|
|
fflag = 0; /* POSIX.2 requires this. */
|
||
|
|
}
|
||
|
|
|
||
|
|
if (rflag)
|
||
|
|
reverse(stdin, style, off, &sb);
|
||
|
|
else
|
||
|
|
forward(stdin, style, off, &sb);
|
||
|
|
}
|
||
|
|
exit(rval);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Convert the obsolete argument form into something that getopt can handle.
|
||
|
|
* This means that anything of the form [+-][0-9][0-9]*[lbc][fr] that isn't
|
||
|
|
* the option argument for a -b, -c or -n option gets converted.
|
||
|
|
*/
|
||
|
|
static void
|
||
|
|
obsolete(char *argv[])
|
||
|
|
{
|
||
|
|
char *ap, *p, *t;
|
||
|
|
int len;
|
||
|
|
char *start;
|
||
|
|
|
||
|
|
while ((ap = *++argv) != NULL) {
|
||
|
|
/* Return if "--" or not an option of any form. */
|
||
|
|
if (ap[0] != '-') {
|
||
|
|
if (ap[0] != '+')
|
||
|
|
return;
|
||
|
|
} else if (ap[1] == '-')
|
||
|
|
return;
|
||
|
|
|
||
|
|
switch (*++ap) {
|
||
|
|
/* Old-style option. */
|
||
|
|
case '0': case '1': case '2': case '3': case '4':
|
||
|
|
case '5': case '6': case '7': case '8': case '9':
|
||
|
|
|
||
|
|
/* Malloc space for dash, new option and argument. */
|
||
|
|
len = strlen(*argv);
|
||
|
|
if ((start = p = malloc(len + 3)) == NULL)
|
||
|
|
xerr(1, "malloc");
|
||
|
|
*p++ = '-';
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Go to the end of the option argument. Save off any
|
||
|
|
* trailing options (-3lf) and translate any trailing
|
||
|
|
* output style characters.
|
||
|
|
*/
|
||
|
|
t = *argv + len - 1;
|
||
|
|
if (*t == 'f' || *t == 'r') {
|
||
|
|
*p++ = *t;
|
||
|
|
*t-- = '\0';
|
||
|
|
}
|
||
|
|
switch(*t) {
|
||
|
|
case 'b':
|
||
|
|
*p++ = 'b';
|
||
|
|
*t = '\0';
|
||
|
|
break;
|
||
|
|
case 'c':
|
||
|
|
*p++ = 'c';
|
||
|
|
*t = '\0';
|
||
|
|
break;
|
||
|
|
case 'l':
|
||
|
|
*t = '\0';
|
||
|
|
/* FALLTHROUGH */
|
||
|
|
case '0': case '1': case '2': case '3': case '4':
|
||
|
|
case '5': case '6': case '7': case '8': case '9':
|
||
|
|
*p++ = 'n';
|
||
|
|
break;
|
||
|
|
default:
|
||
|
|
xerrx(1, "illegal option -- %s", *argv);
|
||
|
|
}
|
||
|
|
*p++ = *argv[0];
|
||
|
|
(void)strcpy(p, ap);
|
||
|
|
*argv = start;
|
||
|
|
continue;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Options w/ arguments, skip the argument and continue
|
||
|
|
* with the next option.
|
||
|
|
*/
|
||
|
|
case 'b':
|
||
|
|
case 'c':
|
||
|
|
case 'n':
|
||
|
|
if (!ap[1])
|
||
|
|
++argv;
|
||
|
|
/* FALLTHROUGH */
|
||
|
|
/* Options w/o arguments, continue with the next option. */
|
||
|
|
case 'f':
|
||
|
|
case 'r':
|
||
|
|
continue;
|
||
|
|
|
||
|
|
/* Illegal option, return and let getopt handle it. */
|
||
|
|
default:
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static void
|
||
|
|
usage(void)
|
||
|
|
{
|
||
|
|
(void)fprintf(stderr,
|
||
|
|
"Usage: %s [-f | -F | -r] [-b # | -c # | -n #] [file ...]\n",
|
||
|
|
getprogname());
|
||
|
|
exit(1);
|
||
|
|
}
|