ls.c

这是 gnu 程序中 ls 程序的源代码程序。

/*	$NetBSD: ls.c,v 1.55 2003/12/26 10:51:25 simonb Exp $	*/

/*
 * Copyright (c) 1989, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Michael Fischbein.
 *
 * 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) 1989, 1993, 1994\n\
	The Regents of the University of California.  All rights reserved.\n");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)ls.c	8.7 (Berkeley) 8/5/94";
#else
__RCSID("$NetBSD: ls.c,v 1.55 2003/12/26 10:51:25 simonb Exp $");
#endif
#endif /* not lint */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>

#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fts.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <termios.h>
#include <pwd.h>
#include <grp.h>

#include "ls.h"
#include "extern.h"

static void	 display(FTSENT *, FTSENT *);
static int	 mastercmp(const FTSENT **, const FTSENT **);
static void	 traverse(int, char **, int);

static void (*printfcn)(DISPLAY *);
static int (*sortfcn)(const FTSENT *, const FTSENT *);

#define	BY_NAME 0
#define	BY_SIZE 1
#define	BY_TIME	2

long blocksize;			/* block size units */
int termwidth = 80;		/* default terminal width */
int sortkey = BY_NAME;
int rval = EXIT_SUCCESS;	/* exit value - set if error encountered */

/* flags */
int f_accesstime;		/* use time of last access */
int f_column;			/* columnated format */
int f_columnacross;		/* columnated format, sorted across */
int f_flags;			/* show flags associated with a file */
int f_grouponly;		/* long listing without owner */
int f_humanize;			/* humanize the size field */
int f_inode;			/* print inode */
int f_listdir;			/* list actual directory, not contents */
int f_listdot;			/* list files beginning with . */
int f_longform;			/* long listing format */
int f_nonprint;			/* show unprintables as ? */
int f_nosort;			/* don't sort output */
int f_numericonly;		/* don't convert uid/gid to name */
int f_octal;			/* print octal escapes for nongraphic characters */
int f_octal_escape;		/* like f_octal but use C escapes if possible */
int f_recursive;		/* ls subdirectories also */
int f_reversesort;		/* reverse whatever sort is used */
int f_sectime;			/* print the real time for all files */
int f_singlecol;		/* use single column output */
int f_size;			/* list size in short listing */
int f_statustime;		/* use time of last mode change */
int f_stream;			/* stream format */
int f_type;			/* add type character for non-regular files */
int f_typedir;			/* add type character for directories */
int f_whiteout;			/* show whiteout entries */

int
ls_main(int argc, char *argv[])
{
	static char dot[] = ".", *dotav[] = { dot, NULL };
	struct winsize win;
	int ch, fts_options;
	int kflag = 0;
	const char *p;

	setlocale(LC_ALL, "");

	/* Terminal defaults to -Cq, non-terminal defaults to -1. */
	if (isatty(STDOUT_FILENO)) {
		if ((p = getenv("COLUMNS")) != NULL)
			termwidth = atoi(p);
		else if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) == 0 &&
		    win.ws_col > 0)
			termwidth = win.ws_col;
		f_column = f_nonprint = 1;
	} else
		f_singlecol = 1;

	/* Root is -A automatically. */
	if (!getuid())
		f_listdot = 1;

	fts_options = FTS_PHYSICAL;
	while ((ch = getopt(argc, argv, "1ABCFLRSTWabcdfghiklmnopqrstuwx")) != -1) {
		switch (ch) {
		/*
		 * The -1, -C, -l, -m and -x options all override each other so
		 * shell aliasing works correctly.
		 */
		case '1':
			f_singlecol = 1;
			f_column = f_columnacross = f_longform = f_stream = 0;
			break;
		case 'C':
			f_column = 1;
			f_columnacross = f_longform = f_singlecol = f_stream =
			    0;
			break;
		case 'g':
			if (f_grouponly != -1)
				f_grouponly = 1;
			f_longform = 1;
			f_column = f_columnacross = f_singlecol = f_stream = 0;
			break;
		case 'l':
			f_longform = 1;
			f_column = f_columnacross = f_singlecol = f_stream = 0;
			/* Never let -g take precedence over -l. */
			f_grouponly = -1;
			break;
		case 'm':
			f_stream = 1;
			f_column = f_columnacross = f_longform = f_singlecol =
			    0;
			break;
		case 'x':
			f_columnacross = 1;
			f_column = f_longform = f_singlecol = f_stream = 0;
			break;
		/* The -c and -u options override each other. */
		case 'c':
			f_statustime = 1;
			f_accesstime = 0;
			break;
		case 'u':
			f_accesstime = 1;
			f_statustime = 0;
			break;
		case 'F':
			f_type = 1;
			break;
		case 'L':
			fts_options &= ~FTS_PHYSICAL;
			fts_options |= FTS_LOGICAL;
			break;
		case 'R':
			f_recursive = 1;
			break;
		case 'a':
			fts_options |= FTS_SEEDOT;
			/* FALLTHROUGH */
		case 'A':
			f_listdot = 1;
			break;
		/* the -B option turns off the -b, -q and -w options. */
		case 'B':
			f_nonprint = 0;
			f_octal = 1;
			f_octal_escape = 0;
			break;
		/* the -b option turns off the -B, -q and -w options. */
		case 'b':
			f_nonprint = 0;
			f_octal = 0;
			f_octal_escape = 1;
			break;
		/* The -d option turns off the -R option. */
		case 'd':
			f_listdir = 1;
			f_recursive = 0;
			break;
		case 'f':
			f_nosort = 1;
			break;
		case 'i':
			f_inode = 1;
			break;
		case 'k':
			blocksize = 1024;
			kflag = 1;
			break;
		/*
		 * The -h option forces all sizes to be measured in bytes.
		 * It also makes -l suppress -s.
		 */
		case 'h':
			f_humanize = 1;
			break;
		case 'n':
			f_numericonly = 1;
			break;
		case 'o':
			f_flags = 1;
			break;
		case 'p':
			f_typedir = 1;
			break;
		/* the -q option turns off the -B, -b and -w options. */
		case 'q':
			f_nonprint = 1;
			f_octal = 0;
			f_octal_escape = 0;
			break;
		case 'r':
			f_reversesort = 1;
			break;
		case 'S':
			sortkey = BY_SIZE;
			break;
		case 's':
			f_size = 1;
			break;
		case 'T':
			f_sectime = 1;
			break;
		case 't':
			sortkey = BY_TIME;
			break;
		case 'W':
			f_whiteout = 1;
			break;
		/* the -w option turns off the -B, -b and -q options. */
		case 'w':
			f_nonprint = 0;
			f_octal = 0;
			f_octal_escape = 0;
			break;
		default:
		case '?':
			usage();
		}
	}
	argc -= optind;
	argv += optind;

	/*
	 * If both -g and -l options, let -l take precedence.
	 */
	if (f_grouponly == -1)
		f_grouponly = 0;

	/*
	 * If not -F, -i, -l, -p, -S, -s or -t options, don't require stat
	 * information.
	 */
	if (!f_inode && !f_longform && !f_size && !f_type && !f_typedir &&
	    sortkey == BY_NAME)
		fts_options |= FTS_NOSTAT;

	/*
	 * If not -F, -d or -l options, follow any symbolic links listed on
	 * the command line.
	 */
	if (!f_longform && !f_listdir && !f_type)
		fts_options |= FTS_COMFOLLOW;

	/*
	 * If -W, show whiteout entries
	 */
#ifdef FTS_WHITEOUT
	if (f_whiteout)
		fts_options |= FTS_WHITEOUT;
#endif

	/* If -l or -s, figure out block size. */
	if (f_inode || f_longform || f_size) {
		if (!kflag)
			(void)getbsize(NULL, &blocksize);
		blocksize /= 512;
	}

	/* Select a sort function. */
	if (f_reversesort) {
		switch (sortkey) {
		case BY_NAME:
			sortfcn = revnamecmp;
			break;
		case BY_SIZE:
			sortfcn = revsizecmp;
			break;
		case BY_TIME:
			if (f_accesstime)
				sortfcn = revacccmp;
			else if (f_statustime)
				sortfcn = revstatcmp;
			else /* Use modification time. */
				sortfcn = revmodcmp;
			break;
		}