Initial revision
diff --git a/ls.c b/ls.c
new file mode 100644
index 0000000..2566bee
--- /dev/null
+++ b/ls.c
@@ -0,0 +1,542 @@
+#include "internal.h"
+/*
+ * tiny-ls.c version 0.1.0: A minimalist 'ls'
+ * Copyright (C) 1996 Brian Candler <B.Candler@pobox.com>
+ * 
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  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; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/*
+ * To achieve a small memory footprint, this version of 'ls' doesn't do any
+ * file sorting, and only has the most essential command line switches
+ * (i.e. the ones I couldn't live without :-) All features which involve
+ * linking in substantial chunks of libc can be disabled.
+ *
+ * Although I don't really want to add new features to this program to
+ * keep it small, I *am* interested to receive bug fixes and ways to make
+ * it more portable.
+ *
+ * KNOWN BUGS:
+ * 1. messy output if you mix files and directories on the command line
+ * 2. ls -l of a directory doesn't give "total <blocks>" header
+ * 3. ls of a symlink to a directory doesn't list directory contents
+ * 4. hidden files can make column width too large
+ * NON-OPTIMAL BEHAVIOUR:
+ * 1. autowidth reads directories twice
+ * 2. if you do a short directory listing without filetype characters
+ *    appended, there's no need to stat each one
+ * PORTABILITY:
+ * 1. requires lstat (BSD) - how do you do it without?
+ */
+
+#define FEATURE_USERNAME	/* show username/groupnames (libc6 uses NSS) */
+#define FEATURE_TIMESTAMPS	/* show file timestamps */
+#define FEATURE_AUTOWIDTH	/* calculate terminal & column widths */
+#define FEATURE_FILETYPECHAR	/* enable -p and -F */
+
+#undef	OP_BUF_SIZE	1024	/* leave undefined for unbuffered output */
+
+#define TERMINAL_WIDTH	80	/* use 79 if your terminal has linefold bug */
+#define	COLUMN_WIDTH	14	/* default if AUTOWIDTH not defined */
+#define COLUMN_GAP	2	/* includes the file type char, if present */
+
+/************************************************************************/
+
+#define HAS_REWINDDIR
+
+#if 1 /* FIXME libc 6 */
+# include <linux/types.h> 
+#else
+# include <sys/types.h> 
+#endif
+#include <sys/stat.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <errno.h>
+#include <stdio.h>
+#ifdef FEATURE_USERNAME
+#include <pwd.h>
+#include <grp.h>
+#endif
+#ifdef FEATURE_TIMESTAMPS
+#include <time.h>
+#endif
+
+#define TYPEINDEX(mode)	(((mode) >> 12) & 0x0f)
+#define TYPECHAR(mode)	("0pcCd?bB-?l?s???" [TYPEINDEX(mode)])
+#ifdef FEATURE_FILETYPECHAR
+#define APPCHAR(mode)	("\0|\0\0/\0\0\0\0\0@\0=\0\0\0" [TYPEINDEX(mode)])
+#endif
+
+#ifndef MAJOR
+#define MAJOR(dev) (((dev)>>8)&0xff)
+#define MINOR(dev) ((dev)&0xff)
+#endif
+
+#define MODE1  "rwxrwxrwx"
+#define MODE0  "---------"
+#define SMODE1 "..s..s..t"
+#define SMODE0 "..S..S..T"
+
+/* The 9 mode bits to test */
+
+static const umode_t MBIT[] = {
+  S_IRUSR, S_IWUSR, S_IXUSR,
+  S_IRGRP, S_IWGRP, S_IXGRP,
+  S_IROTH, S_IWOTH, S_IXOTH
+};
+
+/* The special bits. If set, display SMODE0/1 instead of MODE0/1 */
+
+static const umode_t SBIT[] = {
+  0, 0, S_ISUID,
+  0, 0, S_ISGID,
+  0, 0, S_ISVTX
+};
+
+#define FMT_AUTO	0
+#define FMT_LONG	1	/* one record per line, extended info */
+#define FMT_SINGLE	2	/* one record per line */
+#define FMT_ROWS	3	/* print across rows */
+#define FMT_COLUMNS	3	/* fill columns (same, since we don't sort) */
+
+#define TIME_MOD	0
+#define TIME_CHANGE	1
+#define TIME_ACCESS	2
+
+#define DISP_FTYPE	1	/* show character for file type */
+#define DISP_EXEC	2	/* show '*' if regular executable file */
+#define DISP_HIDDEN	4	/* show files starting . (except . and ..) */
+#define DISP_DOT	8	/* show . and .. */
+#define DISP_NUMERIC	16	/* numeric uid and gid */
+#define DISP_FULLTIME	32	/* show extended time display */
+#define DIR_NOLIST	64	/* show directory as itself, not contents */
+#define DISP_DIRNAME	128	/* show directory name (for internal use) */
+#define DIR_RECURSE	256	/* -R (not yet implemented) */
+
+static unsigned char	display_fmt = FMT_AUTO;
+static unsigned short	opts = 0;
+static unsigned short	column = 0;
+
+#ifdef FEATURE_AUTOWIDTH
+static unsigned short terminal_width = 0, column_width = 0;
+#else
+#define terminal_width	TERMINAL_WIDTH
+#define column_width	COLUMN_WIDTH
+#endif
+
+#ifdef FEATURE_TIMESTAMPS
+static unsigned char time_fmt = TIME_MOD;
+#endif
+
+#define wr(data,len) fwrite(data, 1, len, stdout)
+
+static void writenum(long val, short minwidth)
+{
+	char	scratch[20];
+
+	char *p = scratch + sizeof(scratch);
+	short len = 0;
+	short neg = (val < 0);
+	
+	if (neg) val = -val;
+	do
+		*--p = (val % 10) + '0', len++, val /= 10;
+	while (val);
+	if (neg)
+		*--p = '-', len++;
+	while (len < minwidth)
+		*--p = ' ', len++;
+	wr(p, len);
+	column += len;
+}
+
+static void newline(void)
+{
+	if (column > 0) {
+		wr("\n", 1);
+		column = 0;
+	}
+}
+
+static void tab(short col)
+{
+	static const char spaces[] = "                ";
+	#define nspaces ((sizeof spaces)-1)	/* null terminator! */
+	
+	short n = col - column;
+
+	if (n > 0) {
+		column = col;
+		while (n > nspaces) {
+			wr(spaces, nspaces);
+			n -= nspaces;
+		}
+		/* must be 1...(sizeof spaces) left */
+		wr(spaces, n);
+	}
+	#undef nspaces
+}
+
+#ifdef FEATURE_FILETYPECHAR
+static char append_char(umode_t mode)
+{
+	if (!(opts & DISP_FTYPE))
+		return '\0';
+	if ((opts & DISP_EXEC) && S_ISREG(mode) && (mode & (S_IXUSR|S_IXGRP|S_IXOTH)))
+		return '*';
+	return APPCHAR(mode);
+}
+#endif
+
+/**
+ **
+ ** Display a file or directory as a single item
+ ** (in either long or short format)
+ **
+ **/
+
+static void list_single(const char *name, struct stat *info)
+{
+	char scratch[20];
+	short len = strlen(name);
+#ifdef FEATURE_FILETYPECHAR
+	char append = append_char(info->st_mode);
+#endif
+	
+	if (display_fmt == FMT_LONG) {
+		umode_t mode = info->st_mode; 
+		int i;
+		
+		scratch[0] = TYPECHAR(mode);
+		for (i=0; i<9; i++)
+			if (mode & SBIT[i])
+				scratch[i+1] = (mode & MBIT[i])
+						? SMODE1[i]
+						: SMODE0[i];
+			else
+				scratch[i+1] = (mode & MBIT[i])
+						? MODE1[i]
+						: MODE0[i];
+		newline();
+		wr(scratch, 10);
+		column=10;
+		writenum((long)info->st_nlink,(short)4);
+		fputs(" ", stdout);
+#ifdef FEATURE_USERNAME
+		if (!(opts & DISP_NUMERIC)) {
+			struct passwd *pw = getpwuid(info->st_uid);
+			if (pw)
+				fputs(pw->pw_name, stdout);
+			else
+				writenum((long)info->st_uid,(short)0);
+		} else
+#endif
+		writenum((long)info->st_uid,(short)0);
+		tab(24);
+#ifdef FEATURE_USERNAME
+		if (!(opts & DISP_NUMERIC)) {
+			struct group *gr = getgrgid(info->st_gid);
+			if (gr)
+				fputs(gr->gr_name, stdout);
+			else
+				writenum((long)info->st_gid,(short)0);
+		} else
+#endif
+		writenum((long)info->st_gid,(short)0);
+		tab(33);
+		if (S_ISBLK(mode) || S_ISCHR(mode)) {
+			writenum((long)MAJOR(info->st_rdev),(short)3);
+			fputs(", ", stdout);
+			writenum((long)MINOR(info->st_rdev),(short)3);
+		}
+		else
+			writenum((long)info->st_size,(short)8);
+		fputs(" ", stdout);
+#ifdef FEATURE_TIMESTAMPS
+		{
+			time_t cal;
+			char *string;
+			
+			switch(time_fmt) {
+			case TIME_CHANGE:
+				cal=info->st_ctime; break;
+			case TIME_ACCESS:
+				cal=info->st_atime; break;
+			default:
+				cal=info->st_mtime; break;
+			}
+			string=ctime(&cal);
+			if (opts & DISP_FULLTIME)
+				wr(string,24);
+			else {
+				time_t age = time(NULL) - cal;
+				wr(string+4,7);	/* mmm_dd_ */
+				if(age < 3600L*24*365/2 && age > -15*60)
+					/* hh:mm if less than 6 months old */
+					wr(string+11,5);
+				else
+					/* _yyyy otherwise */
+					wr(string+19,5);
+			}
+			wr(" ", 1);
+		}
+#else
+		fputs("--- -- ----- ", stdout);
+#endif
+		wr(name, len);
+		if (S_ISLNK(mode)) {
+			wr(" -> ", 4);
+			len = readlink(name, scratch, sizeof scratch);
+			if (len > 0) fwrite(scratch, 1, len, stdout);
+#ifdef FEATURE_FILETYPECHAR
+			/* show type of destination */
+			if (opts & DISP_FTYPE) {
+				if (!stat(name, info)) {
+					append = append_char(info->st_mode);
+					if (append)
+						fputc(append, stdout);
+				}
+			}
+#endif
+		}
+#ifdef FEATURE_FILETYPECHAR
+		else if (append)
+			wr(&append, 1);
+#endif
+	} else {
+		static short nexttab = 0;
+		
+		/* sort out column alignment */
+		if (column == 0)
+			; /* nothing to do */
+		else if (display_fmt == FMT_SINGLE)
+			newline();
+		else {
+			if (nexttab + column_width > terminal_width
+#ifndef FEATURE_AUTOWIDTH
+			|| nexttab + len >= terminal_width
+#endif
+			)
+				newline();
+			else
+				tab(nexttab);
+		}
+		/* work out where next column starts */
+#ifdef FEATURE_AUTOWIDTH
+		/* we know the calculated width is big enough */
+		nexttab = column + column_width + COLUMN_GAP;
+#else
+		/* might cover more than one fixed-width column */
+		nexttab = column;
+		do
+			nexttab += column_width + COLUMN_GAP;
+		while (nexttab < (column + len + COLUMN_GAP));
+#endif
+		/* now write the data */
+		wr(name, len);
+		column = column + len;
+#ifdef FEATURE_FILETYPECHAR
+		if (append)
+			wr(&append, 1), column++;
+#endif
+	}
+}
+
+/**
+ **
+ ** List the given file or directory, expanding a directory
+ ** to show its contents if required
+ **
+ **/
+
+static int list_item(const char *name)
+{
+	struct stat info;
+	DIR *dir;
+	struct dirent *entry;
+	char fullname[MAXNAMLEN+1], *fnend;
+	
+	if (lstat(name, &info))
+		goto listerr;
+	
+	if (!S_ISDIR(info.st_mode) || 
+	    (opts & DIR_NOLIST)) {
+		list_single(name, &info);
+		return 0;
+	}
+
+	/* Otherwise, it's a directory we want to list the contents of */
+
+	if (opts & DISP_DIRNAME) {   /* identify the directory */
+		if (column)
+			wr("\n\n", 2), column = 0;
+		wr(name, strlen(name));
+		wr(":\n", 2);
+	}
+	
+	dir = opendir(name);
+	if (!dir) goto listerr;
+#ifdef FEATURE_AUTOWIDTH
+	column_width = 0;
+	while ((entry = readdir(dir)) != NULL) {
+		short w = strlen(entry->d_name);
+		if (column_width < w)
+			column_width = w;
+	}
+#ifdef HAS_REWINDDIR
+	rewinddir(dir);
+#else
+	closedir(dir);
+	dir = opendir(name);
+	if (!dir) goto listerr;
+#endif
+#endif
+
+	/* List the contents */
+	
+	strcpy(fullname,name);	/* *** ignore '.' by itself */
+	fnend=fullname+strlen(fullname);
+	if (fnend[-1] != '/')
+		*fnend++ = '/';
+	
+	while ((entry = readdir(dir)) != NULL) {
+		const char *en=entry->d_name;
+		if (en[0] == '.') {
+			if (!en[1] || (en[1] == '.' && !en[2])) { /* . or .. */
+				if (!(opts & DISP_DOT))
+					continue;
+			}
+			else if (!(opts & DISP_HIDDEN))
+				continue;
+		}
+		/* FIXME: avoid stat if not required */
+		strcpy(fnend, entry->d_name);
+		if (lstat(fullname, &info))
+			goto direrr; /* (shouldn't fail) */
+		list_single(entry->d_name, &info);
+	}
+	closedir(dir);
+	return 0;
+
+direrr:
+	closedir(dir);	
+listerr:
+	newline();
+	name_and_error(name);
+	return 1;
+}
+
+const char	ls_usage[] = "Usage: ls [-1a"
+#ifdef FEATURE_TIMESTAMPS
+	"c"
+#endif
+	"d"
+#ifdef FEATURE_TIMESTAMPS
+	"e"
+#endif
+	"ln"
+#ifdef FEATURE_FILETYPECHAR
+	"p"
+#endif
+#ifdef FEATURE_TIMESTAMPS
+	"u"
+#endif
+	"xAC"
+#ifdef FEATURE_FILETYPECHAR
+	"F"
+#endif
+#ifdef FEATURE_RECURSIVE
+	"R"
+#endif
+	"] [filenames...]\n";
+
+extern int
+ls_main(struct FileInfo * not_used, int argc, char * * argv)
+{
+	int argi=1, i;
+	
+	/* process options */
+	while (argi < argc && argv[argi][0] == '-') {
+		const char *p = &argv[argi][1];
+		
+		if (!*p) goto print_usage_message;	/* "-" by itself not allowed */
+		if (*p == '-') {
+			if (!p[1]) {	/* "--" forces end of options */
+				argi++;
+				break;
+			}
+			/* it's a long option name - we don't support them */
+			goto print_usage_message;
+		}
+		
+		while (*p)
+			switch (*p++) {
+			case 'l':	display_fmt = FMT_LONG; break;
+			case '1':	display_fmt = FMT_SINGLE; break;
+			case 'x':	display_fmt = FMT_ROWS; break;
+			case 'C':	display_fmt = FMT_COLUMNS; break;
+#ifdef FEATURE_FILETYPECHAR
+			case 'p':	opts |= DISP_FTYPE; break;
+			case 'F':	opts |= DISP_FTYPE|DISP_EXEC; break;
+#endif
+			case 'A':	opts |= DISP_HIDDEN; break;
+			case 'a':	opts |= DISP_HIDDEN|DISP_DOT; break;
+			case 'n':	opts |= DISP_NUMERIC; break;
+			case 'd':	opts |= DIR_NOLIST; break;
+#ifdef FEATURE_RECURSIVE
+			case 'R':	opts |= DIR_RECURSE; break;
+#endif
+#ifdef FEATURE_TIMESTAMPS
+			case 'u':	time_fmt = TIME_ACCESS; break;
+			case 'c':	time_fmt = TIME_CHANGE; break;
+			case 'e':	opts |= DISP_FULLTIME; break;
+#endif
+			default:	goto print_usage_message;
+			}
+		
+		argi++;
+	}
+
+	/* choose a display format */
+	if (display_fmt == FMT_AUTO)
+		display_fmt = isatty(STDOUT_FILENO) ? FMT_COLUMNS : FMT_SINGLE;
+	if (argi < argc - 1)
+		opts |= DISP_DIRNAME; /* 2 or more items? label directories */
+#ifdef FEATURE_AUTOWIDTH
+	/* could add a -w option and/or TIOCGWINSZ call */
+	if (terminal_width < 1) terminal_width = TERMINAL_WIDTH;
+	
+	for (i = argi; i < argc; i++) {
+		int len = strlen(argv[i]);
+		if (column_width < len)
+			column_width = len;
+	}
+#endif
+
+	/* process files specified, or current directory if none */
+	i=0;
+	if (argi == argc)
+		i = list_item(".");
+	while (argi < argc)
+		i |= list_item(argv[argi++]);
+	newline();
+	return i;
+
+print_usage_message:
+	usage(ls_usage);
+	return 1;
+}