commit c1aa247e85a70aec8f2ec38845a666d40aa6a077
Author: heinzel <heinzel>
Date:   Tue Feb 19 14:12:59 2008 +0000

    Added my implementation of unixtime.
    This implementation has very few reasonable code (call atol() and ctime()),
    but has some nice standard program stuff (parse options, print help, ...).

diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000..ebe4fc5
--- /dev/null
+++ b/COPYING
@@ -0,0 +1 @@
+This is public domain, I think.
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..4ec4489
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,5 @@
+help:
+	@echo "Run ./configure first!"
+	@echo "Or even better: take a look at the file README."
+install: help
+all: help
diff --git a/Makefile.dist b/Makefile.dist
new file mode 100644
index 0000000..4ec4489
--- /dev/null
+++ b/Makefile.dist
@@ -0,0 +1,5 @@
+help:
+	@echo "Run ./configure first!"
+	@echo "Or even better: take a look at the file README."
+install: help
+all: help
diff --git a/Makefile.in b/Makefile.in
new file mode 100644
index 0000000..a4f7e0e
--- /dev/null
+++ b/Makefile.in
@@ -0,0 +1,72 @@
+# @Makefile.in@
+
+PREFIX  := @PREFIX@
+BINDIR  := @BINDIR@
+MAN1DIR := @MAN1DIR@
+
+MAIN := unixtime
+OBJS := unixtime.o
+#LIBS :=
+MAN1 := unixtime.1
+
+MANGZ := @MANGZ@
+ifeq ($(MANGZ), 1)
+ MAN1 := $(addsuffix .gz, $(MAN1))
+endif
+
+CC      := @CC@
+CP      := @CP@
+GZIP	:= @GZIP@
+INSTALL := @INSTALL@
+RM      := @RM@
+STRIP   := @STRIP@
+TAR     := @TAR@
+
+.PHONY: help strip install install-bin install-man install-man1 uninstall \
+	clean distclean mrproper dist
+.DEFAULT: $(MAIN)
+
+$(MAIN):	$(OBJS)
+ifeq (@STATIC@, 1)
+	$(CC) --static -g -o $(MAIN) $(LIBS) $(OBJS)
+else
+	$(CC) -g -o $(MAIN) $(LIBS) $(OBJS)
+endif
+
+%.o : %.c
+	$(CC) $(CFLAGS) $(CPPFLAGS) -c $< -o $@
+
+help:
+	@echo "There is no help."
+
+strip:	$(MAIN)
+	$(STRIP) $(MAIN)
+
+install:	install-bin install-man
+
+install-bin:	strip
+	$(INSTALL) $(MAIN) $(BINDIR)
+
+install-man:	install-man1
+
+install-man1:	$(MAN1)
+	$(INSTALL) $^ $(MAN1DIR)
+
+%.gz : %
+	$(GZIP) -c $< > $@
+
+uninstall:
+	-$(RM) $(BINDIR)/$(MAIN)
+	cd $(MAN1DIR) ; -$(RM) $(MAN1)
+
+clean:
+	$(RM) -f *.o $(MAIN)
+
+distclean:	clean
+	$(CP) Makefile.dist Makefile
+mrproper:	distclean
+
+dist:	distclean
+	cd .. ; $(TAR) -czf $(notdir $(PWD)).tar.gz $(notdir $(PWD))
+
+#end
diff --git a/README b/README
new file mode 100644
index 0000000..b9959d0
--- /dev/null
+++ b/README
@@ -0,0 +1,9 @@
+unixtime(1) converts a unix timestamp (number of seconds since epoch) 
+into a human readable date.
+
+INSTALL
+=======
+./configure
+make
+make install
+
diff --git a/configure b/configure
new file mode 100755
index 0000000..0f72572
--- /dev/null
+++ b/configure
@@ -0,0 +1,291 @@
+#!/bin/sh
+#
+# configure
+#
+# A simple script to configure Makefiles
+# (i.e. read Makefile.in, replace strings and write Makefile).
+#
+# heinzel <heinzel@heinzelwelt.de>
+#
+# $Id: configure,v 1.1 2008/02/19 14:12:59 heinzel Exp $
+#
+VERSION='configure Version 0.1 $Revision: 1.1 $ ($Date: 2008/02/19 14:12:59 $ $Author: heinzel $)'
+
+### config ###
+FILES=""
+FILES_DEF="configure.files"
+
+TEMPLATE_SUFFIX=".in"
+MACROS_DEF="configure.macros"
+
+MACROS="CTEMPLATE"
+MACRO_CTEMPLATE="@CFILE@ (created by configure script)"
+
+### functions ###
+function print_help() {
+	cat <<EOH
+configure create files by processing templates and replace macros.
+For now macros are simple name-value pairs. Use strings like @NAME@ within
+the template files and configure will replace those strings by the named
+value while creating the resulting files.
+
+Usage: ./configure [OPTIONS]
+
+Options:
+  -h, --help
+  -V, --version
+
+Generic Options (and default values):
+EOH
+	for m in $MACROS ; do
+		case "$m" in
+		CFILE|CTEMPLATE)
+			continue
+			;;
+		esac
+
+		name="`echo $m | tr [[:upper:]] [[:lower:]]`"
+		text="`eval_macro $m`"
+		case "$text" in
+		0)
+			output="  --without-${name}"
+			;;
+		1)
+			output="  --with-${name}"
+			;;
+		*)
+			output="  --${name} $text"
+			;;
+		esac
+		echo "$output"
+	done
+	echo ""
+	cat <<EOH
+Files:
+  This script will create following files: $FILES
+  or read file names to create from '$FILES_DEF'
+  The templates have to end with '$TEMPLATE_SUFFIX'
+  The macros can be defined in '$MACROS_DEF'
+EOH
+}
+
+function print_version() {
+	echo "$VERSION"
+}
+
+function set_macro() {
+	case "$1" in
+	'')
+		return 1
+		;;
+	--with-*|--enable-*)
+		name="`echo $1 | cut -f1 -d= | cut -f4- -d- | tr [[:lower:]] [[:upper:]]`"
+		text="1"
+		;;
+	--without-*|--disable-*)
+		name="`echo $1 | cut -f1 -d= | cut -f4- -d- | tr [[:lower:]] [[:upper:]]`"
+		text="0"
+		;;
+	--*=*)
+		name="`echo $1 | cut -f1 -d= | cut -c3- | tr [[:lower:]] [[:upper:]]`"
+		text="`echo $1 | cut -f2- -d=`"
+		;;
+	--*)
+		name="`echo $1 | cut -c3- | tr [[:lower:]] [[:upper:]]`"
+		text="$2"
+		;;
+	*=*)
+		name="`echo $1 | cut -f1 -d= | tr [[:lower:]] [[:upper:]]`"
+		text="`echo $1 | cut -f2- -d=`"
+		;;
+	*)
+		name="`echo $1 | tr [[:lower:]] [[:upper:]]`"
+		text=""
+		;;
+	esac
+	eval MACRO_${name}=${text}
+	if ! expr " $MACROS " : ".* $name .*" >/dev/null ; then
+		MACROS="$MACROS ${name}"
+	fi
+}
+
+function eval_macro() {
+	local name="$1"
+	local text=""
+	local return=""
+
+	eval text="\$MACRO_${name}"
+	while : ; do
+		# Test if text contains more macros.
+		echo "$text" | grep -E "@[A-Z][A-Z0-9]*@" >/dev/null
+		r=$?
+		if test "1${r}" != "10" ; then
+			# Text is macro free.
+			return="$text"
+			break
+		else
+			# Get the last macro name from text...
+			sm_name="`echo $text | sed -e 's=^.*@\([A-Z][A-Z0-9]*\)@.*$=\1='`"
+			# Resolve it...
+			sm_text="`eval_macro $sm_name`"
+			# Substitute macro...
+			text="`echo $text | sed -e 's=@'${sm_name}'@='${sm_text}'=g'`"
+		fi
+	done
+
+	echo "$return"
+}
+
+function load_defaults() {
+	local inc="${MACROS_DEF:-configure.macros}"
+	local i=0
+	local line=""
+
+	if test "X${inc}" = "X" ; then
+		return 1
+	fi
+	if test ! -r "$inc" -o -d "$inc" ; then
+		echo "${inc}: not a readable file." >&2
+		return 1
+	fi
+
+	while read line ; do
+		i="`expr $i + 1`"
+		case "$line" in
+		\#*|\ *|'')
+			continue
+			;;
+		*=*)
+			set_macro "$line"
+			;;
+		*)
+			echo "Warning: $inc: unexpected line ($i)." >&2
+			;;
+		esac
+	done < "$inc"
+}
+
+function configure() {
+	local file="$1"
+	local ext="${TEMPLATE_SUFFIX:-.in}"
+	local template=""
+
+	local static_file=""
+
+	local expr=""
+	local name=""
+	local text=""
+
+	if test "X${file}" = "X" ; then
+		echo "No filename given." >&2
+		return 1
+	fi
+	template="${file}${ext}"
+	if test ! -r "$template" -o -d "$template" ; then
+		echo "$file: cannot read template ($template)."
+		return 1
+	fi
+
+	set_macro CFILE="$file"
+	ctext="`eval_macro CTEMPLATE`"
+	cexpr="s=@${template}@=${ctext}=g"
+
+	if test "X${CONFIGURE_STATIC_FILE}" != "X" ; then
+		static_file="$CONFIGURE_STATIC_FILE"
+		read expr < "$static_file"
+	else
+		static_file="`mktemp configure.tmp.XXXXXX`"
+		if test "1$?" -ne "10" -o "X${static_file}" = "X" \
+			-o ! -w "$static_file" ; then
+			echo "Cannot create temp file." >&2
+			return 1
+		fi
+		CONFIGURE_STATIC_FILE="$static_file"
+
+		expr=""
+		for name in $MACROS ; do
+			case "$name" in
+			CFILE|CTEMPLATE)
+				continue
+				;;
+			esac
+			text="`eval_macro $name`"
+			expr="s=@$name@=$text=g
+$expr"
+		done
+
+		echo "$expr" > "$static_file"
+	fi
+
+	sed -e "$cexpr" -e "$expr" "$template" > "$file"
+}
+
+function clean_up() {
+	if test "X${CONFIGURE_STATIC_FILE}" != "X" -a -f "$CONFIGURE_STATIC_FILE" ; then
+		rm "$CONFIGURE_STATIC_FILE"
+	fi
+}
+
+### set options ###
+load_defaults
+
+while test "1$#" -gt "10" ; do
+case "$1" in
+-h|--help)
+	print_help
+	exit 0
+	;;
+-V|--version)
+	print_version
+	exit 0
+	;;
+--with-*|--without-*)
+	set_macro "$1"
+	shift
+	;;
+--enable-*|--disable-*)
+	set_macro "$1"
+	shift
+	;;
+--*=*)
+	set_macro "$1"
+	shift
+	;;
+--*)
+	case "$2" in
+	''|-*)
+		set_macro "${1}=1"
+		shift
+		;;
+	*)
+		set_macro "$1" "$2"
+		shift
+		shift
+		;;
+	esac
+	;;
+esac
+done
+
+### action ###
+
+files="$FILES"
+if test "X${FILES_DEF}" != "X" -a -f "$FILES_DEF" ; then
+	read buf < "$FILES_DEF"
+	files="$files $buf"
+fi
+
+
+if test "X${files}" = "X" ; then
+	echo "No files to configure." >&2
+	echo " Make sure '$FILES_DEF' is there and readable." >&2
+	exit 1
+fi
+
+for f in $files ; do
+	echo "Creating file $f..."
+	configure $f
+done
+
+clean_up
+### end ###
diff --git a/configure.files b/configure.files
new file mode 100644
index 0000000..f3c7a7c
--- /dev/null
+++ b/configure.files
@@ -0,0 +1 @@
+Makefile
diff --git a/configure.macros b/configure.macros
new file mode 100644
index 0000000..80912f3
--- /dev/null
+++ b/configure.macros
@@ -0,0 +1,35 @@
+# configure.macros
+
+# Directories
+PREFIX="/usr/local"
+BINDIR="@PREFIX@/bin"
+SBINDIR="@PREFIX@/sbin"
+MANDIR="@PREFIX@/share/man"
+MAN1DIR="@MANDIR@/man1"
+MAN2DIR="@MANDIR@/man2"
+MAN3DIR="@MANDIR@/man3"
+MAN4DIR="@MANDIR@/man4"
+MAN5DIR="@MANDIR@/man5"
+MAN6DIR="@MANDIR@/man6"
+MAN7DIR="@MANDIR@/man7"
+MAN8DIR="@MANDIR@/man8"
+MAN9DIR="@MANDIR@/man9"
+
+# Programms
+CAT="cat"
+CC="cc"
+CP="cp"
+GZIP="gzip"
+INSTALL="install"
+RM="rm"
+SHELL="/bin/sh"
+STRIP="strip"
+TAR="tar"
+ZCAT="zcat"
+
+# Magic macros
+# @CFILE@ will be expanded to the name of the file, that will be created.
+# Also the current template name (e.g. @Makefile.in@) can be used as a macro
+# that will be expanded to another macro named CTEMPLATE (which can be 
+# defined here or will default to a buildin text).
+#end
diff --git a/unixtime.1 b/unixtime.1
new file mode 100644
index 0000000..8e7f06d
--- /dev/null
+++ b/unixtime.1
@@ -0,0 +1,25 @@
+.\" unixtime.1
+.TH UNIXTIME 1 "Feb. 2008" "heinzel"
+
+.SH NAME
+unixtime \- converts a unix timestamp into a human readable date
+
+.SH SYNOPSIS
+.B unixtime [-h, --help] [-V, --version] <TIMESTAMP>
+
+.SH DESCRIPTION
+\fBunixtime\fP is similar to the standard c library function \fBctime()\fP
+
+.SH OPTIONS
+An integer <TIMESTAMP>, which is a number of seconds since the Epoch.
+
+.SH "BUGS"
+Since I have no real understanding of C, I am sure, there are.
+
+.SH "AUTHOR"
+heinzel <heinzel@heinzelwelt.de>
+
+.SH "SEE ALSO"
+.BR time (2), 
+.BR ctime (3)
+
diff --git a/unixtime.c b/unixtime.c
new file mode 100644
index 0000000..80337be
--- /dev/null
+++ b/unixtime.c
@@ -0,0 +1,138 @@
+/*
+ * unixtime.c
+ */
+
+#include <libgen.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+#include <time.h>
+
+/* symbols */
+#define TRUE 1
+#define FALSE 0
+#define VERSION "0.1"
+
+/* prototypes */
+int  print_version(void);
+int  print_help(void);
+
+/* definition of extern objects */
+char       *progname;
+const char *version  = VERSION;
+
+/*
+ * main
+ */
+int main(int argc, char** argv) {
+	int			i;
+	int			j;
+	char		c;
+	char		*p;
+	size_t      l;
+	time_t		t = 0;
+	struct tm	*tm;
+
+	/* Store program name without path
+	 * (will be used in e.g. error messages) */
+	if( (progname = strdup(basename(argv[0]))) == NULL ) {
+		fprintf(stderr, "%s: ", basename(argv[0]));
+		perror(NULL);
+		exit(EX_OSERR);
+	}
+
+	/* Parse command line options */
+	for( i = 1 ; i < argc ; i++ ) {
+		if(!strncmp("--", argv[i], 2)) {
+		/* Current argument is a GNU long option */
+			if(!strcmp(       "--help", argv[i])) {
+				print_help();
+				exit(EX_OK);
+			} else if(!strcmp("--version", argv[i])) {
+				print_version();
+				exit(EX_OK);
+			} else {
+				fprintf(stderr, "%s: invalid option: %s\n", progname, argv[i]);
+				fprintf(stderr, "Try '%s -h' for help.\n", progname);
+				exit(EX_USAGE);
+			}
+		} else if(!strncmp("-", argv[i], 1)) {
+		/* Current argument is one or more short options */
+			p = argv[i];
+			for( j = 1 ; (c = p[j]) != '\0' ; j++) {
+				switch(c) {
+				case 'h':
+					print_help();
+					exit(EX_OK);
+					break;
+				case 'V':
+					print_version();
+					exit(EX_OK);
+					break;
+				default:
+					fprintf(stderr, "%s: invalid option: %c\n", progname, c);
+					fprintf(stderr, "Try '%s -h' for help.\n", progname);
+					exit(EX_USAGE);
+				}
+			}
+		} else {
+			/* This is the first argument, that is not an option. 
+			 * It will be taken as timestamp. */
+			t = atol(argv[i]);
+			l = strlen(argv[i]);
+			if((p = malloc(l + 1)) != NULL) {
+				snprintf(p, l + 1, "%d", t);
+				if(strcmp(argv[i], p)) {
+					fprintf(stderr, "%s: not numeric: %s\n", progname, 
+						argv[i]);
+					exit(EX_DATAERR);
+				}
+				free(p);
+			} else {
+				fprintf(stderr, "%s: Warning: cannot allocate memory"
+					" to do numeric test on input.\n", progname);
+			}
+			break;
+		}
+	} 		
+
+	p = ctime((& t));
+	if(p == NULL) {
+		fprintf(stderr, "%s: unrecognized date '%d'.\n", progname, time);
+		exit(EX_DATAERR);
+	}
+	fputs(p, stdout);
+	exit(EX_OK);
+}
+
+int print_version( void ) {
+	printf("%s Version %s\n",progname, version);
+	return TRUE;
+}
+
+int print_help( void ) {
+	time_t	t = 0;
+	char	*p;
+	char	*p2;
+
+	printf("\n");
+	printf("%s converts a unix timestamp into a human readable date.\n", 
+		progname);
+	printf("\n");
+	printf("Usage: unixtime [-h, --help] [-V, --version] <TIMESTAMP>\n");
+	printf("\n");
+	printf("Where <TIMESTAMP> is the number of seconds since the Epoch\n");
+	if((p = strdup(ctime(& t))) != NULL) {
+		/* ctime() return the date as string with an appended new line.
+		 * Since we do not want the new line to be printed, we terminate
+		 * the string at the position of the new line. */
+		if((p2 = strstr(p, "\n")) != NULL)
+			strcpy(p2, "\0");
+		printf("(i.e. %s).\n", p);
+		free(p);
+	}
+	printf("\n");
+
+	return TRUE;
+}