/* $Id: filetime.c,v 1.1 2005/11/27 22:01:41 sms Exp $
 * www.pccl.demon.co.uk
 */
#include	<sys/types.h>
#include	<sys/stat.h>

#include	<errno.h>
#include	<libgen.h>
#include	<stdio.h>
#include	<unistd.h>

static char	*sProgName	= NULL;

enum Format {
	  EPOCH
	, STRFTIME
	};

enum Property {
	  ACCESS_TIME
	, MOD_TIME
	, STATUS_TIME
	};

static int displayTime (
	  char		*aFile		/* File to show			*/
	, enum Property	aProperty	/* Which time to show		*/
	, enum Format	aFormat		/* Display format		*/
	, char		*aFormatString	/* Format string		*/
	)
{
	struct stat	lStat;		/* File status			*/
	int	lRet	= 0;		/* Return code			*/

	if (stat (aFile, &lStat) < 0)
	{
		lRet	= errno;
		fprintf(stderr, "Cannot stat %s, %s\n"
				, aFile
				, strerror (errno)
				);
}
	else
	{
		time_t	lTime;			/* Raw time		*/
		char	lDisplayTime[80];	/* Data to display	*/

		/*
                 * Pick up the value we want.
		 */
		switch (aProperty)
		{
			case ACCESS_TIME:
				lTime	= lStat.st_atime;
				break;
			case MOD_TIME:
				lTime	= lStat.st_mtime;
				break;
			case STATUS_TIME:
				lTime	= lStat.st_ctime;
				break;
		}

		switch (aFormat)
		{
			case EPOCH:
				(void) sprintf(lDisplayTime, "%ld", lTime);
				break;
			case STRFTIME:
				{
					(void) strftime (lDisplayTime
							, sizeof (lDisplayTime)
							, aFormatString
							, localtime (&lTime)
							);
				break;
				}
		}

		(void) printf("%s:	%s\n", aFile, lDisplayTime);
	}

	return (lRet);
}

/*
 * Display the usage message
 */
static void usage (
	  FILE	*aFp		/* Stream to write			*/
	)
{
	fprintf (aFp, "USAGE:\n");
	fprintf (aFp, "    %s -[a|c|m] -[e|s format] -h file\n", sProgName);
	fprintf (aFp, "        -a    display last access time\n");
	fprintf (aFp, "        -e    display seconds since epoch (default)\n");
	fprintf (aFp, "        -c    display last status change time\n");
	fprintf (aFp, "        -h    help\n");
	fprintf (aFp, "        -m    display last modification time (default)\n");
	fprintf (aFp, "        -s    display strftime() format\n");
}

/*
 * This displays the time stamp of the named file.
 */
int main (
	  int	aArgc		/* Argument count			*/
	, char	*aArgv[]	/* Arguments				*/
	)
{
	char	lOpt;		/* Command line option			*/
	int	lArgIdx;	/* Index through command line		*/
	int	lExit	= 0;	/* Exit code				*/
	enum Property	lProperty	= STATUS_TIME;	/* Which time?	*/
	enum Format	lFormat		= EPOCH;	/* Which format?*/
	char		*lFormatString	= NULL;		/* Format string*/

	/*
	 * Parse the command line
	 */
	sProgName	= basename (aArgv[0]);

	while ((lOpt = getopt (aArgc, aArgv, "acehms:")) != -1)
	{
		switch (lOpt)
		{
			case 'a':
				lProperty	= ACCESS_TIME;
				break;
			case 'c':
				lProperty	= STATUS_TIME;
				break;
			case 'e':
				lFormat		= EPOCH;
				break;
			case 'h':
				usage (stdout);
				exit (EINVAL);
				break;
			case 'm':
				lProperty	= MOD_TIME;
				break;
			case 's':
				lFormat		= STRFTIME;
				lFormatString	= optarg;
				break;
			case '?':
				fprintf (stderr
					, "Unrecognised option: -%c\n"
					, optopt
					);
				usage (stderr);
				exit (EINVAL);
		}
	}

	/*
	 * Process the file
	 */
	for (lArgIdx = optind; lArgIdx < aArgc; lArgIdx++)
	{
		lExit	= displayTime(aArgv[lArgIdx]
					, lProperty
					, lFormat
					, lFormatString
					);
	}


	exit (lExit);
}