#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <strings.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>

#define USAGE "usage: lss [-aAmMcCsSh] [-f fmt] file....\n"

main(int argc, char **argv)
{
	struct stat	stat_buf;
	int		fmts=0, i, j, c, errflg = 0;
	extern char	*optarg;
	extern int	optind;
	char		fmt[50] = "";
	char		*time_fmt = NULL;
	char		*buff = NULL;
	size_t		buff_size;

	while ((c = getopt(argc, argv, "haAmMcCsSf:")) != EOF) {
	  if (index("aAmMcCsS", c) != 0) {
	    if (fmts < (sizeof(fmt)-1))
	      fmt[fmts++] = (char) c;
	    fmt[fmts] = (char) 0;
	  }
	  else if ((char) c == 'f') {
	    time_fmt=optarg;
	  }
	  else if ((char) c == 'h') {
	    printf(USAGE);
	    printf("Options:"\
		   "	-h	Display this help\n"\
		   "	-a	Access time in seconds\n"\
		   "	-A	Access time in human format\n"\
		   "	-m	Modify time in seconds\n"\
		   "	-M	Modify time in human format\n"\
		   "	-c	Inode Change time in seconds\n"\
		   "	-C	Inode Change time in human format\n"\
		   "	-f	Specify format for human readable times\n"\
		   "	-s	Size in bytes\n"\
		   "	-S	Space used in blocks\n"\
	    );
	    exit(0);
	  }
	  else {
	    errflg++;
	  }
	}

	if (argc < 2) {
	  fprintf(stderr, "No Files given\n");
	  errflg++;
	}

	if (errflg) {
	  fprintf(stderr, USAGE);
	  exit(1);
	}

	if (time_fmt == NULL) {
	  time_fmt = "%Y-%m-%d %T";
	}

	/*  Guess Size for buff */
	buff_size = strlen(time_fmt)*8 + 80;
	while (buff = (char *) malloc(buff_size)) {
	    /*  Check that format will fit into only half the space  */
	    if (strftime(buff, buff_size/2, time_fmt, localtime((time_t*)&buff_size)))
	      break ;
	    free(buff);
	    buff_size += buff_size;
	}

	for (i=optind; i<argc; i++) {
	  if (stat(argv[i], &stat_buf) != 0)
	    perror(argv[i]);
	  else
	    if (fmts==0) {
	      printf("%10d %10d %10d ",
		stat_buf.st_atime,
		stat_buf.st_mtime,
		stat_buf.st_ctime);
	    }
	    for (j=0; j<fmts; j++) {
	      switch (fmt[j]) {
	       case 'a':	printf("%10d ", stat_buf.st_atime) ; break ;
	       case 'm':	printf("%10d ", stat_buf.st_mtime) ; break ;
	       case 'c':	printf("%10d ", stat_buf.st_ctime) ; break ;
	       case 's':	printf("%8d ", stat_buf.st_size) ; break ;
	       case 'S':	printf("%6d ", stat_buf.st_blocks) ; break ;
	       case 'A':	strftime(buff, buff_size, time_fmt, localtime(&stat_buf.st_atime));
				printf(" %s ", buff) ; break ;
	       case 'M':	strftime(buff, buff_size, time_fmt, localtime(&stat_buf.st_mtime));
				printf(" %s ", buff) ; break ;
	       case 'C':	strftime(buff, buff_size, time_fmt, localtime(&stat_buf.st_ctime));
				printf(" %s ", buff) ; break ;
	      }
	    }
	    printf(" %s\n", argv[i]);
	}
	exit(0);
}