/* From AUUGN Feb 1998 

tidypath.c	- tidy up a long $PATH

Copyright 1998 David Purdue David.Purdue@computer.org
*/

#ifdef __hpux
#define _INCLUDE_POSIX_SOURCE
#define _INCLUDE_HPUX_SOURCE
#define _INCLUDE_XOPEN_SOURCE
#endif

#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <sys/types.h>
/*#include <sys/stat.h>*/
#include <unistd.h>
#include <errno.h>

void main(int argc, char *argv[]) {
  char **final_path, *path_ptr, *end_dir;
  int	num_colons, i, j, num_dirs, dir_length, found;
  /*  struct stat sbuf; */
  
  if (argc != 2) { /* no options supported at present ! */
    fprintf(stderr,"Usage:\n"
	    "csh> setenv PATH `%s $PATH`\n"
	    "sh$  export PATH=`%s $PATH`\n",
	    argv[0], argv[0]);
    exit(1);
  }
  
  /* count the number of colons in the path */
  num_colons = 0;
  path_ptr = index(argv[1], ':');
  while (path_ptr != NULL) {
    num_colons++;
    path_ptr++;
    path_ptr = index(path_ptr, ':');
  }

  /* there will never be more directories out than in. */
  final_path = (char **) calloc(num_colons + 1, sizeof(char *));
  path_ptr = argv[1];
  num_dirs = 0;

  /* load up the path */
  while (path_ptr != NULL) {
    /*printf("Starting[%d]=>%s\n", num_dirs, path_ptr);*/
    end_dir = index(path_ptr, ':');

    if (end_dir == NULL) {
      dir_length = strlen(path_ptr);
    } else {
      dir_length = end_dir - path_ptr;
    }
    if (dir_length <= 0 ) {
      fprintf(stderr, "empty directory encountered on unique dir %d\n",
	      num_dirs);
      path_ptr++;
      continue;
    }
    found = 0;
    for (j = 0; j < num_dirs; j++) {
      /* if (strcmp (path_ptr, final_path[j]) == 0) {*/
      if (strncmp (path_ptr, final_path[j], dir_length) == 0) {
	if (strlen(final_path[j]) != dir_length) {
	  fprintf(stderr,"%s != %s\n", final_path[j], path_ptr);
	  continue;
	}
	found = 1;
	break;
      }
    }
    
    if (found == 0) {
      final_path[num_dirs] = malloc(dir_length + 1);
      if (NULL == final_path[num_dirs]) {
	perror("malloc");
	exit (errno);
      }
      strncpy(final_path[num_dirs], path_ptr, dir_length);
      final_path[num_dirs][dir_length] = '\0';
      /*printf("++%s++\n", final_path[num_dirs]);*/

      if (0 == access(final_path[num_dirs], X_OK)) {
	num_dirs ++;
      } else {
	perror(final_path[num_dirs]);
	free(final_path[num_dirs]);
      }
    }
    
    if (end_dir == NULL) {
      path_ptr = NULL;
    } else {
      end_dir++;
      path_ptr = end_dir;
    }
  }

  /* Write out the path */
  for(i = 0; i < (num_dirs - 1); i++) {
    printf("%s:", final_path[i]);
  }
  printf("%s\n", final_path[num_dirs-1]);
  
  exit(0);
}