home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Languguage OS 2
/
Languguage OS II Version 10-94 (Knowledge Media)(1994).ISO
/
gnu
/
shllutil.lha
/
shellutils-1.8
/
src
/
pathchk.c
< prev
next >
Wrap
C/C++ Source or Header
|
1992-09-10
|
9KB
|
333 lines
/* pathchk -- check whether pathnames are valid or portable
Copyright (C) 1991, 1992 Free Software Foundation, Inc.
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, 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. */
/* Usage: pathchk [-p] [--portability] path...
For each PATH, print a message if any of these conditions are false:
* all existing leading directories in PATH have search (execute) permission
* strlen (PATH) <= PATH_MAX
* strlen (each_directory_in_PATH) <= NAME_MAX
Exit status:
0 All PATH names passed all of the tests.
1 An error occurred.
Options:
-p, --portability Instead of performing length checks on the
underlying filesystem, test the length of the
pathname and its components against the POSIX.1
minimum limits for portability, _POSIX_NAME_MAX
and _POSIX_PATH_MAX in 2.9.2. Also check that
the pathname contains no characters not in the
portable filename character set.
David MacKenzie <djm@gnu.ai.mit.edu>
and Jim Meyering <meyering@cs.utexas.edu> */
#include <stdio.h>
#include <getopt.h>
#include <sys/types.h>
#include "system.h"
#ifdef _POSIX_VERSION
#include <limits.h>
#ifndef PATH_MAX
#define PATH_MAX_FOR(p) pathconf ((p), _PC_PATH_MAX)
#endif /* not PATH_MAX */
#ifndef NAME_MAX
#define NAME_MAX_FOR(p) pathconf ((p), _PC_NAME_MAX);
#endif /* not NAME_MAX */
#else /* not _POSIX_VERSION */
#include <sys/param.h>
#ifndef PATH_MAX
#ifdef MAXPATHLEN
#define PATH_MAX MAXPATHLEN
#else /* not MAXPATHLEN */
#define PATH_MAX _POSIX_PATH_MAX
#endif /* not MAXPATHLEN */
#endif /* not PATH_MAX */
#ifndef NAME_MAX
#ifdef MAXNAMLEN
#define NAME_MAX MAXNAMLEN
#else /* not MAXNAMLEN */
#define NAME_MAX _POSIX_NAME_MAX
#endif /* not MAXNAMLEN */
#endif /* not NAME_MAX */
#endif /* not _POSIX_VERSION */
#ifndef _POSIX_PATH_MAX
#define _POSIX_PATH_MAX 255
#endif
#ifndef _POSIX_NAME_MAX
#define _POSIX_NAME_MAX 14
#endif
#ifndef PATH_MAX_FOR
#define PATH_MAX_FOR(p) PATH_MAX
#endif
#ifndef NAME_MAX_FOR
#define NAME_MAX_FOR(p) NAME_MAX
#endif
char *xstrdup();
int validate_path ();
void error ();
void usage ();
/* The name this program was run with. */
char *program_name;
struct option longopts[] =
{
{"portability", 0, NULL, 'p'},
{NULL, 0, NULL, 0}
};
void
main (argc, argv)
int argc;
char **argv;
{
int exit_status = 0;
int check_portability = 0;
int optc;
program_name = argv[0];
while ((optc = getopt_long (argc, argv, "p", longopts, (int *) 0)) != EOF)
{
switch (optc)
{
case 'p':
check_portability = 1;
break;
default:
usage ();
}
}
if (optind == argc)
usage ();
for (; optind < argc; ++optind)
exit_status |= validate_path (argv[optind], check_portability);
exit (exit_status);
}
/* Each element is nonzero if the corresponding ASCII character is
in the POSIX portable character set, and zero if it is not.
In addition, the entry for `/' is nonzero to simplify checking. */
char portable_chars[] =
{
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0-15 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 16-31 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, /* 32-47 */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, /* 48-63 */
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 64-79 */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, /* 80-95 */
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 96-111 */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, /* 112-127 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};
/* If PATH contains only portable characters, return 1, else 0. */
int
portable_chars_only (path)
char *path;
{
char *p;
for (p = path; *p; ++p)
if (portable_chars[*p] == 0)
{
error (0, 0, "path `%s' contains nonportable character `%c'",
path, *p);
return 0;
}
return 1;
}
/* Return 1 if PATH is a usable leading directory, 0 if not,
2 if it doesn't exist. */
int
dir_ok (path)
char *path;
{
struct stat stats;
if (stat (path, &stats))
return 2;
if (!S_ISDIR (stats.st_mode))
{
error (0, 0, "`%s' is not a directory", path);
return 0;
}
/* Use access to test for search permission because
testing permission bits of st_mode can lose with new
access control mechanisms. Of course, access loses if you're
running setuid. */
if (access (path, X_OK) != 0)
{
if (errno == EACCES)
error (0, 0, "directory `%s' is not searchable", path);
else
error (0, errno, "%s", path);
return 0;
}
return 1;
}
/* Make sure that
strlen (PATH) <= PATH_MAX
&& strlen (each-existing-directory-in-PATH) <= NAME_MAX
If PORTABILITY is nonzero, compare against _POSIX_PATH_MAX and
_POSIX_NAME_MAX instead, and make sure that PATH contains no
characters not in the POSIX portable filename character set, which
consists of A-Z, a-z, 0-9, ., _, -.
Make sure that all leading directories along PATH that exist have
`x' permission.
Return 0 if all of these tests are successful, 1 if any fail. */
int
validate_path (path, portability)
char *path;
int portability;
{
int path_max;
int last_elem; /* Nonzero if checking last element of path. */
int exists; /* 2 if the path element exists. */
char *slash;
char *parent; /* Last existing leading directory so far. */
if (portability && !portable_chars_only (path))
return 1;
if (*path == '\0')
return 0;
/* Figure out the parent of the first element in PATH. */
parent = xstrdup (*path == '/' ? "/" : ".");
slash = path;
last_elem = 0;
while (1)
{
int name_max;
int length; /* Length of partial path being checked. */
char *start; /* Start of path element being checked. */
/* Find the end of this element of the path.
Then chop off the rest of the path after this element. */
while (*slash == '/')
slash++;
start = slash;
slash = index (slash, '/');
if (slash != NULL)
*slash = '\0';
else
{
last_elem = 1;
slash = index (start, '\0');
}
if (!last_elem)
{
exists = dir_ok (path);
if (dir_ok == 0)
{
free (parent);
return 1;
}
}
length = slash - start;
/* Since we know that `parent' is a directory, it's ok to call
pathconf with it as the argument. (If `parent' isn't a directory
or doesn't exist, the behavior of pathconf is undefined.)
But if `parent' is a directory and is on a remote file system,
it's likely that pathconf can't give us a reasonable value
and will return -1. (NFS and tempfs are not POSIX . . .)
In that case, we have no choice but to assume the pessimal
POSIX minimums. */
name_max = portability ? _POSIX_NAME_MAX : NAME_MAX_FOR (parent);
if (name_max < 0)
name_max = _POSIX_NAME_MAX;
if (length > name_max)
{
error (0, 0, "name `%s' has length %d; exceeds limit of %d",
start, length, name_max);
free (parent);
return 1;
}
if (last_elem)
break;
if (exists == 1)
{
free (parent);
parent = xstrdup (path);
}
*slash++ = '/';
}
/* `parent' is now the last existing leading directory in the whole path,
so it's ok to call pathconf with it as the argument. */
path_max = portability ? _POSIX_PATH_MAX : PATH_MAX_FOR (parent);
if (path_max < 0)
path_max = _POSIX_PATH_MAX;
free (parent);
if (strlen (path) > path_max)
{
error (0, 0, "path `%s' has length %d; exceeds limit of %d",
path, strlen (path), path_max);
return 1;
}
return 0;
}
void
usage ()
{
fprintf (stderr, "\
Usage: %s [-p] [--portability] path...\n",
program_name);
exit (1);
}