---
name: "Lintian::Util"
section: "3"
platform: "linux"
package: "lintian"
version: "2.122.0"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Lintian::Util"
---

# Lintian::Util(3)

Lintian utility functions

## NAME

Lintian::Util - Lintian utility functions

## SYNOPSIS

```
 use Lintian::Util;
```

## DESCRIPTION

This module contains a number of utility subs that are nice to have, but on their own did not warrant their own module.

Most subs are imported only on request.

## VARIABLES

- $PKGNAME\_REGEX

  Regular expression that matches valid package names.  The expression is not anchored and does not enforce any "boundary" characters.

- $PKGREPACK\_REGEX

  Regular expression that matches "repacked" package names.  The expression is not anchored and does not enforce any "boundary" characters. It should only be applied to the upstream portion (see #931846).

- $PKGVERSION\_REGEX

  Regular expression that matches valid package versions.  The expression is not anchored and does not enforce any "boundary" characters.

## FUNCTIONS

- drain\_pipe(FD)

  Reads and discards any remaining contents from FD, which is assumed to be a pipe.  This is mostly done to avoid having the "write"-end die with a SIGPIPE due to a "broken pipe" (which can happen if you just close the pipe).

  May cause an exception if there are issues reading from the pipe.

  Caveat: This will block until the pipe is closed from the "write"-end, so only use it with pipes where the "write"-end will eventually close their end by themselves (or something else will make them close it).

- get\_file\_digest(ALGO, FILE)

  Creates an ALGO digest object that is seeded with the contents of FILE.  If you just want the hex digest, please use "get\_file\_checksum(ALGO, FILE)" instead.

  ALGO can be 'md5' or shaX, where X is any number supported by Digest::SHA (e.g. 'sha256').

  This sub is a convenience wrapper around Digest::{MD5,SHA}.

- get\_file\_checksum(ALGO, FILE)

  Returns a hexadecimal string of the message digest checksum generated by the algorithm ALGO on FILE.

  ALGO can be 'md5' or shaX, where X is any number supported by Digest::SHA (e.g. 'sha256').

  This sub is a convenience wrapper around Digest::{MD5,SHA}.

- perm2oct(PERM)

  Translates PERM to an octal permission.  PERM should be a string describing the permissions as done by *tar t* or *ls -l*.  That is, it should be a string like "-rw-r--r--".

  If the string does not appear to be a valid permission, it will cause a trappable error.

  Examples:

  ```
   # Good
   perm2oct('-rw-r--r--') == oct(644)
   perm2oct('-rwxr-xr-x') == oct(755)
   # Bad
   perm2oct('broken')      # too short to be recognised
   perm2oct('-resurunet')  # contains unknown permissions
  ```

- human\_bytes(SIZE)

  - locate\_executable (CMD)

  - drop\_relative\_prefix(STRING)

  Remove an initial ./ from STRING, if present

- version\_from\_changelog

  - match\_glob( $glob, @things\_to\_test )

  Resembles the same semantic as Text::Glob's **match\_glob()**, but with the proper escaping of Regexp::Wildcards and pre-configured for Lintian's purpose. No more directly having to access module variables either.

- normalize\_pkg\_path(PATH)

  Normalize PATH by removing superfluous path segments.  PATH is assumed to be relative the package root.  Note that the result will never start nor end with a slash, even if PATH does.

  As the name suggests, this is a path "normalization" rather than a true path resolution (for that use Cwd::realpath).  Particularly, it assumes none of the path segments are symlinks.

  normalize\_pkg\_path will return `"q{}"` (i.e. the empty string) if PATH is normalized to the root dir and `"undef"` if the path cannot be normalized without escaping the package root.

- normalize\_link\_target(CURDIR, LINK\_TARGET)

  Normalize the path obtained by following a link with LINK\_TARGET as its target from CURDIR as the current directory.  CURDIR is assumed to be relative to the package root.  Note that the result will never start nor end with a slash, even if CURDIR or DEST does.

  normalize\_pkg\_path will return `"q{}"` (i.e. the empty string) if the target is the root dir and `"undef"` if the path cannot be normalized without escaping the package root.

  **CAVEAT**: This function is *not always sufficient* to test if it is safe to open a given symlink. Use `"is_ancestor_of(PARENTDIR, PATH)"` for that.  If you must use this function, remember to check that the target is not a symlink (or if it is, that it can be resolved safely).

- is\_ancestor\_of(PARENTDIR, PATH)

  Returns true if and only if PATH is PARENTDIR or a path stored somewhere within PARENTDIR (or its subdirs).

  This function will resolve the paths; any failure to resolve the path will cause a trappable error.

- read\_md5sums

  - unescape\_md5sum\_filename

  - utf8\_clean\_log

  - utf8\_clean\_bytes

  ## SEE ALSO

[**lintian**(1)](/lintian/1.md)