blob: 6f0e7f5b6ac50f753da9ec5f3b8652755624be8f (
about) (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
#!@GUILE@ -ds
!#
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2012, 2013, 2014, 2017 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix 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 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix 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 GNU Guix. If not, see <http://www.gnu.org/licenses/>.
;;;
;;; List files being used at run time; these files are garbage collector
;;; roots. This is equivalent to `find-runtime-roots.pl' in Nix.
;;;
(use-modules (ice-9 ftw)
(ice-9 regex)
(ice-9 rdelim)
(srfi srfi-1)
(srfi srfi-26)
(rnrs io ports))
(define %proc-directory
;; Mount point of Linuxish /proc file system.
"/proc")
(define %store-directory
(or (getenv "NIX_STORE_DIR")
"@storedir@"))
(define (proc-file-roots dir file)
"Return a one-element list containing the file pointed to by DIR/FILE,
or the empty list."
(or (and=> (false-if-exception (readlink (string-append dir "/" file)))
list)
'()))
(define proc-exe-roots (cut proc-file-roots <> "exe"))
(define proc-cwd-roots (cut proc-file-roots <> "cwd"))
(define (proc-fd-roots dir)
"Return the list of store files referenced by DIR, which is a
/proc/XYZ directory."
(let ((dir (string-append dir "/fd")))
(filter-map (lambda (file)
(let ((target (false-if-exception
(readlink (string-append dir "/" file)))))
(and target
(string-prefix? "/" target)
target)))
(or (scandir dir string->number) '()))))
(define (proc-maps-roots dir)
"Return the list of store files referenced by DIR, which is a
/proc/XYZ directory."
(define %file-mapping-line
(make-regexp "^.*[[:blank:]]+/([^ ]+)$"))
(call-with-input-file (string-append dir "/maps")
(lambda (maps)
(let loop ((line (read-line maps))
(roots '()))
(cond ((eof-object? line)
roots)
((regexp-exec %file-mapping-line line)
=>
(lambda (match)
(let ((file (string-append "/"
(match:substring match 1))))
(loop (read-line maps)
(cons file roots)))))
(else
(loop (read-line maps) roots)))))))
(define (proc-environ-roots dir)
"Return the list of store files referenced by DIR/environ, where DIR is a
/proc/XYZ directory."
(define split-on-nul
(cute string-tokenize <>
(char-set-complement (char-set #\nul))))
(define (rhs-file-names str)
(let ((equal (string-index str #\=)))
(if equal
(let* ((str (substring str (+ 1 equal)))
(rx (string-append (regexp-quote %store-directory)
"/[0-9a-z]{32}-[a-zA-Z0-9\\._+-]+")))
(map match:substring (list-matches rx str)))
'())))
(define environ
(string-append dir "/environ"))
(append-map rhs-file-names
(split-on-nul
(call-with-input-file environ
get-string-all))))
(define (referenced-files)
"Return the list of referenced store items."
(append-map (lambda (pid)
(let ((proc (string-append %proc-directory "/" pid)))
(catch 'system-error
(lambda ()
(append (proc-exe-roots proc)
(proc-cwd-roots proc)
(proc-fd-roots proc)
(proc-maps-roots proc)
(proc-environ-roots proc)))
(lambda args
;; There's a TOCTTOU race that we need to handle.
(if (= ENOENT (system-error-errno args))
'()
(apply throw args))))))
(scandir %proc-directory string->number
(lambda (a b)
(< (string->number a) (string->number b))))))
(for-each (cut simple-format #t "~a~%" <>)
(delete-duplicates (referenced-files)))
|