From a670b0b4aed129dc11b465c1c330bfe9202023e5 Mon Sep 17 00:00:00 2001
From: Michael Forney <forney@google.com>
Date: Sun, 18 Mar 2018 17:54:02 -0700
Subject: kbuild: Use ls(1) instead of stat(1) to obtain file size

stat(1) is not standardized and different implementations have their own
(conflicting) flags for querying the size of a file.

ls(1) provides the same information (value of st.st_size) in the 5th
column, except when the file is a character or block device. This output
is standardized[0]. The -n option turns on -l, which writes lines
formatted like

  "%s %u %s %s %u %s %s\n", <file mode>, <number of links>,
      <owner name>, <group name>, <size>, <date and time>,
      <pathname>

but instead of writing the <owner name> and <group name>, it writes the
numeric owner and group IDs (this avoids /etc/passwd and /etc/group
lookups as well as potential field splitting issues).

The <size> field is specified as "the value that would be returned for
the file in the st_size field of struct stat".

To avoid duplicating logic in several locations in the tree, create
scripts/file-size.sh and update callers to use that instead of stat(1).

[0] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/ls.html#tag_20_73_10

Signed-off-by: Michael Forney <forney@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
---
 scripts/file-size.sh | 4 ++++
 1 file changed, 4 insertions(+)
 create mode 100755 scripts/file-size.sh

(limited to 'scripts/file-size.sh')

diff --git a/scripts/file-size.sh b/scripts/file-size.sh
new file mode 100755
index 000000000000..7eb7423416b5
--- /dev/null
+++ b/scripts/file-size.sh
@@ -0,0 +1,4 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+set -- $(ls -dn "$1")
+printf '%s\n' "$5"
-- 
cgit v1.2.3