copy-builtin: posix conformance

This commits contains changes to allow running `copy-builtin` without
bash + some minor improvements.

changed shebang to /bin/sh
added -f option to `set` to globally disable unneeded globbing
replaced all `echo` commands within add_after() with `printf`
alternative to avoid possible issues with options (-neE)
dropped non-portable superfluous `readlink` command
replaced superfluous `true` command with `:` builtin alternative
replaced non-portable `--recursive` option of `cp` command with `-R`
alternative
dropped non-portable `local` keyword

Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: illiliti <[email protected]>
Closes #12004

1 files changed, 20 insertions, 25 deletions

diff --git a/copy-builtin b/copy-builtin
index 36e19545d..cd6f25909 100755
--- a/copy-builtin
+++ b/copy-builtin
@@ -1,6 +1,6 @@
-#!/usr/bin/env bash
+#!/bin/sh
 
-set -e
+set -ef
 
 usage()
 {
@@ -9,26 +9,25 @@ usage()
 }
 
 [ "$#" -eq 1 ] || usage
-KERNEL_DIR="$(readlink --canonicalize-existing "$1")"
+KERNEL_DIR="$1"
 
 if ! [ -e 'zfs_config.h' ]
 then
-	echo >&2
-	echo "    $0: you did not run configure, or you're not in the ZFS source directory." >&2
-	echo "    $0: run configure with --with-linux=$KERNEL_DIR and --enable-linux-builtin." >&2
-	echo >&2
+	echo "$0: you did not run configure, or you're not in the ZFS source directory."
+	echo "$0: run configure with --with-linux=$KERNEL_DIR and --enable-linux-builtin."
+
 	exit 1
-fi
+fi >&2
 
-make clean || true
+make clean ||:
 make gitrev
 
 rm -rf "$KERNEL_DIR/include/zfs" "$KERNEL_DIR/fs/zfs"
-cp --recursive include "$KERNEL_DIR/include/zfs"
-cp --recursive module "$KERNEL_DIR/fs/zfs"
+cp -R include "$KERNEL_DIR/include/zfs"
+cp -R module "$KERNEL_DIR/fs/zfs"
 cp zfs_config.h "$KERNEL_DIR/include/zfs/"
 
-cat > "$KERNEL_DIR/fs/zfs/Kconfig" <<"EOF"
+cat > "$KERNEL_DIR/fs/zfs/Kconfig" <<EOF
 config ZFS
 	tristate "ZFS filesystem support"
 	depends on EFI_PARTITION
@@ -46,22 +45,21 @@ EOF
 
 add_after()
 {
-	local FILE="$1"
-	local MARKER="$2"
-	local NEW="$3"
-	local LINE
+	FILE="$1"
+	MARKER="$2"
+	NEW="$3"
 
 	while IFS='' read -r LINE
 	do
-		echo "$LINE"
+		printf "%s\n" "$LINE"
 
-		if [ -n "$MARKER" -a "$LINE" = "$MARKER" ]
+		if [ -n "$MARKER" ] && [ "$LINE" = "$MARKER" ]
 		then
-			echo "$NEW"
+			printf "%s\n" "$NEW"
 			MARKER=''
 			if IFS='' read -r LINE
 			then
-				[ "$LINE" != "$NEW" ] && echo "$LINE"
+				[ "$LINE" != "$NEW" ] && printf "%s\n" "$LINE"
 			fi
 		fi
 	done < "$FILE" > "$FILE.new"
@@ -72,8 +70,5 @@ add_after()
 add_after "$KERNEL_DIR/fs/Kconfig" 'if BLOCK' 'source "fs/zfs/Kconfig"'
 add_after "$KERNEL_DIR/fs/Makefile" 'endif' 'obj-$(CONFIG_ZFS) += zfs/'
 
-echo >&2
-echo "    $0: done." >&2
-echo "    $0: now you can build the kernel with ZFS support." >&2
-echo "    $0: make sure you enable ZFS support (CONFIG_ZFS) before building." >&2
-echo >&2
+echo "$0: done. now you can build the kernel with ZFS support." >&2
+echo "$0: make sure you enable ZFS support (CONFIG_ZFS) before building." >&2