public inbox for gentoo-osx@lists.gentoo.org
 help / color / mirror / Atom feed
* [gentoo-osx] SheBang script
@ 2005-09-13 20:58 Grobian
  2005-09-14 16:06 ` Kito
  0 siblings, 1 reply; 10+ messages in thread
From: Grobian @ 2005-09-13 20:58 UTC (permalink / raw
  To: gentoo-osx

[-- Attachment #1: Type: text/plain, Size: 505 bytes --]

Ok, I didn't really know where to put it, but I wanted to share my 
efforts with some people in an early phase.  This is the result of half 
an hour script-fu hacking.  I think it might be useful with regard to 
the upcoming portage.

See introductionary comment in the attach to get an idea what it does.

It currently only generates diff -u output, but it's quite easy to "| 
patch" it, and much safer for now to see what is happening, and if that 
is desired ;)

-- 
Fabian Groffen
Gentoo for Mac OS X

[-- Attachment #2: shebang --]
[-- Type: text/plain, Size: 2300 bytes --]

#!/usr/bin/env sh

# SheBang(tm) - a Gentoo script to rape files in a given directory for
# the purpose of supporting a variable 'prefix'.
#
# Fabian Groffen <grobian at gentoo (dot] org>
# 0.1 - initial mockup (20050913)
#
# This script searches for executable script files in the given
# directory and all its sub-directories and tries to process them in
# such a way, that the actual PATH environment controls how they are
# executed.  An example would be a script file having at the first line:
#    #!/usr/bin/perl
# this will be changed into:
#    #!/usr/bin/env perl
# where the actual location of 'perl' is resolved at runtime by 'env'
# using the current PATH environment.  The location of 'env' can be set
# using the variable ENV_PATH below.

# path to the env executable
ENV_PATH="/usr/bin/env"

if [ -z $1 ];
then
	echo "$0 needs an argument: the directory to process" > /dev/stderr
	exit 1;
fi

# make a list with candidate files... well actually find 'em all and let
# file(1) tell us if it is text somehow.  Let awk do some magic to read
# the file and see if the first line starts with "#!".
CANDS=`find $1 -type f -exec file '{}' \; | grep text | cut -d: -f1 | \
awk '
{
	file = $1
	getline < file
	if ($0 ~ /^#!/) print file
	close(file)
}
'`
# we basically have only candidate files in our hands now, so we should
# continue with the script-fu to see if we can do something with the
# "#!/some/where/file" thing...
for cand in $CANDS;
do
	# first get the first line of the file without the #!
	line=`head -n1 $cand | cut -c3-`
	# then see if we know this executable thing
	command=`echo $line | cut -d' ' -f 1`
	name=`basename $command`
	case "$name" in
		sh)
			fine=1;
		;;
		bash)
			fine=1;
		;;
		perl)
			fine=1;
		;;
		awk)
			fine=1;
		;;
		*)
			# we don't know these, and maybe we shouldn't touch them
			fine=0;
		;;
	esac

	if [ $fine -eq 1 ];
	then
		# we know these, and they are fine
		awk -v name="$name" \
				-v file="$cand" \
				-v envpath="$ENV_PATH" \
				-v command="$command" '
			BEGIN {
				for (i = 1; (getline line < file) > 0; i++) {
					if (i == 1) {
						out = "#!" envpath " " name
						out = out substr($0, length(command) + 2 + 1)
						print out
					} else {
						print line
					}
				}
				close(file)
			}
		' | diff -u $cand -
	fi
done

^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2005-09-19 16:39 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2005-09-13 20:58 [gentoo-osx] SheBang script Grobian
2005-09-14 16:06 ` Kito
2005-09-14 16:33   ` Brian Harring
2005-09-14 16:42     ` Grobian
2005-09-14 16:45       ` Brian Harring
2005-09-14 16:49         ` Brian Harring
2005-09-14 16:53           ` Grobian
2005-09-14 17:03             ` Brian Harring
2005-09-14 16:51         ` Grobian
2005-09-19 16:39           ` Grobian

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox