Adding --lzma option to make-dist

Adding --lzma option to make-dist

[Sven Joachim]

Inspired by the latest change that added the --bzip2 option to
make-dist, I did the same for --lzma and ran a short benchmark to
compare the results with the various compressors.  Here is a summary of
the results for `make-dist --snapshot' in the Emacs trunk on my
machine¹:

Option   creation time (s)  tarball size (B)  unpacking time (s)
-------  -----------------  ---------------   ------------------
(none)        30.45           39,821,789           3.49
--bzip2       84.28           31,947,657          26.34
--lzma       338.23           26,797,729           7.71

It seems that the lzma format would be a very good candidate for
distribution tarballs, if only it were more widespread; information and
downloads are available at http://www.7-zip.org/sdk.html.

Diff and Changelog entry:

--8<---------------cut here---------------start------------->8---
--- make-dist	5 Jan 2008 13:26:33 -0000	1.239
+++ make-dist	13 Jan 2008 08:35:11 -0000
@@ -86,6 +86,11 @@
       default_gzip="bzip2"
     ;;
 
+    ## Same with lzma.
+    "--lzma")
+      default_gzip="lzma"
+    ;;
+
     "--snapshot")
       clean_up=yes
       make_tar=yes
@@ -99,6 +104,7 @@
       echo "  --bzip2		use bzip2 instead of gzip"
       echo "  --clean-up	delete staging directories when done"
       echo "  --compress	use compress instead of gzip"
+      echo "  --lzma		use lzma instead of gzip"
       echo "  --newer=TIME	don't include files older than TIME"
       echo "  --no-check	don't check for bad file names etc."
       echo "  --no-update	don't recompile or do analogous things"
@@ -750,6 +756,7 @@
   case "${default_gzip}" in
     bzip2)      gzip_extension=.bz2 ;;
     compress* ) gzip_extension=.Z ;;
+    lzma)      gzip_extension=.lzma ;;
     * )         gzip_extension=.gz ;;
   esac
   echo "Creating tar file"
--8<---------------cut here---------------end--------------->8---

2008-01-13  Sven Joachim  <svenjoac@gmx.de>

	* make-dist: Add --lzma.


¹ Athlon XP 2400+ (2Ghz), 1 GB RAM