add a simple utility to Porting/ which knows how to generate .patch files

diff --git a/Porting/make_dot_patch.pl b/Porting/make_dot_patch.pl
new file mode 100755 (executable)
index 0000000..cf545ac
--- /dev/null
+++ b/Porting/make_dot_patch.pl
@@ -0,0 +1,46 @@
+use strict;
+use warnings;
+
+# This is a quickie script which I wrote to generate the .patch file for
+# an arbitrary commit. It takes on sha1 as an argument, or saving that
+# uses the sha1 associated to HEAD.
+# It tries to find which of our primary branches the sha1 can be found on,
+# and then prints to standard out something similar to what our rsync feed
+# would produce for that situation. The main difference being, in that case
+# we KNOW what branch we are on, and in this one we dont, and in that case
+# the $tstamp field holds the time the snapshot was generated (so that multiple
+# fetches will always have an increasing tstamp field), however in this case
+# we use the commit date of the sha1.
+#
+# This is more or less intended to be used as a utility to generated .patch
+# files for other processes, like gitweb and snapshots.
+#
+# The script assumes it is being run from a git WD.
+#
+# Yves
+
+use POSIX qw(strftime);
+sub isotime { strftime "%Y-%m-%d.%H:%M:%S",gmtime(shift||time) }
+
+my $sha1= shift || `git rev-parse HEAD`;
+chomp($sha1);
+my @branches=(
+          'origin/blead',
+          'origin/maint-5.10',
+          'origin/maint-5.8',
+          'origin/maint-5.8-dor',
+          'origin/maint-5.6',
+          'origin/maint-5.005',
+          'origin/maint-5.004',
+);
+my $branch;
+foreach my $b (@branches) {
+    $branch= $b and last 
+        if `git log --pretty='format:%H' $b | grep $sha1`;
+}
+
+$branch ||= "unknown-branch";
+my $tstamp= isotime(`git log -1 --pretty="format:%ct" $sha1`);
+chomp(my $describe= `git describe`);
+print join(" ", $branch, $tstamp, $sha1, $describe) . "\n";
+