git-archimport: allow remapping branch names

This patch adds support to archimport for remapping the branch
names to match those used in git more closely.  This is useful
for projects that migrate to git (as opposed to users that want
to use git on Arch-based projects).  For example, one can choose
an Arch branch name and call it "master".

The new command-line syntax works even if there is a colon in
a branch name, since only the part after the last colon is taken
to be the git name (git does not allow colons in branch names).

The new feature is implemented so that archives rotated every
year can also be remapped into a single git archive.

Signed-off-by: Paolo Bonzini  <bonzini@gnu.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 64 insertions, 22 deletions

diff --git a/git-archimport.perl b/git-archimport.perl
index 0fcb156d1..c1e7c1ddc 100755
--- a/git-archimport.perl
+++ b/git-archimport.perl
@@ -89,7 +89,11 @@ usage if $opt_h;
 # values associated with keys:
 #   =1 - Arch version / git 'branch' detected via abrowse on a limit
 #   >1 - Arch version / git 'branch' of an auxiliary branch we've merged
-my %arch_branches = map { $_ => 1 } @ARGV;
+my %arch_branches = map { my $branch = $_; $branch =~ s/:[^:]*$//; $branch => 1 } @ARGV;
+
+# $branch_name_map:
+# maps arch branches to git branch names
+my %branch_name_map = map { m/^(.*):([^:]*)$/; $1 => $2 } grep { m/:/ } @ARGV;
 
 $ENV{'TMPDIR'} = $opt_t if $opt_t; # $ENV{TMPDIR} will affect tempdir() calls:
 my $tmp = tempdir('git-archimport-XXXXXX', TMPDIR => 1, CLEANUP => 1);
@@ -104,6 +108,7 @@ unless (-d $git_dir) { # initial import needs empty directory
     closedir DIR
 }
 
+my $default_archive;		# default Arch archive
 my %reachable = ();             # Arch repositories we can access
 my %unreachable = ();           # Arch repositories we can't access :<
 my @psets  = ();                # the collection
@@ -303,7 +308,34 @@ sub old_style_branchname {
     return $ret;
 }
 
-*git_branchname = $opt_o ? *old_style_branchname : *tree_dirname;
+*git_default_branchname = $opt_o ? *old_style_branchname : *tree_dirname;
+
+# retrieve default archive, since $branch_name_map keys might not include it
+sub get_default_archive {
+    if (!defined $default_archive) {
+        $default_archive = safe_pipe_capture($TLA,'my-default-archive');
+        chomp $default_archive;
+    }
+    return $default_archive;
+}
+
+sub git_branchname {
+    my $revision = shift;
+    my $name = extract_versionname($revision);
+
+    if (exists $branch_name_map{$name}) {
+	return $branch_name_map{$name};
+
+    } elsif ($name =~ m#^([^/]*)/(.*)$#
+	     && $1 eq get_default_archive()
+	     && exists $branch_name_map{$2}) {
+	# the names given in the command-line lacked the archive.
+	return $branch_name_map{$2};
+
+    } else {
+	return git_default_branchname($revision);
+    }
+}
 
 sub process_patchset_accurate {
     my $ps = shift;
@@ -333,19 +365,23 @@ sub process_patchset_accurate {
         if ($ps->{tag} && (my $branchpoint = eval { ptag($ps->{tag}) })) {
             
             # find where we are supposed to branch from
-            system('git-checkout','-f','-b',$ps->{branch},
-                            $branchpoint) == 0 or die "$! $?\n";
-            
+	    if (! -e "$git_dir/refs/heads/$ps->{branch}") {
+		system('git-branch',$ps->{branch},$branchpoint) == 0 or die "$! $?\n";
+
+		# We trust Arch with the fact that this is just a tag,
+		# and it does not affect the state of the tree, so
+		# we just tag and move on.  If the user really wants us
+		# to consolidate more branches into one, don't tag because
+		# the tag name would be already taken.
+		tag($ps->{id}, $branchpoint);
+		ptag($ps->{id}, $branchpoint);
+		print " * Tagged $ps->{id} at $branchpoint\n";
+	    }
+	    system('git-checkout','-f',$ps->{branch}) == 0 or die "$! $?\n";
+
             # remove any old stuff that got leftover:
             my $rm = safe_pipe_capture('git-ls-files','--others','-z');
             rmtree(split(/\0/,$rm)) if $rm;
-
-            # If we trust Arch with the fact that this is just 
-            # a tag, and it does not affect the state of the tree
-            # then we just tag and move on
-            tag($ps->{id}, $branchpoint);
-            ptag($ps->{id}, $branchpoint);
-            print " * Tagged $ps->{id} at $branchpoint\n";
             return 0;
         } else {
             warn "Tagging from unknown id unsupported\n" if $ps->{tag};
@@ -385,14 +421,19 @@ sub process_patchset_fast {
                 unless $branchpoint;
             
             # find where we are supposed to branch from
-            system('git-checkout','-b',$ps->{branch},$branchpoint);
-
-            # If we trust Arch with the fact that this is just 
-            # a tag, and it does not affect the state of the tree
-            # then we just tag and move on
-            tag($ps->{id}, $branchpoint);
-            ptag($ps->{id}, $branchpoint);
-            print " * Tagged $ps->{id} at $branchpoint\n";
+	    if (! -e "$git_dir/refs/heads/$ps->{branch}") {
+		system('git-branch',$ps->{branch},$branchpoint) == 0 or die "$! $?\n";
+
+		# We trust Arch with the fact that this is just a tag,
+		# and it does not affect the state of the tree, so
+		# we just tag and move on.  If the user really wants us
+		# to consolidate more branches into one, don't tag because
+		# the tag name would be already taken.
+		tag($ps->{id}, $branchpoint);
+		ptag($ps->{id}, $branchpoint);
+		print " * Tagged $ps->{id} at $branchpoint\n";
+            }
+            system('git-checkout',$ps->{branch}) == 0 or die "$! $?\n";
             return 0;
         } 
         die $! if $?;
@@ -830,8 +871,9 @@ sub tag {
     if ($opt_o) {
         $tag =~ s|/|--|g;
     } else {
-        # don't use subdirs for tags yet, it could screw up other porcelains
-        $tag =~ s|/|,|g;
+	my $patchname = $tag;
+	$patchname =~ s/.*--//;
+        $tag = git_branchname ($tag) . '--' . $patchname;
     }
     
     if ($commit) {