cvsimport - cleanup of the multi-indexes handling

Indexes are only needed when we are about preparing to commit. Prime them
inside commit() when we have all the info we need, and remove all the
redundant index setups.

While we are at it, make sure that index handling is correct when opening
new branches, and on initial import.

Signed-off-by: Martin Langhoff <martin@catalyst.net.nz>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-cvsimport.perl

@@ -467,11 +467,6 @@ ($$)
 $orig_git_index = $ENV{GIT_INDEX_FILE} if exists $ENV{GIT_INDEX_FILE};
 
 my %index; # holds filenames of one index per branch
-$index{$opt_o} = tmpnam();
-
-$ENV{GIT_INDEX_FILE} = $index{$opt_o};
-system("git-read-tree", $opt_o);
-die "read-tree failed: $?\n" if $?;
 
 unless(-d $git_dir) {
 	system("git-init-db");
@@ -499,14 +494,6 @@ ($$)
 	$orig_branch = $last_branch;
 	$tip_at_start = `git-rev-parse --verify HEAD`;
 
-	# populate index
-	unless ($index{$last_branch}) {
-	    $index{$last_branch} = tmpnam();
-	}
-	$ENV{GIT_INDEX_FILE} = $index{$last_branch};
-	system('git-read-tree', $last_branch);
-	die "read-tree failed: $?\n" if $?;
-
 	# Get the last import timestamps
 	opendir(D,"$git_dir/refs/heads");
 	while(defined(my $head = readdir(D))) {
@@ -623,6 +610,27 @@ ()
 $ignorebranch{'#CVSPS_NO_BRANCH'} = 1;
 
 sub commit {
+	if ($branch eq $opt_o && !$index{branch} && !get_headref($branch, $git_dir)) {
+	    # looks like an initial commit
+	    # use the index primed by git-init-db
+	    $ENV{GIT_INDEX_FILE} = '.git/index';
+	    $index{$branch} = '.git/index';
+	} else {
+	    # use an index per branch to speed up
+	    # imports of projects with many branches
+	    unless ($index{$branch}) {
+		$index{$branch} = tmpnam();
+		$ENV{GIT_INDEX_FILE} = $index{$branch};
+		if ($ancestor) {
+		    system("git-read-tree", $ancestor);
+		} else {
+		    system("git-read-tree", $branch);
+		}
+		die "read-tree failed: $?\n" if $?;
+	    }
+	}
+        $ENV{GIT_INDEX_FILE} = $index{$branch};
+
 	update_index(@old, @new);
 	@old = @new = ();
 	my $tree = write_tree();
@@ -811,30 +819,6 @@ sub commit {
 			close(H)
 				or die "Could not write branch $branch: $!";
 		}
-		if(($ancestor || $branch) ne $last_branch) {
-			print "Switching from $last_branch to $branch\n" if $opt_v;
-			unless ($index{$branch}) {
-			    $index{$branch} = tmpnam();
-			    $ENV{GIT_INDEX_FILE} = $index{$branch};
-			    system("git-read-tree", $branch);
-			    die "read-tree failed: $?\n" if $?;
-			}
-			# just in case
-			$ENV{GIT_INDEX_FILE} = $index{$branch};
-			if ($ancestor) {
-			    print "have ancestor $ancestor" if $opt_v;
-			    system("git-read-tree", $ancestor);
-			    die "read-tree failed: $?\n" if $?;
-			}
-		} else {
-			# just in case
-			unless ($index{$branch}) {
-			    $index{$branch} = tmpnam();
-			    $ENV{GIT_INDEX_FILE} = $index{$branch};
-			    system("git-read-tree", $branch);
-			    die "read-tree failed: $?\n" if $?;
-			}
-		}
 		$last_branch = $branch if $branch ne $last_branch;
 		$state = 9;
 	} elsif($state == 8) {
@@ -898,7 +882,9 @@ sub commit {
 commit() if $branch and $state != 11;
 
 foreach my $git_index (values %index) {
-    unlink($git_index);
+    if ($git_index ne '.git/index') {
+	unlink($git_index);
+    }
 }
 
 if (defined $orig_git_index) {