From: Stas Maximov <smaximov@yahoo.com>
Date: Sun, 24 Jun 2007 23:10:42 GMT
Subject: Re: [PATCH] git-svnimport: added explicit merge graph option -G
Message-ID: <437777.72821.qm@web43141.mail.sp1.yahoo.com>

Junio,

Below is what I got with 

git-format-patch -p -M -s  --stdout origin

I hope this is acceptable. I checked, I do not have a MUA which preserves whitespaces such that the result is suitable for applying the patch. So I am pasting the patch below for discussion and also attaching to be suitable for applying.

Stas.

>From fd83a4e003802b6cb4dc8a2d058310f235f65e17 Mon Sep 17 00:00:00 2001
From: Stas Maximov <smaximov@yahoo.com>
Date: Sat, 23 Jun 2007 09:06:30 -0700
Subject: [PATCH] git-svnimport: added explicit merge graph option -G

Allows explicit merge graph information to be provided. Each line
of merge graph file must contain a pair of SVN revision numbers
separated by space. The first number is child (merged to) SVN rev
number and the second is the parent (merged from) SVN rev number.
Comments can be started with '#' and continue to the end of line.
Empty and space-only lines are allowed and will be ignored.

Signed-off-by: Stas Maximov <smaximov@yahoo.com>

diff --git a/Documentation/git-svnimport.txt b/Documentation/git-svnimport.txt
old mode 100644
new mode 100755
index e97d15e..c902b64
--- a/Documentation/git-svnimport.txt
+++ b/Documentation/git-svnimport.txt
@@ -13,7 +13,8 @@ SYNOPSIS
 'git-svnimport' [ -o <branch-for-HEAD> ] [ -h ] [ -v ] [ -d | -D ]
         [ -C <GIT_repository> ] [ -i ] [ -u ] [-l limit_rev]
         [ -b branch_subdir ] [ -T trunk_subdir ] [ -t tag_subdir ]
-        [ -s start_chg ] [ -m ] [ -r ] [ -M regex ]
+        [ -s start_chg ] [ -r ]
+        [ -m ] [ -M regex ] [-G merge_graph_file ]
         [ -I <ignorefile_name> ] [ -A <author_file> ]
         [ -R <repack_each_revs>] [ -P <path_from_trunk> ]
         <SVN_repository_URL> [ <path> ]
@@ -102,6 +103,14 @@ repository without -A.
     regex. It can be used with -m to also see the default regexes.
     You must escape forward slashes.
 
+-G <merge_graph_file>::
+    Allows explicit merge graph information to be provided. Each line
+    of merge graph file must contain a pair of SVN revision numbers
+    separated by space. The first number is child (merged to) SVN rev
+    number and the second is the parent (merged from) SVN rev number.
+    Comments can be started with '#' and continue to the end of line.
+    Empty and space-only lines are allowed and will be ignored.
+
 -l <max_rev>::
     Specify a maximum revision number to pull.
 +
diff --git a/git-svnimport.perl b/git-svnimport.perl
index f459762..113b252 100755
--- a/git-svnimport.perl
+++ b/git-svnimport.perl
@@ -32,7 +32,7 @@ $ENV{'TZ'}="UTC";
 
 our($opt_h,$opt_o,$opt_v,$opt_u,$opt_C,$opt_i,$opt_m,$opt_M,$opt_t,$opt_T,
     $opt_b,$opt_r,$opt_I,$opt_A,$opt_s,$opt_l,$opt_d,$opt_D,$opt_S,$opt_F,
-    $opt_P,$opt_R);
+    $opt_P,$opt_R,$opt_G);
 
 sub usage() {
     print STDERR <<END;
@@ -40,12 +40,13 @@ Usage: ${\basename $0}     # fetch/update GIT from SVN
        [-o branch-for-HEAD] [-h] [-v] [-l max_rev] [-R repack_each_revs]
        [-C GIT_repository] [-t tagname] [-T trunkname] [-b branchname]
        [-d|-D] [-i] [-u] [-r] [-I ignorefilename] [-s start_chg]
-       [-m] [-M regex] [-A author_file] [-S] [-F] [-P project_name] [SVN_URL]
+       [-m] [-M regex] [-G merge_graph_file] [-A author_file]
+       [-S] [-F] [-P project_name] [SVN_URL]
 END
     exit(1);
 }
 
-getopts("A:b:C:dDFhiI:l:mM:o:rs:t:T:SP:R:uv") or usage();
+getopts("A:b:C:dDFhiI:l:mM:G:o:rs:t:T:SP:R:uv") or usage();
 usage if $opt_h;
 
 my $tag_name = $opt_t || "tags";
@@ -80,6 +81,39 @@ if ($opt_M) {
     unshift (@mergerx, qr/$opt_M/);
 }
 
+
+# merge_graph will be used for finding all parent SVN revisions for a given SVN
+# revision. It will be implemented as a hash of hashes. First level hash will
+# be keyed with the child SVN rev and contain a hash keyed with the parent SVN
+# revisions. Values of the second level hash are not important (1 will be
+# used). The keys will be used to store the parent revs for uniqueness.
+our %merge_graph;
+
+
+# read-in the explicit merge graph specified with -G option
+if ($opt_G) {
+    open(F,"cat $opt_G | sed -e 's/#.*\$//' -e '/^\$/d' |") or
+        die("Can not open $opt_G");
+    while(<F>) {
+        chomp;
+        die "ERROR: invalid line in $opt_G: $_" unless /^\s*(\d+)\s+(\d+)\s*$/;
+        # $merge_graph{child_rev}{parent_rev} = 1;
+        $merge_graph{$1}{$2} = 1;
+    }
+    close(F);
+}
+
+
+# Given an SVN revision (string), finds all its parent SVN revisions in the
+# merge graph.
+sub merge_graph_get_parents($)
+{
+    my $child_svnrev = shift;
+    my @parents = keys(%{$merge_graph{$child_svnrev}});
+    return @parents;
+}
+
+
 # Absolutize filename now, since we will have chdir'ed by the time we
 # get around to opening it.
 $opt_A = File::Spec->rel2abs($opt_A) if $opt_A;
@@ -356,6 +390,24 @@ if ($opt_A) {
 
 open BRANCHES,">>", "$git_dir/svn2git";
 
+
+# Given an SVN revision (string), returns all corresponding GIT revisions.
+#
+# Note that it is possible that one SVN revision needs to be split into two or
+# more GIT commits (revision). For example, this will happen if SVN user
+# commits two branches at once.
+sub svnrev_to_gitrevs($)
+{
+    my $svnrev = shift;
+    my @gitrevs;
+    for my $b (keys(%branches)) {
+        push (@gitrevs, $branches{$b}{$svnrev})
+            if defined($branches{$b}{$svnrev});
+    }
+    return @gitrevs;
+}
+
+
 sub node_kind($$) {
     my ($svnpath, $revision) = @_;
     my $pool=SVN::Pool->new;
@@ -815,6 +867,19 @@ sub commit {
                     }
                 }
             }
+
+            # add parents from explicit merge graph (-G)
+            {
+                my @svnpars = merge_graph_get_parents($revision);
+                foreach my $svnp (@svnpars) {
+                    my @gitpars = svnrev_to_gitrevs($svnp);
+                    foreach my $gitp (@gitpars) {
+                        push (@parents, $gitp);
+                        #print OUT "MG: $svnp -merge-> $revision\n";
+                    }
+                }
+            }
+
             my %seen_parents = ();
             my @unique_parents = grep { ! $seen_parents{$_} ++ } @parents;
             foreach my $bparent (@unique_parents) {
-- 
1.5.1.3


>From 7008a13f1fe00fdbd90be6a12ad1197dceedaebb Mon Sep 17 00:00:00 2001
From: Stas Maximov <smaximov@yahoo.com>
Date: Sun, 24 Jun 2007 14:23:29 -0700
Subject: [PATCH] Fixed permissions of Documentation/git-svnimport.txt


Signed-off-by: Stas Maximov <smaximov@yahoo.com>

diff --git a/Documentation/git-svnimport.txt b/Documentation/git-svnimport.txt
old mode 100755
new mode 100644
-- 
1.5.1.3





----- Original Message ----
From: Junio C Hamano <gitster@pobox.com>
To: Stas Maximov <smaximov@yahoo.com>
Cc: git@vger.kernel.org; Peter Baumann <waste.manager@gmx.de>
Sent: Sunday, June 24, 2007 3:17:05 PM
Subject: Re: [PATCH] git-svnimport: added explicit merge graph option -G

Stas Maximov <smaximov@yahoo.com> writes:

> Attached are two patches:
>
> 1. resubmission of the original patch with proper sign-off; and 
> 2. patch with permissions fix (thanks to Alex Reisen for pointing out);

As you are assuming that the original patch was rejected (by
resending that as the first one here), I do not think these
changes should be in two separate commits.  Please redo them as
a single patch.

Also please do not "Attach".  When you have N patches to send,
send N e-mail messages, numbered from [PATCH 1/N] to [PATCH
N/N], each with one patch in the message itself.

Please see Documentation/SubmittingPatches.