merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 15 insertions, 11 deletions

diff --git a/third_party/git/git-cvsexportcommit.perl b/third_party/git/git-cvsexportcommit.perl
index fc00d5946a..289d4bc684 100755
--- a/third_party/git/git-cvsexportcommit.perl
+++ b/third_party/git/git-cvsexportcommit.perl
@@ -22,11 +22,15 @@ die "Need at least one commit identifier!" unless @ARGV;
 my $repo = Git->repository();
 $opt_w = $repo->config('cvsexportcommit.cvsdir') unless defined $opt_w;
 
+my $tmpdir = File::Temp::tempdir(CLEANUP => 1);
+my $hash_algo = $repo->config('extensions.objectformat') || 'sha1';
+my $hexsz = $hash_algo eq 'sha256' ? 64 : 40;
+
 if ($opt_w || $opt_W) {
 	# Remember where GIT_DIR is before changing to CVS checkout
 	unless ($ENV{GIT_DIR}) {
 		# No GIT_DIR set. Figure it out for ourselves
-		my $gd =`git-rev-parse --git-dir`;
+		my $gd =`git rev-parse --git-dir`;
 		chomp($gd);
 		$ENV{GIT_DIR} = $gd;
 	}
@@ -62,7 +66,7 @@ if ($opt_d) {
 # resolve target commit
 my $commit;
 $commit = pop @ARGV;
-$commit = safe_pipe_capture('git-rev-parse', '--verify', "$commit^0");
+$commit = safe_pipe_capture('git', 'rev-parse', '--verify', "$commit^0");
 chomp $commit;
 if ($?) {
     die "The commit reference $commit did not resolve!";
@@ -72,7 +76,7 @@ if ($?) {
 my $parent;
 if (@ARGV) {
     $parent = pop @ARGV;
-    $parent =  safe_pipe_capture('git-rev-parse', '--verify', "$parent^0");
+    $parent =  safe_pipe_capture('git', 'rev-parse', '--verify', "$parent^0");
     chomp $parent;
     if ($?) {
 	die "The parent reference did not resolve!";
@@ -80,7 +84,7 @@ if (@ARGV) {
 }
 
 # find parents from the commit itself
-my @commit  = safe_pipe_capture('git-cat-file', 'commit', $commit);
+my @commit  = safe_pipe_capture('git', 'cat-file', 'commit', $commit);
 my @parents;
 my $committer;
 my $author;
@@ -96,7 +100,7 @@ foreach my $line (@commit) {
     }
 
     if ($stage eq 'headers') {
-	if ($line =~ m/^parent (\w{40})$/) { # found a parent
+	if ($line =~ m/^parent ([0-9a-f]{$hexsz})$/) { # found a parent
 	    push @parents, $1;
 	} elsif ($line =~ m/^author (.+) \d+ [-+]\d+$/) {
 	    $author = $1;
@@ -111,7 +115,7 @@ foreach my $line (@commit) {
     }
 }
 
-my $noparent = "0000000000000000000000000000000000000000";
+my $noparent = "0" x $hexsz;
 if ($parent) {
     my $found;
     # double check that it's a valid parent
@@ -158,9 +162,9 @@ if ($opt_a) {
 close MSG;
 
 if ($parent eq $noparent) {
-    `git-diff-tree --binary -p --root $commit >.cvsexportcommit.diff`;# || die "Cannot diff";
+    `git diff-tree --binary -p --root $commit >.cvsexportcommit.diff`;# || die "Cannot diff";
 } else {
-    `git-diff-tree --binary -p $parent $commit >.cvsexportcommit.diff`;# || die "Cannot diff";
+    `git diff-tree --binary -p $parent $commit >.cvsexportcommit.diff`;# || die "Cannot diff";
 }
 
 ## apply non-binary changes
@@ -174,7 +178,7 @@ my $context = $opt_p ? '' : '-C1';
 print "Checking if patch will apply\n";
 
 my @stat;
-open APPLY, "GIT_DIR= git-apply $context --summary --numstat<.cvsexportcommit.diff|" || die "cannot patch";
+open APPLY, "GIT_INDEX_FILE=$tmpdir/index git apply $context --summary --numstat<.cvsexportcommit.diff|" || die "cannot patch";
 @stat=<APPLY>;
 close APPLY || die "Cannot patch";
 my (@bfiles,@files,@afiles,@dfiles);
@@ -329,7 +333,7 @@ print "Applying\n";
 if ($opt_W) {
     system("git checkout -q $commit^0") && die "cannot patch";
 } else {
-    `GIT_DIR= git-apply $context --summary --numstat --apply <.cvsexportcommit.diff` || die "cannot patch";
+    `GIT_INDEX_FILE=$tmpdir/index git apply $context --summary --numstat --apply <.cvsexportcommit.diff` || die "cannot patch";
 }
 
 print "Patch applied successfully. Adding new files and directories to CVS\n";
@@ -407,7 +411,7 @@ unlink(".cvsexportcommit.diff");
 
 if ($opt_W) {
     system("git checkout $go_back_to") && die "cannot move back to $go_back_to";
-    if (!($go_back_to =~ /^[0-9a-fA-F]{40}$/)) {
+    if (!($go_back_to =~ /^[0-9a-fA-F]{$hexsz}$/)) {
 	system("git symbolic-ref HEAD $go_back_to") &&
 	    die "cannot move back to $go_back_to";
     }