X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=dgit.git;a=blobdiff_plain;f=dgit;fp=dgit;h=2a5e26b0e0dcbca60b938a18e87c6fa09371316f;hp=b8922dae0c76c9970446eb59fa4ea98deaf01420;hb=641eeadd77583420e7ad32d6a0414a24f4fc83bb;hpb=e7bf758b02322662a888d347d13243501d109b74

diff --git a/dgit b/dgit
index b8922dae..2a5e26b0 100755
--- a/dgit
+++ b/dgit
@@ -563,6 +563,23 @@ sub parsechangelog {
     return $c;
 }
 
+sub git_get_ref ($) {
+    my ($refname) = @_;
+    my $got = cmdoutput_errok @git, qw(show-ref --), $refname;
+    if (!defined $got) {
+	$?==256 or fail "git show-ref failed (status $?)";
+	printdebug "ref $refname= [show-ref exited 1]\n";
+	return '';
+    }
+    if ($got =~ m/^(\w+) \Q$refname\E$/m) {
+	printdebug "ref $refname=$1\n";
+	return $1;
+    } else {
+	printdebug "ref $refname= [no match]\n";
+	return '';
+    }
+}
+
 our %rmad;
 
 sub archive_query ($) {
@@ -983,22 +1000,13 @@ sub fetch_from_archive () {
 	progress "no version available from the archive";
     }
 
-    my $lrref_fn = ".git/".lrref();
-    if (open H, $lrref_fn) {
-	$lastpush_hash = <H>;
-	chomp $lastpush_hash;
-	die "$lrref_fn $lastpush_hash ?" unless $lastpush_hash =~ m/^\w+$/;
-    } elsif ($! == &ENOENT) {
-	$lastpush_hash = '';
-    } else {
-	die "$lrref_fn $!";
-    }
+    $lastpush_hash = git_get_ref(lrref());
     printdebug "previous reference hash=$lastpush_hash\n";
     my $hash;
     if (defined $dsc_hash) {
-	fail "missing git history even though dsc has hash -".
-	    " could not find commit $dsc_hash".
-	    " (should be in ".access_giturl()."#".rrref().")"
+	fail "missing remote git history even though dsc has hash -".
+	    " could not find ref ".lrref().
+	    " (should have been fetched from ".access_giturl()."#".rrref().")"
 	    unless $lastpush_hash;
 	$hash = $dsc_hash;
 	ensure_we_have_orig();