From 020f57cb746ad7b5ed9a0fafa0a80b427cf6f3ae Mon Sep 17 00:00:00 2001
From: Christoph Klaffl <christoph@phreaker.eu>
Date: Mon, 30 Jul 2018 09:43:03 +0200
Subject: [PATCH] check for error while listing snapshots/bookmarks as this can
 be dangerous with force-delete

---
 syncoid | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/syncoid b/syncoid
index a6500bb..26307ba 100755
--- a/syncoid
+++ b/syncoid
@@ -1114,7 +1114,7 @@ sub getsnaps() {
 	if ($debug) { print "DEBUG: getting list of snapshots on $fs using $getsnapcmd...\n"; }
 	open FH, $getsnapcmd;
 	my @rawsnaps = <FH>;
-	close FH;
+	close FH or die "CRITICAL ERROR: snapshots couldn't be listed for $fs (exit code $?)";
 
 	# this is a little obnoxious. get guid,creation returns guid,creation on two separate lines
 	# as though each were an entirely separate get command.
@@ -1158,11 +1158,21 @@ sub getbookmarks() {
 		$fsescaped = escapeshellparam($fsescaped);
 	}
 
-	my $getbookmarkcmd = "$rhost $mysudocmd $zfscmd get -Hpd 1 -t bookmark guid,creation $fsescaped |";
+	my $error = 0;
+	my $getbookmarkcmd = "$rhost $mysudocmd $zfscmd get -Hpd 1 -t bookmark guid,creation $fsescaped 2>&1 |";
 	if ($debug) { print "DEBUG: getting list of bookmarks on $fs using $getbookmarkcmd...\n"; }
 	open FH, $getbookmarkcmd;
 	my @rawbookmarks = <FH>;
-	close FH;
+	close FH or $error = 1;
+
+	if ($error == 1) {
+		if ($rawbookmarks[0] =~ /invalid type/) {
+			# no support for zfs bookmarks, return empty hash
+			return %bookmarks;
+		}
+
+		die "CRITICAL ERROR: bookmarks couldn't be listed for $fs (exit code $?)";
+	}
 
 	# this is a little obnoxious. get guid,creation returns guid,creation on two separate lines
 	# as though each were an entirely separate get command.