Merge branch 'maint'

* maint:
  fast-import: close pack before unlinking it
  pager: do not dup2 stderr if it is already redirected
  git-show: do not segfault when showing a bad tag

Author: gitster

builtin-log.c

@@ -340,7 +340,13 @@ int cmd_show(int argc, const char **argv, const char *prefix)
 					t->tag,
 					diff_get_color_opt(&rev.diffopt, DIFF_RESET));
 			ret = show_object(o->sha1, 1, &rev);
-			objects[i].item = parse_object(t->tagged->sha1);
+			if (ret)
+				break;
+			o = parse_object(t->tagged->sha1);
+			if (!o)
+				ret = error("Could not read object %s",
+					    sha1_to_hex(t->tagged->sha1));
+			objects[i].item = o;
 			i--;
 			break;
 		}

fast-import.c

@@ -983,8 +983,10 @@ static void end_packfile(void)
 
 		pack_id++;
 	}
-	else
+	else {
+		close(old_p->pack_fd);
 		unlink(old_p->pack_name);
+	}
 	free(old_p);
 
 	/* We can't carry a delta across packfiles. */

pager.c

@@ -70,7 +70,8 @@ void setup_pager(void)
 
 	/* original process continues, but writes to the pipe */
 	dup2(pager_process.in, 1);
-	dup2(pager_process.in, 2);
+	if (isatty(2))
+		dup2(pager_process.in, 2);
 	close(pager_process.in);
 
 	/* this makes sure that the parent terminates after the pager */

t/t7007-show.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+
+test_description='git show'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+	echo hello world >foo &&
+	H=$(git hash-object -w foo) &&
+	git tag -a foo-tag -m "Tags $H" $H &&
+	HH=$(expr "$H" : "\(..\)") &&
+	H38=$(expr "$H" : "..\(.*\)") &&
+	rm -f .git/objects/$HH/$H38
+'
+
+test_expect_success 'showing a tag that point at a missing object' '
+	test_must_fail git --no-pager show foo-tag
+'
+
+test_done