Dir#chdir keeps GVL if passed block

On further examination, Dir.chdir with a block from multiple
threads is thread-unsafe given our use of the chdir_blocking and
chdir_thread global variables.

This bug was only introduced in r60583 so not part of any stable
release.

Dir.chdir without a block can still make senses in a MT context
as only one thread could be cwd-sensitive and other threads do
not care which directory they're in.

* dir.c (dir_chdir): keep GVL here
  (dir_s_chdir): release GVL if no block given

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61091 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 8 insertions, 6 deletions

diff --git a/dir.c b/dir.c
index 378396a9f7..be20c43ce1 100644
--- a/dir.c
+++ b/dir.c
@@ -1002,11 +1002,7 @@ nogvl_chdir(void *ptr)
 static void
 dir_chdir(VALUE path)
 {
-    int r;
-    char *p = RSTRING_PTR(path);
-
-    r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_chdir, p, RUBY_UBF_IO, 0);
-    if (r < 0)
+    if (chdir(RSTRING_PTR(path)) < 0)
 	rb_sys_fail_path(path);
 }
 
@@ -1111,7 +1107,13 @@ dir_s_chdir(int argc, VALUE *argv, VALUE obj)
 	args.done = FALSE;
 	return rb_ensure(chdir_yield, (VALUE)&args, chdir_restore, (VALUE)&args);
     }
-    dir_chdir(path);
+    else {
+	char *p = RSTRING_PTR(path);
+	int r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_chdir, p,
+							RUBY_UBF_IO, 0);
+	if (r < 0)
+	    rb_sys_fail_path(path);
+    }
 
     return INT2FIX(0);
 }