From: Radoslaw Zarzynski <rzarzyns@redhat.com>
Date: Tue, 20 Jul 2021 10:32:36 +0000 (+0000)
Subject: tests/bl: verify the carriage handling in bufferlist::c_str().
X-Git-Tag: v17.1.0~891^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=refs%2Fpull%2F42417%2Fhead;p=ceph.git

tests/bl: verify the carriage handling in bufferlist::c_str().

Signed-off-by: Radoslaw Zarzynski <rzarzyns@redhat.com>
---

diff --git a/src/test/bufferlist.cc b/src/test/bufferlist.cc
index 4d830f6e97e1..4f9ebd44b92d 100644
--- a/src/test/bufferlist.cc
+++ b/src/test/bufferlist.cc
@@ -2320,6 +2320,25 @@ TEST(BufferList, c_str) {
   EXPECT_EQ(0, ::memcmp("AB", bl.c_str(), 2));
 }
 
+TEST(BufferList, c_str_carriage) {
+  // verify the c_str() optimization for carriage handling
+  buffer::ptr bp("A", 1);
+  bufferlist bl;
+  bl.append(bp);
+  bl.append('B');
+  EXPECT_EQ(2U, bl.get_num_buffers());
+  EXPECT_EQ(2U, bl.length());
+
+  // this should leave an empty bptr for carriage at the end of the bl
+  bl.splice(1, 1);
+  EXPECT_EQ(2U, bl.get_num_buffers());
+  EXPECT_EQ(1U, bl.length());
+
+  std::ignore = bl.c_str();
+  // if we have an empty bptr at the end, we don't need to rebuild
+  EXPECT_EQ(2U, bl.get_num_buffers());
+}
+
 TEST(BufferList, substr_of) {
   bufferlist bl;
   EXPECT_THROW(bl.substr_of(bl, 1, 1), buffer::end_of_buffer);