test: add libcephfs snap.btime xattr test

Test that the new "ceph.snap.btime" xattr is present following
snapshot, and that the corresponding $secs.$nsecs value changes between
old and new snapshots.

Fixes: https://tracker.ceph.com/issues/38838
Signed-off-by: David Disseldorp <ddiss@suse.de>
(cherry picked from commit efb3ddd9a49b81f2ab23d86a5b025630f3424050)

diff --git a/src/test/libcephfs/test.cc b/src/test/libcephfs/test.cc
index e312a291b1d114878160c4c27c7384c89607c55f..78b95af801cb433267543555ceb7d7dc68d03d30 100644 (file)
--- a/src/test/libcephfs/test.cc
+++ b/src/test/libcephfs/test.cc
@@ -2185,3 +2185,67 @@ TEST(LibCephFS, OperationsOnDotDot) {
 
   ceph_shutdown(cmount);
 }
+
+TEST(LibCephFS, SnapXattrs) {
+  struct ceph_mount_info *cmount;
+  ASSERT_EQ(ceph_create(&cmount, NULL), 0);
+  ASSERT_EQ(ceph_conf_read_file(cmount, NULL), 0);
+  ASSERT_EQ(0, ceph_conf_parse_env(cmount, NULL));
+  ASSERT_EQ(ceph_mount(cmount, NULL), 0);
+
+  char test_snap_xattr_file[256];
+  char c_temp[PATH_MAX];
+  char gxattrv[128];
+  char gxattrv2[128];
+  int xbuflen = sizeof(gxattrv);
+  pid_t mypid = getpid();
+
+  sprintf(test_snap_xattr_file, "test_snap_xattr_%d", mypid);
+  int fd = ceph_open(cmount, test_snap_xattr_file, O_CREAT, 0666);
+  ASSERT_GT(fd, 0);
+  ceph_close(cmount, fd);
+
+  sprintf(c_temp, "/.snap/test_snap_xattr_snap_%d", mypid);
+  ASSERT_EQ(0, ceph_mkdir(cmount, c_temp, 0777));
+
+  int alen = ceph_getxattr(cmount, c_temp, "ceph.snap.btime", (void *)gxattrv, xbuflen);
+  // xattr value is secs.nsecs (don't assume zero-term)
+  ASSERT_LT(0, alen);
+  ASSERT_LT(alen, xbuflen);
+  gxattrv[alen] = '\0';
+  char *s = strchrnul(gxattrv, '.');
+  ASSERT_LT(s, gxattrv + alen);
+  ASSERT_EQ('.', *s);
+  *s = '\0';
+  utime_t btime = utime_t(strtoull(gxattrv, NULL, 10), strtoull(s + 1, NULL, 10));
+  *s = '.';  // restore for later strcmp
+
+  // file within the snapshot should carry the same btime
+  sprintf(c_temp, "/.snap/test_snap_xattr_snap_%d/%s", mypid, test_snap_xattr_file);
+
+  int alen2 = ceph_getxattr(cmount, c_temp, "ceph.snap.btime", (void *)gxattrv2, xbuflen);
+  ASSERT_EQ(alen, alen2);
+  ASSERT_EQ(0, strncmp(gxattrv, gxattrv2, alen));
+
+  // non-snap file shouldn't carry the xattr
+  alen = ceph_getxattr(cmount, test_snap_xattr_file, "ceph.snap.btime", (void *)gxattrv2, xbuflen);
+  ASSERT_EQ(-ENODATA, alen);
+
+  // create a second snapshot
+  sprintf(c_temp, "/.snap/test_snap_xattr_snap2_%d", mypid);
+  ASSERT_EQ(0, ceph_mkdir(cmount, c_temp, 0777));
+
+  // check that the btime for the newer snapshot is > older
+  alen = ceph_getxattr(cmount, c_temp, "ceph.snap.btime", (void *)gxattrv2, xbuflen);
+  ASSERT_LT(0, alen);
+  ASSERT_LT(alen, xbuflen);
+  gxattrv2[alen] = '\0';
+  s = strchrnul(gxattrv2, '.');
+  ASSERT_LT(s, gxattrv2 + alen);
+  ASSERT_EQ('.', *s);
+  *s = '\0';
+  utime_t new_btime = utime_t(strtoull(gxattrv2, NULL, 10), strtoull(s + 1, NULL, 10));
+  ASSERT_LT(btime, new_btime);
+
+  ceph_shutdown(cmount);
+}