On Sat, Jan 16, 2021 at 06:56:18PM +0200, Amir Goldstein wrote:
> For overlayfs tests we need to be able to setflags on existing
> (lower) files.
>
> t_immutable -C test_dir
>
> Creates the test area and sets flags, but it also allows setting flags
> on an existing test area.
>
> t_immutable -R test_dir
>
> Removes the flags from existing test area, but does not remove the files
> in the test area.
>
> To setup a test area with file without flags, need to run the -C and -R
> commands.
>
> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
> src/t_immutable.c | 30 ++++++++++++++++++++++++------
> 1 file changed, 24 insertions(+), 6 deletions(-)
>
> diff --git a/src/t_immutable.c b/src/t_immutable.c
> index b6a76af0..a2e6796d 100644
> --- a/src/t_immutable.c
> +++ b/src/t_immutable.c
> @@ -1898,6 +1898,8 @@ static int check_test_area(const char *dir)
> return 0;
> }
>
> +static int allow_existing;
> +
> static int create_dir(char **ppath, const char *fmt, const char *dir)
> {
> const char *path;
> @@ -1908,6 +1910,9 @@ static int create_dir(char **ppath, const char *fmt, const char *dir)
> }
> path = *ppath;
> if (stat(path, &st) == 0) {
> + if (allow_existing && S_ISDIR(st.st_mode)) {
> + return 0;
> + }
> fprintf(stderr, "%s: Test area directory %s must not exist for test area creation.\n",
> __progname, path);
> return 1;
> @@ -1921,6 +1926,7 @@ static int create_dir(char **ppath, const char *fmt, const char *dir)
>
> static int create_file(char **ppath, const char *fmt, const char *dir)
> {
> + int flags = O_WRONLY|O_CREAT | (allow_existing ? 0 : O_EXCL);
> const char *path;
> int fd;
>
> @@ -1928,7 +1934,7 @@ static int create_file(char **ppath, const char *fmt, const char *dir)
> return -1;
> }
> path = *ppath;
> - if ((fd = open(path, O_WRONLY|O_CREAT|O_EXCL, 0666)) == -1) {
> + if ((fd = open(path, flags, 0666)) == -1) {
> fprintf(stderr, "%s: error creating file %s: %s\n", __progname, path, strerror(errno));
> return -1;
> }
> @@ -1937,13 +1943,15 @@ static int create_file(char **ppath, const char *fmt, const char *dir)
>
> static int create_xattrs(int fd)
> {
> - if (fsetxattr(fd, "trusted.test", "readonly", strlen("readonly"), XATTR_CREATE) != 0) {
> + int flags = allow_existing ? 0 : XATTR_CREATE;
> +
> + if (fsetxattr(fd, "trusted.test", "readonly", strlen("readonly"), flags) != 0) {
> if (errno != EOPNOTSUPP) {
> perror("setxattr");
> return 1;
> }
> }
> - if (fsetxattr(fd, "user.test", "readonly", strlen("readonly"), XATTR_CREATE) != 0) {
> + if (fsetxattr(fd, "user.test", "readonly", strlen("readonly"), flags) != 0) {
> if (errno != EOPNOTSUPP) {
> perror("setxattr");
> return 1;
> @@ -2214,6 +2222,10 @@ static int remove_test_area(const char *dir)
> return 1;
> }
>
> + if (allow_existing) {
> + return 0;
> + }
> +
> pid = fork();
> if (!pid) {
> execl("/bin/rm", "rm", "-rf", dir, NULL);
> @@ -2236,7 +2248,7 @@ int main(int argc, char **argv)
> /* this arg parsing is gross, but who cares, its a test program */
>
> if (argc < 2) {
> - fprintf(stderr, "usage: t_immutable [-C|-c|-r] test_area_dir\n");
> + fprintf(stderr, "usage: t_immutable [-C|-c|-R|-r] test_area_dir\n");
> return 1;
> }
>
> @@ -2246,18 +2258,24 @@ int main(int argc, char **argv)
> /* Prepare test area without running tests */
> create = 1;
> runtest = 0;
> + /* With existing test area, only setflags */
> + allow_existing = 1;
> } else if (!strcmp(argv[1], "-r")) {
> remove = 1;
> + } else if (!strcmp(argv[1], "-R")) {
> + /* Cleanup flags on test area but leave the files */
> + remove = 1;
> + allow_existing = 1;
> }
>
> if (argc != 2 + (create | remove)) {
> - fprintf(stderr, "usage: t_immutable [-C|-c|-r] test_area_dir\n");
> + fprintf(stderr, "usage: t_immutable [-C|-c|-R|-r] test_area_dir\n");
> return 1;
> }
>
> if (create) {
> ret = create_test_area(argv[argc-1]);
> - if (ret || !runtest) {
> + if (ret || allow_existing) {
With this change, compiler warns about 'runtest' is set but not used,
and 'allow_existing' now indicates '!runtest' implicitly, which seems
subtle. I think it's better to keep 'runtest' as the indicator to
actually run the test?
Thanks,
Eryu
> return ret;
> }
> } else if (remove) {
> --
> 2.25.1
