New option: --mountpoint.

[dss.git] / dss.c

diff --git a/dss.c b/dss.c
index 3e626ab0113b1890277da115ea6c735dbdb690d7..3d234ffb68851ddbb7996df59a8bdd31eb97c529 100644 (file)
--- a/dss.c
+++ b/dss.c
@@ -1053,17 +1053,36 @@ static int handle_sigchld(void)
        return -E_BUG;
 }
 
+/* also checks if . is a mountpoint, if --mountpoint was given */
 static int change_to_dest_dir(void)
 {
        int ret;
        const char *dd = OPT_STRING_VAL(DSS, DEST_DIR);
+       struct stat dot, dotdot;
 
        DSS_INFO_LOG(("changing cwd to %s\n", dd));
-       if (chdir(dd) >= 0)
-               return 1;
-       ret = -ERRNO_TO_DSS_ERROR(errno);
-       DSS_ERROR_LOG(("could not change cwd to %s\n", dd));
-       return ret;
+       if (chdir(dd) < 0) {
+               ret = -ERRNO_TO_DSS_ERROR(errno);
+               DSS_ERROR_LOG(("could not change cwd to %s\n", dd));
+               return ret;
+       }
+       if (!OPT_GIVEN(DSS, MOUNTPOINT))
+               return 0;
+       if (stat(".", &dot) < 0) {
+               ret = -ERRNO_TO_DSS_ERROR(errno);
+               DSS_ERROR_LOG(("could not stat .\n"));
+               return ret;
+       }
+       if (stat("..", &dotdot) < 0) {
+               ret = -ERRNO_TO_DSS_ERROR(errno);
+               DSS_ERROR_LOG(("could not stat ..\n"));
+               return ret;
+       }
+       if (dot.st_dev == dotdot.st_dev && dot.st_ino != dotdot.st_ino) {
+               DSS_ERROR_LOG(("mountpoint check failed for %s\n", dd));
+               return -E_MOUNTPOINT;
+       }
+       return 1;
 }
 
 static int check_config(const struct lls_command *cmd)