Add dm_device_has_holders fn to to check use of the device by another device.

Add dm_device_has_mounted_fs fn to check mounted filesystem on a device.

This requires sysfs directory to be correctly set via dm_set_sysfs_dir
(/sys by default). If sysfs dir is not used or it's set incorrectly,
dm_device_has_{holders,mounted_fs} will return 0!

1 files changed, 20 insertions, 0 deletions

diff --git a/libdm/libdm-file.c b/libdm/libdm-file.c
index 91fdce02..700008bc 100644
--- a/libdm/libdm-file.c
+++ b/libdm/libdm-file.c
@@ -76,6 +76,26 @@ int dm_create_dir(const char *dir)
 	return 0;
 }
 
+int dm_is_empty_dir(const char *dir)
+{
+	struct dirent *dirent;
+	DIR *d;
+
+	if (!(d = opendir(dir))) {
+		log_sys_error("opendir", dir);
+		return 0;
+	}
+
+	while ((dirent = readdir(d)))
+		if (strcmp(dirent->d_name, ".") && strcmp(dirent->d_name, ".."))
+			break;
+
+	if (closedir(d))
+		log_sys_error("closedir", dir);
+
+	return dirent ? 0 : 1;
+}
+
 int dm_fclose(FILE *stream)
 {
 	int prev_fail = ferror(stream);