Add helpers to determine whether directories or files are soft links

Signed-off-by: Mateusz Grzonka <mateusz.grzonka@intel.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jes Sorensen <jes@trained-monkey.org>

2 files changed, 47 insertions, 0 deletions

diff --git a/mdadm.h b/mdadm.h
index 13f8b4cb..1674ce13 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -1777,6 +1777,8 @@ extern void set_dlm_hooks(void);
 #define MSEC_TO_NSEC(msec) ((msec) * 1000000)
 #define USEC_TO_NSEC(usec) ((usec) * 1000)
 extern void sleep_for(unsigned int sec, long nsec, bool wake_after_interrupt);
+extern bool is_directory(const char *path);
+extern bool is_file(const char *path);
 
 #define _ROUND_UP(val, base)	(((val) + (base) - 1) & ~(base - 1))
 #define ROUND_UP(val, base)	_ROUND_UP(val, (typeof(val))(base))
diff --git a/util.c b/util.c
index 8c7f3fd5..7fc881bf 100644
--- a/util.c
+++ b/util.c
@@ -2401,3 +2401,48 @@ void sleep_for(unsigned int sec, long nsec, bool wake_after_interrupt)
 		}
 	} while (!wake_after_interrupt && errno == EINTR);
 }
+
+/* is_directory() - Checks if directory provided by path is indeed a regular directory.
+ * @path: directory path to be checked
+ *
+ * Doesn't accept symlinks.
+ *
+ * Return: true if is a directory, false if not
+ */
+bool is_directory(const char *path)
+{
+	struct stat st;
+
+	if (lstat(path, &st) != 0) {
+		pr_err("%s: %s\n", strerror(errno), path);
+		return false;
+	}
+
+	if (!S_ISDIR(st.st_mode))
+		return false;
+
+	return true;
+}
+
+/*
+ * is_file() - Checks if file provided by path is indeed a regular file.
+ * @path: file path to be checked
+ *
+ * Doesn't accept symlinks.
+ *
+ * Return: true if is  a file, false if not
+ */
+bool is_file(const char *path)
+{
+	struct stat st;
+
+	if (lstat(path, &st) != 0) {
+		pr_err("%s: %s\n", strerror(errno), path);
+		return false;
+	}
+
+	if (!S_ISREG(st.st_mode))
+		return false;
+
+	return true;
+}