sys/vfs_util: add vfs_file_exists()

sys/include/vfs_util.h

@@ -20,6 +20,9 @@
 #ifndef VFS_UTIL_H
 #define VFS_UTIL_H
 
+#include <stdbool.h>
+#include <stddef.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -115,6 +118,15 @@ int vfs_file_sha256(const char* file, void *digest,
  */
 int vfs_is_dir(const char *path);
 
+/**
+ @brief Checks if @p path is a file and can be read.
+ *
+ * @param[in]   path        Path to check
+ *
+ * @return true if the file exists, false otherwise
+ */
+bool vfs_file_exists(const char *path);
+
 /**
  * @brief    Behaves like `rm -r @p root`.
  *

sys/vfs_util/vfs_util.c

@@ -171,6 +171,17 @@ int vfs_is_dir(const char *path)
     return ((stat.st_mode & S_IFMT) == S_IFDIR);
 }
 
+bool vfs_file_exists(const char *path)
+{
+    int res = vfs_open(path, O_RDONLY, 0);
+    if (res < 0) {
+        return false;
+    }
+
+    vfs_close(res);
+    return true;
+}
+
 /**
  * @brief   Removes additional "/" slashes from @p path
  *