1 files changed, 25 insertions, 0 deletions
diff --git a/lib/spack/llnl/util/filesystem.py b/lib/spack/llnl/util/filesystem.py
index 330ee35911..4dfea7975d 100644
--- a/lib/spack/llnl/util/filesystem.py
+++ b/lib/spack/llnl/util/filesystem.py
@@ -2630,3 +2630,28 @@ def temporary_dir(
             yield tmp_dir
     finally:
         remove_directory_contents(tmp_dir)
+
+
+def filesummary(path, print_bytes=16) -> Tuple[int, bytes]:
+    """Create a small summary of the given file. Does not error
+    when file does not exist.
+
+    Args:
+        print_bytes (int): Number of bytes to print from start/end of file
+
+    Returns:
+        Tuple of size and byte string containing first n .. last n bytes.
+        Size is 0 if file cannot be read."""
+    try:
+        n = print_bytes
+        with open(path, "rb") as f:
+            size = os.fstat(f.fileno()).st_size
+            if size <= 2 * n:
+                short_contents = f.read(2 * n)
+            else:
+                short_contents = f.read(n)
+                f.seek(-n, 2)
+                short_contents += b"..." + f.read(n)
+        return size, short_contents
+    except OSError:
+        return 0, b""