Update _utils.py

Add sanitation for Windows legacy devices

yt_dlp/utils/_utils.py

@@ -167,6 +167,18 @@ def IDENTITY(x):
 
 NUMBER_RE = r'\d+(?:\.\d+)?'
 
+WINDOWS_RESERVED_NAMES_RE = fr'({'|'.join(
+    ("CON", "PRN", "AUX", "CLOCK$", "NUL")
+    + tuple(f"{name:s}{num:d}" for name, num in itertools.product(("COM", "LPT"), range(0, 10)))
+    + tuple(
+        f"{name:s}{ssd:s}"
+        for name, ssd in itertools.product(
+            ("COM", "LPT"),
+            ("\N{SUPERSCRIPT ONE}", "\N{SUPERSCRIPT TWO}", "\N{SUPERSCRIPT THREE}"),
+        )
+    )
+)})'
+
 
 @functools.cache
 def preferredencoding():
@@ -679,6 +691,19 @@ def replace_insane(char):
     return result
 
 
+def _sanitize_windows_reserved_names(s):
+    # Append _res to invalid path names
+    # in order to maintain easy recognizability
+    # when a user accidentally writes to device files
+    # - CON.opus => CON_res.opus
+    def suffix_sanitize(match):
+        other = match.group(3) if match.group(3) else ''
+        if not match.group(2) and other:
+            return match.group(1) + other
+        return match.group(1) + '_res' + match.group(2) + other # suffix the reserved portion only
+    return re.sub(fr'{WINDOWS_RESERVED_NAMES_RE}(\.*)(.*$)', suffix_sanitize, s)
+
+
 def _sanitize_path_parts(parts):
     sanitized_parts = []
     for part in parts:
@@ -694,6 +719,7 @@ def _sanitize_path_parts(parts):
         # - trailing dots and spaces (`asdf...` => `asdf..#`)
         # - invalid chars (`<>` => `##`)
         sanitized_part = re.sub(r'[/<>:"\|\\?\*]|[\s.]$', '#', part)
+        sanitized_part = _sanitize_windows_reserved_names(sanitized_part)
         sanitized_parts.append(sanitized_part)
 
     return sanitized_parts
@@ -713,6 +739,11 @@ def sanitize_path(s, force=False):
     if normed.startswith('\\\\'):
         # UNC path (`\\SERVER\SHARE`) or device path (`\\.`, `\\?`)
         parts = normed.split('\\')
+        # allow user to write to explicitly declared legacy devices
+        if len(parts) == 4 and re.fullmatch(WINDOWS_RESERVED_NAMES_RE, parts[3]):
+            return '\\'.join(parts[:4])
+        # sanitize legacy name device otherwise
+        parts[3] = _sanitize_windows_reserved_names(parts[3])
         root = '\\'.join(parts[:4]) + '\\'
         parts = parts[4:]
     elif normed[1:2] == ':':