[cleanup] Misc (#16697)

Authored by: Grub4K, bashonly

Co-authored-by: bashonly <bashonly@protonmail.com>

yt_dlp/YoutubeDL.py

@@ -1313,6 +1313,7 @@ class YoutubeDL:
             )$''')
         SAFE_EXEC_CONVERSIONS = 'difq'
         UNSAFE_DEFAULT_CHARS = '"\' \n\t;&|^$%*<>{}()[]`#\\'
+        EXEC_ADVISORY_MSG = 'See  https://github.com/yt-dlp/yt-dlp/security/advisories/GHSA-69qj-pvh9-c5wg  for details'
 
         def _from_user_input(field):
             if field == ':':
@@ -1440,12 +1441,21 @@ class YoutubeDL:
             # Validate safety of exec commands
             if _exec:
                 if fmt[-1] not in SAFE_EXEC_CONVERSIONS:
-                    raise UnsafeExecExpansionError(f'Unsafe conversion(s) in exec command: {outtmpl!r}')
+                    raise UnsafeExecExpansionError(
+                        f'Unsafe conversion(s) in exec command: {outtmpl!r}\n'
+                        f'Conversions such as %()s are too dangerous to be used in '
+                        f'--exec command templates; use %()q instead. {EXEC_ADVISORY_MSG}')
                 elif any(unsafe_char in default for unsafe_char in UNSAFE_DEFAULT_CHARS):
                     if default == na:
-                        raise UnsafeExecExpansionError(f'Unsafe placeholder for exec command: {na!r}')
+                        raise UnsafeExecExpansionError(
+                            f'Unsafe placeholder for exec command: {na!r}\n'
+                            f'The --output-na-placeholder argument also applies to '
+                            f'--exec command templates. {EXEC_ADVISORY_MSG}')
                     else:
-                        raise UnsafeExecExpansionError(f'Unsafe default(s) in exec command: {outtmpl!r}')
+                        raise UnsafeExecExpansionError(
+                            f'Unsafe default(s) in exec command: {outtmpl!r}\n'
+                            f'Conversions are not applied to --exec command template defaults, '
+                            f'e.g. %(...|DEFAULT;)q. {EXEC_ADVISORY_MSG}')
 
             flags = outer_mobj.group('conversion') or ''
             str_fmt = f'{fmt[:-1]}s'

yt_dlp/downloader/external.py

@@ -11,6 +11,7 @@ import time
 from .fragment import FragmentFD
 from ..postprocessor.ffmpeg import EXT_TO_OUT_FORMATS, FFmpegPostProcessor
 from ..utils import (
+    DownloadError,
     Popen,
     RetryManager,
     _configuration_args,
@@ -136,8 +137,6 @@ class ExternalFD(FragmentFD):
             self.to_screen(f'[download] Writing temporary cookies file to "{self._cookies_tempfile}"')
         # real_download resets _cookies_tempfile; if it's None then save() will write to cookiejar.filename
         self.ydl.cookiejar.save(self._cookies_tempfile, True, True)
-        with open(self.ydl.cookiejar.filename or self._cookies_tempfile, "r") as file:
-            print("cookies", repr(file.read()))
         return self.ydl.cookiejar.filename or self._cookies_tempfile
 
     def _call_downloader(self, tmpfilename, info_dict):
@@ -224,8 +223,7 @@ class CurlFD(ExternalFD):
         else:
             cookies_file = self._write_cookies()
             if '=' in cookies_file:
-                # XXX: what to raise here?
-                raise RuntimeError('curl version too old or temp directory contains `=`; please use another downloader or update curl')
+                raise DownloadError('curl version too old or temp directory contains `=`; please use another downloader or update curl')
             assert cookies_file != '-'
             cmd += ['--cookie', cookies_file]