Add switch to disable sox integration and ffmpeg integration at runtime (#3500)

Summary:
Since libsox and ffmpeg extensions now depend on external libraries, their initialization processes might cause unrecoverable issue, such as segfault.

This commit adds environment variable to disable them so that importing torchaudio won't attempt to load these libraries.

Pull Request resolved: https://github.com/pytorch/audio/pull/3500

Differential Revision: D47808178

Pulled By: mthrok

fbshipit-source-id: 80c1c6b5f4bc608d4e209473702680db093c95ee

.github/workflows/unittest-windows-cpu.yml

@@ -45,6 +45,7 @@ jobs:
         export TORCHAUDIO_TEST_ALLOW_SKIP_IF_NO_MOD_sentencepiece=true
         export TORCHAUDIO_TEST_ALLOW_SKIP_IF_NO_AUDIO_OUT_DEVICE=true
         export TORCHAUDIO_TEST_ALLOW_SKIP_IF_NO_MACOS=true
+        export TORCHAUDIO_TEST_ALLOW_SKIP_IF_TEMPORARY_DISABLED=true
 
         .github/scripts/unittest-windows/setup_env.sh
         .github/scripts/unittest-windows/install.sh

torchaudio/_extension/__init__.py

@@ -2,7 +2,7 @@ import logging
 import os
 import sys
 
-from torchaudio._internal.module_utils import fail_with_message, is_module_available, no_op
+from torchaudio._internal.module_utils import eval_env, fail_with_message, is_module_available, no_op
 
 try:
     from .fb import _init_ffmpeg
@@ -57,14 +57,30 @@ if _IS_TORCHAUDIO_EXT_AVAILABLE:
 # At that point, this initialization should handle the case where
 # sox integration is built but libsox is not found.
 _SOX_INITIALIZED = False
-if is_module_available("torchaudio.lib._torchaudio_sox"):
+_USE_SOX = False if os.name == "nt" else eval_env("TORCHAUDIO_USE_SOX", True)
+_SOX_MODULE_AVAILABLE = is_module_available("torchaudio.lib._torchaudio_sox")
+if _USE_SOX and _SOX_MODULE_AVAILABLE:
     _init_sox()
     _SOX_INITIALIZED = True
 
 
+if os.name == "nt":
+    fail_if_no_sox = fail_with_message("requires sox extension, which is not supported on Windows.")
+elif not _USE_SOX:
+    fail_if_no_sox = fail_with_message("requires sox extension, but it is disabled. (TORCHAUDIO_USE_SOX=0)")
+elif not _SOX_MODULE_AVAILABLE:
+    fail_if_no_sox = fail_with_message(
+        "requires sox extension, but TorchAudio is not compiled with it. "
+        "Please build TorchAudio with libsox support. (BUILD_SOX=1)"
+    )
+else:
+    fail_if_no_sox = no_op
+
+
 # Initialize FFmpeg-related features
 _FFMPEG_EXT = None
-if _IS_TORCHAUDIO_EXT_AVAILABLE:
+_USE_FFMPEG = eval_env("TORCHAUDIO_USE_FFMPEG", True)
+if _USE_FFMPEG and _IS_TORCHAUDIO_EXT_AVAILABLE:
     try:
         _FFMPEG_EXT = _init_ffmpeg()
     except Exception:
@@ -76,15 +92,11 @@ if _IS_TORCHAUDIO_EXT_AVAILABLE:
         _LG.debug("Failed to initialize ffmpeg bindings", exc_info=True)
 
 
-fail_if_no_sox = (
-    no_op
-    if _SOX_INITIALIZED
-    else fail_with_message(
-        "requires sox extension, but TorchAudio is not compiled with it. Please build TorchAudio with libsox support."
-    )
-)
+if _USE_FFMPEG:
+    fail_if_no_ffmpeg = _fail_since_no_ffmpeg if _FFMPEG_EXT is None else no_op
+else:
+    fail_if_no_ffmpeg = fail_with_message("requires ffmpeg extension, but it is disabled. (TORCHAUDIO_USE_FFMPEG=0)")
 
-fail_if_no_ffmpeg = _fail_since_no_ffmpeg if _FFMPEG_EXT is None else no_op
 
 fail_if_no_rir = (
     no_op