Remove unused libudev on Linux.

webrtc/media/devices/libudevsymboltable.cc

-/*
- *  Copyright (c) 2004 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-#include "webrtc/media/devices/libudevsymboltable.h"
-
-#include <dlfcn.h>
-
-#include "webrtc/base/logging.h"
-
-namespace cricket {
-
-#define LATE_BINDING_SYMBOL_TABLE_CLASS_NAME LIBUDEV_SYMBOLS_CLASS_NAME
-#define LATE_BINDING_SYMBOL_TABLE_SYMBOLS_LIST LIBUDEV_SYMBOLS_LIST
-#define LATE_BINDING_SYMBOL_TABLE_DLL_NAME "libudev.so.0"
-#include "webrtc/base/latebindingsymboltable.cc.def"
-#undef LATE_BINDING_SYMBOL_TABLE_CLASS_NAME
-#undef LATE_BINDING_SYMBOL_TABLE_SYMBOLS_LIST
-#undef LATE_BINDING_SYMBOL_TABLE_DLL_NAME
-
-bool IsWrongLibUDevAbiVersion(rtc::DllHandle libudev_0) {
-  rtc::DllHandle libudev_1 = dlopen("libudev.so.1",
-                                          RTLD_NOW|RTLD_LOCAL|RTLD_NOLOAD);
-  bool unsafe_symlink = (libudev_0 == libudev_1);
-  if (unsafe_symlink) {
-    // .0 and .1 are distinct ABIs, so if they point to the same thing then one
-    // of them must be wrong. Probably the old has been symlinked to the new in
-    // a misguided attempt at backwards compatibility.
-    LOG(LS_ERROR) << "libudev.so.0 and libudev.so.1 unsafely point to the"
-                     " same thing; not using libudev";
-  } else if (libudev_1) {
-    // If libudev.so.1 is resident but distinct from libudev.so.0, then some
-    // system library loaded the new ABI separately. This is not a problem for
-    // LateBindingSymbolTable because its symbol look-ups are restricted to its
-    // DllHandle, but having libudev.so.0 resident may cause problems for that
-    // system library because symbol names are not namespaced by DLL. (Although
-    // our use of RTLD_LOCAL should avoid most problems.)
-    LOG(LS_WARNING)
-        << "libudev.so.1 is resident but distinct from libudev.so.0";
-  }
-  if (libudev_1) {
-    // Release the refcount that we acquired above. (Does not unload the DLL;
-    // whoever loaded it still needs it.)
-    dlclose(libudev_1);
-  }
-  return unsafe_symlink;
-}
-
-}  // namespace cricket