/*
* libjingle
* Copyright 2004 Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "talk/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