base/native_library_posix.cc

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/native_library.h"
   6
   7 #include <dlfcn.h>
   8
   9 #include "base/files/file_path.h"
  10 #include "base/logging.h"
  11 #include "base/strings/strcat.h"
  12 #include "base/strings/string_piece.h"
  13 #include "base/strings/string_util.h"
  14 #include "base/strings/utf_string_conversions.h"
  15 #include "base/threading/scoped_blocking_call.h"
  16
  17 namespace base {
  18
  19 std::string NativeLibraryLoadError::ToString() const {
  20   return message;
  21 }
  22
  23 NativeLibrary LoadNativeLibraryWithOptions(const FilePath& library_path,
  24                                            const NativeLibraryOptions& options,
  25                                            NativeLibraryLoadError* error) {
  26   // dlopen() opens the file off disk.
  27   ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
  28
  29   // We deliberately do not use RTLD_DEEPBIND by default.  For the history why,
  30   // please refer to the bug tracker.  Some useful bug reports to read include:
  31   // http://crbug.com/17943, http://crbug.com/17557, http://crbug.com/36892,
  32   // and http://crbug.com/40794.
  33   int flags = RTLD_LAZY;
  34 #if defined(OS_ANDROID) || !defined(RTLD_DEEPBIND)
  35   // Certain platforms don't define RTLD_DEEPBIND. Android dlopen() requires
  36   // further investigation, as it might vary across versions. Crash here to
  37   // warn developers that they're trying to rely on uncertain behavior.
  38   CHECK(!options.prefer_own_symbols);
  39 #else
  40   if (options.prefer_own_symbols)
  41     flags |= RTLD_DEEPBIND;
  42 #endif
  43   void* dl = dlopen(library_path.value().c_str(), flags);
  44   if (!dl && error)
  45     error->message = dlerror();
  46
  47   return dl;
  48 }
  49
  50 void UnloadNativeLibrary(NativeLibrary library) {
  51   int ret = dlclose(library);
  52   if (ret < 0) {
  53     DLOG(ERROR) << "dlclose failed: " << dlerror();
  54     NOTREACHED();
  55   }
  56 }
  57
  58 void* GetFunctionPointerFromNativeLibrary(NativeLibrary library,
  59                                           StringPiece name) {
  60   return dlsym(library, name.data());
  61 }
  62
  63 std::string GetNativeLibraryName(StringPiece name) {
  64   DCHECK(IsStringASCII(name));
  65   return StrCat({"lib", name, ".so"});
  66 }
  67
  68 std::string GetLoadableModuleName(StringPiece name) {
  69   return GetNativeLibraryName(name);
  70 }
  71
  72 }  // namespace base