base/native_library_posix.cc

   1 // Copyright 2011 The Chromium Authors
   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/notreached.h"
  12 #include "base/strings/strcat.h"
  13 #include "base/strings/string_piece.h"
  14 #include "base/strings/string_util.h"
  15 #include "base/strings/utf_string_conversions.h"
  16 #include "base/threading/scoped_blocking_call.h"
  17 #include "build/build_config.h"
  18
  19 namespace base {
  20
  21 std::string NativeLibraryLoadError::ToString() const {
  22   return message;
  23 }
  24
  25 NativeLibrary LoadNativeLibraryWithOptions(const FilePath& library_path,
  26                                            const NativeLibraryOptions& options,
  27                                            NativeLibraryLoadError* error) {
  28   // dlopen() opens the file off disk.
  29   ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
  30
  31   // We deliberately do not use RTLD_DEEPBIND by default.  For the history why,
  32   // please refer to the bug tracker.  Some useful bug reports to read include:
  33   // http://crbug.com/17943, http://crbug.com/17557, http://crbug.com/36892,
  34   // and http://crbug.com/40794.
  35   int flags = RTLD_LAZY;
  36 #if BUILDFLAG(IS_ANDROID) || !defined(RTLD_DEEPBIND)
  37   // Certain platforms don't define RTLD_DEEPBIND. Android dlopen() requires
  38   // further investigation, as it might vary across versions. Crash here to
  39   // warn developers that they're trying to rely on uncertain behavior.
  40   CHECK(!options.prefer_own_symbols);
  41 #else
  42   if (options.prefer_own_symbols)
  43     flags |= RTLD_DEEPBIND;
  44 #endif
  45   void* dl = dlopen(library_path.value().c_str(), flags);
  46   if (!dl && error)
  47     error->message = dlerror();
  48
  49   return dl;
  50 }
  51
  52 void UnloadNativeLibrary(NativeLibrary library) {
  53   int ret = dlclose(library);
  54   if (ret < 0) {
  55     DLOG(ERROR) << "dlclose failed: " << dlerror();
  56     NOTREACHED();
  57   }
  58 }
  59
  60 void* GetFunctionPointerFromNativeLibrary(NativeLibrary library,
  61                                           StringPiece name) {
  62   return dlsym(library, name.data());
  63 }
  64
  65 std::string GetNativeLibraryName(StringPiece name) {
  66   DCHECK(IsStringASCII(name));
  67   return StrCat({"lib", name, ".so"});
  68 }
  69
  70 std::string GetLoadableModuleName(StringPiece name) {
  71   return GetNativeLibraryName(name);
  72 }
  73
  74 }  // namespace base