base/native_library_fuchsia.cc

   1 // Copyright 2018 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 <fcntl.h>
   8 #include <fuchsia/io/cpp/fidl.h>
   9 #include <lib/fdio/directory.h>
  10 #include <lib/fdio/io.h>
  11 #include <lib/zx/vmo.h>
  12 #include <stdio.h>
  13 #include <zircon/dlfcn.h>
  14 #include <zircon/status.h>
  15 #include <zircon/syscalls.h>
  16
  17 #include "base/base_paths_fuchsia.h"
  18 #include "base/files/file.h"
  19 #include "base/files/file_path.h"
  20 #include "base/fuchsia/fuchsia_logging.h"
  21 #include "base/notreached.h"
  22 #include "base/path_service.h"
  23 #include "base/posix/safe_strerror.h"
  24 #include "base/strings/strcat.h"
  25 #include "base/strings/string_piece.h"
  26 #include "base/strings/stringprintf.h"
  27 #include "base/strings/utf_string_conversions.h"
  28 #include "base/threading/thread_restrictions.h"
  29
  30 namespace base {
  31
  32 std::string NativeLibraryLoadError::ToString() const {
  33   return message;
  34 }
  35
  36 NativeLibrary LoadNativeLibraryWithOptions(const FilePath& library_path,
  37                                            const NativeLibraryOptions& options,
  38                                            NativeLibraryLoadError* error) {
  39   std::vector<base::FilePath::StringType> components;
  40   library_path.GetComponents(&components);
  41   if (components.size() != 1u) {
  42     NOTREACHED() << "library_path is a path, should be a filename: "
  43                  << library_path.MaybeAsASCII();
  44     return nullptr;
  45   }
  46
  47   FilePath computed_path;
  48   base::PathService::Get(DIR_SOURCE_ROOT, &computed_path);
  49   computed_path = computed_path.AppendASCII("lib").Append(components[0]);
  50
  51   // Use fdio_open_fd (a Fuchsia-specific API) here so we can pass the
  52   // appropriate FS rights flags to request executability.
  53   // TODO(1018538): Teach base::File about FLAG_EXECUTE on Fuchsia, and then
  54   // use it here instead of using fdio_open_fd() directly.
  55   base::ScopedFD fd;
  56   zx_status_t status = fdio_open_fd(
  57       computed_path.value().c_str(),
  58       fuchsia::io::OPEN_RIGHT_READABLE | fuchsia::io::OPEN_RIGHT_EXECUTABLE,
  59       base::ScopedFD::Receiver(fd).get());
  60   if (status != ZX_OK) {
  61     if (error) {
  62       error->message =
  63           base::StringPrintf("fdio_open_fd: %s", zx_status_get_string(status));
  64     }
  65     return nullptr;
  66   }
  67
  68   zx::vmo vmo;
  69   status = fdio_get_vmo_exec(fd.get(), vmo.reset_and_get_address());
  70   if (status != ZX_OK) {
  71     if (error) {
  72       error->message = base::StringPrintf("fdio_get_vmo_exec: %s",
  73                                           zx_status_get_string(status));
  74     }
  75     return nullptr;
  76   }
  77
  78   NativeLibrary result = dlopen_vmo(vmo.get(), RTLD_LAZY | RTLD_LOCAL);
  79   return result;
  80 }
  81
  82 void UnloadNativeLibrary(NativeLibrary library) {
  83   // dlclose() is a no-op on Fuchsia, so do nothing here.
  84 }
  85
  86 void* GetFunctionPointerFromNativeLibrary(NativeLibrary library,
  87                                           StringPiece name) {
  88   return dlsym(library, name.data());
  89 }
  90
  91 std::string GetNativeLibraryName(StringPiece name) {
  92   return StrCat({"lib", name, ".so"});
  93 }
  94
  95 std::string GetLoadableModuleName(StringPiece name) {
  96   return GetNativeLibraryName(name);
  97 }
  98
  99 }  // namespace base