blob: 8bec1eff5b63f22b1be22336c7482dcfc5e2a8c2 [file] [log] [blame]
// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <memory>
#include <string>
#include <vector>
#include "base/base_export.h"
#include "base/files/file_path.h"
#include "build/build_config.h"
#if defined(OS_WIN)
#include <windows.h>
namespace base {
// Supports cached lookup of modules by address, with caching based on module
// address ranges.
// Cached lookup is necessary on Mac for performance, due to an inefficient
// dladdr implementation. See
// Cached lookup is beneficial on Windows to minimize use of the loader
// lock. Note however that the cache retains a handle to looked-up modules for
// its lifetime, which may result in pinning modules in memory that were
// transiently loaded by the OS.
class BASE_EXPORT ModuleCache {
// Module represents a binary module (executable or library) and its
// associated state.
class BASE_EXPORT Module {
Module() = default;
virtual ~Module() = default;
Module(const Module&) = delete;
Module& operator=(const Module&) = delete;
// Gets the base address of the module.
virtual uintptr_t GetBaseAddress() const = 0;
// Gets the opaque binary string that uniquely identifies a particular
// program version with high probability. This is parsed from headers of the
// loaded module.
// For binaries generated by GNU tools:
// Contents of the field.
// On Windows:
// GUID + AGE in the debug image headers of a module.
virtual std::string GetId() const = 0;
// Gets the debug basename of the module. This is the basename of the PDB
// file on Windows and the basename of the binary on other platforms.
virtual FilePath GetDebugBasename() const = 0;
// Gets the size of the module.
virtual size_t GetSize() const = 0;
// True if this is a native module.
virtual bool IsNative() const = 0;
// Gets the module containing |address| or nullptr if |address| is not within
// a module. The returned module remains owned by and has the same lifetime as
// the ModuleCache object.
const Module* GetModuleForAddress(uintptr_t address);
std::vector<const Module*> GetModules() const;
// Add a non-native module to the cache. Non-native modules represent regions
// of non-native executable code, like v8 generated code or compiled
// Java.
// Note that non-native modules may be embedded within native modules, as in
// the case of v8 builtin code compiled within Chrome. In that case
// GetModuleForAddress() will return the non-native module rather than the
// native module for the memory region it occupies.
void AddNonNativeModule(std::unique_ptr<Module> module);
void InjectModuleForTesting(std::unique_ptr<Module> module);
// Looks for a module containing |address| in |modules| returns the module if
// found, or null if not.
static Module* FindModuleForAddress(
const std::vector<std::unique_ptr<Module>>& modules,
uintptr_t address);
// Creates a Module object for the specified memory address. Returns null if
// the address does not belong to a module.
static std::unique_ptr<Module> CreateModuleForAddress(uintptr_t address);
// Unsorted vector of cached native modules. The number of loaded modules is
// generally much less than 100, and more frequently seen modules will tend to
// be added earlier and thus be closer to the front to the vector. So linear
// search to find modules should be acceptable.
std::vector<std::unique_ptr<Module>> native_modules_;
// Unsorted vector of non-native modules. Separate from native_modules_ to
// support preferential lookup of non-native modules embedded in native
// modules. See comment on AddNonNativeModule().
std::vector<std::unique_ptr<Module>> non_native_modules_;
} // namespace base