From 45de8bf76e32b56e7beb427b99c64fb8e30c7db0 Mon Sep 17 00:00:00 2001
From: Dave Bort <dbort@google.com>
Date: Tue, 12 Sep 2017 16:39:53 -0700
Subject: [PATCH] Add generic VMAddress-related types

This will allow sharing code that is currently hard-coded to use (e.g.)
LinuxVMAddress or mach_vm_size_t.

Change-Id: I7bf20600c73d4ec7d2a029754f9043a236a38e5a
Reviewed-on: https://chromium-review.googlesource.com/677142
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Dave Bort <dbort@google.com>
---
 util/misc/address_types.h               | 69 +++++++++++++++++++++++++
 util/numeric/checked_vm_address_range.h | 36 +++++++++++++
 util/util.gyp                           |  2 +
 3 files changed, 107 insertions(+)
 create mode 100644 util/misc/address_types.h
 create mode 100644 util/numeric/checked_vm_address_range.h

diff --git a/util/misc/address_types.h b/util/misc/address_types.h
new file mode 100644
index 00000000..ce7694c3
--- /dev/null
+++ b/util/misc/address_types.h
@@ -0,0 +1,69 @@
+// Copyright 2017 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef CRASHPAD_UTIL_MISC_ADDRESS_TYPES_H_
+#define CRASHPAD_UTIL_MISC_ADDRESS_TYPES_H_
+
+#include <stdint.h>
+
+#include <type_traits>
+
+#include "build/build_config.h"
+
+#if defined(OS_MACOSX)
+#include <mach/mach_types.h>
+#elif defined(OS_WIN)
+#include "util/win/address_types.h"
+#elif defined(OS_LINUX)
+#include "util/linux/address_types.h"
+#else
+#error "Unhandled OS type"
+#endif
+
+namespace crashpad {
+
+#if DOXYGEN
+
+//! \brief Type used to represent an address in a process, potentially across
+//!     bitness.
+using VMAddress = uint64_t;
+
+//! \brief Type used to represent the size of a memory range (with a
+//!     VMAddress), potentially across bitness.
+using VMSize = uint64_t;
+
+#elif defined(OS_MACOSX)
+
+using VMAddress = mach_vm_address_t;
+using VMSize = mach_vm_size_t;
+
+#elif defined(OS_WIN)
+
+using VMAddress = WinVMAddress;
+using VMSize = WinVMSize;
+
+#elif defined(OS_LINUX)
+
+using VMAddress = LinuxVMAddress;
+using VMSize = LinuxVMSize;
+
+#endif
+
+//! \brief Type used to represent an offset from a VMAddress, potentially
+//!     across bitness.
+using VMOffset = std::make_signed<VMSize>::type;
+
+}  // namespace crashpad
+
+#endif  // CRASHPAD_UTIL_MISC_ADDRESS_TYPES_H_
diff --git a/util/numeric/checked_vm_address_range.h b/util/numeric/checked_vm_address_range.h
new file mode 100644
index 00000000..e792dba9
--- /dev/null
+++ b/util/numeric/checked_vm_address_range.h
@@ -0,0 +1,36 @@
+// Copyright 2017 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef CRASHPAD_UTIL_NUMERIC_CHECKED_VM_ADDRESS_RANGE_H_
+#define CRASHPAD_UTIL_NUMERIC_CHECKED_VM_ADDRESS_RANGE_H_
+
+#include "util/misc/address_types.h"
+#include "util/numeric/checked_address_range.h"
+
+namespace crashpad {
+
+//! \brief Ensures that a range, composed of a base and a size, does not
+//!     overflow the pointer type of the process it describes a range in.
+//!
+//! This class checks bases of type #VMAddress and sizes of type #VMSize against
+//! a process whose pointer type is either 32 or 64 bits wide.
+//!
+//! Aside from varying the overall range on the basis of a process’ pointer type
+//! width, this class functions very similarly to CheckedRange.
+using CheckedVMAddressRange =
+    internal::CheckedAddressRangeGeneric<VMAddress, VMSize>;
+
+}  // namespace crashpad
+
+#endif  // CRASHPAD_UTIL_NUMERIC_CHECKED_VM_ADDRESS_RANGE_H_
diff --git a/util/util.gyp b/util/util.gyp
index 31d4847e..f284bb21 100644
--- a/util/util.gyp
+++ b/util/util.gyp
@@ -110,6 +110,7 @@
         'mach/task_memory.cc',
         'mach/task_memory.h',
         'misc/address_sanitizer.h',
+        'misc/address_types.h',
         'misc/arraysize_unsafe.h',
         'misc/clock.h',
         'misc/clock_mac.cc',
@@ -157,6 +158,7 @@
         'numeric/checked_address_range.cc',
         'numeric/checked_address_range.h',
         'numeric/checked_range.h',
+        'numeric/checked_vm_address_range.h',
         'numeric/in_range_cast.h',
         'numeric/int128.h',
         'numeric/safe_assignment.h',