win: Support reading process info cross-bitness

util/win/process_structs.h

+// Copyright 2015 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_WIN_PROCESS_STRUCTS_H_
+#define CRASHPAD_UTIL_WIN_PROCESS_STRUCTS_H_
+
+#include <windows.h>
+
+namespace crashpad {
+namespace process_types {
+
+namespace internal {
+
+struct Traits32 {
+  using Pad = DWORD;
+  using Integral = DWORD;

[Mark Mentovai, 2015/03/09 22:44:44]

Let’s have both signed and unsigned. Anything that’s supposed to be signed
should be declared with the proper type. Right now, everything’s unsigned. If
there really isn’t anything that’s supposed to be signed, we should at least
name this one Unsigned so that the signedness is clear at use sites.

[scottmg, 2015/03/09 23:23:57]

Done. I don't believe there are any that are signed.

[I didn't use Long and ULong similar to the Mac implementation as on Windows
ULONG means 4 bytes (and ULONG64 means 8 bytes) so that name would be confusing
in this file.]

+  using Pointer = DWORD;
+};
+
+struct Traits64 {
+  using Pad = DWORD64;
+  using Integral = DWORD64;
+  using Pointer = DWORD64;
+};
+
+}  // namespace internal
+
+//! \{
+
+//! \brief Selected structures from winternl.h, ntddk.h, and `dt ntdll!xxx`,
+//!     customized to have both x86 and x64 sizes available.
+//!
+//! The structure and field names follow the Windows names for clarity. We do,
+//! however, use plain integral types rather than pointer types. This is both
+//! easier to define, and avoids accidentally treating them as pointers into the
+//! current address space.
+//!
+//! The templates below should be instantiated with either internal::Traits32
+//! for structures targeting x86, or internal::Traits64 for x64.
+
+// We set packing to 1 so that we can explicitly control the layout to make it
+// match the OS defined structures.
+#pragma pack(push, 1)
+
+template <class Traits>
+struct PROCESS_BASIC_INFORMATION {
+  union {
+    DWORD ExitStatus;
+    typename Traits::Pad padding_for_x64_0;
+  };
+  typename Traits::Pointer PebBaseAddress;
+  typename Traits::Integral AffinityMask;
+  union {
+    DWORD BasePriority;
+    typename Traits::Pad padding_for_x64_1;
+  };
+  typename Traits::Integral UniqueProcessId;
+  typename Traits::Integral InheritedFromUniqueProcessId;
+};
+
+template <class Traits>
+struct LIST_ENTRY {
+  typename Traits::Pointer Flink;
+  typename Traits::Pointer Blink;
+};
+
+template <class Traits>
+struct UNICODE_STRING {
+  union {
+    struct {
+      USHORT Length;
+      USHORT MaximumLength;
+    };
+    typename Traits::Pad padding_for_x64;
+  };
+  typename Traits::Pointer Buffer;
+};
+
+template <class Traits>
+struct PEB_LDR_DATA {
+  ULONG Length;
+  DWORD Initialized;
+  typename Traits::Pointer SsHandle;
+  LIST_ENTRY<Traits> InLoadOrderModuleList;
+  LIST_ENTRY<Traits> InMemoryOrderModuleList;
+  LIST_ENTRY<Traits> InInitializationOrderModuleList;
+};
+
+template <class Traits>
+struct LDR_DATA_TABLE_ENTRY {
+  LIST_ENTRY<Traits> InLoadOrderLinks;
+  LIST_ENTRY<Traits> InMemoryOrderLinks;
+  LIST_ENTRY<Traits> InInitializationOrderLinks;
+  typename Traits::Pointer DllBase;
+  typename Traits::Pointer EntryPoint;
+  union {
+    ULONG SizeOfImage;
+    typename Traits::Pad padding_for_x86;

[Mark Mentovai, 2015/03/09 22:44:44]

x86 but not x64? Same question once later in the file.

[scottmg, 2015/03/09 23:23:57]

Oops, fixed.

+  };
+  UNICODE_STRING<Traits> FullDllName;
+  UNICODE_STRING<Traits> BaseDllName;
+  ULONG Flags;
+  USHORT ObsoleteLoadCount;
+  USHORT TlsIndex;
+  LIST_ENTRY<Traits> HashLinks;
+  ULONG TimeDateStamp;
+};
+
+template <class Traits>
+struct CURDIR {
+  UNICODE_STRING<Traits> DosPath;
+  typename Traits::Pointer Handle;
+};
+
+template <class Traits>
+struct STRING {
+  union {
+    struct {
+      DWORD Length;
+      DWORD MaximumLength;
+    };
+    typename Traits::Pad padding_for_x64;
+  };
+  typename Traits::Pointer Buffer;
+};
+
+template <class Traits>
+struct RTL_DRIVE_LETTER_CURDIR {
+  WORD Flags;
+  WORD Length;
+  DWORD TimeStamp;
+  STRING<Traits> DosPath;
+};
+
+template <class Traits>
+struct RTL_USER_PROCESS_PARAMETERS {
+  DWORD MaximumLength;
+  DWORD Length;
+  DWORD Flags;
+  DWORD DebugFlags;
+  typename Traits::Pointer ConsoleHandle;
+  union {
+    DWORD ConsoleFlags;
+    typename Traits::Pad padding_for_x86;
+  };
+  typename Traits::Pointer StandardInput;
+  typename Traits::Pointer StandardOutput;
+  typename Traits::Pointer StandardError;
+  CURDIR<Traits> CurrentDirectory;
+  UNICODE_STRING<Traits> DllPath;
+  UNICODE_STRING<Traits> ImagePathName;
+  UNICODE_STRING<Traits> CommandLine;
+  typename Traits::Pointer Environment;
+  DWORD StartingX;
+  DWORD StartingY;
+  DWORD CountX;
+  DWORD CountY;
+  DWORD CountCharsX;
+  DWORD CountCharsY;
+  DWORD FillAttribute;
+  DWORD WindowFlags;
+  DWORD ShowWindowFlags;
+  UNICODE_STRING<Traits> WindowTitle;
+  UNICODE_STRING<Traits> DesktopInfo;
+  UNICODE_STRING<Traits> ShellInfo;
+  UNICODE_STRING<Traits> RuntimeData;
+  RTL_DRIVE_LETTER_CURDIR<Traits> CurrentDirectores[32];  // sic.
+};
+
+template <class T>
+struct GdiHandleBufferCountForBitness;
+
+template <>
+struct GdiHandleBufferCountForBitness<internal::Traits32> {
+  enum { value = 34 };
+};
+template <>
+struct GdiHandleBufferCountForBitness<internal::Traits64> {
+  enum { value = 60 };
+};
+
+template <class Traits>
+struct PEB {
+  union {
+    struct {
+      BYTE InheritedAddressSpace;
+      BYTE ReadImageFileExecOptions;
+      BYTE BeingDebugged;
+      BYTE BitField;
+    };
+    typename Traits::Pad padding_for_x64_0;
+  };
+  typename Traits::Pointer Mutant;
+  typename Traits::Pointer ImageBaseAddress;
+  typename Traits::Pointer Ldr;
+  typename Traits::Pointer ProcessParameters;
+  typename Traits::Pointer SubSystemData;
+  typename Traits::Pointer ProcessHeap;
+  typename Traits::Pointer FastPebLock;
+  typename Traits::Pointer AtlThunkSListPtr;
+  typename Traits::Pointer IFEOKey;
+  union {
+    DWORD CrossProcessFlags;
+    typename Traits::Pad padding_for_x64_1;
+  };
+  typename Traits::Pointer KernelCallbackTable;
+  DWORD SystemReserved;
+  DWORD AtlThunkSListPtr32;
+  typename Traits::Pointer ApiSetMap;
+  union {
+    DWORD TlsExpansionCounter;
+    typename Traits::Pad padding_for_x64_2;
+  };
+  typename Traits::Pointer TlsBitmap;
+  DWORD TlsBitmapBits[2];
+  typename Traits::Pointer ReadOnlySharedMemoryBase;
+  typename Traits::Pointer SparePvoid0;
+  typename Traits::Pointer ReadOnlyStaticServerData;
+  typename Traits::Pointer AnsiCodePageData;
+  typename Traits::Pointer OemCodePageData;
+  typename Traits::Pointer UnicodeCaseTableData;
+  DWORD NumberOfProcessors;
+  DWORD NtGlobalFlag;
+  LARGE_INTEGER CriticalSectionTimeout;
+  typename Traits::Integral HeapSegmentReserve;
+  typename Traits::Integral HeapSegmentCommit;
+  typename Traits::Integral HeapDeCommitTotalFreeThreshold;
+  typename Traits::Integral HeapDeCommitFreeBlockThreshold;
+  DWORD NumberOfHeaps;
+  DWORD MaximumNumberOfHeaps;
+  typename Traits::Pointer ProcessHeaps;
+  typename Traits::Pointer GdiSharedHandleTable;
+  typename Traits::Pointer ProcessStarterHelper;
+  DWORD GdiDCAttributeList;
+  typename Traits::Pointer LoaderLock;
+  DWORD OSMajorVersion;
+  DWORD OSMinorVersion;
+  WORD OSBuildNumber;
+  WORD OSCSDVersion;
+  DWORD OSPlatformId;
+  DWORD ImageSubsystem;
+  DWORD ImageSubsystemMajorVersion;
+  union {
+    DWORD ImageSubsystemMinorVersion;
+    typename Traits::Pad padding_for_x64_3;
+  };
+  typename Traits::Integral ActiveProcessAffinityMask;
+  DWORD GdiHandleBuffer[GdiHandleBufferCountForBitness<Traits>::value];
+  typename Traits::Pointer PostProcessInitRoutine;
+  typename Traits::Pointer TlsExpansionBitmap;
+  DWORD TlsExpansionBitmapBits[32];
+  union {
+    DWORD SessionId;
+    typename Traits::Pad padding_for_x64_4;
+  };
+  ULARGE_INTEGER AppCompatFlags;
+  ULARGE_INTEGER AppCompatFlagsUser;
+  typename Traits::Pointer pShimData;
+  typename Traits::Pointer AppCompatInfo;
+  UNICODE_STRING<Traits> CSDVersion;
+  typename Traits::Pointer ActivationContextData;
+  typename Traits::Pointer ProcessAssemblyStorageMap;
+  typename Traits::Pointer SystemDefaultActivationContextData;
+  typename Traits::Pointer SystemAssemblyStorageMap;
+  typename Traits::Integral MinimumStackCommit;
+  typename Traits::Pointer FlsCallback;
+  LIST_ENTRY<Traits> FlsListHead;
+  typename Traits::Pointer FlsBitmap;
+  DWORD FlsBitmapBits[4];
+  DWORD FlsHighIndex;
+};
+
+#pragma pack(pop)
+
+//! \}
+
+}  // namespace process_types
+}  // namespace crashpad
+
+#endif  // CRASHPAD_UTIL_WIN_PROCESS_STRUCTS_H_