Some plumbing for the beginning of getting handles into snapshot/minidump

compat/non_win/dbghelp.h

 // Copyright 2014 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,
@@ skipping 603 matching lines @@
 //! to the exception that triggered the snapshot to be taken.
 struct __attribute__((packed, aligned(4))) MINIDUMP_MEMORY_LIST {
   //! \brief The number of memory regions present in the #MemoryRanges array.
   uint32_t NumberOfMemoryRanges;
 
   //! \brief Structures identifying each memory region present in the minidump
   //!     file.
   MINIDUMP_MEMORY_DESCRIPTOR MemoryRanges[0];
 };
 
+//! \brief Contains the state of an individual system handle at the time the
+//!     snapshot was taken.
+//!
+//! \sa MINIDUMP_HANDLE_DESCRIPTOR_2
+struct __attribute__((packed, aligned(4))) MINIDUMP_HANDLE_DESCRIPTOR {
+  //! \brief The operating system handle value.
+  uint64_t Handle;
+
+  //! \brief An RVA to a MINIDUMP_STRING structure that specifies the object
+  //!     type of the handle. This member can be zero.
+  RVA TypeNameRva;
+
+  //! \brief An RVA to a MINIDUMP_STRING structure that specifies the object
+  //!     name of the handle. This member can be zero.
+  RVA ObjectNameRva;
+
+  //! \brief The meaning of this member depends on the handle type and the
+  //!     operating system. On Windows, this corresponds to `OBJ_INHERIT`,

[Mark Mentovai, 2015/10/14 23:55:13]

You got this documentation verbatim from Microsoft, but the meaning of
“operating system” to them is entirely different than its meaning in Crashpad,
which runs on non-Microsoft operating systems.

Your “on Windows” addition is then a little weird, because HANDLEs aren’t a
thing on non-Windows at all, and we wouldn’t see a MINIDUMP_HANDLE_DESCRIPTOR. I
think that Microsoft meant what we’d call the OS version.

Same for the remainder of the fields in this structure.

[scottmg, 2015/10/16 20:51:01]

Done.

+  //!     `OBJ_CASE_INSENSITIVE`, etc.
+  uint32_t Attributes;
+
+  //! \brief The meaning of this member depends on the handle type and the
+  //!     operating system. On Windows, this is the value of an `ACCESS_MASK`.
+  uint32_t GrantedAccess;
+
+  //! \brief The meaning of this member depends on the handle type and the
+  //!     operating system. On Windows, this is the number of open handles to
+  //!     the object that this handle refers to.
+  uint32_t HandleCount;
+
+  //! \brief The meaning of this member depends on the handle type and the
+  //!     operating system. On Windows, this is the number kernel references
+  //!     to the object that this handle refers to.
+  uint32_t PointerCount;
+};
+
+//! \brief Contains the state of an individual system handle at the time the
+//!     snapshot was taken.
+//!
+//! \sa MINIDUMP_HANDLE_DESCRIPTOR
+struct __attribute__((packed, aligned(4))) MINIDUMP_HANDLE_DESCRIPTOR_2
+    : public MINIDUMP_HANDLE_DESCRIPTOR {
+  //! \brief An RVA to a MINIDUMP_HANDLE_OBJECT_INFORMATION structure that
+  //!     specifies object-specific information. This member can be zero if
+  //!     there is no extra information.
+  RVA ObjectInfoRva;
+
+  //! \brief Must be zero.
+  uint32_t Reserved0;
+};
+
+//! \brief Represents the header for a handle data stream.
+struct __attribute((packed, aligned(4))) MINIDUMP_HANDLE_DATA_STREAM {
+  //! \brief The size of the header information for the stream, in bytes. This
+  //!     value is `sizeof(MINIDUMP_HANDLE_DATA_STREAM)`.
+  uint32_t SizeOfHeader;
+
+  //! \brief The size of a descriptor in the stream, in bytes. This value is
+  //!     `sizeof(MINIDUMP_HANDLE_DESCRIPTOR)` or
+  //!     `sizeof(MINIDUMP_HANDLE_DESCRIPTOR_2)`.
+  uint32_t SizeOfDescriptor;
+
+  //! \brief The number of descriptors in the stream.
+  uint32_t NumberOfDescriptors;
+
+  //! \brief Must be zero.
+  uint32_t Reserved;
+};
+
 //! \anchor MINIDUMP_MISCx
 //! \name MINIDUMP_MISC*
 //!
 //! \brief Field validity flag values for MINIDUMP_MISC_INFO::Flags1.
 //! \{
 
 //! \brief MINIDUMP_MISC_INFO::ProcessId is valid.
 #define MINIDUMP_MISC1_PROCESS_ID 0x00000001
 
 //! \brief The time-related fields in MINIDUMP_MISC_INFO are valid.
@@ skipping 272 matching lines @@
   //!  - A MINIDUMP_MODULE_LIST stream. All loaded modules are present.
   //!  - Typically, a MINIDUMP_MEMORY_LIST stream containing duplicate pointers
   //!    to the stack memory regions also referenced by the MINIDUMP_THREAD_LIST
   //!    stream. This type of minidump file also includes a
   //!    MINIDUMP_MEMORY_DESCRIPTOR containing the 256 bytes centered around
   //!    the exception address or the instruction pointer.
   MiniDumpNormal = 0x00000000,
 };
 
 #endif  // CRASHPAD_COMPAT_NON_WIN_DBGHELP_H_