format.rs

//! Minidump structure definitions.
//!
//! Types defined here should match those defined in [Microsoft's headers][msdn]. Additionally
//! some [Breakpad][breakpad] and [Crashpad][crashpad] extension types are defined here and should
//! match the definitions from those projects.
//!
//! # Type Layouts
//!
//! This library isn't a "proper" minidump-sys library because it doesn't use repr attributes
//! to force Rust to layout these structs identically to how they're laid out in memory.
//!
//! The reasons for this are 3-fold:
//!
//! 1. It isn't necessary because we specify how to serialize/deserialize things with `scroll`
//!    via `derive(Pread, Pwrite)` which uses the declared field order and not the in-memory
//!    layout, and assumes everything is packed anyway, which as a rule, minidump types are.
//!    Specifically they're packed to align 4, but Microsoft is mercifully very attentive to
//!    its type layouts so we're not aware of anywhere where packing to align 1 would change
//!    offsets. Packing is mostly just there so 32-bit and 64-bit definitely agree on offsets.
//!
//! 2. We would have to mark several types as `repr(packed(4))`, making them dangerous to use
//!    as several of the fields would become misaligned. This would create a bunch of
//!    unnecessary and brittle `unsafe`.
//!
//! 3. It's not *actually* that useful to have structs with precise in-memory layouts since
//!    a minidump parser needs to accept both little-endian and big-endian minidumps, and
//!    is therefore swizzling the bytes of all the values anyway. Also it's dangerous to
//!    reinterpret a pile of memory as arbitrary types without validation!
//!
//! [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/
//! [breakpad]: https://chromium.googlesource.com/breakpad/breakpad/
//! [crashpad]: https://chromium.googlesource.com/crashpad/crashpad/+/master/README.md
#![allow(non_camel_case_types)]
#![allow(non_upper_case_globals)]
#![allow(clippy::upper_case_acronyms)]

use std::fmt;

use bitflags::bitflags;
use enum_primitive_derive::Primitive;
use scroll::{Endian, Pread, Pwrite, SizeWith};
use smart_default::SmartDefault;

/// An offset from the start of the minidump file.
pub type RVA = u32;
pub type RVA64 = u64;

/// The 4-byte magic number at the start of a minidump file.
///
/// In little endian this spells 'MDMP'.
pub const MINIDUMP_SIGNATURE: u32 = 0x504d444d;

/// The version of the minidump format.
pub const MINIDUMP_VERSION: u32 = 42899;

/// The header at the start of a minidump file.
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_header
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_HEADER {
    /// This should be [`MINIDUMP_SIGNATURE`][signature].
    ///
    /// [signature]: constant.MINIDUMP_SIGNATURE.html
    pub signature: u32,
    /// This should be [`MINIDUMP_VERSION`][version].
    ///
    /// [version]: constant.MINIDUMP_VERSION.html
    pub version: u32,
    /// The number of streams contained in the stream directory.
    pub stream_count: u32,
    /// The offset to the stream directory within the minidump. This usually points
    /// to immediately after the header. The stream directory is an array containing
    /// `stream_count` [`MINIDUMP_DIRECTORY`][dir] entries.
    ///
    /// [dir]: struct.MINIDUMP_DIRECTORY.html
    pub stream_directory_rva: RVA,
    pub checksum: u32,
    pub time_date_stamp: u32,
    pub flags: u64,
}

/// A location within a minidump file comprised of an offset and a size.
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_location_descriptor
#[derive(Debug, Copy, Default, Clone, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_LOCATION_DESCRIPTOR {
    /// The size of this data.
    pub data_size: u32,
    /// The offset to this data within the minidump file.
    pub rva: RVA,
}

impl From<u8> for MINIDUMP_LOCATION_DESCRIPTOR {
    fn from(_val: u8) -> Self {
        Self::default()
    }
}

/// A range of memory contained within a minidump consisting of a base address and a
/// location descriptor.
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_memory_descriptor
#[derive(Debug, Copy, Clone, Default, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_MEMORY_DESCRIPTOR {
    /// The base address of this memory range from the process.
    pub start_of_memory_range: u64,
    /// The offset and size of the actual bytes of memory contained in this dump.
    pub memory: MINIDUMP_LOCATION_DESCRIPTOR,
}

/// A large range of memory contained within a minidump (usually a full dump)
/// consisting of a base address and a size.
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_memory_descriptor64
#[derive(Debug, Copy, Clone, Default, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_MEMORY_DESCRIPTOR64 {
    /// The base address of this memory range from the process.
    pub start_of_memory_range: u64,
    /// The size of this data.
    pub data_size: u64,
}

/// Information about a data stream contained in a minidump file.
///
/// The minidump header contains a pointer to a list of these structs which allows locating
/// specific streams in the dump.
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_directory
#[derive(Debug, Clone, Default, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_DIRECTORY {
    /// This is usually one of the values in [`MINIDUMP_STREAM_TYPE`][ty] for known stream types,
    /// but user streams can have arbitrary values.
    ///
    /// [ty]: enum.MINIDUMP_STREAM_TYPE.html
    pub stream_type: u32,
    /// The location of the stream contents within the dump.
    pub location: MINIDUMP_LOCATION_DESCRIPTOR,
}

/// The types of known minidump data streams.
///
/// Most of these values are derived from the [Microsoft enum][msdn] of the same name, but
/// the values after `LastReservedStream` are Breakpad and Crashpad extensions.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ne-minidumpapiset-minidump_stream_type
#[repr(u32)]
#[derive(Copy, Clone, PartialEq, Eq, Debug, Primitive)]
pub enum MINIDUMP_STREAM_TYPE {
    /// An unused stream directory entry
    UnusedStream = 0,
    ReservedStream0 = 1,
    ReservedStream1 = 2,
    /// The list of threads from the process
    ///
    /// See [`MINIDUMP_THREAD`].
    ///
    /// Microsoft declares a [`MINIDUMP_THREAD_LIST`][list] struct which is the actual format
    /// of this stream, but it is a variable-length struct so no matching definition is provided
    /// in this crate.
    ///
    /// [list]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_thread_list
    ThreadListStream = 3,
    /// The list of executable modules from the process
    ///
    /// See [`MINIDUMP_MODULE`].
    ///
    /// Microsoft declares a [`MINIDUMP_MODULE_LIST`][list] struct which is the actual format
    /// of this stream, but it is a variable-length struct so no matching definition is provided
    /// in this crate.
    ///
    /// [list]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_module_list
    ModuleListStream = 4,
    /// The list of memory regions from the process contained within this dump
    ///
    /// See [`MINIDUMP_MEMORY_DESCRIPTOR`].
    ///
    /// Microsoft declares a [`MINIDUMP_MEMORY_LIST`][list] struct which is the actual format
    /// of this stream, but it is a variable-length struct so no matching definition is provided
    /// in this crate.
    ///
    /// [list]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_memory_list
    MemoryListStream = 5,
    /// Information about the exception that caused the process to exit
    ///
    /// See [`MINIDUMP_EXCEPTION_STREAM`].
    ExceptionStream = 6,
    /// System information
    ///
    /// See [`MINIDUMP_SYSTEM_INFO`].
    SystemInfoStream = 7,
    ThreadExListStream = 8,
    /// The list of large memory regions from the process contained within this dump
    ///
    /// See [`MINIDUMP_MEMORY_DESCRIPTOR64`].
    ///
    /// Microsoft declares a [`MINIDUMP_MEMORY64_LIST`][list] struct which is the actual format
    /// of this stream, but it is a variable-length struct so no matching definition is provided
    /// in this crate.
    ///
    /// [list]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_memory64_list
    Memory64ListStream = 9,
    CommentStreamA = 10,
    CommentStreamW = 11,
    HandleDataStream = 12,
    FunctionTable = 13,
    /// The list of executable modules from the process that were unloaded by the time of the crash
    ///
    /// See [`MINIDUMP_UNLOADED_MODULE`].
    ///
    /// Microsoft declares a [`MINIDUMP_UNLOADED_MODULE_LIST`][list] struct which is the actual
    /// format of this stream, but it is a variable-length struct so no matching definition is
    /// in this crate.
    ///
    /// Note that unlike other lists, this one has the newer "extended" header.
    ///
    /// [list]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_unloaded_module_list
    UnloadedModuleListStream = 14,
    /// Miscellaneous process and system information
    ///
    /// See ['MINIDUMP_MISC_INFO'].
    MiscInfoStream = 15,
    /// Information about memory regions from the process
    ///
    /// See ['MINIDUMP_MEMORY_INFO_LIST'].
    MemoryInfoListStream = 16,
    ThreadInfoListStream = 17,
    HandleOperationListStream = 18,
    TokenStream = 19,
    JavaScriptDataStream = 20,
    SystemMemoryInfoStream = 21,
    ProcessVmCountersStream = 22,
    IptTraceStream = 23,
    /// Names of threads
    ///
    /// See ['MINIDUMP_THREAD_NAME'].
    ThreadNamesStream = 24,
    /* Windows CE types, the list  is available here https://docs.microsoft.com/en-us/previous-versions/windows/embedded/ms939649(v=msdn.10) */
    /// Start of the Windows CE enumerated list, unused.
    ceStreamNull = 0x00008000,
    /// System-wide information about the device and operating system where the fault occurred. Windows CE-specific.
    ceStreamSystemInfo = 0x00008001,
    /// Exception record and context for the exception that caused the dump file creation. Windows CE-specific.
    ceStreamException = 0x00008002,
    /// Modules that were active on the device at the time the dump file was created. Windows CE-specific.
    ceStreamModuleList = 0x00008003,
    /// Processes that were active on the device at the time the dump file was created. Windows CE-specific.
    ceStreamProcessList = 0x00008004,
    /// Threads that were active on the device at the time the dump file was created. Windows CE-specific.
    ceStreamThreadList = 0x00008005,
    /// List of thread context records. Windows CE-specific.
    ceStreamThreadContextList = 0x00008006,
    /// List of thread callstack records. Windows CE-specific.
    ceStreamThreadCallStackList = 0x00008007,
    /// List of virtual memory dumps. Windows CE-specific.
    ceStreamMemoryVirtualList = 0x00008008,
    /// List of physical memory dumps. Windows CE-specific.
    ceStreamMemoryPhysicalList = 0x00008009,
    /// Bucketing parameters for Watson server. Windows CE-specific.
    ceStreamBucketParameters = 0x0000800a,
    /// Undocumented Windows CE-specific stream.
    ceStreamProcessModuleMap = 0x0000800b,
    /// Undocumented Windows CE-specific stream.
    ceStreamDiagnosisList = 0x0000800c,
    /// Last stream reserved for use by Windows Operating Systems.
    LastReservedStream = 0x0000ffff,
    /* Breakpad extension types.  0x4767 = "Gg" */
    /// Additional process information (Breakpad extension)
    ///
    /// See ['MINIDUMP_BREAKPAD_INFO'].
    BreakpadInfoStream = 0x47670001,
    /// Assertion information (Breakpad extension)
    ///
    /// See ['MINIDUMP_ASSERTION_INFO'].
    AssertionInfoStream = 0x47670002,
    /* These are additional minidump stream values which are specific to
     * the linux breakpad implementation. */
    /// The contents of /proc/cpuinfo from a Linux system
    LinuxCpuInfo = 0x47670003,
    /// The contents of /proc/self/status from a Linux system
    LinuxProcStatus = 0x47670004,
    /// The contents of /etc/lsb-release from a Linux system
    LinuxLsbRelease = 0x47670005,
    /// The contents of /proc/self/cmdline from a Linux system
    LinuxCmdLine = 0x47670006,
    /// The contents of /proc/self/environ from a Linux system
    LinuxEnviron = 0x47670007,
    /// The contents of /proc/self/auxv from a Linux system
    LinuxAuxv = 0x47670008,
    /// The contents of /proc/self/maps from a Linux system
    LinuxMaps = 0x47670009,
    /// Information from the Linux dynamic linker useful for writing core dumps
    ///
    /// See ['DSO_DEBUG_64'] and ['DSO_DEBUG_32'].
    LinuxDsoDebug = 0x4767000A,
    // Crashpad extension types. 0x4350 = "CP"
    /// Crashpad-specific information containing annotations.
    ///
    /// See [`MINIDUMP_CRASHPAD_INFO`].
    CrashpadInfoStream = 0x43500001,

    /// Data from the __DATA,__crash_info section of every module which contains
    /// one that has useful data. Only available on macOS. 0x4D7A = "Mz".
    ///
    /// See ['MINIDUMP_MAC_CRASH_INFO'].
    MozMacosCrashInfoStream = 0x4d7a0001,
}

impl From<MINIDUMP_STREAM_TYPE> for u32 {
    fn from(ty: MINIDUMP_STREAM_TYPE) -> Self {
        ty as u32
    }
}

/// The name of a thread, found in the ThreadNamesStream.
#[derive(Debug, Clone, Default, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_THREAD_NAME {
    /// The id of the thread.
    pub thread_id: u32,
    /// Where the name of the thread is stored (yes, the legendary RVA64 is real!!).
    pub thread_name_rva: RVA64,
}

/// Information about a single module (executable or shared library) from a minidump
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_module
#[derive(Debug, Clone, Default, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_MODULE {
    /// The base address of the executable image in memory.
    pub base_of_image: u64,
    /// The size of the executable image in memory, in bytes.
    pub size_of_image: u32,
    /// The checksum value from the PE headers.
    pub checksum: u32,
    /// The timestamp value from the PE headers in `time_t` format.
    pub time_date_stamp: u32,
    /// An offset to a length-prefixed UTF-16LE string containing the name of the module.
    pub module_name_rva: RVA,
    /// Version information for this module.
    pub version_info: VS_FIXEDFILEINFO,
    /// The location of a CodeView record describing debug information for this module.
    ///
    /// This should be one of [`CV_INFO_PDB70`][pdb70], [`CV_INFO_PDB20`][pdb20], or
    /// [`CV_INFO_ELF`][elf]. `PDB70` is the most common in practice, describing a standalone PDB
    /// file by way of GUID, age, and PDB filename, and `ELF` is a Breakpad extension for
    /// describing ELF modules with Build IDs.
    ///
    /// See [Matching Debug Information][dbg] for more information.
    ///
    /// [dbg]: http://www.debuginfo.com/articles/debuginfomatch.html
    /// [pdb70]: struct.CV_INFO_PDB70.html
    /// [pdb20]: struct.CV_INFO_PDB20.html
    /// [elf]: struct.CV_INFO_ELF.html
    pub cv_record: MINIDUMP_LOCATION_DESCRIPTOR,
    /// The location of an `IMAGE_DEBUG_MISC` record describing debug information for this module.
    pub misc_record: MINIDUMP_LOCATION_DESCRIPTOR,
    pub reserved0: [u32; 2],
    pub reserved1: [u32; 2],
}

/// Information about a single unloaded module (executable or shared library) from a minidump.
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_unloaded_module
#[derive(Debug, Clone, Default, Pread, SizeWith)]
pub struct MINIDUMP_UNLOADED_MODULE {
    /// The base address of the executable image in memory (when it was loaded).
    pub base_of_image: u64,
    /// The size of the executable image in memory, in bytes.
    pub size_of_image: u32,
    /// The checksum value from the PE headers.
    pub checksum: u32,
    /// The timestamp value from the PE headers in `time_t` format.
    pub time_date_stamp: u32,
    /// An offset to a length-prefixed UTF-16LE string containing the name of the module.
    pub module_name_rva: RVA,
}

/// Version information for a file
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/verrsrc/ns-verrsrc-vs_fixedfileinfo
#[derive(Debug, Clone, Default, Pread, Pwrite, SizeWith)]
pub struct VS_FIXEDFILEINFO {
    /// Contains the value of `VS_FFI_SIGNATURE`
    pub signature: u32,
    /// Should contain the value of `VS_FFI_STRUCVERSION`
    pub struct_version: u32,
    pub file_version_hi: u32,
    pub file_version_lo: u32,
    pub product_version_hi: u32,
    pub product_version_lo: u32,
    pub file_flags_mask: u32,
    pub file_flags: u32,
    pub file_os: u32,
    pub file_type: u32,
    pub file_subtype: u32,
    pub file_date_hi: u32,
    pub file_date_lo: u32,
}

/// The expected value of `VS_FIXEDFILEINFO.signature`
pub const VS_FFI_SIGNATURE: u32 = 0xfeef04bd;

/// The expected value of `VS_FIXEDFILEINFO.struct_version`
pub const VS_FFI_STRUCVERSION: u32 = 0x00010000;

/// Known values for the `signature` field of CodeView records
///
/// In addition to the two CodeView record formats used for linking
/// to external pdb files it is possible for debugging data to be carried
/// directly in the CodeView record itself.  These signature values will
/// be found in the first 4 bytes of the CodeView record.  Additional values
/// not commonly experienced in the wild are given by ["Microsoft Symbol and
/// Type Information"][sym] section 7.2.  An in-depth description of the CodeView 4.1 format
/// is given by ["Undocumented Windows 2000 Secrets"][win2k], Windows 2000 Debugging Support/
/// Microsoft Symbol File Internals/CodeView Subsections.
///
/// [sym]: http://web.archive.org/web/20070915060650/http://www.x86.org/ftp/manuals/tools/sym.pdf
/// [win2k]: https://dl.acm.org/citation.cfm?id=375734
#[repr(u32)]
#[derive(Copy, Clone, PartialEq, Eq, Debug, Primitive)]
pub enum CvSignature {
    /// PDB 2.0 CodeView data: 'NB10': [`CV_INFO_PDB20`]
    Pdb20 = 0x3031424e,
    /// PDB 7.0 CodeView data: 'RSDS': [`CV_INFO_PDB70`]
    Pdb70 = 0x53445352,
    /// ELF Build ID, a Breakpad extension: 'BpEL': [`CV_INFO_ELF`]
    Elf = 0x4270454c,
    /// CodeView 4.10: 'NB09'
    Cv41 = 0x3930424e,
    /// CodeView 5.0: 'NB11'
    Cv50 = 0x3131424e,
}

/// CodeView debug information in the older PDB 2.0 ("NB10") format.
///
/// This struct is defined as variable-length in C with a trailing PDB filename member.
#[derive(Debug, Clone)]
pub struct CV_INFO_PDB20 {
    /// This field will always be [`CvSignature::Pdb20`].
    pub cv_signature: u32,
    pub cv_offset: u32,
    pub signature: u32,
    pub age: u32,
    /// The PDB filename as a zero-terminated byte string
    pub pdb_file_name: Vec<u8>,
}

impl<'a> scroll::ctx::TryFromCtx<'a, Endian> for CV_INFO_PDB20 {
    type Error = scroll::Error;

    fn try_from_ctx(src: &[u8], endian: Endian) -> Result<(Self, usize), Self::Error> {
        let offset = &mut 0;
        Ok((
            CV_INFO_PDB20 {
                cv_signature: src.gread_with(offset, endian)?,
                cv_offset: src.gread_with(offset, endian)?,
                signature: src.gread_with(offset, endian)?,
                age: src.gread_with(offset, endian)?,
                pdb_file_name: {
                    let size = src.len() - *offset;
                    src.gread_with::<&[u8]>(offset, size)?.to_owned()
                },
            },
            *offset,
        ))
    }
}

/// CodeView debug information in the current PDB 7.0 ("RSDS") format.
///
/// This struct is defined as variable-length in C with a trailing PDB filename member.
#[derive(Debug, Clone)]
pub struct CV_INFO_PDB70 {
    /// This will always be [`CvSignature::Pdb70`]
    pub cv_signature: u32,
    /// A unique identifer for a module created on first build.
    pub signature: GUID,
    /// A counter, incremented for each rebuild that updates the PDB file.
    pub age: u32,
    /// The PDB filename as a zero-terminated byte string
    pub pdb_file_name: Vec<u8>,
}

impl<'a> scroll::ctx::TryFromCtx<'a, Endian> for CV_INFO_PDB70 {
    type Error = scroll::Error;

    fn try_from_ctx(src: &[u8], endian: Endian) -> Result<(Self, usize), Self::Error> {
        let offset = &mut 0;
        Ok((
            CV_INFO_PDB70 {
                cv_signature: src.gread_with(offset, endian)?,
                signature: src.gread_with(offset, endian)?,
                age: src.gread_with(offset, endian)?,
                pdb_file_name: {
                    let size = src.len() - *offset;
                    src.gread_with::<&[u8]>(offset, size)?.to_owned()
                },
            },
            *offset,
        ))
    }
}

/// A GUID as specified in Rpcdce.h
///
/// Matches the [Microsoft struct][msdn] of the same name.
///
/// # Display
///
/// There are two `Display` implementations for GUIDs. The regular formatting is lowercase with
/// hyphens. The alternate formatting used with `#` is the symbol server format (uppercase without
/// hyphens).
///
/// ```
/// use minidump_common::format::GUID;
///
/// let guid = GUID { data1: 10, data2: 11, data3: 12, data4: [1,2,3,4,5,6,7,8] };
///
/// // default formatting
/// assert_eq!("0000000a-000b-000c-0102-030405060708", guid.to_string());
///
/// // symbol server formatting
/// assert_eq!("0000000A000B000C0102030405060708", format!("{:#}", guid));
/// ```
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/guiddef/ns-guiddef-guid
#[derive(Clone, Copy, Debug, PartialEq, Eq, Pread, Pwrite, SizeWith)]
pub struct GUID {
    pub data1: u32,
    pub data2: u16,
    pub data3: u16,
    pub data4: [u8; 8],
}

/// Creates a GUID from a raw byte array. It is assumed that the components in
/// the array are in big-endian order.
///
/// ```
/// use minidump_common::format::GUID;
///
/// let mut buf = [0u8; 16];
/// buf[0..4].copy_from_slice(&0xdeadc0deu32.to_be_bytes());
/// buf[4..6].copy_from_slice(&0xb105u16.to_be_bytes());
/// buf[6..8].copy_from_slice(&0xc0deu16.to_be_bytes());
/// buf[8..].copy_from_slice(&[1, 2, 3, 4, 5, 6, 7, 8]);
///
/// let guid: GUID = buf.into();
///
/// let expected = GUID { data1: 0xdeadc0de, data2: 0xb105, data3: 0xc0de, data4: [1, 2, 3, 4, 5, 6, 7, 8] };
///
/// assert_eq!(guid, expected);
/// ```
impl From<[u8; 16]> for GUID {
    fn from(uuid: [u8; 16]) -> Self {
        let data1 = (uuid[0] as u32) << 24
            | (uuid[1] as u32) << 16
            | (uuid[2] as u32) << 8
            | uuid[3] as u32;
        let data2 = (uuid[4] as u16) << 8 | uuid[5] as u16;
        let data3 = (uuid[6] as u16) << 8 | uuid[7] as u16;
        let mut data4 = [0u8; 8];
        data4.copy_from_slice(&uuid[8..]);

        Self {
            data1,
            data2,
            data3,
            data4,
        }
    }
}

impl fmt::Display for GUID {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        // NB: This formatting is not endianness aware. GUIDs read from LE minidumps are printed
        // with reversed fields.
        if f.alternate() {
            write!(
                f,
                "{:08X}{:04X}{:04X}{:02X}{:02X}{:02X}{:02X}{:02X}{:02X}{:02X}{:02X}",
                self.data1,
                self.data2,
                self.data3,
                self.data4[0],
                self.data4[1],
                self.data4[2],
                self.data4[3],
                self.data4[4],
                self.data4[5],
                self.data4[6],
                self.data4[7],
            )
        } else {
            write!(
                f,
                "{:08x}-{:04x}-{:04x}-{:02x}{:02x}-{:02x}{:02x}{:02x}{:02x}{:02x}{:02x}",
                self.data1,
                self.data2,
                self.data3,
                self.data4[0],
                self.data4[1],
                self.data4[2],
                self.data4[3],
                self.data4[4],
                self.data4[5],
                self.data4[6],
                self.data4[7],
            )
        }
    }
}

/// An ELF Build ID.
///
/// Modern ELF toolchains insert a "[build id][buildid]" into the ELF headers that typically
/// contains a hash of some ELF headers and sections to uniquely identify a binary. The Build ID
/// is allowed to be an arbitrary number of bytes however, and [GNU binutils allows creating
/// ELF binaries with Build IDs of various formats][binutils].
///
/// [buildid]: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/developer_guide/compiling-build-id
/// [binutils]: https://sourceware.org/binutils/docs-2.26/ld/Options.html#index-g_t_002d_002dbuild_002did-292
#[derive(Debug, Clone)]
pub struct CV_INFO_ELF {
    /// This will always be [`CvSignature::Elf`]
    pub cv_signature: u32,
    /// The build id, a variable number of bytes
    pub build_id: Vec<u8>,
}

impl<'a> scroll::ctx::TryFromCtx<'a, Endian> for CV_INFO_ELF {
    type Error = scroll::Error;

    fn try_from_ctx(src: &'a [u8], endian: Endian) -> Result<(Self, usize), Self::Error> {
        let offset = &mut 0;
        Ok((
            CV_INFO_ELF {
                cv_signature: src.gread_with(offset, endian)?,
                build_id: {
                    let size = src.len() - *offset;
                    src.gread_with::<&[u8]>(offset, size)?.to_owned()
                },
            },
            *offset,
        ))
    }
}

/// Obsolete debug record type defined in WinNT.h.
#[derive(Debug, Clone, Pread, SizeWith)]
pub struct IMAGE_DEBUG_MISC {
    pub data_type: u32,
    pub length: u32,
    pub unicode: u8,
    pub reserved: [u8; 3],
    pub data: [u8; 1],
}

/// Information about a single thread from a minidump
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_thread
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_THREAD {
    /// The identifier of this thread
    pub thread_id: u32,
    /// The suspend count for this thread
    ///
    /// If greater than zero, the thread is suspended.
    pub suspend_count: u32,
    /// The priority class of the thread
    ///
    /// See [Scheduling Priorities][msdn] on MSDN.
    ///
    /// [msdn]: https://docs.microsoft.com/en-us/windows/win32/ProcThread/scheduling-priorities
    pub priority_class: u32,
    /// The priority level of the thread
    pub priority: u32,
    /// The thread environment block
    pub teb: u64,
    /// The location and base address of this thread's stack memory
    pub stack: MINIDUMP_MEMORY_DESCRIPTOR,
    /// The location of a CPU-specific `CONTEXT_` struct for this thread's CPU context
    pub thread_context: MINIDUMP_LOCATION_DESCRIPTOR,
}

/// Information about the exception that caused the process to terminate.
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_exception_stream
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_EXCEPTION_STREAM {
    /// The identifier of the thread that encountered the exception.
    pub thread_id: u32,
    pub __align: u32,
    /// Detailed information about the exception encountered.
    pub exception_record: MINIDUMP_EXCEPTION,
    /// The offset of a CPU context record from the time the thread encountered the exception.
    ///
    /// The actual data will be one of the `CONTEXT_*` structs defined here.
    pub thread_context: MINIDUMP_LOCATION_DESCRIPTOR,
}

/// Detailed information about an exception.
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_exception
#[derive(Debug, Clone, Default, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_EXCEPTION {
    /// The reason the exception occurred.
    ///
    /// Possible values are in the following enums:
    ///
    /// * [`ExceptionCodeWindows`](crate::errors::ExceptionCodeWindows)
    /// * [`WinErrorWindows`](crate::errors::WinErrorWindows)
    /// * [`NtStatusWindows`](crate::errors::NtStatusWindows)
    /// * [`ExceptionCodeLinux`](crate::errors::ExceptionCodeLinux)
    /// * [`ExceptionCodeMac`](crate::errors::ExceptionCodeMac)
    pub exception_code: u32,
    /// Flags related to the exception.
    ///
    /// On Windows this is 1 for noncontinuable exceptions and 0 otherwise. For Breakpad-produced
    /// minidumps on macOS this field is used to store additional exception information.
    pub exception_flags: u32,
    /// The address of an associated [`MINIDUMP_EXCEPTION`] for a nested exception.
    ///
    /// This address is in the minidump producing host's memory.
    pub exception_record: u64,
    /// The address where the exception occurred.
    ///
    /// For Breakpad-produced minidumps on macOS this is the exception subcode, which is
    /// typically the address.
    pub exception_address: u64,
    /// The number of valid elements in [`MINIDUMP_EXCEPTION::exception_information`].
    pub number_parameters: u32,
    pub __align: u32,
    /// An array of additional arguments that describe the exception.
    ///
    /// For most exception codes the array elements are undefined, but for access violations
    /// the array will contain two elements: a read/write flag in the first element and
    /// the virtual address whose access caused the exception in the second element.
    pub exception_information: [u64; 15], // EXCEPTION_MAXIMUM_PARAMETERS
}

/// Valid bits in a `context_flags` for [`ContextFlagsCpu`]
pub const CONTEXT_CPU_MASK: u32 = 0xffffff00;
/// x86 and x64 contexts have this bit set in their `context_flags` when they have
/// extra XSTATE beyond the traditional context definition.
pub const CONTEXT_HAS_XSTATE: u32 = 0x00000040;

bitflags! {
    /// CPU type values in the `context_flags` member of `CONTEXT_` structs
    ///
    /// This applies to the [`CONTEXT_ARM`], [`CONTEXT_PPC`], [`CONTEXT_MIPS`],
    /// [`CONTEXT_AMD64`], [`CONTEXT_ARM64`], [`CONTEXT_PPC64`], [`CONTEXT_SPARC`] and
    /// [`CONTEXT_ARM64_OLD`] structs.
    pub struct ContextFlagsCpu: u32 {
        const CONTEXT_IA64 = 0x80000;
        /// Super-H, includes SH3, from winnt.h in the Windows CE 5.0 SDK
        const CONTEXT_SHX = 0xc0;
        /// From winnt.h in the Windows CE 5.0 SDK, no longer used
        ///
        /// Originally used by Breakpad but changed after conflicts with other context
        /// flag bits.
        const CONTEXT_ARM_OLD = 0x40;
        /// Alpha, from winnt.h in the Windows CE 5.0 SDK
        const CONTEXT_ALPHA = 0x20000;
        const CONTEXT_AMD64 = 0x100000;
        const CONTEXT_ARM = 0x40000000;
        const CONTEXT_ARM64 = 0x400000;
        const CONTEXT_ARM64_OLD = 0x80000000;
        const CONTEXT_MIPS = 0x40000;
        const CONTEXT_MIPS64 = 0x80000;
        const CONTEXT_PPC = 0x20000000;
        const CONTEXT_PPC64 = 0x1000000;
        const CONTEXT_SPARC = 0x10000000;
        const CONTEXT_X86 = 0x10000;
    }
}

impl ContextFlagsCpu {
    /// Populate a [`ContextFlagsCpu`] with valid bits from `flags`
    pub fn from_flags(flags: u32) -> ContextFlagsCpu {
        ContextFlagsCpu::from_bits_truncate(flags & CONTEXT_CPU_MASK)
    }
}

bitflags! {
    /// Flags available for use in [`CONTEXT_AMD64.context_flags`]
    pub struct ContextFlagsAmd64: u32 {
        /// SegSs, Rsp, SegCs, Rip, and EFlags
        const CONTEXT_AMD64_CONTROL = 0x00000001 | ContextFlagsCpu::CONTEXT_AMD64.bits;
        /// Rax, Rcx, Rdx, Rbx, Rbp, Rsi, Rdi, and R8-R15
        const CONTEXT_AMD64_INTEGER = 0x00000002 | ContextFlagsCpu::CONTEXT_AMD64.bits;
        /// SegDs, SegEs, SegFs, and SegGs
        const CONTEXT_AMD64_SEGMENTS = 0x00000004 | ContextFlagsCpu::CONTEXT_AMD64.bits;
        /// Xmm0-Xmm15
        const CONTEXT_AMD64_FLOATING_POINT = 0x00000008 | ContextFlagsCpu::CONTEXT_AMD64.bits;
        /// Dr0-Dr3 and Dr6-Dr7
        const CONTEXT_AMD64_DEBUG_REGISTERS = 0x00000010 | ContextFlagsCpu::CONTEXT_AMD64.bits;
        const CONTEXT_AMD64_XSTATE = 0x00000020 | ContextFlagsCpu::CONTEXT_AMD64.bits;
        const CONTEXT_AMD64_FULL = Self::CONTEXT_AMD64_CONTROL.bits | Self::CONTEXT_AMD64_INTEGER.bits | Self::CONTEXT_AMD64_FLOATING_POINT.bits;
        const CONTEXT_AMD64_ALL = Self::CONTEXT_AMD64_FULL.bits | Self::CONTEXT_AMD64_SEGMENTS.bits | Self::CONTEXT_AMD64_DEBUG_REGISTERS.bits;
    }
}

bitflags! {
    /// Flags available for use in [`CONTEXT_X86.context_flags`]
    pub struct ContextFlagsX86: u32 {
        /// Ebp, Eip, SegCs, EFlags, Esp, SegSs
        const CONTEXT_X86_CONTROL = 0x00000001 | ContextFlagsCpu::CONTEXT_X86.bits;
        /// Edi, Esi, Ebx, Edx, Ecx, Eax
        const CONTEXT_X86_INTEGER = 0x00000002 | ContextFlagsCpu::CONTEXT_X86.bits;
        /// SegDs, SegEs, SegFs, and SegGs
        const CONTEXT_X86_SEGMENTS = 0x00000004 | ContextFlagsCpu::CONTEXT_X86.bits;
        /// Fpcr, Fpsr, Fptag, Fpioff, Fpisel, Fpdoff, Fpdsel, Mxcsr, Mxcsr_mask, Xmm0-Xmm7
        const CONTEXT_X86_FLOATING_POINT = 0x00000008 | ContextFlagsCpu::CONTEXT_X86.bits;
        /// Dr0-Dr3 and Dr6-Dr7
        const CONTEXT_X86_DEBUG_REGISTERS = 0x00000010 | ContextFlagsCpu::CONTEXT_X86.bits;
        const CONTEXT_X86_EXTENDED_REGISTERS = 0x00000020 | ContextFlagsCpu::CONTEXT_X86.bits;
        const CONTEXT_X86_XSTATE = 0x00000040 | ContextFlagsCpu::CONTEXT_X86.bits;
        const CONTEXT_X86_FULL = Self::CONTEXT_X86_CONTROL.bits | Self::CONTEXT_X86_INTEGER.bits | Self::CONTEXT_X86_SEGMENTS.bits;
        const CONTEXT_X86_ALL = Self::CONTEXT_X86_FULL.bits | Self::CONTEXT_X86_FLOATING_POINT.bits | Self::CONTEXT_X86_DEBUG_REGISTERS.bits | Self::CONTEXT_X86_EXTENDED_REGISTERS.bits;
    }
}

bitflags! {
    /// Flags available for use in [`CONTEXT_ARM64.context_flags`]
    pub struct ContextFlagsArm64: u32 {
        /// FP, LR, SP, PC, and CPSR
        const CONTEXT_ARM64_CONTROL = 0x00000001 | ContextFlagsCpu::CONTEXT_ARM64.bits;
        /// X0-X28 (but maybe not X18)
        const CONTEXT_ARM64_INTEGER = 0x00000002 | ContextFlagsCpu::CONTEXT_ARM64.bits;
        /// Fpcr, Fpsr, D0-D31 (AKA Q0-Q31, AKA S0-S31)
        const CONTEXT_ARM64_FLOATING_POINT = 0x00000004 | ContextFlagsCpu::CONTEXT_ARM64.bits;
        /// DBGBVR, DBGBCR, DBGWVR, DBGWCR
        const CONTEXT_ARM64_DEBUG_REGISTERS = 0x0000008 | ContextFlagsCpu::CONTEXT_ARM64.bits;
        /// Whether x18 has a valid value, because on Windows it contains the TEB.
        ///
        /// NOTE: at this precise moment breakpad doesn't define this, but Microsoft does!
        const CONTEXT_ARM64_X18 = 0x0000010 | ContextFlagsCpu::CONTEXT_ARM64.bits;
        const CONTEXT_ARM64_FULL = Self::CONTEXT_ARM64_CONTROL.bits | Self::CONTEXT_ARM64_INTEGER.bits | Self::CONTEXT_ARM64_FLOATING_POINT.bits;
        const CONTEXT_ARM64_ALL = Self::CONTEXT_ARM64_FULL.bits | Self::CONTEXT_ARM64_DEBUG_REGISTERS.bits | Self::CONTEXT_ARM64_X18.bits;
    }
}

bitflags! {
    /// Flags available for use in [`CONTEXT_ARM64_OLD.context_flags`]
    pub struct ContextFlagsArm64Old: u32 {
        // Yes, breakpad never defined CONTROL for this context

        /// FP, LR, SP, PC, CPSR, and X0-X28
        const CONTEXT_ARM64_OLD_INTEGER = 0x00000002 | ContextFlagsCpu::CONTEXT_ARM64_OLD.bits;
        /// Fpcr, Fpsr, D0-D31 (AKA Q0-Q31, AKA S0-S31)
        const CONTEXT_ARM64_OLD_FLOATING_POINT = 0x00000004 | ContextFlagsCpu::CONTEXT_ARM64_OLD.bits;
        const CONTEXT_ARM64_OLD_FULL = Self::CONTEXT_ARM64_OLD_INTEGER.bits | Self::CONTEXT_ARM64_OLD_FLOATING_POINT.bits;
        const CONTEXT_ARM64_OLD_ALL = Self::CONTEXT_ARM64_OLD_FULL.bits;
    }
}

bitflags! {
    /// Flags available for use in [`CONTEXT_ARM.context_flags`]
    pub struct ContextFlagsArm: u32 {
        // Yes, breakpad never defined CONTROL for this context

        /// SP, LR, PC, and CPSR
        const CONTEXT_ARM_CONTROL = 0x00000001 | ContextFlagsCpu::CONTEXT_ARM.bits;
        /// R0-R12
        const CONTEXT_ARM_INTEGER = 0x00000002 | ContextFlagsCpu::CONTEXT_ARM.bits;
        /// Q0-Q15 / D0-D31 / S0-S31
        const CONTEXT_ARM_FLOATING_POINT = 0x00000004 | ContextFlagsCpu::CONTEXT_ARM.bits;
        /// DBGBVR, DBGBCR, DBGWVR, DBGWCR
        const CONTEXT_ARM_DEBUG_REGISTERS = 0x00000008 | ContextFlagsCpu::CONTEXT_ARM.bits;
        const CONTEXT_ARM_FULL = Self::CONTEXT_ARM_CONTROL.bits | Self::CONTEXT_ARM_INTEGER.bits | Self::CONTEXT_ARM_FLOATING_POINT.bits;
        const CONTEXT_ARM_ALL = Self::CONTEXT_ARM_FULL.bits | Self::CONTEXT_ARM_DEBUG_REGISTERS.bits;
    }
}

/// Possible contents of [`CONTEXT_AMD64::float_save`].
///
/// This struct matches the definition of the struct with the same name from WinNT.h.
#[derive(Debug, SmartDefault, Clone, Pread, Pwrite, SizeWith)]
pub struct XMM_SAVE_AREA32 {
    pub control_word: u16,
    pub status_word: u16,
    pub tag_word: u8,
    pub reserved1: u8,
    pub error_opcode: u16,
    pub error_offset: u32,
    pub error_selector: u16,
    pub reserved2: u16,
    pub data_offset: u32,
    pub data_selector: u16,
    pub reserved3: u16,
    pub mx_csr: u32,
    pub mx_csr_mask: u32,
    #[default([0; 8])]
    pub float_registers: [u128; 8],
    #[default([0; 16])]
    pub xmm_registers: [u128; 16],
    #[default([0; 96])]
    pub reserved4: [u8; 96],
}

/// Possible contents of [`CONTEXT_AMD64::float_save`].
///
/// This is defined as an anonymous struct inside an anonymous union in
/// the x86-64 CONTEXT struct in WinNT.h.
#[derive(Debug, Clone, Pread, SizeWith)]
pub struct SSE_REGISTERS {
    pub header: [u128; 2],
    pub legacy: [u128; 8],
    pub xmm0: u128,
    pub xmm1: u128,
    pub xmm2: u128,
    pub xmm3: u128,
    pub xmm4: u128,
    pub xmm5: u128,
    pub xmm6: u128,
    pub xmm7: u128,
    pub xmm8: u128,
    pub xmm9: u128,
    pub xmm10: u128,
    pub xmm11: u128,
    pub xmm12: u128,
    pub xmm13: u128,
    pub xmm14: u128,
    pub xmm15: u128,
}

/// An x86-64 (amd64) CPU context
///
/// This struct matches the definition of `CONTEXT` in WinNT.h for x86-64.
#[derive(Debug, SmartDefault, Clone, Pread, Pwrite, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct CONTEXT_AMD64 {
    pub p1_home: u64,
    pub p2_home: u64,
    pub p3_home: u64,
    pub p4_home: u64,
    pub p5_home: u64,
    pub p6_home: u64,
    pub context_flags: u32,
    pub mx_csr: u32,
    pub cs: u16,
    pub ds: u16,
    pub es: u16,
    pub fs: u16,
    pub gs: u16,
    pub ss: u16,
    pub eflags: u32,
    pub dr0: u64,
    pub dr1: u64,
    pub dr2: u64,
    pub dr3: u64,
    pub dr6: u64,
    pub dr7: u64,
    pub rax: u64,
    pub rcx: u64,
    pub rdx: u64,
    pub rbx: u64,
    pub rsp: u64,
    pub rbp: u64,
    pub rsi: u64,
    pub rdi: u64,
    pub r8: u64,
    pub r9: u64,
    pub r10: u64,
    pub r11: u64,
    pub r12: u64,
    pub r13: u64,
    pub r14: u64,
    pub r15: u64,
    pub rip: u64,
    /// Floating point state
    ///
    /// This is defined as a union in the C headers, but also
    /// ` MAXIMUM_SUPPORTED_EXTENSION` is defined as 512 bytes.
    ///
    /// Callers that want to access the underlying data can use [`Pread`] to read either
    /// an [`XMM_SAVE_AREA32`] or [`SSE_REGISTERS`] struct from this raw data as appropriate.
    #[default([0; 512])]
    pub float_save: [u8; 512],
    #[default([0; 26])]
    pub vector_register: [u128; 26],
    pub vector_control: u64,
    pub debug_control: u64,
    pub last_branch_to_rip: u64,
    pub last_branch_from_rip: u64,
    pub last_exception_to_rip: u64,
    pub last_exception_from_rip: u64,
}

/// ARM floating point state
#[derive(Debug, Clone, Default, Pread, Pwrite, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct FLOATING_SAVE_AREA_ARM {
    pub fpscr: u64,
    pub regs: [u64; 32],
    pub extra: [u32; 8],
}

/// An ARM CPU context
///
/// This is a Breakpad extension, and does not match the definition of `CONTEXT` for ARM
/// in WinNT.h.
#[derive(Debug, Clone, Default, Pread, Pwrite, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct CONTEXT_ARM {
    pub context_flags: u32,
    // [r0, r1, ..., r15]
    pub iregs: [u32; 16],
    pub cpsr: u32,
    pub float_save: FLOATING_SAVE_AREA_ARM,
}

/// Offsets into [`CONTEXT_ARM::iregs`] for registers with a dedicated or conventional purpose
#[repr(usize)]
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum ArmRegisterNumbers {
    IosFramePointer = 7,
    FramePointer = 11,
    StackPointer = 13,
    LinkRegister = 14,
    ProgramCounter = 15,
}

impl ArmRegisterNumbers {
    pub const fn name(self) -> &'static str {
        match self {
            Self::IosFramePointer => "r7",
            Self::FramePointer => "r11",
            Self::StackPointer => "r13",
            Self::LinkRegister => "r14",
            Self::ProgramCounter => "r15",
        }
    }
}

/// An old (breakpad-style) aarch64 (arm64) CPU context.
///
/// This is a breakpad extension, but contrary to what the name might suggest,
/// it isn't completely out of service. I believe all non-windows platforms
/// still prefer emitting this format to avoid needless churn.
///
/// Semantically this type agrees with the "new" [CONTEXT_ARM64][] and can
/// generally be handled with all the same logic. i.e. the general purpose
/// `iregs` are the same. It's just that the other fields are shuffled around.
///
/// As I understand it, this is basically an artifact of breakpad getting to
/// arm64 "first" (Android would be first in line for it!) and picking a
/// definition they thought was reasonable. Thankfully they picked an
/// "out of the way" context id so that when Microsoft came along and picked
/// their own definition, there wouldn't be a conflict.
///
/// Note that we have inlined the fields of the "float save" struct from
/// breakpad's definition to be more uniform with [CONTEXT_ARM64][].
///
/// NOTE: if you ever decide to try to make this repr(C) and get really clever,
/// this type is actually non-trivially repr(packed(4)) in the headers!
#[derive(Debug, Clone, Copy, Default, Pread, Pwrite, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct CONTEXT_ARM64_OLD {
    pub context_flags: u64,
    /// `[x0, x1, ..., x28, fp, lr]`. See [Arm64RegisterNumbers][].
    pub iregs: [u64; 31],
    pub sp: u64,
    pub pc: u64,
    pub cpsr: u32,
    /// FPU status register.
    pub fpsr: u32,
    /// FPU control register.
    pub fpcr: u32,
    /// float/NEON registers `[d0, d1, ..., d31]`
    pub float_regs: [u128; 32usize],
}

/// A (microsoft-style) aarch64 (arm64) CPU context
///
/// This matches the layout of how Windows defines this type. Breakpad defines
/// it in an equivalent but more-quirky way that relies more on packing.
///
/// For general purpose registers:
///
/// * microsoft: make iregs have 31 values and have sp and pc as explicit fields.
/// * breakpad make iregs have 33 values, no explicit fields.
///
/// For float registers:
///
/// * microsoft: inline the fields for float_regs, fpcr, fpsr.
/// * breakpad: wrap them in a struct.
///
/// -----------------
///
/// Why *we* went with these definitions:
///
/// * ARM64 actually defines x0..x30 register names, but sp and pc aren't
///   "x31" and "x32". Breakpad is effectively punning them as such, and
///   that's kinda weird?
///
/// * Microsft's inlining of the float registers eliminates any need for
///   padding on all platforms (note how there's always an even number of
///   u32's before a u64, and an even number of u64's before a u128!)
///
/// NOTE: if you ever decide to try to make this repr(C) and get really clever,
/// note that microsoft aligns this to 16 (and as of this writing, rust does
/// not consistently aling u128 as such).
#[derive(Debug, Default, Clone, Pread, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct CONTEXT_ARM64 {
    pub context_flags: u32,
    pub cpsr: u32,
    /// `[x0, x1, ..., x28, fp, lr]`. See [Arm64RegisterNumbers][].
    pub iregs: [u64; 31],
    pub sp: u64,
    pub pc: u64,
    /// float/NEON registers `[d0, d1, ..., d31]`
    pub float_regs: [u128; 32usize],
    /// FPU control register.
    pub fpcr: u32,
    /// FPU status register.
    pub fpsr: u32,
    pub bcr: [u32; 8],
    pub bvr: [u64; 8],
    pub wcr: [u32; 2],
    pub wvr: [u64; 2],
}

/// Offsets into [`CONTEXT_ARM64::iregs`] for registers with a dedicated or conventional purpose
#[repr(usize)]
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum Arm64RegisterNumbers {
    FramePointer = 29,
    LinkRegister = 30,
}

impl Arm64RegisterNumbers {
    pub const fn name(self) -> &'static str {
        match self {
            Self::FramePointer => "x29",
            Self::LinkRegister => "x30",
        }
    }
}

/// MIPS floating point state
#[derive(Debug, Default, Clone, Pread, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct FLOATING_SAVE_AREA_MIPS {
    pub regs: [u64; 32],
    pub fpcsr: u32,
    pub fir: u32,
}

/// A MIPS CPU context
///
/// This is a Breakpad extension, as there is no definition of `CONTEXT` for MIPS in WinNT.h.
#[derive(Debug, Default, Clone, Pread, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct CONTEXT_MIPS {
    pub context_flags: u32,
    pub _pad0: u32,
    pub iregs: [u64; 32],
    pub mdhi: u64,
    pub mdlo: u64,
    pub hi: [u32; 3],
    pub lo: [u32; 3],
    pub dsp_control: u32,
    pub _pad1: u32,
    pub epc: u64,
    pub badvaddr: u64,
    pub status: u32,
    pub cause: u32,
    pub float_save: FLOATING_SAVE_AREA_MIPS,
}

/// Offsets into [`CONTEXT_MIPS::iregs`] for registers with a dedicated or conventional purpose
#[repr(usize)]
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum MipsRegisterNumbers {
    S0 = 16,
    S1 = 17,
    S2 = 18,
    S3 = 19,
    S4 = 20,
    S5 = 21,
    S6 = 22,
    S7 = 23,
    GlobalPointer = 28,
    StackPointer = 29,
    FramePointer = 30,
    ReturnAddress = 31,
}

impl MipsRegisterNumbers {
    pub const fn name(self) -> &'static str {
        match self {
            MipsRegisterNumbers::S0 => "s0",
            MipsRegisterNumbers::S1 => "s1",
            MipsRegisterNumbers::S2 => "s2",
            MipsRegisterNumbers::S3 => "s3",
            MipsRegisterNumbers::S4 => "s4",
            MipsRegisterNumbers::S5 => "s5",
            MipsRegisterNumbers::S6 => "s6",
            MipsRegisterNumbers::S7 => "s7",
            MipsRegisterNumbers::GlobalPointer => "gp",
            MipsRegisterNumbers::StackPointer => "sp",
            MipsRegisterNumbers::FramePointer => "fp",
            MipsRegisterNumbers::ReturnAddress => "ra",
        }
    }
}

/// PPC floating point state
#[derive(Debug, Clone, Pread, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct FLOATING_SAVE_AREA_PPC {
    pub fpregs: [u64; 32],
    pub fpscr_pad: u32,
    pub fpscr: u32,
}

/// PPC vector state
#[derive(Debug, Clone, Pread, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct VECTOR_SAVE_AREA_PPC {
    pub save_vr: [u128; 32],
    pub save_vscr: u128,
    pub save_pad5: [u32; 4],
    pub save_vrvalid: u32,
    pub save_pad6: [u32; 7],
}

/// A PPC CPU context
///
/// This is a Breakpad extension, as there is no definition of `CONTEXT` for PPC in WinNT.h.
#[derive(Debug, Clone, Pread, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct CONTEXT_PPC {
    pub context_flags: u32,
    pub srr0: u32,
    pub srr1: u32,
    pub gpr: [u32; 32],
    pub cr: u32,
    pub xer: u32,
    pub lr: u32,
    pub ctr: u32,
    pub mq: u32,
    pub vrsave: u32,
    pub float_save: FLOATING_SAVE_AREA_PPC,
    pub vector_save: VECTOR_SAVE_AREA_PPC,
}

/// Offsets into [`CONTEXT_PPC::gpr`] for registers with a dedicated or conventional purpose
#[repr(usize)]
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum PpcRegisterNumbers {
    StackPointer = 1,
}

/// A PPC64 CPU context
///
/// This is a Breakpad extension, as there is no definition of `CONTEXT` for PPC64 in WinNT.h.
#[derive(Debug, Clone, Pread, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct CONTEXT_PPC64 {
    pub context_flags: u64,
    pub srr0: u64,
    pub srr1: u64,
    pub gpr: [u64; 32],
    pub cr: u64,
    pub xer: u64,
    pub lr: u64,
    pub ctr: u64,
    pub vrsave: u64,
    pub float_save: FLOATING_SAVE_AREA_PPC,
    pub vector_save: VECTOR_SAVE_AREA_PPC,
}

/// Offsets into [`CONTEXT_PPC64::gpr`] for registers with a dedicated or conventional purpose
#[repr(usize)]
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum Ppc64RegisterNumbers {
    StackPointer = 1,
}

/// SPARC floating point state
#[derive(Debug, Clone, Pread, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct FLOATING_SAVE_AREA_SPARC {
    pub regs: [u64; 32],
    pub filler: u64,
    pub fsr: u64,
}

/// A SPARC CPU context
///
/// This is a Breakpad extension, as there is no definition of `CONTEXT` for SPARC in WinNT.h.
#[derive(Debug, Clone, Pread, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct CONTEXT_SPARC {
    pub context_flags: u32,
    pub flag_pad: u32,
    pub g_r: [u64; 32],
    pub ccr: u64,
    pub pc: u64,
    pub npc: u64,
    pub y: u64,
    pub asi: u64,
    pub fprs: u64,
    pub float_save: FLOATING_SAVE_AREA_SPARC,
}

/// Offsets into [`CONTEXT_SPARC::g_r`] for registers with a dedicated or conventional purpose
#[repr(usize)]
#[derive(Copy, Clone, PartialEq, Eq, Debug)]
pub enum SparcRegisterNumbers {
    StackPointer = 14,
}

/// x86 floating point state
///
/// This struct matches the definition of the `FLOATING_SAVE_AREA` struct from WinNT.h.
#[derive(Debug, Clone, SmartDefault, Pread, Pwrite, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct FLOATING_SAVE_AREA_X86 {
    pub control_word: u32,
    pub status_word: u32,
    pub tag_word: u32,
    pub error_offset: u32,
    pub error_selector: u32,
    pub data_offset: u32,
    pub data_selector: u32,
    #[default([0; 80])]
    pub register_area: [u8; 80], // SIZE_OF_80387_REGISTERS
    pub cr0_npx_state: u32,
}

/// An x86 CPU context
///
/// This struct matches the definition of `CONTEXT` in WinNT.h for x86.
#[derive(Debug, Clone, SmartDefault, Pread, Pwrite, SizeWith)]
#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
pub struct CONTEXT_X86 {
    pub context_flags: u32,
    pub dr0: u32,
    pub dr1: u32,
    pub dr2: u32,
    pub dr3: u32,
    pub dr6: u32,
    pub dr7: u32,
    pub float_save: FLOATING_SAVE_AREA_X86,
    pub gs: u32,
    pub fs: u32,
    pub es: u32,
    pub ds: u32,
    pub edi: u32,
    pub esi: u32,
    pub ebx: u32,
    pub edx: u32,
    pub ecx: u32,
    pub eax: u32,
    pub ebp: u32,
    pub eip: u32,
    pub cs: u32,
    pub eflags: u32,
    pub esp: u32,
    pub ss: u32,
    #[default([0; 512])]
    pub extended_registers: [u8; 512], // MAXIMUM_SUPPORTED_EXTENSION
}

/// CPU information contained within the [`MINIDUMP_SYSTEM_INFO`] struct
///
/// This struct matches the definition of the `CPU_INFORMATION` union from minidumpapiset.h.
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct CPU_INFORMATION {
    /// `data` is defined as a union in the Microsoft headers
    ///
    /// It is the union of [`X86CpuInfo`], [`ARMCpuInfo`] (Breakpad-specific), and
    /// [`OtherCpuInfo`] defined below. It does not seem possible to safely derive [`Pread`]
    /// on an actual union, so we provide the raw data here and expect callers to use
    /// [`Pread`] to derive the specific union representation desired.
    pub data: [u8; 24],
}

/// x86-specific CPU information derived from the `cpuid` instruction
///
/// This struct matches the definition of the struct of the same name from minidumpapiset.h,
/// which is contained within the [`CPU_INFORMATION`] union.
#[derive(Debug, Clone, Pread, SizeWith)]
pub struct X86CpuInfo {
    pub vendor_id: [u32; 3],
    pub version_information: u32,
    pub feature_information: u32,
    pub amd_extended_cpu_features: u32,
}

/// Arm-specific CPU information (Breakpad extension)
#[derive(Debug, Clone, Pread, SizeWith)]
pub struct ARMCpuInfo {
    pub cpuid: u32,
    /// Hardware capabilities
    ///
    /// See [`ArmElfHwCaps`] for possible values.
    pub elf_hwcaps: u32,
}

/// CPU information for non-x86 CPUs
///
/// This struct matches the definition of the struct of the same name from minidumpapiset.h,
/// which is contained within the [`CPU_INFORMATION`] union.
#[derive(Debug, Clone, Pread, SizeWith)]
pub struct OtherCpuInfo {
    pub processor_features: [u64; 2],
}

/// Processor and operating system information
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_system_info
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_SYSTEM_INFO {
    /// The system's processor architecture
    ///
    /// Known values are defined in [`ProcessorArchitecture`].
    pub processor_architecture: u16,
    /// x86 (5 = 586, 6 = 686 ...) or ARM (6 = ARMv6, 7 = ARMv7 ...) CPU level
    pub processor_level: u16,
    /// For x86, 0xMMSS where MM=model, SS=stepping
    pub processor_revision: u16,
    pub number_of_processors: u8,
    pub product_type: u8,
    pub major_version: u32,
    pub minor_version: u32,
    pub build_number: u32,
    /// The operating system platform
    ///
    /// Known values are defined in [`PlatformId`].
    pub platform_id: u32,
    pub csd_version_rva: RVA,
    pub suite_mask: u16,
    pub reserved2: u16,
    pub cpu: CPU_INFORMATION,
}

/// Known values of [`MINIDUMP_SYSTEM_INFO::processor_architecture`]
///
/// Many of these are taken from definitions in WinNT.h, but several of them are
/// Breakpad extensions.
#[repr(u16)]
#[derive(Copy, Clone, PartialEq, Eq, Debug, Primitive)]
pub enum ProcessorArchitecture {
    PROCESSOR_ARCHITECTURE_INTEL = 0,
    PROCESSOR_ARCHITECTURE_MIPS = 1,
    PROCESSOR_ARCHITECTURE_ALPHA = 2,
    PROCESSOR_ARCHITECTURE_PPC = 3,
    PROCESSOR_ARCHITECTURE_SHX = 4,
    PROCESSOR_ARCHITECTURE_ARM = 5,
    PROCESSOR_ARCHITECTURE_IA64 = 6,
    PROCESSOR_ARCHITECTURE_ALPHA64 = 7,
    /// Microsoft Intermediate Language
    PROCESSOR_ARCHITECTURE_MSIL = 8,
    PROCESSOR_ARCHITECTURE_AMD64 = 9,
    /// WoW64
    PROCESSOR_ARCHITECTURE_IA32_ON_WIN64 = 10,
    PROCESSOR_ARCHITECTURE_ARM64 = 12,
    /// Breakpad-defined value for SPARC
    PROCESSOR_ARCHITECTURE_SPARC = 0x8001,
    /// Breakpad-defined value for PPC64
    PROCESSOR_ARCHITECTURE_PPC64 = 0x8002,
    /// Breakpad-defined value for ARM64
    PROCESSOR_ARCHITECTURE_ARM64_OLD = 0x8003,
    /// Breakpad-defined value for MIPS64
    PROCESSOR_ARCHITECTURE_MIPS64 = 0x8004,
    PROCESSOR_ARCHITECTURE_UNKNOWN = 0xffff,
}

/// Known values of [`MINIDUMP_SYSTEM_INFO::platform_id`]
///
/// The Windows values here are taken from defines in WinNT.h, but the rest are Breakpad
/// extensions.
#[repr(u32)]
#[derive(Copy, Clone, PartialEq, Eq, Debug, Primitive)]
pub enum PlatformId {
    /// Windows 3.1
    VER_PLATFORM_WIN32s = 1,
    /// Windows 95-98-Me
    VER_PLATFORM_WIN32_WINDOWS = 2,
    /// Windows NT, 2000+
    VER_PLATFORM_WIN32_NT = 3,
    /// Windows CE, Windows Mobile
    VER_PLATFORM_WIN32_CE = 4,
    /// Generic Unix-ish (Breakpad extension)
    Unix = 0x8000,
    /// macOS/Darwin (Breakpad extension)
    MacOs = 0x8101,
    /// iOS (Breakpad extension)
    Ios = 0x8102,
    /// Linux (Breakpad extension)
    Linux = 0x8201,
    /// Solaris (Breakpad extension)
    Solaris = 0x8202,
    /// Android (Breakpad extension)
    Android = 0x8203,
    /// PlayStation 3 (Breakpad extension)
    Ps3 = 0x8204,
    /// Native Client (Breakpad extension)
    NaCl = 0x8205,
}

/// A date and time
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://msdn.microsoft.com/en-us/library/windows/desktop/ms724950(v=vs.85).aspx
#[derive(Debug, Clone, Default, Pread, Pwrite, SizeWith, PartialEq, Eq)]
pub struct SYSTEMTIME {
    pub year: u16,
    pub month: u16,
    pub day_of_week: u16,
    pub day: u16,
    pub hour: u16,
    pub minute: u16,
    pub second: u16,
    pub milliseconds: u16,
}

/// Settings for a time zone
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/timezoneapi/ns-timezoneapi-time_zone_information
#[derive(Debug, Clone, Default, Pread, Pwrite, SizeWith)]
pub struct TIME_ZONE_INFORMATION {
    pub bias: i32,
    pub standard_name: [u16; 32],
    pub standard_date: SYSTEMTIME,
    pub standard_bias: i32,
    pub daylight_name: [u16; 32],
    pub daylight_date: SYSTEMTIME,
    pub daylight_bias: i32,
}

/*
 * There are multiple versions of the misc info struct, and each new version includes all
 * fields from the previous versions. We declare them with a macro to avoid repeating
 * the fields excessively.
 */
macro_rules! multi_structs {
    // With no trailing struct left, terminate.
    (@next { $($prev:tt)* }) => {};
    // Declare the next struct, including fields from previous structs.
    (@next { $($prev:tt)* } $(#[$attr:meta])* pub struct $name:ident { $($cur:tt)* } $($tail:tt)* ) => {
        // Prepend fields from previous structs to this struct.
        multi_structs!($(#[$attr])* pub struct $name { $($prev)* $($cur)* } $($tail)*);
    };
    // Declare a single struct.
    ($(#[$attr:meta])* pub struct $name:ident { $( pub $field:ident: $t:tt, )* } $($tail:tt)* ) => {
        $(#[$attr])*
        #[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
        pub struct $name {
            $( pub $field: $t, )*
        }
        // Persist its fields down to the following structs.
        multi_structs!(@next { $( pub $field: $t, )* } $($tail)*);
    };
}

multi_structs! {
    /// Miscellaneous process information
    ///
    /// This struct matches the [Microsoft struct][msdn] of the same name.
    ///
    /// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_misc_info
    pub struct MINIDUMP_MISC_INFO {
        pub size_of_info: u32,
        pub flags1: u32,
        pub process_id: u32,
        pub process_create_time: u32,
        pub process_user_time: u32,
        pub process_kernel_time: u32,
    }
    // Includes fields from MINIDUMP_MISC_INFO
    /// Miscellaneous process and system information
    ///
    /// This struct matches the [Microsoft struct][msdn] of the same name.
    ///
    /// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_misc_info_2
    pub struct MINIDUMP_MISC_INFO_2 {
        pub processor_max_mhz: u32,
        pub processor_current_mhz: u32,
        pub processor_mhz_limit: u32,
        pub processor_max_idle_state: u32,
        pub processor_current_idle_state: u32,
    }
    // Includes fields from MINIDUMP_MISC_INFO and MINIDUMP_MISC_INFO_2
    /// Miscellaneous process and system information
    ///
    /// This struct matches the struct of the same name from minidumpapiset.h.
    pub struct MINIDUMP_MISC_INFO_3 {
        pub process_integrity_level: u32,
        pub process_execute_flags: u32,
        pub protected_process: u32,
        pub time_zone_id: u32,
        pub time_zone: TIME_ZONE_INFORMATION,
    }
    // Includes fields from MINIDUMP_MISC_INFO..3
    /// Miscellaneous process and system information
    ///
    /// This struct matches the struct of the same name from minidumpapiset.h.
    pub struct MINIDUMP_MISC_INFO_4 {
        pub build_string: [u16; 260], // MAX_PATH
        pub dbg_bld_str: [u16; 40],
    }

    // Includes fields from MINIDUMP_MISC_INFO..4
    /// Miscellaneous process and system information
    ///
    /// This struct matches the struct of the same name from minidumpapiset.h.
    pub struct MINIDUMP_MISC_INFO_5 {
        pub xstate_data: XSTATE_CONFIG_FEATURE_MSC_INFO,
        pub process_cookie: u32,
    }
}

/// A descriptor of the XSAVE context, which extends a normal x86/x64 context.
///
/// The sections of this context are dumps of some of the CPUs registers
/// (e.g. one section might contain the contents of the SSE registers).
///
/// Intel documents its XSAVE entries in Volume 1, Chapter 13 of the
/// "Intel 64 and IA-32 Architectures Software Developer’s Manual".
///
///
/// # The XSTATE Format in Minidumps
///
/// This format is slightly messed up in the context of minidumps because it's
/// grafted onto Microsoft's own formats. Here's what's important to know:
///
/// * The "Cpu Context" and the "XSAVE context" are in fact the same regions
/// of memory.
///
/// * Whether XSTATE is present or not, the classic layouts of CONTEXT_X86
/// and [`CONTEXT_AMD64`] both apply -- xstate will only add stuff after *or*
/// refine your understanding of memory in the existing layout. So you can
/// safely ignore the existence of XSTATE, but you might be missing new info.
///
/// * AMD64 doesn't have a standard way to save general purpose registers,
/// so the first 256 bytes of [`CONTEXT_AMD64`] are just however microsoft
/// decided to save the registers, and will not be referred to by the XSTATE.
///
/// **!!! THIS PART IS IMPORTANT !!!**
///
/// * As a consequence, all [`XSTATE_FEATURE::offset`] values must have 256
/// added to them to get the correct offset for that feature! For example, the
/// LEGACY_FLOATING_POINT feature should always have an offset of 0, but it
/// is actually at offset 256 in [`CONTEXT_AMD64`] (it corresponds to
/// [`CONTEXT_AMD64::float_save`]).
///
/// * The following features are already contained inside of [`CONTEXT_AMD64`]:
///    * LEGACY_FLOATING_POINT
///    * LEGACY_SSE
///    * GSSE_AND_AVX
///
/// * If there are XSTATE entries that *actually* map outside of the context's
/// normal memory range, then the context's [`context_flags`](`CONTEXT_AMD64::context_flags`)
/// will have bit 0x40 set ([`CONTEXT_HAS_XSTATE`]).
///
/// * [`ContextFlagsCpu::from_flags`] will mask out the [`CONTEXT_HAS_XSTATE`] bit.
/// If you want to check for that bit, check the raw value of
/// [`context_flags`](`CONTEXT_AMD64::context_flags`).

#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct XSTATE_CONFIG_FEATURE_MSC_INFO {
    /// The size of this struct.
    pub size_of_info: u32,
    /// The size of the XSAVE context.
    pub context_size: u32,
    /// The bit `enabled_features[i]` indicates that `features[i]` contains valid data.
    pub enabled_features: u64,
    /// The offset and size of each XSAVE entry inside the XSAVE context.
    pub features: [XSTATE_FEATURE; 64],
}

impl Default for XSTATE_CONFIG_FEATURE_MSC_INFO {
    fn default() -> Self {
        Self {
            size_of_info: std::mem::size_of::<XSTATE_CONFIG_FEATURE_MSC_INFO>() as u32,
            context_size: 0,
            enabled_features: 0,
            features: [XSTATE_FEATURE::default(); 64],
        }
    }
}

impl XSTATE_CONFIG_FEATURE_MSC_INFO {
    /// Gets an iterator of all the enabled features.
    pub fn iter(&self) -> XstateFeatureIter {
        XstateFeatureIter { info: self, idx: 0 }
    }
}

/// An iterator of all the enabled features in an XSTATE_CONFIG_FEATURE_MSC_INFO.
#[derive(Debug)]
pub struct XstateFeatureIter<'a> {
    info: &'a XSTATE_CONFIG_FEATURE_MSC_INFO,
    idx: usize,
}

impl<'a> Iterator for XstateFeatureIter<'a> {
    type Item = (usize, XSTATE_FEATURE);
    fn next(&mut self) -> Option<Self::Item> {
        while self.idx < self.info.features.len() {
            let cur_idx = self.idx;
            self.idx += 1;
            if (self.info.enabled_features & (1 << cur_idx)) != 0 {
                return Some((cur_idx, self.info.features[cur_idx]));
            }
        }
        None
    }
}

/// Several known entries in `XSTATE_CONFIG_FEATURE_MSC_INFO.features`.
#[repr(usize)]
#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
pub enum XstateFeatureIndex {
    LEGACY_FLOATING_POINT = 0,
    LEGACY_SSE = 1,
    GSSE_AND_AVX = 2,
    MPX_BNDREGS = 3,
    MPX_BNDCSR = 4,
    AVX512_KMASK = 5,
    AVX512_ZMM_H = 6,
    ACK512_ZMM = 7,
    XSTATE_IPT = 8,
    XSTATE_LWP = 62,
}

impl XstateFeatureIndex {
    pub fn from_index(idx: usize) -> Option<Self> {
        use XstateFeatureIndex::*;
        match idx {
            0 => Some(LEGACY_FLOATING_POINT),
            1 => Some(LEGACY_SSE),
            2 => Some(GSSE_AND_AVX),
            3 => Some(MPX_BNDREGS),
            4 => Some(MPX_BNDCSR),
            5 => Some(AVX512_KMASK),
            6 => Some(AVX512_ZMM_H),
            7 => Some(ACK512_ZMM),
            8 => Some(XSTATE_IPT),
            62 => Some(XSTATE_LWP),
            _ => None,
        }
    }
}

/// The offset and size of each XSAVE entry inside the XSAVE context.
#[derive(Clone, Copy, Debug, Default, Pread, Pwrite, SizeWith, PartialEq, Eq)]
pub struct XSTATE_FEATURE {
    /// This entry's offset from the start of the context (in bytes).
    ///
    /// NOTE: THIS VALUE IS A LIE. At least on AMD64 you need to add 256
    /// to this! See the docs of [`XSTATE_CONFIG_FEATURE_MSC_INFO`].
    pub offset: u32,
    /// This entry's size (in bytes).
    pub size: u32,
}

// For whatever reason Pread array derives use 0u8.into() instead of Default to
// create an initial array to write into. Weird.
impl From<u8> for XSTATE_FEATURE {
    fn from(_input: u8) -> Self {
        XSTATE_FEATURE { offset: 0, size: 0 }
    }
}

bitflags! {
    /// Known flags for `MINIDUMP_MISC_INFO*.flags1`
    pub struct MiscInfoFlags: u32 {
        const MINIDUMP_MISC1_PROCESS_ID            = 0x00000001;
        const MINIDUMP_MISC1_PROCESS_TIMES         = 0x00000002;
        const MINIDUMP_MISC1_PROCESSOR_POWER_INFO  = 0x00000004;
        const MINIDUMP_MISC3_PROCESS_INTEGRITY     = 0x00000010;
        const MINIDUMP_MISC3_PROCESS_EXECUTE_FLAGS = 0x00000020;
        const MINIDUMP_MISC3_TIMEZONE              = 0x00000040;
        const MINIDUMP_MISC3_PROTECTED_PROCESS     = 0x00000080;
        const MINIDUMP_MISC4_BUILDSTRING           = 0x00000100;
        const MINIDUMP_MISC5_PROCESS_COOKIE        = 0x00000200;
    }
}

/// A list of memory regions in a minidump
///
/// This is the format of the [`MINIDUMP_STREAM_TYPE::MemoryInfoListStream`]. The individual
/// [`MINIDUMP_MEMORY_INFO`] entries follow this header in the stream.
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_memory_info_list
#[derive(Debug, Clone, Pread, SizeWith)]
pub struct MINIDUMP_MEMORY_INFO_LIST {
    /// The size of this header
    pub size_of_header: u32,
    /// The size of each entry in the list
    pub size_of_entry: u32,
    /// The number of entries in the list
    pub number_of_entries: u64,
}

/// Information about a memory region in a minidump
///
/// This struct matches the [Microsoft struct][msdn] of the same name.
///
/// [msdn]: https://docs.microsoft.com/en-us/windows/win32/api/minidumpapiset/ns-minidumpapiset-minidump_memory_info
#[derive(Debug, Clone, PartialEq, Eq, Pread, SizeWith)]
pub struct MINIDUMP_MEMORY_INFO {
    /// The base address of the region of pages
    pub base_address: u64,
    /// The base address of a range of pages in this region
    pub allocation_base: u64,
    /// The memory protection when the region was initially allocated
    ///
    /// See [`MemoryProtection`] for valid values.
    pub allocation_protection: u32,
    pub __alignment1: u32,
    /// The size of the region in which all pages have identical attributes, in bytes
    pub region_size: u64,
    /// The state of the pages in the region
    ///
    /// See [`MemoryState`] for valid values.
    pub state: u32,
    /// The access protection of the pages in the region
    ///
    /// See [`MemoryProtection`] for valid values.
    pub protection: u32,
    /// The type of pages in the region
    ///
    /// See [`MemoryType`] for valid values.
    pub _type: u32,
    pub __alignment2: u32,
}

bitflags! {
    /// Potential values for [`MINIDUMP_MEMORY_INFO::state`]
    pub struct MemoryState: u32 {
        const MEM_COMMIT  = 0x01000;
        const MEM_FREE    = 0x10000;
        const MEM_RESERVE = 0x02000;
    }
}

bitflags! {
    /// Potential values for [`MINIDUMP_MEMORY_INFO::protection`] and `allocation_protection`
    ///
    /// See [Microsoft's documentation][msdn] for details.
    ///
    /// [msdn]: https://docs.microsoft.com/en-us/windows/win32/Memory/memory-protection-constants
    pub struct MemoryProtection: u32 {
        const PAGE_NOACCESS           = 0x01;
        const PAGE_READONLY           = 0x02;
        const PAGE_READWRITE          = 0x04;
        const PAGE_WRITECOPY          = 0x08;
        const PAGE_EXECUTE            = 0x10;
        const PAGE_EXECUTE_READ       = 0x20;
        const PAGE_EXECUTE_READWRITE  = 0x40;
        const PAGE_EXECUTE_WRITECOPY  = 0x80;
        const ACCESS_MASK             = 0xff;
        const PAGE_GUARD              = 0x100;
        const PAGE_NOCACHE            = 0x200;
        const PAGE_WRITECOMBINE       = 0x400;
    }
}

bitflags! {
    /// Potential values for [`MINIDUMP_MEMORY_INFO::_type`]
    pub struct MemoryType: u32 {
        const MEM_PRIVATE = 0x00020000;
        const MEM_MAPPED  = 0x00040000;
        const MEM_IMAGE   = 0x01000000;
    }
}

/// A Breakpad extension containing some additional process information
///
/// Taken from the definition in Breakpad's [minidump_format.h][fmt].
///
/// [fmt]: https://chromium.googlesource.com/breakpad/breakpad/+/88d8114fda3e4a7292654bd6ac0c34d6c88a8121/src/google_breakpad/common/minidump_format.h#962
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct MINIDUMP_BREAKPAD_INFO {
    pub validity: u32,
    /// The Thread ID of the handler thread
    pub dump_thread_id: u32,
    /// The Thread ID of the thread that requested the dump
    pub requesting_thread_id: u32,
}

bitflags! {
    /// Potential values for [`MINIDUMP_BREAKPAD_INFO::validity`]
    ///
    /// Taken from definitions in Breakpad's [minidump_format.h][fmt].
    ///
    /// [fmt]: https://chromium.googlesource.com/breakpad/breakpad/+/88d8114fda3e4a7292654bd6ac0c34d6c88a8121/src/google_breakpad/common/minidump_format.h#989
    pub struct BreakpadInfoValid: u32 {
        const DumpThreadId       = 1 << 0;
        const RequestingThreadId = 1 << 1;
    }
}

/// A Breakpad extension containing information about an assertion that terminated the process
///
/// Taken from the definition in Breakpad's [minidump_format.h][fmt].
///
/// [fmt]: https://chromium.googlesource.com/breakpad/breakpad/+/88d8114fda3e4a7292654bd6ac0c34d6c88a8121/src/google_breakpad/common/minidump_format.h#998
#[derive(Debug, Clone, Pread, SizeWith)]
pub struct MINIDUMP_ASSERTION_INFO {
    /// The assertion that failed, as a 0-terminated UTF16-LE string
    pub expression: [u16; 128],
    /// The function containing the assertion, as a 0-terminated UTF16-LE string
    pub function: [u16; 128],
    /// The source file containing the assertion, as a 0-terminated UTF16-LE string
    pub file: [u16; 128],
    /// The line number in [`file`] containing the assertion
    pub line: u32,
    /// The assertion type
    pub _type: u32,
}

/// Known values of [`MINIDUMP_ASSERTION_INFO::_type`]
/// Taken from the definition in Breakpad's [minidump_format.h][fmt].
///
/// [fmt]: https://chromium.googlesource.com/breakpad/breakpad/+/88d8114fda3e4a7292654bd6ac0c34d6c88a8121/src/google_breakpad/common/minidump_format.h#1011
#[repr(u32)]
#[derive(Copy, Clone, PartialEq, Eq, Debug, Primitive)]
pub enum AssertionType {
    Unknown = 0,
    InvalidParameter = 1,
    PureVirtualCall = 2,
}

/// Dynamic linker information for a shared library on 32-bit Linux
///
/// This is functionally equivalent to the data in `struct link_map` defined in <link.h>.
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct LINK_MAP_32 {
    pub addr: u32,
    /// The offset of a string containing the filename of this shared library
    pub name: RVA,
    pub ld: u32,
}

/// DSO debug data for 32-bit Linux minidumps
///
/// Used when converting minidumps to coredumps. This is functionally equivalent to the data
/// in `struct r_debug` defined in <link.h>.
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct DSO_DEBUG_32 {
    /// The version number of this protocol, from `r_debug.r_version`
    pub version: u32,
    /// The offset of an array of [`LINK_MAP_32`] structs
    pub map: RVA,
    /// The number of [`LINK_MAP_32`] entries pointed to by `map`
    pub dso_count: u32,
    /// The address of a function internal to the run-time linker used by debuggers to
    /// set a breakpoint.
    pub brk: u32,
    /// Base address the linker is loaded at
    pub ldbase: u32,
    /// The address of the "dynamic structure"
    pub dynamic: u32,
}

/// Dynamic linker information for a shared library on 64-bit Linux
///
/// This is functionally equivalent to the data in `struct link_map` defined in <link.h>.
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct LINK_MAP_64 {
    pub addr: u64,
    /// The offset of a string containing the filename of this shared library
    pub name: RVA,
    pub ld: u64,
}

/// DSO debug data for 64-bit Linux minidumps
///
/// Used when converting minidumps to coredumps. This is functionally equivalent to the data
/// in `struct r_debug` defined in <link.h>.
#[derive(Debug, Clone, Pread, Pwrite, SizeWith)]
pub struct DSO_DEBUG_64 {
    /// The version number of this protocol, from `r_debug.r_version`
    pub version: u32,
    /// The offset of an array of [`LINK_MAP_64`] structs
    pub map: RVA,
    /// The number of [`LINK_MAP_64`] entries pointed to by `map`
    pub dso_count: u32,
    /// The address of a function internal to the run-time linker used by debuggers to
    /// set a breakpoint.
    pub brk: u64,
    /// Base address the linker is loaded at
    pub ldbase: u64,
    /// The address of the "dynamic structure"
    pub dynamic: u64,
}

/// A variable-length UTF-8-encoded string carried within a minidump file.
///
/// See <https://crashpad.chromium.org/doxygen/structcrashpad_1_1MinidumpUTF8String.html>
#[derive(Debug, Clone)]
pub struct MINIDUMP_UTF8_STRING {
    /// The length of the #Buffer field in bytes, not including the `NUL` terminator.
    ///
    /// This field is interpreted as a byte count, not a count of Unicode code points.
    pub length: u32,
    /// The string, encoded in UTF-8, and terminated with a `NUL` byte.
    pub buffer: Vec<u8>,
}

impl<'a> scroll::ctx::TryFromCtx<'a, Endian> for MINIDUMP_UTF8_STRING {
    type Error = scroll::Error;

    fn try_from_ctx(src: &[u8], endian: Endian) -> Result<(Self, usize), Self::Error> {
        let offset = &mut 0;
        let length: u32 = src.gread_with(offset, endian)?;
        let data: &[u8] = src.gread_with(offset, length as usize + 1)?; // +1 for NUL

        if !data.ends_with(&[0]) {
            return Err(scroll::Error::Custom(
                "Minidump String does not end with NUL byte".to_owned(),
            ));
        }

        let buffer = data.to_vec();
        Ok((Self { length, buffer }, *offset))
    }
}

/// A key-value pair.
///
/// See <https://crashpad.chromium.org/doxygen/structcrashpad_1_1MinidumpSimpleStringDictionaryEntry.html>
#[derive(Clone, Debug, Pread, SizeWith)]
pub struct MINIDUMP_SIMPLE_STRING_DICTIONARY_ENTRY {
    /// RVA of a MinidumpUTF8String containing the key of a key-value pair.
    pub key: RVA,
    /// RVA of a MinidumpUTF8String containing the value of a key-value pair.
    pub value: RVA,
}

/// A list of key-value pairs.
///
/// See <https://crashpad.chromium.org/doxygen/structcrashpad_1_1MinidumpSimpleStringDictionary.html>
#[derive(Clone, Debug, Pread)]
pub struct MINIDUMP_SIMPLE_STRING_DICTIONARY {
    /// The number of key-value pairs present.
    pub count: u32,
}

/// A list of RVA pointers.
///
/// See <https://crashpad.chromium.org/doxygen/structcrashpad_1_1MinidumpRVAList.html>
#[derive(Clone, Debug, Pread)]
pub struct MINIDUMP_RVA_LIST {
    /// The number of pointers present.
    pub count: u32,
}

/// A typed annotation object.
///
/// See <https://crashpad.chromium.org/doxygen/structcrashpad_1_1MinidumpAnnotation.html>
#[derive(Clone, Debug, Pread)]
pub struct MINIDUMP_ANNOTATION {
    /// RVA of a MinidumpUTF8String containing the name of the annotation.
    pub name: RVA,
    /// The type of data stored in the `value` of the annotation. This may correspond to an \a
    /// `MINIDUMP_ANNOTATION_TYPE` or it may be user-defined.
    pub ty: u16,
    /// This field is always `0`.
    pub _reserved: u16,
    /// RVA of a `MinidumpByteArray` to the data for the annotation.
    pub value: RVA,
}

impl MINIDUMP_ANNOTATION {
    /// An invalid annotation. Reserved for internal use.
    ///
    /// See <https://crashpad.chromium.org/doxygen/classcrashpad_1_1Annotation.html#a734ee64cd20afdb78acb8656ed867d34>
    pub const TYPE_INVALID: u16 = 0;
    /// A `NUL`-terminated C-string.
    ///
    /// See <https://crashpad.chromium.org/doxygen/classcrashpad_1_1Annotation.html#a734ee64cd20afdb78acb8656ed867d34>
    pub const TYPE_STRING: u16 = 1;
    /// Clients may declare their own custom types by using values greater than this.
    ///
    /// See <https://crashpad.chromium.org/doxygen/classcrashpad_1_1Annotation.html#a734ee64cd20afdb78acb8656ed867d34>
    pub const TYPE_USER_DEFINED: u16 = 0x8000;
}

/// Additional Crashpad-specific information about a module carried within a minidump file.
///
/// This structure augments the information provided by MINIDUMP_MODULE. The minidump file must
/// contain a module list stream (::kMinidumpStreamTypeModuleList) in order for this structure to
/// appear.
///
/// This structure is versioned. When changing this structure, leave the existing structure intact
/// so that earlier parsers will be able to understand the fields they are aware of, and make
/// additions at the end of the structure. Revise #kVersion and document each field’s validity based
/// on #version, so that newer parsers will be able to determine whether the added fields are valid
/// or not.
///
/// See <https://crashpad.chromium.org/doxygen/structcrashpad_1_1MinidumpModuleCrashpadInfo.html>
#[derive(Clone, Debug, Pread)]
pub struct MINIDUMP_MODULE_CRASHPAD_INFO {
    /// The structure’s version number.
    ///
    /// Readers can use this field to determine which other fields in the structure are valid. Upon
    /// encountering a value greater than `VERSION`, a reader should assume that the structure’s
    /// layout is compatible with the structure defined as having value #kVersion.
    ///
    /// Writers may produce values less than `VERSION` in this field if there is no need for any
    /// fields present in later versions.
    pub version: u32,
    /// A `MinidumpRVAList` pointing to MinidumpUTF8String objects. The module controls the data
    /// that appears here.
    ///
    /// These strings correspond to `ModuleSnapshot::AnnotationsVector()` and do not duplicate
    /// anything in `simple_annotations` or `annotation_objects`.
    pub list_annotations: MINIDUMP_LOCATION_DESCRIPTOR,
    /// A `MinidumpSimpleStringDictionary` pointing to strings interpreted as key-value pairs. The
    /// module controls the data that appears here.
    ///
    /// These key-value pairs correspond to `ModuleSnapshot::AnnotationsSimpleMap()` and do not
    /// duplicate anything in `list_annotations` or `annotation_objects`.
    pub simple_annotations: MINIDUMP_LOCATION_DESCRIPTOR,
    /// A `MinidumpAnnotationList` object containing the annotation objects stored within the
    /// module. The module controls the data that appears here.
    ///
    /// These key-value pairs correspond to `ModuleSnapshot::AnnotationObjects()` and do not
    /// duplicate anything in `list_annotations` or `simple_annotations`.
    pub annotation_objects: MINIDUMP_LOCATION_DESCRIPTOR,
}

impl MINIDUMP_MODULE_CRASHPAD_INFO {
    /// The structure’s version number.
    ///
    /// Readers can use this field to determine which other fields in the structure are valid. Upon
    /// encountering a value greater than `VERSION`, a reader should assume that the structure’s
    /// layout is compatible with the structure defined as having value #kVersion.
    ///
    /// Writers may produce values less than `VERSION` in this field if there is no need for any
    /// fields present in later versions.
    pub const VERSION: u32 = 1;
}

/// A link between a `MINIDUMP_MODULE` structure and additional Crashpad-specific information about a
/// module carried within a minidump file.
///
/// See <https://crashpad.chromium.org/doxygen/structcrashpad_1_1MinidumpModuleCrashpadInfoLink.html>
#[derive(Clone, Debug, Pread, SizeWith)]
pub struct MINIDUMP_MODULE_CRASHPAD_INFO_LINK {
    /// A link to a MINIDUMP_MODULE structure in the module list stream.
    ///
    /// This field is an index into `MINIDUMP_MODULE_LIST::Modules`. This field’s value must be in
    /// the range of `MINIDUMP_MODULE_LIST::NumberOfEntries`.
    pub minidump_module_list_index: u32,

    /// A link to a MinidumpModuleCrashpadInfo structure.
    ///
    /// MinidumpModuleCrashpadInfo structures are accessed indirectly through
    /// `MINIDUMP_LOCATION_DESCRIPTOR` pointers to allow for future growth of the
    /// `MinidumpModuleCrashpadInfo` structure.
    pub location: MINIDUMP_LOCATION_DESCRIPTOR,
}

/// Additional Crashpad-specific information about modules carried within a minidump file.
///
/// This structure augments the information provided by `MINIDUMP_MODULE_LIST`. The minidump file
/// must contain a module list stream (::kMinidumpStreamTypeModuleList) in order for this structure
/// to appear.
///
/// `MinidumpModuleCrashpadInfoList::count` may be less than the value of
/// `MINIDUMP_MODULE_LIST::NumberOfModules` because not every `MINIDUMP_MODULE` structure carried
/// within the minidump file will necessarily have Crashpad-specific information provided by a
/// `MinidumpModuleCrashpadInfo` structure.
///
/// See <https://crashpad.chromium.org/doxygen/structcrashpad_1_1MinidumpModuleCrashpadInfoList.html>
#[derive(Clone, Debug, Pread)]
pub struct MINIDUMP_MODULE_CRASHPAD_INFO_LIST {
    /// The number of key-value pairs present.
    pub count: u32,
}

/// Additional Crashpad-specific information carried within a minidump file.
///
/// This structure is versioned. When changing this structure, leave the existing structure intact
/// so that earlier parsers will be able to understand the fields they are aware of, and make
/// additions at the end of the structure. Revise #kVersion and document each field’s validity based
/// on `version`, so that newer parsers will be able to determine whether the added fields are valid
/// or not.
///
/// See <https://crashpad.chromium.org/doxygen/structcrashpad_1_1MinidumpCrashpadInfo.html>
#[derive(Clone, Debug, Pread, SizeWith)]
pub struct MINIDUMP_CRASHPAD_INFO {
    /// The structure’s version number.
    ///
    /// Readers can use this field to determine which other fields in the structure are valid. Upon
    /// encountering a value greater than `VERSION`, a reader should assume that the structure’s
    /// layout is compatible with the structure defined as having value #kVersion.
    ///
    /// Writers may produce values less than `VERSION` in this field if there is no need for any
    /// fields present in later versions.
    pub version: u32,
    /// A `Uuid` identifying an individual crash report.
    ///
    /// This provides a stable identifier for a crash even as the report is converted to different
    /// formats, provided that all formats support storing a crash report ID.
    ///
    /// If no identifier is available, this field will contain zeroes.
    pub report_id: GUID,
    /// A `Uuid` identifying the client that crashed.
    ///
    /// Client identification is within the scope of the application, but it is expected that the
    /// identifier will be unique for an instance of Crashpad monitoring an application or set of
    /// applications for a user. The identifier shall remain stable over time.
    ///
    /// If no identifier is available, this field will contain zeroes.
    pub client_id: GUID,
    /// A MinidumpSimpleStringDictionary pointing to strings interpreted as key-value pairs.
    ///
    /// These key-value pairs correspond to Crashpad's `ProcessSnapshot::AnnotationsSimpleMap()`.
    pub simple_annotations: MINIDUMP_LOCATION_DESCRIPTOR,
    /// A pointer to a MinidumpModuleCrashpadInfoList structure.
    pub module_list: MINIDUMP_LOCATION_DESCRIPTOR,
}

impl MINIDUMP_CRASHPAD_INFO {
    /// The structure’s currently-defined version number.
    pub const VERSION: u32 = 1;
}

/// MacOS __DATA,__crash_info data.
///
/// This is the format of the [`MINIDUMP_STREAM_TYPE::MozMacosCrashInfoStream`]. The individual
/// [`MINIDUMP_MAC_CRASH_INFO_RECORD`] entries follow this header in the stream.
#[derive(Debug, Pread, SizeWith)]
pub struct MINIDUMP_MAC_CRASH_INFO {
    pub stream_type: u32,
    /// The number of [`MINIDUMP_MAC_CRASH_INFO_RECORD`]s.
    pub record_count: u32,
    /// The size of the "fixed-size" part of MINIDUMP_MAC_CRASH_INFO_RECORD.
    /// Used to offset to the variable-length portion of the struct, where
    /// C-strings are stored. This allows us to access all the fields we know
    /// about, even when newer versions of this format introduce new ones.
    pub record_start_size: u32,
    pub records: [MINIDUMP_LOCATION_DESCRIPTOR; 20],
}

// MozMacosCrashInfoStream is a versioned format where new fields are added to
// the end of the struct, but there are also variable-length c-string fields
// that follow the "fixed-size" fields. As such, the versioned strings are separated
// out into their own separate struct with the same version. So e.g.
//
// MINIDUMP_MAC_CRASH_INFO_RECORD_4 should be paired with MINIDUMP_MAC_CRASH_INFO_RECORD_STRINGS_4

multi_structs! {
    /// Contents of MacOS's `<CrashReporterClient.h>`'s `crashreporter_annotations_t`,
    /// but with the by-reference C-strings hoisted out to the end of the struct
    /// and inlined (so this is a variable-length struct).
    ///
    /// The variable-length strings are listed in [`MINIDUMP_MAC_CRASH_INFO_RECORD_STRINGS`].
    /// Use [`MINIDUMP_MAC_CRASH_INFO::record_start_size`] to access them.
    pub struct MINIDUMP_MAC_CRASH_INFO_RECORD {
      pub stream_type: u64,
      // Version of this format, currently at 5.
      //
      // Although theoretically this field being here means we can support multiple
      // versions of this struct in one [`MINIDUMP_MAC_CRASH_INFO`] stream, our reliance on
      // [`MINIDUMP_MAC_CRASH_INFO::record_start_size`] means we can't actually handle
      // such a heterogeneous situation. So all records should have the same version value.
      pub version: u64,
    }
    // Includes fields from MINIDUMP_MAC_CRASH_INFO_RECORD
    /// Contents of MacOS's `<CrashReporterClient.h>`'s `crashreporter_annotations_t`,
    /// but with the by-reference C-strings hoisted out to the end of the struct
    /// and inlined (so this is a variable-length struct).
    ///
    /// The variable-length strings are listed in [`MINIDUMP_MAC_CRASH_INFO_RECORD_STRINGS_4`].
    /// Use [`MINIDUMP_MAC_CRASH_INFO::record_start_size`] to access them.
    pub struct MINIDUMP_MAC_CRASH_INFO_RECORD_4 {
        pub thread: u64,
        pub dialog_mode: u64,
    }
    // Includes fields from MINIDUMP_MAC_CRASH_INFO_RECORD and MINIDUMP_MAC_CRASH_INFO_RECORD_4
    /// Contents of MacOS's `<CrashReporterClient.h>`'s `crashreporter_annotations_t`,
    /// but with the by-reference C-strings hoisted out to the end of the struct
    /// and inlined (so this is a variable-length struct).
    ///
    /// The variable-length strings are listed in [`MINIDUMP_MAC_CRASH_INFO_RECORD_STRINGS_5`].
    /// Use [`MINIDUMP_MAC_CRASH_INFO::record_start_size`] to access them.
    pub struct MINIDUMP_MAC_CRASH_INFO_RECORD_5 {
        pub abort_cause: u64,
    }
}

macro_rules! replace_expr {
    ($_t:tt $sub:expr) => {
        $sub
    };
}

macro_rules! count_tts {
    ($($tts:tt)*) => {0usize $(+ replace_expr!($tts 1usize))*};
}

// Like multi_structs but specialized for a struct of strings that can be set by index.
macro_rules! multi_strings {
    // With no trailing struct left, terminate.
    (@next { $($prev:tt)* }) => {};
    // Declare the next struct, including fields from previous structs.
    (@next { $($prev:tt)* } $(#[$attr:meta])* pub struct $name:ident { $($cur:tt)* } $($tail:tt)* ) => {
        // Prepend fields from previous structs to this struct.
        multi_strings!($(#[$attr])* pub struct $name { $($prev)* $($cur)* } $($tail)*);
    };
    // Declare a single struct.
    ($(#[$attr:meta])* pub struct $name:ident { $( pub $field:ident: $t:tt, )* } $($tail:tt)* ) => {
        $(#[$attr])*
        #[derive(Default, Debug, Clone)]
        pub struct $name {
            $( pub $field: $t, )*
        }

        impl $name {
            pub fn num_strings() -> usize {
                count_tts!($($t)*)
            }

            #[allow(unused_variables, unused_mut)]
            pub fn set_string(&mut self, idx: usize, string: String) {
                let mut cur_idx = 0;
                $(if cur_idx == idx {
                    self.$field = string;
                    return;
                }
                cur_idx += 1;
                )*
                panic!("string index out of bounds {} >= {}", idx, cur_idx);
            }
        }

        // Persist its fields down to the following structs.
        multi_strings!(@next { $( pub $field: $t, )* } $($tail)*);
    };
}

multi_strings! {
    /// Variable-length data for [`MINIDUMP_MAC_CRASH_INFO_RECORD`].
    pub struct MINIDUMP_MAC_CRASH_INFO_RECORD_STRINGS {
        // No strings in the base version
    }

    // Includes fields from [`MINIDUMP_MAC_CRASH_INFO_RECORD_STRINGS`]
    /// Variable-length data for [`MINIDUMP_MAC_CRASH_INFO_RECORD_4`].
    pub struct MINIDUMP_MAC_CRASH_INFO_RECORD_STRINGS_4 {
        pub module_path: String,
        pub message: String,
        pub signature_string: String,
        pub backtrace: String,
        pub message2: String,
    }

    // Includes fields from [`MINIDUMP_MAC_CRASH_INFO_RECORD_STRINGS_4`]
    /// Variable-length data for [`MINIDUMP_MAC_CRASH_INFO_RECORD_5`].
    pub struct MINIDUMP_MAC_CRASH_INFO_RECORD_STRINGS_5 {
        // No new strings
    }
}

/// The maximum supported size of a C-string in [`MINIDUMP_MAC_CRASH_INFO_RECORD`].
///
/// Assume the stream is corrupted if a string is longer than this.
pub const MAC_CRASH_INFO_STRING_MAX_SIZE: usize = 8192;

/// The maximum supported count of [`MINIDUMP_MAC_CRASH_INFO_RECORD`]s.
///
/// In principle there should only be one or two non-empty __DATA,__crash_info
/// sections per process. But the __crash_info section is almost entirely
/// undocumented, so just in case we set a large maximum.
pub const MAC_CRASH_INFOS_MAX: usize = 20;

bitflags! {
    /// Possible values of [`ARMCpuInfo::elf_hwcaps`]
    ///
    /// This matches the Linux kernel definitions from [<asm/hwcaps.h>][hwcap].
    ///
    /// [hwcap]: https://elixir.bootlin.com/linux/latest/source/arch/arm/include/uapi/asm/hwcap.h
    pub struct ArmElfHwCaps: u32 {
        const HWCAP_SWP       = (1 << 0);
        const HWCAP_HALF      = (1 << 1);
        const HWCAP_THUMB     = (1 << 2);
        const HWCAP_26BIT     = (1 << 3);
        const HWCAP_FAST_MULT = (1 << 4);
        const HWCAP_FPA       = (1 << 5);
        const HWCAP_VFP       = (1 << 6);
        const HWCAP_EDSP      = (1 << 7);
        const HWCAP_JAVA      = (1 << 8);
        const HWCAP_IWMMXT    = (1 << 9);
        const HWCAP_CRUNCH    = (1 << 10);
        const HWCAP_THUMBEE   = (1 << 11);
        const HWCAP_NEON      = (1 << 12);
        const HWCAP_VFPv3     = (1 << 13);
        const HWCAP_VFPv3D16  = (1 << 14);
        const HWCAP_TLS       = (1 << 15);
        const HWCAP_VFPv4     = (1 << 16);
        const HWCAP_IDIVA     = (1 << 17);
        const HWCAP_IDIVT     = (1 << 18);
        const HWCAP_VFPD32    = (1 << 19);
        const HWCAP_IDIV      = ArmElfHwCaps::HWCAP_IDIVA.bits | Self::HWCAP_IDIVT.bits;
        const HWCAP_LPAE      = (1 << 20);
        const HWCAP_EVTSTRM   = (1 << 21);
    }
}