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//! This crate provides types for identifiers of object files, such as executables, dynamic
//! libraries or debug companion files. The concept originates in Google Breakpad and defines two
//! types:
//!
//! - [`CodeId`]: Identifies the file containing source code, i.e. the actual library or
//! executable. The identifier is platform dependent and implementation defined. Thus, there is
//! no canonical representation.
//! - [`DebugId`]: Identifies a debug information file, which may or may not use information from
//! the Code ID. The contents are also implementation defined, but as opposed to `CodeId`, the
//! structure is streamlined across platforms. It is also guaranteed to be 32 bytes in size.
//!
//! [`CodeId`]: struct.CodeId.html
//! [`DebugId`]: struct.DebugId.html
#![warn(missing_docs)]
use std::error;
use std::fmt;
use std::fmt::Write;
use std::str;
use uuid::{Bytes, Uuid};
/// Indicates an error parsing a [`DebugId`](struct.DebugId.html).
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub struct ParseDebugIdError;
impl error::Error for ParseDebugIdError {}
impl fmt::Display for ParseDebugIdError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "invalid debug identifier")
}
}
#[derive(Clone, Copy, Debug)]
struct ParseOptions {
allow_hyphens: bool,
require_appendix: bool,
allow_tail: bool,
}
/// Unique identifier for debug information files and their debug information.
///
/// This type is analogous to [`CodeId`], except that it identifies a debug file instead of the
/// actual library or executable. One some platforms, a `DebugId` is an alias for a `CodeId` but the
/// exact rules around this are complex. On Windows, the identifiers are completely different and
/// refer to separate files.
///
/// The string representation must be between 33 and 40 characters long and consist of:
///
/// 1. 36 character hyphenated hex representation of the UUID field
/// 2. 1-16 character lowercase hex representation of the u32 appendix
///
/// The debug identifier is compatible to Google Breakpad. Use [`DebugId::breakpad`] to get a
/// breakpad string representation of this debug identifier.
///
/// There is one exception to this: for the old PDB 2.0 format the debug identifier consists
/// of only a 32-bit integer + age resulting in a string representation of between 9 and 16
/// hex characters.
///
/// # Example
///
/// ```
/// # extern crate debugid;
/// use std::str::FromStr;
/// use debugid::DebugId;
///
/// # fn foo() -> Result<(), ::debugid::ParseDebugIdError> {
/// let id = DebugId::from_str("dfb8e43a-f242-3d73-a453-aeb6a777ef75-a")?;
/// assert_eq!("dfb8e43a-f242-3d73-a453-aeb6a777ef75-a".to_string(), id.to_string());
/// # Ok(())
/// # }
///
/// # fn main() { foo().unwrap() }
/// ```
///
/// # In-memory representation
///
/// The in-memory representation takes up 32 bytes and can be directly written to storage
/// and mapped back into an object reference.
///
/// ```
/// use std::str::FromStr;
/// use debugid::DebugId;
///
/// let debug_id = DebugId::from_str("dfb8e43a-f242-3d73-a453-aeb6a777ef75-a").unwrap();
///
/// let slice = &[debug_id];
/// let ptr = slice.as_ptr() as *const u8;
/// let len = std::mem::size_of_val(slice);
/// let buf: &[u8] = unsafe { std::slice::from_raw_parts(ptr, len) };
///
/// let mut new_buf: Vec<u8> = Vec::new();
/// std::io::copy(&mut std::io::Cursor::new(buf), &mut new_buf).unwrap();
///
/// let ptr = new_buf.as_ptr() as *const DebugId;
/// let new_debug_id = unsafe { &*ptr };
///
/// assert_eq!(*new_debug_id, debug_id);
/// ```
///
/// As long the bytes were written using the same major version of this crate you will be
/// able to read it again like this.
///
/// [`CodeId`]: struct.CodeId.html
/// [`DebugId::breakpad`]: struct.DebugId.html#method.breakpad
// This needs to be backwards compatible also in its exact in-memory byte-layout since this
// struct is directly mapped from disk in e.g. Symbolic SymCache formats. The first version
// of this struct was defined as:
//
// ```rust
// struct DebugId {
// uuid: Uuid,
// appendix: u32,
// _padding: [u8; 12],
// }
// ```
//
// For this reason the current `typ` byte represents the type of `DebugId` stored in the
// `Bytes`:
//
// - `0u8`: The `bytes` field contains a UUID.
// - `1u8`: The first 4 bytes of the `bytes` field contain a big-endian u32, the remaining
// bytes are 0.
#[repr(C, packed)]
#[derive(Default, Eq, PartialEq, Ord, PartialOrd, Hash, Clone, Copy)]
pub struct DebugId {
bytes: Bytes,
appendix: u32,
_padding: [u8; 11],
typ: u8,
}
impl DebugId {
/// Constructs an empty debug identifier, containing only zeros.
pub fn nil() -> Self {
Self::default()
}
/// Constructs a `DebugId` from its `uuid`.
pub fn from_uuid(uuid: Uuid) -> Self {
Self::from_parts(uuid, 0)
}
/// Constructs a `DebugId` from its `uuid` and `appendix` parts.
pub fn from_parts(uuid: Uuid, appendix: u32) -> Self {
DebugId {
bytes: *uuid.as_bytes(),
appendix,
typ: 0,
_padding: [0; 11],
}
}
/// Constructs a `DebugId` from a Microsoft little-endian GUID and age.
pub fn from_guid_age(guid: &[u8], age: u32) -> Result<Self, ParseDebugIdError> {
if guid.len() != 16 {
return Err(ParseDebugIdError);
}
let uuid = Uuid::from_bytes([
guid[3], guid[2], guid[1], guid[0], guid[5], guid[4], guid[7], guid[6], guid[8],
guid[9], guid[10], guid[11], guid[12], guid[13], guid[14], guid[15],
]);
Ok(DebugId::from_parts(uuid, age))
}
/// Constructs a `DebugId` from a PDB 2.0 timestamp and age.
pub fn from_pdb20(timestamp: u32, age: u32) -> Self {
// The big-endian byte-order here has to match the one used to read this number in
// the DebugId::timestamp method.
DebugId {
bytes: [
(timestamp >> 24) as u8,
(timestamp >> 16) as u8,
(timestamp >> 8) as u8,
timestamp as u8,
0u8,
0u8,
0u8,
0u8,
0u8,
0u8,
0u8,
0u8,
0u8,
0u8,
0u8,
0u8,
],
appendix: age,
_padding: [0u8; 11],
typ: 1u8,
}
}
/// Parses a breakpad identifier from a string.
pub fn from_breakpad(string: &str) -> Result<Self, ParseDebugIdError> {
let options = ParseOptions {
allow_hyphens: false,
require_appendix: true,
allow_tail: false,
};
Self::parse_str(string, options).ok_or(ParseDebugIdError)
}
/// Returns the UUID part of the code module's debug_identifier.
///
/// If this is a debug identifier for the PDB 2.0 format an invalid UUID is returned
/// where only the first 4 bytes are filled in and the remainder of the bytes are 0.
/// This means the UUID has variant [`uuid::Variant::NCS`] and an unknown version,
/// [`Uuid::get_version`] will return `None`, which is not a valid UUID.
///
/// This may seem odd however does seem reasonable:
///
/// - Every [`DebugId`] can be represented as [`Uuid`] and will still mostly look
/// reasonable e.g. in comparisons etc.
/// - The PDB 2.0 format is very old and very unlikely to appear practically.
pub fn uuid(&self) -> Uuid {
Uuid::from_bytes(self.bytes)
}
/// Returns the appendix part of the code module's debug identifier.
///
/// On Windows, this is an incrementing counter to identify the build.
/// On all other platforms, this value will always be zero.
pub fn appendix(&self) -> u32 {
self.appendix
}
/// Returns whether this identifier is nil, i.e. it consists only of zeros.
pub fn is_nil(&self) -> bool {
self.bytes == [0u8; 16] && self.appendix == 0
}
/// Returns whether this identifier is from the PDB 2.0 format.
pub fn is_pdb20(&self) -> bool {
self.typ == 1
}
/// Returns a wrapper which when formatted via `fmt::Display` will format a
/// a breakpad identifier.
pub fn breakpad(&self) -> BreakpadFormat<'_> {
BreakpadFormat { inner: self }
}
fn parse_str(string: &str, options: ParseOptions) -> Option<Self> {
let is_hyphenated = string.get(8..9) == Some("-");
if is_hyphenated && !options.allow_hyphens || !string.is_ascii() {
return None;
}
// Can the PDB 2.0 format match? This can never be true for a valid UUID.
let min_len = if is_hyphenated { 10 } else { 9 };
let max_len = if is_hyphenated { 17 } else { 16 };
if min_len <= string.len() && string.len() <= max_len {
let timestamp_str = string.get(..8)?;
let timestamp = u32::from_str_radix(timestamp_str, 16).ok()?;
let appendix_str = match is_hyphenated {
true => string.get(9..)?,
false => string.get(8..)?,
};
let appendix = u32::from_str_radix(appendix_str, 16).ok()?;
return Some(Self::from_pdb20(timestamp, appendix));
}
let uuid_len = if is_hyphenated { 36 } else { 32 };
let uuid = string.get(..uuid_len)?.parse().ok()?;
if !options.require_appendix && string.len() == uuid_len {
return Some(Self::from_parts(uuid, 0));
}
let mut appendix_str = &string[uuid_len..];
if is_hyphenated ^ appendix_str.starts_with('-') {
return None; // Require a hyphen if and only if we're hyphenated.
} else if is_hyphenated {
appendix_str = &appendix_str[1..]; // Skip the hyphen for parsing.
}
if options.allow_tail && appendix_str.len() > 8 {
appendix_str = &appendix_str[..8];
}
// Parse the appendix, which fails on empty strings.
let appendix = u32::from_str_radix(appendix_str, 16).ok()?;
Some(Self::from_parts(uuid, appendix))
}
/// Returns the PDB 2.0 timestamp.
///
/// Only valid if you know this is a PDB 2.0 debug identifier.
fn timestamp(&self) -> u32 {
u32::from_be_bytes([self.bytes[0], self.bytes[1], self.bytes[2], self.bytes[3]])
}
}
impl fmt::Debug for DebugId {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
let uuid = self.uuid();
f.debug_struct("DebugId")
.field("uuid", &uuid.hyphenated().to_string())
.field("appendix", &self.appendix())
.finish()
}
}
impl fmt::Display for DebugId {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self.is_pdb20() {
true => {
let timestamp = self.timestamp();
write!(f, "{:08X}", timestamp)?;
}
false => {
let uuid = self.uuid();
uuid.fmt(f)?;
}
}
if self.appendix > 0 {
write!(f, "-{:x}", { self.appendix })?;
}
Ok(())
}
}
impl str::FromStr for DebugId {
type Err = ParseDebugIdError;
fn from_str(string: &str) -> Result<Self, ParseDebugIdError> {
let options = ParseOptions {
allow_hyphens: true,
require_appendix: false,
allow_tail: true,
};
Self::parse_str(string, options).ok_or(ParseDebugIdError)
}
}
impl From<Uuid> for DebugId {
fn from(uuid: Uuid) -> Self {
DebugId::from_uuid(uuid)
}
}
impl From<(Uuid, u32)> for DebugId {
fn from(tuple: (Uuid, u32)) -> Self {
let (uuid, appendix) = tuple;
DebugId::from_parts(uuid, appendix)
}
}
/// Wrapper around [`DebugId`] for Breakpad formatting.
///
/// **Example:**
///
/// ```
/// # extern crate debugid;
/// use std::str::FromStr;
/// use debugid::DebugId;
///
/// # fn foo() -> Result<(), debugid::ParseDebugIdError> {
/// let id = DebugId::from_breakpad("DFB8E43AF2423D73A453AEB6A777EF75a")?;
/// assert_eq!("DFB8E43AF2423D73A453AEB6A777EF75a".to_string(), id.breakpad().to_string());
/// # Ok(())
/// # }
///
/// # fn main() { foo().unwrap() }
/// ```
///
/// [`DebugId`]: struct.DebugId.html
#[derive(Debug)]
pub struct BreakpadFormat<'a> {
inner: &'a DebugId,
}
impl<'a> fmt::Display for BreakpadFormat<'a> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self.inner.is_pdb20() {
true => {
let timestamp = self.inner.timestamp();
write!(f, "{:08X}{:x}", timestamp, self.inner.appendix())
}
false => {
let uuid = self.inner.uuid();
write!(f, "{:X}{:x}", uuid.simple(), self.inner.appendix())
}
}
}
}
/// Indicates an error parsing a [`CodeId`](struct.CodeId.html).
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub struct ParseCodeIdError;
impl error::Error for ParseCodeIdError {}
impl fmt::Display for ParseCodeIdError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "invalid code identifier")
}
}
/// Unique platform-dependent identifier of code files.
///
/// This identifier assumes a string representation that depends on the platform and compiler used.
/// The representation only retains hex characters and canonically stores lower case.
///
/// There are the following known formats:
///
/// - **MachO UUID**: The unique identifier of a Mach binary, specified in the `LC_UUID` load
/// command header.
/// - **GNU Build ID**: Contents of the `.gnu.build-id` note or section contents formatted as
/// lowercase hex string.
/// - **PE Timestamp**: Timestamp and size of image values from a Windows PE header. The size of
/// image value is truncated, so the length of the `CodeId` might not be a multiple of 2.
#[derive(Clone, Default, Eq, Hash, Ord, PartialEq, PartialOrd)]
pub struct CodeId {
inner: String,
}
impl CodeId {
/// Constructs an empty code identifier.
pub fn nil() -> Self {
Self::default()
}
/// Constructs a `CodeId` from its string representation.
pub fn new(mut string: String) -> Self {
string.retain(|c| c.is_ascii_hexdigit());
string.make_ascii_lowercase();
CodeId { inner: string }
}
/// Constructs a `CodeId` from a binary slice.
pub fn from_binary(slice: &[u8]) -> Self {
let mut string = String::with_capacity(slice.len() * 2);
for byte in slice {
write!(&mut string, "{:02x}", byte).expect("");
}
Self::new(string)
}
/// Returns whether this identifier is nil, i.e. it is empty.
pub fn is_nil(&self) -> bool {
self.inner.is_empty()
}
/// Returns the string representation of this code identifier.
pub fn as_str(&self) -> &str {
self.inner.as_str()
}
}
impl fmt::Display for CodeId {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.write_str(&self.inner)
}
}
impl fmt::Debug for CodeId {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "CodeId({})", self)
}
}
impl From<String> for CodeId {
fn from(string: String) -> Self {
Self::new(string)
}
}
impl From<&'_ str> for CodeId {
fn from(string: &str) -> Self {
Self::new(string.into())
}
}
impl AsRef<str> for CodeId {
fn as_ref(&self) -> &str {
self.as_str()
}
}
impl str::FromStr for CodeId {
type Err = ParseCodeIdError;
fn from_str(string: &str) -> Result<Self, ParseCodeIdError> {
Ok(Self::new(string.into()))
}
}
#[cfg(feature = "serde")]
mod serde_support {
use serde::de::{self, Deserialize, Deserializer, Unexpected, Visitor};
use serde::ser::{Serialize, Serializer};
use super::*;
impl Serialize for CodeId {
fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
serializer.serialize_str(self.as_str())
}
}
impl<'de> Deserialize<'de> for CodeId {
fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
let string = String::deserialize(deserializer)?;
Ok(CodeId::new(string))
}
}
impl<'de> Deserialize<'de> for DebugId {
fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
struct V;
impl<'de> Visitor<'de> for V {
type Value = DebugId;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("DebugId")
}
fn visit_str<E: de::Error>(self, value: &str) -> Result<DebugId, E> {
value
.parse()
.map_err(|_| de::Error::invalid_value(Unexpected::Str(value), &self))
}
}
deserializer.deserialize_str(V)
}
}
impl Serialize for DebugId {
fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
serializer.serialize_str(&self.to_string())
}
}
}