1 //! This module contains standard C-mapped types for types not in the original crate.
3 /// Auto-generated C-mapped types for templated containers
6 use bitcoin::Transaction as BitcoinTransaction;
7 use bitcoin::hashes::Hash;
8 use bitcoin::secp256k1::PublicKey as SecpPublicKey;
9 use bitcoin::secp256k1::SecretKey as SecpSecretKey;
10 use bitcoin::secp256k1::ecdsa::Signature as SecpSignature;
11 use bitcoin::secp256k1::Error as SecpError;
12 use bitcoin::secp256k1::ecdsa::RecoveryId;
13 use bitcoin::secp256k1::ecdsa::RecoverableSignature as SecpRecoverableSignature;
14 use bitcoin::secp256k1::Scalar as SecpScalar;
16 use bitcoin::util::address;
18 use core::convert::TryInto; // Bindings need at least rustc 1.34
19 use core::ffi::c_void;
21 #[cfg(feature = "std")]
22 pub(crate) use std::io::{self, Cursor, Read};
23 #[cfg(feature = "no-std")]
24 pub(crate) use core2::io::{self, Cursor, Read};
25 #[cfg(feature = "no-std")]
26 use alloc::{boxed::Box, vec::Vec, string::String};
28 use core::convert::TryFrom;
31 /// A dummy struct of which an instance must never exist.
32 /// This corresponds to the Rust type `Infallible`, or, in unstable rust, `!`
33 pub struct NotConstructable {
34 _priv_thing: core::convert::Infallible,
36 impl From<core::convert::Infallible> for NotConstructable {
37 fn from(_: core::convert::Infallible) -> Self { unreachable!(); }
40 /// Integer in the range `0..32`
41 #[derive(PartialEq, Eq, Copy, Clone)]
42 #[allow(non_camel_case_types)]
46 impl From<bech32::u5> for u5 {
47 fn from(o: bech32::u5) -> Self { Self(o.to_u8()) }
49 impl Into<bech32::u5> for u5 {
50 fn into(self) -> bech32::u5 { bech32::u5::try_from_u8(self.0).expect("u5 objects must be in the range 0..32") }
53 /// Integer in the range `0..=16`
54 #[derive(PartialEq, Eq, Copy, Clone)]
56 pub struct WitnessVersion(u8);
58 impl From<address::WitnessVersion> for WitnessVersion {
59 fn from(o: address::WitnessVersion) -> Self { Self(o.to_num()) }
61 impl Into<address::WitnessVersion> for WitnessVersion {
62 fn into(self) -> address::WitnessVersion {
63 address::WitnessVersion::try_from(self.0).expect("WitnessVersion objects must be in the range 0..=16")
69 /// Represents a valid secp256k1 public key serialized in "compressed form" as a 33 byte array.
70 pub struct PublicKey {
71 /// The bytes of the public key
72 pub compressed_form: [u8; 33],
75 pub(crate) fn from_rust(pk: &SecpPublicKey) -> Self {
77 compressed_form: pk.serialize(),
80 pub(crate) fn into_rust(&self) -> SecpPublicKey {
81 SecpPublicKey::from_slice(&self.compressed_form).unwrap()
83 pub(crate) fn is_null(&self) -> bool { self.compressed_form[..] == [0; 33][..] }
84 pub(crate) fn null() -> Self { Self { compressed_form: [0; 33] } }
89 /// Represents a valid secp256k1 secret key serialized as a 32 byte array.
90 pub struct SecretKey {
91 /// The bytes of the secret key
95 // from_rust isn't implemented for a ref since we just return byte array refs directly
96 pub(crate) fn from_rust(sk: SecpSecretKey) -> Self {
97 let mut bytes = [0; 32];
98 bytes.copy_from_slice(&sk[..]);
101 pub(crate) fn into_rust(&self) -> SecpSecretKey {
102 SecpSecretKey::from_slice(&self.bytes).unwrap()
108 /// Represents a secp256k1 signature serialized as two 32-byte numbers
109 pub struct Signature {
110 /// The bytes of the signature in "compact" form
111 pub compact_form: [u8; 64],
114 pub(crate) fn from_rust(pk: &SecpSignature) -> Self {
116 compact_form: pk.serialize_compact(),
119 pub(crate) fn into_rust(&self) -> SecpSignature {
120 SecpSignature::from_compact(&self.compact_form).unwrap()
122 // The following are used for Option<Signature> which we support, but don't use anymore
123 #[allow(unused)] pub(crate) fn is_null(&self) -> bool { self.compact_form[..] == [0; 64][..] }
124 #[allow(unused)] pub(crate) fn null() -> Self { Self { compact_form: [0; 64] } }
129 /// Represents a secp256k1 signature serialized as two 32-byte numbers as well as a tag which
130 /// allows recovering the exact public key which created the signature given the message.
131 pub struct RecoverableSignature {
132 /// The bytes of the signature in "compact" form plus a "Recovery ID" which allows for
134 pub serialized_form: [u8; 68],
136 impl RecoverableSignature {
137 pub(crate) fn from_rust(pk: &SecpRecoverableSignature) -> Self {
138 let (id, compact_form) = pk.serialize_compact();
139 let mut serialized_form = [0; 68];
140 serialized_form[0..64].copy_from_slice(&compact_form[..]);
141 serialized_form[64..].copy_from_slice(&id.to_i32().to_le_bytes());
142 Self { serialized_form }
144 pub(crate) fn into_rust(&self) -> SecpRecoverableSignature {
146 id.copy_from_slice(&self.serialized_form[64..]);
147 SecpRecoverableSignature::from_compact(&self.serialized_form[0..64],
148 RecoveryId::from_i32(i32::from_le_bytes(id)).expect("Invalid Recovery ID"))
155 /// Represents a scalar value between zero and the secp256k1 curve order, in big endian.
156 pub struct BigEndianScalar {
157 /// The bytes of the scalar value.
158 pub big_endian_bytes: [u8; 32],
160 impl BigEndianScalar {
161 pub(crate) fn from_rust(scalar: &SecpScalar) -> Self {
162 Self { big_endian_bytes: scalar.to_be_bytes() }
164 pub(crate) fn into_rust(&self) -> SecpScalar {
165 SecpScalar::from_be_bytes(self.big_endian_bytes).expect("Scalar greater than the curve order")
170 /// Convenience function for constructing a new BigEndianScalar
171 pub extern "C" fn BigEndianScalar_new(big_endian_bytes: ThirtyTwoBytes) -> BigEndianScalar {
172 BigEndianScalar { big_endian_bytes: big_endian_bytes.data }
176 #[derive(Copy, Clone)]
177 /// Represents an error returned from libsecp256k1 during validation of some secp256k1 data
178 pub enum Secp256k1Error {
179 /// Signature failed verification
181 /// Badly sized message ("messages" are actually fixed-sized digests; see the MESSAGE_SIZE constant)
189 /// Bad shared secret.
193 /// Invalid tweak for add_assign or mul_assign
195 /// Didn't pass enough memory to context creation with preallocated memory
197 /// Bad set of public keys.
199 /// The only valid parity values are 0 or 1.
202 impl Secp256k1Error {
203 pub(crate) fn from_rust(err: SecpError) -> Self {
205 SecpError::IncorrectSignature => Secp256k1Error::IncorrectSignature,
206 SecpError::InvalidMessage => Secp256k1Error::InvalidMessage,
207 SecpError::InvalidPublicKey => Secp256k1Error::InvalidPublicKey,
208 SecpError::InvalidSignature => Secp256k1Error::InvalidSignature,
209 SecpError::InvalidSecretKey => Secp256k1Error::InvalidSecretKey,
210 SecpError::InvalidSharedSecret => Secp256k1Error::InvalidSharedSecret,
211 SecpError::InvalidRecoveryId => Secp256k1Error::InvalidRecoveryId,
212 SecpError::InvalidTweak => Secp256k1Error::InvalidTweak,
213 SecpError::NotEnoughMemory => Secp256k1Error::NotEnoughMemory,
214 SecpError::InvalidPublicKeySum => Secp256k1Error::InvalidPublicKeySum,
215 SecpError::InvalidParityValue(_) => Secp256k1Error::InvalidParityValue,
218 pub(crate) fn into_rust(self) -> SecpError {
219 let invalid_parity = secp256k1::Parity::from_i32(42).unwrap_err();
221 Secp256k1Error::IncorrectSignature => SecpError::IncorrectSignature,
222 Secp256k1Error::InvalidMessage => SecpError::InvalidMessage,
223 Secp256k1Error::InvalidPublicKey => SecpError::InvalidPublicKey,
224 Secp256k1Error::InvalidSignature => SecpError::InvalidSignature,
225 Secp256k1Error::InvalidSecretKey => SecpError::InvalidSecretKey,
226 Secp256k1Error::InvalidSharedSecret => SecpError::InvalidSharedSecret,
227 Secp256k1Error::InvalidRecoveryId => SecpError::InvalidRecoveryId,
228 Secp256k1Error::InvalidTweak => SecpError::InvalidTweak,
229 Secp256k1Error::NotEnoughMemory => SecpError::NotEnoughMemory,
230 Secp256k1Error::InvalidPublicKeySum => SecpError::InvalidPublicKeySum,
231 Secp256k1Error::InvalidParityValue => SecpError::InvalidParityValue(invalid_parity),
237 #[derive(Copy, Clone)]
238 /// Represents an error returned from the bech32 library during validation of some bech32 data
239 pub enum Bech32Error {
240 /// String does not contain the separator character
242 /// The checksum does not match the rest of the data
244 /// The data or human-readable part is too long or too short
246 /// Some part of the string contains an invalid character
248 /// Some part of the data has an invalid value
250 /// The bit conversion failed due to a padding issue
252 /// The whole string must be of one case
256 pub(crate) fn from_rust(err: bech32::Error) -> Self {
258 bech32::Error::MissingSeparator => Self::MissingSeparator,
259 bech32::Error::InvalidChecksum => Self::InvalidChecksum,
260 bech32::Error::InvalidLength => Self::InvalidLength,
261 bech32::Error::InvalidChar(c) => Self::InvalidChar(c as u32),
262 bech32::Error::InvalidData(d) => Self::InvalidData(d),
263 bech32::Error::InvalidPadding => Self::InvalidPadding,
264 bech32::Error::MixedCase => Self::MixedCase,
267 pub(crate) fn into_rust(self) -> bech32::Error {
269 Self::MissingSeparator => bech32::Error::MissingSeparator,
270 Self::InvalidChecksum => bech32::Error::InvalidChecksum,
271 Self::InvalidLength => bech32::Error::InvalidLength,
272 Self::InvalidChar(c) => bech32::Error::InvalidChar(core::char::from_u32(c).expect("Invalid UTF-8 character in Bech32Error::InvalidChar")),
273 Self::InvalidData(d) => bech32::Error::InvalidData(d),
274 Self::InvalidPadding => bech32::Error::InvalidPadding,
275 Self::MixedCase => bech32::Error::MixedCase,
280 /// Creates a new Bech32Error which has the same data as `orig`
281 pub extern "C" fn Bech32Error_clone(orig: &Bech32Error) -> Bech32Error { orig.clone() }
283 /// Releases any memory held by the given `Bech32Error` (which is currently none)
284 pub extern "C" fn Bech32Error_free(o: Bech32Error) { }
287 #[derive(Clone, Copy, PartialEq)]
288 /// Sub-errors which don't have specific information in them use this type.
290 /// Zero-Sized_types aren't consistent across Rust/C/C++, so we add some size here
295 #[allow(missing_docs)] // If there's no docs upstream, that's good enough for us
296 #[derive(Clone, Copy, PartialEq)]
297 /// Represents an IO Error. Note that some information is lost in the conversion from Rust.
319 pub(crate) fn from_rust_kind(err: io::ErrorKind) -> Self {
321 io::ErrorKind::NotFound => IOError::NotFound,
322 io::ErrorKind::PermissionDenied => IOError::PermissionDenied,
323 io::ErrorKind::ConnectionRefused => IOError::ConnectionRefused,
324 io::ErrorKind::ConnectionReset => IOError::ConnectionReset,
325 io::ErrorKind::ConnectionAborted => IOError::ConnectionAborted,
326 io::ErrorKind::NotConnected => IOError::NotConnected,
327 io::ErrorKind::AddrInUse => IOError::AddrInUse,
328 io::ErrorKind::AddrNotAvailable => IOError::AddrNotAvailable,
329 io::ErrorKind::BrokenPipe => IOError::BrokenPipe,
330 io::ErrorKind::AlreadyExists => IOError::AlreadyExists,
331 io::ErrorKind::WouldBlock => IOError::WouldBlock,
332 io::ErrorKind::InvalidInput => IOError::InvalidInput,
333 io::ErrorKind::InvalidData => IOError::InvalidData,
334 io::ErrorKind::TimedOut => IOError::TimedOut,
335 io::ErrorKind::WriteZero => IOError::WriteZero,
336 io::ErrorKind::Interrupted => IOError::Interrupted,
337 io::ErrorKind::Other => IOError::Other,
338 io::ErrorKind::UnexpectedEof => IOError::UnexpectedEof,
342 pub(crate) fn from_rust(err: io::Error) -> Self {
343 Self::from_rust_kind(err.kind())
345 pub(crate) fn to_rust_kind(&self) -> io::ErrorKind {
347 IOError::NotFound => io::ErrorKind::NotFound,
348 IOError::PermissionDenied => io::ErrorKind::PermissionDenied,
349 IOError::ConnectionRefused => io::ErrorKind::ConnectionRefused,
350 IOError::ConnectionReset => io::ErrorKind::ConnectionReset,
351 IOError::ConnectionAborted => io::ErrorKind::ConnectionAborted,
352 IOError::NotConnected => io::ErrorKind::NotConnected,
353 IOError::AddrInUse => io::ErrorKind::AddrInUse,
354 IOError::AddrNotAvailable => io::ErrorKind::AddrNotAvailable,
355 IOError::BrokenPipe => io::ErrorKind::BrokenPipe,
356 IOError::AlreadyExists => io::ErrorKind::AlreadyExists,
357 IOError::WouldBlock => io::ErrorKind::WouldBlock,
358 IOError::InvalidInput => io::ErrorKind::InvalidInput,
359 IOError::InvalidData => io::ErrorKind::InvalidData,
360 IOError::TimedOut => io::ErrorKind::TimedOut,
361 IOError::WriteZero => io::ErrorKind::WriteZero,
362 IOError::Interrupted => io::ErrorKind::Interrupted,
363 IOError::Other => io::ErrorKind::Other,
364 IOError::UnexpectedEof => io::ErrorKind::UnexpectedEof,
367 pub(crate) fn to_rust(&self) -> io::Error {
368 io::Error::new(self.to_rust_kind(), "")
373 /// A serialized transaction, in (pointer, length) form.
375 /// This type optionally owns its own memory, and thus the semantics around access change based on
376 /// the `data_is_owned` flag. If `data_is_owned` is set, you must call `Transaction_free` to free
377 /// the underlying buffer before the object goes out of scope. If `data_is_owned` is not set, any
378 /// access to the buffer after the scope in which the object was provided to you is invalid. eg,
379 /// access after you return from the call in which a `!data_is_owned` `Transaction` is provided to
380 /// you would be invalid.
382 /// Note that, while it may change in the future, because transactions on the Rust side are stored
383 /// in a deserialized form, all `Transaction`s generated on the Rust side will have `data_is_owned`
384 /// set. Similarly, while it may change in the future, all `Transaction`s you pass to Rust may have
385 /// `data_is_owned` either set or unset at your discretion.
386 pub struct Transaction {
387 /// The serialized transaction data.
389 /// This is non-const for your convenience, an object passed to Rust is never written to.
391 /// The length of the serialized transaction
393 /// Whether the data pointed to by `data` should be freed or not.
394 pub data_is_owned: bool,
397 fn from_vec(vec: Vec<u8>) -> Self {
398 let datalen = vec.len();
399 let data = Box::into_raw(vec.into_boxed_slice());
401 data: unsafe { (*data).as_mut_ptr() },
406 pub(crate) fn into_bitcoin(&self) -> BitcoinTransaction {
407 if self.datalen == 0 { panic!("0-length buffer can never represent a valid Transaction"); }
408 ::bitcoin::consensus::encode::deserialize(unsafe { core::slice::from_raw_parts(self.data, self.datalen) }).unwrap()
410 pub(crate) fn from_bitcoin(btc: &BitcoinTransaction) -> Self {
411 let vec = ::bitcoin::consensus::encode::serialize(btc);
415 impl Drop for Transaction {
417 if self.data_is_owned && self.datalen != 0 {
418 let _ = derived::CVec_u8Z { data: self.data as *mut u8, datalen: self.datalen };
422 impl Clone for Transaction {
423 fn clone(&self) -> Self {
424 let sl = unsafe { core::slice::from_raw_parts(self.data, self.datalen) };
425 let mut v = Vec::new();
426 v.extend_from_slice(&sl);
431 /// Frees the data buffer, if data_is_owned is set and datalen > 0.
432 pub extern "C" fn Transaction_free(_res: Transaction) { }
434 pub(crate) fn bitcoin_to_C_outpoint(outpoint: ::bitcoin::blockdata::transaction::OutPoint) -> crate::lightning::chain::transaction::OutPoint {
435 crate::lightning::chain::transaction::OutPoint_new(ThirtyTwoBytes { data: outpoint.txid.into_inner() }, outpoint.vout.try_into().unwrap())
437 pub(crate) fn C_to_bitcoin_outpoint(outpoint: crate::lightning::chain::transaction::OutPoint) -> ::bitcoin::blockdata::transaction::OutPoint {
439 ::bitcoin::blockdata::transaction::OutPoint {
440 txid: (*outpoint.inner).txid, vout: (*outpoint.inner).index as u32
447 /// A transaction output including a scriptPubKey and value.
448 /// This type *does* own its own memory, so must be free'd appropriately.
450 /// The script_pubkey in this output
451 pub script_pubkey: derived::CVec_u8Z,
452 /// The value, in satoshis, of this output
457 pub(crate) fn into_rust(mut self) -> ::bitcoin::blockdata::transaction::TxOut {
458 ::bitcoin::blockdata::transaction::TxOut {
459 script_pubkey: self.script_pubkey.into_rust().into(),
463 pub(crate) fn from_rust(txout: ::bitcoin::blockdata::transaction::TxOut) -> Self {
465 script_pubkey: derived::CVec_u8Z::from(txout.script_pubkey.into_bytes()),
472 /// Convenience function for constructing a new TxOut
473 pub extern "C" fn TxOut_new(script_pubkey: derived::CVec_u8Z, value: u64) -> TxOut {
474 TxOut { script_pubkey, value }
477 /// Frees the data pointed to by script_pubkey.
478 pub extern "C" fn TxOut_free(_res: TxOut) { }
480 /// Creates a new TxOut which has the same data as `orig` but with a new script buffer.
481 pub extern "C" fn TxOut_clone(orig: &TxOut) -> TxOut { orig.clone() }
484 /// A "slice" referencing some byte array. This is simply a length-tagged pointer which does not
485 /// own the memory pointed to by data.
487 /// A pointer to the byte buffer
489 /// The number of bytes pointed to by `data`.
493 pub(crate) fn from_slice(s: &[u8]) -> Self {
499 pub(crate) fn to_slice(&self) -> &[u8] {
500 if self.datalen == 0 { return &[]; }
501 unsafe { core::slice::from_raw_parts(self.data, self.datalen) }
503 pub(crate) fn to_reader<'a>(&'a self) -> Cursor<&'a [u8]> {
504 let sl = self.to_slice();
507 pub(crate) fn from_vec(v: &derived::CVec_u8Z) -> u8slice {
508 Self::from_slice(v.as_slice())
511 pub(crate) fn reader_to_vec<R: Read>(r: &mut R) -> derived::CVec_u8Z {
512 let mut res = Vec::new();
513 r.read_to_end(&mut res).unwrap();
514 derived::CVec_u8Z::from(res)
518 #[derive(Copy, Clone)]
519 /// Arbitrary 32 bytes, which could represent one of a few different things. You probably want to
520 /// look up the corresponding function in rust-lightning's docs.
521 pub struct ThirtyTwoBytes {
522 /// The thirty-two bytes
525 impl ThirtyTwoBytes {
526 pub(crate) fn null() -> Self {
527 Self { data: [0; 32] }
532 /// A 3-byte byte array.
533 pub struct ThreeBytes { /** The three bytes */ pub data: [u8; 3], }
536 /// A 4-byte byte array.
537 pub struct FourBytes { /** The four bytes */ pub data: [u8; 4], }
540 /// A 12-byte byte array.
541 pub struct TwelveBytes { /** The twelve bytes */ pub data: [u8; 12], }
544 /// A 16-byte byte array.
545 pub struct SixteenBytes { /** The sixteen bytes */ pub data: [u8; 16], }
548 /// A 20-byte byte array.
549 pub struct TwentyBytes { /** The twenty bytes */ pub data: [u8; 20], }
551 pub(crate) struct VecWriter(pub Vec<u8>);
552 impl lightning::util::ser::Writer for VecWriter {
553 fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
554 self.0.extend_from_slice(buf);
558 pub(crate) fn serialize_obj<I: lightning::util::ser::Writeable>(i: &I) -> derived::CVec_u8Z {
559 let mut out = VecWriter(Vec::new());
560 i.write(&mut out).unwrap();
561 derived::CVec_u8Z::from(out.0)
563 pub(crate) fn deserialize_obj<I: lightning::util::ser::Readable>(s: u8slice) -> Result<I, lightning::ln::msgs::DecodeError> {
564 I::read(&mut s.to_slice())
566 pub(crate) fn maybe_deserialize_obj<I: lightning::util::ser::MaybeReadable>(s: u8slice) -> Result<Option<I>, lightning::ln::msgs::DecodeError> {
567 I::read(&mut s.to_slice())
569 pub(crate) fn deserialize_obj_arg<A, I: lightning::util::ser::ReadableArgs<A>>(s: u8slice, args: A) -> Result<I, lightning::ln::msgs::DecodeError> {
570 I::read(&mut s.to_slice(), args)
574 /// A Rust str object, ie a reference to a UTF8-valid string.
575 /// This is *not* null-terminated so cannot be used directly as a C string!
577 /// A pointer to the string's bytes, in UTF8 encoding
578 pub chars: *const u8,
579 /// The number of bytes (not characters!) pointed to by `chars`
581 /// Whether the data pointed to by `chars` should be freed or not.
582 pub chars_is_owned: bool,
584 impl Into<Str> for &'static str {
585 fn into(self) -> Str {
586 Str { chars: self.as_ptr(), len: self.len(), chars_is_owned: false }
589 impl Into<Str> for &mut &'static str {
590 fn into(self) -> Str {
591 let us: &'static str = *self;
597 pub(crate) fn into_str(&self) -> &'static str {
598 if self.len == 0 { return ""; }
599 core::str::from_utf8(unsafe { core::slice::from_raw_parts(self.chars, self.len) }).unwrap()
601 pub(crate) fn into_string(mut self) -> String {
602 let bytes = if self.len == 0 {
604 } else if self.chars_is_owned {
606 Box::from_raw(core::slice::from_raw_parts_mut(unsafe { self.chars as *mut u8 }, self.len))
608 self.chars_is_owned = false;
611 let mut ret = Vec::with_capacity(self.len);
612 ret.extend_from_slice(unsafe { core::slice::from_raw_parts(self.chars, self.len) });
615 String::from_utf8(bytes).unwrap()
618 impl Into<Str> for String {
619 fn into(self) -> Str {
620 let s = Box::leak(self.into_boxed_str());
621 Str { chars: s.as_ptr(), len: s.len(), chars_is_owned: true }
625 fn clone(&self) -> Self {
626 String::from(self.into_str()).into()
632 if self.chars_is_owned && self.len != 0 {
633 let _ = derived::CVec_u8Z { data: self.chars as *mut u8, datalen: self.len };
638 /// Frees the data buffer, if chars_is_owned is set and len > 0.
639 pub extern "C" fn Str_free(_res: Str) { }
641 // Note that the C++ headers memset(0) all the Templ types to avoid deallocation!
642 // Thus, they must gracefully handle being completely null in _free.
644 // TODO: Integer/bool primitives should avoid the pointer indirection for underlying types
645 // everywhere in the containers.
648 pub(crate) union CResultPtr<O, E> {
649 pub(crate) result: *mut O,
650 pub(crate) err: *mut E,
653 pub(crate) struct CResultTempl<O, E> {
654 pub(crate) contents: CResultPtr<O, E>,
655 pub(crate) result_ok: bool,
657 impl<O, E> CResultTempl<O, E> {
658 pub(crate) extern "C" fn ok(o: O) -> Self {
660 contents: CResultPtr {
661 result: Box::into_raw(Box::new(o)),
666 pub(crate) extern "C" fn err(e: E) -> Self {
668 contents: CResultPtr {
669 err: Box::into_raw(Box::new(e)),
675 impl<O, E> Drop for CResultTempl<O, E> {
678 if unsafe { !self.contents.result.is_null() } {
679 let _ = unsafe { Box::from_raw(self.contents.result) };
681 } else if unsafe { !self.contents.err.is_null() } {
682 let _ = unsafe { Box::from_raw(self.contents.err) };
687 /// Utility to make it easy to set a pointer to null and get its original value in line.
688 pub(crate) trait TakePointer<T> {
689 fn take_ptr(&mut self) -> T;
691 impl<T> TakePointer<*const T> for *const T {
692 fn take_ptr(&mut self) -> *const T {
694 *self = core::ptr::null();
698 impl<T> TakePointer<*mut T> for *mut T {
699 fn take_ptr(&mut self) -> *mut T {
701 *self = core::ptr::null_mut();
707 pub(crate) mod ObjOps {
708 #[cfg(feature = "no-std")]
709 use alloc::boxed::Box;
712 #[must_use = "returns new dangling pointer"]
713 pub(crate) fn heap_alloc<T>(obj: T) -> *mut T {
714 let ptr = Box::into_raw(Box::new(obj));
715 nonnull_ptr_to_inner(ptr)
718 pub(crate) fn nonnull_ptr_to_inner<T>(ptr: *const T) -> *mut T {
719 if core::mem::size_of::<T>() == 0 {
720 // We map `None::<T>` as `T { inner: null, .. }` which works great for all
721 // non-Zero-Sized-Types `T`.
722 // For ZSTs, we need to differentiate between null implying `None` and null implying
723 // `Some` with no allocation.
724 // Thus, for ZSTs, we add one (usually) page here, which should always be aligned.
725 // Note that this relies on undefined behavior! A pointer to NULL may be valid, but a
726 // pointer to NULL + 4096 is almost certainly not. That said, Rust's existing use of
727 // `(*mut T)1` for the pointer we're adding to is also not defined, so we should be
729 // Note that we add 4095 here as at least the Java client assumes that the low bit on
730 // any heap pointer is 0, which is generally provided by malloc, but which is not true
731 // for ZSTs "allocated" by `Box::new`.
732 debug_assert_eq!(ptr as usize, 1);
733 unsafe { (ptr as *mut T).cast::<u8>().add(4096 - 1).cast::<T>() }
735 // In order to get better test coverage, also increment non-ZST pointers with
736 // --cfg=test_mod_pointers, which is set in genbindings.sh for debug builds.
737 #[cfg(test_mod_pointers)]
738 unsafe { (ptr as *mut T).cast::<u8>().add(4096).cast::<T>() }
739 #[cfg(not(test_mod_pointers))]
740 unsafe { ptr as *mut T }
744 /// Invert nonnull_ptr_to_inner
745 pub(crate) fn untweak_ptr<T>(ptr: *mut T) -> *mut T {
746 if core::mem::size_of::<T>() == 0 {
747 unsafe { ptr.cast::<u8>().sub(4096 - 1).cast::<T>() }
749 #[cfg(test_mod_pointers)]
750 unsafe { ptr.cast::<u8>().sub(4096).cast::<T>() }
751 #[cfg(not(test_mod_pointers))]
757 #[cfg(test_mod_pointers)]
759 /// This function exists for memory safety testing purposes. It should never be used in production
761 pub extern "C" fn __unmangle_inner_ptr(ptr: *const c_void) -> *const c_void {
762 if ptr as usize == 1 {
765 unsafe { ptr.cast::<u8>().sub(4096).cast::<c_void>() }
769 pub(crate) struct SmartPtr<T> {
772 impl<T> SmartPtr<T> {
773 pub(crate) fn from_obj(o: T) -> Self {
774 Self { ptr: Box::into_raw(Box::new(o)) }
776 pub(crate) fn null() -> Self {
777 Self { ptr: core::ptr::null_mut() }
780 impl<T> Drop for SmartPtr<T> {
782 if self.ptr != core::ptr::null_mut() {
783 let _ = unsafe { Box::from_raw(self.ptr) };
787 impl<T> core::ops::Deref for SmartPtr<T> {
788 type Target = *mut T;
789 fn deref(&self) -> &*mut T {