Drop the now-unused usizeslice bindings struct

[rust-lightning] / lightning-c-bindings / src / c_types / mod.rs

diff --git a/lightning-c-bindings/src/c_types/mod.rs b/lightning-c-bindings/src/c_types/mod.rs
index be697d49639d2650b1e4dd9ee2ae57ad730f4128..813e401b8e7e2b5f567b8791117c815c02aa0d61 100644 (file)
--- a/lightning-c-bindings/src/c_types/mod.rs
+++ b/lightning-c-bindings/src/c_types/mod.rs
@@ -86,25 +86,48 @@ impl Secp256k1Error {
 }
 
 #[repr(C)]
-/// A reference to a serialized transaction, in (pointer, length) form.
-/// This type does *not* own its own memory, so access to it after, eg, the call in which it was
-/// provided to you are invalid.
+/// A serialized transaction, in (pointer, length) form.
+///
+/// This type optionally owns its own memory, and thus the semantics around access change based on
+/// the `data_is_owned` flag. If `data_is_owned` is set, you must call `Transaction_free` to free
+/// the underlying buffer before the object goes out of scope. If `data_is_owned` is not set, any
+/// access to the buffer after the scope in which the object was provided to you is invalid. eg,
+/// access after you return from the call in which a `!data_is_owned` `Transaction` is provided to
+/// you would be invalid.
+///
+/// Note that, while it may change in the future, because transactions on the Rust side are stored
+/// in a deserialized form, all `Transaction`s generated on the Rust side will have `data_is_owned`
+/// set. Similarly, while it may change in the future, all `Transaction`s you pass to Rust may have
+/// `data_is_owned` either set or unset at your discretion.
 pub struct Transaction {
        pub data: *const u8,
        pub datalen: usize,
+       pub data_is_owned: bool,
 }
 impl Transaction {
        pub(crate) fn into_bitcoin(&self) -> BitcoinTransaction {
                if self.datalen == 0 { panic!("0-length buffer can never represent a valid Transaction"); }
                ::bitcoin::consensus::encode::deserialize(unsafe { std::slice::from_raw_parts(self.data, self.datalen) }).unwrap()
        }
-       pub(crate) fn from_slice(s: &[u8]) -> Self {
+       pub(crate) fn from_vec(v: Vec<u8>) -> Self {
+               let datalen = v.len();
+               let data = Box::into_raw(v.into_boxed_slice());
                Self {
-                       data: s.as_ptr(),
-                       datalen: s.len(),
+                       data: unsafe { (*data).as_mut_ptr() },
+                       datalen,
+                       data_is_owned: true,
+               }
+       }
+}
+impl Drop for Transaction {
+       fn drop(&mut self) {
+               if self.data_is_owned && self.datalen != 0 {
+                       let _ = CVecTempl { data: self.data as *mut u8, datalen: self.datalen };
                }
        }
 }
+#[no_mangle]
+pub extern "C" fn Transaction_free(_res: Transaction) { }
 
 #[repr(C)]
 #[derive(Clone)]
@@ -150,24 +173,6 @@ impl u8slice {
        }
 }
 
-#[repr(C)]
-pub struct usizeslice {
-       pub data: *const usize,
-       pub datalen: usize
-}
-impl usizeslice {
-       pub(crate) fn from_slice(s: &[usize]) -> Self {
-               Self {
-                       data: s.as_ptr(),
-                       datalen: s.len(),
-               }
-       }
-       pub(crate) fn to_slice(&self) -> &[usize] {
-               if self.datalen == 0 { return &[]; }
-               unsafe { std::slice::from_raw_parts(self.data, self.datalen) }
-       }
-}
-
 #[repr(C)]
 #[derive(Copy, Clone)]
 /// Arbitrary 32 bytes, which could represent one of a few different things. You probably want to