Exposed generic functions to create the Context

src/context.rs

@@ -7,7 +7,7 @@ use Secp256k1;
 #[cfg(feature = "std")]
 pub use self::std_only::*;
 
-/// A trait for all kinds of Context's that let's you define the exact flags and a function to deallocate memory.
+/// A trait for all kinds of Context's that Lets you define the exact flags and a function to deallocate memory.
 /// * DO NOT * implement it for your own types.
 pub unsafe trait Context {
  /// Flags for the ffi.
@@ -86,7 +86,8 @@ mod std_only {
  }
 
  impl<C: Context> Secp256k1<C> {
- fn gen_new() -> Secp256k1<C> {
+ /// Lets you create a context in a generic manner(sign/verify/all)
+ pub fn gen_new() -> Secp256k1<C> {
  let buf = vec![0u8; Self::preallocate_size_gen()].into_boxed_slice();
  let ptr = Box::into_raw(buf);
  Secp256k1 {
@@ -148,31 +149,32 @@ unsafe impl<'buf> Context for SignOnlyPreallocated<'buf> {
  const FLAGS: c_uint = ffi::SECP256K1_START_SIGN;
  const DESCRIPTION: &'static str = "signing only";
 
- fn deallocate(ptr: *mut [u8]) {
- let _ = ptr;
+ fn deallocate(_ptr: *mut [u8]) {
+ // Allocated by the user
  }
 }
 
 unsafe impl<'buf> Context for VerifyOnlyPreallocated<'buf> {
  const FLAGS: c_uint = ffi::SECP256K1_START_VERIFY;
  const DESCRIPTION: &'static str = "verification only";
 
- fn deallocate(ptr: *mut [u8]) {
- let _ = ptr;
+ fn deallocate(_ptr: *mut [u8]) {
+ // Allocated by the user
  }
 }
 
 unsafe impl<'buf> Context for AllPreallocated<'buf> {
  const FLAGS: c_uint = SignOnlyPreallocated::FLAGS | VerifyOnlyPreallocated::FLAGS;
  const DESCRIPTION: &'static str = "all capabilities";
 
- fn deallocate(ptr: *mut [u8]) {
- let _ = ptr;
+ fn deallocate(_ptr: *mut [u8]) {
+ // Allocated by the user
  }
 }
 
 impl<'buf, C: Context + 'buf> Secp256k1<C> {
- fn preallocated_gen_new(buf: &'buf mut [u8]) -> Result<Secp256k1<C>, Error> {
+ /// Lets you create a context with preallocated buffer in a generic manner(sign/verify/all)
+ pub fn preallocated_gen_new(buf: &'buf mut [u8]) -> Result<Secp256k1<C>, Error> {
  if buf.len() < Self::preallocate_size_gen() {
  return Err(Error::NotEnoughMemory);
  }

src/lib.rs

@@ -570,8 +570,8 @@ impl<C: Context> Secp256k1<C> {
  &self.ctx
  }
 
- /// Uses the ffi `secp256k1_context_preallocated_size` to check the memory size needed for a context
- pub(crate) fn preallocate_size_gen() -> usize {
+ /// Returns the required memory for a preallocated context buffer in a generic manner(sign/verify/all)
+ pub fn preallocate_size_gen() -> usize {
  unsafe { ffi::secp256k1_context_preallocated_size(C::FLAGS) }
  }