Move more things from the std feature to the alloc feature

Author: elichai

Cargo.toml

@@ -20,10 +20,10 @@ rustdoc-args = ["--cfg", "docsrs"]
 [features]
 unstable = ["recovery", "rand-std"]
 default = ["std"]
-std = ["secp256k1-sys/std"]
+std = ["alloc", "secp256k1-sys/std"]
 # allow use of Secp256k1::new and related API that requires an allocator
-alloc = []
-bitcoin-hashes-std = ["bitcoin_hashes/std"]
+ alloc = ["secp256k1-sys/alloc"]
+ bitcoin-hashes-std = ["bitcoin_hashes/std"]
 rand-std = ["rand/std"]
 recovery = ["secp256k1-sys/recovery"]
 lowmemory = ["secp256k1-sys/lowmemory"]

secp256k1-sys/Cargo.toml

@@ -30,5 +30,6 @@ libc = "0.2"
 default = ["std"]
 recovery = []
 lowmemory = []
-std = []
+std = ["alloc"]
+alloc = []
 

secp256k1-sys/src/lib.rs

@@ -25,6 +25,9 @@
 #[cfg(any(test, feature = "std"))]
 extern crate core;
 
+#[cfg(feature = "alloc")]
+extern crate alloc;
+
 #[cfg(fuzzing)]
 const THIS_UNUSED_CONSTANT_IS_YOUR_WARNING_THAT_ALL_THE_CRYPTO_IN_THIS_LIB_IS_DISABLED_FOR_FUZZING: usize = 0;
 
@@ -540,11 +543,11 @@ extern "C" {
 ///
 /// The newly created secp256k1 raw context.
 #[no_mangle]
-#[cfg(all(feature = "std", not(rust_secp_no_symbol_renaming)))]
-#[cfg_attr(docsrs, doc(cfg(all(feature = "std", not(rust_secp_no_symbol_renaming)))))]
+#[cfg(all(feature = "alloc", not(rust_secp_no_symbol_renaming)))]
+#[cfg_attr(docsrs, doc(cfg(all(feature = "alloc", not(rust_secp_no_symbol_renaming)))))]
 pub unsafe extern "C" fn rustsecp256k1_v0_5_0_context_create(flags: c_uint) -> *mut Context {
     use core::mem;
-    use std::alloc;
+    use crate::alloc::alloc;
     assert!(ALIGN_TO >= mem::align_of::<usize>());
     assert!(ALIGN_TO >= mem::align_of::<&usize>());
     assert!(ALIGN_TO >= mem::size_of::<usize>());
@@ -560,8 +563,8 @@ pub unsafe extern "C" fn rustsecp256k1_v0_5_0_context_create(flags: c_uint) -> *
     secp256k1_context_preallocated_create(ptr, flags)
 }
 
-#[cfg(all(feature = "std", not(rust_secp_no_symbol_renaming)))]
-#[cfg_attr(docsrs, doc(cfg(all(feature = "std", not(rust_secp_no_symbol_renaming)))))]
+#[cfg(all(feature = "alloc", not(rust_secp_no_symbol_renaming)))]
+#[cfg_attr(docsrs, doc(cfg(all(feature = "alloc", not(rust_secp_no_symbol_renaming)))))]
 pub unsafe fn secp256k1_context_create(flags: c_uint) -> *mut Context {
     rustsecp256k1_v0_5_0_context_create(flags)
 }
@@ -573,19 +576,19 @@ pub unsafe fn secp256k1_context_create(flags: c_uint) -> *mut Context {
 /// The pointer shouldn't be used after passing to this function, consider it as passing it to `free()`.
 ///
 #[no_mangle]
-#[cfg(all(feature = "std", not(rust_secp_no_symbol_renaming)))]
-#[cfg_attr(docsrs, doc(cfg(all(feature = "std", not(rust_secp_no_symbol_renaming)))))]
+#[cfg(all(feature = "alloc", not(rust_secp_no_symbol_renaming)))]
+#[cfg_attr(docsrs, doc(cfg(all(feature = "alloc", not(rust_secp_no_symbol_renaming)))))]
 pub unsafe extern "C" fn rustsecp256k1_v0_5_0_context_destroy(ctx: *mut Context) {
-    use std::alloc;
+    use crate::alloc::alloc;
     secp256k1_context_preallocated_destroy(ctx);
     let ptr = (ctx as *mut u8).sub(ALIGN_TO);
     let bytes = (ptr as *mut usize).read();
     let layout = alloc::Layout::from_size_align(bytes, ALIGN_TO).unwrap();
     alloc::dealloc(ptr, layout);
 }
 
-#[cfg(all(feature = "std", not(rust_secp_no_symbol_renaming)))]
-#[cfg_attr(docsrs, doc(cfg(all(feature = "std", not(rust_secp_no_symbol_renaming)))))]
+#[cfg(all(feature = "alloc", not(rust_secp_no_symbol_renaming)))]
+#[cfg_attr(docsrs, doc(cfg(all(feature = "alloc", not(rust_secp_no_symbol_renaming)))))]
 pub unsafe fn secp256k1_context_destroy(ctx: *mut Context) {
     rustsecp256k1_v0_5_0_context_destroy(ctx)
 }

secp256k1-sys/src/types.rs

@@ -28,7 +28,7 @@ impl AlignedType {
     pub const ZERO: AlignedType = AlignedType([0u8; 16]);
 }
 
-#[cfg(all(feature = "std", not(rust_secp_no_symbol_renaming)))]
+#[cfg(all(feature = "alloc", not(rust_secp_no_symbol_renaming)))]
 pub(crate) const ALIGN_TO: usize = core::mem::align_of::<AlignedType>();
 
 #[cfg(test)]

src/context.rs

@@ -5,8 +5,8 @@ use crate::{Error, Secp256k1};
 use crate::ffi::{self, CPtr, types::AlignedType};
 use crate::ffi::types::{c_uint, c_void};
 
-#[cfg(any(feature = "std", feature = "alloc"))]
-#[cfg_attr(docsrs, doc(cfg(any(feature = "std", feature = "alloc"))))]
+#[cfg(feature = "alloc")]
+#[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 pub use self::alloc_only::*;
 
 #[cfg(all(feature = "global-context", feature = "std"))]
@@ -103,13 +103,10 @@ mod private {
     impl<'buf> Sealed for SignOnlyPreallocated<'buf> {}
 }
 
-#[cfg(any(feature = "std", feature = "alloc"))]
-#[cfg_attr(docsrs, doc(cfg(any(feature = "std", feature = "alloc"))))]
+#[cfg(feature = "alloc")]
+#[cfg_attr(docsrs, doc(cfg(any(feature = "alloc"))))]
 mod alloc_only {
-    #[cfg(not(feature = "std"))]
-    use alloc::alloc;
-    #[cfg(feature = "std")]
-    use std::alloc;
+    use crate::alloc::alloc;
 
     use core::marker::PhantomData;