sha256: added compute_slices()

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cryptohelpers"
-version = "1.6.0"
+version = "1.7.0"
 license= "MIT"
 description = "Collection of helpers and simplifying functions for cryptography things"
 authors = ["Avril <flanchan@cumallover.me>"]
@@ -20,10 +20,11 @@ libc = "0.2"
 tokio = {version = "0.2", features=["io-util"], optional=true}
 serde_derive = {version = "1.0", optional = true}
 serde = {version = "1.0", optional = true}
+futures = {version = "0.3.8", optional=true}
 
 [features]
 default = ["full", "async", "serialise"]
-async = ["tokio"]
+async = ["tokio", "futures"]
 
 # Actual things
 full = [

src/lib.rs

@@ -31,10 +31,14 @@ use serde_derive::{
 
 // Actual things
 
+#[cfg(feature="sha256")]
+pub use sha2;
 #[cfg(feature="sha256")] 
 pub mod sha256;
+
 #[cfg(feature="password")]
 pub mod password;
+
 #[cfg(feature="aes")]
 pub mod aes;
 #[cfg(feature="checksum")]

src/sha256.rs

@@ -135,6 +135,38 @@ where T: AsRef<[u8]>
     Sha256Hash{hash}
 }
 
+/// Compute a SHA256 hash from a stream of slices
+#[cfg(feature="async")]
+pub async fn compute_slices_stream<T, I>(mut from: I) -> Sha256Hash
+where I: futures::stream::Stream<Item=T> + std::marker::Unpin,
+      T: AsRef<[u8]>
+{
+    use futures::stream::StreamExt;
+    let mut hasher = Sha256::new();
+    while let Some(from) = from.next().await {
+	hasher.update(from.as_ref());
+    }
+
+    let mut hash = [0u8; SIZE];
+    bytes::copy_slice(&mut hash, &hasher.finalize());
+    Sha256Hash{hash}
+}
+
+/// Compute a SHA256 hash from a number of slices
+pub fn compute_slices<T, I>(from: I) -> Sha256Hash
+where I: IntoIterator<Item=T>,
+      T: AsRef<[u8]>
+{
+    let mut hasher = Sha256::new();
+    for from in from.into_iter() {
+	hasher.update(from.as_ref());
+    }
+
+    let mut hash = [0u8; SIZE];
+    bytes::copy_slice(&mut hash, &hasher.finalize());
+    Sha256Hash{hash}
+}
+
 
 /// Compute the SHA256 hash of the rest of this stream
 pub fn compute_sync<T>(from: &mut T) -> io::Result<Sha256Hash>