From 276d1f3f2012efeb24ed0f021b274b79474a5410 Mon Sep 17 00:00:00 2001
From: Simon Gardling <titaniumtown@gmail.com>
Date: Fri, 20 May 2022 12:37:48 -0400
Subject: [PATCH] improve hashed_storage_read

---
 src/math_app.rs | 6 +++---
 src/misc.rs     | 9 +++------
 tests/misc.rs   | 9 ++++++---
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/src/math_app.rs b/src/math_app.rs
index 113387d..483c5b0 100644
--- a/src/math_app.rs
+++ b/src/math_app.rs
@@ -145,7 +145,7 @@ impl MathApp {
 
 				fn get_storage_decompressed() -> Option<Vec<u8>> {
 					let data = get_localstorage().get_item(DATA_NAME).ok()??;
-					let (commit, cached_data) = crate::misc::hashed_storage_read(data)?;
+					let (commit, cached_data) = crate::misc::hashed_storage_read(&data)?;
 
 					debug_assert!(!commit.is_empty());
 					debug_assert!(!cached_data.is_empty());
@@ -183,7 +183,7 @@ impl MathApp {
 						return None;
 					}
 
-					let (commit, func_data) = crate::misc::hashed_storage_read(data)?;
+					let (commit, func_data) = crate::misc::hashed_storage_read(&data)?;
 
 					debug_assert!(!commit.is_empty());
 					debug_assert!(!func_data.is_empty());
@@ -193,7 +193,7 @@ impl MathApp {
 						assume(!func_data.is_empty());
 					}
 
-					if commit == build::SHORT_COMMIT.chars().map(|c| c as u8).collect::<Vec<u8>>().as_slice() {
+					if commit == unsafe { std::mem::transmute::<&str, &[u8]>(build::SHORT_COMMIT) } {
 						tracing::info!("Reading previous function data");
 						let function_manager: FunctionManager = bincode::deserialize(&func_data).ok()?;
 						return Some(function_manager);
diff --git a/src/misc.rs b/src/misc.rs
index f58dbcf..765ce3b 100644
--- a/src/misc.rs
+++ b/src/misc.rs
@@ -337,7 +337,7 @@ pub fn hashed_storage_create(hash: HashBytes, data: &[u8]) -> String {
 }
 
 #[allow(dead_code)]
-pub fn hashed_storage_read(data: String) -> Option<(HashBytes, Vec<u8>)> {
+pub const fn hashed_storage_read(data: &str) -> Option<(HashBytes, &[u8])> {
 	if HASH_LENGTH >= data.len() {
 		return None;
 	}
@@ -347,12 +347,9 @@ pub fn hashed_storage_read(data: String) -> Option<(HashBytes, Vec<u8>)> {
 		assume(data.len() > HASH_LENGTH);
 	}
 
-	let decoded_1: Vec<u8> = unsafe { std::mem::transmute::<String, Vec<u8>>(data) };
+	let decoded_1: &[u8] = unsafe { std::mem::transmute::<&str, &[u8]>(data) };
 
 	let hash: HashBytes = unsafe { *(decoded_1[..HASH_LENGTH].as_ptr() as *const HashBytes) };
-	let cached_data = decoded_1[HASH_LENGTH..].to_vec();
 
-	debug_assert!(!cached_data.is_empty());
-
-	Some((hash, cached_data))
+	Some((hash, &decoded_1[HASH_LENGTH..]))
 }
diff --git a/tests/misc.rs b/tests/misc.rs
index 250c87e..8e8a169 100644
--- a/tests/misc.rs
+++ b/tests/misc.rs
@@ -105,14 +105,17 @@ fn hashed_storage() {
 		data.as_slice(),
 	);
 
-	let read = hashed_storage_read(storage);
-	assert_eq!(read.map(|(a, b)| (a.to_vec(), b)), Some((commit, data)));
+	let read = hashed_storage_read(&storage);
+	assert_eq!(
+		read.map(|(a, b)| (a.to_vec(), b.to_vec())),
+		Some((commit.to_vec(), data.to_vec()))
+	);
 }
 
 #[test]
 fn invalid_hashed_storage() {
 	use ytbn_graphing_software::hashed_storage_read;
-	assert_eq!(hashed_storage_read("aaaa".to_owned()), None);
+	assert_eq!(hashed_storage_read("aaaa"), None);
 }
 
 #[test]