fix pow function

Author: YeahNotSewerSide

gen_test_data.py

@@ -0,0 +1,46 @@
+import hashlib
+import os
+
+
+def leading_zeros(num):
+    if num == 0:
+        return 8
+
+    leading_zeros = 0
+    while num & 0b10000000 == 0:
+        leading_zeros += 1
+        num = num << 1
+        num = num & 0b11111111
+    return leading_zeros
+
+
+def total_leading_zeros(hash):
+    to_return = 0
+    for byte in hash:
+        l_zeros = leading_zeros(byte)
+        to_return += l_zeros
+        if l_zeros < 8:
+            break
+
+    return to_return
+
+
+def gen(hash, difficulty):
+    difficulty = total_leading_zeros(difficulty)
+    for i in range(1000):
+        pow = b'' + os.urandom(10)
+        hasher = hashlib.sha256()
+        hasher.update(hash)
+        hasher.update(pow)
+
+        generated_hash = hasher.digest()
+        ghash_leadin_zeros = total_leading_zeros(generated_hash)
+
+        if ghash_leadin_zeros >= difficulty:
+            print(pow, True)
+        else:
+            print(pow, False)
+
+
+gen(hashlib.sha256(b'text').digest(),
+    b'\x0F\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF')

src/blockchaintree.rs

@@ -1,7 +1,7 @@
 use std::{collections::HashMap, path::Path};
 
 use crate::{
-    block::TransactionBlock,
+    block::{BlockArc, TransactionBlock},
     chain,
     errors::{BCTreeErrorKind, BlockChainTreeError},
     tools,
@@ -303,16 +303,37 @@ impl BlockChainTree {
         Ok(())
     }
 
-    pub async fn new_block(
+    pub async fn add_new_block(
         &self,
-        block: TransactionBlock,
+        block: BlockArc,
         transactions: &[Transaction],
     ) -> Result<(), Report<BlockChainTreeError>> {
-        self.main_chain.add_block(&block).await?;
+        self.main_chain.add_block(block).await?;
 
         self.main_chain.add_transactions(transactions).await
     }
 
+    pub async fn emmit_new_main_block(
+        &self,
+        pow: &[u8],
+        founder: [u8; 33],
+    ) -> Result<[u8; 33], Report<BlockChainTreeError>> {
+        let last_block = self.main_chain.get_last_block().await?.unwrap(); // practically cannot fail
+
+        if !tools::check_pow(
+            &last_block
+                .hash()
+                .change_context(BlockChainTreeError::BlockChainTree(BCTreeErrorKind::DumpDb))
+                .attach_printable("failed to hash block")?,
+            &last_block.get_info().difficulty,
+            pow,
+        ) {
+            return Err(BlockChainTreeError::BlockChainTree(BCTreeErrorKind::WrongPow).into());
+        };
+
+        todo!()
+    }
+
     pub async fn flush(&self) -> Result<(), Report<BlockChainTreeError>> {
         self.main_chain.flush().await?;
         self.summary_db

src/chain.rs

@@ -6,7 +6,7 @@ use primitive_types::U256;
 use sled::Db;
 use tokio::{fs::OpenOptions, io::AsyncWriteExt, sync::RwLock};
 
-use crate::block::DerivativeBlock;
+use crate::block::{BlockArc, DerivativeBlock};
 use crate::dump_headers::Headers;
 use crate::{
     block::{self, BasicInfo, Block, SummarizeBlock},
@@ -126,10 +126,10 @@ impl MainChain {
 
             let merkle_tree = MerkleTree::build_tree(&[tools::hash(&initial_amount)]);
             chain
-                .add_block(&SummarizeBlock {
+                .add_block(Arc::new(SummarizeBlock {
                     default_info: info,
                     merkle_tree_root: *merkle_tree.get_root(),
-                })
+                }))
                 .await
                 .change_context(BlockChainTreeError::Chain(ChainErrorKind::Init))
                 .attach_printable("Failed to insert inception block")?;
@@ -266,10 +266,7 @@ impl MainChain {
     /// Adds block and sets height reference for it
     ///
     /// Checks for blocks validity, adds it directly to the end of the chain
-    pub async fn add_block(
-        &self,
-        block: &(impl Block + Sync),
-    ) -> Result<(), Report<BlockChainTreeError>> {
+    pub async fn add_block(&self, block: BlockArc) -> Result<(), Report<BlockChainTreeError>> {
         let dump = block
             .dump()
             .change_context(BlockChainTreeError::Chain(ChainErrorKind::AddingBlock))?;

src/tools.rs

@@ -183,30 +183,29 @@ pub fn decompress_from_file(filename: String) -> Result<Vec<u8>, ToolsError> {
     Ok(decoded_data)
 }
 
+#[inline]
+pub fn count_leading_zeros(data: &[u8]) -> u32 {
+    let mut to_return = 0u32;
+    for byte in data {
+        let leading_zeros = byte.leading_zeros();
+        to_return += leading_zeros;
+        if leading_zeros < 8 {
+            break;
+        }
+    }
+    to_return
+}
+
 pub fn check_pow(hash: &[u8; 32], difficulty: &[u8; 32], pow: &[u8]) -> bool {
     let mut hasher = Sha256::new();
     hasher.update(hash);
     hasher.update(pow);
-    let result: [u8; 32] = unsafe { hasher.finalize().as_slice().try_into().unwrap_unchecked() };
-    let result: [u64; 4] = unsafe { transmute(result) };
-
-    let difficulty: &[u64; 4] = unsafe { transmute(difficulty) };
+    let result: [u8; 32] = hasher.finalize().into();
 
-    //println!("difficulty: {:?}", difficulty);
-
-    for (r, d) in result.iter().zip(difficulty) {
-        match r.cmp(d) {
-            std::cmp::Ordering::Less => {
-                return true;
-            }
-            std::cmp::Ordering::Equal => {}
-            std::cmp::Ordering::Greater => {
-                return false;
-            }
-        }
+    if count_leading_zeros(difficulty) <= count_leading_zeros(&result) {
+        return true;
     }
-
-    true
+    false
 }
 
 pub fn recalculate_difficulty(prev_timestamp: u64, timestamp: u64, prev_difficulty: &mut Hash) {
@@ -242,8 +241,6 @@ mod tests {
 
     use primitive_types::U256;
 
-    
-
     use super::{dump_u256, load_u256, recalculate_difficulty};
 
     #[test]

tests/chain_test.rs

@@ -1,3 +1,5 @@
+use std::sync::Arc;
+
 use blockchaintree::{
     block, chain, tools,
     transaction::{self, Transactionable},
@@ -32,7 +34,7 @@ async fn init_flush_get_block_by_height_chain_test() {
         vec![[0; 32], [1; 32]],
     );
 
-    main_chain.add_block(&main_block).await.unwrap();
+    main_chain.add_block(Arc::new(main_block)).await.unwrap();
 
     let height = main_chain.get_height().await;
     let block = main_chain.find_by_height(&(height - 1)).await.unwrap();

tests/tools_test.rs

@@ -0,0 +1,4 @@
+use blockchaintree::tools;
+
+#[test]
+fn pow_test() {}