Don't recreate db every run (#131)

Cargo.toml

@@ -16,7 +16,7 @@ integer-cbrt = "0.1.2"
 integer-sqrt = "0.1.5"
 log = "0.4.14"
 memmap2 = "0.5.3"
-redb = "0.0.4"
+redb = { version = "0.0.4", git = "https://github.com/cberner/redb.git" }
 structopt = "0.3.25"
 tempfile = "3.2.0"
 unindent = "0.1.7"

src/index.rs

@@ -29,8 +29,18 @@ impl Index {
         .join(".bitcoin/blocks")
     };
 
+    let result = unsafe { Database::open("index.redb") };
+
+    let database = match result {
+      Ok(database) => database,
+      Err(redb::Error::Io(error)) if error.kind() == io::ErrorKind::NotFound => unsafe {
+        Database::create("index.redb", index_size.unwrap_or(1 << 20))?
+      },
+      Err(error) => return Err(error.into()),
+    };
+
     let index = Self {
-      database: unsafe { Database::open("index.redb", index_size.unwrap_or(1 << 20))? },
+      database,
       blocksdir,
     };
 
@@ -71,7 +81,7 @@ impl Index {
             .get(key.as_slice())?
             .ok_or("Could not find outpoint in index")?;
 
-          for chunk in ordinal_ranges.to_value().chunks_exact(16) {
+          for chunk in ordinal_ranges.chunks_exact(16) {
             let start = u64::from_le_bytes(chunk[0..8].try_into().unwrap());
             let end = u64::from_le_bytes(chunk[8..16].try_into().unwrap());
             input_ordinal_ranges.push_back((start, end));
@@ -260,7 +270,6 @@ impl Index {
       height_to_hash
         .get(&0)?
         .ok_or("Could not find genesis block in index")?
-        .to_value()
         .to_vec(),
       0,
     )];
@@ -300,14 +309,13 @@ impl Index {
     match heights_to_hash.get(&height)? {
       None => Ok(None),
       Some(guard) => {
-        let hash = guard.to_value();
+        let hash = guard;
 
         let hash_to_location: ReadOnlyTable<[u8], u64> = tx.open_table(Self::HASH_TO_LOCATION)?;
 
         let location = hash_to_location
           .get(hash)?
-          .ok_or("Could not find block location in index")?
-          .to_value();
+          .ok_or("Could not find block location in index")?;
 
         let path = self.blockfile_path(location >> 32);
 
@@ -335,7 +343,7 @@ impl Index {
       .ok_or("Could not find outpoint in index")?;
 
     let mut output = Vec::new();
-    for chunk in ordinal_ranges.to_value().chunks_exact(16) {
+    for chunk in ordinal_ranges.chunks_exact(16) {
       let start = u64::from_le_bytes(chunk[0..8].try_into().unwrap());
       let end = u64::from_le_bytes(chunk[8..16].try_into().unwrap());
       output.push((start, end));

src/main.rs

@@ -21,6 +21,7 @@ use {
     collections::VecDeque,
     fmt::{self, Display, Formatter},
     fs::File,
+    io,
     ops::{Add, AddAssign, Deref, Sub},
     path::{Path, PathBuf},
     process,