| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `common/rusty_leveldb_sgx/src/block.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>block.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../normalize.css"><link rel="stylesheet" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../ayu.css" disabled><link rel="stylesheet" href="../../dark.css" disabled><link rel="stylesheet" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="../../source-script.js"></script><script defer src="../../source-files.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../rusty_leveldb/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../rusty_leveldb/index.html"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="kw">use </span>std::cmp::Ordering; |
| <span class="kw">use </span>std::rc::Rc; |
| |
| <span class="kw">use </span><span class="kw">crate</span>::options::Options; |
| <span class="kw">use </span><span class="kw">crate</span>::types::LdbIterator; |
| |
| <span class="kw">use </span>integer_encoding::FixedInt; |
| <span class="kw">use </span>integer_encoding::VarInt; |
| |
| <span class="kw">pub type </span>BlockContents = Vec<u8>; |
| |
| <span class="doccomment">/// A Block is an immutable ordered set of key/value entries. |
| /// |
| /// The structure internally looks like follows: |
| /// |
| /// A block is a list of ENTRIES followed by a list of RESTARTS, terminated by a fixed u32 |
| /// N_RESTARTS. |
| /// |
| /// An ENTRY consists of three varints, SHARED, NON_SHARED, VALSIZE, a KEY and a VALUE. |
| /// |
| /// SHARED denotes how many bytes the entry's key shares with the previous one. |
| /// |
| /// NON_SHARED is the size of the key minus SHARED. |
| /// |
| /// VALSIZE is the size of the value. |
| /// |
| /// KEY and VALUE are byte strings; the length of KEY is NON_SHARED. |
| /// |
| /// A RESTART is a fixed u32 pointing to the beginning of an ENTRY. |
| /// |
| /// N_RESTARTS contains the number of restarts. |
| </span><span class="attribute">#[derive(Clone)] |
| </span><span class="kw">pub struct </span>Block { |
| block: Rc<BlockContents>, |
| opt: Options, |
| } |
| |
| <span class="kw">impl </span>Block { |
| <span class="doccomment">/// Return an iterator over this block. |
| /// Note that the iterator isn't bound to the block's lifetime; the iterator uses the same |
| /// refcounted block contents as this block, meaning that if the iterator isn't released, |
| /// the memory occupied by the block isn't, either) |
| </span><span class="kw">pub fn </span>iter(<span class="kw-2">&</span><span class="self">self</span>) -> BlockIter { |
| <span class="kw">let </span>restarts = u32::decode_fixed(<span class="kw-2">&</span><span class="self">self</span>.block[<span class="self">self</span>.block.len() - <span class="number">4</span>..]); |
| <span class="kw">let </span>restart_offset = <span class="self">self</span>.block.len() - <span class="number">4 </span>- <span class="number">4 </span>* restarts <span class="kw">as </span>usize; |
| |
| BlockIter { |
| block: <span class="self">self</span>.block.clone(), |
| opt: <span class="self">self</span>.opt.clone(), |
| |
| offset: <span class="number">0</span>, |
| restarts_off: restart_offset, |
| current_entry_offset: <span class="number">0</span>, |
| current_restart_ix: <span class="number">0</span>, |
| |
| key: Vec::new(), |
| val_offset: <span class="number">0</span>, |
| } |
| } |
| |
| <span class="kw">pub fn </span>contents(<span class="kw-2">&</span><span class="self">self</span>) -> Rc<BlockContents> { |
| <span class="self">self</span>.block.clone() |
| } |
| |
| <span class="kw">pub fn </span>new(opt: Options, contents: BlockContents) -> Block { |
| <span class="macro">assert!</span>(contents.len() > <span class="number">4</span>); |
| Block { |
| block: Rc::new(contents), |
| opt, |
| } |
| } |
| } |
| |
| <span class="doccomment">/// BlockIter is an iterator over the entries in a block. It doesn't depend on the Block's |
| /// lifetime, as it uses a refcounted block underneath. |
| </span><span class="kw">pub struct </span>BlockIter { |
| <span class="doccomment">/// The underlying block contents. |
| /// TODO: Maybe (probably...) this needs an Arc. |
| </span>block: Rc<BlockContents>, |
| opt: Options, |
| <span class="doccomment">/// offset of restarts area within the block. |
| </span>restarts_off: usize, |
| |
| <span class="doccomment">/// start of next entry to be parsed. |
| </span>offset: usize, |
| <span class="doccomment">/// offset of the current entry. |
| </span>current_entry_offset: usize, |
| <span class="doccomment">/// index of the most recent restart. |
| </span>current_restart_ix: usize, |
| |
| <span class="doccomment">/// We assemble the key from two parts usually, so we keep the current full key here. |
| </span>key: Vec<u8>, |
| <span class="doccomment">/// Offset of the current value within the block. |
| </span>val_offset: usize, |
| } |
| |
| <span class="kw">impl </span>BlockIter { |
| <span class="doccomment">/// Return the number of restarts in this block. |
| </span><span class="kw">fn </span>number_restarts(<span class="kw-2">&</span><span class="self">self</span>) -> usize { |
| u32::decode_fixed(<span class="kw-2">&</span><span class="self">self</span>.block[<span class="self">self</span>.block.len() - <span class="number">4</span>..]) <span class="kw">as </span>usize |
| } |
| |
| <span class="doccomment">/// Seek to restart point `ix`. After the seek, current() will return the entry at that restart |
| /// point. |
| </span><span class="kw">fn </span>seek_to_restart_point(<span class="kw-2">&mut </span><span class="self">self</span>, ix: usize) { |
| <span class="kw">let </span>off = <span class="self">self</span>.get_restart_point(ix); |
| |
| <span class="self">self</span>.offset = off; |
| <span class="self">self</span>.current_entry_offset = off; |
| <span class="self">self</span>.current_restart_ix = ix; |
| <span class="comment">// advances self.offset to point to the next entry |
| </span><span class="kw">let </span>(shared, non_shared, <span class="kw">_</span>, head_len) = <span class="self">self</span>.parse_entry_and_advance(); |
| |
| <span class="macro">assert_eq!</span>(shared, <span class="number">0</span>); |
| <span class="self">self</span>.assemble_key(off + head_len, shared, non_shared); |
| <span class="macro">assert!</span>(<span class="self">self</span>.valid()); |
| } |
| |
| <span class="doccomment">/// Return the offset that restart `ix` points to. |
| </span><span class="kw">fn </span>get_restart_point(<span class="kw-2">&</span><span class="self">self</span>, ix: usize) -> usize { |
| <span class="kw">let </span>restart = <span class="self">self</span>.restarts_off + <span class="number">4 </span>* ix; |
| u32::decode_fixed(<span class="kw-2">&</span><span class="self">self</span>.block[restart..restart + <span class="number">4</span>]) <span class="kw">as </span>usize |
| } |
| |
| <span class="doccomment">/// The layout of an entry is |
| /// [SHARED varint, NON_SHARED varint, VALSIZE varint, KEY (NON_SHARED bytes), |
| /// VALUE (VALSIZE bytes)]. |
| /// |
| /// Returns SHARED, NON_SHARED, VALSIZE and [length of length spec] from the current position, |
| /// where 'length spec' is the length of the three values in the entry header, as described |
| /// above. |
| /// Advances self.offset to the beginning of the next entry. |
| </span><span class="kw">fn </span>parse_entry_and_advance(<span class="kw-2">&mut </span><span class="self">self</span>) -> (usize, usize, usize, usize) { |
| <span class="kw">let </span><span class="kw-2">mut </span>i = <span class="number">0</span>; |
| <span class="kw">let </span>(shared, sharedlen) = usize::decode_var(<span class="kw-2">&</span><span class="self">self</span>.block[<span class="self">self</span>.offset..]); |
| i += sharedlen; |
| |
| <span class="kw">let </span>(non_shared, non_sharedlen) = usize::decode_var(<span class="kw-2">&</span><span class="self">self</span>.block[<span class="self">self</span>.offset + i..]); |
| i += non_sharedlen; |
| |
| <span class="kw">let </span>(valsize, valsizelen) = usize::decode_var(<span class="kw-2">&</span><span class="self">self</span>.block[<span class="self">self</span>.offset + i..]); |
| i += valsizelen; |
| |
| <span class="self">self</span>.val_offset = <span class="self">self</span>.offset + i + non_shared; |
| <span class="self">self</span>.offset = <span class="self">self</span>.val_offset + valsize; |
| |
| (shared, non_shared, valsize, i) |
| } |
| |
| <span class="doccomment">/// Assemble the current key from shared and non-shared parts (an entry usually contains only |
| /// the part of the key that is different from the previous key). |
| /// |
| /// `off` is the offset of the key string within the whole block (self.current_entry_offset |
| /// + entry header length); `shared` and `non_shared` are the lengths of the shared |
| /// respectively non-shared parts of the key. |
| /// Only self.key is mutated. |
| </span><span class="kw">fn </span>assemble_key(<span class="kw-2">&mut </span><span class="self">self</span>, off: usize, shared: usize, non_shared: usize) { |
| <span class="self">self</span>.key.truncate(shared); |
| <span class="self">self</span>.key |
| .extend_from_slice(<span class="kw-2">&</span><span class="self">self</span>.block[off..off + non_shared]); |
| } |
| |
| <span class="kw">pub fn </span>seek_to_last(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="kw">if </span><span class="self">self</span>.number_restarts() > <span class="number">0 </span>{ |
| <span class="kw">let </span>num_restarts = <span class="self">self</span>.number_restarts(); |
| <span class="self">self</span>.seek_to_restart_point(num_restarts - <span class="number">1</span>); |
| } <span class="kw">else </span>{ |
| <span class="self">self</span>.reset(); |
| } |
| |
| <span class="comment">// Stop at last entry, before the iterator becomes invalid. |
| // |
| // We're checking the position before calling advance; if a restart point points to the |
| // last entry, calling advance() will directly reset the iterator. |
| </span><span class="kw">while </span><span class="self">self</span>.offset < <span class="self">self</span>.restarts_off { |
| <span class="self">self</span>.advance(); |
| } |
| <span class="macro">assert!</span>(<span class="self">self</span>.valid()); |
| } |
| } |
| |
| <span class="kw">impl </span>LdbIterator <span class="kw">for </span>BlockIter { |
| <span class="kw">fn </span>advance(<span class="kw-2">&mut </span><span class="self">self</span>) -> bool { |
| <span class="kw">if </span><span class="self">self</span>.offset >= <span class="self">self</span>.restarts_off { |
| <span class="self">self</span>.reset(); |
| <span class="kw">return </span><span class="bool-val">false</span>; |
| } <span class="kw">else </span>{ |
| <span class="self">self</span>.current_entry_offset = <span class="self">self</span>.offset; |
| } |
| |
| <span class="kw">let </span>current_off = <span class="self">self</span>.current_entry_offset; |
| |
| <span class="kw">let </span>(shared, non_shared, _valsize, entry_head_len) = <span class="self">self</span>.parse_entry_and_advance(); |
| <span class="self">self</span>.assemble_key(current_off + entry_head_len, shared, non_shared); |
| |
| <span class="comment">// Adjust current_restart_ix |
| </span><span class="kw">let </span>num_restarts = <span class="self">self</span>.number_restarts(); |
| <span class="kw">while </span><span class="self">self</span>.current_restart_ix + <span class="number">1 </span>< num_restarts |
| && <span class="self">self</span>.get_restart_point(<span class="self">self</span>.current_restart_ix + <span class="number">1</span>) < <span class="self">self</span>.current_entry_offset |
| { |
| <span class="self">self</span>.current_restart_ix += <span class="number">1</span>; |
| } |
| <span class="bool-val">true |
| </span>} |
| |
| <span class="kw">fn </span>reset(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="self">self</span>.offset = <span class="number">0</span>; |
| <span class="self">self</span>.val_offset = <span class="number">0</span>; |
| <span class="self">self</span>.current_restart_ix = <span class="number">0</span>; |
| <span class="self">self</span>.key.clear(); |
| } |
| |
| <span class="kw">fn </span>prev(<span class="kw-2">&mut </span><span class="self">self</span>) -> bool { |
| <span class="comment">// as in the original implementation -- seek to last restart point, then look for key |
| </span><span class="kw">let </span>orig_offset = <span class="self">self</span>.current_entry_offset; |
| |
| <span class="comment">// At the beginning, can't go further back |
| </span><span class="kw">if </span>orig_offset == <span class="number">0 </span>{ |
| <span class="self">self</span>.reset(); |
| <span class="kw">return </span><span class="bool-val">false</span>; |
| } |
| |
| <span class="kw">while </span><span class="self">self</span>.get_restart_point(<span class="self">self</span>.current_restart_ix) >= orig_offset { |
| <span class="comment">// todo: double check this |
| </span><span class="kw">if </span><span class="self">self</span>.current_restart_ix == <span class="number">0 </span>{ |
| <span class="self">self</span>.offset = <span class="self">self</span>.restarts_off; |
| <span class="self">self</span>.current_restart_ix = <span class="self">self</span>.number_restarts(); |
| <span class="kw">break</span>; |
| } |
| <span class="self">self</span>.current_restart_ix -= <span class="number">1</span>; |
| } |
| |
| <span class="self">self</span>.offset = <span class="self">self</span>.get_restart_point(<span class="self">self</span>.current_restart_ix); |
| <span class="macro">assert!</span>(<span class="self">self</span>.offset < orig_offset); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>result; |
| |
| <span class="comment">// Stop if the next entry would be the original one (self.offset always points to the start |
| // of the next entry) |
| </span><span class="kw">loop </span>{ |
| result = <span class="self">self</span>.advance(); |
| <span class="kw">if </span><span class="self">self</span>.offset >= orig_offset { |
| <span class="kw">break</span>; |
| } |
| } |
| result |
| } |
| |
| <span class="kw">fn </span>seek(<span class="kw-2">&mut </span><span class="self">self</span>, to: <span class="kw-2">&</span>[u8]) { |
| <span class="self">self</span>.reset(); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>left = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>right = <span class="kw">if </span><span class="self">self</span>.number_restarts() == <span class="number">0 </span>{ |
| <span class="number">0 |
| </span>} <span class="kw">else </span>{ |
| <span class="self">self</span>.number_restarts() - <span class="number">1 |
| </span>}; |
| |
| <span class="comment">// Do a binary search over the restart points. |
| </span><span class="kw">while </span>left < right { |
| <span class="kw">let </span>middle = (left + right + <span class="number">1</span>) / <span class="number">2</span>; |
| <span class="self">self</span>.seek_to_restart_point(middle); |
| |
| <span class="kw">let </span>c = <span class="self">self</span>.opt.cmp.cmp(<span class="kw-2">&</span><span class="self">self</span>.key, to); |
| |
| <span class="kw">if </span>c == Ordering::Less { |
| left = middle; |
| } <span class="kw">else </span>{ |
| right = middle - <span class="number">1</span>; |
| } |
| } |
| |
| <span class="macro">assert_eq!</span>(left, right); |
| <span class="self">self</span>.current_restart_ix = left; |
| <span class="self">self</span>.offset = <span class="self">self</span>.get_restart_point(left); |
| |
| <span class="comment">// Linear search from here on |
| </span><span class="kw">while let </span><span class="prelude-val">Some</span>((k, <span class="kw">_</span>)) = <span class="self">self</span>.next() { |
| <span class="kw">if </span><span class="self">self</span>.opt.cmp.cmp(k.as_slice(), to) >= Ordering::Equal { |
| <span class="kw">return</span>; |
| } |
| } |
| } |
| |
| <span class="kw">fn </span>valid(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| !<span class="self">self</span>.key.is_empty() && <span class="self">self</span>.val_offset > <span class="number">0 </span>&& <span class="self">self</span>.val_offset <= <span class="self">self</span>.restarts_off |
| } |
| |
| <span class="kw">fn </span>current(<span class="kw-2">&</span><span class="self">self</span>, key: <span class="kw-2">&mut </span>Vec<u8>, val: <span class="kw-2">&mut </span>Vec<u8>) -> bool { |
| <span class="kw">if </span><span class="self">self</span>.valid() { |
| key.clear(); |
| val.clear(); |
| key.extend_from_slice(<span class="kw-2">&</span><span class="self">self</span>.key); |
| val.extend_from_slice(<span class="kw-2">&</span><span class="self">self</span>.block[<span class="self">self</span>.val_offset..<span class="self">self</span>.offset]); |
| <span class="bool-val">true |
| </span>} <span class="kw">else </span>{ |
| <span class="bool-val">false |
| </span>} |
| } |
| } |
| |
| <span class="attribute">#[cfg(feature = <span class="string">"enclave_unit_test"</span>)] |
| </span><span class="kw">pub mod </span>tests { |
| <span class="kw">use super</span>::<span class="kw-2">*</span>; |
| <span class="kw">use </span><span class="kw">crate</span>::block_builder::BlockBuilder; |
| <span class="kw">use </span><span class="kw">crate</span>::options; |
| <span class="kw">use </span><span class="kw">crate</span>::test_util::{test_iterator_properties, LdbIteratorIter}; |
| <span class="kw">use </span><span class="kw">crate</span>::types::{current_key_val, LdbIterator}; |
| <span class="kw">use </span>teaclave_test_utils::<span class="kw-2">*</span>; |
| |
| <span class="kw">pub fn </span>run_tests() -> bool { |
| <span class="macro">run_tests!</span>( |
| test_block_iterator_properties, |
| test_block_empty, |
| test_block_build_iterate, |
| test_block_iterate_reverse, |
| test_block_seek, |
| test_block_seek_to_last, |
| ) |
| } |
| |
| <span class="kw">fn </span>get_data() -> Vec<(<span class="kw-2">&</span><span class="lifetime">'static </span>[u8], <span class="kw-2">&</span><span class="lifetime">'static </span>[u8])> { |
| <span class="macro">vec!</span>[ |
| (<span class="string">"key1"</span>.as_bytes(), <span class="string">"value1"</span>.as_bytes()), |
| ( |
| <span class="string">"loooooooooooooooooooooooooooooooooongerkey1"</span>.as_bytes(), |
| <span class="string">"shrtvl1"</span>.as_bytes(), |
| ), |
| (<span class="string">"medium length key 1"</span>.as_bytes(), <span class="string">"some value 2"</span>.as_bytes()), |
| (<span class="string">"prefix_key1"</span>.as_bytes(), <span class="string">"value"</span>.as_bytes()), |
| (<span class="string">"prefix_key2"</span>.as_bytes(), <span class="string">"value"</span>.as_bytes()), |
| (<span class="string">"prefix_key3"</span>.as_bytes(), <span class="string">"value"</span>.as_bytes()), |
| ] |
| } |
| |
| <span class="kw">fn </span>test_block_iterator_properties() { |
| <span class="kw">let </span>o = options::for_test(); |
| <span class="kw">let </span><span class="kw-2">mut </span>builder = BlockBuilder::new(o.clone()); |
| <span class="kw">let </span><span class="kw-2">mut </span>data = get_data(); |
| data.truncate(<span class="number">4</span>); |
| <span class="kw">for </span><span class="kw-2">&</span>(k, v) <span class="kw">in </span>data.iter() { |
| builder.add(k, v); |
| } |
| <span class="kw">let </span>block_contents = builder.finish(); |
| |
| <span class="kw">let </span>block = Block::new(o.clone(), block_contents).iter(); |
| test_iterator_properties(block); |
| } |
| |
| <span class="kw">fn </span>test_block_empty() { |
| <span class="kw">let </span><span class="kw-2">mut </span>o = options::for_test(); |
| o.block_restart_interval = <span class="number">16</span>; |
| <span class="kw">let </span>builder = BlockBuilder::new(o); |
| |
| <span class="kw">let </span>blockc = builder.finish(); |
| <span class="macro">assert_eq!</span>(blockc.len(), <span class="number">8</span>); |
| <span class="macro">assert_eq!</span>(blockc, <span class="macro">vec!</span>[<span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>]); |
| |
| <span class="kw">let </span>block = Block::new(options::for_test(), blockc); |
| |
| <span class="kw">for _ in </span>LdbIteratorIter::wrap(<span class="kw-2">&mut </span>block.iter()) { |
| <span class="macro">panic!</span>(<span class="string">"expected 0 iterations"</span>); |
| } |
| } |
| |
| <span class="kw">fn </span>test_block_build_iterate() { |
| <span class="kw">let </span>data = get_data(); |
| <span class="kw">let </span><span class="kw-2">mut </span>builder = BlockBuilder::new(options::for_test()); |
| |
| <span class="kw">for </span><span class="kw-2">&</span>(k, v) <span class="kw">in </span>data.iter() { |
| builder.add(k, v); |
| } |
| |
| <span class="kw">let </span>block_contents = builder.finish(); |
| <span class="kw">let </span><span class="kw-2">mut </span>block = Block::new(options::for_test(), block_contents).iter(); |
| <span class="kw">let </span><span class="kw-2">mut </span>i = <span class="number">0</span>; |
| |
| <span class="macro">assert!</span>(!block.valid()); |
| |
| <span class="kw">for </span>(k, v) <span class="kw">in </span>LdbIteratorIter::wrap(<span class="kw-2">&mut </span>block) { |
| <span class="macro">assert_eq!</span>(<span class="kw-2">&</span>k[..], data[i].<span class="number">0</span>); |
| <span class="macro">assert_eq!</span>(v, data[i].<span class="number">1</span>); |
| i += <span class="number">1</span>; |
| } |
| <span class="macro">assert_eq!</span>(i, data.len()); |
| } |
| |
| <span class="kw">fn </span>test_block_iterate_reverse() { |
| <span class="kw">let </span><span class="kw-2">mut </span>o = options::for_test(); |
| o.block_restart_interval = <span class="number">3</span>; |
| <span class="kw">let </span>data = get_data(); |
| <span class="kw">let </span><span class="kw-2">mut </span>builder = BlockBuilder::new(o.clone()); |
| |
| <span class="kw">for </span><span class="kw-2">&</span>(k, v) <span class="kw">in </span>data.iter() { |
| builder.add(k, v); |
| } |
| |
| <span class="kw">let </span>block_contents = builder.finish(); |
| <span class="kw">let </span><span class="kw-2">mut </span>block = Block::new(o.clone(), block_contents).iter(); |
| |
| <span class="macro">assert!</span>(!block.valid()); |
| <span class="macro">assert_eq!</span>( |
| block.next(), |
| <span class="prelude-val">Some</span>((<span class="string">"key1"</span>.as_bytes().to_vec(), <span class="string">"value1"</span>.as_bytes().to_vec())) |
| ); |
| <span class="macro">assert!</span>(block.valid()); |
| block.next(); |
| <span class="macro">assert!</span>(block.valid()); |
| block.prev(); |
| <span class="macro">assert!</span>(block.valid()); |
| <span class="macro">assert_eq!</span>( |
| current_key_val(<span class="kw-2">&</span>block), |
| <span class="prelude-val">Some</span>((<span class="string">"key1"</span>.as_bytes().to_vec(), <span class="string">"value1"</span>.as_bytes().to_vec())) |
| ); |
| block.prev(); |
| <span class="macro">assert!</span>(!block.valid()); |
| |
| <span class="comment">// Verify that prev() from the last entry goes to the prev-to-last entry |
| // (essentially, that next() returning None doesn't advance anything) |
| </span><span class="kw">while let </span><span class="prelude-val">Some</span>(<span class="kw">_</span>) = block.next() {} |
| |
| block.prev(); |
| <span class="macro">assert!</span>(block.valid()); |
| <span class="macro">assert_eq!</span>( |
| current_key_val(<span class="kw-2">&</span>block), |
| <span class="prelude-val">Some</span>(( |
| <span class="string">"prefix_key2"</span>.as_bytes().to_vec(), |
| <span class="string">"value"</span>.as_bytes().to_vec() |
| )) |
| ); |
| } |
| |
| <span class="kw">fn </span>test_block_seek() { |
| <span class="kw">let </span><span class="kw-2">mut </span>o = options::for_test(); |
| o.block_restart_interval = <span class="number">3</span>; |
| |
| <span class="kw">let </span>data = get_data(); |
| <span class="kw">let </span><span class="kw-2">mut </span>builder = BlockBuilder::new(o.clone()); |
| |
| <span class="kw">for </span><span class="kw-2">&</span>(k, v) <span class="kw">in </span>data.iter() { |
| builder.add(k, v); |
| } |
| |
| <span class="kw">let </span>block_contents = builder.finish(); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>block = Block::new(o.clone(), block_contents).iter(); |
| |
| block.seek(<span class="kw-2">&</span><span class="string">"prefix_key2"</span>.as_bytes()); |
| <span class="macro">assert!</span>(block.valid()); |
| <span class="macro">assert_eq!</span>( |
| current_key_val(<span class="kw-2">&</span>block), |
| <span class="prelude-val">Some</span>(( |
| <span class="string">"prefix_key2"</span>.as_bytes().to_vec(), |
| <span class="string">"value"</span>.as_bytes().to_vec() |
| )) |
| ); |
| |
| block.seek(<span class="kw-2">&</span><span class="string">"prefix_key0"</span>.as_bytes()); |
| <span class="macro">assert!</span>(block.valid()); |
| <span class="macro">assert_eq!</span>( |
| current_key_val(<span class="kw-2">&</span>block), |
| <span class="prelude-val">Some</span>(( |
| <span class="string">"prefix_key1"</span>.as_bytes().to_vec(), |
| <span class="string">"value"</span>.as_bytes().to_vec() |
| )) |
| ); |
| |
| block.seek(<span class="kw-2">&</span><span class="string">"key1"</span>.as_bytes()); |
| <span class="macro">assert!</span>(block.valid()); |
| <span class="macro">assert_eq!</span>( |
| current_key_val(<span class="kw-2">&</span>block), |
| <span class="prelude-val">Some</span>((<span class="string">"key1"</span>.as_bytes().to_vec(), <span class="string">"value1"</span>.as_bytes().to_vec())) |
| ); |
| |
| block.seek(<span class="kw-2">&</span><span class="string">"prefix_key3"</span>.as_bytes()); |
| <span class="macro">assert!</span>(block.valid()); |
| <span class="macro">assert_eq!</span>( |
| current_key_val(<span class="kw-2">&</span>block), |
| <span class="prelude-val">Some</span>(( |
| <span class="string">"prefix_key3"</span>.as_bytes().to_vec(), |
| <span class="string">"value"</span>.as_bytes().to_vec() |
| )) |
| ); |
| |
| block.seek(<span class="kw-2">&</span><span class="string">"prefix_key8"</span>.as_bytes()); |
| <span class="macro">assert!</span>(!block.valid()); |
| <span class="macro">assert_eq!</span>(current_key_val(<span class="kw-2">&</span>block), <span class="prelude-val">None</span>); |
| } |
| |
| <span class="kw">fn </span>test_block_seek_to_last() { |
| <span class="kw">let </span><span class="kw-2">mut </span>o = options::for_test(); |
| |
| <span class="comment">// Test with different number of restarts |
| </span><span class="kw">for </span>block_restart_interval <span class="kw">in </span><span class="macro">vec!</span>[<span class="number">2</span>, <span class="number">6</span>, <span class="number">10</span>] { |
| o.block_restart_interval = block_restart_interval; |
| |
| <span class="kw">let </span>data = get_data(); |
| <span class="kw">let </span><span class="kw-2">mut </span>builder = BlockBuilder::new(o.clone()); |
| |
| <span class="kw">for </span><span class="kw-2">&</span>(k, v) <span class="kw">in </span>data.iter() { |
| builder.add(k, v); |
| } |
| |
| <span class="kw">let </span>block_contents = builder.finish(); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>block = Block::new(o.clone(), block_contents).iter(); |
| |
| block.seek_to_last(); |
| <span class="macro">assert!</span>(block.valid()); |
| <span class="macro">assert_eq!</span>( |
| current_key_val(<span class="kw-2">&</span>block), |
| <span class="prelude-val">Some</span>(( |
| <span class="string">"prefix_key3"</span>.as_bytes().to_vec(), |
| <span class="string">"value"</span>.as_bytes().to_vec() |
| )) |
| ); |
| } |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="rusty_leveldb" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
