Change: use the rayon crate for concurrency

3 files changed, 113 insertions, 3 deletions

diff --git a/Cargo.lock b/Cargo.lock
index c1f3d84..11a6e80 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,4 +1,12 @@
 [[package]]
+name = "arrayvec"
+version = "0.4.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "nodrop 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "bitflags"
 version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -40,6 +48,37 @@ dependencies = [
 ]
 
 [[package]]
+name = "crossbeam-deque"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "crossbeam-epoch 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-utils 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "crossbeam-epoch"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "arrayvec 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cfg-if 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "crossbeam-utils 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memoffset 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "nodrop 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)",
+ "scopeguard 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "crossbeam-utils"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "crypto-hash"
 version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -56,6 +95,11 @@ version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "either"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "foreign-types"
 version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -92,6 +136,16 @@ version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "memoffset"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "nodrop"
+version = "0.1.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "num-integer"
 version = "0.1.39"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -105,6 +159,14 @@ version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "num_cpus"
+version = "1.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "libc 0.2.43 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "openssl"
 version = "0.10.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -134,6 +196,27 @@ version = "0.3.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "rayon"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "crossbeam-deque 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "either 1.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rayon-core 1.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rayon-core"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "crossbeam-deque 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.43 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num_cpus 1.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "redox_syscall"
 version = "0.1.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -147,6 +230,11 @@ dependencies = [
 ]
 
 [[package]]
+name = "scopeguard"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "serde"
 version = "1.0.79"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -169,6 +257,7 @@ dependencies = [
  "chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "crypto-hash 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rayon 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.79 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_yaml 0.8.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "users 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -249,27 +338,38 @@ dependencies = [
 ]
 
 [metadata]
+"checksum arrayvec 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)" = "a1e964f9e24d588183fcb43503abda40d288c8657dfc27311516ce2f05675aef"
 "checksum bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "228047a76f468627ca71776ecdebd732a3423081fcf5125585bcd7c49886ce12"
 "checksum cc 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)" = "f159dfd43363c4d08055a07703eb7a3406b0dac4d0584d96965a3262db3c9d16"
 "checksum cfg-if 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "0c4e7bb64a8ebb0d856483e1e682ea3422f883c5f5615a90d51a2c82fe87fdd3"
 "checksum chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "45912881121cb26fad7c38c17ba7daa18764771836b34fab7d3fbd93ed633878"
 "checksum commoncrypto 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d056a8586ba25a1e4d61cb090900e495952c7886786fc55f909ab2f819b69007"
 "checksum commoncrypto-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1fed34f46747aa73dfaa578069fd8279d2818ade2b55f38f22a9401c7f4083e2"
+"checksum crossbeam-deque 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f739f8c5363aca78cfb059edf753d8f0d36908c348f3d8d1503f03d8b75d9cf3"
+"checksum crossbeam-epoch 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "927121f5407de9956180ff5e936fe3cf4324279280001cd56b669d28ee7e9150"
+"checksum crossbeam-utils 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "2760899e32a1d58d5abb31129f8fae5de75220bc2176e77ff7c627ae45c918d9"
 "checksum crypto-hash 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "09de9ee0fc255ace04c7fa0763c9395a945c37c8292bb554f8d48361d1dcf1b4"
 "checksum dtoa 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "6d301140eb411af13d3115f9a562c85cc6b541ade9dfa314132244aaee7489dd"
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 "checksum foreign-types 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f6f339eb8adc052cd2ca78910fda869aefa38d22d5cb648e6485e4d3fc06f3b1"
 "checksum foreign-types-shared 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "00b0228411908ca8685dba7fc2cdd70ec9990a6e753e89b6ac91a84c40fbaf4b"
 "checksum hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "805026a5d0141ffc30abb3be3173848ad46a1b1664fe632428479619a3644d77"
 "checksum lazy_static 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ca488b89a5657b0a2ecd45b95609b3e848cf1755da332a0da46e2b2b1cb371a7"
 "checksum libc 0.2.43 (registry+https://github.com/rust-lang/crates.io-index)" = "76e3a3ef172f1a0b9a9ff0dd1491ae5e6c948b94479a3021819ba7d860c8645d"
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+"checksum memoffset 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0f9dc261e2b62d7a622bf416ea3c5245cdd5d9a7fcc428c0d06804dfce1775b3"
+"checksum nodrop 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)" = "9a2228dca57108069a5262f2ed8bd2e82496d2e074a06d1ccc7ce1687b6ae0a2"
 "checksum num-integer 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)" = "e83d528d2677f0518c570baf2b7abdcf0cd2d248860b68507bdcb3e91d4c0cea"
 "checksum num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "0b3a5d7cc97d6d30d8b9bc8fa19bf45349ffe46241e8816f50f62f6d6aaabee1"
+"checksum num_cpus 1.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c51a3322e4bca9d212ad9a158a02abc6934d005490c054a2778df73a70aa0a30"
 "checksum openssl 0.10.12 (registry+https://github.com/rust-lang/crates.io-index)" = "5e2e79eede055813a3ac52fb3915caf8e1c9da2dec1587871aec9f6f7b48508d"
 "checksum openssl-sys 0.9.36 (registry+https://github.com/rust-lang/crates.io-index)" = "409d77eeb492a1aebd6eb322b2ee72ff7c7496b4434d98b3bf8be038755de65e"
 "checksum pkg-config 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)" = "676e8eb2b1b4c9043511a9b7bea0915320d7e502b0a079fb03f9635a5252b18c"
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+"checksum rayon-core 1.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b055d1e92aba6877574d8fe604a63c8b5df60f60e5982bf7ccbb1338ea527356"
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diff --git a/Cargo.toml b/Cargo.toml
index dd1dac4..ba80db9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,3 +11,4 @@ hex = "0.3.2"
 walkdir = "2.2.5"
 serde = "1.0"
 serde_yaml = "0.8"
+rayon = "1.0.2"
diff --git a/src/main.rs b/src/main.rs
index e797b58..d49266b 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,21 +2,30 @@ extern crate chrono;
 extern crate crypto_hash;
 extern crate serde_yaml;
 extern crate walkdir;
+extern crate rayon;
 
 use std::env;
 use std::io;
 use std::collections::BTreeMap;
 use walkdir::{WalkDir, DirEntry};
+use rayon::prelude::*;
 
 mod format;
 
 
+type Map = BTreeMap<&'static str, String>;
+
+
 fn main() -> io::Result<()> {
     for dirname in env::args().skip(1) {
-        let maps = WalkDir::new(&dirname)
+        let maps: Vec<DirEntry> = WalkDir::new(&dirname)
             .into_iter()
             .filter_map(|e| e.ok())
-            .map(|e| mkmap(e));
+            .collect();
+        let maps: Vec<Map> = maps
+            .into_par_iter()
+            .map(mkmap)
+            .collect();
         for map in maps {
             println!("{}", serde_yaml::to_string(&map).unwrap());
         }
@@ -25,7 +34,7 @@ fn main() -> io::Result<()> {
 }
 
 
-fn mkmap(e: DirEntry) -> BTreeMap<&'static str, String> {
+fn mkmap(e: DirEntry) -> Map {
     let fields = vec![
         ("Name", format::name(&e)),
         ("Mtime", format::mtime(&e)),