Merge branch 'master' into rm-unused-opts

Cargo.lock

@@ -181,7 +181,7 @@ dependencies = [
 
 [[package]]
 name = "image"
-version = "0.23.2"
+version = "0.23.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bytemuck 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -295,7 +295,7 @@ dependencies = [
 
 [[package]]
 name = "num_cpus"
-version = "1.12.0"
+version = "1.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -311,12 +311,11 @@ dependencies = [
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "cloudflare-zlib 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "crc 1.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "image 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "image 0.23.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "indexmap 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "itertools 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "libdeflater 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "miniz_oxide 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "num_cpus 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rayon 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rgb 0.8.16 (registry+https://github.com/rust-lang/crates.io-index)",
  "wild 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -353,7 +352,7 @@ dependencies = [
  "crossbeam-queue 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "num_cpus 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num_cpus 1.13.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -478,7 +477,7 @@ dependencies = [
 "checksum either 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "bb1f6b1ce1c140482ea30ddd3335fc0024ac7ee112895426e0a629a6c20adfe3"
 "checksum glob 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9b919933a397b79c37e33b77bb2aa3dc8eb6e165ad809e58ff75bc7db2e34574"
 "checksum hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "1010591b26bbfe835e9faeabeb11866061cc7dcebffd56ad7d0942d0e61aefd8"
-"checksum image 0.23.2 (registry+https://github.com/rust-lang/crates.io-index)" = "9062b90712d25bc6bb165d110aa59c6b47c849246e341e7b86a98daff9d49f60"
+"checksum image 0.23.3 (registry+https://github.com/rust-lang/crates.io-index)" = "bfc5483f8d5afd3653b38a196c52294dcb239c3e1a5bade1990353ea13bcf387"
 "checksum indexmap 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "076f042c5b7b98f31d205f1249267e12a6518c1481e9dae9764af19b707d2292"
 "checksum inflate 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)" = "1cdb29978cc5797bd8dcc8e5bf7de604891df2a8dc576973d71a281e916db2ff"
 "checksum itertools 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "284f18f85651fe11e8a991b2adb42cb078325c996ed026d994719efcfca1d54b"
@@ -492,7 +491,7 @@ dependencies = [
 "checksum num-iter 0.1.40 (registry+https://github.com/rust-lang/crates.io-index)" = "dfb0800a0291891dd9f4fe7bd9c19384f98f7fbe0cd0f39a2c6b88b9868bbc00"
 "checksum num-rational 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "da4dc79f9e6c81bef96148c8f6b8e72ad4541caa4a24373e900a36da07de03a3"
 "checksum num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "c62be47e61d1842b9170f0fdeec8eba98e60e90e5446449a0545e5152acd7096"
-"checksum num_cpus 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)" = "46203554f085ff89c235cd12f7075f3233af9b11ed7c9e16dfe2560d03313ce6"
+"checksum num_cpus 1.13.0 (registry+https://github.com/rust-lang/crates.io-index)" = "05499f3756671c15885fee9034446956fff3f243d6077b91e5767df161f766b3"
 "checksum png 0.16.1 (registry+https://github.com/rust-lang/crates.io-index)" = "46060468187c21c00ffa2a920690b29997d7fd543f5a4d400461e4a7d4fccde8"
 "checksum rayon 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "db6ce3297f9c85e16621bb8cca38a06779ffc31bb8184e1be4bed2be4678a098"
 "checksum rayon-core 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "08a89b46efaf957e52b18062fb2f4660f8b8a4dde1807ca002690868ef2c85a9"

Cargo.toml

@@ -32,7 +32,6 @@ bit-vec = "^0.6.0"
 byteorder = "^1.0.0"
 crc = "^1.2.0"
 itertools = "^0.9.0"
-num_cpus = "^1.0.0"
 zopfli = "^0.4.0"
 miniz_oxide = "0.3"
 rgb = "0.8.11"

src/evaluate.rs

@@ -12,13 +12,15 @@ use crate::png::STD_WINDOW;
 #[cfg(not(feature = "parallel"))]
 use crate::rayon;
 use crate::Deadline;
-#[cfg(feature = "parallel")]
-use rayon;
 use rayon::prelude::*;
+#[cfg(not(feature = "parallel"))]
+use std::cell::RefCell;
 use std::sync::atomic::AtomicUsize;
 use std::sync::atomic::Ordering::SeqCst;
+#[cfg(feature = "parallel")]
 use std::sync::mpsc::*;
 use std::sync::Arc;
+#[cfg(feature = "parallel")]
 use std::thread;
 
 struct Candidate {
@@ -46,30 +48,46 @@ pub(crate) struct Evaluator {
     nth: AtomicUsize,
     best_candidate_size: Arc<AtomicMin>,
     /// images are sent to the thread for evaluation
+    #[cfg(feature = "parallel")]
     eval_send: SyncSender<Candidate>,
     // the thread helps evaluate images asynchronously
+    #[cfg(feature = "parallel")]
     eval_thread: thread::JoinHandle<Option<Candidate>>,
+    // in non-parallel mode, images are evaluated synchronously
+    #[cfg(not(feature = "parallel"))]
+    eval_best_candidate: RefCell<Option<Candidate>>,
 }
 
 impl Evaluator {
     pub fn new(deadline: Arc<Deadline>) -> Self {
+        #[cfg(feature = "parallel")]
         let (tx, rx) = sync_channel(4);
         Self {
             deadline,
             best_candidate_size: Arc::new(AtomicMin::new(None)),
             nth: AtomicUsize::new(0),
+            #[cfg(feature = "parallel")]
             eval_send: tx,
+            #[cfg(feature = "parallel")]
             eval_thread: thread::spawn(move || rx.into_iter().min_by_key(Candidate::cmp_key)),
+            #[cfg(not(feature = "parallel"))]
+            eval_best_candidate: RefCell::new(None),
         }
     }
 
     /// Wait for all evaluations to finish and return smallest reduction
     /// Or `None` if all reductions were worse than baseline.
+    #[cfg(feature = "parallel")]
     fn get_best_candidate(self) -> Option<Candidate> {
         drop(self.eval_send); // disconnect the sender, breaking the loop in the thread
         self.eval_thread.join().expect("eval thread")
     }
 
+    #[cfg(not(feature = "parallel"))]
+    fn get_best_candidate(self) -> Option<Candidate> {
+        self.eval_best_candidate.into_inner()
+    }
+
     pub fn get_result(self) -> Option<PngData> {
         self.get_best_candidate().map(|candidate| candidate.image)
     }
@@ -91,6 +109,7 @@ impl Evaluator {
         let best_candidate_size = self.best_candidate_size.clone();
         // sends it off asynchronously for compression,
         // but results will be collected via the message queue
+        #[cfg(feature = "parallel")]
         let eval_send = self.eval_send.clone();
         rayon::spawn(move || {
             let filters_iter = STD_FILTERS.par_iter().with_max_len(1);
@@ -126,8 +145,19 @@ impl Evaluator {
                         nth,
                     };
 
+                    #[cfg(feature = "parallel")]
+                    {
                         eval_send.send(new).expect("send");
                     }
+
+                    #[cfg(not(feature = "parallel"))]
+                    {
+                        match &mut *self.eval_best_candidate.borrow_mut() {
+                            Some(prev) if prev.cmp_key() < new.cmp_key() => {}
+                            best => *best = Some(new),
+                        }
+                    }
+                }
             });
         });
     }

src/lib.rs

@@ -13,7 +13,6 @@
 #![warn(clippy::range_plus_one)]
 #![allow(clippy::cognitive_complexity)]
 
-use num_cpus;
 #[cfg(feature = "parallel")]
 extern crate rayon;
 #[cfg(not(feature = "parallel"))]
@@ -206,10 +205,6 @@ pub struct Options {
     ///
     /// Default: `false`
     pub use_heuristics: bool,
-    /// Number of threads to use
-    ///
-    /// Default: number of CPU cores
-    pub threads: usize,
 
     /// Maximum amount of time to spend on optimizations.
     /// Further potential optimizations are skipped if the timeout is exceeded.
@@ -313,7 +308,6 @@ impl Default for Options {
             strip: Headers::None,
             deflate: Deflaters::Zlib,
             use_heuristics: false,
-            threads: num_cpus::get(),
             timeout: None,
         }
     }
@@ -321,12 +315,6 @@ impl Default for Options {
 
 /// Perform optimization on the input file using the options provided
 pub fn optimize(input: &InFile, output: &OutFile, opts: &Options) -> PngResult<()> {
-    // Initialize the thread pool with correct number of threads
-    #[cfg(feature = "parallel")]
-    let _ = rayon::ThreadPoolBuilder::new()
-        .num_threads(opts.threads)
-        .build_global();
-
     // Read in the file and try to decode as PNG.
     if opts.verbosity.is_some() {
         eprintln!("Processing: {}", input);
@@ -421,12 +409,6 @@ pub fn optimize(input: &InFile, output: &OutFile, opts: &Options) -> PngResult<(
 /// Perform optimization on the input file using the options provided, where the file is already
 /// loaded in-memory
 pub fn optimize_from_memory(data: &[u8], opts: &Options) -> PngResult<Vec<u8>> {
-    // Initialize the thread pool with correct number of threads
-    #[cfg(feature = "parallel")]
-    let _ = rayon::ThreadPoolBuilder::new()
-        .num_threads(opts.threads)
-        .build_global();
-
     // Read in the file and try to decode as PNG.
     if opts.verbosity.is_some() {
         eprintln!("Processing from memory");

src/main.rs

@@ -486,7 +486,12 @@ fn parse_opts_into_struct(
     }
 
     if let Some(x) = matches.value_of("threads") {
-        opts.threads = x.parse::<usize>().unwrap();
+        let threads = x.parse::<usize>().unwrap();
+
+        rayon::ThreadPoolBuilder::new()
+            .num_threads(threads)
+            .build_global()
+            .map_err(|err| err.to_string())?;
     }
 
     Ok((out_file, out_dir, opts))