feat/wasm emscripten target

.github/workflows/ci.yml

@@ -44,6 +44,39 @@ jobs:
         run: pytest
         working-directory: pumpkin-py
 
+  wasm:
+    name: Build pumpkin-solver (wasm32-unknown-emscripten)
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      # cache Cargo registry & your target/ dir
+      - uses: actions/cache@v4
+        with:
+          path: |
+            ~/.cargo/registry/index/
+            ~/.cargo/registry/cache/
+            ~/.cargo/git/db/
+            target/
+          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+
+      # install Rust & add the Emscripten target
+      - uses: dtolnay/rust-toolchain@stable
+      - run: rustup target add wasm32-unknown-emscripten
+
+      # install Emscripten SDK & clang
+      - run: |
+          sudo apt-get update
+          sudo apt-get install -y emscripten clang
+
+      # build only pumpkin-solver for wasm
+      - name: Build pumpkin-solver wasm
+        run: |
+          cargo build \
+            --release \
+            --target wasm32-unknown-emscripten \
+            -p pumpkin-solver
+
   docs:
     name: Documentation
     runs-on: ubuntu-latest

pumpkin-solver/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pumpkin-solver"
-version = "0.2.0"
+version = "0.1.4"
 description = "The Pumpkin combinatorial optimisation solver library."
 readme = "../README.md"
 authors.workspace = true
@@ -15,10 +15,9 @@ bitfield = "0.14.0"
 enumset = "1.1.2"
 fnv = "1.0.3"
 rand = { version = "0.8.5", features = [ "small_rng", "alloc" ] }
-signal-hook = "0.3.17"
 once_cell = "1.19.0"
 downcast-rs = "1.2.1"
-drcp-format = { version = "0.2.1", path = "../drcp-format" }
+drcp-format = { version = "0.2.0", path = "../drcp-format" }
 convert_case = "0.6.0"
 itertools = "0.13.0"
 flatzinc = "0.3.21"
@@ -28,6 +27,12 @@ bitfield-struct = "0.9.2"
 num = "0.4.3"
 enum-map = "2.7.3"
 
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+signal-hook = "0.3.17"
+
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+getrandom = { version = "0.2", features = ["js"] }
+
 [dev-dependencies]
 clap = { version = "4.5.17", features = ["derive"] }
 env_logger = "0.10.0"

pumpkin-solver/build.rs

@@ -71,7 +71,18 @@ fn add_output_file<P: AsRef<Path>>(
     output_stem: &str,
 ) {
     let output_dir = output_dir.as_ref();
-    if is_msvc {
+    let target = std::env::var("TARGET").unwrap();
+    if target.contains("wasm32") {
+        // Output as a .wasm file when targeting WebAssembly.
+        let wasm_filename = format!("{output_stem}.wasm");
+        let output_file = output_dir.join(wasm_filename);
+        let _ = cmd.arg("-o").arg(output_file);
+
+        // Enable exceptions for Emscripten target
+        if target.contains("emscripten") {
+            let _ = cmd.arg("-fexceptions");
+        }
+    } else if is_msvc {
         let exe_name = format!("{output_stem}.exe");
 
         // The path to the object file.

pumpkin-solver/src/api/mod.rs

@@ -86,6 +86,7 @@ pub mod termination {
     //! the time budget is exceeded.
     pub use crate::engine::termination::combinator::*;
     pub use crate::engine::termination::indefinite::*;
+    #[cfg(not(target_arch = "wasm32"))]
     pub use crate::engine::termination::os_signal::*;
     pub use crate::engine::termination::time_budget::*;
     pub use crate::engine::termination::TerminationCondition;

pumpkin-solver/src/bin/pumpkin-solver/flatzinc/mod.rs

@@ -27,6 +27,9 @@ use pumpkin_solver::results::SatisfactionResult;
 use pumpkin_solver::results::SolutionReference;
 use pumpkin_solver::statistics::StatisticLogger;
 use pumpkin_solver::termination::Combinator;
+#[cfg(target_arch = "wasm32")]
+use pumpkin_solver::termination::Indefinite as OsSignalReplacement;
+#[cfg(not(target_arch = "wasm32"))]
 use pumpkin_solver::termination::OsSignal;
 use pumpkin_solver::termination::TerminationCondition;
 use pumpkin_solver::termination::TimeBudget;
@@ -83,10 +86,14 @@ pub(crate) fn solve(
 ) -> Result<(), FlatZincError> {
     let instance = File::open(instance)?;
 
-    let mut termination = Combinator::new(
-        OsSignal::install(),
-        time_limit.map(TimeBudget::starting_now),
-    );
+    #[cfg(not(target_arch = "wasm32"))]
+    let signal_condition = OsSignal::install();
+
+    #[cfg(target_arch = "wasm32")]
+    let signal_condition = OsSignalReplacement;
+
+    let mut termination =
+        Combinator::new(signal_condition, time_limit.map(TimeBudget::starting_now));
 
     let instance = parse_and_compile(&mut solver, instance, options)?;
     let outputs = instance.outputs.clone();

pumpkin-solver/src/engine/termination/mod.rs

@@ -5,6 +5,7 @@
 
 pub(crate) mod combinator;
 pub(crate) mod indefinite;
+#[cfg(not(target_arch = "wasm32"))]
 pub(crate) mod os_signal;
 pub(crate) mod time_budget;