Added support for wasm32-wasi target

Author: OtaK

.github/workflows/main.yml

@@ -59,9 +59,10 @@ jobs:
         - target: x86_64-pc-windows-gnu
           rust: stable
           os: ubuntu-latest
-        # - target: asmjs-unknown-emscripten
-        #   rust: stable
-        #   os: ubuntu-latest
+        - target: wasm32-wasi
+          rust: stable
+          os: ubuntu-latest
+          crt_static: yes
         - target: i686-pc-windows-msvc
           rust: stable-i686-msvc
           os: windows-2016

ci/docker/asmjs-unknown-emscripten/Dockerfile

@@ -8,8 +8,15 @@ if [ "$1" = "aarch64-apple-darwin" ] ; then
   export CARGO_TARGET_AARCH64_APPLE_DARWIN_RUNNER=echo
 fi
 
-cargo test --manifest-path "$testcrate_dir/Cargo.toml" --target $1 -vv
-cargo test --manifest-path "$testcrate_dir/Cargo.toml" --target $1 -vv --release
+if [ "$1" = "wasm32-wasi" ] ; then
+  cargo install cargo-wasi
+  curl https://wasmtime.dev/install.sh -sSf | bash
+  cargo wasi test --manifest-path "$testcrate_dir/Cargo.toml" -vv
+  cargo wasi test --manifest-path "$testcrate_dir/Cargo.toml" -vv --release
+else
+  cargo test --manifest-path "$testcrate_dir/Cargo.toml" --target $1 -vv
+  cargo test --manifest-path "$testcrate_dir/Cargo.toml" --target $1 -vv --release
+fi
 
 if [ "$1" = "x86_64-unknown-linux-gnu" ] ; then
   cargo test --manifest-path "$testcrate_dir/Cargo.toml" --target $1 -vv --all-features

ci/run.sh

@@ -423,6 +423,56 @@ impl Build {
                 configure.arg("-D__STDC_NO_ATOMICS__");
             }
 
+            if target.contains("wasi") {
+                configure.args([
+                    // Termios isn't available whatsoever on WASM/WASI so we disable that
+                    // fatal error: 'termios.h' file not found
+                    "no-ui-console",
+                    // WASI doesn't support UNIX sockets so we preemptively disable it
+                    "no-sock",
+                    // WASI doesn't have a concept of syslog, so we disable it
+                    // fatal error: 'syslog.h' file not found
+                    "-DNO_SYSLOG",
+                    // wasm lacks signal support; to enable minimal signal emulation, compile with
+                    // -D_WASI_EMULATED_SIGNAL and link with -lwasi-emulated-signal
+                    "-D_WASI_EMULATED_SIGNAL",
+                    // WASI lacks process-associated clocks; to enable emulation of the `times` function using the wall
+                    // clock, which isn't sensitive to whether the program is running or suspended, compile with
+                    // -D_WASI_EMULATED_PROCESS_CLOCKS and link with -lwasi-emulated-process-clocks
+                    "-D_WASI_EMULATED_PROCESS_CLOCKS",
+                    // WASI lacks a true mmap; to enable minimal mmap emulation, compile
+                    // with -D_WASI_EMULATED_MMAN and link with -lwasi-emulated-mman
+                    "-D_WASI_EMULATED_MMAN",
+                    // WASI lacks process identifiers; to enable emulation of the `getpid` function using a
+                    // placeholder value, which doesn't reflect the host PID of the program, compile with
+                    // -D_WASI_EMULATED_GETPID and link with -lwasi-emulated-getpid
+                    "-D_WASI_EMULATED_GETPID",
+                    // ----------
+                    // The following arguments are taken from:
+                    // https://github.com/wapm-packages/OpenSSL/blob/master/build.sh#L21
+                    // Since this is a successful and reliable source for configuring WASM/I builds.
+                    // I will try to explain those to the best of my ability though.
+                    // ----------
+                    // WASI doesn't support (p)threads. Disabling preemptively.
+                    "no-threads",
+                    // WASI/WASM aren't really friends with ASM, so we disable it as well.
+                    "no-asm",
+                    // Disables the AFALG engine (AFALG-ENGine)
+                    // Since AFALG depends on `AF_ALG` support on the linux kernel side
+                    // it makes sense that we can't use it.
+                    "no-afalgeng",
+                    "-DOPENSSL_NO_AFALGENG=1",
+                    // ? Do we really want to always build statically for wasm? I guess yes?
+                    "static",
+                    // No fork(1) support in WASI, so we disable it
+                    "-DHAVE_FORK=0",
+                    "-DOPENSSL_NO_SPEED=1",
+                    "-DOPENSSL_SYS_NETWARE",
+                    "-DSIG_DFL=0",
+                    "-DSIG_IGN=0",
+                ]);
+            }
+
             if target.contains("musl") {
                 // Hack around openssl/openssl#7207 for now
                 configure.arg("-DOPENSSL_NO_SECURE_MEMORY");

src/lib.rs

@@ -6,10 +6,15 @@ extern "C" {
     pub fn OpenSSL_version_num() -> c_ulong;
 }
 
-#[test]
-fn version_works() {
-    unsafe {
-        println!("{:#x}", OpenSSL_version_num());
-        assert!(OpenSSL_version_num() > 0);
+#[cfg(test)]
+mod tests {
+    use super::OpenSSL_version_num;
+
+    #[test]
+    fn version_works() {
+        unsafe {
+            println!("{:#x}", OpenSSL_version_num());
+            assert!(OpenSSL_version_num() > 0);
+        }
     }
 }