download libwasi_vfs.a on demand at build-time

Author: kateinoigakukun

lib/ruby_wasm/build_system/product.rb

@@ -4,4 +4,5 @@
 require_relative "product/baseruby"
 require_relative "product/zlib"
 require_relative "product/libyaml"
+require_relative "product/wasi_vfs"
 require_relative "product/crossruby"

lib/ruby_wasm/build_system/product/crossruby.rb

@@ -165,6 +165,11 @@ def with_zlib(zlib)
       @dep_tasks << zlib.install_task
     end
 
+    def with_wasi_vfs(wasi_vfs)
+      @wasi_vfs = wasi_vfs
+      @dep_tasks << wasi_vfs.install_task
+    end
+
     def dest_dir
       File.join(@rubies_dir, name)
     end
@@ -209,9 +214,7 @@ def configure_args(build_triple, toolchain)
 
       case target
       when "wasm32-unknown-wasi"
-        unless toolchain.lib_wasi_vfs_a.nil?
-          xldflags << toolchain.lib_wasi_vfs_a
-        end
+        xldflags << @wasi_vfs.lib_wasi_vfs_a if @wasi_vfs
       when "wasm32-unknown-emscripten"
         ldflags.concat(%w[-s MODULARIZE=1])
         args.concat(%w[CC=emcc LD=emcc AR=emar RANLIB=emranlib])

lib/ruby_wasm/build_system/product/wasi_vfs.rb

@@ -0,0 +1,45 @@
+require "rake"
+require_relative "./product"
+
+module RubyWasm
+  class WasiVfsProduct < BuildProduct
+    attr_reader :install_task
+
+    WASI_VFS_VERSION = "0.1.1"
+
+    def initialize(build_dir)
+      @build_dir = build_dir
+    end
+
+    def lib_product_build_dir
+      File.join(
+        @build_dir,
+        "wasm32-unknown-wasi",
+        "wasi-vfs-#{WASI_VFS_VERSION}"
+      )
+    end
+
+    def lib_wasi_vfs_a
+      File.join(lib_product_build_dir, "libwasi_vfs.a")
+    end
+
+    def name
+      lib_product_build_dir
+    end
+
+    def define_task
+      @install_task =
+        file(lib_wasi_vfs_a) do
+          require "tmpdir"
+          lib_wasi_vfs_url =
+            "https://github.com/kateinoigakukun/wasi-vfs/releases/download/v#{WASI_VFS_VERSION}/libwasi_vfs-wasm32-unknown-unknown.zip"
+          Dir.mktmpdir do |tmpdir|
+            sh "curl -L #{lib_wasi_vfs_url} -o #{tmpdir}/libwasi_vfs.zip"
+            sh "unzip #{tmpdir}/libwasi_vfs.zip -d #{tmpdir}"
+            mkdir_p File.dirname(lib_wasi_vfs_a)
+            mv File.join(tmpdir, "libwasi_vfs.a"), lib_wasi_vfs_a
+          end
+        end
+    end
+  end
+end

lib/ruby_wasm/rake_task.rb

@@ -43,6 +43,7 @@ def initialize(
       add_product RubyWasm::LibYAMLProduct.new(@build_dir, @target, @toolchain)
     @zlib =
       add_product RubyWasm::ZlibProduct.new(@build_dir, @target, @toolchain)
+    @wasi_vfs = add_product RubyWasm::WasiVfsProduct.new(@build_dir)
     @source = add_product RubyWasm::BuildSource.new(src, @build_dir)
     @baseruby = add_product RubyWasm::BaseRubyProduct.new(@build_dir, @source)
 
@@ -64,6 +65,7 @@ def initialize(
 
     @crossruby.with_libyaml @libyaml
     @crossruby.with_zlib @zlib
+    @crossruby.with_wasi_vfs @wasi_vfs
 
     @crossruby.define_task
   end