wasm improvements

implementations/Crafter.Build-Clang.cpp

@@ -471,7 +471,7 @@ BuildResult Crafter::Build(Configuration& config, std::unordered_map<fs::path, s
         // -mllvm is consumed by codegen but not the link driver, which is the
         // same command line; quiet the unused-flag warning rather than split
         // compile and link commands.
-        command += " -fno-exceptions -fno-c++-static-destructors -mllvm -wasm-enable-sjlj -D_WASI_EMULATED_SIGNAL -Wno-unused-command-line-argument";
+        command += " -fno-exceptions -msimd128 -fno-c++-static-destructors -mllvm -wasm-enable-sjlj -D_WASI_EMULATED_SIGNAL -Wno-unused-command-line-argument";
     }
     if (config.target == "x86_64-w64-mingw32") {
         // mingw libstdc++ defines TLS via __emutls_v.* (emulated TLS); without
@@ -621,16 +621,32 @@ BuildResult Crafter::Build(Configuration& config, std::unordered_map<fs::path, s
         command += " -O3";
     }
 
+    // Same target-aware setup as the C++ compile path (line 459-): wasm32
+    // rejects -march, silently ignores -mtune, and needs --sysroot to find
+    // wasi-libc headers. Build the prefix once so all C compiles share it.
+    const bool cIsWasm = config.target.starts_with("wasm32");
+    std::string cArchFlags = cIsWasm
+        ? std::string()
+        : std::format(" -march={} -mtune={}", config.march, config.mtune);
+    if (!config.sysroot.empty()) {
+        cArchFlags += std::format(" --sysroot={}", config.sysroot);
+    }
+    if (cIsWasm) {
+        // Matches the C++ path's wasi flag set so any libc shim defines
+        // (e.g. _WASI_EMULATED_SIGNAL → signal.h shims) are visible to
+        // C dependencies that drag in signal.h transitively.
+        cArchFlags += " -D_WASI_EMULATED_SIGNAL";
+    }
     for (const fs::path& cFile : config.cFiles) {
         files += std::format(" {}_source.o ", (buildDir / cFile.filename()).string());
         const std::string objPath = (buildDir / cFile.filename()).string() + "_source.o";
         const std::string srcPath = cFile.string() + ".c";
         if (!fs::exists(objPath) || (fs::exists(srcPath) && fs::last_write_time(srcPath) > fs::last_write_time(objPath))) {
-            threads.emplace_back([&cFile, &buildDir, &buildError, &buildCancelled, &config, &includeFlags, &defineFlags, &userFlags]() {
+            threads.emplace_back([&cFile, &buildDir, &buildError, &buildCancelled, &config, &includeFlags, &defineFlags, &userFlags, &cArchFlags]() {
                 Progress::Task task(std::format("Compiling {}.c", cFile.filename().string()));
                 if (buildCancelled.load(std::memory_order_relaxed)) return;
 
-                std::string result = RunCommand(std::format("clang {}.c --target={} -march={} -mtune={} -O3 -c{}{}{} -o {}_source.o", cFile.string(), config.target, config.march, config.mtune, includeFlags, defineFlags, userFlags, (buildDir / cFile.filename()).string()));
+                std::string result = RunCommand(std::format("clang {}.c --target={}{} -O3 -c{}{}{} -o {}_source.o", cFile.string(), config.target, cArchFlags, includeFlags, defineFlags, userFlags, (buildDir / cFile.filename()).string()));
                 if (result.empty()) return;
 
                 bool expected = false;
@@ -1034,16 +1050,79 @@ void Crafter::EnableWasiBrowserRuntime(Configuration& cfg) {
     fs::create_directories(htmlOutDir);
     fs::path htmlPath = htmlOutDir / "index.html";
 
+    // Walk the dep graph for env-style JS bridges that need to load BEFORE
+    // runtime.js so they can populate `window.crafter_webbuild_env`. Any
+    // `*.js` entry in a (transitive) dep's `cfg.files` qualifies — the
+    // file is already going to be copied into the consumer's bin dir, we
+    // just need its basename for a `<script src=...>` tag.
+    std::vector<std::string> envScripts;
+    std::unordered_set<Configuration*> seen;
+    std::function<void(Configuration*)> walk = [&](Configuration* c) {
+        if (!c || !seen.insert(c).second) return;
+        for (const fs::path& f : c->files) {
+            if (f.extension() == ".js" && f.filename() != "runtime.js") {
+                std::string name = f.filename().string();
+                if (std::find(envScripts.begin(), envScripts.end(), name) == envScripts.end()) {
+                    envScripts.push_back(std::move(name));
+                }
+            }
+        }
+        for (Configuration* dep : c->dependencies) walk(dep);
+    };
+    walk(&cfg);
+
+    std::string envScriptTags;
+    for (const std::string& name : envScripts) {
+        envScriptTags += std::format("        <script src=\"{}\" type=\"module\"></script>\n", name);
+    }
+
+    // Walk the dep graph again for non-JS assets — these get pre-loaded by
+    // runtime.js into an in-memory VFS so the wasm's std::ifstream et al.
+    // can actually read them (the wasi-runtime in this repo otherwise
+    // stubs every fd syscall to zero). The manifest lists basenames only;
+    // each file lives next to the .wasm in the bin dir.
+    std::vector<std::string> assetFiles;
+    seen.clear();
+    std::function<void(Configuration*)> walkAssets = [&](Configuration* c) {
+        if (!c || !seen.insert(c).second) return;
+        for (const fs::path& f : c->files) {
+            std::string ext = f.extension().string();
+            if (ext == ".js" || ext == ".html") continue;
+            if (f.filename() == "runtime.js") continue;
+            std::string name = f.filename().string();
+            if (name.empty()) continue;
+            if (std::find(assetFiles.begin(), assetFiles.end(), name) == assetFiles.end()) {
+                assetFiles.push_back(std::move(name));
+            }
+        }
+        for (Configuration* dep : c->dependencies) walkAssets(dep);
+    };
+    walkAssets(&cfg);
+
+    fs::path manifestPath = htmlOutDir / "files.json";
+    {
+        std::ofstream m(manifestPath);
+        m << "[";
+        for (std::size_t i = 0; i < assetFiles.size(); ++i) {
+            if (i) m << ",";
+            m << "\"" << assetFiles[i] << "\"";
+        }
+        m << "]";
+    }
+
     std::ifstream in(htmlTemplate);
     std::stringstream buf;
     buf << in.rdbuf();
-    std::string html = std::regex_replace(buf.str(), std::regex(R"(\{\{WASM\}\})"), cfg.outputName + ".wasm");
+    std::string html = buf.str();
+    html = std::regex_replace(html, std::regex(R"(\{\{WASM\}\})"), cfg.outputName + ".wasm");
+    html = std::regex_replace(html, std::regex(R"(\{\{ENV_SCRIPTS\}\})"), envScriptTags);
     std::ofstream out(htmlPath);
     out << html;
     out.close();
 
     cfg.files.push_back(runtimeJs);
     cfg.files.push_back(htmlPath);
+    cfg.files.push_back(manifestPath);
 }
 
 std::string Crafter::HostTarget() {
@@ -1087,6 +1166,15 @@ ArgQuery Crafter::ApplyStandardArgs(Configuration& cfg, std::span<const std::str
     }
     if (sawLib && cfg.type == ConfigurationType::Executable) cfg.type = ConfigurationType::LibraryStatic;
     if (sawShared && cfg.type == ConfigurationType::LibraryStatic) cfg.type = ConfigurationType::LibraryDynamic;
+    // WASI sysroot autodetect, applied at config-load time so the VariantId
+    // includes it. (Build() also runs this once more for callers that bypassed
+    // ApplyStandardArgs, but doing it here makes dep PcmDirs consistent
+    // between the consumer's command-construction and the dep's own build.)
+    #ifdef CRAFTER_BUILD_CONFIGURATION_TARGET_x86_64_pc_linux_gnu
+    if (cfg.sysroot.empty() && cfg.target.starts_with("wasm32")) {
+        cfg.sysroot = "/usr/share/wasi-sysroot";
+    }
+    #endif
     return ArgQuery{args};
 }
 
@@ -1234,11 +1322,76 @@ int Crafter::Run(int argc, char** argv) {
             } else if (config.target == "x86_64-w64-mingw32" || config.target == "x86_64-pc-windows-msvc") {
                 artifact += ".exe";
             }
+            artifact = fs::absolute(artifact);
+            fs::path absDir = fs::absolute(dir);
+
+            // wasm targets need either a wasm runtime (wasi-cli) or an HTTP
+            // server (browser build with index.html). std::system on the
+            // .wasm path goes nowhere useful — replace with detection.
+            if (config.target.starts_with("wasm32")) {
+                bool browserBuild = fs::exists(absDir / "index.html");
+                auto have = [](std::string_view exe) {
+#ifdef _WIN32
+                    std::string probe = std::format("where {} > NUL 2>&1", exe);
+#else
+                    std::string probe = std::format("command -v {} > /dev/null 2>&1", exe);
+#endif
+                    return std::system(probe.c_str()) == 0;
+                };
+                if (browserBuild) {
+                    // Try installed HTTP servers in priority order: lightweight
+                    // / dependency-free first, ad-hoc ones last. Foreground
+                    // (Ctrl-C to stop); we exec, not fork.
+                    const int port = 8080;
+                    std::string cmd;
+                    std::string_view picked;
+                    if (have("caddy")) {
+                        picked = "caddy";
+                        cmd = std::format("caddy file-server --listen :{} --root {}", port, absDir.string());
+                    } else if (have("python3")) {
+                        picked = "python3";
+                        cmd = std::format("python3 -m http.server --directory {} {}", absDir.string(), port);
+                    } else if (have("python")) {
+                        picked = "python";
+                        cmd = std::format("python -m http.server --directory {} {}", absDir.string(), port);
+                    } else if (have("php")) {
+                        picked = "php";
+                        cmd = std::format("php -S 0.0.0.0:{} -t {}", port, absDir.string());
+                    } else if (have("ruby")) {
+                        picked = "ruby";
+                        cmd = std::format("ruby -run -e httpd {} -p{}", absDir.string(), port);
+                    } else if (have("busybox")) {
+                        picked = "busybox httpd";
+                        cmd = std::format("busybox httpd -f -p {} -h {}", port, absDir.string());
+                    } else if (have("npx")) {
+                        picked = "npx http-server";
+                        cmd = std::format("npx --yes http-server {} -p {} --silent", absDir.string(), port);
+                    } else {
+                        std::println(std::cerr,
+                            "-r wasm: no HTTP server found in PATH. Install one of: "
+                            "caddy, python3, python, php, ruby, busybox, npx (Node.js).");
+                        return 1;
+                    }
+                    std::println("serving {} via {} at http://localhost:{}/", absDir.string(), picked, port);
+                    return std::system(cmd.c_str()) == 0 ? 0 : 1;
+                }
+                // wasi-cli wasm — needs a standalone runtime.
+                if (have("wasmtime")) {
+                    return std::system(std::format("wasmtime {}", artifact.string()).c_str()) == 0 ? 0 : 1;
+                }
+                if (have("wasmer")) {
+                    return std::system(std::format("wasmer run {}", artifact.string()).c_str()) == 0 ? 0 : 1;
+                }
+                std::println(std::cerr,
+                    "-r wasm: no wasm runtime found in PATH. Install wasmtime or wasmer, "
+                    "or call EnableWasiBrowserRuntime(cfg) in project.cpp for a browser build.");
+                return 1;
+            }
+
             // Resolve to absolute — cmd.exe on Windows mishandles a leading
             // "./" by trying to interpret it as a command. system() invokes
             // through cmd /c, so the relative-prefixed path makes cmd error
             // with "'.' is not recognized as an internal or external command".
-            artifact = fs::absolute(artifact);
             // Run from the artifact's own directory so relative file opens
             // (shaders, assets copied alongside the exe via cfg.files) resolve
             // against the bin dir rather than the user's cwd. We exit the