1 files changed, 62 insertions, 0 deletions
diff --git a/services/sandbox-exec/lib/exec.js b/services/sandbox-exec/lib/exec.js
new file mode 100644
index 0000000..e37dbb5
--- /dev/null
+++ b/services/sandbox-exec/lib/exec.js
@@ -0,0 +1,62 @@
+import PHPWasm from './php-wasm.js'
+
+process.once('message', async ({ code, input }) => {
+  const PRELUDE = `
+  define('STDIN', fopen('php://stdin', 'r'));
+  define('STDOUT', fopen('php://stdout', 'r'));
+  define('STDERR', fopen('php://stderr', 'r'));
+
+  `;
+  const BUFFER_MAX = 1024 * 1024 * 1;
+
+  let stdinPos = 0; // bytewise
+  let stdinBuf = Buffer.from(input);
+  let stdoutPos = 0; // bytewise
+  let stdoutBuf = Buffer.alloc(BUFFER_MAX);
+  let stderrPos = 0; // bytewise
+  let stderrBuf = Buffer.alloc(BUFFER_MAX);
+
+  const { ccall } = await PHPWasm({
+    stdin: () => {
+      if (stdinBuf.length <= stdinPos) {
+        return null;
+      }
+      return stdinBuf.readUInt8(stdinPos++);
+    },
+    stdout: (asciiCode) => {
+      if (asciiCode === null) {
+        return; // flush
+      }
+      if (BUFFER_MAX <= stdoutPos) {
+        return; // ignore
+      }
+      if (asciiCode < 0) {
+        asciiCode += 256;
+      }
+      stdoutBuf.writeUInt8(asciiCode, stdoutPos++);
+    },
+    stderr: (asciiCode) => {
+      if (asciiCode === null) {
+        return; // flush
+      }
+      if (BUFFER_MAX <= stderrPos) {
+        return; // ignore
+      }
+      if (asciiCode < 0) {
+        asciiCode += 256;
+      }
+      stderrBuf.writeUInt8(asciiCode, stderrPos++);
+    },
+  });
+
+  const result = ccall(
+    'php_wasm_run',
+    'number', ['string'],
+    [PRELUDE + code],
+  );
+  process.send({
+    status: result === 0 ? 'AC' : 'RE',
+    stdout: stdoutBuf.subarray(0, stdoutPos).toString(),
+    stderr: stderrBuf.subarray(0, stderrPos).toString(),
+  });
+});