1 files changed, 62 insertions, 0 deletions
diff --git a/runtime/js/12_io.js b/runtime/js/12_io.js
index fe815c7ed..aa153e9fd 100644
--- a/runtime/js/12_io.js
+++ b/runtime/js/12_io.js
@@ -123,6 +123,66 @@
     return result;
   }
 
+  const READ_PER_ITER = 32 * 1024;
+
+  async function readAll(r) {
+    const buffers = [];
+
+    while (true) {
+      const buf = new Uint8Array(READ_PER_ITER);
+      const read = await r.read(buf);
+      if (typeof read == "number") {
+        buffers.push(new Uint8Array(buf.buffer, 0, read));
+      } else {
+        break;
+      }
+    }
+
+    let totalLen = 0;
+    for (const buf of buffers) {
+      totalLen += buf.byteLength;
+    }
+
+    const contents = new Uint8Array(totalLen);
+
+    let n = 0;
+    for (const buf of buffers) {
+      contents.set(buf, n);
+      n += buf.byteLength;
+    }
+
+    return contents;
+  }
+
+  function readAllSync(r) {
+    const buffers = [];
+
+    while (true) {
+      const buf = new Uint8Array(READ_PER_ITER);
+      const read = r.readSync(buf);
+      if (typeof read == "number") {
+        buffers.push(new Uint8Array(buf.buffer, 0, read));
+      } else {
+        break;
+      }
+    }
+
+    let totalLen = 0;
+    for (const buf of buffers) {
+      totalLen += buf.byteLength;
+    }
+
+    const contents = new Uint8Array(totalLen);
+
+    let n = 0;
+    for (const buf of buffers) {
+      contents.set(buf, n);
+      n += buf.byteLength;
+    }
+
+    return contents;
+  }
+
   window.__bootstrap.io = {
     iterSync,
     iter,
@@ -132,5 +192,7 @@
     readSync,
     write,
     writeSync,
+    readAll,
+    readAllSync,
   };
 })(this);