[fix] #1 js bindings

Signed-off-by: Anton Nesterov <anton@demiurg.io>

dal/Binding.ts

@@ -1,7 +1,11 @@
 import { createRequire } from "node:module";
 const require = createRequire(import.meta.url);
+type RowIterator = {
+  next: () => Buffer;
+  free: () => void;
+};
 type SQLite = {
   InitSQLite: (pragmas: Buffer) => void;
-  Handle: (input: Buffer) => Buffer;
+  RowIterator: (input: Buffer) => RowIterator;
 };
 export default require("../build/Release/dal.node") as SQLite;

dal/CBuilder.ts

@@ -18,14 +18,19 @@ export default class CBuilder<
     super({ database: opts.database, url: "" });
   }
   /**
-   * Not really an iterator, since addonn allocates memory for all rows
+   * TODO: handle responses
-   * but returns an iterator
    */
   async *Rows<T = InstanceType<I>>(): AsyncGenerator<T> {
     this.formatRequest();
     const req = Buffer.from(encodeRequest(this.request));
-    const response = Binding.Handle(req);
+    const iter = Binding.RowIterator(req);
+    for (;;) {
+      const response = iter.next();
       const rows = decodeRows(response);
+      if (rows.length === 0) {
+        iter.free();
+        break;
+      }
       for (const row of rows) {
         if (this.headerRow === null) {
           this.headerRow = row.r;
@@ -34,6 +39,7 @@ export default class CBuilder<
         yield this.formatRow(row.r);
       }
     }
+  }
   async Query<T = InstanceType<I>>(): Promise<T[]> {
     const rows = this.Rows();
     const result: T[] = [];
@@ -45,7 +51,8 @@ export default class CBuilder<
   async Exec(): Promise<ExecResult> {
     this.formatRequest();
     const req = Buffer.from(encodeRequest(this.request));
-    const response = Binding.Handle(req);
+    const iter = Binding.RowIterator(req);
+    const response = iter.next();
     return decodeResponse(response);
   }
 }