remove redundant buffer overflow checks

Author: glasstiger

src/buffer/base.ts

@@ -80,11 +80,7 @@ abstract class SenderBufferBase implements SenderBuffer {
       );
     }
     this.bufferSize = bufferSize;
-    // Allocating an extra byte because Buffer.write() does not fail if the length of the data to be written is
-    // longer than the size of the buffer. It simply just writes whatever it can, and returns.
-    // If we can write into the extra byte, that indicates buffer overflow.
-    // See the check in the write() function.
-    const newBuffer = Buffer.alloc(this.bufferSize + 1, 0);
+    const newBuffer = Buffer.alloc(this.bufferSize, 0);
     if (this.buffer) {
       this.buffer.copy(newBuffer);
     }
@@ -378,32 +374,14 @@ abstract class SenderBufferBase implements SenderBuffer {
 
   protected write(data: string) {
     this.position += this.buffer.write(data, this.position);
-    if (this.position > this.bufferSize) {
-      // should never happen, if checkCapacity() is correctly used
-      throw new Error(
-        `Buffer overflow [position=${this.position}, bufferSize=${this.bufferSize}]`,
-      );
-    }
   }
 
   protected writeByte(data: number) {
     this.position = this.buffer.writeInt8(data, this.position);
-    if (this.position > this.bufferSize) {
-      // should never happen, if checkCapacity() is correctly used
-      throw new Error(
-        `Buffer overflow [position=${this.position}, bufferSize=${this.bufferSize}]`,
-      );
-    }
   }
 
   protected writeDouble(data: number) {
     this.position = this.buffer.writeDoubleLE(data, this.position);
-    if (this.position > this.bufferSize) {
-      // should never happen, if checkCapacity() is correctly used
-      throw new Error(
-        `Buffer overflow [position=${this.position}, bufferSize=${this.bufferSize}]`,
-      );
-    }
   }
 
   private writeEscaped(data: string, quoted = false) {

test/sender.buffer.test.ts

@@ -732,7 +732,7 @@ describe("Sender message builder test suite (anything not covered in client inte
     await sender.close();
   });
 
-  it("extends the size of the buffer if data does not fit", async function () {
+  it("extends the size of the buffer v1 if data does not fit", async function () {
     const sender = new Sender({
       protocol: "tcp",
       protocol_version: "1",
@@ -767,6 +767,39 @@ describe("Sender message builder test suite (anything not covered in client inte
     await sender.close();
   });
 
+  it("extends the size of the buffer v2 if data does not fit", async function () {
+    const sender = new Sender({
+      protocol: "tcp",
+      protocol_version: "2",
+      host: "host",
+      init_buf_size: 8,
+    });
+    expect(bufferSize(sender)).toBe(8);
+    expect(bufferPosition(sender)).toBe(0);
+    sender.table("tableName");
+    expect(bufferSize(sender)).toBe(24);
+    expect(bufferPosition(sender)).toBe("tableName".length);
+    sender.floatColumn("floatField", 123.456);
+    expect(bufferSize(sender)).toBe(48);
+    expect(bufferPosition(sender)).toBe("tableName floatField=".length + 10);
+    sender.stringColumn("strField", "hoho");
+    expect(bufferSize(sender)).toBe(96);
+    expect(bufferPosition(sender)).toBe(
+      "tableName floatField=".length + 10 + ',strField="hoho"'.length,
+    );
+    await sender.atNow();
+    expect(bufferSize(sender)).toBe(96);
+    expect(bufferPosition(sender)).toBe(
+      "tableName floatField=".length + 10 + ',strField="hoho"\n'.length,
+    );
+    expect(bufferContentHex(sender)).toBe(
+      toHex("tableName floatField=") +
+        " 3d 10 77 be 9f 1a 2f dd 5e 40 " +
+        toHex(',strField="hoho"\n'),
+    );
+    await sender.close();
+  });
+
   it("throws exception if tries to extend the size of the buffer above max buffer size", async function () {
     const sender = await Sender.fromConfig(
       "tcp::addr=host;init_buf_size=8;max_buf_size=64;",
@@ -838,6 +871,21 @@ function bufferContent(sender: Sender) {
   return sender.buffer.toBufferView().toString();
 }
 
+function bufferContentHex(sender: Sender) {
+  // @ts-expect-error - Accessing private field
+  return toHexString(sender.buffer.toBufferView());
+}
+
+function toHex(str: string) {
+  return toHexString(Buffer.from(str));
+}
+
+function toHexString(buffer: Buffer) {
+  return Array.from(buffer)
+    .map((b) => b.toString(16).padStart(2, "0"))
+    .join(" ");
+}
+
 function bufferSize(sender: Sender) {
   // @ts-expect-error - Accessing private field
   return sender.buffer.bufferSize;