From de8356ce3261e5ac8562afeed53d69ff3fa167b3 Mon Sep 17 00:00:00 2001
From: Zicklag <zicklag@katharostech.com>
Date: Tue, 31 Dec 2024 20:57:28 -0600
Subject: [PATCH] fix: fix possible non-termination in `ingest_drop()`.

---
 src/sideload/ingest_drop.ts | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/sideload/ingest_drop.ts b/src/sideload/ingest_drop.ts
index 123b0f9..03e3767 100644
--- a/src/sideload/ingest_drop.ts
+++ b/src/sideload/ingest_drop.ts
@@ -45,6 +45,13 @@ export type IngestDropOpts<
   decodeStreamAuthorisationToken: StreamDecoder<AuthorisationToken>;
 };
 
+async function* terminatingFifoIterator<T>(fifo: FIFO<T | undefined>) {
+  for await (const chunk of fifo) {
+    if (!chunk) break;
+    yield chunk;
+  }
+}
+
 /** Decrypt an encrypted [drop](https://willowprotocol.org/specs/sideloading/index.html#drop) and ingest its contents into a {@linkcode Store} of the corresponding namespace.
  *
  * @returns The {@linkcode Store} which ingested the drop's contents.
@@ -135,13 +142,16 @@ export async function ingestDrop<
       );
     }
 
-    const fifo = new FIFO<Uint8Array>();
+    const fifo = new FIFO<Uint8Array | undefined>();
 
-    const payloadIngestPromise = store.ingestPayload({
-      path: entry.path,
-      subspace: entry.subspaceId,
-      timestamp: entry.timestamp,
-    }, fifo);
+    const payloadIngestPromise = store.ingestPayload(
+      {
+        path: entry.path,
+        subspace: entry.subspaceId,
+        timestamp: entry.timestamp,
+      },
+      terminatingFifoIterator(fifo)
+    );
 
     let remainingBytes = entry.payloadLength;
 
@@ -165,6 +175,8 @@ export async function ingestDrop<
       }
     }
 
+    fifo.push(undefined);
+
     const payloadIngestResult = await payloadIngestPromise;
 
     if (payloadIngestResult.kind === "failure") {