Merge pull request #620 from capnproto/premature-eof-disconnect

Treat 'Premature EOF' error on async stream as DISCONNECTED.

c++/src/kj/async-io.c++

@@ -53,12 +53,14 @@ Promise<void> AsyncInputStream::read(void* buffer, size_t bytes) {
 
 Promise<size_t> AsyncInputStream::read(void* buffer, size_t minBytes, size_t maxBytes) {
   return tryRead(buffer, minBytes, maxBytes).then([=](size_t result) {
-    KJ_REQUIRE(result >= minBytes, "Premature EOF") {
+    if (result >= minBytes) {
+      return result;
+    } else {
+      kj::throwRecoverableException(KJ_EXCEPTION(DISCONNECTED, "stream disconnected prematurely"));
       // Pretend we read zeros from the input.
       memset(reinterpret_cast<byte*>(buffer) + result, 0, minBytes - result);
       return minBytes;
     }
-    return result;
   });
 }
 

c++/src/kj/compat/gzip.c++

@@ -54,7 +54,9 @@ Promise<size_t> GzipAsyncInputStream::readImpl(
     return inner.tryRead(buffer, 1, sizeof(buffer))
         .then([this,out,minBytes,maxBytes,alreadyRead](size_t amount) -> Promise<size_t> {
       if (amount == 0) {
-        KJ_REQUIRE(atValidEndpoint, "gzip compressed stream ended prematurely");
+        if (!atValidEndpoint) {
+          return KJ_EXCEPTION(DISCONNECTED, "gzip compressed stream ended prematurely");
+        }
         return alreadyRead;
       } else {
         ctx.next_in = buffer;