diff options
| -rw-r--r-- | src/libstore/download.cc | 45 |
1 files changed, 26 insertions, 19 deletions
diff --git a/src/libstore/download.cc b/src/libstore/download.cc index 13913d031..f44f1836b 100644 --- a/src/libstore/download.cc +++ b/src/libstore/download.cc @@ -710,11 +710,12 @@ void Downloader::download(DownloadRequest && request, Sink & sink) /* If the buffer is full, then go to sleep until the calling thread wakes us up (i.e. when it has removed data from the - buffer). Note: this does stall the download thread. */ - while (state->data.size() > 1024 * 1024) { - if (state->quit) return; + buffer). We don't wait forever to prevent stalling the + download thread. (Hopefully sleeping will throttle the + sender.) */ + if (state->data.size() > 1024 * 1024) { debug("download buffer is full; going to sleep"); - state.wait(state->request); + state.wait_for(state->request, std::chrono::seconds(10)); } /* Append data to the buffer and wake up the calling @@ -736,30 +737,36 @@ void Downloader::download(DownloadRequest && request, Sink & sink) state->request.notify_one(); }}); - auto state(_state->lock()); - while (true) { checkInterrupt(); - /* If no data is available, then wait for the download thread - to wake us up. */ - if (state->data.empty()) { + std::string chunk; + + /* Grab data if available, otherwise wait for the download + thread to wake us up. */ + { + auto state(_state->lock()); + + while (state->data.empty()) { - if (state->quit) { - if (state->exc) std::rethrow_exception(state->exc); - break; + if (state->quit) { + if (state->exc) std::rethrow_exception(state->exc); + return; + } + + state.wait(state->avail); } - state.wait(state->avail); - } + chunk = std::move(state->data); - /* If data is available, then flush it to the sink and wake up - the download thread if it's blocked on a full buffer. */ - if (!state->data.empty()) { - sink((unsigned char *) state->data.data(), state->data.size()); - state->data.clear(); state->request.notify_one(); } + + /* Flush the data to the sink and wake up the download thread + if it's blocked on a full buffer. We don't hold the state + lock while doing this to prevent blocking the download + thread if sink() takes a long time. */ + sink((unsigned char *) chunk.data(), chunk.size()); } } |