update_engine: add logs and metrics for libcurl errors
curl_multi_perform may return code that is neither CURLM_OK or
CURLM_CALL_MULTI_PERFORM. When error returns we log them in
update_engine.log and send UMA metrics.
When update_engine does not get http response code from libcurl, we log
internal error code of the libcurl transfer for diagnosis.
Chrome CL to add the metrics enum is here: https://chromium-review.googlesource.com/c/chromium/src/+/1566150
BUG=chromium:927039
TEST=unittest
Change-Id: Ie8ce9dc0a6ce5ff6ffc2ff9425b652d125518558
Reviewed-on: https://chromium-review.googlesource.com/1562172
Commit-Ready: Sean Abraham <seanabraham@chromium.org>
Tested-by: Xiaochu Liu <xiaochu@chromium.org>
Reviewed-by: Xiaochu Liu <xiaochu@chromium.org>
Reviewed-by: Amin Hassani <ahassani@chromium.org>
diff --git a/metrics_constants.h b/metrics_constants.h
index eabb8fb..b3833a3 100644
--- a/metrics_constants.h
+++ b/metrics_constants.h
@@ -60,6 +60,10 @@
// above block and before the kInputMalformed field. This
// is to ensure that error codes are not reordered.
+ // This error is reported when libcurl has an internal error that
+ // update_engine can't recover from.
+ kInternalError = 99,
+
// This error code is used to convey that malformed input was given
// to the utils::GetDownloadErrorCode() function. This should never
// happen but if it does it's because of an internal update_engine