1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/xpcom/ds/TimeStamp.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,88 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim:set ts=2 sw=2 sts=2 et cindent: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +/*
1.11 + * Implementation of the OS-independent methods of the TimeStamp class
1.12 + */
1.13 +
1.14 +#include "mozilla/TimeStamp.h"
1.15 +#include "prenv.h"
1.16 +
1.17 +namespace mozilla {
1.18 +
1.19 +/**
1.20 + * Wrapper class used to initialize static data used by the TimeStamp class
1.21 + */
1.22 +struct TimeStampInitialization {
1.23 + /**
1.24 + * First timestamp taken when the class static initializers are run. This
1.25 + * timestamp is used to sanitize timestamps coming from different sources.
1.26 + */
1.27 + TimeStamp mFirstTimeStamp;
1.28 +
1.29 + /**
1.30 + * Timestamp representing the time when the process was created. This field
1.31 + * is populated lazily the first time this information is required and is
1.32 + * replaced every time the process is restarted.
1.33 + */
1.34 + TimeStamp mProcessCreation;
1.35 +
1.36 + TimeStampInitialization() {
1.37 + TimeStamp::Startup();
1.38 + mFirstTimeStamp = TimeStamp::Now();
1.39 + };
1.40 +
1.41 + ~TimeStampInitialization() {
1.42 + TimeStamp::Shutdown();
1.43 + };
1.44 +};
1.45 +
1.46 +static TimeStampInitialization sInitOnce;
1.47 +
1.48 +TimeStamp
1.49 +TimeStamp::ProcessCreation(bool& aIsInconsistent)
1.50 +{
1.51 + aIsInconsistent = false;
1.52 +
1.53 + if (sInitOnce.mProcessCreation.IsNull()) {
1.54 + char *mozAppRestart = PR_GetEnv("MOZ_APP_RESTART");
1.55 + TimeStamp ts;
1.56 +
1.57 + /* When calling PR_SetEnv() with an empty value the existing variable may
1.58 + * be unset or set to the empty string depending on the underlying platform
1.59 + * thus we have to check if the variable is present and not empty. */
1.60 + if (mozAppRestart && (strcmp(mozAppRestart, "") != 0)) {
1.61 + /* Firefox was restarted, use the first time-stamp we've taken as the new
1.62 + * process startup time. */
1.63 + ts = sInitOnce.mFirstTimeStamp;
1.64 + } else {
1.65 + TimeStamp now = Now();
1.66 + uint64_t uptime = ComputeProcessUptime();
1.67 +
1.68 + ts = now - TimeDuration::FromMicroseconds(uptime);
1.69 +
1.70 + if ((ts > sInitOnce.mFirstTimeStamp) || (uptime == 0)) {
1.71 + /* If the process creation timestamp was inconsistent replace it with
1.72 + * the first one instead and notify that a telemetry error was
1.73 + * detected. */
1.74 + aIsInconsistent = true;
1.75 + ts = sInitOnce.mFirstTimeStamp;
1.76 + }
1.77 + }
1.78 +
1.79 + sInitOnce.mProcessCreation = ts;
1.80 + }
1.81 +
1.82 + return sInitOnce.mProcessCreation;
1.83 +}
1.84 +
1.85 +void
1.86 +TimeStamp::RecordProcessRestart()
1.87 +{
1.88 + sInitOnce.mProcessCreation = TimeStamp();
1.89 +}
1.90 +
1.91 +} // namespace mozilla
