summaryrefslogtreecommitdiffstats
path: root/toolkit/components/glean/bindings/private/Timespan.h
blob: 6425c03046ee561a008dda3d827d96912a7e6316 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_glean_GleanTimespan_h
#define mozilla_glean_GleanTimespan_h

#include "mozilla/Maybe.h"
#include "nsIGleanMetrics.h"
#include "mozilla/glean/fog_ffi_generated.h"

namespace mozilla::glean {

namespace impl {

class TimespanMetric {
 public:
  constexpr explicit TimespanMetric(uint32_t aId) : mId(aId) {}

  /**
   * Start tracking time for the provided metric.
   *
   * This records an error if it’s already tracking time (i.e. start was already
   * called with no corresponding [stop]): in that case the original
   * start time will be preserved.
   */
  void Start() const { fog_timespan_start(mId); }

  /**
   * Stop tracking time for the provided metric.
   *
   * Sets the metric to the elapsed time, but does not overwrite an already
   * existing value.
   * This will record an error if no [start] was called or there is an already
   * existing value.
   */
  void Stop() const { fog_timespan_stop(mId); }

  /**
   * **Test-only API**
   *
   * Gets the currently stored value as an integer.
   *
   * This function will attempt to await the last parent-process task (if any)
   * writing to the the metric's storage engine before returning a value.
   * This function will not wait for data from child processes.
   *
   * This doesn't clear the stored value.
   * Parent process only. Panics in child processes.
   *
   * @param aPingName The (optional) name of the ping to retrieve the metric
   *        for. Defaults to the first value in `send_in_pings`.
   *
   * @return value of the stored metric, or Nothing() if there is no value.
   */
  Maybe<int64_t> TestGetValue(const nsACString& aPingName = nsCString()) const {
    if (!fog_timespan_test_has_value(mId, &aPingName)) {
      return Nothing();
    }
    return Some(fog_timespan_test_get_value(mId, &aPingName));
  }

 private:
  const uint32_t mId;
};
}  // namespace impl

class GleanTimespan final : public nsIGleanTimespan {
 public:
  NS_DECL_ISUPPORTS
  NS_DECL_NSIGLEANTIMESPAN

  explicit GleanTimespan(uint32_t aId) : mTimespan(aId){};

 private:
  virtual ~GleanTimespan() = default;

  const impl::TimespanMetric mTimespan;
};

}  // namespace mozilla::glean

#endif /* mozilla_glean_GleanTimespan_h */