1// Copyright (c) 2009 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef CHROME_BROWSER_PROCESS_INFO_SNAPSHOT_H_
6#define CHROME_BROWSER_PROCESS_INFO_SNAPSHOT_H_
7
8#include <sys/types.h>
9
10#include <map>
11#include <string>
12#include <vector>
13
14#include "base/process/process_handle.h"
15#include "base/process/process_metrics.h"
16
17// A class which captures process information at a given point in time when its
18// |Sample()| method is called. This information can then be probed by PID.
19// |Sample()| may take a while to complete, so if calling from the browser
20// process, only do so from the file thread.
21// TODO(viettrungluu): This is currently only implemented and used on Mac, so
22// things are very Mac-specific. If this is ever implemented for other
23// platforms, we should subclass and add opaqueness (probably |ProcInfoEntry|
24// should be considered opaque).
25class ProcessInfoSnapshot {
26 public:
27  ProcessInfoSnapshot();
28  ~ProcessInfoSnapshot();
29
30  // Maximum size of lists of PIDs which this class will accept; used in
31  // |Sample()| below.
32  static const size_t kMaxPidListSize;
33
34  // Capture a snapshot of process memory information for the
35  // given list of PIDs. Call only from the file thread.
36  //   |pid_list| - list of |ProcessId|s on which to capture information; must
37  //     have no more than |kMaxPidListSize| (above) entries,
38  //   returns - |true| if okay, |false| on error.
39  bool Sample(std::vector<base::ProcessId> pid_list);
40
41  // Reset all statistics (deallocating any memory allocated).
42  void Reset();
43
44  // Our basic structure for storing information about a process (the names are
45  // mostly self-explanatory). Note that |command| may not actually reflect the
46  // actual executable name; never trust it absolutely, and only take it
47  // half-seriously when it begins with '/'.
48  struct ProcInfoEntry {
49    base::ProcessId pid;
50    base::ProcessId ppid;
51    uid_t uid;
52    uid_t euid;
53    // Explicitly use uint64_t instead of size_t in case this code is running
54    // in a 32 bit process and the target process is 64 bit.
55    uint64_t rss;
56    uint64_t rshrd;
57    uint64_t rprvt;
58    uint64_t vsize;
59    std::string command;
60
61    ProcInfoEntry();
62  };
63
64  // Get process information for a given PID.
65  //   |pid| - self-explanatory.
66  //   |proc_info| - place to put the process information.
67  //   returns - |true| if okay, |false| on error (including PID not found).
68  bool GetProcInfo(int pid,
69                   ProcInfoEntry* proc_info) const;
70
71  // Fills a |CommittedKBytes| with both resident and paged memory usage, as per
72  // its definition (or as close as we can manage). In the current (Mac)
73  // implementation, we map:
74  //                              vsize --> comm_priv,
75  //                                  0 --> comm_mapped,
76  //                                  0 --> comm_image;
77  //   in about:memory: virtual:private  =  comm_priv,
78  //                     virtual:mapped  =  comm_mapped.
79  // TODO(viettrungluu): Doing such a mapping is kind of ugly.
80  //   |pid| - self-explanatory.
81  //   |usage| - pointer to |CommittedBytes| to fill; zero-ed on error.
82  //   returns - |true| on success, |false| on error (including PID not found).
83  bool GetCommittedKBytesOfPID(int pid,
84                               base::CommittedKBytes* usage) const;
85
86  // Fills a |WorkingSetKBytes| containing resident private and shared memory,
87  // as per its definition (or as close as we can manage). In the current (Mac)
88  // implementation, we map:
89  //                          rprvt --> ws_priv,
90  //                            rss --> ws_shareable,
91  //                          rshrd --> ws_shared;
92  //   in about:memory: res:private  =  ws_priv + ws_shareable - ws_shared,
93  //                     res:shared  =  ws_shared / num_procs,
94  //                      res:total  =  res:private + res:shared.
95  // TODO(viettrungluu): Doing such a mapping is kind of ugly.
96  //   |pid| - self-explanatory.
97  //   |ws_usage| - pointer to |WorkingSetKBytes| to fill; zero-ed on error.
98  //   returns - |true| on success, |false| on error (including PID not found).
99  bool GetWorkingSetKBytesOfPID(int pid,
100                                base::WorkingSetKBytes* ws_usage) const;
101
102  // TODO(viettrungluu): Maybe we should also have the following (again, for
103  // "compatibility"):
104  //    size_t GetWorkingSetSizeOfPID(int pid) const;
105  //    size_t GetPeakWorkingSetSizeOfPID(int pid) const;
106  //    size_t GetPrivateBytesOfPID(int pid) const;
107
108 private:
109  // map from |int| (PID) to |ProcInfoEntry|
110  std::map<int,ProcInfoEntry> proc_info_entries_;
111};
112
113#endif  // CHROME_BROWSER_PROCESS_INFO_SNAPSHOT_H_
114