Adding support for sampling crashes in Chrome on Windows.

chrome/install_static/install_util.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/install_static/install_util.h"
 
 #include <windows.h>
 #include <assert.h>
 #include <algorithm>
 #include <iostream>
@@ skipping 37 matching lines @@
 const wchar_t kRegValueUsageStats[] = L"usagestats";
 const wchar_t kUninstallArgumentsField[] = L"UninstallArguments";
 const wchar_t kMetricsReportingEnabled[] = L"MetricsReportingEnabled";
 
 const wchar_t kAppGuidCanary[] = L"{4ea16ac7-fd5a-47c3-875b-dbf4a2008c20}";
 const wchar_t kAppGuidGoogleChrome[] =
     L"{8A69D345-D564-463c-AFF1-A69D9E530F96}";
 const wchar_t kAppGuidGoogleBinaries[] =
     L"{4DC8B4CA-1BDA-483e-B5FA-D3C12E15B62D}";
 
+const wchar_t kChromeMetrics[] = L"\\MetricsReporting";

[Alexei Svitkine (slow), 2016/08/10 21:49:33]

Are just using this for the one sub-key? Seems strange given that usagestats
above isn't under this.

I would just put the key below next to usagestats and not have the intermediate
dir. Unless there's a good reason for this grouping?

[jwd, 2016/08/11 21:41:02]

Done.

+const wchar_t kChromeStatsSampleKey[] = L"usagestatsinsample";

[Alexei Svitkine (slow), 2016/08/10 21:49:33]

I know there's no comments here currently, but please add some about this to
explain what this means and what possible values it can have. Or in the header
file I guess.

[jwd, 2016/08/11 21:41:02]

Done.

+
 const wchar_t kHeadless[] = L"CHROME_HEADLESS";
 const wchar_t kShowRestart[] = L"CHROME_CRASHED";
 const wchar_t kRestartInfo[] = L"CHROME_RESTART";
 const wchar_t kRtlLocale[] = L"RIGHT_TO_LEFT";
 
 const char kGpuProcess[] = "gpu-process";
 const char kPpapiPluginProcess[] = "ppapi";
 const char kRendererProcess[] = "renderer";
 const char kUtilityProcess[] = "utility";
 const char kProcessType[] = "type";
@@ skipping 196 matching lines @@
   // Second, try kRegPathClientState.
   full_key_path = kRegPathClientState;
   full_key_path.append(1, L'\\');
   full_key_path.append(app_guid);
   return (nt::QueryRegValueDWORD((system_install ? nt::HKLM : nt::HKCU),
                                  full_key_path.c_str(), kRegValueUsageStats,
                                  &out_value) &&
           out_value == 1);
 }
 
+bool GetCollectStatsInSampleImpl(const std::wstring& exe_path) {
+  std::wstring registry_path = L"Software\\";

[Alexei Svitkine (slow), 2016/08/10 21:49:33]

Seems strange to have this hardcoded. Can this be a constant? Or maybe a
function that returns the chrome install registry path so each function doesn't
need to append it themselves.

[jwd, 2016/08/11 21:41:02]

Done.

+  registry_path += GetChromeInstallSubDirectory();
+  registry_path += kChromeMetrics;
+
+  DWORD out_value = 0;
+  return (nt::QueryRegValueDWORD(nt::HKCU, registry_path.c_str(),
+                                 kChromeStatsSampleKey, &out_value) &&
+          out_value == 1);

[Alexei Svitkine (slow), 2016/08/10 21:49:33]

What happens if the registry key isn't set? Would this return "not in sample" -
which seems not correct.

[jwd, 2016/08/11 21:41:02]

Done.

+}
+
 // Returns true if the |source| string matches the |pattern|. The pattern
 // may contain wildcards like '?' which matches one character or a '*'
 // which matches 0 or more characters.
 // Please note that pattern matches the whole string. If you want to find
 // something in the middle of the string then you need to specify the pattern
 // as '*xyz*'.
 // |source_index| is the index of the current character being matched in
 // |source|.
 // |pattern_index| is the index of the current pattern character in |pattern|
 // which is matched with source.
@@ skipping 121 matching lines @@
 }
 
 bool GetCollectStatsConsent() {
   return GetCollectStatsConsentImpl(GetCurrentProcessExePath());
 }
 
 bool GetCollectStatsConsentForTesting(const std::wstring& exe_path) {
   return GetCollectStatsConsentImpl(exe_path);
 }
 
+bool GetCollectStatsInSample() {
+  return GetCollectStatsInSampleImpl(GetCurrentProcessExePath());
+}
+
 bool ReportingIsEnforcedByPolicy(bool* metrics_is_enforced_by_policy) {
   DWORD value = 0;
 
   // First, try HKLM.
   if (nt::QueryRegValueDWORD(nt::HKLM, kRegPathChromePolicy,
                              kMetricsReportingEnabled, &value)) {
     *metrics_is_enforced_by_policy = (value != 0);
     return true;
   }
 
@@ skipping 424 matching lines @@
     switch_value_end_offset = command_line_copy.length();
 
   std::string switch_value = command_line_copy.substr(
       switch_value_start_offset,
       switch_value_end_offset - (switch_offset + switch_token.length()));
   TrimT<std::string>(&switch_value);
   return switch_value;
 }
 
 }  // namespace install_static