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 kChromeStatsSampleKey[] = L"UsageStatsInSample";

[Alexei Svitkine (slow), 2016/08/12 17:47:48]

How about using a similar variable naming convention as kRegValueUsageStats?

e.g. kRegValueUsageStatsInSample

(Although, I guess this convention isn't constently followed - still I prefer
you at least make it match some existing style rather than adding a whole new
one.)

[jwd, 2016/08/12 20:04:30]

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 159 matching lines @@
       } else {
         Trace(L"Failed to create directory %ls, last error is %d\n",
               full_path_str, error_code);
         return false;
       }
     }
   }
   return true;
 }
 
+std::wstring GetChromeInstallRegistryPath() {
+  std::wstring registry_path = L"Software\\";
+  registry_path += GetChromeInstallSubDirectory();
+  return registry_path;
+}
+
 bool GetCollectStatsConsentImpl(const std::wstring& exe_path) {
   bool enabled = true;
   bool controlled_by_policy = ReportingIsEnforcedByPolicy(&enabled);
 
   if (controlled_by_policy && !enabled)
     return false;
 
   bool system_install = IsSystemInstall(exe_path.c_str());
   std::wstring app_guid;
 
@@ skipping 158 matching lines @@
 }
 
 bool GetCollectStatsConsent() {
   return GetCollectStatsConsentImpl(GetCurrentProcessExePath());
 }
 
 bool GetCollectStatsConsentForTesting(const std::wstring& exe_path) {
   return GetCollectStatsConsentImpl(exe_path);
 }
 
+bool GetCollectStatsInSample() {
+  std::wstring registry_path = GetChromeInstallRegistryPath();
+
+  DWORD out_value = 0;
+  if (!nt::QueryRegValueDWORD(nt::HKCU, registry_path.c_str(),
+                              kChromeStatsSampleKey, &out_value)) {
+    // If reading the value failed, treat it as though sampling isn't in effect,
+    // implicitly meaning this install in in-sample.

[Alexei Svitkine (slow), 2016/08/12 17:47:48]

Nit: "this install in sample" -> "this install is in the sample"

[jwd, 2016/08/12 20:04:30]

Done.

+    return true;
+  }
+  return out_value == 1;
+}
+
+bool SetCollectStatsInSample(bool in_sample) {
+  std::wstring registry_path = GetChromeInstallRegistryPath();
+
+  HANDLE key_handle = INVALID_HANDLE_VALUE;
+  if (!nt::CreateRegKey(nt::HKCU, registry_path.c_str(), KEY_SET_VALUE,
+                        &key_handle)) {
+    nt::CloseRegKey(key_handle);
+    return false;
+  }
+
+  return nt::SetRegValueDWORD(key_handle, kChromeStatsSampleKey,
+                              in_sample ? 1 : 0);
+}
+
 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 246 matching lines @@
   result += kGoogleChromeInstallSubDir2;
   if (IsSxSChrome(GetCurrentProcessExePath().c_str()))
     result += kSxSSuffix;
   return result;
 #else
   return std::wstring(kChromiumInstallSubDir);
 #endif
 }
 
 std::wstring GetBrowserCrashDumpAttemptsRegistryPath() {
-  std::wstring registry_path = L"Software\\";
-  registry_path += GetChromeInstallSubDirectory();
+  std::wstring registry_path = GetChromeInstallRegistryPath();
   registry_path += kBrowserCrashDumpMetricsSubKey;
   return registry_path;
 }
 
 bool MatchPattern(const std::wstring& source, const std::wstring& pattern) {
   assert(pattern.find(L"**") == std::wstring::npos);
   return MatchPatternImpl(source, pattern, 0, 0);
 }
 
 std::string UTF16ToUTF8(const std::wstring& source) {
@@ skipping 156 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