Remove dependencies on chrome\installer from the ChromeCrashReporterClient class on Windows.

chrome/install_static/install_util.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.

[grt (UTC plus 2), 2016/04/29 20:50:56]

please add an OWNERS file to this dir with at least me and gab in it. i had no
idea this existed!

[ananta, 2016/04/29 22:49:24]

Done. Added robertshield too. This file went in last week.

 // 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 <assert.h>
+#include <memory>
 #include <windows.h>

[grt (UTC plus 2), 2016/04/29 20:50:56]

https://google.github.io/styleguide/cppguide.html#Names_and_Order_of_Includes:

#include <windows.h>  (special treatment because this usually must precede other
WinSDK headers)
#include <assert.h>
#include <memory>

[ananta, 2016/04/29 22:49:24]

Done.

-#include <stddef.h>
 
 #include "base/macros.h"

[grt (UTC plus 2), 2016/04/29 20:50:56]

would a DEPS file in this directory help prevent accidental inclusion of other
things?

[ananta, 2016/04/29 22:49:23]

Thanks. Good point. Done

-#include "base/strings/string16.h"
+#include "build/build_config.h"
+
+namespace install_static {
 
 ProcessType g_process_type = ProcessType::UNINITIALIZED;
 
+// Chrome channel display names.
+// TODO(ananta)
+// http://crbug.com/604923
+// These constants are defined in the chrome/installer directory as well. We
+// need to unify them.
+const wchar_t kChromeChannelUnknown[] = L"unknown";
+const wchar_t kChromeChannelCanary[] = L"canary";
+const wchar_t kChromeChannelDev[] = L"dev";
+const wchar_t kChromeChannelBeta[] = L"beta";
+const wchar_t kChromeChannelStable[] = L"";
+const wchar_t kChromeChannelStableExplicit[] = L"stable";
+
 namespace {
 
 const wchar_t kRegPathClientState[] = L"Software\\Google\\Update\\ClientState";

[grt (UTC plus 2), 2016/04/29 20:50:56]

this is only for GOOGLE_CHROME_BUILD. Chromium builds use "Software\\Chromium"
for Clients, ClientState, and ClientStateMedium.

[ananta, 2016/04/29 22:49:23]

Done.

[ananta, 2016/04/29 22:49:24]

Done.

 const wchar_t kRegPathClientStateMedium[] =
     L"Software\\Google\\Update\\ClientStateMedium";
 #if defined(GOOGLE_CHROME_BUILD)
 const wchar_t kRegPathChromePolicy[] = L"SOFTWARE\\Policies\\Google\\Chrome";
 #else
 const wchar_t kRegPathChromePolicy[] = L"SOFTWARE\\Policies\\Chromium";
 #endif  // defined(GOOGLE_CHROME_BUILD)
 
 const wchar_t kRegValueUsageStats[] = L"usagestats";
 const wchar_t kUninstallArgumentsField[] = L"UninstallArguments";
 const wchar_t kMetricsReportingEnabled[] = L"MetricsReportingEnabled";
 
+const wchar_t kRegPathGoogleUpdate[] = L"Software\\Google\\Update";
+const wchar_t kRegGoogleUpdateVersion[] = L"version";
+
 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}";
 
+// TODO(ananta)
+// http://crbug.com/604923
+// These constants are defined in the chrome/installer directory as well. We
+// need to unify them.
+#if defined(GOOGLE_CHROME_BUILD)
+const wchar_t kSxSSuffix[] = L" SxS";
+const wchar_t kGoogleChromeInstallSubDir1[] = L"Google";
+const wchar_t kGoogleChromeInstallSubDir2[] = L"Chrome";
+const wchar_t kRegApField[] = L"ap";
+#else
+const wchar_t kChromiumInstallSubDir[] = L"Chromium";
+#endif
+const wchar_t kUserDataDirname[] = L"User Data";
+const wchar_t kBrowserCrashDumpMetricsSubKey[] = L"\\BrowserCrashDumpAttempts";
+
+void Trace(const wchar_t* format_string, ...) {
+  static const int kMaxLogBufferSize = 1024;
+  static wchar_t buffer[kMaxLogBufferSize] = {};
+
+  va_list args = {};
+
+  va_start(args, format_string);
+  vswprintf(buffer, arraysize(buffer), format_string, args);
+  OutputDebugString(buffer);
+  va_end(args);
+}
+
 bool ReadKeyValueString(bool system_install, const wchar_t* key_path,
                         const wchar_t* guid, const wchar_t* value_to_read,
                         base::string16* value_out) {
   HKEY key = NULL;
   value_out->clear();
 
   base::string16 full_key_path(key_path);
-  full_key_path.append(1, L'\\');
-  full_key_path.append(guid);
+  if (wcslen(guid) > 0) {

[grt (UTC plus 2), 2016/04/29 20:50:56]

  if (guid && *guid) {

[ananta, 2016/04/29 22:49:23]

Done.

[ananta, 2016/04/29 22:49:24]

Done.

+    full_key_path.append(1, L'\\');
+    full_key_path.append(guid);
+  }
 
   if (::RegOpenKeyEx(system_install ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER,
                      full_key_path.c_str(), 0,
                      KEY_QUERY_VALUE | KEY_WOW64_32KEY, &key) !=

[grt (UTC plus 2), 2016/04/29 20:50:55]

please note in a comment for this fn and the DW variant below that it only looks
in the 32-bit view of the registry.

[ananta, 2016/04/29 22:49:23]

Done.

[ananta, 2016/04/29 22:49:24]

Done.

                      ERROR_SUCCESS) {
     return false;
   }
 
   const size_t kMaxStringLength = 1024;
   wchar_t raw_value[kMaxStringLength] = {};
   DWORD size = sizeof(raw_value);
   DWORD type = REG_SZ;
   LONG result = ::RegQueryValueEx(key, value_to_read, 0, &type,
                                   reinterpret_cast<LPBYTE>(raw_value), &size);
@@ skipping 39 matching lines @@
   DWORD size = sizeof(*value_out);
   DWORD type = REG_DWORD;
   LONG result = ::RegQueryValueEx(key, value_to_read, 0, &type,
                                   reinterpret_cast<BYTE*>(value_out), &size);
 
   ::RegCloseKey(key);
 
   return result == ERROR_SUCCESS && size == sizeof(*value_out);
 }
 
+struct LanguageAndCodePage {

[grt (UTC plus 2), 2016/04/29 20:50:56]

nit: move this into GetLanguageAndCodePageFromVersionResource

[ananta, 2016/04/29 22:49:23]

Done.

+  WORD language;
+  WORD code_page;
+};
+
+bool GetLanguageAndCodePageFromVersionResource(const char* version_resource,
+                                               WORD* language,
+                                               WORD* code_page) {
+  if (!version_resource)
+    return false;
+
+  LanguageAndCodePage* translation_info = nullptr;

[grt (UTC plus 2), 2016/04/29 20:50:56]

MSDN leads me to believe that this should be:
  DWORD *translation_info = nullptr;
  ...
  *language = LOWORD(*translation_info);
  *code_page = HIWORD(*translation_info);
(from
https://msdn.microsoft.com/en-us/library/windows/desktop/ms646994(v=vs.85).aspx)

[ananta, 2016/04/29 22:49:23]

This is based on
https://msdn.microsoft.com/en-us/library/windows/desktop/ms647464(v=vs.85).aspx.
The helper in base also does the same thing.

[grt (UTC plus 2), 2016/05/02 22:22:06]

Okay, thanks for the pointer.

+  uint32_t page_count = 0;

[grt (UTC plus 2), 2016/04/29 20:50:56]

"count" is a bit of a misnomer since this is populated with a size in bytes
rather than a count of something useful.

[ananta, 2016/04/29 22:49:23]

Renamed to data_size_in_bytes

+  BOOL query_result = VerQueryValue(version_resource,
+                                    L"\\VarFileInfo\\Translation",
+                                    reinterpret_cast<void**>(&translation_info),
+                                    &page_count);
+  if (!query_result)
+    return false;
+
+  *language = translation_info->language;
+  *code_page = translation_info->code_page;
+  return true;
+}
+
+bool GetValueFromVersionResource(const char* version_resource,
+                                 const base::string16& name,
+                                 base::string16* value_str) {
+  assert(value_str);
+  value_str->clear();
+
+  WORD language = 0;
+  WORD code_page = 0;
+  if (!GetLanguageAndCodePageFromVersionResource(version_resource,
+                                                 &language,
+                                                 &code_page)) {
+    return false;

[grt (UTC plus 2), 2016/04/29 20:50:56]

based on
https://msdn.microsoft.com/en-us/library/windows/desktop/ms646994(v=vs.85).aspx,
should we continue trying to get values under the assumption that they're "both
language and code page independent"? maybe simplify things and use (0,0) in the
loop below in this case. seems a bit more robust.

[ananta, 2016/04/29 22:49:24]

We could possibly do that. The logic below is the same as base. I am wary of
changing it for now. Don't want this to cause regressions.

[grt (UTC plus 2), 2016/05/02 22:22:06]

Gotcha. Thinking about it more, why are we even doing these random
shots-in-the-dark? Does the call to VerQueryValue in
GetLanguageAndCodePageFromVersionResource return the exact array of lang/CP
pairs that are present in the file? Should we really iterate over all of those?
Don't bother changing it now, but consider this a note for the future.

[ananta, 2016/05/02 22:43:27]

Added a TODO in the function. Will look into this in a subsequent patch

+  }
+
+  WORD lang_codepage[8] = {};
+  size_t i = 0;
+  // Use the language and codepage
+  lang_codepage[i++] = language;
+  lang_codepage[i++] = code_page;
+  // Use the default language and codepage from the resource.
+  lang_codepage[i++] = ::GetUserDefaultLangID();
+  lang_codepage[i++] = code_page;
+  // Use the language from the resource and Latin codepage (most common).
+  lang_codepage[i++] = language;
+  lang_codepage[i++] = 1252;
+  // Use the default language and Latin codepage (most common).
+  lang_codepage[i++] = ::GetUserDefaultLangID();
+  lang_codepage[i++] = 1252;
+
+  static_assert((arraysize(lang_codepage) % 2) == 0,
+                "Language code page size should be a multiple of 2");
+  assert(arraysize(lang_codepage) == i);
+
+  i = 0;

[grt (UTC plus 2), 2016/04/29 20:50:56]

call me crazy, but:
  for (i = 0; i < arraysize(lang_codepage); ) {

[ananta, 2016/04/29 22:49:24]

Done.

+  while (i < arraysize(lang_codepage)) {
+    wchar_t sub_block[MAX_PATH] = {};

[grt (UTC plus 2), 2016/04/29 20:50:56]

we don't really need to zero this out since it gets overwritten by _snwprintf_s

[ananta, 2016/04/29 22:49:23]

Done.

+    WORD language = lang_codepage[i++];
+    WORD code_page = lang_codepage[i++];
+    _snwprintf_s(sub_block, MAX_PATH, MAX_PATH,
+        L"\\StringFileInfo\\%04x%04x\\%ls", language, code_page, name.c_str());

[grt (UTC plus 2), 2016/04/29 20:50:55]

WORD is an unsigned short, so %04hx

[ananta, 2016/04/29 22:49:23]

Done.
https://msdn.microsoft.com/en-us/library/windows/desktop/ms647464(v=vs.85).aspx
uses %04x though

+    void* value = nullptr;
+    uint32_t size = 0;
+    BOOL r = ::VerQueryValue(version_resource, sub_block, &value, &size);
+    if (r && value) {
+      value_str->assign(static_cast<wchar_t*>(value));
+      return true;
+    }
+  }
+  return false;
+}
+
+// Returns the executable path for the current process.
+base::string16 GetCurrentProcessExePath() {
+  wchar_t exe_path[MAX_PATH] = {};

[grt (UTC plus 2), 2016/04/29 20:50:55]

is zeroing needed?

[ananta, 2016/04/29 22:49:23]

I tend to always do it. Removed.

+  if (GetModuleFileName(NULL, exe_path, arraysize(exe_path)) == 0)

[grt (UTC plus 2), 2016/04/29 20:50:56]

nullptr

[ananta, 2016/04/29 22:49:24]

Done.

+    return base::string16();
+  return exe_path;
+}
+
+// UTF8 to UTF16 and vice versa conversion helpers. We cannot use the base
+// string conversion utilities here as they bring about a dependency on
+// user32.dll which is not allowed in this file.
+
+// Convert a UTF16 string to an UTF8 string.
+std::string utf16_to_utf8(const base::string16 &source) {
+  if (source.empty())
+    return std::string();
+  int size = ::WideCharToMultiByte(CP_UTF8, 0, &source[0],
+      static_cast<int>(source.size()), nullptr, 0, nullptr, nullptr);
+  std::string result(size, 0);
+  if (::WideCharToMultiByte(CP_UTF8, 0, &source[0],
+          static_cast<int>(source.size()), &result[0], size, nullptr,
+          nullptr) != size) {
+    assert(false);
+    return std::string();
+  }
+  return result;
+}
+
+// Convert a UTF8 string to a UTF16 string.
+base::string16 utf8_to_string16(const std::string &source) {
+  if (source.empty())
+    return base::string16();
+  int size = ::MultiByteToWideChar(CP_UTF8, 0, &source[0],
+      static_cast<int>(source.size()), nullptr, 0);
+  base::string16 result(size, 0);

[grt (UTC plus 2), 2016/04/29 20:50:56]

uber-nit: 0 -> L'\0' to make it super clear that the 2nd arg is a character
value.

[ananta, 2016/04/29 22:49:24]

Done.

[grt (UTC plus 2), 2016/05/02 22:22:06]

Hah, you did it on the line above that I missed, but not here. ;-)

[ananta, 2016/05/02 22:43:27]

Sorry, fixed.

+  if (::MultiByteToWideChar(CP_UTF8, 0, &source[0],
+          static_cast<int>(source.size()), &result[0], size) != size) {
+    assert(false);
+    return base::string16();
+  }
+  return result;
+}
+
+bool RecursiveDirectoryCreate(const base::string16& full_path) {
+  // If the path exists, we've succeeded if it's a directory, failed otherwise.
+  const wchar_t* full_path_str = full_path.c_str();
+  DWORD file_attributes = ::GetFileAttributes(full_path_str);
+  if (file_attributes != INVALID_FILE_ATTRIBUTES) {
+    if ((file_attributes & FILE_ATTRIBUTE_DIRECTORY) != 0) {
+      Trace(L"%hs( %ls directory exists )\n", __FUNCTION__, full_path_str);
+      return true;
+    }
+    Trace(L"%hs( %ls directory conflicts with an existing file. )\n",
+          __FUNCTION__, full_path_str);
+    return false;
+  }
+
+  // Invariant:  Path does not exist as file or directory.
+
+  // Attempt to create the parent recursively.  This will immediately return
+  // true if it already exists, otherwise will create all required parent
+  // directories starting with the highest-level missing parent.
+  base::string16 parent_path;
+  std::size_t pos = full_path.find_last_of(L"/\\");
+  if (pos != base::string16::npos) {
+    parent_path = full_path.substr(0, pos);
+    if (!RecursiveDirectoryCreate(parent_path)) {
+      Trace(L"Failed to create one of the parent directories");
+      return false;
+    }
+  }
+  if (!::CreateDirectory(full_path_str, NULL)) {
+    DWORD error_code = ::GetLastError();
+    if (error_code == ERROR_ALREADY_EXISTS) {
+      DWORD file_attributes = GetFileAttributes(full_path_str);
+      if ((file_attributes != INVALID_FILE_ATTRIBUTES) &&
+          ((file_attributes & FILE_ATTRIBUTE_DIRECTORY) != 0)) {
+        // This error code ERROR_ALREADY_EXISTS doesn't indicate whether we
+        // were racing with someone creating the same directory, or a file
+        // with the same path.  If the directory exists, we lost the
+        // race to create the same directory.
+        return true;
+      } else {
+        Trace(L"Failed to create directory %ls, last error is %d\n",
+              full_path_str, error_code);
+        return false;
+      }
+    }
+  }
+  return true;
+}
+
+bool GetCollectStatsConsentImpl(const base::string16& exe_path) {
+  bool enabled = true;
+  bool controlled_by_policy = ReportingIsEnforcedByPolicy(&enabled);
+
+  if (controlled_by_policy && !enabled)

[grt (UTC plus 2), 2016/04/29 20:50:56]

i think the right thing here is really:
  if (ReportingIsEnforcedByPolicy(&enabled))
    return enabled;

this is consistent with "mandatory" policies, which cannot be overridden by the
user. the current logic allows an admin to force consent off, but not to force
it on, which doesn't seem correct.

[ananta, 2016/04/29 22:49:24]

Done.

+    return false;
+
+  bool system_install = IsSystemInstall(exe_path.c_str());
+  base::string16 app_guid;
+
+  if (IsCanary(exe_path.c_str())) {
+    app_guid = kAppGuidCanary;
+  } else {
+    app_guid = IsMultiInstall(system_install) ? kAppGuidGoogleBinaries :
+        kAppGuidGoogleChrome;
+  }
+
+  DWORD out_value = 0;
+  if (system_install &&
+    ReadKeyValueDW(system_install, kRegPathClientStateMedium, app_guid,

[grt (UTC plus 2), 2016/04/29 20:50:55]

nit: indentation. please use "git cl format".

[ananta, 2016/04/29 22:49:24]

Done.

+        kRegValueUsageStats, &out_value)) {
+    return out_value == 1;
+  }
+
+  return ReadKeyValueDW(system_install, kRegPathClientState, app_guid,
+      kRegValueUsageStats, &out_value) && out_value == 1;
+}
+
+// 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.
+bool MatchPatternImpl(const base::string16& source,
+                      const base::string16& pattern,
+                      size_t source_index,
+                      size_t pattern_index) {
+  if (source.empty() && pattern.empty())
+    return true;
+
+  if (source_index > source.length() || pattern_index > pattern.length())
+    return false;
+
+  // If we reached the end of both strings, then we are done.
+  if ((source_index == source.length()) &&
+      (pattern_index == pattern.length())) {
+    return true;
+  }
+
+  // If the current character in the pattern is a '*' then make sure that
+  // characters after the pattern are present in the source string. This
+  // assumes that you won't have two consecutive '*' characters in the pattern.
+  if ((pattern[pattern_index] == L'*') &&
+      (pattern_index + 1 < pattern.length()) &&
+      (source_index >= source.length())) {
+    return false;
+  }
+
+  // If the pattern contains wildcard characters '?' or '.' or there is a match
+  // then move ahead in both strings.
+  if ((pattern[pattern_index] == L'?') ||
+      (pattern[pattern_index] == source[source_index])) {
+    return MatchPatternImpl(source, pattern, source_index + 1,
+                            pattern_index + 1);
+  }
+
+  // If we have a '*' then there are two possibilities
+  // 1. We consider current character of source.
+  // 2. We ignore current character of source.
+  if (pattern[pattern_index] == L'*') {
+    return MatchPatternImpl(source, pattern, source_index + 1,
+                            pattern_index) ||
+           MatchPatternImpl(source, pattern, source_index, pattern_index + 1);
+  }
+  return false;
+}
+
 }  // namespace
 
 bool IsCanary(const wchar_t* exe_path) {

[grt (UTC plus 2), 2016/04/29 20:50:56]

is it possible/does it make sense to use base::StringPiece16 rather than raw
pointers for these fns?

[ananta, 2016/04/29 22:49:24]

Sadly no. StringPiece16 comes with logging.h, which causes all kinds of problems
in chrome_elf

[grt (UTC plus 2), 2016/05/02 22:22:06]

Acknowledged.

   return wcsstr(exe_path, L"Chrome SxS\\Application") != NULL;
 }
 
 bool IsSystemInstall(const wchar_t* exe_path) {
   wchar_t program_dir[MAX_PATH] = {};
   DWORD ret = ::GetEnvironmentVariable(L"PROGRAMFILES", program_dir,
                                        arraysize(program_dir));
   if (ret && ret < MAX_PATH && !wcsncmp(exe_path, program_dir, ret))

[grt (UTC plus 2), 2016/04/29 20:50:56]

wdyt of _wcsnicmp for path comparisons? i think we generally try to use
FilePath::CompareEqualIgnoreCase on winderz.

[grt (UTC plus 2), 2016/04/29 20:50:56]

nit: i prefer arraysize(program_dir) over MAX_PATH so that this line doesn't
need to be updated if someone ever decides to bump the size of the array.

[ananta, 2016/04/29 22:49:23]

Yeah. Done.

[ananta, 2016/04/29 22:49:24]

Done.

     return true;
 
   ret = ::GetEnvironmentVariable(L"PROGRAMFILES(X86)", program_dir,
                                  arraysize(program_dir));
   if (ret && ret < MAX_PATH && !wcsncmp(exe_path, program_dir, ret))
     return true;
 
   return false;
 }
 
 bool IsMultiInstall(bool is_system_install) {
   base::string16 args;
   if (!ReadKeyValueString(is_system_install, kRegPathClientState,
                           kAppGuidGoogleChrome, kUninstallArgumentsField,
                           &args)) {
     return false;
   }
   return args.find(L"--multi-install") != base::string16::npos;
 }
 
-bool AreUsageStatsEnabled(const wchar_t* exe_path) {
-  bool enabled = true;
-  bool controlled_by_policy = ReportingIsEnforcedByPolicy(&enabled);
+bool GetCollectStatsConsent() {
+  return GetCollectStatsConsentImpl(GetCurrentProcessExePath());
+}
 
-  if (controlled_by_policy && !enabled)
-    return false;
-
-  bool system_install = IsSystemInstall(exe_path);
-  base::string16 app_guid;
-
-  if (IsCanary(exe_path)) {
-    app_guid = kAppGuidCanary;
-  } else {
-    app_guid = IsMultiInstall(system_install) ? kAppGuidGoogleBinaries :
-                                                kAppGuidGoogleChrome;
-  }
-
-  DWORD out_value = 0;
-  if (system_install &&
-      ReadKeyValueDW(system_install, kRegPathClientStateMedium, app_guid,
-                     kRegValueUsageStats, &out_value)) {
-    return out_value == 1;
-  }
-
-  return ReadKeyValueDW(system_install, kRegPathClientState, app_guid,
-                        kRegValueUsageStats, &out_value) && out_value == 1;
+bool GetCollectStatsConsentForTesting(const base::string16& exe_path) {
+  return GetCollectStatsConsentImpl(exe_path);
 }
 
 bool ReportingIsEnforcedByPolicy(bool* breakpad_enabled) {

[grt (UTC plus 2), 2016/04/29 20:50:55]

breakpad_enabled -> metrics_reporting_enabled

[ananta, 2016/04/29 22:49:24]

Done.

   HKEY key = NULL;
   DWORD value = 0;
   BYTE* value_bytes = reinterpret_cast<BYTE*>(&value);
   DWORD size = sizeof(value);
   DWORD type = REG_DWORD;
 
   if (::RegOpenKeyEx(HKEY_LOCAL_MACHINE, kRegPathChromePolicy, 0,
                      KEY_QUERY_VALUE, &key) == ERROR_SUCCESS) {
     if (::RegQueryValueEx(key, kMetricsReportingEnabled, 0, &type,
                           value_bytes, &size) == ERROR_SUCCESS) {
@@ skipping 35 matching lines @@
     return;
   }
 
   g_process_type = ProcessType::BROWSER_PROCESS;
 }
 
 bool IsNonBrowserProcess() {
   assert(g_process_type != ProcessType::UNINITIALIZED);
   return g_process_type == ProcessType::NON_BROWSER_PROCESS;
 }
+
+bool GetDefaultUserDataDirectory(base::string16* result) {
+  static const wchar_t kLocalAppData[] = L"%LOCALAPPDATA%";
+
+  std::unique_ptr<wchar_t> user_data_dir_path;
+
+  // This environment variable should be set on Windows 7 and up.
+  // If we fail to find this variable then we default to the temporary files
+  // path.
+  DWORD size = ::ExpandEnvironmentStrings(kLocalAppData, nullptr, 0);
+  if (size) {
+    user_data_dir_path.reset(new wchar_t[size]);
+    if (::ExpandEnvironmentStrings(kLocalAppData,
+                                   user_data_dir_path.get(),
+                                   size) != size) {
+      user_data_dir_path.reset(nullptr);

[grt (UTC plus 2), 2016/04/29 20:50:56]

nit: omit "nullptr"

[ananta, 2016/04/29 22:49:24]

Done.

+    }
+  }
+  // We failed to find the %LOCALAPPDATA% folder. Fallback to the temporary
+  // files path. If we fail to find this we bail.
+  if (!user_data_dir_path.get()) {
+    size = ::GetTempPath(0, nullptr);
+    if (!size)
+      return false;
+    user_data_dir_path.reset(new wchar_t[size + 1]);
+    if (::GetTempPath(size + 1, user_data_dir_path.get()) != size)
+      return false;
+  }
+
+  base::string16 install_sub_directory = GetChromeInstallSubDirectory();
+
+  *result = user_data_dir_path.get();
+  if ((*result)[result->length() - 1] != L'\\')
+    result->append(L"\\");
+  result->append(install_sub_directory);
+  result->append(L"\\");
+  result->append(kUserDataDirname);
+  return true;
+}
+
+bool GetDefaultCrashDumpLocation(base::string16* crash_dir) {
+  // In order to be able to start crash handling very early, we do not rely on
+  // chrome's PathService entries (for DIR_CRASH_DUMPS) being available on
+  // Windows. See https://crbug.com/564398.
+  if (!GetDefaultUserDataDirectory(crash_dir))
+    return false;
+
+  // We have to make sure the user data dir exists on first run. See
+  // http://crbug.com/591504.
+  if (!RecursiveDirectoryCreate(crash_dir->c_str()))
+    return false;
+  crash_dir->append(L"\\Crashpad");
+  return true;
+}
+
+
+std::string GetEnvironmentString(const std::string& variable_name) {
+  DWORD value_length = ::GetEnvironmentVariable(
+      utf8_to_string16(variable_name).c_str(), NULL, 0);
+  if (value_length == 0)
+    return std::string();
+  std::unique_ptr<wchar_t[]> value(new wchar_t[value_length]);
+  ::GetEnvironmentVariable(utf8_to_string16(variable_name).c_str(),
+      value.get(), value_length);
+  return utf16_to_utf8(value.get());
+}
+
+bool SetEnvironmentString(const std::string& variable_name,
+                          const std::string& new_value) {
+  return !!SetEnvironmentVariable(utf8_to_string16(variable_name).c_str(),
+      utf8_to_string16(new_value).c_str());
+}
+
+bool HasEnvironmentVariable(const std::string& variable_name) {
+  return !!::GetEnvironmentVariable(utf8_to_string16(variable_name).c_str(),
+      NULL, 0);
+}
+
+bool GetExecutableVersionDetails(const base::string16& exe_path,
+                                 base::string16* product_name,
+                                 base::string16* version,
+                                 base::string16* special_build,
+                                 base::string16* channel_name) {
+  assert(product_name);
+  assert(version);
+  assert(special_build);
+  assert(channel_name);
+
+  // Default values in case we don't find a version resource.
+  *product_name = L"Chrome";
+  *version = L"0.0.0.0-devel";
+  *channel_name = kChromeChannelUnknown;
+  special_build->clear();
+
+  DWORD dummy = 0;
+  DWORD length = ::GetFileVersionInfoSize(exe_path.c_str(), &dummy);
+  if (length) {
+    std::unique_ptr<char> data(new char[length]);
+    if (::GetFileVersionInfo(exe_path.c_str(), dummy, length,
+                             data.get())) {
+      GetValueFromVersionResource(data.get(), L"ProductVersion", version);
+
+      base::string16 official_build;
+      GetValueFromVersionResource(data.get(), L"Official Build",
+                                  &official_build);
+      if (official_build != L"1")
+        version->append(L"-devel");
+      GetValueFromVersionResource(data.get(), L"ProductShortName",
+                                  product_name);
+      GetValueFromVersionResource(data.get(), L"SpecialBuild", special_build);
+    }
+  }
+  GetChromeChannelName(!IsSystemInstall(exe_path.c_str()), channel_name);
+  return true;
+}
+
+void GetChromeChannelName(bool is_per_user_install,
+                          base::string16* channel_name) {
+#if !defined(GOOGLE_CHROME_BUILD)
+  *channel_name = kChromeChannelUnknown;
+  return;
+#else
+  channel_name->clear();
+  // TODO(ananta)
+  // http://crbug.com/604923
+  // Unify this with the chrome/installer/util/channel_info.h/.cc.
+  if (IsCanary(GetCurrentProcessExePath().c_str())) {
+    *channel_name = L"canary";
+  } else {
+    base::string16 value;
+    if (ReadKeyValueString(!is_per_user_install,
+                           kRegPathClientState,
+                           kAppGuidGoogleChrome,
+                           kRegApField,
+                           &value)) {
+      static const wchar_t kChromeChannelBetaPattern[] = L"1?1-";
+      static const wchar_t kChromeChannelBetaX64Pattern[] = L"*x64-beta*";
+      static const wchar_t kChromeChannelDevPattern[] = L"2?0-d";
+      static const wchar_t kChromeChannelDevX64Pattern[] = L"x64-dev";
+      static const wchar_t kChromeStableMultiInstallPattern[] = L"*multi*";
+
+      std::transform(value.begin(), value.end(), value.begin(), ::tolower);
+
+      // Channel names containing stable should be reported as an empty string.
+      if (value.find(kChromeChannelStableExplicit) !=
+          base::string16::npos) {
+        return;
+      }
+
+      if (MatchPattern(value, kChromeChannelDevPattern) ||
+          MatchPattern(value, kChromeChannelDevX64Pattern)) {
+        channel_name->assign(kChromeChannelDev);
+      }
+
+      if (MatchPattern(value, kChromeChannelBetaPattern) ||
+          MatchPattern(value, kChromeChannelBetaPattern)) {
+        channel_name->assign(kChromeChannelBeta);
+      }
+
+      if (value.find(kChromeStableMultiInstallPattern) !=
+          base::string16::npos) {
+        *channel_name = L"-m";
+      }
+
+      // If we fail to find any matching pattern in the channel name then we
+      // default to empty which means stable. Not sure if this is ok.
+      // TODO(ananta)
+      // http://crbug.com/604923
+      // Check if this is ok.
+    } else {
+      *channel_name = kChromeChannelUnknown;
+    }
+  }
+#endif  // GOOGLE_CHROME_BUILD
+}
+
+std::string GetGoogleUpdateVersion() {
+  base::string16 update_version;
+  if (ReadKeyValueString(IsSystemInstall(GetCurrentProcessExePath().c_str()),
+                         kRegPathGoogleUpdate,
+                         L"",
+                         kRegGoogleUpdateVersion,
+                         &update_version)) {
+    return utf16_to_utf8(update_version);
+  }
+  return std::string();
+}
+
+base::string16 GetChromeInstallSubDirectory() {
+  base::string16 result;
+#if defined(GOOGLE_CHROME_BUILD)
+  base::string16 sub_directory = kGoogleChromeInstallSubDir1;
+  sub_directory += L"\\";
+  sub_directory += kGoogleChromeInstallSubDir2;
+  if (IsCanary(GetCurrentProcessExePath().c_str()))
+    sub_directory += kSxSSuffix;
+  result.append(sub_directory);

[grt (UTC plus 2), 2016/04/29 20:50:56]

nit:
  return result.append(sub_directory);
#else
  return base::string16(kChromiumInstallSubDir);
#endif
}

[ananta, 2016/04/29 22:49:24]

Done.

+#else
+  result = result.append(kChromiumInstallSubDir);
+#endif
+  return result;
+}
+
+base::string16 GetBrowserCrashDumpAttemptsRegistryPath() {
+  base::string16 registry_path = L"Software";

[grt (UTC plus 2), 2016/04/29 20:50:56]

? "Software\\" ?

[ananta, 2016/04/29 22:49:23]

Thanks. Done.

+  base::string16 install_sub_directory = GetChromeInstallSubDirectory();

[grt (UTC plus 2), 2016/04/29 20:50:56]

nit: remove this variable and inline the call to GetChromeInstallSubDirectory
below

[ananta, 2016/04/29 22:49:23]

Done.

+  registry_path += install_sub_directory;
+  registry_path += kBrowserCrashDumpMetricsSubKey;
+  return registry_path;
+}
+
+bool MatchPattern(const base::string16& source,
+                  const base::string16& pattern) {
+  assert(pattern.find(L"**") == base::string16::npos);
+  return MatchPatternImpl(source, pattern, 0, 0);
+}
+
+}  // namespace install_static