chrome/installer/util/channel_info.cc

   1 // Copyright (c) 2012 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 #include "chrome/installer/util/channel_info.h"
   6
   7 #include "base/logging.h"
   8 #include "base/win/registry.h"
   9 #include "chrome/installer/util/google_update_constants.h"
  10 #include "chrome/installer/util/util_constants.h"
  11
  12 using base::win::RegKey;
  13
  14 namespace {
  15
  16 const wchar_t kModChrome[] = L"-chrome";
  17 const wchar_t kModChromeFrame[] = L"-chromeframe";
  18 // TODO(huangs): Remove by M27.
  19 const wchar_t kModAppHostDeprecated[] = L"-apphost";
  20 const wchar_t kModAppLauncher[] = L"-applauncher";
  21 const wchar_t kModMultiInstall[] = L"-multi";
  22 const wchar_t kModReadyMode[] = L"-readymode";
  23 const wchar_t kModStage[] = L"-stage:";
  24 const wchar_t kSfxFull[] = L"-full";
  25 const wchar_t kSfxMigrating[] = L"-migrating";
  26 const wchar_t kSfxMultiFail[] = L"-multifail";
  27
  28 const wchar_t* const kChannels[] = {
  29   installer::kChromeChannelBeta,
  30   installer::kChromeChannelDev
  31 };
  32
  33 const wchar_t* const kModifiers[] = {
  34   kModStage,
  35   kModMultiInstall,
  36   kModChrome,
  37   kModChromeFrame,
  38   kModAppHostDeprecated,  // TODO(huangs): Remove by M27.
  39   kModAppLauncher,
  40   kModReadyMode,
  41   kSfxMultiFail,
  42   kSfxMigrating,
  43   kSfxFull,
  44 };
  45
  46 enum ModifierIndex {
  47   MOD_STAGE,
  48   MOD_MULTI_INSTALL,
  49   MOD_CHROME,
  50   MOD_CHROME_FRAME,
  51   MOD_APP_HOST_DEPRECATED,  // TODO(huangs): Remove by M27.
  52   MOD_APP_LAUNCHER,
  53   MOD_READY_MODE,
  54   SFX_MULTI_FAIL,
  55   SFX_MIGRATING,
  56   SFX_FULL,
  57   NUM_MODIFIERS
  58 };
  59
  60 COMPILE_ASSERT(NUM_MODIFIERS == arraysize(kModifiers),
  61     kModifiers_disagrees_with_ModifierIndex_comma_they_must_match_bang);
  62
  63 // Returns true if the modifier is found, in which case |position| holds the
  64 // location at which the modifier was found.  The number of characters in the
  65 // modifier is returned in |length|, if non-NULL.
  66 bool FindModifier(ModifierIndex index,
  67                   const std::wstring& ap_value,
  68                   std::wstring::size_type* position,
  69                   std::wstring::size_type* length) {
  70   DCHECK(position != NULL);
  71   std::wstring::size_type mod_position = std::wstring::npos;
  72   std::wstring::size_type mod_length =
  73       std::wstring::traits_type::length(kModifiers[index]);
  74   const bool mod_takes_arg = (kModifiers[index][mod_length - 1] == L':');
  75   std::wstring::size_type pos = 0;
  76   do {
  77     mod_position = ap_value.find(kModifiers[index], pos, mod_length);
  78     if (mod_position == std::wstring::npos)
  79       return false;  // Modifier not found.
  80     pos = mod_position + mod_length;
  81     // Modifiers that take an argument gobble up to the next separator or to the
  82     // end.
  83     if (mod_takes_arg) {
  84       pos = ap_value.find(L'-', pos);
  85       if (pos == std::wstring::npos)
  86         pos = ap_value.size();
  87       break;
  88     }
  89     // Regular modifiers must be followed by '-' or the end of the string.
  90   } while (pos != ap_value.size() && ap_value[pos] != L'-');
  91   DCHECK_NE(mod_position, std::wstring::npos);
  92   *position = mod_position;
  93   if (length != NULL)
  94     *length = pos - mod_position;
  95   return true;
  96 }
  97
  98 bool HasModifier(ModifierIndex index, const std::wstring& ap_value) {
  99   DCHECK(index >= 0 && index < NUM_MODIFIERS);
 100   std::wstring::size_type position;
 101   return FindModifier(index, ap_value, &position, NULL);
 102 }
 103
 104 std::wstring::size_type FindInsertionPoint(ModifierIndex index,
 105                                            const std::wstring& ap_value) {
 106   // Return the location of the next modifier.
 107   std::wstring::size_type result;
 108
 109   for (int scan = index + 1; scan < NUM_MODIFIERS; ++scan) {
 110     if (FindModifier(static_cast<ModifierIndex>(scan), ap_value, &result, NULL))
 111       return result;
 112   }
 113
 114   return ap_value.size();
 115 }
 116
 117 // Returns true if |ap_value| is modified.
 118 bool SetModifier(ModifierIndex index, bool set, std::wstring* ap_value) {
 119   DCHECK(index >= 0 && index < NUM_MODIFIERS);
 120   DCHECK(ap_value);
 121   std::wstring::size_type position;
 122   std::wstring::size_type length;
 123   bool have_modifier = FindModifier(index, *ap_value, &position, &length);
 124   if (set) {
 125     if (!have_modifier) {
 126       ap_value->insert(FindInsertionPoint(index, *ap_value), kModifiers[index]);
 127       return true;
 128     }
 129   } else {
 130     if (have_modifier) {
 131       ap_value->erase(position, length);
 132       return true;
 133     }
 134   }
 135   return false;
 136 }
 137
 138 }  // namespace
 139
 140 namespace installer {
 141
 142 bool ChannelInfo::Initialize(const RegKey& key) {
 143   LONG result = key.ReadValue(google_update::kRegApField, &value_);
 144   return result == ERROR_SUCCESS || result == ERROR_FILE_NOT_FOUND ||
 145          result == ERROR_INVALID_HANDLE;
 146 }
 147
 148 bool ChannelInfo::Write(RegKey* key) const {
 149   DCHECK(key);
 150   // Google Update deletes the value when it is empty, so we may as well, too.
 151   LONG result = value_.empty() ?
 152       key->DeleteValue(google_update::kRegApField) :
 153       key->WriteValue(google_update::kRegApField, value_.c_str());
 154   if (result != ERROR_SUCCESS) {
 155     LOG(ERROR) << "Failed writing channel info; result: " << result;
 156     return false;
 157   }
 158   return true;
 159 }
 160
 161 bool ChannelInfo::GetChannelName(std::wstring* channel_name) const {
 162   DCHECK(channel_name);
 163   if (value_.empty()) {
 164     channel_name->erase();
 165     return true;
 166   } else {
 167     for (const wchar_t* const* scan = &kChannels[0],
 168              *const* end = &kChannels[arraysize(kChannels)]; scan != end;
 169          ++scan) {
 170       if (value_.find(*scan) != std::wstring::npos) {
 171         channel_name->assign(*scan);
 172         return true;
 173       }
 174     }
 175     // There may be modifiers present.  Strip them off and see if we're left
 176     // with the empty string (stable channel).
 177     std::wstring tmp_value = value_;
 178     for (int i = 0; i != NUM_MODIFIERS; ++i) {
 179       SetModifier(static_cast<ModifierIndex>(i), false, &tmp_value);
 180     }
 181     if (tmp_value.empty()) {
 182       channel_name->erase();
 183       return true;
 184     }
 185   }
 186
 187   return false;
 188 }
 189
 190 bool ChannelInfo::IsChrome() const {
 191   return HasModifier(MOD_CHROME, value_);
 192 }
 193
 194 bool ChannelInfo::SetChrome(bool value) {
 195   return SetModifier(MOD_CHROME, value, &value_);
 196 }
 197
 198 bool ChannelInfo::IsChromeFrame() const {
 199   return HasModifier(MOD_CHROME_FRAME, value_);
 200 }
 201
 202 bool ChannelInfo::SetChromeFrame(bool value) {
 203   return SetModifier(MOD_CHROME_FRAME, value, &value_);
 204 }
 205
 206 bool ChannelInfo::IsAppLauncher() const {
 207   return HasModifier(MOD_APP_LAUNCHER, value_);
 208 }
 209
 210 bool ChannelInfo::SetAppLauncher(bool value) {
 211   // Unconditionally remove -apphost since it has been deprecated.
 212   bool changed_app_host = SetModifier(MOD_APP_HOST_DEPRECATED, false, &value_);
 213   bool changed_app_launcher = SetModifier(MOD_APP_LAUNCHER, value, &value_);
 214   return changed_app_host || changed_app_launcher;
 215 }
 216
 217 bool ChannelInfo::IsMultiInstall() const {
 218   return HasModifier(MOD_MULTI_INSTALL, value_);
 219 }
 220
 221 bool ChannelInfo::SetMultiInstall(bool value) {
 222   return SetModifier(MOD_MULTI_INSTALL, value, &value_);
 223 }
 224
 225 bool ChannelInfo::IsReadyMode() const {
 226   return HasModifier(MOD_READY_MODE, value_);
 227 }
 228
 229 bool ChannelInfo::SetReadyMode(bool value) {
 230   return SetModifier(MOD_READY_MODE, value, &value_);
 231 }
 232
 233 bool ChannelInfo::SetStage(const wchar_t* stage) {
 234   std::wstring::size_type position;
 235   std::wstring::size_type length;
 236   bool have_modifier = FindModifier(MOD_STAGE, value_, &position, &length);
 237   if (stage != NULL && *stage != L'\0') {
 238     std::wstring stage_str(kModStage);
 239     stage_str.append(stage);
 240     if (!have_modifier) {
 241       value_.insert(FindInsertionPoint(MOD_STAGE, value_), stage_str);
 242       return true;
 243     }
 244     if (value_.compare(position, length, stage_str) != 0) {
 245       value_.replace(position, length, stage_str);
 246       return true;
 247     }
 248   } else {
 249     if (have_modifier) {
 250       value_.erase(position, length);
 251       return true;
 252     }
 253   }
 254   return false;
 255 }
 256
 257 std::wstring ChannelInfo::GetStage() const {
 258   std::wstring::size_type position;
 259   std::wstring::size_type length;
 260
 261   if (FindModifier(MOD_STAGE, value_, &position, &length)) {
 262     // Return the portion after the prefix.
 263     std::wstring::size_type pfx_length =
 264         std::wstring::traits_type::length(kModStage);
 265     DCHECK_LE(pfx_length, length);
 266     return value_.substr(position + pfx_length, length - pfx_length);
 267   }
 268   return std::wstring();
 269 }
 270
 271 bool ChannelInfo::HasFullSuffix() const {
 272   return HasModifier(SFX_FULL, value_);
 273 }
 274
 275 bool ChannelInfo::SetFullSuffix(bool value) {
 276   return SetModifier(SFX_FULL, value, &value_);
 277 }
 278
 279 bool ChannelInfo::HasMultiFailSuffix() const {
 280   return HasModifier(SFX_MULTI_FAIL, value_);
 281 }
 282
 283 bool ChannelInfo::SetMultiFailSuffix(bool value) {
 284   return SetModifier(SFX_MULTI_FAIL, value, &value_);
 285 }
 286
 287 bool ChannelInfo::SetMigratingSuffix(bool value) {
 288   return SetModifier(SFX_MIGRATING, value, &value_);
 289 }
 290
 291 bool ChannelInfo::HasMigratingSuffix() const {
 292   return HasModifier(SFX_MIGRATING, value_);
 293 }
 294
 295 bool ChannelInfo::RemoveAllModifiersAndSuffixes() {
 296   bool modified = false;
 297
 298   for (int scan = 0; scan < NUM_MODIFIERS; ++scan) {
 299     ModifierIndex index = static_cast<ModifierIndex>(scan);
 300     modified = SetModifier(index, false, &value_) || modified;
 301   }
 302
 303   return modified;
 304 }
 305
 306 }  // namespace installer