Revert 194643 "Remove scoped_array usage from RegistryKeyBackup."

trunk/src/chrome/installer/util/registry_key_backup.cc

Index: trunk/src/chrome/installer/util/registry_key_backup.cc
===================================================================
--- trunk/src/chrome/installer/util/registry_key_backup.cc	(revision 194653)
+++ trunk/src/chrome/installer/util/registry_key_backup.cc	(working copy)
@@ -5,8 +5,7 @@
 #include "chrome/installer/util/registry_key_backup.h"
 
 #include <algorithm>
-#include <map>
-#include <utility>
+#include <limits>
 #include <vector>
 
 #include "base/logging.h"
@@ -15,11 +14,47 @@
 using base::win::RegKey;
 
 namespace {
-
 const REGSAM kKeyReadNoNotify = (KEY_READ) & ~(KEY_NOTIFY);
+}  // namespace
 
+// A container for a registry key, its values, and its subkeys.
+class RegistryKeyBackup::KeyData {
+ public:
+  KeyData();
+  ~KeyData();
+
+  // Initializes this object by reading the values and subkeys of |key|.
+  // Security descriptors are not backed up.  Returns true if the operation was
+  // successful; false otherwise, in which case the state of this object is not
+  // modified.
+  bool Initialize(const RegKey& key);
+
+  // Writes the contents of this object to |key|, which must have been opened
+  // with at least REG_SET_VALUE and KEY_CREATE_SUB_KEY access rights.  Returns
+  // true if the operation was successful; false otherwise, in which case the
+  // contents of |key| may have been modified.
+  bool WriteTo(RegKey* key) const;
+
+ private:
+  class ValueData;
+
+  // The values of this key.
+  scoped_array<ValueData> values_;
+  // The names of this key's sub-keys (the data for subkey_names_[i] is in
+  // subkeys_[i]).
+  scoped_array<std::wstring> subkey_names_;
+  // The key data of this key's sub-keys.
+  scoped_array<KeyData> subkeys_;
+  // The number of values for this key.
+  DWORD num_values_;
+  // The number of subkeys for this key.
+  DWORD num_subkeys_;
+
+  DISALLOW_COPY_AND_ASSIGN(KeyData);
+};
+
 // A container for a registry value.
-class ValueData {
+class RegistryKeyBackup::KeyData::ValueData {
  public:
   ValueData();
   ~ValueData();
@@ -54,45 +89,18 @@
   // This value's type (e.g., REG_DWORD, REG_SZ, REG_QWORD, etc).
   DWORD type_;
 
-  // Copy constructible and assignable for use in STL containers.
+  DISALLOW_COPY_AND_ASSIGN(ValueData);
 };
 
-}  // namespace
-
-// A container for a registry key, its values, and its subkeys.
-class RegistryKeyBackup::KeyData {
- public:
-  KeyData();
-  ~KeyData();
-
-  // Initializes this object by reading the values and subkeys of |key|.
-  // Security descriptors are not backed up.  Returns true if the operation was
-  // successful; false otherwise, in which case the state of this object is not
-  // modified.
-  bool Initialize(const RegKey& key);
-
-  // Writes the contents of this object to |key|, which must have been opened
-  // with at least REG_SET_VALUE and KEY_CREATE_SUB_KEY access rights.  Returns
-  // true if the operation was successful; false otherwise, in which case the
-  // contents of |key| may have been modified.
-  bool WriteTo(RegKey* key) const;
-
- private:
-  // The values of this key.
-  std::vector<ValueData> values_;
-  // Map of subkey names to the corresponding KeyData.
-  std::map<std::wstring, KeyData> subkeys_;
-
-  // Copy constructible and assignable for use in STL containers.
-};
-
-ValueData::ValueData() : type_(REG_NONE) {
+RegistryKeyBackup::KeyData::ValueData::ValueData()
+    : type_(REG_NONE) {
 }
 
-ValueData::~ValueData() {
+RegistryKeyBackup::KeyData::ValueData::~ValueData()
+{
 }
 
-void ValueData::Initialize(
+void RegistryKeyBackup::KeyData::ValueData::Initialize(
     const wchar_t* name_buffer,
     DWORD name_size,
     DWORD type,
@@ -103,15 +111,19 @@
   data_.assign(data, data + data_size);
 }
 
-RegistryKeyBackup::KeyData::KeyData() {
+RegistryKeyBackup::KeyData::KeyData()
+    : num_values_(0),
+      num_subkeys_(0) {
 }
 
-RegistryKeyBackup::KeyData::~KeyData() {
+RegistryKeyBackup::KeyData::~KeyData()
+{
 }
 
 bool RegistryKeyBackup::KeyData::Initialize(const RegKey& key) {
-  std::vector<ValueData> values;
-  std::map<std::wstring, KeyData> subkeys;
+  scoped_array<ValueData> values;
+  scoped_array<std::wstring> subkey_names;
+  scoped_array<KeyData> subkeys;
 
   DWORD num_subkeys = 0;
   DWORD max_subkey_name_len = 0;
@@ -126,38 +138,52 @@
     LOG(ERROR) << "Failed getting info of key to backup, result: " << result;
     return false;
   }
+  if (max_subkey_name_len >= std::numeric_limits<DWORD>::max() - 1 ||
+      max_value_name_len >= std::numeric_limits<DWORD>::max() - 1) {
+    LOG(ERROR)
+        << "Failed backing up key; subkeys and/or names are out of range.";
+    return false;
+  }
   DWORD max_name_len = std::max(max_subkey_name_len, max_value_name_len) + 1;
-  std::vector<wchar_t> name_buffer(max_name_len);
+  scoped_array<wchar_t> name_buffer(new wchar_t[max_name_len]);
 
   // Backup the values.
   if (num_values != 0) {
-    values.reserve(num_values);
-    std::vector<uint8> value_buffer(max_value_len != 0 ? max_value_len : 1);
+    values.reset(new ValueData[num_values]);
+    scoped_array<uint8> value_buffer(new uint8[max_value_len]);
     DWORD name_size = 0;
     DWORD value_type = REG_NONE;
     DWORD value_size = 0;
 
     for (DWORD i = 0; i < num_values; ) {
-      name_size = name_buffer.size();
-      value_size = value_buffer.size();
-      result = RegEnumValue(key.Handle(), i, &name_buffer[0], &name_size,
-                            NULL, &value_type, &value_buffer[0], &value_size);
+      name_size = max_name_len;
+      value_size = max_value_len;
+      result = RegEnumValue(key.Handle(), i, name_buffer.get(), &name_size,
+                            NULL, &value_type, value_buffer.get(), &value_size);
       switch (result) {
         case ERROR_NO_MORE_ITEMS:
           num_values = i;
           break;
         case ERROR_SUCCESS:
-          values.push_back(ValueData());
-          values.back().Initialize(&name_buffer[0], name_size, value_type,
-                                   &value_buffer[0], value_size);
+          values[i].Initialize(name_buffer.get(), name_size, value_type,
+                               value_buffer.get(), value_size);
           ++i;
           break;
         case ERROR_MORE_DATA:
-          if (value_size > value_buffer.size())
-            value_buffer.resize(value_size);
-          // |name_size| does not include space for the terminating NULL.
-          if (name_size + 1 > name_buffer.size())
-            name_buffer.resize(name_size + 1);
+          if (value_size > max_value_len) {
+            max_value_len = value_size;
+            value_buffer.reset();  // Release to heap before new allocation.
+            value_buffer.reset(new uint8[max_value_len]);
+          } else {
+            DCHECK_LT(max_name_len - 1, name_size);
+            if (name_size >= std::numeric_limits<DWORD>::max() - 1) {
+              LOG(ERROR) << "Failed backing up key; value name out of range.";
+              return false;
+            }
+            max_name_len = name_size + 1;
+            name_buffer.reset();  // Release to heap before new allocation.
+            name_buffer.reset(new wchar_t[max_name_len]);
+          }
           break;
         default:
           LOG(ERROR) << "Failed backing up value " << i << ", result: "
@@ -165,7 +191,7 @@
           return false;
       }
     }
-    DLOG_IF(WARNING, RegEnumValue(key.Handle(), num_values, &name_buffer[0],
+    DLOG_IF(WARNING, RegEnumValue(key.Handle(), num_values, name_buffer.get(),
                                   &name_size, NULL, &value_type, NULL,
                                   NULL) != ERROR_NO_MORE_ITEMS)
         << "Concurrent modifications to registry key during backup operation.";
@@ -173,23 +199,30 @@
 
   // Backup the subkeys.
   if (num_subkeys != 0) {
+    subkey_names.reset(new std::wstring[num_subkeys]);
+    subkeys.reset(new KeyData[num_subkeys]);
     DWORD name_size = 0;
 
     // Get the names of them.
     for (DWORD i = 0; i < num_subkeys; ) {
-      name_size = name_buffer.size();
-      result = RegEnumKeyEx(key.Handle(), i, &name_buffer[0], &name_size,
+      name_size = max_name_len;
+      result = RegEnumKeyEx(key.Handle(), i, name_buffer.get(), &name_size,
                             NULL, NULL, NULL, NULL);
       switch (result) {
         case ERROR_NO_MORE_ITEMS:
           num_subkeys = i;
           break;
         case ERROR_SUCCESS:
-          subkeys.insert(std::make_pair(&name_buffer[0], KeyData()));
+          subkey_names[i].assign(name_buffer.get(), name_size);
           ++i;
           break;
         case ERROR_MORE_DATA:
-          name_buffer.resize(name_size + 1);
+          if (name_size >= std::numeric_limits<DWORD>::max() - 1) {
+            LOG(ERROR) << "Failed backing up key; subkey name out of range.";
+            return false;
+          }
+          max_name_len = name_size + 1;
+          name_buffer.reset(new wchar_t[max_name_len]);
           break;
         default:
           LOG(ERROR) << "Failed getting name of subkey " << i
@@ -204,23 +237,26 @@
 
     // Get their values.
     RegKey subkey;
-    for (std::map<std::wstring, KeyData>::iterator it = subkeys.begin();
-         it != subkeys.end(); ++it) {
-      result = subkey.Open(key.Handle(), it->first.c_str(), kKeyReadNoNotify);
+    for (DWORD i = 0; i < num_subkeys; ++i) {
+      result = subkey.Open(key.Handle(), subkey_names[i].c_str(),
+                           kKeyReadNoNotify);
       if (result != ERROR_SUCCESS) {
-        LOG(ERROR) << "Failed opening subkey \"" << it->first
+        LOG(ERROR) << "Failed opening subkey \"" << subkey_names[i]
                    << "\" for backup, result: " << result;
         return false;
       }
-      if (!it->second.Initialize(subkey)) {
-        LOG(ERROR) << "Failed backing up subkey \"" << it->first << "\"";
+      if (!subkeys[i].Initialize(subkey)) {
+        LOG(ERROR) << "Failed backing up subkey \"" << subkey_names[i] << "\"";
         return false;
       }
     }
   }
 
   values_.swap(values);
+  subkey_names_.swap(subkey_names);
   subkeys_.swap(subkeys);
+  num_values_ = num_values;
+  num_subkeys_ = num_subkeys;
 
   return true;
 }
@@ -231,9 +267,8 @@
   LONG result = ERROR_SUCCESS;
 
   // Write the values.
-  for (std::vector<ValueData>::const_iterator it = values_.begin();
-       it != values_.end(); ++it) {
-    const ValueData& value = *it;
+  for (DWORD i = 0; i < num_values_; ++i) {
+    const ValueData& value = values_[i];
     result = RegSetValueEx(key->Handle(), value.name(), 0, value.type(),
                            value.data(), value.data_len());
     if (result != ERROR_SUCCESS) {
@@ -245,9 +280,8 @@
 
   // Write the subkeys.
   RegKey subkey;
-  for (std::map<std::wstring, KeyData>::const_iterator it = subkeys_.begin();
-       it != subkeys_.end(); ++it) {
-    const std::wstring& name = it->first;
+  for (DWORD i = 0; i < num_subkeys_; ++i) {
+    const std::wstring& name = subkey_names_[i];
 
     result = subkey.Create(key->Handle(), name.c_str(), KEY_WRITE);
     if (result != ERROR_SUCCESS) {
@@ -255,7 +289,7 @@
                  << result;
       return false;
     }
-    if (!it->second.WriteTo(&subkey)) {
+    if (!subkeys_[i].WriteTo(&subkey)) {
       LOG(ERROR) << "Failed writing subkey \"" << name << "\", result: "
                  << result;
       return false;