root/extensions/common/manifest_handler.cc

DEFINITIONS

1. GetRegistry
2. Validate
3. AlwaysParseForType
4. AlwaysValidateForType
5. PrerequisiteKeys
6. Register
7. CreatePermission
8. CreateInitialRequiredPermission
9. FinalizeRegistration
10. IsRegistrationFinalized
11. ParseExtension
12. ValidateExtension
13. CreatePermission
14. AddExtensionInitialRequiredPermissions
15. SingleKey
16. Finalize
17. RegisterManifestHandler
18. ParseExtension
19. ValidateExtension
20. CreatePermission
21. AddExtensionInitialRequiredPermissions
22. SetForTesting
23. SortManifestHandlers

// Copyright (c) 2013 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 "extensions/common/manifest_handler.h"

#include <map>

#include "base/logging.h"
#include "base/stl_util.h"
#include "extensions/common/extension.h"
#include "extensions/common/permissions/manifest_permission.h"
#include "extensions/common/permissions/manifest_permission_set.h"

namespace extensions {

namespace {

static base::LazyInstance<ManifestHandlerRegistry> g_registry =
    LAZY_INSTANCE_INITIALIZER;
static ManifestHandlerRegistry* g_registry_override = NULL;

ManifestHandlerRegistry* GetRegistry() {
  if (!g_registry_override)
    return g_registry.Pointer();
  return g_registry_override;
}

}  // namespace

ManifestHandler::ManifestHandler() {
}

ManifestHandler::~ManifestHandler() {
}

bool ManifestHandler::Validate(const Extension* extension,
                               std::string* error,
                               std::vector<InstallWarning>* warnings) const {
  return true;
}

bool ManifestHandler::AlwaysParseForType(Manifest::Type type) const {
  return false;
}

bool ManifestHandler::AlwaysValidateForType(Manifest::Type type) const {
  return false;
}

const std::vector<std::string> ManifestHandler::PrerequisiteKeys() const {
  return std::vector<std::string>();
}

void ManifestHandler::Register() {
  linked_ptr<ManifestHandler> this_linked(this);
  const std::vector<std::string> keys = Keys();
  for (size_t i = 0; i < keys.size(); ++i)
    GetRegistry()->RegisterManifestHandler(keys[i], this_linked);
}

ManifestPermission* ManifestHandler::CreatePermission() {
  return NULL;
}

ManifestPermission* ManifestHandler::CreateInitialRequiredPermission(
    const Extension* extension) {
  return NULL;
}

// static
void ManifestHandler::FinalizeRegistration() {
  GetRegistry()->Finalize();
}

// static
bool ManifestHandler::IsRegistrationFinalized() {
  return GetRegistry()->is_finalized_;
}

// static
bool ManifestHandler::ParseExtension(Extension* extension,
                                     base::string16* error) {
  return GetRegistry()->ParseExtension(extension, error);
}

// static
bool ManifestHandler::ValidateExtension(const Extension* extension,
                                        std::string* error,
                                        std::vector<InstallWarning>* warnings) {
  return GetRegistry()->ValidateExtension(extension, error, warnings);
}

// static
ManifestPermission* ManifestHandler::CreatePermission(const std::string& name) {
  return GetRegistry()->CreatePermission(name);
}

// static
void ManifestHandler::AddExtensionInitialRequiredPermissions(
    const Extension* extension, ManifestPermissionSet* permission_set) {
  return GetRegistry()->AddExtensionInitialRequiredPermissions(extension,
                                                               permission_set);
}

// static
const std::vector<std::string> ManifestHandler::SingleKey(
    const std::string& key) {
  return std::vector<std::string>(1, key);
}

ManifestHandlerRegistry::ManifestHandlerRegistry() : is_finalized_(false) {
}

ManifestHandlerRegistry::~ManifestHandlerRegistry() {
}

void ManifestHandlerRegistry::Finalize() {
  CHECK(!is_finalized_);
  SortManifestHandlers();
  is_finalized_ = true;
}

void ManifestHandlerRegistry::RegisterManifestHandler(
    const std::string& key, linked_ptr<ManifestHandler> handler) {
  CHECK(!is_finalized_);
  handlers_[key] = handler;
}

bool ManifestHandlerRegistry::ParseExtension(Extension* extension,
                                             base::string16* error) {
  std::map<int, ManifestHandler*> handlers_by_priority;
  for (ManifestHandlerMap::iterator iter = handlers_.begin();
       iter != handlers_.end(); ++iter) {
    ManifestHandler* handler = iter->second.get();
    if (extension->manifest()->HasPath(iter->first) ||
        handler->AlwaysParseForType(extension->GetType())) {
      handlers_by_priority[priority_map_[handler]] = handler;
    }
  }
  for (std::map<int, ManifestHandler*>::iterator iter =
           handlers_by_priority.begin();
       iter != handlers_by_priority.end(); ++iter) {
    if (!(iter->second)->Parse(extension, error))
      return false;
  }
  return true;
}

bool ManifestHandlerRegistry::ValidateExtension(
    const Extension* extension,
    std::string* error,
    std::vector<InstallWarning>* warnings) {
  std::set<ManifestHandler*> handlers;
  for (ManifestHandlerMap::iterator iter = handlers_.begin();
       iter != handlers_.end(); ++iter) {
    ManifestHandler* handler = iter->second.get();
    if (extension->manifest()->HasPath(iter->first) ||
        handler->AlwaysValidateForType(extension->GetType())) {
      handlers.insert(handler);
    }
  }
  for (std::set<ManifestHandler*>::iterator iter = handlers.begin();
       iter != handlers.end(); ++iter) {
    if (!(*iter)->Validate(extension, error, warnings))
      return false;
  }
  return true;
}

ManifestPermission* ManifestHandlerRegistry::CreatePermission(
    const std::string& name) {
  ManifestHandlerMap::const_iterator it = handlers_.find(name);
  if (it == handlers_.end())
    return NULL;

  return it->second->CreatePermission();
}

void ManifestHandlerRegistry::AddExtensionInitialRequiredPermissions(
    const Extension* extension, ManifestPermissionSet* permission_set) {
  for (ManifestHandlerMap::const_iterator it = handlers_.begin();
      it != handlers_.end(); ++it) {
    ManifestPermission* permission =
        it->second->CreateInitialRequiredPermission(extension);
    if (permission) {
      permission_set->insert(permission);
    }
  }
}

// static
ManifestHandlerRegistry* ManifestHandlerRegistry::SetForTesting(
    ManifestHandlerRegistry* new_registry) {
  ManifestHandlerRegistry* old_registry = GetRegistry();
  if (new_registry != g_registry.Pointer())
    g_registry_override = new_registry;
  else
    g_registry_override = NULL;
  return old_registry;
}

void ManifestHandlerRegistry::SortManifestHandlers() {
  std::set<ManifestHandler*> unsorted_handlers;
  for (ManifestHandlerMap::const_iterator iter = handlers_.begin();
       iter != handlers_.end(); ++iter) {
    unsorted_handlers.insert(iter->second.get());
  }

  int priority = 0;
  while (true) {
    std::set<ManifestHandler*> next_unsorted_handlers;
    for (std::set<ManifestHandler*>::const_iterator iter =
             unsorted_handlers.begin();
         iter != unsorted_handlers.end(); ++iter) {
      ManifestHandler* handler = *iter;
      const std::vector<std::string>& prerequisites =
          handler->PrerequisiteKeys();
      int unsatisfied = prerequisites.size();
      for (size_t i = 0; i < prerequisites.size(); ++i) {
        ManifestHandlerMap::const_iterator prereq_iter =
            handlers_.find(prerequisites[i]);
        // If the prerequisite does not exist, crash.
        CHECK(prereq_iter != handlers_.end())
            << "Extension manifest handler depends on unrecognized key "
            << prerequisites[i];
        // Prerequisite is in our map.
        if (ContainsKey(priority_map_, prereq_iter->second.get()))
          unsatisfied--;
      }
      if (unsatisfied == 0) {
        priority_map_[handler] = priority;
        priority++;
      } else {
        // Put in the list for next time.
        next_unsorted_handlers.insert(handler);
      }
    }
    if (next_unsorted_handlers.size() == unsorted_handlers.size())
      break;
    unsorted_handlers.swap(next_unsorted_handlers);
  }

  // If there are any leftover unsorted handlers, they must have had
  // circular dependencies.
  CHECK(unsorted_handlers.size() == 0) << "Extension manifest handlers have "
                                       << "circular dependencies!";
}

}  // namespace extensions