/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-

 * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include <limits.h>

#include <stdio.h>

#include "nsError.h"

#include "nsMemory.h"

#include "nsProxyRelease.h"

#include "nsThreadUtils.h"

#include "nsIClassInfoImpl.h"

#include "Variant.h"

#include "mozIStorageError.h"

#include "mozStorageBindingParams.h"

#include "mozStorageConnection.h"

#include "mozStorageAsyncStatementJSHelper.h"

#include "mozStorageAsyncStatementParams.h"

#include "mozStoragePrivateHelpers.h"

#include "mozStorageStatementRow.h"

#include "mozStorageStatement.h"

#include "mozilla/Logging.h"

extern mozilla::LazyLogModule gStorageLog;

namespace mozilla {

namespace storage {

////////////////////////////////////////////////////////////////////////////////

//// nsIClassInfo

NS_IMPL_CI_INTERFACE_GETTER(AsyncStatement,

                            mozIStorageAsyncStatement,

                            mozIStorageBaseStatement,

                            mozIStorageBindingParams,

                            mozilla::storage::StorageBaseStatementInternal)

class AsyncStatementClassInfo : public nsIClassInfo

{

public:

  constexpr AsyncStatementClassInfo() {}

  NS_DECL_ISUPPORTS_INHERITED

  NS_IMETHOD

  GetInterfaces(uint32_t *_count, nsIID ***_array) override

  {

    return NS_CI_INTERFACE_GETTER_NAME(AsyncStatement)(_count, _array);

  }

  NS_IMETHOD

  GetScriptableHelper(nsIXPCScriptable **_helper) override

  {

    static AsyncStatementJSHelper sJSHelper;

    *_helper = &sJSHelper;

    return NS_OK;

  }

  NS_IMETHOD

  GetContractID(nsACString& aContractID) override

  {

    aContractID.SetIsVoid(true);

    return NS_OK;

  }

  NS_IMETHOD

  GetClassDescription(nsACString& aDesc) override

  {

    aDesc.SetIsVoid(true);

    return NS_OK;

  }

  NS_IMETHOD

  GetClassID(nsCID **_id) override

  {

    *_id = nullptr;

    return NS_OK;

  }

  NS_IMETHOD

  GetFlags(uint32_t *_flags) override

  {

    *_flags = 0;

    return NS_OK;

  }

  NS_IMETHOD

  GetClassIDNoAlloc(nsCID *_cid) override

  {

    return NS_ERROR_NOT_AVAILABLE;

  }

};

NS_IMETHODIMP_(MozExternalRefCountType) AsyncStatementClassInfo::AddRef() { return 2; }

NS_IMETHODIMP_(MozExternalRefCountType) AsyncStatementClassInfo::Release() { return 1; }

NS_IMPL_QUERY_INTERFACE(AsyncStatementClassInfo, nsIClassInfo)

static AsyncStatementClassInfo sAsyncStatementClassInfo;

////////////////////////////////////////////////////////////////////////////////

//// AsyncStatement

AsyncStatement::AsyncStatement()

: StorageBaseStatementInternal()

, mFinalized(false)

{

}

nsresult

AsyncStatement::initialize(Connection *aDBConnection,

                           sqlite3 *aNativeConnection,

                           const nsACString &aSQLStatement)

{

  MOZ_ASSERT(aDBConnection, "No database connection given!");

  MOZ_ASSERT(aDBConnection->isConnectionReadyOnThisThread(), "Database connection should be valid");

  MOZ_ASSERT(aNativeConnection, "No native connection given!");

  mDBConnection = aDBConnection;

  mNativeConnection = aNativeConnection;

  mSQLString = aSQLStatement;

  MOZ_LOG(gStorageLog, LogLevel::Debug, ("Inited async statement '%s' (0x%p)",

                                      mSQLString.get(), this));

#ifdef DEBUG

  // We want to try and test for LIKE and that consumers are using

  // escapeStringForLIKE instead of just trusting user input.  The idea to

  // check to see if they are binding a parameter after like instead of just

  // using a string.  We only do this in debug builds because it's expensive!

  const nsCaseInsensitiveCStringComparator c;

  nsACString::const_iterator start, end, e;

  aSQLStatement.BeginReading(start);

  aSQLStatement.EndReading(end);

  e = end;

  while (::FindInReadable(NS_LITERAL_CSTRING(" LIKE"), start, e, c)) {

    // We have a LIKE in here, so we perform our tests

    // FindInReadable moves the iterator, so we have to get a new one for

    // each test we perform.

    nsACString::const_iterator s1, s2, s3;

    s1 = s2 = s3 = start;

    if (!(::FindInReadable(NS_LITERAL_CSTRING(" LIKE ?"), s1, end, c) ||

          ::FindInReadable(NS_LITERAL_CSTRING(" LIKE :"), s2, end, c) ||

          ::FindInReadable(NS_LITERAL_CSTRING(" LIKE @"), s3, end, c))) {

      // At this point, we didn't find a LIKE statement followed by ?, :,

      // or @, all of which are valid characters for binding a parameter.

      // We will warn the consumer that they may not be safely using LIKE.

      NS_WARNING("Unsafe use of LIKE detected!  Please ensure that you "

                 "are using mozIStorageAsyncStatement::escapeStringForLIKE "

                 "and that you are binding that result to the statement "

                 "to prevent SQL injection attacks.");

    }

    // resetting start and e

    start = e;

    e = end;

  }

#endif

  return NS_OK;

}

mozIStorageBindingParams *

AsyncStatement::getParams()

{

  nsresult rv;

  // If we do not have an array object yet, make it.

  if (!mParamsArray) {

    nsCOMPtr<mozIStorageBindingParamsArray> array;

    rv = NewBindingParamsArray(getter_AddRefs(array));

    NS_ENSURE_SUCCESS(rv, nullptr);

    mParamsArray = static_cast<BindingParamsArray *>(array.get());

  }

  // If there isn't already any rows added, we'll have to add one to use.

  if (mParamsArray->length() == 0) {

    RefPtr<AsyncBindingParams> params(new AsyncBindingParams(mParamsArray));

    NS_ENSURE_TRUE(params, nullptr);

    rv = mParamsArray->AddParams(params);

    NS_ENSURE_SUCCESS(rv, nullptr);

    // We have to unlock our params because AddParams locks them.  This is safe

    // because no reference to the params object was, or ever will be given out.

    params->unlock(nullptr);

    // We also want to lock our array at this point - we don't want anything to

    // be added to it.

    mParamsArray->lock();

  }

  return *mParamsArray->begin();

}

/**

 * If we are here then we know there are no pending async executions relying on

 * us (StatementData holds a reference to us; this also goes for our own

 * AsyncStatementFinalizer which proxies its release to the calling thread) and

 * so it is always safe to destroy our sqlite3_stmt if one exists.  We can be

 * destroyed on the caller thread by garbage-collection/reference counting or on

 * the async thread by the last execution of a statement that already lost its

 * main-thread refs.

 */

AsyncStatement::~AsyncStatement()

{

  destructorAsyncFinalize();

  // If we are getting destroyed on the wrong thread, proxy the connection

  // release to the right thread.  I'm not sure why we do this.

  bool onCallingThread = false;

  (void)mDBConnection->threadOpenedOn->IsOnCurrentThread(&onCallingThread);

  if (!onCallingThread) {

    // NS_ProxyRelase only magic forgets for us if mDBConnection is an

    // nsCOMPtr.  Which it is not; it's an nsRefPtr.

    nsCOMPtr<nsIThread> targetThread(mDBConnection->threadOpenedOn);

    NS_ProxyRelease(

      "AsyncStatement::mDBConnection",

      targetThread, mDBConnection.forget());

  }

}

////////////////////////////////////////////////////////////////////////////////

//// nsISupports

NS_IMPL_ADDREF(AsyncStatement)

NS_IMPL_RELEASE(AsyncStatement)

NS_INTERFACE_MAP_BEGIN(AsyncStatement)

  NS_INTERFACE_MAP_ENTRY(mozIStorageAsyncStatement)

  NS_INTERFACE_MAP_ENTRY(mozIStorageBaseStatement)

  NS_INTERFACE_MAP_ENTRY(mozIStorageBindingParams)

  NS_INTERFACE_MAP_ENTRY(mozilla::storage::StorageBaseStatementInternal)

  if (aIID.Equals(NS_GET_IID(nsIClassInfo))) {

    foundInterface = static_cast<nsIClassInfo *>(&sAsyncStatementClassInfo);

  }

  else

  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, mozIStorageAsyncStatement)

NS_INTERFACE_MAP_END

////////////////////////////////////////////////////////////////////////////////

//// StorageBaseStatementInternal

Connection *

AsyncStatement::getOwner()

{

  return mDBConnection;

}

int

AsyncStatement::getAsyncStatement(sqlite3_stmt **_stmt)

{

#ifdef DEBUG

  // Make sure we are never called on the connection's owning thread.

  bool onOpenedThread = false;

  (void)mDBConnection->threadOpenedOn->IsOnCurrentThread(&onOpenedThread);

  NS_ASSERTION(!onOpenedThread,

               "We should only be called on the async thread!");

#endif

  if (!mAsyncStatement) {

    int rc = mDBConnection->prepareStatement(mNativeConnection, mSQLString,

                                             &mAsyncStatement);

    if (rc != SQLITE_OK) {

      MOZ_LOG(gStorageLog, LogLevel::Error,

             ("Sqlite statement prepare error: %d '%s'", rc,

              ::sqlite3_errmsg(mNativeConnection)));

      MOZ_LOG(gStorageLog, LogLevel::Error,

             ("Statement was: '%s'", mSQLString.get()));

      *_stmt = nullptr;

      return rc;

    }

    MOZ_LOG(gStorageLog, LogLevel::Debug, ("Initialized statement '%s' (0x%p)",

                                        mSQLString.get(),

                                        mAsyncStatement));

  }

  *_stmt = mAsyncStatement;

  return SQLITE_OK;

}

nsresult

AsyncStatement::getAsynchronousStatementData(StatementData &_data)

{

  if (mFinalized)

    return NS_ERROR_UNEXPECTED;

  // Pass null for the sqlite3_stmt; it will be requested on demand from the

  // async thread.

  _data = StatementData(nullptr, bindingParamsArray(), this);

  return NS_OK;

}

already_AddRefed<mozIStorageBindingParams>

AsyncStatement::newBindingParams(mozIStorageBindingParamsArray *aOwner)

{

  if (mFinalized)

    return nullptr;

  nsCOMPtr<mozIStorageBindingParams> params(new AsyncBindingParams(aOwner));

  return params.forget();

}

////////////////////////////////////////////////////////////////////////////////

//// mozIStorageAsyncStatement

// (nothing is specific to mozIStorageAsyncStatement)

////////////////////////////////////////////////////////////////////////////////

//// StorageBaseStatementInternal

// proxy to StorageBaseStatementInternal using its define helper.

MIXIN_IMPL_STORAGEBASESTATEMENTINTERNAL(

  AsyncStatement,

  if (mFinalized) return NS_ERROR_UNEXPECTED;)

NS_IMETHODIMP

AsyncStatement::Finalize()

{

  if (mFinalized)

    return NS_OK;

  mFinalized = true;

  MOZ_LOG(gStorageLog, LogLevel::Debug, ("Finalizing statement '%s'",

                                      mSQLString.get()));

  asyncFinalize();

  // Release the params holder, so it can release the reference to us.

  mStatementParamsHolder = nullptr;

  return NS_OK;

}

NS_IMETHODIMP

AsyncStatement::BindParameters(mozIStorageBindingParamsArray *aParameters)

{

  if (mFinalized)

    return NS_ERROR_UNEXPECTED;

  BindingParamsArray *array = static_cast<BindingParamsArray *>(aParameters);

  if (array->getOwner() != this)

    return NS_ERROR_UNEXPECTED;

  if (array->length() == 0)

    return NS_ERROR_UNEXPECTED;

  mParamsArray = array;

  mParamsArray->lock();

  return NS_OK;

}

NS_IMETHODIMP

AsyncStatement::GetState(int32_t *_state)

{

  if (mFinalized)

    *_state = MOZ_STORAGE_STATEMENT_INVALID;

  else

    *_state = MOZ_STORAGE_STATEMENT_READY;

  return NS_OK;

}

////////////////////////////////////////////////////////////////////////////////

//// mozIStorageBindingParams

BOILERPLATE_BIND_PROXIES(

  AsyncStatement,

  if (mFinalized) return NS_ERROR_UNEXPECTED;

)

} // namespace storage

} // namespace mozilla