/* -*- 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 "storage_test_harness.h" #include "prthread.h" #include "nsIEventTarget.h" #include "nsIInterfaceRequestorUtils.h" #include "sqlite3.h" #include "mozilla/ReentrantMonitor.h" using mozilla::ReentrantMonitor; using mozilla::ReentrantMonitorAutoEnter; /** * Verify that mozIStorageAsyncStatement's life-cycle never triggers a mutex on * the caller (generally main) thread. We do this by decorating the sqlite * mutex logic with our own code that checks what thread it is being invoked on * and sets a flag if it is invoked on the main thread. We are able to easily * decorate the SQLite mutex logic because SQLite allows us to retrieve the * current function pointers being used and then provide a new set. */ /* ===== Mutex Watching ===== */ sqlite3_mutex_methods orig_mutex_methods; sqlite3_mutex_methods wrapped_mutex_methods; bool mutex_used_on_watched_thread = false; PRThread *watched_thread = NULL; /** * Ugly hack to let us figure out what a connection's async thread is. If we * were MOZILLA_INTERNAL_API and linked as such we could just include * mozStorageConnection.h and just ask Connection directly. But that turns out * poorly. * * When the thread a mutex is invoked on isn't watched_thread we save it to this * variable. */ PRThread *last_non_watched_thread = NULL; /** * Set a flag if the mutex is used on the thread we are watching, but always * call the real mutex function. */ extern "C" void wrapped_MutexEnter(sqlite3_mutex *mutex) { PRThread *curThread = ::PR_GetCurrentThread(); if (curThread == watched_thread) mutex_used_on_watched_thread = true; else last_non_watched_thread = curThread; orig_mutex_methods.xMutexEnter(mutex); } extern "C" int wrapped_MutexTry(sqlite3_mutex *mutex) { if (::PR_GetCurrentThread() == watched_thread) mutex_used_on_watched_thread = true; return orig_mutex_methods.xMutexTry(mutex); } #define do_check_ok(aInvoc) do_check_true((aInvoc) == SQLITE_OK) void hook_sqlite_mutex() { // We need to initialize and teardown SQLite to get it to set up the // default mutex handlers for us so we can steal them and wrap them. do_check_ok(sqlite3_initialize()); do_check_ok(sqlite3_shutdown()); do_check_ok(::sqlite3_config(SQLITE_CONFIG_GETMUTEX, &orig_mutex_methods)); do_check_ok(::sqlite3_config(SQLITE_CONFIG_GETMUTEX, &wrapped_mutex_methods)); wrapped_mutex_methods.xMutexEnter = wrapped_MutexEnter; wrapped_mutex_methods.xMutexTry = wrapped_MutexTry; do_check_ok(::sqlite3_config(SQLITE_CONFIG_MUTEX, &wrapped_mutex_methods)); } /** * Call to clear the watch state and to set the watching against this thread. * * Check |mutex_used_on_watched_thread| to see if the mutex has fired since * this method was last called. Since we're talking about the current thread, * there are no race issues to be concerned about */ void watch_for_mutex_use_on_this_thread() { watched_thread = ::PR_GetCurrentThread(); mutex_used_on_watched_thread = false; } //////////////////////////////////////////////////////////////////////////////// //// Thread Wedgers /** * A runnable that blocks until code on another thread invokes its unwedge * method. By dispatching this to a thread you can ensure that no subsequent * runnables dispatched to the thread will execute until you invoke unwedge. * * The wedger is self-dispatching, just construct it with its target. */ class ThreadWedger : public nsRunnable { public: ThreadWedger(nsIEventTarget *aTarget) : mReentrantMonitor("thread wedger") , unwedged(false) { aTarget->Dispatch(this, aTarget->NS_DISPATCH_NORMAL); } NS_IMETHOD Run() { ReentrantMonitorAutoEnter automon(mReentrantMonitor); if (!unwedged) automon.Wait(); return NS_OK; } void unwedge() { ReentrantMonitorAutoEnter automon(mReentrantMonitor); unwedged = true; automon.Notify(); } private: ReentrantMonitor mReentrantMonitor; bool unwedged; }; //////////////////////////////////////////////////////////////////////////////// //// Async Helpers /** * A horrible hack to figure out what the connection's async thread is. By * creating a statement and async dispatching we can tell from the mutex who * is the async thread, PRThread style. Then we map that to an nsIThread. */ already_AddRefed get_conn_async_thread(mozIStorageConnection *db) { // Make sure we are tracking the current thread as the watched thread watch_for_mutex_use_on_this_thread(); // - statement with nothing to bind nsCOMPtr stmt; db->CreateAsyncStatement( NS_LITERAL_CSTRING("SELECT 1"), getter_AddRefs(stmt)); blocking_async_execute(stmt); stmt->Finalize(); nsCOMPtr threadMan = do_GetService("@mozilla.org/thread-manager;1"); nsCOMPtr asyncThread; threadMan->GetThreadFromPRThread(last_non_watched_thread, getter_AddRefs(asyncThread)); // Additionally, check that the thread we get as the background thread is the // same one as the one we report from getInterface. nsCOMPtr target = do_GetInterface(db); nsCOMPtr allegedAsyncThread = do_QueryInterface(target); PRThread *allegedPRThread; (void)allegedAsyncThread->GetPRThread(&allegedPRThread); do_check_eq(allegedPRThread, last_non_watched_thread); return asyncThread.forget(); } //////////////////////////////////////////////////////////////////////////////// //// Tests void test_TrueAsyncStatement() { // (only the first test needs to call this) hook_sqlite_mutex(); nsCOMPtr db(getMemoryDatabase()); // Start watching for forbidden mutex usage. watch_for_mutex_use_on_this_thread(); // - statement with nothing to bind nsCOMPtr stmt; db->CreateAsyncStatement( NS_LITERAL_CSTRING("CREATE TABLE test (id INTEGER PRIMARY KEY)"), getter_AddRefs(stmt) ); blocking_async_execute(stmt); stmt->Finalize(); do_check_false(mutex_used_on_watched_thread); // - statement with something to bind ordinally db->CreateAsyncStatement( NS_LITERAL_CSTRING("INSERT INTO test (id) VALUES (?)"), getter_AddRefs(stmt) ); stmt->BindInt32ByIndex(0, 1); blocking_async_execute(stmt); stmt->Finalize(); do_check_false(mutex_used_on_watched_thread); // - statement with something to bind by name db->CreateAsyncStatement( NS_LITERAL_CSTRING("INSERT INTO test (id) VALUES (:id)"), getter_AddRefs(stmt) ); nsCOMPtr paramsArray; stmt->NewBindingParamsArray(getter_AddRefs(paramsArray)); nsCOMPtr params; paramsArray->NewBindingParams(getter_AddRefs(params)); params->BindInt32ByName(NS_LITERAL_CSTRING("id"), 2); paramsArray->AddParams(params); params = nullptr; stmt->BindParameters(paramsArray); paramsArray = nullptr; blocking_async_execute(stmt); stmt->Finalize(); do_check_false(mutex_used_on_watched_thread); // - now, make sure creating a sync statement does trigger our guard. // (If this doesn't happen, our test is bunk and it's important to know that.) nsCOMPtr syncStmt; db->CreateStatement(NS_LITERAL_CSTRING("SELECT * FROM test"), getter_AddRefs(syncStmt)); syncStmt->Finalize(); do_check_true(mutex_used_on_watched_thread); blocking_async_close(db); } /** * Test that cancellation before a statement is run successfully stops the * statement from executing. */ void test_AsyncCancellation() { nsCOMPtr db(getMemoryDatabase()); // -- wedge the thread nsCOMPtr target(get_conn_async_thread(db)); do_check_true(target); nsRefPtr wedger (new ThreadWedger(target)); // -- create statements and cancel them // - async nsCOMPtr asyncStmt; db->CreateAsyncStatement( NS_LITERAL_CSTRING("CREATE TABLE asyncTable (id INTEGER PRIMARY KEY)"), getter_AddRefs(asyncStmt) ); nsRefPtr asyncSpin(new AsyncStatementSpinner()); nsCOMPtr asyncPend; (void)asyncStmt->ExecuteAsync(asyncSpin, getter_AddRefs(asyncPend)); do_check_true(asyncPend); asyncPend->Cancel(); // - sync nsCOMPtr syncStmt; db->CreateStatement( NS_LITERAL_CSTRING("CREATE TABLE syncTable (id INTEGER PRIMARY KEY)"), getter_AddRefs(syncStmt) ); nsRefPtr syncSpin(new AsyncStatementSpinner()); nsCOMPtr syncPend; (void)syncStmt->ExecuteAsync(syncSpin, getter_AddRefs(syncPend)); do_check_true(syncPend); syncPend->Cancel(); // -- unwedge the async thread wedger->unwedge(); // -- verify that both statements report they were canceled asyncSpin->SpinUntilCompleted(); do_check_true(asyncSpin->completionReason == mozIStorageStatementCallback::REASON_CANCELED); syncSpin->SpinUntilCompleted(); do_check_true(syncSpin->completionReason == mozIStorageStatementCallback::REASON_CANCELED); // -- verify that neither statement constructed their tables nsresult rv; bool exists; rv = db->TableExists(NS_LITERAL_CSTRING("asyncTable"), &exists); do_check_true(rv == NS_OK); do_check_false(exists); rv = db->TableExists(NS_LITERAL_CSTRING("syncTable"), &exists); do_check_true(rv == NS_OK); do_check_false(exists); // -- cleanup asyncStmt->Finalize(); syncStmt->Finalize(); blocking_async_close(db); } /** * Test that the destructor for an asynchronous statement which has a * sqlite3_stmt will dispatch that statement to the async thread for * finalization rather than trying to finalize it on the main thread * (and thereby running afoul of our mutex use detector). */ void test_AsyncDestructorFinalizesOnAsyncThread() { // test_TrueAsyncStatement called hook_sqlite_mutex() for us nsCOMPtr db(getMemoryDatabase()); watch_for_mutex_use_on_this_thread(); // -- create an async statement nsCOMPtr stmt; db->CreateAsyncStatement( NS_LITERAL_CSTRING("CREATE TABLE test (id INTEGER PRIMARY KEY)"), getter_AddRefs(stmt) ); // -- execute it so it gets a sqlite3_stmt that needs to be finalized blocking_async_execute(stmt); do_check_false(mutex_used_on_watched_thread); // -- forget our reference stmt = nullptr; // -- verify the mutex was not touched do_check_false(mutex_used_on_watched_thread); // -- make sure the statement actually gets finalized / cleanup // the close will assert if we failed to finalize! blocking_async_close(db); } void (*gTests[])(void) = { // this test must be first because it hooks the mutex mechanics test_TrueAsyncStatement, test_AsyncCancellation, test_AsyncDestructorFinalizesOnAsyncThread }; const char *file = __FILE__; #define TEST_NAME "true async statement" #define TEST_FILE file #include "storage_test_harness_tail.h"