/*

 * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#include "precompiled.hpp"

#include "runtime/interfaceSupport.inline.hpp"

#include "classfile/symbolTable.hpp"

#include "threadHelper.inline.hpp"

#include "unittest.hpp"

TEST_VM(SymbolTable, temp_new_symbol) {

  // Assert messages assume these symbols are unique, and the refcounts start at

  // one, but code does not rely on this.

  JavaThread* THREAD = JavaThread::current();

  // the thread should be in vm to use locks

  ThreadInVMfromNative ThreadInVMfromNative(THREAD);

  Symbol* abc = SymbolTable::new_symbol("abc", CATCH);

  int abccount = abc->refcount();

  TempNewSymbol ss = abc;

  ASSERT_EQ(ss->refcount(), abccount) << "only one abc";

  ASSERT_EQ(ss->refcount(), abc->refcount()) << "should match TempNewSymbol";

  Symbol* efg = SymbolTable::new_symbol("efg", CATCH);

  Symbol* hij = SymbolTable::new_symbol("hij", CATCH);

  int efgcount = efg->refcount();

  int hijcount = hij->refcount();

  TempNewSymbol s1 = efg;

  TempNewSymbol s2 = hij;

  ASSERT_EQ(s1->refcount(), efgcount) << "one efg";

  ASSERT_EQ(s2->refcount(), hijcount) << "one hij";

  // Assignment operator

  s1 = s2;

  ASSERT_EQ(hij->refcount(), hijcount + 1) << "should be two hij";

  ASSERT_EQ(efg->refcount(), efgcount - 1) << "should be no efg";

  s1 = ss; // s1 is abc

  ASSERT_EQ(s1->refcount(), abccount + 1) << "should be two abc (s1 and ss)";

  ASSERT_EQ(hij->refcount(), hijcount) << "should only have one hij now (s2)";

  s1 = s1; // self assignment

  ASSERT_EQ(s1->refcount(), abccount + 1) << "should still be two abc (s1 and ss)";

  TempNewSymbol s3;

  Symbol* klm = SymbolTable::new_symbol("klm", CATCH);

  int klmcount = klm->refcount();

  s3 = klm; // assignment

  ASSERT_EQ(s3->refcount(), klmcount) << "only one klm now";

  Symbol* xyz = SymbolTable::new_symbol("xyz", CATCH);

  int xyzcount = xyz->refcount();

  { // inner scope

    TempNewSymbol s_inner = xyz;

  }

  ASSERT_EQ(xyz->refcount(), xyzcount - 1)

          << "Should have been decremented by dtor in inner scope";

  // Test overflowing refcount making symbol permanent

  Symbol* bigsym = SymbolTable::new_symbol("bigsym", CATCH);

  for (int i = 0; i < PERM_REFCOUNT + 100; i++) {

    bigsym->increment_refcount();

  }

  ASSERT_EQ(bigsym->refcount(), PERM_REFCOUNT) << "should not have overflowed";

  // Test that PERM_REFCOUNT is sticky

  for (int i = 0; i < 10; i++) {

    bigsym->decrement_refcount();

  }

  ASSERT_EQ(bigsym->refcount(), PERM_REFCOUNT) << "should be sticky";

}

// TODO: Make two threads one decrementing the refcount and the other trying to increment.

// try_increment_refcount should return false

#define SYM_NAME_LENGTH 30

static char symbol_name[SYM_NAME_LENGTH];

class SymbolThread : public JavaTestThread {

  public:

  SymbolThread(Semaphore* post) : JavaTestThread(post) {}

  virtual ~SymbolThread() {}

  void main_run() {

    Thread* THREAD = Thread::current();

    for (int i = 0; i < 1000; i++) {

      TempNewSymbol sym = SymbolTable::new_symbol(symbol_name, CATCH);

      // Create and destroy new symbol

      EXPECT_TRUE(sym->refcount() != 0) << "Symbol refcount unexpectedly zeroed";

    }

  }

};

#define SYM_TEST_THREAD_COUNT 5

class DriverSymbolThread : public JavaTestThread {

public:

  Semaphore _done;

  DriverSymbolThread(Semaphore* post) : JavaTestThread(post) { };

  virtual ~DriverSymbolThread(){}

  void main_run() {

    Semaphore done(0);

    Thread* THREAD = Thread::current();

    // Find a symbol where there will probably be only one instance.

    for (int i = 0; i < 100; i++) {

       os::snprintf(symbol_name, SYM_NAME_LENGTH, "some_symbol%d", i);

       TempNewSymbol ts = SymbolTable::new_symbol(symbol_name, CATCH);

       if (ts->refcount() == 1) {

         EXPECT_TRUE(ts->refcount() == 1) << "Symbol is just created";

         break;  // found a unique symbol

       }

    }

    SymbolThread* st[SYM_TEST_THREAD_COUNT];

    for (int i = 0; i < SYM_TEST_THREAD_COUNT; i++) {

      st[i] = new SymbolThread(&done);

      st[i]->doit();

    }

    for (int i = 0; i < SYM_TEST_THREAD_COUNT; i++) {

      done.wait();

    }

  }

};

TEST_VM(SymbolTable, test_symbol_refcount_parallel) {

  mt_test_doer<DriverSymbolThread>();

}