/*

 * Copyright (c) 2015, 2016, 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

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 */

#ifndef SHARE_VM_RUNTIME_JVMFLAGCONSTRAINTLIST_HPP

#define SHARE_VM_RUNTIME_JVMFLAGCONSTRAINTLIST_HPP

#include "runtime/flags/jvmFlag.hpp"

#include "utilities/growableArray.hpp"

/*

 * Here we have a mechanism for extracting constraints (as custom functions) for flags,

 * which otherwise can not be expressed via simple range check, specified in flag macro tables.

 *

 * An example of a constraint is "flag1 < flag2" where both flag1 and flag2 can change.

 *

 * See runtime "runtime/flags/jvmFlagConstraintsCompiler.hpp",

 * "runtime/flags/jvmFlagConstraintsGC.hpp" and

 * "runtime/flags/jvmFlagConstraintsRuntime.hpp" for the functions themselves.

 */

typedef JVMFlag::Error (*JVMFlagConstraintFunc_bool)(bool value, bool verbose);

typedef JVMFlag::Error (*JVMFlagConstraintFunc_int)(int value, bool verbose);

typedef JVMFlag::Error (*JVMFlagConstraintFunc_intx)(intx value, bool verbose);

typedef JVMFlag::Error (*JVMFlagConstraintFunc_uint)(uint value, bool verbose);

typedef JVMFlag::Error (*JVMFlagConstraintFunc_uintx)(uintx value, bool verbose);

typedef JVMFlag::Error (*JVMFlagConstraintFunc_uint64_t)(uint64_t value, bool verbose);

typedef JVMFlag::Error (*JVMFlagConstraintFunc_size_t)(size_t value, bool verbose);

typedef JVMFlag::Error (*JVMFlagConstraintFunc_double)(double value, bool verbose);

class JVMFlagConstraint : public CHeapObj<mtArguments> {

public:

  // During VM initialization, constraint validation will be done order of ConstraintType.

  enum ConstraintType {

    // Will be validated during argument processing (Arguments::parse_argument).

    AtParse         = 0,

    // Will be validated inside Threads::create_vm(), right after Arguments::apply_ergo().

    AfterErgo       = 1,

    // Will be validated inside universe_init(), right after Metaspace::global_initialize().

    AfterMemoryInit = 2

  };

private:

  const char* _name;

  ConstraintType _validate_type;

public:

  // the "name" argument must be a string literal

  JVMFlagConstraint(const char* name, ConstraintType type) { _name=name; _validate_type=type; };

  ~JVMFlagConstraint() {};

  const char* name() const { return _name; }

  ConstraintType type() const { return _validate_type; }

  virtual JVMFlag::Error apply(bool verbose = true) { ShouldNotReachHere(); return JVMFlag::ERR_OTHER; };

  virtual JVMFlag::Error apply_bool(bool value, bool verbose = true) { ShouldNotReachHere(); return JVMFlag::ERR_OTHER; };

  virtual JVMFlag::Error apply_int(int value, bool verbose = true) { ShouldNotReachHere(); return JVMFlag::ERR_OTHER; };

  virtual JVMFlag::Error apply_intx(intx value, bool verbose = true) { ShouldNotReachHere(); return JVMFlag::ERR_OTHER; };

  virtual JVMFlag::Error apply_uint(uint value, bool verbose = true) { ShouldNotReachHere(); return JVMFlag::ERR_OTHER; };

  virtual JVMFlag::Error apply_uintx(uintx value, bool verbose = true) { ShouldNotReachHere(); return JVMFlag::ERR_OTHER; };

  virtual JVMFlag::Error apply_uint64_t(uint64_t value, bool verbose = true) { ShouldNotReachHere(); return JVMFlag::ERR_OTHER; };

  virtual JVMFlag::Error apply_size_t(size_t value, bool verbose = true) { ShouldNotReachHere(); return JVMFlag::ERR_OTHER; };

  virtual JVMFlag::Error apply_double(double value, bool verbose = true) { ShouldNotReachHere(); return JVMFlag::ERR_OTHER; };

};

class JVMFlagConstraintList : public AllStatic {

private:

  static GrowableArray<JVMFlagConstraint*>* _constraints;

  // Latest constraint validation type.

  static JVMFlagConstraint::ConstraintType _validating_type;

public:

  static void init();

  static int length() { return (_constraints != NULL) ? _constraints->length() : 0; }

  static JVMFlagConstraint* at(int i) { return (_constraints != NULL) ? _constraints->at(i) : NULL; }

  static JVMFlagConstraint* find(const char* name);

  static JVMFlagConstraint* find_if_needs_check(const char* name);

  static void add(JVMFlagConstraint* constraint) { _constraints->append(constraint); }

  // True if 'AfterErgo' or later constraint functions are validated.

  static bool validated_after_ergo() { return _validating_type >= JVMFlagConstraint::AfterErgo; };

  static bool check_constraints(JVMFlagConstraint::ConstraintType type);

};

#endif /* SHARE_VM_RUNTIME_JVMFLAGCONSTRAINTLIST_HPP */