genode/repos/base-foc/include/foc/native_capability.h
Norman Feske eba9c15746 Follow practices suggested by "Effective C++"
The patch adjust the code of the base, base-<kernel>, and os repository.
To adapt existing components to fix violations of the best practices
suggested by "Effective C++" as reported by the -Weffc++ compiler
argument. The changes follow the patterns outlined below:

* A class with virtual functions can no longer publicly inherit base
  classed without a vtable. The inherited object may either be moved
  to a member variable, or inherited privately. The latter would be
  used for classes that inherit 'List::Element' or 'Avl_node'. In order
  to enable the 'List' and 'Avl_tree' to access the meta data, the
  'List' must become a friend.

* Instead of adding a virtual destructor to abstract base classes,
  we inherit the new 'Interface' class, which contains a virtual
  destructor. This way, single-line abstract base classes can stay
  as compact as they are now. The 'Interface' utility resides in
  base/include/util/interface.h.

* With the new warnings enabled, all member variables must be explicitly
  initialized. Basic types may be initialized with '='. All other types
  are initialized with braces '{ ... }' or as class initializers. If
  basic types and non-basic types appear in a row, it is nice to only
  use the brace syntax (also for basic types) and align the braces.

* If a class contains pointers as members, it must now also provide a
  copy constructor and assignment operator. In the most cases, one
  would make them private, effectively disallowing the objects to be
  copied. Unfortunately, this warning cannot be fixed be inheriting
  our existing 'Noncopyable' class (the compiler fails to detect that
  the inheriting class cannot be copied and still gives the error).
  For now, we have to manually add declarations for both the copy
  constructor and assignment operator as private class members. Those
  declarations should be prepended with a comment like this:

        /*
         * Noncopyable
         */
        Thread(Thread const &);
        Thread &operator = (Thread const &);

  In the future, we should revisit these places and try to replace
  the pointers with references. In the presence of at least one
  reference member, the compiler would no longer implicitly generate
  a copy constructor. So we could remove the manual declaration.

Issue #465
2018-01-17 12:14:35 +01:00

81 lines
2.4 KiB
C++

/*
* \brief Kernel-specific capability helpers and definitions
* \author Norman Feske
* \date 2016-06-01
*/
/*
* Copyright (C) 2016-2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
#ifndef _INCLUDE__FOC__NATIVE_CAPABILITY_H_
#define _INCLUDE__FOC__NATIVE_CAPABILITY_H_
namespace Fiasco {
#include <l4/sys/consts.h>
#include <l4/sys/types.h>
#include <l4/sys/utcb.h>
#include <l4/sys/task.h>
/*********************************************
** Capability selectors controlled by core **
*********************************************/
/* use the same task cap selector like L4Re for compatibility in L4Linux */
static constexpr l4_cap_idx_t TASK_CAP = L4_BASE_TASK_CAP;
static constexpr l4_cap_idx_t DEBUG_CAP = L4_BASE_DEBUGGER_CAP;
/*
* To not clash with other L4Re cap selector constants (e.g.: L4Linux)
* leave the following selectors (2-8) empty
*/
/* cap to parent session */
static constexpr l4_cap_idx_t PARENT_CAP = 0xbUL << L4_CAP_SHIFT;
/*
* Each thread has a designated slot in the core controlled cap
* selector area, where its ipc gate capability (for server threads),
* its irq capability (for locks), and the capability to its pager
* gate are stored
*/
/* offset to thread area */
static constexpr l4_cap_idx_t THREAD_AREA_BASE = 0xcUL << L4_CAP_SHIFT;
/* size of one thread slot */
static constexpr l4_cap_idx_t THREAD_AREA_SLOT = 0x3UL << L4_CAP_SHIFT;
/* offset to the ipc gate cap selector in the slot */
static constexpr l4_cap_idx_t THREAD_GATE_CAP = 0;
/* offset to the pager cap selector in the slot */
static constexpr l4_cap_idx_t THREAD_PAGER_CAP = 0x1UL << L4_CAP_SHIFT;
/* offset to the irq cap selector in the slot */
static constexpr l4_cap_idx_t THREAD_IRQ_CAP = 0x2UL << L4_CAP_SHIFT;
/* shortcut to the main thread's gate cap */
static constexpr l4_cap_idx_t MAIN_THREAD_CAP = THREAD_AREA_BASE
+ THREAD_GATE_CAP;
/*********************************************************
** Capability seclectors controlled by the task itself **
*********************************************************/
static constexpr l4_cap_idx_t USER_BASE_CAP = 0x200UL << L4_CAP_SHIFT;
struct Capability
{
static bool valid(l4_cap_idx_t idx) {
return !(idx & L4_INVALID_CAP_BIT) && idx != 0; }
};
}
#endif /* _INCLUDE__FOC__NATIVE_CAPABILITY_H_ */