// vi:ft=cpp
/**
 * \file
 * \brief Common thread related definitions.
 */
/*
 * (c) 2008-2009 Adam Lackorzynski <adam@os.inf.tu-dresden.de>,
 *               Alexander Warg <warg@os.inf.tu-dresden.de>
 *     economic rights: Technische Universität Dresden (Germany)
 *
 * This file is part of TUD:OS and distributed under the terms of the
 * GNU General Public License 2.
 * Please see the COPYING-GPL-2 file for details.
 *
 * As a special exception, you may use this file as part of a free software
 * library without restriction.  Specifically, if other files instantiate
 * templates or use macros or inline functions from this file, or you compile
 * this file and link it with other files to produce an executable, this
 * file does not by itself cause the resulting executable to be covered by
 * the GNU General Public License.  This exception does not however
 * invalidate any other reasons why the executable file might be covered by
 * the GNU General Public License.
 */

#pragma once

#include <l4/sys/capability>
#include <l4/sys/thread.h>

namespace L4 {

/**
 * \ingroup l4_thread_api
 * \brief L4 kernel thread.
 *
 * <c>\#include <l4/sys/thread></c>
 */
class Thread : public Kobject_t<Thread, Kobject, L4_PROTO_THREAD>
{
  L4_KOBJECT(Thread)

public:
  /**
   * \copydoc l4_thread_ex_regs()
   * \note the \a thread argument is the implicit \a this pointer.
   */
  l4_msgtag_t ex_regs(l4_addr_t ip, l4_addr_t sp,
                      l4_umword_t flags,
                      l4_utcb_t *utcb = l4_utcb()) throw()
  { return l4_thread_ex_regs_u(cap(), ip, sp, flags, utcb); }

  /**
   * \copydoc l4_thread_ex_regs_ret()
   * \note the \a thread argument is the implicit \a this pointer.
   */
  l4_msgtag_t ex_regs(l4_addr_t *ip, l4_addr_t *sp,
                      l4_umword_t *flags,
                      l4_utcb_t *utcb = l4_utcb()) throw()
  { return l4_thread_ex_regs_ret_u(cap(), ip, sp, flags, utcb); }


  /**
   * \brief Thread attributes used for control_commit().
   *
   * This class is responsible for initalizing various attributes of a
   * thread in a UTCB for the control_commit() method.
   *
   * \see \ref l4_thread_control_api for some more details.
   */
  class Attr
  {
  private:
     friend class L4::Thread;
     l4_utcb_t *_u;

   public:
     /**
      * \brief Create a thread-attribute object with the given UTCB.
      * \param utcb the UTCB to use for the later L4::Thread::control_commit()
      *             function. Usually this is the UTCB of the calling thread.
      */
     explicit Attr(l4_utcb_t *utcb = l4_utcb()) throw() : _u(utcb)
     { l4_thread_control_start_u(utcb); }

     /**
      * \brief Set the pager capability selector.
      * \param pager the capability selector that shall be used for page-fault
      *              messages. This capability selector must be valid within
      *              the task the thread is bound to.
      */
     void pager(Cap<void> const &pager) throw()
     { l4_thread_control_pager_u(pager.cap(), _u); }

     /**
      * \brief Get the capability selector used for page-fault messages.
      * \return the capability selector used to send page-fault messages. The
      *         selector is valid in the task the thread is bound to.
      */
     Cap<void> pager() throw()
     { return Cap<void>(l4_utcb_mr_u(_u)->mr[1]); }

     /**
      * \brief Set the exception-handler capability selector.
      * \param pager the capability selector that shall be used for exception
      *              messages. This capability selector must be
      *              valid within the task the thread is bound to.
      */
     void exc_handler(Cap<void> const &exc_handler) throw()
     { l4_thread_control_exc_handler_u(exc_handler.cap(), _u); }

     /**
      * \brief Get the capability selector used for exception messages.
      * \return the capability selector used to send exception messages. The
      *         selector is valid in the task the thread is bound to.
      */
     Cap<void> exc_handler() throw()
     { return Cap<void>(l4_utcb_mr_u(_u)->mr[2]); }

     /**
      * \brief Set the scheduler capability selector.
      * \param pager the capability selector that shall be used for scheduling
      *              messages. This capability selector must be
      *              valid within the task the thread is bound to.
      */
     void scheduler(Cap<void> const &scheduler) throw()
     { l4_thread_control_scheduler_u(scheduler.cap(), _u); }

     /**
      * \brief Get the capability selector used for scheduling messages.
      * \return the capability selector used to send scheduling messages. The
      *         selector is valid in the task the thread is bound to.
      */
     Cap<void> scheduler() throw()
     { return Cap<void>(l4_utcb_mr_u(_u)->mr[2]); }

     /**
      * \brief Bind the thread to a task.
      * \param thread_utcb the UTCB address of the thread within the task
      *                    specified by \a task.
      * \param task        the capability selector for the task the thread
      *                    shall be bound to.
      *
      * Binding a thread to a task means that the thread shall afterwards
      * execute in the given task. To actually start execution you need
      * to use L4::Thread::ex_regs().
      */
     void bind(l4_utcb_t *thread_utcb, Cap<Task> const &task) throw()
     { l4_thread_control_bind_u(thread_utcb, task.cap(), _u); }

     /**
      * \brief Set the thread to alien mode.
      */
     void alien(int on) throw()
     { l4_thread_control_alien_u(_u, on); }

     /**
      * \brief Allow host system calls on Fiasco-UX.
      * \pre Running on Fiasco-UX.
      */
     void ux_host_syscall(int on) throw()
     { l4_thread_control_ux_host_syscall_u(_u, on); }

   };

  /**
   * \brief Commit the given thread-attributes object.
   * \param attr the attribute object to commit to the thread.
   */
  l4_msgtag_t control(Attr const &attr) throw()
  { return l4_thread_control_commit_u(cap(), attr._u); }

  /**
   * \brief Switch execution to this thread.
   * \param utcb the UTCB of the current thread.
   *
   * \note The current time slice is inherited to this thread.
   */
  l4_msgtag_t switch_to(l4_utcb_t *utcb = l4_utcb()) throw()
  { return l4_thread_switch_u(cap(), utcb); }

  /**
   * \brief Get consumed timed of thread in ns.
   * \param utcb the UTCB of the current thread.
   *
   * The consumed time is return as l4_kernel_clock_t at UTCB message
   * register 0.
   */
  l4_msgtag_t stats_time(l4_utcb_t *utcb = l4_utcb()) throw()
  { return l4_thread_stats_time_u(cap(), utcb); }

  /**
   * \brief vCPU resume, start.
   *
   * \see l4_thread_vcpu_resume_start
   */
  l4_msgtag_t vcpu_resume_start(l4_utcb_t *utcb = l4_utcb()) throw()
  { return l4_thread_vcpu_resume_start_u(utcb); }

  /**
   * \brief vCPU resume, commit.
   *
   * \see l4_thread_vcpu_resume_commit
   */
  l4_msgtag_t vcpu_resume_commit(l4_msgtag_t tag,
                                 l4_utcb_t *utcb = l4_utcb()) throw()
  { return l4_thread_vcpu_resume_commit_u(cap(), tag, utcb); }

   /**
    * \copydoc l4_thread_vcpu_control()
    */
   l4_msgtag_t vcpu_control(l4_addr_t vcpu_state, l4_utcb_t *utcb = l4_utcb())
     throw()
   { return l4_thread_vcpu_control_u(cap(), vcpu_state, utcb); }

   /**
    * \copydoc l4_thread_vcpu_control_exit()
    */
   l4_msgtag_t vcpu_control_ext(l4_addr_t ext_vcpu_state,
                                l4_utcb_t *utcb = l4_utcb()) throw()
   { return l4_thread_vcpu_control_ext_u(cap(), ext_vcpu_state, utcb); }

  /**
   * \brief Register an IRQ that will trigger upon deletion events.
   *
   * \see l4_thread_register_del_irq
   */
  l4_msgtag_t register_del_irq(Cap<Irq> irq, l4_utcb_t *u = l4_utcb()) throw()
  { return l4_thread_register_del_irq_u(cap(), irq.cap(), u); }

  /**
   * \brief Wrapper class for modifying senders.
   *
   * Use the add() function to add modification rules, and use
   * modify_senders() to commit. Do not use the UTCB inbetween as it is
   * used by add() and modify_senders().
   */
  class Modify_senders
  {
  private:
    friend class Thread;
    l4_utcb_t *utcb;
    unsigned cnt;

  public:
    explicit Modify_senders(l4_utcb_t *u = l4_utcb()) throw()
    : utcb(u), cnt(1)
    {
      l4_utcb_mr_u(utcb)->mr[0] = L4_THREAD_MODIFY_SENDER;
    }

    /**
     * \brief Add a rule.
     *
     * \param match_mask Bitmask of bits to match the label.
     * \param match      Bitmask that must be equal to the label after applying
     *                   match_mask.
     * \param del_bits   Bits to be deleted from the label.
     * \param add_bits   Bits to be added to the label.
     *
     * \return 0 on sucess, <0 on error
     *
     * Only the first match is applied.
     *
     * \see l4_thread_modify_sender_add()
     */
    int add(l4_umword_t match_mask, l4_umword_t match,
            l4_umword_t del_bits, l4_umword_t add_bits) throw()
    {
      l4_msg_regs_t *m = l4_utcb_mr_u(utcb);
      if (cnt >= L4_UTCB_GENERIC_DATA_SIZE - 4)
        return -L4_ENOMEM;
      m->mr[cnt++] = match_mask;
      m->mr[cnt++] = match;
      m->mr[cnt++] = del_bits;
      m->mr[cnt++] = add_bits;
      return 0;
    }
  };

  /**
   * \brief Apply sender modifiction rules.
   *
   * \param todo   Prepared sender modification rules.
   *
   * \return System call return tag.
   */
  l4_msgtag_t modify_senders(Modify_senders const &todo) throw()
  {
    return l4_ipc_call(cap(), todo.utcb, l4_msgtag(L4_PROTO_THREAD, todo.cnt, 0, 0), L4_IPC_NEVER);
  }
};
}