messages.F90

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!! Copyright (C) 2002-2021 M. Marques, A. Castro, A. Rubio, G. Bertsch, X. Andrade,
!! Copyright (C) 2021 M. Lueders
!!
!! This program is free software; you can redistribute it and/or modify
!! it under the terms of the GNU General Public License as published by
!! the Free Software Foundation; either version 2, or (at your option)
!! any later version.
!!
!! This program 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 for more details.
!!
!! You should have received a copy of the GNU General Public License
!! along with this program; if not, write to the Free Software
!! Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
!! 02110-1301, USA.
!!
 
#include "global.h"
 
module messages_oct_m
  use debug_oct_m
  use global_oct_m
  use io_oct_m
  use loct_oct_m
  use mpi_oct_m
  use namespace_oct_m
  use parser_oct_m
  use string_oct_m
  use sihash_oct_m
  use sphash_oct_m
  use unit_oct_m
  use varinfo_oct_m
 
  implicit none
 
  private
 
  public ::                     &
    messages_init,              &
    messages_end,               &
    messages_fatal,             &
    messages_warning,           &
    messages_info,              &
    messages_switch_status,     &
    print_date,                 &
    time_sum,                   &
    alloc_error,                &
    dealloc_error,              &
    messages_input_error,       &
    messages_print_with_emphasis,      &
    messages_print_var_info,    &
    messages_print_var_option,  &
    messages_print_var_value,   &
    messages_obsolete_variable, &
    messages_variable_is_block, &
    messages_experimental,      &
    messages_not_implemented,   &
    messages_new_line,          &
    messages_write,             &
    messages_dump_stack,        &
    messages_update_mpi_grp
 
 
  integer, parameter :: max_lines = 20
  character(len=256), dimension(max_lines), public :: message
  character(len=68),      parameter, public :: hyphens = &
    '--------------------------------------------------------------------'
  character(len=69),      parameter, public :: shyphens = '*'//hyphens
 
  character(len=512), private :: msg
  integer, parameter, private :: SLEEPYTIME_ALL = 1, sleepytime_nonwriters = 60 
  character(len=64),  private :: oct_status = 'undefined'
 
  type(sihash_t),     private :: namespace_unit
  type(sphash_t),     private :: namespace_mpi_grp
  character(len=256), private :: msg_dir = 'exec'
 
  ! ---------------------------------------------------------
  ! ---------------------------------------------------------
  interface messages_print_var_value
    module procedure messages_print_var_valuei
    module procedure messages_print_var_values
    module procedure messages_print_var_valuer
    module procedure messages_print_var_valuel
    module procedure messages_print_var_valuear
  end interface messages_print_var_value
 
  interface messages_write
    module procedure messages_write_float
    module procedure messages_write_integer
    module procedure messages_write_integer8
    module procedure messages_write_str
    module procedure messages_write_logical
  end interface messages_write
 
 
  interface  messages_print_var_option
    module procedure messages_print_var_option_4
    module procedure messages_print_var_option_8
  end interface messages_print_var_option
 
  integer :: warnings
  integer :: experimentals
  integer :: current_line
 
  interface
    subroutine get_signal_description(signum, signame)
      implicit none
      integer, intent(in) :: signum
      character(len=*), intent(out) :: signame
    end subroutine get_signal_description
 
    subroutine trap_segfault()
      implicit none
    end subroutine trap_segfault
  end interface
 
 
contains
 
  ! ---------------------------------------------------------
  subroutine messages_init(output_dir)
    character(len=*), intent(in), optional :: output_dir
 
    logical :: trap_signals
 
    if (present(output_dir)) then
      msg_dir = trim(output_dir)
    endif
 
    call sihash_init(namespace_unit)
    call sphash_init(namespace_mpi_grp)
 
    call messages_obsolete_variable(global_namespace, 'DevelVersion', 'ExperimentalFeatures')
 
    !%Variable ExperimentalFeatures
    !%Type logical
    !%Default no
    !%Section Execution::Debug
    !%Description
    !% If true, allows the use of certain parts of the code that are
    !% still under development and are not suitable for production
    !% runs. This should not be used unless you know what you are doing.
    !% See details on
    !% <a href=https://www.octopus-code.org/documentation/main/variables/execution/debug/experimentalfeatures>wiki page</a>.
    !%End
    call parse_variable(global_namespace, 'ExperimentalFeatures', .false., conf%devel_version)
 
    call messages_obsolete_variable(global_namespace, 'DebugLevel', 'Debug')
 
    call debug_init(debug, global_namespace)
 
    warnings = 0
    experimentals = 0
 
    !%Variable DebugTrapSignals
    !%Type logical
    !%Default yes
    !%Section Execution::Debug
    !%Description
    !% If true, trap signals to handle them in octopus itself and
    !% print a custom backtrace. If false, do not trap signals; then,
    !% core dumps can be produced or gdb can be used to stop at the
    !% point a signal was produced (e.g. a segmentation fault).
    !%End
    call parse_variable(global_namespace, 'DebugTrapSignals', .true., trap_signals)
 
    if (trap_signals) call trap_segfault()
 
    call messages_reset_lines()
 
  end subroutine messages_init
 
  ! ---------------------------------------------------------
  subroutine messages_end()
 
    type(sihash_iterator_t) :: it
    integer :: iu
 
    if (mpi_grp_is_root(mpi_world)) then
 
      if (experimentals > 0 .or. warnings > 0) then
        message(1) = ''
        call messages_info(1)
      end if
 
 
      if (warnings > 0) then
        call messages_write('Octopus emitted ')
        call messages_write(warnings)
        if (warnings > 1) then
          call messages_write(' warnings.')
        else
          call messages_write(' warning.')
        end if
        call messages_info()
      end if
 
      if (experimentals > 0) then
        call messages_new_line()
        call messages_write('Octopus used ')
        call messages_write(experimentals)
        if (experimentals > 1) then
          call messages_write(' experimental features:')
        else
          call messages_write(' experimental feature:')
        end if
        call messages_new_line()
        call messages_new_line()
        call messages_write('  Since you used one or more experimental features, results are likely')
        call messages_new_line()
        call messages_write('  wrong and should not  be considered as valid scientific data.  Check')
        call messages_new_line()
        call messages_new_line()
        call messages_write('  https://www.octopus-code.org/documentation/main/variables/execution/debug/experimentalfeatures')
        call messages_new_line()
        call messages_new_line()
        call messages_write('  or contact the octopus developers for details.')
        call messages_new_line()
        call messages_info()
      end if
 
      open(unit = iunit_out, file = trim(msg_dir) // '/messages', action = 'write')
      write(iunit_out, '(a, i9)') "warnings          = ", warnings
      write(iunit_out, '(a, i9)') "experimental      = ", experimentals
      close(iunit_out)
 
    end if
 
    call it%start(namespace_unit)
    do while(it%has_next())
      iu = it%get_next()
      if (iu /= stderr .and. iu /= stdout) call io_close(iu)
    end do
 
    call sphash_end(namespace_mpi_grp)
    call sihash_end(namespace_unit)
 
  end subroutine messages_end
 
  ! ---------------------------------------------------------
  integer function messages_get_unit(namespace) result(iunit)
    type(namespace_t), optional, intent(in) :: namespace
 
    logical :: found
 
    if (present(namespace)) then
 
      if (namespace%get()=="") then
        iunit = stdout
        return
      end if
 
      iunit = sihash_lookup( namespace_unit, namespace%get(), found)
 
      if (.not. found) then
        call io_mkdir('', namespace)
        iunit = io_open("log", namespace=namespace, action="write")
 
        if(iunit > 0) then
          call sihash_insert(namespace_unit, namespace%get(), iunit)
        else
          write(message(1),*) "Cannot get unit for namespace ", namespace%get()
          call messages_fatal(1)
        end if
      endif
 
    else
      iunit = stdout
    end if
 
  end function messages_get_unit
 
  ! ---------------------------------------------------------
  subroutine messages_update_mpi_grp(namespace, mpigrp)
    type(namespace_t),         intent(in) :: namespace
    type(mpi_grp_t),   target, intent(in) :: mpigrp
 
    ! messages not initialised
    assert(namespace_mpi_grp%is_associated())
    call sphash_insert(namespace_mpi_grp, namespace%get(), mpigrp, clone=.true.)
 
  end subroutine messages_update_mpi_grp
 
  ! ---------------------------------------------------------
  function messages_get_mpi_grp(namespace) result(grp)
    type(namespace_t), optional, intent(in)  :: namespace
    type(mpi_grp_t)   :: grp
 
    class(*), pointer :: value
    logical           :: found
 
    if (present(namespace)) then
      ! messages not initialised
      assert(namespace_mpi_grp%is_associated())
 
      value => sphash_lookup(namespace_mpi_grp, trim(namespace%get()), found)
 
      if (.not.found) then
        grp = mpi_world
        return
      endif
 
      select type(value)
      type is (mpi_grp_t)
        grp = value
      class default
        write(message(1),*) "Cannot get mpi_grp for namespace ",namespace%get()
        call messages_fatal(1)
      end select
    else
      grp = mpi_world
    end if
 
  end function messages_get_mpi_grp
 
  ! ---------------------------------------------------------
  subroutine messages_fatal(no_lines, only_root_writes, namespace)
    integer,           optional, intent(in) :: no_lines
    logical,           optional, intent(in) :: only_root_writes
    type(namespace_t), optional, intent(in) :: namespace
 
    type(mpi_grp_t) :: msg_mpi_grp
    integer :: ii, no_lines_
    logical :: only_root_writes_, should_write
    integer, allocatable :: recv_buf(:)
    type(mpi_request), allocatable :: recv_req(:)
#ifdef HAVE_MPI
    integer, parameter :: fatal_tag = 32767
    logical :: received
    type(mpi_request) :: send_req
#endif
 
    no_lines_ = current_line
    if (present(no_lines)) no_lines_ = no_lines
 
    msg_mpi_grp = messages_get_mpi_grp(namespace)
 
    if (present(only_root_writes)) then
      should_write = mpi_grp_is_root(msg_mpi_grp) .or. (.not. only_root_writes)
      only_root_writes_ = only_root_writes
    else
      should_write = .true.
      only_root_writes_ = .false.
    end if
 
    ! This is to avoid all nodes reporting an error. The root node
    ! post a message reception to all nodes, the rest of the nodes
    ! send a message. If the message is received, the non-root nodes
    ! know that the root node will report the error, so they do not do
    ! anything.
 
    if (.not. only_root_writes_) then
      if (msg_mpi_grp%rank == 0) then
 
        allocate(recv_buf(1:mpi_world%size - 1))
        allocate(recv_req(1:mpi_world%size - 1))
        do ii = 1, mpi_world%size - 1
#ifdef HAVE_MPI
          call mpi_recv_init(recv_buf(ii), 1, mpi_integer, ii, fatal_tag, msg_mpi_grp%comm, recv_req(ii), mpi_err)
#endif
        end do
        deallocate(recv_buf)
        deallocate(recv_req)
 
      else
 
#ifdef HAVE_MPI
        call mpi_send_init(1, 1, mpi_integer, 0, fatal_tag, msg_mpi_grp%comm, send_req, mpi_err)
#endif
        !sleep for a second and check
        call loct_nanosleep(sleepytime_all, 0)
#ifdef HAVE_MPI
        call mpi_test(send_req, received, mpi_status_ignore, mpi_err)
#endif
        should_write = .false.
 
      end if
    end if
 
    ! Give a moment for all standard output hopefully to be printed
    call loct_nanosleep(sleepytime_all, 0)
 
    ! If we are not writing wait for the root node to get here and
    ! write the error message. If the root doesn`t get here, we all print the
    ! error messsage anyways and die. Otherwise, no message might be written.
    if (.not. should_write) call loct_nanosleep(sleepytime_nonwriters, 0)
 
    call messages_print_with_emphasis(msg="FATAL ERROR", iunit=stderr)
    write(msg, '(a)') '*** Fatal Error (description follows)'
    call flush_msg(msg, stderr)
 
    if (present(namespace)) then
      if (len_trim(namespace%get()) > 0) then
        write(msg, '(3a)') '* In namespace ', trim(namespace%get()), ':'
        call flush_msg(msg, stderr)
      end if
    end if
 
#ifdef HAVE_MPI
    if (.not. only_root_writes_ .or. .not. mpi_grp_is_root(msg_mpi_grp)) then
      call flush_msg(shyphens, stderr)
      write(msg, '(a,i4)') "* From node = ", msg_mpi_grp%rank
      call flush_msg(msg, stderr)
    end if
#endif
    call flush_msg(shyphens, stderr)
    do ii = 1, no_lines_
      write(msg, '(a,1x,a)') '*', trim(message(ii))
      call flush_msg(msg, stderr)
    end do
 
    ! We only dump the stack in debug mode because subroutine invocations
    ! are only recorded in debug mode (via push_sub/pop_sub). Otherwise,
    ! it is a bit confusing that the stack seems to be empty.
    if (debug%trace) then
      call flush_msg(shyphens, stderr)
 
      write(msg, '(a)') '* Stack: '
      call flush_msg(msg, stderr, adv='no')
      do ii = 1, no_sub_stack
        write(msg, '(a,a)') ' > ', trim(sub_stack(ii))
        call flush_msg(msg, stderr, adv='no')
      end do
      call flush_msg(" ", stderr)
    end if
 
    if (should_write) then
      call messages_print_with_emphasis(iunit=stderr)
    end if
 
    ! switch file indicator to state aborted
    call messages_switch_status('aborted')
 
    call mpi_world%abort()
 
    call loct_exit_failure()
  end subroutine messages_fatal
 
  ! ---------------------------------------------------------
  subroutine messages_warning(no_lines, all_nodes, namespace)
    integer,           optional, intent(in) :: no_lines
    logical,           optional, intent(in) :: all_nodes
    type(namespace_t), optional, intent(in) :: namespace
 
    integer :: il, no_lines_
    integer :: iunit_namespace
    logical :: have_to_write, all_nodes_
    type(mpi_grp_t) :: msg_mpi_grp
 
    no_lines_ = current_line
    if (present(no_lines)) no_lines_ = no_lines
 
    warnings = warnings + 1
 
    iunit_namespace = messages_get_unit(namespace)
    msg_mpi_grp = messages_get_mpi_grp(namespace)
 
    have_to_write = mpi_grp_is_root(msg_mpi_grp)
 
    all_nodes_ = .false.
    if (present(all_nodes)) then
      have_to_write = have_to_write .or. all_nodes
      all_nodes_ = all_nodes
    end if
 
    if (have_to_write) then
 
      call flush_msg('', stderr)
      if (iunit_namespace /= stdout) then
        call flush_msg('', iunit_namespace)
      end if
      write(msg, '(a)') '** Warning:'
      call flush_msg(msg, stderr)
      if (iunit_namespace /= stdout) then
        call flush_msg(msg, iunit_namespace)
      end if
 
      if (present(namespace)) then
        if (len_trim(namespace%get()) > 0) then
          write(msg, '(3a)') '** In namespace ', trim(namespace%get()), ':'
          call flush_msg(msg, stderr)
        end if
      end if
 
#ifdef HAVE_MPI
      if (all_nodes_) then
        write(msg , '(a,i4)') '** From node = ', mpi_world%rank
        call flush_msg(msg, stderr)
        if (iunit_namespace /= stdout) then
          call flush_msg(msg, iunit_namespace)
        end if
      end if
#endif
 
      do il = 1, no_lines_
        write(msg , '(a,3x,a)') '**', trim(message(il))
        call flush_msg(msg, stderr)
        if (iunit_namespace /= stdout) then
          call flush_msg(msg, iunit_namespace)
        end if
      end do
      call flush_msg('', stderr)
      if (iunit_namespace /= stdout) then
        call flush_msg('', iunit_namespace)
      end if
 
#ifdef HAVE_FLUSH
      call flush(stderr)
      if (iunit_namespace /= stdout) then
        flush(iunit_namespace)
      end if
#endif
 
    end if
 
    call messages_reset_lines()
 
  end subroutine messages_warning
 
  ! ---------------------------------------------------------
  subroutine messages_info(no_lines, iunit, verbose_limit, stress, all_nodes, namespace)
    integer,           optional, intent(in) :: no_lines
    integer,           optional, intent(in) :: iunit
    logical,           optional, intent(in) :: verbose_limit
    logical,           optional, intent(in) :: stress
    logical,           optional, intent(in) :: all_nodes
    type(namespace_t), optional, intent(in) :: namespace
 
    integer :: il, no_lines_
    integer :: iunit_
    type(mpi_grp_t) :: msg_mpi_grp
 
    assert(.not. (present(iunit) .and. present(namespace)))
 
    if (present(iunit)) then
      iunit_ = iunit
    else
      iunit_ = messages_get_unit(namespace)
    end if
    msg_mpi_grp = messages_get_mpi_grp(namespace)
 
    if (.not. mpi_grp_is_root(msg_mpi_grp) .and. .not. optional_default(all_nodes, .false.)) then
      call messages_reset_lines()
      return
    end if
 
    no_lines_ = current_line
    if (present(no_lines)) no_lines_ = no_lines
 
    if (present(stress)) then
      call messages_print_with_emphasis(iunit=iunit_)
    end if
 
    do il = 1, no_lines_
      if (.not. present(verbose_limit) .or. debug%info) then
        write(msg, '(a)') trim(message(il))
        call flush_msg(msg, iunit_)
      end if
    end do
    if (present(stress)) then
      call messages_print_with_emphasis(iunit=iunit_)
    end if
 
#ifdef HAVE_FLUSH
    call flush(iunit_)
#endif
 
    call messages_reset_lines()
 
  end subroutine messages_info
 
  ! ---------------------------------------------------------
  subroutine messages_switch_status(status)
    character(len=*), intent(in) :: status
 
    ! only root node is taking care of file I/O
    if (.not. mpi_grp_is_root(mpi_world)) return
 
    ! remove old status files first, before we switch to a new state
    call loct_rm(trim(msg_dir) // '/oct-status-running')
    call loct_rm(trim(msg_dir) // '/oct-status-finished')
    call loct_rm(trim(msg_dir) // '/oct-status-aborted')
    if (oct_status /= 'walltimer-aborted') then
      call loct_rm(trim(msg_dir) // '/oct-status-walltimer-aborted')
    end if
 
    oct_status = status
 
    ! create empty status file to indicate new state
    open(unit=iunit_err, file=trim(msg_dir) // '/oct-status-'//trim(status), &
      action='write', status='unknown')
    close(iunit_err)
 
  end subroutine messages_switch_status
 
  ! ---------------------------------------------------------
  subroutine alloc_error(size, file, line)
    integer(int64),      intent(in) :: size
    character(len=*), intent(in) :: file
    integer,          intent(in) :: line
 
    write(message(1), '(a,i18,3a,i5)') "Failed to allocate ", size, " words in file '", trim(file), "' line ", line
    call messages_fatal(1)
 
  end subroutine alloc_error
 
  ! ---------------------------------------------------------
  subroutine dealloc_error(size, file, line)
    integer(int64),      intent(in) :: size
    character(len=*), intent(in) :: file
    integer,          intent(in) :: line
 
    write(message(1), '(a,i18,3a,i5)') "Failed to deallocate array of ", size, " words in file '", trim(file), "' line ", line
    call messages_fatal(1)
 
  end subroutine dealloc_error
 
  ! ---------------------------------------------------------
  subroutine messages_input_error(namespace, var, details, row, column)
    type(namespace_t),          intent(in) :: namespace
    character(len=*),           intent(in) :: var
    character(len=*), optional, intent(in) :: details
    integer,          optional, intent(in) :: row
    integer,          optional, intent(in) :: column
 
    character(len=10) :: row_str, column_str
 
    call messages_write('Input error in the input variable '// trim(var))
 
    if (present(row)) then
      ! Print row and, if available, the column. We add one to both values
      ! in order to translate from the C numbering used by the parser to a
      ! more human-friendly numbering.
      write(row_str, '(I10)') row + 1
      call messages_write(' at row '//adjustl(row_str))
      if (present(column)) then
        write(column_str, '(I10)') column + 1
        call messages_write(', column '//adjustl(column_str))
      end if
    end if
    if (present(details)) then
      call messages_write(':', new_line = .true.)
      call messages_new_line()
      call messages_write('  '//trim(details))
    end if
    call messages_write('.', new_line = .true.)
 
    call messages_new_line()
 
    call messages_write('You can get the documentation of the variable with the command:', new_line = .true.)
    call messages_write('  oct-help -p '//trim(var))
    call messages_fatal(namespace=namespace)
 
  end subroutine messages_input_error
 
  ! ---------------------------------------------------------
  subroutine messages_print_var_valuei(var, val, iunit, namespace)
    character(len=*),            intent(in) :: var
    integer,                     intent(in) :: val
    integer,           optional, intent(in) :: iunit
    type(namespace_t), optional, intent(in) :: namespace
 
    character(len=10) :: intstring
 
    assert(.not. (present(iunit) .and. present(namespace)))
 
    write(intstring,'(i10)') val
    message(1) = 'Input: ['//trim(var)//' = '//trim(adjustl(intstring))//']'
    call messages_info(1, iunit=iunit, namespace=namespace)
 
  end subroutine messages_print_var_valuei
 
  ! ---------------------------------------------------------
  subroutine messages_print_var_values(var, val, iunit, namespace)
    character(len=*),            intent(in) :: var
    character(len=*),            intent(in) :: val
    integer,           optional, intent(in) :: iunit
    type(namespace_t), optional, intent(in) :: namespace
 
    assert(.not. (present(iunit) .and. present(namespace)))
 
    message(1) = 'Input: ['//trim(var)//' = '//trim(val)//']'
    call messages_info(1, iunit=iunit, namespace=namespace)
 
  end subroutine messages_print_var_values
 
  ! ---------------------------------------------------------
  subroutine messages_print_var_valuer(var, val, unit, iunit, namespace)
    character(len=*),            intent(in) :: var
    real(real64),                intent(in) :: val
    type(unit_t),      optional, intent(in) :: unit
    integer,           optional, intent(in) :: iunit
    type(namespace_t), optional, intent(in) :: namespace
 
    character(len=11) :: floatstring
 
    assert(.not. (present(iunit) .and. present(namespace)))
 
    if (.not. present(unit)) then
      write(floatstring,'(g11.4)') val
      message(1) = 'Input: ['//trim(var)//' = '//trim(adjustl(floatstring))//']'
    else
      write(floatstring,'(g11.4)') units_from_atomic(unit, val)
      message(1) = 'Input: ['//trim(var)//' = '//trim(adjustl(floatstring))//' '//trim(units_abbrev(unit))//']'
    end if
    call messages_info(1, iunit=iunit, namespace=namespace)
 
  end subroutine messages_print_var_valuer
 
  ! ---------------------------------------------------------
  subroutine messages_print_var_valuel(var, val, iunit, namespace)
    character(len=*),            intent(in) :: var
    logical,                     intent(in) :: val
    integer,           optional, intent(in) :: iunit
    type(namespace_t), optional, intent(in) :: namespace
 
    character(len=3) :: lstring
 
    assert(.not. (present(iunit) .and. present(namespace)))
 
    if (val) then
      lstring = 'yes'
    else
      lstring = 'no'
    end if
    message(1) = 'Input: ['//trim(var)//' = '//trim(lstring)//']'
    call messages_info(1, iunit=iunit, namespace=namespace)
 
  end subroutine messages_print_var_valuel
 
  ! ---------------------------------------------------------
  subroutine messages_print_var_valuear(var, val, unit, iunit, namespace)
    character(len=*),            intent(in) :: var
    real(real64),                intent(in) :: val(:)
    type(unit_t),      optional, intent(in) :: unit
    integer,           optional, intent(in) :: iunit
    type(namespace_t), optional, intent(in) :: namespace
 
    integer :: ii
    character(len=11) :: floatstring
 
    assert(.not. (present(iunit) .and. present(namespace)))
 
    call messages_write('Input: ['//trim(var)//' = (')
    do ii = 1, size(val)
      write(floatstring,'(g11.4)') val(ii)
      call messages_write(trim(adjustl(floatstring)))
      if (ii < size(val)) call messages_write(', ')
    end do
    call messages_write(')')
    if (present(unit)) then
      call messages_write(' '//trim(units_abbrev(unit))//']')
    else
      call messages_write(']')
    end if
    call messages_info(iunit = iunit, namespace=namespace)
 
  end subroutine messages_print_var_valuear
 
  ! ---------------------------------------------------------
  subroutine messages_print_var_info(var, iunit, namespace)
    character(len=*),            intent(in) :: var
    integer,           optional, intent(in) :: iunit
    type(namespace_t), optional, intent(in) :: namespace
 
    integer :: iunit_
    type(mpi_grp_t) :: mpi_grp
 
    assert(.not. (present(iunit) .and. present(namespace)))
 
    mpi_grp = messages_get_mpi_grp(namespace)
 
    if (.not. mpi_grp_is_root(mpi_grp)) return
 
    if (present(iunit)) then
      iunit_ = iunit
    else
      iunit_ = messages_get_unit(namespace)
    end if
    call varinfo_print(iunit_, var)
 
  end subroutine messages_print_var_info
 
  ! ---------------------------------------------------------
  subroutine messages_print_var_option_8(var, option, pre, iunit, namespace)
    character(len=*),            intent(in) :: var
    integer(int64),                 intent(in) :: option
    character(len=*),  optional, intent(in) :: pre
    integer,           optional, intent(in) :: iunit
    type(namespace_t), optional, intent(in) :: namespace
 
    integer :: option4, iunit_
    type(mpi_grp_t) :: mpi_grp
 
    assert(.not. (present(iunit) .and. present(namespace)))
 
    mpi_grp = messages_get_mpi_grp(namespace)
    if (.not. mpi_grp_is_root(mpi_grp)) return
 
    option4 = int(option, int32)
 
    if (present(iunit)) then
      iunit_ = iunit
    else
      iunit_ = messages_get_unit(namespace)
    end if
    call varinfo_print_option(iunit_, var, option4, pre)
 
  end subroutine messages_print_var_option_8
 
  ! ---------------------------------------------------------
  subroutine messages_print_var_option_4(var, option, pre, iunit, namespace)
    character(len=*),            intent(in) :: var
    integer(int32),                 intent(in) :: option
    character(len=*),  optional, intent(in) :: pre
    integer,           optional, intent(in) :: iunit
    type(namespace_t), optional, intent(in) :: namespace
 
    assert(.not. (present(iunit) .and. present(namespace)))
 
    call messages_print_var_option_8(var, int(option, int64), pre, iunit, namespace)
 
  end subroutine messages_print_var_option_4
 
  ! ---------------------------------------------------------
  subroutine messages_print_with_emphasis(msg, iunit, namespace)
    character(len=*),  optional, intent(in) :: msg
    integer,           optional, intent(in) :: iunit
    type(namespace_t), optional, intent(in) :: namespace
 
    integer, parameter :: max_len = 70
 
    integer :: ii, jj, length
    integer :: iunit_
    character(len=70) :: str
    character(len=max_len) :: msg_combined
    type(mpi_grp_t) :: msg_mpi_grp
 
    if (present(iunit)) then
      iunit_ = iunit
    else
      iunit_ = messages_get_unit(namespace)
    end if
    msg_mpi_grp = messages_get_mpi_grp(namespace)
 
    if (.not. mpi_grp_is_root(msg_mpi_grp)) return
 
    if (present(msg)) then
      ! make sure we do not get a segfault for too long messages
      if (len_trim(msg) > max_len) then
        msg_combined = trim(msg(1:max_len))
      else
        msg_combined = trim(msg)
      end if
      length = len_trim(msg_combined)
 
      str = ''
      jj = 1
 
      do ii = 1, (max_len - (length + 2))/2
        str(jj:jj) = '*'
        jj = jj + 1
      end do
 
      str(jj:jj) = ' '
      jj = jj + 1
 
      do ii = 1, length
        str(jj:jj) = msg_combined(ii:ii)
        jj = jj + 1
      end do
 
      str(jj:jj) = ' '
      jj = jj + 1
 
      do ii = jj, max_len
        str(jj:jj) = '*'
        jj = jj + 1
      end do
 
      call flush_msg('', iunit_)   ! empty line
      call flush_msg(str, iunit_)  ! print out nice line with the header
    else
      do ii = 1, max_len
        str(ii:ii) = '*'
      end do
 
      call flush_msg(str, iunit_)  ! print out nice line with the header
      call flush_msg('', iunit_)   ! empty line
    end if
 
#ifdef HAVE_FLUSH
    call flush(iunit_)
#endif
  end subroutine messages_print_with_emphasis
 
  ! ---------------------------------------------------------
  subroutine flush_msg(str, iunit, adv)
    character(len = *),           intent(in) :: str
    integer,                      intent(in) :: iunit
    character(len = *), optional, intent(in) :: adv
 
    character(len = 20) :: adv_
 
    adv_ = 'yes'
    if (present(adv)) adv_ = trim(adv)
 
    write(iunit, '(a)', advance=adv_) trim(str)
 
  end subroutine flush_msg
 
  ! ---------------------------------------------------------
  subroutine print_date(str)
    character(len = *), intent(in) :: str
 
    integer :: val(8)
 
    call date_and_time(values=val)
    message(1) = ""
    write(message(3),'(a,i4,a1,i2.2,a1,i2.2,a,i2.2,a1,i2.2,a1,i2.2)') &
      str , val(1), "/", val(2), "/", val(3), &
      " at ", val(5), ":", val(6), ":", val(7)
    message(2) = str_center(trim(message(3)), 70)
    message(3) = ""
    call messages_info(3)
 
  end subroutine print_date
 
  ! ---------------------------------------------------------
  subroutine time_sum(sec1, usec1, sec2, usec2)
    integer, intent(in)    :: sec1
    integer, intent(in)    :: usec1
    integer, intent(inout) :: sec2
    integer, intent(inout) :: usec2
 
    push_sub(time_sum)
 
    sec2  = sec1 + sec2
    usec2 = usec1 + usec2
 
    ! Carry?
    if (usec2 >= 1000000) then
      sec2  = sec2 + 1
      usec2 = usec2 - 1000000
    end if
 
    pop_sub(time_sum)
  end subroutine time_sum
 
  ! ---------------------------------------------------------
  subroutine messages_obsolete_variable(namespace, name, rep)
    type(namespace_t),          intent(in) :: namespace
    character(len=*),           intent(in) :: name
    character(len=*), optional, intent(in) :: rep
 
    if (parse_is_defined(namespace, trim(name))) then
 
      write(message(1), '(a)') 'Input variable '//trim(name)//' is obsolete.'
 
      if (present(rep)) then
        write(message(2), '(a)') ' '
        write(message(3), '(a)') 'Equivalent functionality can be obtained with the '//trim(rep)
        write(message(4), '(a)') 'variable. Check the documentation for details.'
        write(message(5), '(a)') '(You can use the `oct-help -p '//trim(rep)//'` command).'
        call messages_fatal(5, only_root_writes = .true., namespace=namespace)
      else
        call messages_fatal(1, only_root_writes = .true., namespace=namespace)
      end if
 
    end if
 
  end subroutine messages_obsolete_variable
 
  ! ---------------------------------------------------------
  subroutine messages_variable_is_block(namespace, name)
    type(namespace_t),          intent(in) :: namespace
    character(len=*),           intent(in) :: name
 
    if (parse_is_defined(namespace, trim(name))) then
 
      write(message(1), '(a)') 'Input variable `'//trim(name)//'` must be defined as a block.'
      write(message(2), '(a)') 'Please check the documentation for details.'
      write(message(3), '(a)') '(You can use the `oct-help -p '//trim(name)//'` command).'
      call messages_fatal(3, only_root_writes = .true., namespace=namespace)
 
    end if
 
  end subroutine messages_variable_is_block
 
  ! ---------------------------------------------------------
  subroutine messages_experimental(name, namespace)
    character(len=*),  intent(in) :: name
    type(namespace_t), optional, intent(in) :: namespace
 
    experimentals = experimentals + 1
 
    if (.not. conf%devel_version) then
      call messages_write(trim(name)//' is an experimental feature.')
      call messages_new_line()
      call messages_new_line()
      call messages_write('If you still want to use this feature (at your own risk), check:')
      call messages_new_line()
      call messages_new_line()
      call messages_write('https://www.octopus-code.org/documentation/main/variables/execution/debug/experimentalfeatures')
      call messages_new_line()
      call messages_fatal(only_root_writes = .true., namespace=namespace)
    else
      write(message(1), '(a)') trim(name)//' is under development.'
      write(message(2), '(a)') 'It might not work or produce wrong results.'
      call messages_warning(2, namespace=namespace)
 
      ! remove this warning from the count
      warnings = warnings - 1
    end if
 
  end subroutine messages_experimental
 
  ! ------------------------------------------------------------
  subroutine messages_not_implemented(feature, namespace)
    character(len=*),            intent(in) :: feature
    type(namespace_t), optional, intent(in) :: namespace
 
    push_sub(messages_not_implemented)
 
    message(1) = trim(feature)//" not implemented."
    call messages_fatal(1, only_root_writes = .true., namespace=namespace)
 
    pop_sub(messages_not_implemented)
  end subroutine messages_not_implemented
 
  ! ------------------------------------------------------------
  subroutine messages_reset_lines()
 
    current_line = 1
    message(1) = ''
 
  end subroutine messages_reset_lines
 
  ! ------------------------------------------------------------
  subroutine messages_new_line()
 
    current_line = current_line + 1
    message(current_line) = ''
 
    if (current_line > max_lines) stop 'Too many message lines.'
 
  end subroutine messages_new_line
 
  ! ------------------------------------------------------------
  subroutine messages_write_float(val, fmt, new_line, units, align_left, print_units)
    real(real64),               intent(in) :: val
    character(len=*), optional, intent(in) :: fmt
    logical,          optional, intent(in) :: new_line
    type(unit_t),     optional, intent(in) :: units
    logical,          optional, intent(in) :: align_left
    logical,          optional, intent(in) :: print_units
 
    character(len=30) :: number
    real(real64)     :: tval
 
    tval = val
    if (present(units)) tval = units_from_atomic(units, val)
 
    if (present(fmt)) then
      write(number, '('//trim(fmt)//')') tval
    else
      write(number, '(f12.6)') tval
    end if
 
    if (optional_default(align_left, .false.)) then
      number = adjustl(number)
      number(1:len(number)) = ' '//number(1:len(number)-1)
    end if
 
    write(message(current_line), '(a, a)') trim(message(current_line)), trim(number)
 
    if (present(units) .and. optional_default(print_units, .true.)) then
      write(message(current_line), '(a, a, a)') trim(message(current_line)), ' ', trim(units_abbrev(units))
    end if
 
    if (optional_default(new_line, .false.)) call messages_new_line()
 
  end subroutine messages_write_float
 
  ! ------------------------------------------------------------
  subroutine messages_write_integer8(val, fmt, new_line, units, print_units)
    integer(int64),                intent(in) :: val
    character(len=*), optional, intent(in) :: fmt
    logical,          optional, intent(in) :: new_line
    type(unit_t),     optional, intent(in) :: units
    logical,          optional, intent(in) :: print_units
 
    character(len=20) :: number
    real(real64)      :: val_conv_float
 
    if (present(units)) then
      val_conv_float = units_from_atomic(units, dble(val))
 
      if (present(fmt)) then
        write(message(current_line), '(a, '//trim(fmt)//')') trim(message(current_line)), val_conv_float
      else
        write(number, '(f15.3)') val_conv_float
        write(message(current_line), '(3a)') trim(message(current_line)), ' ', trim(adjustl(number))
      end if
 
    else
 
      if (present(fmt)) then
        write(message(current_line), '(a, '//trim(fmt)//')') trim(message(current_line)), val
      else
        write(number, '(i12)') val
        write(message(current_line), '(3a)') trim(message(current_line)), ' ', trim(adjustl(number))
      end if
 
    end if
 
 
    if (present(units) .and. optional_default(print_units, .true.)) then
      write(message(current_line), '(a, a, a)') trim(message(current_line)), ' ', trim(adjustl(units_abbrev(units)))
    end if
 
    if (present(new_line)) then
      if (new_line) call messages_new_line()
    end if
 
  end subroutine messages_write_integer8
 
  ! ------------------------------------------------------------
  subroutine messages_write_integer(val, fmt, new_line, units, print_units)
    integer(int32),                intent(in) :: val
    character(len=*), optional, intent(in) :: fmt
    logical,          optional, intent(in) :: new_line
    type(unit_t),     optional, intent(in) :: units
    logical,          optional, intent(in) :: print_units
 
    call messages_write_integer8(int(val, int64), fmt, new_line, units, print_units)
 
  end subroutine messages_write_integer
 
  ! ------------------------------------------------------------
  subroutine messages_write_str(val, fmt, new_line)
    character(len=*),           intent(in) :: val
    character(len=*), optional, intent(in) :: fmt
    logical,          optional, intent(in) :: new_line
 
    character(len=100) :: fmt_
 
    if (len(trim(message(current_line))) + len(trim(val)) > len(message(current_line))) then
      ! cannot use normal message approach without interfering with message we are trying to write
      ! write directly in case trim(val) is itself too long
      write(0, *) "Exceeded message line length limit, to write string:", trim(val)
    else
      fmt_ = optional_default(fmt, '(a)')
      write(message(current_line), '(a, '//trim(fmt_)//')') trim(message(current_line)), trim(val)
    end if
 
    if (present(new_line)) then
      if (new_line) call messages_new_line()
    end if
 
  end subroutine messages_write_str
 
  ! ------------------------------------------------------------
  subroutine messages_write_logical(val, new_line)
    logical,           intent(in) :: val
    logical, optional, intent(in) :: new_line
 
    character(len=3) :: text
 
    if (val) then
      text = 'yes'
    else
      text = 'no'
    end if
 
    if (len(trim(message(current_line))) + len(trim(text)) > len(message(current_line))) then
      write(message(current_line + 1), '(3a)') "Exceeded message line length limit, to write logical value '", trim(text), "'"
      call messages_fatal(current_line + 1)
    end if
 
    write(message(current_line), '(a,1x,a)') trim(message(current_line)), trim(text)
 
    if (present(new_line)) then
      if (new_line) call messages_new_line()
    end if
 
  end subroutine messages_write_logical
 
  ! -----------------------------------------------------------
  subroutine messages_dump_stack(isignal)
    integer, intent(in) :: isignal
 
    integer :: ii
    character(len=300) :: description
 
    call get_signal_description(isignal, description)
 
    write(msg, '(a,i2)') ''
    call flush_msg(msg, stderr)
    write(msg, '(a,i2)') '%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
    call flush_msg(msg, stderr)
    write(msg, '(a,i2)') ''
    call flush_msg(msg, stderr)
    write(msg, '(a,i2,2a)') '  Octopus was killed by signal ', isignal, ': ', trim(description)
    call flush_msg(msg, stderr)
    write(msg, '(a,i2)') ''
    call flush_msg(msg, stderr)
    write(msg, '(a)')    '  Note: Octopus is currently trapping signals. This might prevent the'
    call flush_msg(msg, stderr)
    write(msg, '(a)')    '  use of debuggers or the generation of core dumps. To change this'
    call flush_msg(msg, stderr)
    write(msg, '(a)')    '  behavior, use the DebugTrapSignals input option.'
    call flush_msg(msg, stderr)
    write(msg, '(a,i2)') ''
    call flush_msg(msg, stderr)
    write(msg, '(a,i2)') '%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%'
    call flush_msg(msg, stderr)
 
    if (debug%trace) then
      call flush_msg(shyphens, iunit=stderr)
 
      write(msg, '(a)') 'Octopus debug trace: '
      call flush_msg(msg, stderr)
      do ii = 1, no_sub_stack
        write(msg, '(a,a)') ' > ', trim(sub_stack(ii))
        call flush_msg(msg, stderr, adv='no')
      end do
      call flush_msg(" ", stderr)
    else
      write(msg, '(a)') " Octopus debug trace not available. You can enable it with 'Debug = trace'."
      call flush_msg(msg, stderr)
    end if
 
  end subroutine messages_dump_stack
 
end module messages_oct_m
 
! ---------------------------------------------------------
subroutine assert_die(s, f, l)
  use debug_oct_m
  use messages_oct_m
  use mpi_oct_m
 
  implicit none
 
  character(len=*), intent(in) :: s, f
  integer, intent(in) :: l
 
  call messages_write('Node ')
  call messages_write(mpi_world%rank)
  call messages_write(':')
  call messages_new_line()
 
  call messages_write(' Assertion "'//trim(s)//'"')
  call messages_new_line()
 
  call messages_write(' failed in line ')
  call messages_write(l)
  call messages_write(' of file "'//trim(debug_clean_path(f))//'".')
  call messages_new_line()
 
  call messages_write('This should not happen and is likely a bug in the code.')
  call messages_new_line()
  call messages_write('Please contact the developers and report how this occurred.')
  call messages_new_line()
  call messages_write('You can open an issue on gitlab as described in Contributing.md.')
  call messages_new_line()
 
  call messages_fatal()
 
end subroutine assert_die
 
!-------------------------------------------------------
subroutine handle_segv(isignal) bind(c)
  use messages_oct_m
  use iso_c_binding
 
  implicit none
 
  integer(c_int), intent(in) :: isignal
 
  ! Switch status to aborted
  call messages_switch_status('aborted')
 
  ! Dump stack
  call messages_dump_stack(isignal)
 
end subroutine handle_segv
 
 
!! Local Variables:
!! mode: f90
!! coding: utf-8
!! End: