/* global.c: global command routines for the ed line editor */

/*  GNU ed - The GNU line editor.

    Copyright (C) 1993, 1994 Andrew Moore, Talke Studio

    Copyright (C) 2006-2017 Antonio Diaz Diaz.

    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 of the License, 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, see <http://www.gnu.org/licenses/>.

*/

#include <errno.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "ed.h"

static const line_t **active_list = 0;	/* list of lines active in a global command */

static int active_size = 0;	/* size (in bytes) of active_list */

static int active_len = 0;	/* number of lines in active_list */

static int active_ptr = 0;	/* active_list index ( non-decreasing ) */

static int active_ndx = 0;	/* active_list index ( modulo active_last ) */

/* clear the global-active list */

void clear_active_list( void )

  {

  disable_interrupts();

  if( active_list ) free( active_list );

  active_list = 0;

  active_size = active_len = active_ptr = active_ndx = 0;

  enable_interrupts();

  }

/* return the next global-active line node */

const line_t * next_active_node( void )

  {

  while( active_ptr < active_len && !active_list[active_ptr] )

    ++active_ptr;

  return ( active_ptr < active_len ) ? active_list[active_ptr++] : 0;

  }

/* add a line node to the global-active list */

bool set_active_node( const line_t * const lp )

  {

  disable_interrupts();

  if( !resize_line_buffer( &active_list, &active_size,

                           ( active_len + 1 ) * sizeof (line_t **) ) )

    {

    show_strerror( 0, errno );

    set_error_msg( "Memory exhausted" );

    enable_interrupts();

    return false;

    }

  enable_interrupts();

  active_list[active_len++] = lp;

  return true;

  }

/* remove a range of lines from the global-active list */

void unset_active_nodes( const line_t * bp, const line_t * const ep )

  {

  while( bp != ep )

    {

    int i;

    for( i = 0; i < active_len; ++i )

      {

      if( ++active_ndx >= active_len ) active_ndx = 0;

      if( active_list[active_ndx] == bp )

        { active_list[active_ndx] = 0; break; }

      }

    bp = bp->q_forw;

    }

  }