/* Implementation of the GETARG and IARGC g77, and
   corresponding F2003, intrinsics. 
   Copyright (C) 2004-2024 Free Software Foundation, Inc.
   Contributed by Bud Davis and Janne Blomqvist.

This file is part of the GNU Fortran 95 runtime library (libgfortran).

Libgfortran 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 3 of the License, or (at your option) any later version.

Libgfortran 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.

Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
<http://www.gnu.org/licenses/>.  */

#include "libgfortran.h"
#include <string.h>


/* Get a commandline argument.  */

extern void getarg_i4 (GFC_INTEGER_4 *, char *, gfc_charlen_type);
iexport_proto(getarg_i4);

void 
getarg_i4 (GFC_INTEGER_4 *pos, char  *val, gfc_charlen_type val_len)
{
  int argc;
  char **argv;

  get_args (&argc, &argv);

  if (val_len < 1 || !val )
    return;   /* something is wrong , leave immediately */
  
  memset (val, ' ', val_len);

  if ((*pos) + 1 <= argc  && *pos >=0 )
    {
      gfc_charlen_type arglen = strlen (argv[*pos]);
      if (arglen > val_len)
	arglen = val_len;
      memcpy (val, argv[*pos], arglen);
    }
}
iexport(getarg_i4);


/* INTEGER*8 wrapper of getarg.  */

extern void getarg_i8 (GFC_INTEGER_8 *, char *, gfc_charlen_type);
export_proto (getarg_i8);

void 
getarg_i8 (GFC_INTEGER_8 *pos, char  *val, gfc_charlen_type val_len)
{
  GFC_INTEGER_4 pos4 = (GFC_INTEGER_4) *pos;
  getarg_i4 (&pos4, val, val_len);
}


/* Return the number of commandline arguments.  The g77 info page 
   states that iargc does not include the specification of the
   program name itself.  */

extern GFC_INTEGER_4 iargc (void);
export_proto(iargc);

GFC_INTEGER_4
iargc (void)
{
  int argc;
  char **argv;

  get_args (&argc, &argv);

  return (argc - 1);
} 


/* F2003 intrinsic functions and subroutines related to command line
   arguments.

   - function command_argument_count() is converted to iargc by the compiler.

   - subroutine get_command([command, length, status]).

   - subroutine get_command_argument(number, [value, length, status]).
*/

/* These two status codes are specified in the standard. */
#define GFC_GC_SUCCESS 0
#define GFC_GC_VALUE_TOO_SHORT -1

/* Processor-specific status failure code. */
#define GFC_GC_FAILURE 42


extern void get_command_argument_i4 (GFC_INTEGER_4 *, char *, GFC_INTEGER_4 *,
				     GFC_INTEGER_4 *, gfc_charlen_type);
iexport_proto(get_command_argument_i4);

/* Get a single commandline argument.  */

void
get_command_argument_i4 (GFC_INTEGER_4 *number, char *value, 
			 GFC_INTEGER_4 *length, GFC_INTEGER_4 *status, 
			 gfc_charlen_type value_len)
{
  int argc, stat_flag = GFC_GC_SUCCESS;
  gfc_charlen_type arglen = 0;
  char **argv;

  if (number == NULL )
    /* Should never happen.  */
    runtime_error ("Missing argument to get_command_argument");

  if (value == NULL && length == NULL && status == NULL)
    return; /* No need to do anything.  */

  get_args (&argc, &argv);

  if (*number < 0 || *number >= argc)
    stat_flag = GFC_GC_FAILURE;
  else
    arglen = strlen(argv[*number]);    

  if (value != NULL)
    {
      if (value_len < 1)
	stat_flag = GFC_GC_FAILURE;
      else
	memset (value, ' ', value_len);
    }

  if (value != NULL && stat_flag != GFC_GC_FAILURE)
    {
      if (arglen > value_len)
	 stat_flag = GFC_GC_VALUE_TOO_SHORT;

      memcpy (value, argv[*number], arglen <= value_len ? arglen : value_len);
    }

  if (length != NULL)
    *length = arglen;

  if (status != NULL)
    *status = stat_flag;
}
iexport(get_command_argument_i4);


/* INTEGER*8 wrapper for get_command_argument.  */

extern void get_command_argument_i8 (GFC_INTEGER_8 *, char *, GFC_INTEGER_8 *, 
				     GFC_INTEGER_8 *, gfc_charlen_type);
export_proto(get_command_argument_i8);

void
get_command_argument_i8 (GFC_INTEGER_8 *number, char *value, 
			 GFC_INTEGER_8 *length, GFC_INTEGER_8 *status, 
			 gfc_charlen_type value_len)
{
  GFC_INTEGER_4 number4;
  GFC_INTEGER_4 length4;
  GFC_INTEGER_4 status4;

  number4 = (GFC_INTEGER_4) *number;
  get_command_argument_i4 (&number4, value, &length4, &status4, value_len);
  if (length)
    *length = length4;
  if (status)
    *status = status4;
}


/* Return the whole commandline.  */

extern void get_command_i4 (char *, GFC_INTEGER_4 *, GFC_INTEGER_4 *,
			    gfc_charlen_type);
iexport_proto(get_command_i4);

void
get_command_i4 (char *command, GFC_INTEGER_4 *length, GFC_INTEGER_4 *status,
		gfc_charlen_type command_len)
{
  int i, argc, thisarg;
  int stat_flag = GFC_GC_SUCCESS;
  char **argv;
  gfc_charlen_type arglen, tot_len = 0;

  if (command == NULL && length == NULL && status == NULL)
    return; /* No need to do anything.  */

  get_args (&argc, &argv);

  if (command != NULL)
    {
      /* Initialize the string to blanks.  */
      if (command_len < 1)
	stat_flag = GFC_GC_FAILURE;
      else
	memset (command, ' ', command_len);
    }

  for (i = 0; i < argc ; i++)
    {
      arglen = strlen(argv[i]);

      if (command != NULL && stat_flag == GFC_GC_SUCCESS)
	{
	  thisarg = arglen;
	  if (tot_len + thisarg > command_len)
	    {
	      thisarg = command_len - tot_len; /* Truncate.  */
	      stat_flag = GFC_GC_VALUE_TOO_SHORT;
	    }
	  /* Also a space before the next arg.  */
	  else if (i != argc - 1 && tot_len + arglen == command_len)
	    stat_flag = GFC_GC_VALUE_TOO_SHORT;

	  memcpy (&command[tot_len], argv[i], thisarg);
	}

      /* Add the legth of the argument.  */
      tot_len += arglen;
      if (i != argc - 1)
	tot_len++;
    }

  if (length != NULL)
    *length = tot_len;

  if (status != NULL)
    *status = stat_flag;
}
iexport(get_command_i4);


/* INTEGER*8 wrapper for get_command.  */

extern void get_command_i8 (char *, GFC_INTEGER_8 *, GFC_INTEGER_8 *,
			    gfc_charlen_type);
export_proto(get_command_i8);

void
get_command_i8 (char *command, GFC_INTEGER_8 *length, GFC_INTEGER_8 *status,
		gfc_charlen_type command_len)
{
  GFC_INTEGER_4 length4;
  GFC_INTEGER_4 status4;

  get_command_i4 (command, &length4, &status4, command_len);
  if (length)
    *length = length4;
  if (status)
    *status = status4;
}