%%	options

copyright owner	=	Dirk Krause
copyright year	=	2015-xxxx
license		=	bsd



%%	header

/**	@file
	Process command line option in simple programs.
	You can specify a set of allowed options including the option
	arguments types. After processing command line arguments you
	can simply check which options were used and obtain option
	argument values.
*/


#ifndef DK4CONF_H_INCLUDED
#include "dk4conf.h"
#endif

#ifndef DK4TYPES_H_INCLUDED
#include "dk4types.h"
#endif

#ifndef DK4ERROR_H_INCLUDED
#include "dk4error.h"
#endif

/**	Option specification for application module.
*/
typedef struct {
  dkChar	 c;		/**< Short option character. */
  const dkChar	*longopt;	/**< Long option string. */
  int		 argtype;	/**< Argument type. */
} dk4_option_specification_t;

/**	Option values can be different types.
*/
typedef	union	{
  dkChar			*t;	/**< String value. */
  double			 d;	/**< Double value. */
  dk4_im_t			 i;	/**< Integer value. */
  dk4_um_t			 u;	/**< Unsigned integer value. */
  size_t			 s;	/**< Size value. */
  int				 b;	/**< Boolean value. */
} dk4_option_value_t;

/**	Option with value.
*/
typedef struct {
  dk4_option_specification_t	spec;	/**< Option specification. */
  dk4_option_value_t 		val;	/**< Option value. */
  int				found;	/**< Flag: Option found in cmd line. */
} dk4_option_t;


/**	Argument types.
*/
enum {
			/**	No argument expected.
			*/
DK4_OPT_ARG_NONE	=	1,

			/**	Boolean value expected.
			*/
DK4_OPT_ARG_BOOL ,

			/**	Size specification expected.
			*/
DK4_OPT_ARG_SIZE ,

			/**	Signed integer value expected.
			*/
DK4_OPT_ARG_INT ,

			/**	Unsigned integer value expected.
			*/
DK4_OPT_ARG_UNSIGNED ,

			/**	Double value expected.
			*/
DK4_OPT_ARG_DOUBLE ,

			/**	String value expected.
			*/
DK4_OPT_ARG_STRING
};



#ifdef __cplusplus
extern "C" {
#endif

/**	Create option object.
	CRT on Windows: Optional.
	@param	spec	Specifications for the option.
	@param	erp	Error report, may be NULL.
	@return	Pointer to new option object on success, NULL on error.
	
	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if spec is NULL,
	- DK4_E_SYNTAX<br>
	  if neither short nor long option is defined in spec,
	- DK4_E_MEMORY<br>
	  if the memory allocation failed.
*/
dk4_option_t *
dk4opt_open(const dk4_option_specification_t *spec, dk4_er_t *erp);

/**	Retrieve boolean value (as int) from option.
	CRT on Windows: Optional.
	@param	dptr	Pointer to destination variable.
	@param	optptr	Option to retrieve value from.
	@param	erp	Error report, may be NULL.
	@return	1 on success, 0 on error.
	
	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if dptr or optptr is NULL or optptr is configured for another data
	  type,
	- DK4_E_NOT_FOUND<br>
	  if the option was not specified on the command line,
	- DK4_E_SYNTAX<br>
	  if a string is stored not representing a boolean or the option was
	  configured with an incompatible type.
*/
int
dk4opt_get_bool(int *dptr, dk4_option_t *optptr, dk4_er_t *erp);

/**	Retrieve size_t value from option.
	CRT on Windows: Optional.
	@param	dptr	Pointer to destination variable.
	@param	optptr	Option to retrieve value from.
	@param	erp	Error report, may be NULL.
	@return	1 on success, 0 on error.
	
	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if dptr or optptr is NULL or optptr is configured for another data
	  type,
	- DK4_E_NOT_FOUND<br>
	  if the option was not specified on the command line,
	- DK4_E_SYNTAX<br>
	  if the option was configured for an incompatible type or the option
	  argument string can not be converted to a size_t,
	- DK4_E_MATH_OVERFLOW<br>
	  if the option was configured for another numeric type and conversion
	  results in an overflow.
*/
int
dk4opt_get_size(size_t *dptr, dk4_option_t *optptr, dk4_er_t *erp);

/**	Retrieve integer value (dk4_im_t) from option.
	CRT on Windows: Optional.
	@param	dptr	Pointer to destination variable.
	@param	optptr	Option to retrieve value from.
	@param	erp	Error report, may be NULL.
	@return	1 on success, 0 on error.
	
	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if dptr or optptr is NULL or optptr is configured for another data
	  type,
	- DK4_E_NOT_FOUND<br>
	  if the option was not specified on the command line,
	- DK4_E_SYNTAX<br>
	  if the option was configured for an incompatible type or the option
	  argument string does not represent an integer number,
	- DK4_E_MATH_OVERFLOW<br>
	  if the option was configured for another numeric type and conversion
	  results in an overflow.
*/
int
dk4opt_get_int(dk4_im_t *dptr, dk4_option_t *optptr, dk4_er_t *erp);

/**	Retrieve unsigned integer value (dk4_um_t) from option.
	CRT on Windows: Optional.
	@param	dptr	Pointer to destination variable.
	@param	optptr	Option to retrieve value from.
	@param	erp	Error report, may be NULL.
	@return	1 on success, 0 on error.
	
	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if dptr or optptr is NULL or optptr is configured for another data
	  type,
	- DK4_E_NOT_FOUND<br>
	  if the option was not specified on the command line,
	- DK4_E_SYNTAX<br>
	  if the option was configured for an incompatible data type or the
	  option string does not represent an integer number,
	- DK4_E_MATH_OVERFLOW<br>
	  if the option was configured for an incompatible numeric type and a
	  negative value is stored.
*/
int
dk4opt_get_unsigned(dk4_um_t *dptr, dk4_option_t *optptr, dk4_er_t *erp);

/**	Retrieve double value from option.
	CRT on Windows: Optional.
	@param	dptr	Pointer to destination variable.
	@param	optptr	Option to retrieve value from.
	@param	erp	Error report, may be NULL.
	@return	1 on success, 0 on error.
	
	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if dptr or optptr is NULL or optptr is configured for another data
	  type,
	- DK4_E_NOT_FOUND<br>
	  if the option was not specified on the command line,
	- DK4_E_SYNTAX<br>
	  if the option was configured for an incompatible data type or the
	  string stored as option argument does not represent a double number.
*/
int
dk4opt_get_double(double *dptr, dk4_option_t *optptr, dk4_er_t *erp);

/**	Retrieve string value from option.
	CRT on Windows: Optional, disabling CRT reduces functionality
	as we can not convert double values to strings.
	@param	dptr	Pointer to destination buffer.
	@param	szdptr	Size of destination buffer (number of dkChar).
	@param	optptr	Option to retrieve value from.
	@param	erp	Error report, may be NULL.
	@return	1 on success, 0 on error.
	
	Error codes:
	- DK4_E_INVALID_ARGUMENTS<br>
	  if dptr or optptr is NULL or optptr is configured for another data
	  type,
	- DK4_E_NOT_FOUND<br>
	  if the option was not specified on the command line.
	- DK4_E_SYNTAX<br>
	  if the option was configured for an incompatible data type,
	- DK4_E_BUFFER_TOO_SMALL<br>
	  if the destination buffer is too small to hold a conversion result,
	- DK4_E_NOT_SUPPORTED<br>
	  if the option was configured for the double data type and the use of
	  sprintf() was denied during setup.
*/
int
dk4opt_get_string(
  dkChar *dptr, size_t szdptr, dk4_option_t *optptr, dk4_er_t *erp
);

/**	Destroy option object, release memory.
	CRT on Windows: Optional.
	@param	optptr	Option object to destroy.
*/
void
dk4opt_close(dk4_option_t *optptr);

/**	Compare option against other option or char or string.
	CRT on Windows: Optional.
	@param	l	Left pointer, always an option.
	@param	r	Right pointer, type depends on cr.
	@param	cr	Comparison criteria:
			0=option/option by short character,
			1=option/character,
			2=option/option by long option text,
			3=option/text.
	@return	Comparison result.
*/
int
dk4option_compare(const void *l, const void *r, int cr);

/**	Process command line options provided to the main function.
	@param	optptr		Options array.
	@param	szoptptr	Number of elements in array.
	@param	argc		Number of command line arguments.
	@param	argv		Command line arguments array.
	@param	filenames	Pointer array to store file names.
	@param	nfilenames	Elements in array (in: size, out: used).
	@param	progname	Flag: Argument 0 is program name.
	@param	logstderr	Flag: Logging to stderr allowed.
	@param	erp		Error report, may be NULL.
	@return	1 on success, 0 on error.
*/
int
dk4opt_process_argv(
  dk4_option_t		 *optptr,
  size_t		  szoptptr,
  int			  argc,
  dkChar		 *argv[],
  dkChar		**filenames,
  size_t		 *nfilenames,
  int			  progname,
  int			  logstderr,
  dk4_er_t		 *erp
);

#ifdef __cplusplus
}
#endif

%%	module



#include "dk4opt.h"
#include "dk4strd.h"
#include "dk4mem.h"



$!trace-include



/**	Compare two options by short option.
	@param	olp	Left option structure.
	@param	orp	Right option structure.
	@return	Comparison result.
*/
static
int
dk4option_short_compare(const dk4_option_t *olp, const dk4_option_t *orp)
{
  int		back	= 0;
  if ((olp->spec).c > (orp->spec).c) {
    back = 1;
  } else {
    if ((olp->spec).c < (orp->spec).c) {
      back = -1;
    }
  }
  return back;
}



/**	Compare two options by long option.
	@param	olp	Left option structure.
	@param	orp	Right option structure.
	@return	Comparison result.
*/
static
int
dk4option_long_compare(const dk4_option_t *olp, const dk4_option_t *orp)
{
  int		 back = 0;
  if (NULL != (olp->spec).longopt) {
    if (NULL != (orp->spec).longopt) {
      back = dk4str_cmp((olp->spec).longopt, (orp->spec).longopt);
      if (-1 > back) back = -1;
      if ( 1 < back) back =  1;
    } else {
      back = 1;
    }
  } else {
    if (NULL != (orp->spec).longopt) {
      back = -1;
    }
  }
  return back;
}



int
dk4option_compare(const void *l, const void *r, int cr)
{
  const dk4_option_t	*olp;
  const dk4_option_t	*orp;
  const dkChar		*cp;

  int		back = 0;
  if (NULL != l) {
    olp = (const dk4_option_t *)l;
    if (NULL != r) {
      switch (cr) {
        case 3: {
	  cp  = (const dkChar *)r;
	  if (NULL != (olp->spec).longopt) {
	    back = dk4str_cmp((olp->spec).longopt, cp);
	    if (-1 > back) back = -1;
	    if ( 1 < back) back =  1;
	  } else {
	    back = -1;
	  }
	} break;
	case 2: {
	  orp = (const dk4_option_t *)r;
	  back = dk4option_long_compare(olp, orp);
	  if (0 == back) {
	    back = dk4option_short_compare(olp, orp);
	  }
	} break;
	case 1: {
	  cp  = (const dkChar *)r;
	  if ((olp->spec).c > *cp) {
	    back = 1;
	  } else {
	    if ((olp->spec).c < *cp) {
	      back = -1;
	    }
	  }
	} break;
	default: {
	  orp = (const dk4_option_t *)r;
	  back = dk4option_short_compare(olp, orp);
	  if (0 == back) {
	    back = dk4option_long_compare(olp, orp);
	  }
	} break;
      }
    } else {
      back = 1;
    }
  } else {
    if (NULL != r) {
      back = -1;
    }
  }
  return back;
}



void
dk4opt_close(dk4_option_t *optptr)
{
  $? "+ dk4opt_close"
  if (NULL != optptr) {		$? ". valid option ptr"
    /*
	We can not sanitize the memory for option name and option value
	as the option name is constant and the option value was provided
	by the shell and is owned by the shell.
    */
    (optptr->spec).longopt = NULL;
    (optptr->val).t = NULL;
    dk4mem_free(optptr);
  }
  $? "- dk4opt_close"
}



dk4_option_t *
dk4opt_open(const dk4_option_specification_t *spec, dk4_er_t *erp)
{
  dk4_option_t	*back	=	NULL;
  if (NULL != spec) {
    if ((NULL != spec->longopt) || (dkT('\0') != spec->c)) {
      back = dk4mem_new(dk4_option_t,1,NULL);
      if (NULL != back) {
	DK4_MEMCPY(&(back->spec),spec,sizeof(dk4_option_specification_t));
	back->found = 0;
	switch ((back->spec).argtype) {
	  case DK4_OPT_ARG_BOOL: {
	    (back->val).b = 0;
	  } break;
	  case DK4_OPT_ARG_SIZE: {
	    (back->val).s = 0;
	  } break;
	  case DK4_OPT_ARG_INT: {
	    (back->val).i = (dk4_im_t)0L;
	  } break;
	  case DK4_OPT_ARG_UNSIGNED: {
	    (back->val).u = (dk4_um_t)0UL;
	  } break;
	  case DK4_OPT_ARG_DOUBLE: {
	    (back->val).d = 0.0;
	  } break;
	  case DK4_OPT_ARG_STRING: {
	    (back->val).t = NULL;
	  } break;
	}
      } else {
        dk4error_set_elsize_nelem(
	  erp, DK4_E_MEMORY_ALLOCATION_FAILED, sizeof(dk4_option_t), 1
	);
      }
    } else {
      dk4error_set_simple_error_code(erp, DK4_E_SYNTAX);
    }
  } else {
    dk4error_set_simple_error_code(erp, DK4_E_INVALID_ARGUMENTS);
  }
  return back;
}