/*!@file
  \brief   APC main driver
  \details The driver assumes the existence of a bison-generated parser,
           referenced by the external function 'yyparse'.
           It also assumes the existence of a lexer which must be initialized
           before parsing, referenced by the external function 'lexer_init'
           which assumes standard error handling.
           All input arguments are made available through the exposed (that is,
           non-static) array of character pointers 'cargs', which point
           to the non-duplicated strings in 'argv' directly from the system.
  \author  Jordan Lavatai
  \date    Aug 2016
  ----------------------------------------------------------------------------*/
/* Standard */
#include <stdio.h>  //print
#include <errno.h>  //errors
#include <string.h> //strnlen
/* Posix */
#include <stdlib.h> //exit
#include <unistd.h> //getopt
/* Internal */
#include <apc/parser.tab.h> //bison

const char* cargs['Z'] = {0};

int main(int, char*[]);

extern //bison
int yyparse(void);
extern //lexer.c
int  lexer_init(void);

extern //apc/parser.tab.c
YYSTYPE yylval;
extern //lexer.c
int  lexer(void);

/* Main entry from terminal
   parses the command line and kicks off recursive scanning
*/
int main
( int   argc,
  char* argv[]
)
#define $($)#$ //stringifier
#define MAXSTR 255
#define MAXERR "-%c allows at most " $(MAXSTR) " input characters\n", opt
#define USAGE  "Usage: %s [-r root]\n", argv[0]
#define DONE   -1
{ int   opt;

 getopt:
  switch (opt = getopt(argc, argv, "r:o:"))
  { case DONE:
      break;
    case 'r' :
    case 'o' :
      if (strnlen(optarg, MAXSTR) != MAXSTR)
        { cargs[opt] = optarg;
          goto getopt;
        }
      fprintf(stderr, MAXERR);
    default :
      fprintf(stderr, USAGE);
      exit(EXIT_FAILURE);
  }
  if (lexer_init())
    { perror("lexer");
      exit(EXIT_FAILURE);
    }
  yyparse();
  exit(EXIT_SUCCESS);
}