/*!@file
  \brief   lexical analyzer implementation for APC
  \details The lexer manages two FIFO stacks.  One for maintaining tokens, the
           other for maintaining a list of files to be scanned.  During
           execution, the lexer will return a token from its token queue if any
           are present.  If not, the lexer will will pop an element from its
           file queue to 'scanner' to be tokenized.  If the file queue is empty,
           the lexer will instead call 'parsedir' to traverse the directory tree
           and tokenize the results.  If 'parsedir' does not generate any new
           tokens, we are done.
  \author  Jordan Lavatai
  \date    Aug 2016
  ----------------------------------------------------------------------------*/
/* Standard */
#include <stdio.h>
#include <string.h>
#include <stdint.h>
#include <errno.h>
/* Posix */
#include <unistd.h>
#include <unitypes.h>
#include <unistr.h>
#include <uniconv.h>
#include <uniname.h>
#include <unistdio.h>
#include <stdlib.h>
#include <dirent.h>
/* Local */
#include "apc.h"
#include "parser.tab.h"
/* Public */
int lexer_lexfile(uint8_t const*);
/* Private */
extern //lexer.rl
int lexer_lexstring(uint8_t const*, int);
extern //scanner.c
yypstate* apc_pstate;
extern //scanner.c
yycstate* apc_cstate;
#define PUSHTOK(T,L) yypush_parse(apc_pstate, T, L, apc_cstate)

/* Lexical analysis of a file
   Strips a filename to its base name, then sends it to lexer_lexstring before
   pushing a PATH token with the filename
   Returns the number of tokens pushed to the parser.
*/
int lexer_lexfile
( uint8_t const* filename )
{ uint8_t const* last_period,* iter;
  int            ntok;
  last_period = NULL;
  for (iter = filename; *iter; iter++)
    if (*iter ==  '.')
      last_period = iter;
  if (last_period)
    { ntok = lexer_lexstring(filename, (int)(last_period - filename));
      PUSHTOK(PATH,filename);
      return ntok + 1;
    }
  return lexer_lexstring(filename, (int)(iter - filename));
}