/*
 *  lexgen.c - Portable program to GENerate LEXical tables.
 */

#include <stdio.h>
#include <stdlib.h>

#if __STDC__            /* if ANSI C compiler   */
#include <limits.h>
#endif

#ifndef UCHAR_MAX       /* define it ourselves as last resort. */
#define UCHAR_MAX   ((unsigned)255)
#endif

#include "chclass.h"

#define OUTFILE "cctable.c"
#define UALPHA  "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
#define LALPHA  "abcdefghijklmnopqrstuvwxyz"
#define DIGIT   "0123456789"

char    _cctable[1];        /* dummy to satisfy extern in chclass.h */


main(int argc, char **argv){
    unsigned char *gentab = (unsigned char *)calloc(UCHAR_MAX+1, sizeof(char));
    void    settab(unsigned char *table, int bit, char *chars);
    void    prntab(unsigned char *table, FILE *fout);
    FILE    *fout;

    if( (fout = fopen(OUTFILE, "w")) == NULL){
        fprintf(stderr, "%s: Can't open '%s' for output\n", argv[0], OUTFILE);
        exit(EXIT_FAILURE);
        }
    
    settab(gentab, _CCID1_,     UALPHA LALPHA "_");
    settab(gentab, _CCID_,      UALPHA LALPHA "_" DIGIT);
    settab(gentab, _CCEXP_,     "eE");
    settab(gentab, _CCSIGN_,    "-+");
    prntab(gentab, fout);
    fclose(fout);
}

void    settab(unsigned char *table, int  bit, char *chars) {
    while(*chars)
        table[*chars++]   |= bit;       /* turn on correct bit  */
}

void    prntab(unsigned char *table, FILE *fout) {
    unsigned    i;

    fprintf(fout, "\
/*\n\
 *  %s - character classification table.\n\
 */\n\
\n\
char    _cctable[]  =   {\n\
",                                          OUTFILE);

    for(i = 0; i <= UCHAR_MAX; ++i) {
        if(i)
            fputs(",", fout);
        fprintf(fout, (i%8) ? " " : "\n    ");
        fprintf(fout, "0x%0X", table[i]);
        }
    fprintf(fout, "\n    };\n");
    }