flex.c

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/*************************************************************************\
* Copyright (c) 2002 The University of Chicago, as Operator of Argonne
*     National Laboratory.
* Copyright (c) 2002 The Regents of the University of California, as
*     Operator of Los Alamos National Laboratory.
* EPICS BASE is distributed subject to a Software License Agreement found
* in file LICENSE that is included with this distribution.
\*************************************************************************/
/* flex - tool to generate fast lexical analyzers */

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Vern Paxson.
 *
 * The United States Government has rights in this work pursuant
 * to contract no. DE-AC03-76SF00098 between the United States
 * Department of Energy and the University of California.
 *
 * Redistribution and use in source and binary forms are permitted provided
 * that: (1) source distributions retain this entire copyright notice and
 * comment, and (2) distributions including binaries display the following
 * acknowledgement:  ``This product includes software developed by the
 * University of California, Berkeley and its contributors'' in the
 * documentation or other materials provided with the distribution and in
 * all advertising materials mentioning features or use of this software.
 * Neither the name of the University nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#define ENQUOTE(path) #path

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1990 The Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */


#ifdef EPICS_BUILD_DLL
#  undef EPICS_BUILD_DLL
#endif
#ifdef EPICS_CALL_DLL
#  undef EPICS_CALL_DLL
#endif

#include "epicsTempFile.c"

static char flex_version[] = "2.3";


/* declare functions that have forward references */

void flexinit (int, char**);
void readin (void);
void set_up_initial_allocations (void);


/* these globals are all defined and commented in flexdef.h */
int printstats, syntaxerror, eofseen, ddebug, trace, spprdflt;
int interactive, caseins, useecs, fulltbl, usemecs;
int fullspd, gen_line_dirs, performance_report, backtrack_report, csize;
int yymore_used, reject, real_reject, continued_action;
int yymore_really_used, reject_really_used;
int datapos, dataline, linenum;
FILE *skelfile = NULL;
char *infilename = NULL;
int onestate[ONE_STACK_SIZE], onesym[ONE_STACK_SIZE];
int onenext[ONE_STACK_SIZE], onedef[ONE_STACK_SIZE], onesp;
int current_mns, num_rules, current_max_rules, lastnfa;
int *firstst, *lastst, *finalst, *transchar, *trans1, *trans2;
int *accptnum, *assoc_rule, *state_type, *rule_type, *rule_linenum;
int current_state_type;
int variable_trailing_context_rules;
int numtemps, numprots, protprev[MSP], protnext[MSP], prottbl[MSP];
int protcomst[MSP], firstprot, lastprot, protsave[PROT_SAVE_SIZE];
int numecs, nextecm[CSIZE + 1], ecgroup[CSIZE + 1], nummecs, tecfwd[CSIZE + 1];
int tecbck[CSIZE + 1];
int *xlation = (int *) 0;
int num_xlations;
int lastsc, current_max_scs, *scset, *scbol, *scxclu, *sceof, *actvsc;
char **scname;
int current_max_dfa_size, current_max_xpairs;
int current_max_template_xpairs, current_max_dfas;
int lastdfa, *nxt, *chk, *tnxt;
int *base, *def, *nultrans, NUL_ec, tblend, firstfree, **dss, *dfasiz;
union dfaacc_union *dfaacc;
int *accsiz, *dhash, numas;
int numsnpairs, jambase, jamstate;
int lastccl, current_maxccls, *cclmap, *ccllen, *cclng, cclreuse;
int current_max_ccl_tbl_size;
Char *ccltbl;
char *starttime, *endtime, nmstr[MAXLINE];
int sectnum, nummt, hshcol, dfaeql, numeps, eps2, num_reallocs;
int tmpuses, totnst, peakpairs, numuniq, numdup, hshsave;
int num_backtracking, bol_needed;
FILE *temp_action_file;
FILE *backtrack_file;
int end_of_buffer_state;
char **input_files;
int num_input_files;
char *program_name;

#ifndef SHORT_FILE_NAMES
static char *outfile = "lex.yy.c";
#else
static char *outfile = "lexyy.c";
#endif
static int outfile_created = 0;
static int use_stdout;
static char *skelname = NULL;


int main(int argc, char *argv[])
{
    flexinit( argc, argv );

    readin();

    if ( syntaxerror )
        flexend( 1 );

    if ( yymore_really_used == REALLY_USED )
        yymore_used = true;
    else if ( yymore_really_used == REALLY_NOT_USED )
        yymore_used = false;

    if ( reject_really_used == REALLY_USED )
        reject = true;
    else if ( reject_really_used == REALLY_NOT_USED )
        reject = false;

    if ( performance_report )
        {
        if ( interactive )
            fprintf( stderr,
                     "-I (interactive) entails a minor performance penalty\n" );

        if ( yymore_used )
            fprintf( stderr, "yymore() entails a minor performance penalty\n" );

        if ( reject )
            fprintf( stderr, "REJECT entails a large performance penalty\n" );

        if ( variable_trailing_context_rules )
            fprintf( stderr,
"Variable trailing context rules entail a large performance penalty\n" );
        }

    if ( reject )
        real_reject = true;

    if ( variable_trailing_context_rules )
        reject = true;

    if ( (fulltbl || fullspd) && reject )
        {
        if ( real_reject )
            flexerror( "REJECT cannot be used with -f or -F" );
        else
            flexerror(
        "variable trailing context rules cannot be used with -f or -F" );
        }

    ntod();

    /* generate the C state transition tables from the DFA */
    make_tables();

    /* note, flexend does not return.  It exits with its argument as status. */

    flexend( 0 );

    /*NOTREACHED*/
}


/* flexend - terminate flex
 *
 * synopsis
 *    int status;
 *    flexend( status );
 *
 *    status is exit status.
 *
 * note
 *    This routine does not return.
 */

void flexend(int status)
{
    int tblsiz;
    char *flex_gettime();

    if ( skelfile != NULL )
        {
        if ( ferror( skelfile ) )
            flexfatal( "error occurred when writing skeleton file" );

        else if ( fclose( skelfile ) )
            flexfatal( "error occurred when closing skeleton file" );
        }

    if ( temp_action_file )
        {
        if ( ferror( temp_action_file ) )
            flexfatal( "error occurred when writing temporary action file" );

        else if ( fclose( temp_action_file ) )
            flexfatal( "error occurred when closing temporary action file" );
    }

    if ( status != 0 && outfile_created )
        {
        if ( ferror( stdout ) )
            flexfatal( "error occurred when writing output file" );

        else if ( fclose( stdout ) )
            flexfatal( "error occurred when closing output file" );

        else if ( unlink( outfile ) )
            flexfatal( "error occurred when deleting output file" );
        }

    if ( backtrack_report && backtrack_file )
        {
        if ( num_backtracking == 0 )
            fprintf( backtrack_file, "No backtracking.\n" );
        else if ( fullspd || fulltbl )
            fprintf( backtrack_file,
                     "%d backtracking (non-accepting) states.\n",
                     num_backtracking );
        else
            fprintf( backtrack_file, "Compressed tables always backtrack.\n" );

        if ( ferror( backtrack_file ) )
            flexfatal( "error occurred when writing backtracking file" );

        else if ( fclose( backtrack_file ) )
            flexfatal( "error occurred when closing backtracking file" );
        }

    if ( printstats )
        {
        endtime = flex_gettime();

        fprintf( stderr, "%s version %s usage statistics:\n", program_name,
                 flex_version );
        fprintf( stderr, "  started at %s, finished at %s\n",
                 starttime, endtime );

        fprintf( stderr, "  scanner options: -" );

        if ( backtrack_report )
            putc( 'b', stderr );
        if ( ddebug )
            putc( 'd', stderr );
        if ( interactive )
            putc( 'I', stderr );
        if ( caseins )
            putc( 'i', stderr );
        if ( ! gen_line_dirs )
            putc( 'L', stderr );
        if ( performance_report )
            putc( 'p', stderr );
        if ( spprdflt )
            putc( 's', stderr );
        if ( use_stdout )
            putc( 't', stderr );
        if ( trace )
            putc( 'T', stderr );
        if ( printstats )
            putc( 'v', stderr );        /* always true! */
        if ( csize == 256 )
            putc( '8', stderr );

        fprintf( stderr, " -C" );

        if ( fulltbl )
            putc( 'f', stderr );
        if ( fullspd )
            putc( 'F', stderr );
        if ( useecs )
            putc( 'e', stderr );
        if ( usemecs )
            putc( 'm', stderr );

        if ( strcmp( skelname, ENQUOTE(DEFAULT_SKELETON_FILE) ) )
            fprintf( stderr, " -S%s", skelname );

        putc( '\n', stderr );

        fprintf( stderr, "  %d/%d NFA states\n", lastnfa, current_mns );
        fprintf( stderr, "  %d/%d DFA states (%d words)\n", lastdfa,
                 current_max_dfas, totnst );
        fprintf( stderr,
                 "  %d rules\n", num_rules - 1 /* - 1 for def. rule */ );

        if ( num_backtracking == 0 )
            fprintf( stderr, "  No backtracking\n" );
        else if ( fullspd || fulltbl )
            fprintf( stderr, "  %d backtracking (non-accepting) states\n",
                     num_backtracking );
        else
            fprintf( stderr, "  compressed tables always backtrack\n" );

        if ( bol_needed )
            fprintf( stderr, "  Beginning-of-line patterns used\n" );

        fprintf( stderr, "  %d/%d start conditions\n", lastsc,
                 current_max_scs );
        fprintf( stderr, "  %d epsilon states, %d double epsilon states\n",
                 numeps, eps2 );

        if ( lastccl == 0 )
            fprintf( stderr, "  no character classes\n" );
        else
            fprintf( stderr,
        "  %d/%d character classes needed %d/%d words of storage, %d reused\n",
                     lastccl, current_maxccls,
                     cclmap[lastccl] + ccllen[lastccl],
                     current_max_ccl_tbl_size, cclreuse );

        fprintf( stderr, "  %d state/nextstate pairs created\n", numsnpairs );
        fprintf( stderr, "  %d/%d unique/duplicate transitions\n",
                 numuniq, numdup );

        if ( fulltbl )
            {
            tblsiz = lastdfa * numecs;
            fprintf( stderr, "  %d table entries\n", tblsiz );
            }

        else
            {
            tblsiz = 2 * (lastdfa + numtemps) + 2 * tblend;

            fprintf( stderr, "  %d/%d base-def entries created\n",
                     lastdfa + numtemps, current_max_dfas );
            fprintf( stderr, "  %d/%d (peak %d) nxt-chk entries created\n",
                     tblend, current_max_xpairs, peakpairs );
            fprintf( stderr,
                     "  %d/%d (peak %d) template nxt-chk entries created\n",
                     numtemps * nummecs, current_max_template_xpairs,
                     numtemps * numecs );
            fprintf( stderr, "  %d empty table entries\n", nummt );
            fprintf( stderr, "  %d protos created\n", numprots );
            fprintf( stderr, "  %d templates created, %d uses\n",
                     numtemps, tmpuses );
            }

        if ( useecs )
            {
            tblsiz = tblsiz + csize;
            fprintf( stderr, "  %d/%d equivalence classes created\n",
                     numecs, csize );
            }

        if ( usemecs )
            {
            tblsiz = tblsiz + numecs;
            fprintf( stderr, "  %d/%d meta-equivalence classes created\n",
                     nummecs, csize );
            }

        fprintf( stderr, "  %d (%d saved) hash collisions, %d DFAs equal\n",
                 hshcol, hshsave, dfaeql );
        fprintf( stderr, "  %d sets of reallocations needed\n", num_reallocs );
        fprintf( stderr, "  %d total table entries needed\n", tblsiz );
        }

    exit( status );
}


/* flexinit - initialize flex
 *
 * synopsis
 *    int argc;
 *    char **argv;
 *    flexinit( argc, argv );
 */

void flexinit(int argc, char **argv)
{
    int i, sawcmpflag;
    char *arg, *flex_gettime(), *mktemp();

    printstats = syntaxerror = trace = spprdflt = interactive = caseins = false;
    backtrack_report = performance_report = ddebug = fulltbl = fullspd = false;
    yymore_used = continued_action = reject = false;
    yymore_really_used = reject_really_used = false;
    gen_line_dirs = usemecs = useecs = true;

    sawcmpflag = false;
    use_stdout = false;

    csize = DEFAULT_CSIZE;

    program_name = argv[0];

    /* read flags */
    for ( --argc, ++argv; argc ; --argc, ++argv )
        {
        if ( argv[0][0] != '-' || argv[0][1] == '\0' )
            break;

        arg = argv[0];

        for ( i = 1; arg[i] != '\0'; ++i )
            switch ( arg[i] )
                {
                case 'b':
                    backtrack_report = true;
                    break;

                case 'c':
                    fprintf( stderr,
        "%s: Assuming use of deprecated -c flag is really intended to be -C\n",
                             program_name );

                    /* fall through */

                case 'C':
                    if ( i != 1 )
                        flexerror( "-C flag must be given separately" );

                    if ( ! sawcmpflag )
                        {
                        useecs = false;
                        usemecs = false;
                        fulltbl = false;
                        sawcmpflag = true;
                        }

                    for ( ++i; arg[i] != '\0'; ++i )
                        switch ( arg[i] )
                            {
                            case 'e':
                                useecs = true;
                                break;

                            case 'F':
                                fullspd = true;
                                break;

                            case 'f':
                                fulltbl = true;
                                break;

                            case 'm':
                                usemecs = true;
                                break;

                            default:
                                lerrif( "unknown -C option '%c'",
                                        (int) arg[i] );
                                break;
                            }

                    goto get_next_arg;

                case 'd':
                    ddebug = true;
                    break;

                case 'f':
                    useecs = usemecs = false;
                    fulltbl = true;
                    break;

                case 'F':
                    useecs = usemecs = false;
                    fullspd = true;
                    break;

                case 'I':
                    interactive = true;
                    break;

                case 'i':
                    caseins = true;
                    break;

                case 'L':
                    gen_line_dirs = false;
                    break;

                case 'n':
                    /* stupid do-nothing deprecated option */
                    break;

                case 'o':
                    if ( i != 1 )
                        flexerror( "-o flag must be given separately" );

                    outfile = arg + i + 1;
                    goto get_next_arg;

                case 'p':
                    performance_report = true;
                    break;

                case 'S':
                    if ( i != 1 )
                        flexerror( "-S flag must be given separately" );

                    skelname = arg + i + 1;
                    goto get_next_arg;

                case 's':
                    spprdflt = true;
                    break;

                case 't':
                    use_stdout = true;
                    break;

                case 'T':
                    trace = true;
                    break;

                case 'v':
                    printstats = true;
                    break;

                case '8':
                    csize = CSIZE;
                    break;

                default:
                    lerrif( "unknown flag '%c'", (int) arg[i] );
                    break;
                }

get_next_arg: /* used by -C and -S flags in lieu of a "continue 2" control */
        ;
        }

    if ( (fulltbl || fullspd) && usemecs )
        flexerror( "full table and -Cm don't make sense together" );

    if ( (fulltbl || fullspd) && interactive )
        flexerror( "full table and -I are (currently) incompatible" );

    if ( fulltbl && fullspd )
        flexerror( "full table and -F are mutually exclusive" );

    if ( ! skelname )
        {
        static char skeleton_name_storage[400];

        skelname = skeleton_name_storage;
        (void) strcpy( skelname, ENQUOTE(DEFAULT_SKELETON_FILE) );
        }

    if ( ! use_stdout )
        {
        FILE *prev_stdout = freopen( outfile, "w", stdout );

        if ( prev_stdout == NULL )
            lerrsf( "could not create %s", outfile );

        outfile_created = 1;
        }

    num_input_files = argc;
    input_files = argv;
    set_input_file( num_input_files > 0 ? input_files[0] : NULL );

    if ( backtrack_report )
        {
#ifndef SHORT_FILE_NAMES
        backtrack_file = fopen( "lex.backtrack", "w" );
#else
        backtrack_file = fopen( "lex.bck", "w" );
#endif

        if ( backtrack_file == NULL )
            flexerror( "could not create lex.backtrack" );
        }

    else
        backtrack_file = NULL;


    lastccl = 0;
    lastsc = 0;

    /* initialize the statistics */
    starttime = flex_gettime();

    if ( (skelfile = fopen( skelname, "r" )) == NULL )
        lerrsf( "can't open skeleton file %s", skelname );

    if ( ( temp_action_file = epicsTempFile () ) == NULL )
    {
        lerrsf( "can't create temporary action file", "" );
    }

    lastdfa = lastnfa = num_rules = numas = numsnpairs = tmpuses = 0;
    numecs = numeps = eps2 = num_reallocs = hshcol = dfaeql = totnst = 0;
    numuniq = numdup = hshsave = eofseen = datapos = dataline = 0;
    num_backtracking = onesp = numprots = 0;
    variable_trailing_context_rules = bol_needed = false;

    linenum = sectnum = 1;
    firstprot = NIL;

    /* used in mkprot() so that the first proto goes in slot 1
     * of the proto queue
     */
    lastprot = 1;

    if ( useecs )
        { /* set up doubly-linked equivalence classes */
        /* We loop all the way up to csize, since ecgroup[csize] is the
         * position used for NUL characters
         */
        ecgroup[1] = NIL;

        for ( i = 2; i <= csize; ++i )
            {
            ecgroup[i] = i - 1;
            nextecm[i - 1] = i;
            }

        nextecm[csize] = NIL;
        }

    else
        { /* put everything in its own equivalence class */
        for ( i = 1; i <= csize; ++i )
            {
            ecgroup[i] = i;
            nextecm[i] = BAD_SUBSCRIPT; /* to catch errors */
            }
        }

    set_up_initial_allocations();
}


/* readin - read in the rules section of the input file(s)
 *
 * synopsis
 *    readin();
 */

void readin(void)
{
    skelout();

    if ( ddebug )
        puts( "#define FLEX_DEBUG" );

    if ( csize == 256 )
        puts( "#define YY_CHAR unsigned char" );
    else
        puts( "#define YY_CHAR char" );

    line_directive_out( stdout );

    if ( yyparse() )
        {
        pinpoint_message( "fatal parse error" );
        flexend( 1 );
        }

    if ( xlation )
        {
        numecs = ecs_from_xlation( ecgroup );
        useecs = true;
        }

    else if ( useecs )
        numecs = cre8ecs( nextecm, ecgroup, csize );

    else
        numecs = csize;

    /* now map the equivalence class for NUL to its expected place */
    ecgroup[0] = ecgroup[csize];
    NUL_ec = abs( ecgroup[0] );

    if ( useecs )
        ccl2ecl();
}



/* set_up_initial_allocations - allocate memory for internal tables */

void set_up_initial_allocations(void)
{
    current_mns = INITIAL_MNS;
    firstst = allocate_integer_array( current_mns );
    lastst = allocate_integer_array( current_mns );
    finalst = allocate_integer_array( current_mns );
    transchar = allocate_integer_array( current_mns );
    trans1 = allocate_integer_array( current_mns );
    trans2 = allocate_integer_array( current_mns );
    accptnum = allocate_integer_array( current_mns );
    assoc_rule = allocate_integer_array( current_mns );
    state_type = allocate_integer_array( current_mns );

    current_max_rules = INITIAL_MAX_RULES;
    rule_type = allocate_integer_array( current_max_rules );
    rule_linenum = allocate_integer_array( current_max_rules );

    current_max_scs = INITIAL_MAX_SCS;
    scset = allocate_integer_array( current_max_scs );
    scbol = allocate_integer_array( current_max_scs );
    scxclu = allocate_integer_array( current_max_scs );
    sceof = allocate_integer_array( current_max_scs );
    scname = allocate_char_ptr_array( current_max_scs );
    actvsc = allocate_integer_array( current_max_scs );

    current_maxccls = INITIAL_MAX_CCLS;
    cclmap = allocate_integer_array( current_maxccls );
    ccllen = allocate_integer_array( current_maxccls );
    cclng = allocate_integer_array( current_maxccls );

    current_max_ccl_tbl_size = INITIAL_MAX_CCL_TBL_SIZE;
    ccltbl = allocate_character_array( current_max_ccl_tbl_size );

    current_max_dfa_size = INITIAL_MAX_DFA_SIZE;

    current_max_xpairs = INITIAL_MAX_XPAIRS;
    nxt = allocate_integer_array( current_max_xpairs );
    chk = allocate_integer_array( current_max_xpairs );

    current_max_template_xpairs = INITIAL_MAX_TEMPLATE_XPAIRS;
    tnxt = allocate_integer_array( current_max_template_xpairs );

    current_max_dfas = INITIAL_MAX_DFAS;
    base = allocate_integer_array( current_max_dfas );
    def = allocate_integer_array( current_max_dfas );
    dfasiz = allocate_integer_array( current_max_dfas );
    accsiz = allocate_integer_array( current_max_dfas );
    dhash = allocate_integer_array( current_max_dfas );
    dss = allocate_int_ptr_array( current_max_dfas );
    dfaacc = allocate_dfaacc_union( current_max_dfas );

    nultrans = (int *) 0;
}