Plan 9 from Bell Labs’s /usr/web/sources/contrib/steve/root/sys/src/cmd/indent/lexi.c

Copyright © 2021 Plan 9 Foundation.
Distributed under the MIT License.
Download the Plan 9 distribution.


/* Copyright (c) 1994, Joseph Arceneaux.  All rights reserved
 *
 * Copyright (c) 1992, Free Software Foundation, Inc.  All rights reserved.
 *
 * Copyright (c) 1985 Sun Microsystems, Inc. Copyright (c) 1980 The Regents
 * of the University of California. Copyright (c) 1976 Board of Trustees of
 * the University of Illinois. All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that
 * the above copyright notice and this paragraph are duplicated in all such
 * forms and that any documentation, advertising materials, and other
 * materials related to such distribution and use acknowledge that the
 * software was developed by the University of California, Berkeley, the
 * University of Illinois, Urbana, and Sun Microsystems, Inc.  The name of
 * either University or Sun Microsystems may not 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 MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */


/* Here we have the token scanner for indent.  It scans off one token and
 * puts it in the global variable "token".  It returns a code, indicating the
 * type of token scanned. */

#include "sys.h"
#include <ctype.h>
#if defined (HAVE_UNISTD_H)
#include <unistd.h>
#endif
#include <string.h>
#include "indent.h"
#include "globs.h"

RCSTAG_CC ("$Id: lexi.c,v 1.37 2002/08/04 17:08:41 david Exp $");

/* Stuff that needs to be shared with the rest of indent. Documented in
 * indent.h.  */
char *token;
char *token_end;

#define alphanum 1
#define opchar 3

typedef struct templ
{
  char     * rwd;
  rwcodes_ty rwcode;
} templ_ty;

/* Pointer to a vector of keywords specified by the user.  */
static templ_ty *user_specials = 0;

/* Allocated size of user_specials.  */
static unsigned int user_specials_max;

/* Index in user_specials of the first unused entry.  */
static unsigned int user_specials_idx;

char chartype[] =
{
    /* this is used to facilitate the decision of
     * what type (alphanumeric, operator) each
     * character is */
#ifndef CHARSET_EBCDIC

  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 3, 0, 0, 1, 3, 3, 0,
  0, 0, 3, 3, 0, 3, 0, 3,
  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 0, 0, 3, 3, 3, 3,
  0, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 0, 0, 0, 3, 1,
  0, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 1, 1, 1, 1, 1,
  1, 1, 1, 0, 3, 0, 3, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0,

#else				/* CHARSET_EBCDIC */

/*
 * The following table was generated by the program given at the end
 */

  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*| .......| */
  0, 0, 0, 0, 3, 0, 3, 3,	/*|..`.<(+|| */
  3, 0, 0, 0, 0, 0, 0, 0,	/*|&.......| */
  0, 0, 3, 1, 3, 0, 0, 0,	/*|..!$*);.| */
  3, 3, 0, 0, 0, 0, 0, 0,	/*|-/......| */
  0, 0, 3, 0, 3, 1, 3, 3,	/*|..^,%_>?| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 3, 0,	/*|..:#@'="| */
  0, 1, 1, 1, 1, 1, 1, 1,	/*|.abcdefg| */
  1, 1, 0, 0, 0, 0, 0, 0,	/*|hi......| */
  0, 1, 1, 1, 1, 1, 1, 1,	/*|.jklmnop| */
  1, 1, 0, 0, 0, 0, 0, 0,	/*|qr......| */
  0, 0, 1, 1, 1, 1, 1, 1,	/*|..stuvwx| */
  1, 1, 0, 0, 0, 0, 0, 0,	/*|yz......| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|........| */
  0, 0, 0, 0, 0, 0, 0, 0,	/*|...[\]..| */
  0, 1, 1, 1, 1, 1, 1, 1,	/*|.ABCDEFG| */
  1, 1, 0, 0, 0, 0, 0, 0,	/*|HI......| */
  0, 1, 1, 1, 1, 1, 1, 1,	/*|.JKLMNOP| */
  1, 1, 0, 0, 0, 0, 0, 0,	/*|QR......| */
  0, 0, 1, 1, 1, 1, 1, 1,	/*|..STUVWX| */
  1, 1, 0, 0, 0, 0, 0, 0,	/*|YZ......| */
  1, 1, 1, 1, 1, 1, 1, 1,	/*|01234567| */
  1, 1, 0, 0, 0, 0, 0, 3,	/*|89.{.}.~| */
#endif				/* CHARSET_EBCDIC */
};

/*
 * The table above was generated by the following program from
 * the ASCII version of the chartype[] array above, where the
 * unsigned char os_toascii[] array can be found in the source
 * for the Apache Web Server version 1.3.x, in the directories...
 *  src/os/bs2000/ebcdic.c    for the SIEMENS BS2000 mainframes,
 *  src/os/tpf/ebcdic.c       for the IBM TPF server line.
 * The following table was created for BS2000 EBCDIC character set,
 * but the few non-zero places should be compatible with IBM's EBCDIC.
 */
#if 0
int main (void)
{
    const int GAP = 8;
    int i, j;

    for (i = 0; i < 256; i += GAP)
    {
        printf ("  ");
        for (j = 0; j < GAP; ++j)
	{
            printf ("%d, ", chartype[os_toascii[i + j]]);
	}
        
        printf (" /*|");
        
        for (j = 0; j < GAP; ++j)
	{
            printf ("%c", isprint (i + j) ? (i + j) : '.');
	}
        
        printf ("|*/\n");
    }
    return 0;
}
#endif

/* Include code generated by gperf */
#ifdef __GNUC__
__inline
#endif
templ_ty *is_reserved (register const char *str, register unsigned int len);

#include "gperf.c"

/* Include code generated by gperf for C++ keyword set */
#undef MIN_HASH_VALUE		/* remove old defs */
#undef MAX_HASH_VALUE
#undef TOTAL_KEYWORDS
#undef MIN_WORD_LENGTH
#undef MAX_WORD_LENGTH

#ifdef __GNUC__
__inline
#endif
templ_ty *is_reserved_cc (register const char *str, register unsigned int len);

#include "gperf-cc.c"

codes_ty lexi (void)
{
    int             unary_delim;/* this is set to 1 if the current token
                                 * forces a following operator to be unary */
    static codes_ty last_code;	/* the last token type returned */
    static int      l_struct;   /* set to 1 if the last token was 'struct' */
    static int      l_enum;	/* set to 1 if the last token was `enum' */
    codes_ty        code;	/* internal code to be returned */
    char            qchar;      /* the delimiter character for a string */

    static int      count;	/* debugging counter */

    count++;

    unary_delim = false;
    
    /* tell world that this token started in column 1 iff the last
     * thing scanned was nl */
    
    parser_state_tos->col_1       = parser_state_tos->last_nl;
    parser_state_tos->last_saw_nl = parser_state_tos->last_nl;
    parser_state_tos->last_nl     = false;

    if (buf_ptr >= buf_end)
    {
        fill_buffer ();
    }

    if (*buf_ptr == ' ' || *buf_ptr == TAB)
    {
        parser_state_tos->col_1 = false;

        skip_buffered_space(); /* adjusts buf_ptr */
    }

    /* INCREDIBLY IMPORTANT WARNING!!!
     *
     * Note that subsequent calls to `fill_buffer ()' may switch `buf_ptr'
     * to a different buffer.  Thus when `token_end' gets set later, it
     * may be pointing into a different buffer than `token'. */
    
    token = buf_ptr;

    /* Scan an alphanumeric token */
    
    if ((!((buf_ptr[0] == 'L') &&
           ((buf_ptr[1] == '"') || (buf_ptr[1] == '\''))) &&
         (chartype[0xff & (int) *buf_ptr] == alphanum)) ||
        ((buf_ptr[0] == '.') && isdigit (buf_ptr[1])))
    {
        /* we have a character or number */
        templ_ty *p;

        if (isdigit (*buf_ptr) ||
            ((buf_ptr[0] == '.') && isdigit (buf_ptr[1])))
	{
            int seendot = 0, seenexp = 0;

            if ((*buf_ptr == '0') && ((buf_ptr[1] == 'x') || (buf_ptr[1] == 'X')))
	    {
                buf_ptr += 2;
                while (isxdigit (*buf_ptr))
		{
                    buf_ptr++;
		}
	    }
            else
                while (1)
                {
                    if (*buf_ptr == '.')
                    {
                        if (seendot)
                        {
                            break;
                        }
                        else
                        {
                            seendot++;
                        }
                    }

                    buf_ptr++;
                    
                    if (!isdigit (*buf_ptr) && *buf_ptr != '.')
                    {
                        if ((*buf_ptr != 'E' && *buf_ptr != 'e') || seenexp)
                        {
                            break;
                        }
                        else
                        {
                            seenexp++;
                            seendot++;
                            buf_ptr++;

                            if (*buf_ptr == '+' || *buf_ptr == '-')
                            {
                                buf_ptr++;
                            }
                        }
                    }
                }

            if (*buf_ptr == 'F' || *buf_ptr == 'f' || *buf_ptr == 'i' || *buf_ptr == 'j')
            {
                buf_ptr++;
            }
            else
	    {
                while (*buf_ptr == 'U' || *buf_ptr == 'u' || *buf_ptr == 'L' || *buf_ptr == 'l')
                {
                    buf_ptr++;
                }
	    }
	}
        else
            while (chartype[0xff & (int) *buf_ptr] == alphanum)
            {			/* copy it over */
                buf_ptr++;

                if (buf_ptr >= buf_end)
                {
                    fill_buffer ();
                }
            }

        token_end = buf_ptr;

        if (token_end - token == 13 && !strncmp (token, "__attribute__", 13))
	{
            last_code = decl;
            parser_state_tos->last_u_d = true;
            return (attribute);
	}

        skip_buffered_space(); /* adjusts buf_ptr */

        /* Handle operator declarations. */

        if (token_end - token == 8 && !strncmp (token, "operator", 8))
        {
            while (chartype[0xff & (int) *buf_ptr] == opchar)
	    {
                buf_ptr++;
                
                if (buf_ptr >= buf_end)
                {
                    fill_buffer ();
                }
	    }

            token_end = buf_ptr;

            skip_buffered_space(); /* adjusts buf_ptr */
            
	}

        parser_state_tos->its_a_keyword = false;
        parser_state_tos->sizeof_keyword = false;

        /* if last token was 'struct', then this token should be treated
           as a declaration */
        if (l_struct)
	{
            l_struct = false;
            last_code = ident;
            parser_state_tos->last_u_d = true;
            
            if (parser_state_tos->last_token == cpp_operator)
            {
                return overloaded;
            }
            return (decl);
	}

        /* Operator after indentifier is binary */

        parser_state_tos->last_u_d = false;
        last_code = ident;

        /* Check whether the token is a reserved word.  Use perfect hashing... */
        
        if (settings.c_plus_plus)
        {
            p = is_reserved_cc (token, token_end - token);
        }
        else
        {
            p = is_reserved (token, token_end - token);
        }

        if ((p == NULL) && (user_specials != 0))
	{
            for (p = &user_specials[0]; p < &user_specials[0] + user_specials_idx; p++)
	    {
                char *q = token;
                char *r = p->rwd;

                /* This string compare is a little nonstandard because token
                 * ends at the character before token_end and p->rwd is
                 * null-terminated.  */
                
                while (1)
		{
                    /* If we have come to the end of both the keyword in
                     * user_specials and the keyword in token they are equal.  */
                    
                    if (q >= token_end && !*r)
                    {
                        goto found_keyword;
                    }

                    /* If we have come to the end of just one, they are not
                     * equal.  */
                    
                    if (q >= token_end || !*r)
                    {
                        break;
                    }

                    /* If the characters in corresponding characters are not
                     * equal, the strings are not equal.  */
                    
                    if (*q++ != *r++)
                    {
                        break;
                    }
		}
	    }

            /* Didn't find anything in user_specials.  */

            p = NULL;
	}

	found_keyword:

        if (p)
	{			/* we have a keyword */
            codes_ty value;

            value = ident;
            parser_state_tos->its_a_keyword = true;
            parser_state_tos->last_u_d      = true;
            parser_state_tos->last_rw       = p->rwcode;
            parser_state_tos->last_rw_depth = parser_state_tos->paren_depth;
            
            switch (p->rwcode)
	    {
                case rw_operator:	/* C++ operator overloading. */
                    value = cpp_operator;
                    parser_state_tos->in_parameter_declaration = 1;
                    break;
                case rw_switch:	/* it is a switch */
                    value = (swstmt);
                    break;
                case rw_case:	/* a case or default */
                    value = (casestmt);
                    break;
                case rw_enum:
                    l_enum = true;	/* reset on '(' ')' '{' '}' or ';' */
                    /* fall through */
                case rw_struct_like:	/* a "struct" */
                    if (parser_state_tos->p_l_follow && !(parser_state_tos->noncast_mask & 1 << parser_state_tos->p_l_follow))
                        /* inside parens: cast */
                    {
                        parser_state_tos->cast_mask |= 1 << parser_state_tos->p_l_follow;
                        break;
                    }

                    l_struct = true;

                    /* Next time around, we will want to know that we have had a
                       'struct' */
                case rw_decl:	/* one of the declaration keywords */
                    if (parser_state_tos->p_l_follow && !(parser_state_tos->noncast_mask & 1 << parser_state_tos->p_l_follow))
                        /* inside parens: cast */
                    {
                        parser_state_tos->cast_mask |= 1 << parser_state_tos->p_l_follow;
                        break;
                    }
                    
                    last_code = decl;
                    value = (decl);
                    break;

                case rw_sp_paren:	/* if, while, for */
                    value = (sp_paren);
                    if (*token == 'i' && parser_state_tos->last_token == sp_else)
                    {
                        parser_state_tos->i_l_follow -= settings.ind_size;
                    }
                    
                    break;

                case rw_sp_nparen:	/* do */
                    value = (sp_nparen);
                    break;

                case rw_sp_else:	/* else */
                    value = (sp_else);
                    break;

                case rw_sizeof:
                    parser_state_tos->sizeof_keyword = true;
                    value = (ident);
                    break;

                case rw_return:
                case rw_break:
                default:		/* all others are treated like any other
                                           identifier */
                    value = (ident);
	    }			/* end of switch */

            if (parser_state_tos->last_token == cpp_operator)
            {
                return overloaded;
            }
            
            return value;
	}			/* end of if (found_it) */
        else if ((*buf_ptr == '(') && (parser_state_tos->tos <= 1) &&
                 (parser_state_tos->ind_level == 0) &&
                 (parser_state_tos->paren_depth == 0))
	{
            /* We have found something which might be the name in a function
             * definition.  */
            
            char *tp;
            int paren_count = 1;

            /* If the return type of this function definition was not defined
             * with a -T commandline option, then the output of indent would
             * alternate on subsequent calls.  In order to avoid that we try
             * to detect that case here and make a minimal change to cause
             * the correct behaviour.
             */
            
            if (parser_state_tos->last_token == ident && parser_state_tos->last_saw_nl)
            {
                parser_state_tos->in_decl = true;
            }

            /* Skip to the matching ')'.  */
            
            for (tp = buf_ptr + 1; (paren_count > 0) && (tp < in_prog + in_prog_size); tp++)
	    {
                if (*tp == '(')
                {
                    paren_count++;
                }
                
                if (*tp == ')')
                {
                    paren_count--;
                }
                
                /* Can't occur in parameter list; this way we don't search the
                 * whole file in the case of unbalanced parens.  */
                
                if (*tp == ';')
                {
                    goto not_proc;
                }
	    }

            if (paren_count == 0)
	    {
                parser_state_tos->procname = token;
                parser_state_tos->procname_end = token_end;

                while (isspace (*tp))
                {
                    tp++;
                }

                if ((*tp == '_') && (in_prog + in_prog_size - tp >= 13) &&
                    !strncmp (tp, "__attribute__", 13))
		{
                    /* Found an __attribute__ after a function declaration */
                    /* Must be a declaration */
		}
                else
                {
                    /* If the next char is ';' or ',' or '(' we have a function
                     * declaration, not a definition.
                     *
                     * I've added '=' to this list to keep from breaking
                     * a non-valid C macro from libc.  -jla */
                    
                    if (*tp != ';' && *tp != ',' && *tp != '(' && *tp != '=')
                    {
                        parser_state_tos->in_parameter_declaration = 1;
                    }
                }
	    }

	not_proc:;
	}
        else if ((*buf_ptr == ':') && (*(buf_ptr + 1) == ':') &&
                 (parser_state_tos->tos <= 1) &&
                 (parser_state_tos->ind_level == 0) &&
                 (parser_state_tos->paren_depth == 0))
	{
            parser_state_tos->classname = token;
            parser_state_tos->classname_end = token_end;
	}
        
        /* The following hack attempts to guess whether or not the
         * current token is in fact a declaration keyword -- one that
         * has been typedef'd */
        
        else if ( ( ((*buf_ptr == '*') && (buf_ptr[1] != '=')) ||
                    isalpha (*buf_ptr) || (*buf_ptr == '_')) &&
                  !parser_state_tos->p_l_follow && !parser_state_tos->block_init &&
                  ( (parser_state_tos->last_token == rparen)    ||
                    (parser_state_tos->last_token == semicolon) ||
                    (parser_state_tos->last_token == rbrace)    ||
                    (parser_state_tos->last_token == decl)      ||
                    (parser_state_tos->last_token == lbrace)    ||
                    (parser_state_tos->last_token == start_token)))
	{
            parser_state_tos->its_a_keyword = true;
            parser_state_tos->last_u_d = true;
            last_code = decl;
            
            if (parser_state_tos->last_token == cpp_operator)
            {
                return overloaded;
            }

            return decl;
	}

        if (last_code == decl)
        {
            /* if this is a declared variable, then
               following sign is unary */
            parser_state_tos->last_u_d = true;	/* will make "int a -1" work */
        }
        
        last_code = ident;
        
        if (parser_state_tos->last_token == cpp_operator)
        {
            return overloaded;
        }

        return (ident);		/* the ident is not in the list */
    }				/* end of procesing for alpanum character */

    /* Scan a non-alphanumeric token */

    /* If it is not a one character token, token_end will get changed later.  */

    token_end = buf_ptr + 1;

    /* THIS MAY KILL YOU!!!
     *
     * Note that it may be possible for this to kill us--if `fill_buffer'
     * at any time switches `buf_ptr' to the other input buffer, `token'
     * and `token_end' will point to different storage areas!!! */
    
    if (++buf_ptr >= buf_end)
    {
        fill_buffer ();
    }

    /* If it is a backslash new-line, just eat the backslash */

    if ((*token == '\\') && (buf_ptr[0] == EOL))
    {
        token = buf_ptr;
        
        if (++buf_ptr >= buf_end)
        {
            fill_buffer ();
        }
    }

    switch (*token)
    {
        case '\0':
            code = code_eof;
            break;

        case EOL:
            parser_state_tos->matching_brace_on_same_line = -1;
            unary_delim = parser_state_tos->last_u_d;
            parser_state_tos->last_nl = true;
            code = newline;
            break;

            /* Handle wide strings and chars. */
        case 'L':
            if (buf_ptr[0] != '"' && buf_ptr[0] != '\'')
            {
                token_end = buf_ptr;
                code = ident;
                break;
            }

            qchar = buf_ptr[0];
            buf_ptr++;
            goto handle_string;

        case '\'':			/* start of quoted character */
        case '"':			/* start of string */
            qchar = *token;

    handle_string:
            /* Find out how big the literal is so we can set token_end.  */

            /* Invariant:  before loop test buf_ptr points to the next
             * character that we have not yet checked. */
            
            while ((*buf_ptr != qchar) && (*buf_ptr != 0)) /* && *buf_ptr != EOL) */
            {
                if (*buf_ptr == EOL)
                {
                    ++line_no;
                }
                    
                if (*buf_ptr == '\\')
                {
                    buf_ptr++;
                    
                    if (buf_ptr >= buf_end)
                    {
                        fill_buffer ();
                    }
                    
                    if (*buf_ptr == EOL)
                    {
                        ++line_no;
                    }
                    
                    if (*buf_ptr == 0)
                    {
                        break;
                    }
                }

                buf_ptr++;
                
                if (buf_ptr >= buf_end)
                {
                    fill_buffer ();
                }
            }

            if (*buf_ptr == EOL || *buf_ptr == 0)
            {
                WARNING ((qchar == '\'' ? _("Unterminated character constant") :
                                          _("Unterminated string constant")), 0, 0);
            }
            else
            {
                /* Advance over end quote char.  */
                buf_ptr++;
                
                if (buf_ptr >= buf_end)
                {
                    fill_buffer ();
                }
            }

            token_end = buf_ptr;
            code = ident;
            break;

        case ('('):
            l_enum = false;
            unary_delim = true;
            code = lparen;
            break;

        case ('['):
            if (parser_state_tos->in_or_st)
            {
                parser_state_tos->in_or_st++;
            }
            
            unary_delim = true;
            code = lparen;
            break;

        case (')'):
            l_enum = false;
            code = rparen;
            break;

        case (']'):
            if (parser_state_tos->in_or_st > 1)
            {
                parser_state_tos->in_or_st--;
            }
            
            code = rparen;
            break;

        case '#':
            unary_delim = parser_state_tos->last_u_d;
            code = preesc;

            /* Make spaces between '#' and the directive be part of
               the token if user specified "-lps" */
            if (settings.leave_preproc_space)
            {
                while (*buf_ptr == ' ' && buf_ptr < buf_end)
                {
                    buf_ptr++;
                }
                
                token_end = buf_ptr;
            }
            break;

        case '?':
            unary_delim = true;
            code = question;
            break;

        case (':'):
            /* Deal with C++ class::method */
            
            if (*buf_ptr == ':')
            {
                code = doublecolon;
                buf_ptr++;
                token_end = buf_ptr;
                break;
            }

            code = colon;
            unary_delim = true;
            if (squest && *e_com != ' ')
            {
                if (e_code == s_code)
                {
                    parser_state_tos->want_blank = false;
                }
                
                else
                {
                    parser_state_tos->want_blank = true;
                }
            }
            break;

        case (';'):
            l_enum = false;
            unary_delim = true;
            code = semicolon;
            break;

        case ('{'):
            if (parser_state_tos->matching_brace_on_same_line < 0)
            {
                parser_state_tos->matching_brace_on_same_line = 1;
            }
            else
            {
                parser_state_tos->matching_brace_on_same_line++;
            }
            
            if (l_enum)
            {
                /* Keep all variables in the same column:
                 *   ONE,
                 *   TWO, etc
                 * instead of
                 *   ONE,
                 *     TWO,
                 * Use a special code for `block_init' however, because we still
                 * want to do the line breaks when `settings.braces_on_struct_decl_line'
                 * is not set.
                 */
                parser_state_tos->block_init = 2;
                parser_state_tos->block_init_level = 0;
                l_enum = false;
            }
            
            unary_delim = true;
            code = lbrace;
            break;

        case ('}'):
            parser_state_tos->matching_brace_on_same_line--;
            l_enum = false;
            unary_delim = true;
            code = rbrace;
            break;

        case 014:			/* a form feed */
            unary_delim = parser_state_tos->last_u_d;
            parser_state_tos->last_nl = true;	/* remember this so we can set
                                                   'parser_state_tos->col_1' right */
            code = form_feed;
            break;

        case (','):
            unary_delim = true;
            code = comma;
            break;

        case '.':
            if (parser_state_tos->in_decl && 
                (buf_ptr[0] == '.') && 
                (buf_ptr[1] == '.'))
            {
                /* check for '...' in a declaration */
                if ((buf_ptr += 2) >= buf_end)
                {
                    fill_buffer ();
                }
                
                unary_delim = true;
                code = decl;
                token_end = buf_ptr;
                break;
            }
            unary_delim = false;
            code = struct_delim;
            
            if (*buf_ptr == '*')	/* object .* pointer-to-member */
            {
                ++buf_ptr;
                token_end = buf_ptr;
            }
            break;

        case '-':
        case '+':			/* check for -, +, --, ++ */
            code = (parser_state_tos->last_u_d ? unary_op : binary_op);
            unary_delim = true;

            if (*buf_ptr == token[0])
            {
                /* check for doubled character */
                buf_ptr++;
                /* buffer overflow will be checked at end of loop */
                if (last_code == ident || last_code == rparen)
                {
                    code = (parser_state_tos->last_u_d ? unary_op : postop);
                    /* check for following ++ or -- */
                    unary_delim = false;
                }
            }
            else if (*buf_ptr == '=')
            {
                /* check for operator += */
                buf_ptr++;
            }
            else if (*buf_ptr == '>')
            {
                /* check for operator -> */
                buf_ptr++;
                code = struct_delim;
                /* check for operator ->* */

                if (*buf_ptr == '*')
                {
                    buf_ptr++;
                }
            }

            token_end = buf_ptr;
            break;			/* buffer overflow will be checked at end of
                                           switch */

        case '=':
            if (parser_state_tos->in_or_st && 
                (parser_state_tos->last_token != cpp_operator))
            {
                parser_state_tos->block_init = 1;
                parser_state_tos->block_init_level = 0;
            }

            if (*buf_ptr == '=')	/* == */
            {
                buf_ptr++;
            }
            else if ((*buf_ptr == '-') ||
                     (*buf_ptr == '+') ||
                     (*buf_ptr == '*') ||
                     (*buf_ptr == '&'))
            {
                /* Something like x=-1, which can mean x -= 1 ("old style" in K&R1)
                 * or x = -1 (ANSI).  Note that this is only an ambiguity if the
                 * character can also be a unary operator.  If not, just produce
                 * output code that produces a syntax error (the theory being that
                 * people want to detect and eliminate old style assignments but
                 * they don't want indent to silently change the meaning of their
                 * code).  */
                
                WARNING (_("old style assignment ambiguity in \"=%c\".  Assuming \"= %c\"\n"),
                         (unsigned long) *((unsigned char *) buf_ptr), (unsigned long) *((unsigned char *) buf_ptr));
            }

            code = binary_op;
            unary_delim = true;
            token_end = buf_ptr;
            break;
            /* can drop thru!!! */

        case '>':
        case '<':
        case '!':
            /* ops like <, <<, <=, !=, <<=, etc */
            /* This will of course scan sequences like "<=>", "!=>", "<<>", etc. as
             * one token, but I don't think that will cause any harm.  */
            /* in C++ mode also scan <?[=], >?[=] GNU C++ operators 
             * maybe some flag to them ? */
            
            while (*buf_ptr == '>' || *buf_ptr == '<' || *buf_ptr == '=' || (settings.c_plus_plus && *buf_ptr == '?'))
            {
                if (++buf_ptr >= buf_end)
                {
                    fill_buffer ();
                }
                
                if (*buf_ptr == '=')
                {
                    if (++buf_ptr >= buf_end)
                    {
                        fill_buffer ();
                    }
                }
            }

            code = (parser_state_tos->last_u_d ? unary_op : binary_op);
            unary_delim = true;
            token_end = buf_ptr;
            break;

        default:
            if (token[0] == '/' && (*buf_ptr == '*' || *buf_ptr == '/'))
            {
                /* A C or C++ comment */

                if (*buf_ptr == '*')
                {
                    code = comment;
                }
                else
                {
                    code = cplus_comment;
                }

                if (++buf_ptr >= buf_end)
                {
                    fill_buffer ();
                }

                if (code == comment)
                {
                    /* Threat comments of type / *UPPERCASE* / not as comments */
                    char *p = buf_ptr;

                    while (isupper (*p++))
                    {
                        /* There is always at least one
                         * newline in the buffer; so no
                         * need to check for buf_end. */
                    }
                    
                    if (p < buf_end && p[-1] == '*' && *p == '/')
                    {
                        buf_ptr = p + 1;
                        code = ident;
                        parser_state_tos->want_blank = true;
                    }
                }
                
                unary_delim = parser_state_tos->last_u_d;
            }
            else if (parser_state_tos->last_token == cpp_operator)
            {
                /* For C++ overloaded operators. */
                code = overloaded;
                last_code = overloaded;
            }
            else
            {
                while (*(buf_ptr - 1) == *buf_ptr || *buf_ptr == '=')
                {
                    /* handle ||, &&, etc, and also things as in int *****i */
                    if (++buf_ptr >= buf_end)
                    {
                        fill_buffer ();
                    }
                }
                code = (parser_state_tos->last_u_d ? unary_op : binary_op);
                unary_delim = true;
            }

            token_end = buf_ptr;

    }				/* end of switch */

    if (code != newline)
    {
        l_struct = false;
        last_code = code;
    }

    if (buf_ptr >= buf_end)
    {
        fill_buffer ();
    }
    
    parser_state_tos->last_u_d = unary_delim;

    if (parser_state_tos->last_token == cpp_operator)
    {
        return overloaded;
    }
    
    return (code);
}

/* Add the given keyword to the keyword table, using val as
 * the keyword type */

void addkey (
    char *key,
    rwcodes_ty val)
{
    templ_ty *p;

    /* Check to see whether key is a reserved word or not. */
    if ( (settings.c_plus_plus  && is_reserved_cc (key, strlen (key)) != 0) ||
         (!settings.c_plus_plus && is_reserved (key, strlen (key)) != 0))
    {
        return;
    }

    if (user_specials == 0)
    {
        user_specials = (templ_ty *) xmalloc (5 * sizeof (templ_ty));
        user_specials_max = 5;
        user_specials_idx = 0;
    }
    else if (user_specials_idx == user_specials_max)
    {
        user_specials_max += 5;
        user_specials = (templ_ty *) xrealloc ((char *) user_specials, user_specials_max * sizeof (templ_ty));
    }

    p = &user_specials[user_specials_idx++];
    p->rwd = key;
    p->rwcode = val;
    return;
}

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