indent/lexi.c

/*  $OpenBSD: lexi.c,v 1.20 2016/06/06 06:43:03 tobiasu Exp $   */

/*
 * Copyright (c) 1980, 1993
 *  The Regents of the University of California.
 * Copyright (c) 1976 Board of Trustees of the University of Illinois.
 * Copyright (c) 1985 Sun Microsystems, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. 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 BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * 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 <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <err.h>
#include "indent_globs.h"
#include "indent_codes.h"

#define alphanum 1
#define opchar 3

struct templ {
    char       *rwd;
    int         rwcode;
};

struct templ specialsinit[] = {
    { "switch", 1 },
    { "case", 2 },
    { "break", 0 },
    { "struct", 3 },
    { "union", 3 },
    { "enum", 3 },
    { "default", 2 },
    { "int", 4 },
    { "char", 4 },
    { "float", 4 },
    { "double", 4 },
    { "long", 4 },
    { "short", 4 },
    { "typedef", 4 },
    { "unsigned", 4 },
    { "register", 4 },
    { "static", 4 },
    { "global", 4 },
    { "extern", 4 },
    { "void", 4 },
    { "goto", 0 },
    { "return", 0 },
    { "if", 5 },
    { "while", 5 },
    { "for", 5 },
    { "else", 6 },
    { "do", 6 },
    { "sizeof", 7 },
};

struct templ *specials = specialsinit;
int nspecials = sizeof(specialsinit) / sizeof(specialsinit[0]);
int maxspecials;

char        chartype[128] =
{               /* this is used to facilitate the decision of
                 * what type (alphanumeric, operator) each
                 * character is */
    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
};




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

    e_token = s_token;      /* point to start of place to save token */
    unary_delim = false;
    ps.col_1 = ps.last_nl;  /* tell world that this token started in
                 * column 1 iff the last thing scanned was nl */
    ps.last_nl = false;

    while (*buf_ptr == ' ' || *buf_ptr == '\t') {   /* get rid of blanks */
    ps.col_1 = false;   /* leading blanks imply token is not in column
                 * 1 */
    if (++buf_ptr >= buf_end)
        fill_buffer();
    }

    /* Scan an alphanumeric token */
    if (chartype[(int)*buf_ptr] == alphanum ||
    (buf_ptr[0] == '.' && isdigit((unsigned char)buf_ptr[1]))) {
    /*
     * we have a character or number
     */
    char *j;    /* used for searching thru list of
             * reserved words */
    if (isdigit((unsigned char)*buf_ptr) ||
        (buf_ptr[0] == '.' && isdigit((unsigned char)buf_ptr[1]))) {
        int         seendot = 0,
                    seenexp = 0,
            seensfx = 0;
        if (*buf_ptr == '0' &&
            (buf_ptr[1] == 'x' || buf_ptr[1] == 'X')) {
        *e_token++ = *buf_ptr++;
        *e_token++ = *buf_ptr++;
        while (isxdigit(*buf_ptr)) {
            CHECK_SIZE_TOKEN;
            *e_token++ = *buf_ptr++;
        }
        }
        else
        while (1) {
            if (*buf_ptr == '.') {
            if (seendot)
                break;
            else
                seendot++;
            }
            CHECK_SIZE_TOKEN;
            *e_token++ = *buf_ptr++;
            if (!isdigit((unsigned char)*buf_ptr) && *buf_ptr != '.') {
            if ((*buf_ptr != 'E' && *buf_ptr != 'e') || seenexp)
                break;
            else {
                seenexp++;
                seendot++;
                CHECK_SIZE_TOKEN;
                *e_token++ = *buf_ptr++;
                if (*buf_ptr == '+' || *buf_ptr == '-')
                *e_token++ = *buf_ptr++;
            }
            }
        }
        while (1) {
        if (!(seensfx & 1) &&
            (*buf_ptr == 'U' || *buf_ptr == 'u')) {
            CHECK_SIZE_TOKEN;
            *e_token++ = *buf_ptr++;
            seensfx |= 1;
            continue;
        }
            if (!(seensfx & 2) &&
            (*buf_ptr == 'L' || *buf_ptr == 'l')) {
            CHECK_SIZE_TOKEN;
            if (buf_ptr[1] == buf_ptr[0])
                *e_token++ = *buf_ptr++;
            *e_token++ = *buf_ptr++;
            seensfx |= 2;
            continue;
        }
        break;
        }
        if (!(seensfx & 1) &&
            (*buf_ptr == 'F' || *buf_ptr == 'f')) {
        CHECK_SIZE_TOKEN;
        *e_token++ = *buf_ptr++;
        seensfx |= 1;
        }
    }
    else
        while (chartype[(int)*buf_ptr] == alphanum) {   /* copy it over */
        CHECK_SIZE_TOKEN;
        *e_token++ = *buf_ptr++;
        if (buf_ptr >= buf_end)
            fill_buffer();
        }
    *e_token++ = '\0';
    while (*buf_ptr == ' ' || *buf_ptr == '\t') {   /* get rid of blanks */
        if (++buf_ptr >= buf_end)
        fill_buffer();
    }
    ps.its_a_keyword = false;
    ps.sizeof_keyword = false;
    if (l_struct) {     /* if last token was 'struct', then this token
                 * should be treated as a declaration */
        l_struct = false;
        last_code = ident;
        ps.last_u_d = true;
        return (decl);
    }
    ps.last_u_d = false;    /* Operator after identifier is binary */
    last_code = ident;  /* Remember that this is the code we will
                 * return */

    /*
     * This loop will check if the token is a keyword.
     */
    for (i = 0; i < nspecials; i++) {
        char *p = s_token;  /* point at scanned token */
        j = specials[i].rwd;
        if (*j++ != *p++ || *j++ != *p++)
        continue;   /* This test depends on the fact that
                 * identifiers are always at least 1 character
                 * long (ie. the first two bytes of the
                 * identifier are always meaningful) */
        if (p[-1] == 0)
        break;      /* If its a one-character identifier */
        while (*p++ == *j)
        if (*j++ == 0)
            goto found_keyword; /* I wish that C had a multi-level
                     * break... */
    }
    if (i < nspecials) {        /* we have a keyword */
    found_keyword:
        ps.its_a_keyword = true;
        ps.last_u_d = true;
        switch (specials[i].rwcode) {
        case 1:     /* it is a switch */
        return (swstmt);
        case 2:     /* a case or default */
        return (casestmt);

        case 3:     /* a "struct" */
        if (ps.p_l_follow)
            break;  /* inside parens: cast */
        l_struct = true;

        /*
         * Next time around, we will want to know that we have had a
         * 'struct'
         */
        case 4:     /* one of the declaration keywords */
        if (ps.p_l_follow) {
            ps.cast_mask |= 1 << ps.p_l_follow;
            break;  /* inside parens: cast */
        }
        last_code = decl;
        return (decl);

        case 5:     /* if, while, for */
        return (sp_paren);

        case 6:     /* do, else */
        return (sp_nparen);

        case 7:
        ps.sizeof_keyword = true;
        default:        /* all others are treated like any other
                 * identifier */
        return (ident);
        }           /* end of switch */
    }           /* end of if (found_it) */
    if (*buf_ptr == '(' && ps.tos <= 1 && ps.ind_level == 0) {
        char *tp = buf_ptr;
        while (tp < buf_end)
        if (*tp++ == ')' && (*tp == ';' || *tp == ','))
            goto not_proc;
        strncpy(ps.procname, token, sizeof ps.procname);
        // strlcpy(ps.procname, token, sizeof ps.procname);
        ps.in_parameter_declaration = 1;
        rparen_count = 1;
    not_proc:;
    }
    /*
     * The following hack attempts to guess whether or not the current
     * token is in fact a declaration keyword -- one that has been
     * typedefd
     */
    if (((*buf_ptr == '*' && buf_ptr[1] != '=') ||
        isalpha((unsigned char)*buf_ptr) || *buf_ptr == '_')
        && !ps.p_l_follow
            && !ps.block_init
        && (ps.last_token == rparen || ps.last_token == semicolon ||
            ps.last_token == decl ||
            ps.last_token == lbrace || ps.last_token == rbrace)) {
        ps.its_a_keyword = true;
        ps.last_u_d = true;
        last_code = decl;
        return decl;
    }
    if (last_code == decl)  /* if this is a declared variable, then
                 * following sign is unary */
        ps.last_u_d = true; /* will make "int a -1" work */
    last_code = ident;
    return (ident);     /* the ident is not in the list */
    }               /* end of procesing for alpanum character */

    /* Scan a non-alphanumeric token */

    *e_token++ = *buf_ptr;      /* if it is only a one-character token, it is
                 * moved here */
    *e_token = '\0';
    if (++buf_ptr >= buf_end)
    fill_buffer();

    switch (*token) {
    case '\n':
    unary_delim = ps.last_u_d;
    ps.last_nl = true;  /* remember that we just had a newline */
    code = (had_eof ? 0 : newline);

    /*
     * if data has been exausted, the newline is a dummy, and we should
     * return code to stop
     */
    break;

    case '\'':          /* start of quoted character */
    case '"':           /* start of string */
    qchar = *token;
    if (troff) {
        e_token[-1] = '`';
        if (qchar == '"')
        *e_token++ = '`';
        e_token = chfont(&bodyf, &stringf, e_token);
    }
    do {            /* copy the string */
        while (1) {     /* move one character or [/<char>]<char> */
        if (*buf_ptr == '\n') {
            printf("%d: Unterminated literal\n", line_no);
            goto stop_lit;
        }
        CHECK_SIZE_TOKEN;   /* Only have to do this once in this loop,
                     * since CHECK_SIZE guarantees that there
                     * are at least 5 entries left */
        *e_token = *buf_ptr++;
        if (buf_ptr >= buf_end)
            fill_buffer();
        if (*e_token == BACKSLASH) {    /* if escape, copy extra char */
            if (*buf_ptr == '\n')   /* check for escaped newline */
            ++line_no;
            if (troff) {
            *++e_token = BACKSLASH;
            if (*buf_ptr == BACKSLASH)
                *++e_token = BACKSLASH;
            }
            *++e_token = *buf_ptr++;
            ++e_token;  /* we must increment this again because we
                 * copied two chars */
            if (buf_ptr >= buf_end)
            fill_buffer();
        }
        else
            break;  /* we copied one character */
        }           /* end of while (1) */
    } while (*e_token++ != qchar);
    if (troff) {
        e_token = chfont(&stringf, &bodyf, e_token - 1);
        if (qchar == '"')
        *e_token++ = '\'';
    }
stop_lit:
    code = ident;
    break;

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

    case (')'):
    case (']'):
    code = rparen;
    break;

    case '#':
    unary_delim = ps.last_u_d;
    code = preesc;
    break;

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

    case (':'):
    code = colon;
    unary_delim = true;
    break;

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

    case ('{'):
    unary_delim = true;

    /*
     * if (ps.in_or_st) ps.block_init = 1;
     */
    /* ?    code = ps.block_init ? lparen : lbrace; */
    code = lbrace;
    break;

    case ('}'):
    unary_delim = true;
    /* ?    code = ps.block_init ? rparen : rbrace; */
    code = rbrace;
    break;

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

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

    case '.':
    unary_delim = false;
    code = period;
    break;

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

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

    case '=':
    if (ps.in_or_st)
        ps.block_init = 1;
#ifdef undef
    if (chartype[*buf_ptr] == opchar) { /* we have two char assignment */
        e_token[-1] = *buf_ptr++;
        if ((e_token[-1] == '<' || e_token[-1] == '>') && e_token[-1] == *buf_ptr)
        *e_token++ = *buf_ptr++;
        *e_token++ = '=';   /* Flip =+ to += */
        *e_token = 0;
    }
#else
    if (*buf_ptr == '=') {/* == */
        *e_token++ = '=';   /* Flip =+ to += */
        buf_ptr++;
        *e_token = 0;
    }
#endif
    code = binary_op;
    unary_delim = true;
    break;
    /* can drop thru!!! */

    case '>':
    case '<':
    case '!':           /* ops like <, <<, <=, !=, etc */
    if (*buf_ptr == '>' || *buf_ptr == '<' || *buf_ptr == '=') {
        *e_token++ = *buf_ptr;
        if (++buf_ptr >= buf_end)
        fill_buffer();
    }
    if (*buf_ptr == '=')
        *e_token++ = *buf_ptr++;
    code = (ps.last_u_d ? unary_op : binary_op);
    unary_delim = true;
    break;

    default:
    if (token[0] == '/' && *buf_ptr == '*') {
        /* it is start of comment */
        *e_token++ = '*';

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

        code = comment;
        unary_delim = ps.last_u_d;
        break;
    }
    while (*(e_token - 1) == *buf_ptr || *buf_ptr == '=') {
        /*
         * handle ||, &&, etc, and also things as in int *****i
         */
        *e_token++ = *buf_ptr;
        if (++buf_ptr >= buf_end)
        fill_buffer();
    }
    code = (ps.last_u_d ? unary_op : binary_op);
    unary_delim = true;


    }               /* end of switch */
    if (code != newline) {
    l_struct = false;
    last_code = code;
    }
    if (buf_ptr >= buf_end) /* check for input buffer empty */
    fill_buffer();
    ps.last_u_d = unary_delim;
    *e_token = '\0';        /* null terminate the token */
    return (code);
}

/*
 * Add the given keyword to the keyword table, using val as the keyword type
 */
void
addkey(char *key, int val)
{
    struct templ *p;
    int i;

    for (i = 0; i < nspecials; i++) {
    p = &specials[i];
    if (p->rwd[0] == key[0] && strcmp(p->rwd, key) == 0)
        return;
    }

    if (specials == specialsinit) {
    /*
     * Whoa. Must reallocate special table.
     */
    nspecials = sizeof (specialsinit) / sizeof (specialsinit[0]);
    maxspecials = nspecials + (nspecials >> 2);
    specials = calloc(maxspecials, sizeof specials[0]);
    if (specials == NULL)
        err(1, NULL);
    memcpy(specials, specialsinit, sizeof specialsinit);
    } else if (nspecials >= maxspecials) {
    int newspecials = maxspecials + (maxspecials >> 2);
    struct templ *specials2;

    specials2 = reallocarray(specials, newspecials, sizeof(specials[0]));
    if (specials2 == NULL)
        err(1, NULL);
    specials = specials2;
    maxspecials = newspecials;
    }

    p = &specials[nspecials];
    p->rwd = key;
    p->rwcode = val;
    nspecials++;
    return;
}