freebsd-nq/usr.bin/indent/lexi.c
Piotr Pawel Stefaniak 01c66110e1 indent(1): rewrite the integer/floating constant scanning part of lexi.c
Remove procedural code that did the scanning, which was faulty and didn't
support complex constants such as 0x1p-61. Replace it with a finite state
machine expressed as a transition table. The table was rewritten by hand
from lx's output, given parts of grammar expressed as regular expressions.

lx is Katherine Flavel's lexer generator, currently available at
https://github.com/katef/libfsm and the parts of grammar were taken from
http://quut.com/c/ANSI-C-grammar-l-2011.html and extended to support binary
integer constants which are a popular GCC extension.

Reported by:	bde
2018-07-16 05:46:50 +00:00

653 lines
17 KiB
C

/*-
* SPDX-License-Identifier: BSD-4-Clause
*
* Copyright (c) 1985 Sun Microsystems, Inc.
* Copyright (c) 1980, 1993
* The Regents of the University of California. All rights reserved.
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#if 0
#ifndef lint
static char sccsid[] = "@(#)lexi.c 8.1 (Berkeley) 6/6/93";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* 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 <err.h>
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#include "indent_globs.h"
#include "indent_codes.h"
#include "indent.h"
struct templ {
const char *rwd;
int rwcode;
};
/*
* This table has to be sorted alphabetically, because it'll be used in binary
* search. For the same reason, string must be the first thing in struct templ.
*/
struct templ specials[] =
{
{"_Bool", 4},
{"_Complex", 4},
{"_Imaginary", 4},
{"auto", 10},
{"bool", 4},
{"break", 9},
{"case", 8},
{"char", 4},
{"complex", 4},
{"const", 4},
{"continue", 12},
{"default", 8},
{"do", 6},
{"double", 4},
{"else", 6},
{"enum", 3},
{"extern", 10},
{"float", 4},
{"for", 5},
{"global", 4},
{"goto", 9},
{"if", 5},
{"imaginary", 4},
{"inline", 12},
{"int", 4},
{"long", 4},
{"offsetof", 1},
{"register", 10},
{"restrict", 12},
{"return", 9},
{"short", 4},
{"signed", 4},
{"sizeof", 2},
{"static", 10},
{"struct", 3},
{"switch", 7},
{"typedef", 11},
{"union", 3},
{"unsigned", 4},
{"void", 4},
{"volatile", 4},
{"while", 5}
};
const char **typenames;
int typename_count;
int typename_top = -1;
/*
* The transition table below was rewritten by hand from lx's output, given
* the following definitions. lx is Katherine Flavel's lexer generator.
*
* O = /[0-7]/; D = /[0-9]/; NZ = /[1-9]/;
* H = /[a-f0-9]/i; B = /[0-1]/; HP = /0x/i;
* BP = /0b/i; E = /e[+\-]?/i D+; P = /p[+\-]?/i D+;
* FS = /[fl]/i; IS = /u/i /(l|L|ll|LL)/? | /(l|L|ll|LL)/ /u/i?;
*
* D+ E FS? -> $float;
* D* "." D+ E? FS? -> $float;
* D+ "." E? FS? -> $float; HP H+ IS? -> $int;
* HP H+ P FS? -> $float; NZ D* IS? -> $int;
* HP H* "." H+ P FS? -> $float; "0" O* IS? -> $int;
* HP H+ "." P FS -> $float; BP B+ IS? -> $int;
*/
static char const *table[] = {
/* examples:
00
s 0xx
t 00xaa
a 11 101100xxa..
r 11ee0001101lbuuxx.a.pp
t.01.e+008bLuxll0Ll.aa.p+0
states: ABCDEFGHIJKLMNOPQRSTUVWXYZ */
['0'] = "CEIDEHHHIJQ U Q VUVVZZZ",
['1'] = "DEIDEHHHIJQ U Q VUVVZZZ",
['7'] = "DEIDEHHHIJ U VUVVZZZ",
['9'] = "DEJDEHHHJJ U VUVVZZZ",
['a'] = " U VUVV ",
['b'] = " K U VUVV ",
['e'] = " FFF FF U VUVV ",
['f'] = " f f U VUVV f",
['u'] = " MM M i iiM M ",
['x'] = " N ",
['p'] = " FFX ",
['L'] = " LLf fL PR Li L f",
['l'] = " OOf fO S P O i O f",
['+'] = " G Y ",
['.'] = "B EE EE T W ",
/* ABCDEFGHIJKLMNOPQRSTUVWXYZ */
[0] = "uuiifuufiuuiiuiiiiiuiuuuuu",
};
static int
strcmp_type(const void *e1, const void *e2)
{
return (strcmp(e1, *(const char * const *)e2));
}
int
lexi(struct parser_state *state)
{
int unary_delim; /* this is set to 1 if the current token
* forces a following operator to be unary */
int code; /* internal code to be returned */
char qchar; /* the delimiter character for a string */
e_token = s_token; /* point to start of place to save token */
unary_delim = false;
state->col_1 = state->last_nl; /* tell world that this token started
* in column 1 iff the last thing
* scanned was a newline */
state->last_nl = false;
while (*buf_ptr == ' ' || *buf_ptr == '\t') { /* get rid of blanks */
state->col_1 = false; /* leading blanks imply token is not in column
* 1 */
if (++buf_ptr >= buf_end)
fill_buffer();
}
/* Scan an alphanumeric token */
if (isalnum((unsigned char)*buf_ptr) ||
(buf_ptr[0] == '.' && isdigit((unsigned char)buf_ptr[1]))) {
/*
* we have a character or number
*/
struct templ *p;
if (isdigit((unsigned char)*buf_ptr) ||
(buf_ptr[0] == '.' && isdigit((unsigned char)buf_ptr[1]))) {
char s;
unsigned char i;
for (s = 'A'; s != 'f' && s != 'i' && s != 'u'; ) {
i = (unsigned char)*buf_ptr;
if (i >= nitems(table) || table[i] == NULL ||
table[i][s - 'A'] == ' ') {
s = table[0][s - 'A'];
break;
}
s = table[i][s - 'A'];
CHECK_SIZE_TOKEN(1);
*e_token++ = *buf_ptr++;
if (buf_ptr >= buf_end)
fill_buffer();
}
/* s now indicates the type: f(loating), i(integer), u(nknown) */
}
else
while (isalnum((unsigned char)*buf_ptr) ||
*buf_ptr == BACKSLASH ||
*buf_ptr == '_') {
/* fill_buffer() terminates buffer with newline */
if (*buf_ptr == BACKSLASH) {
if (*(buf_ptr + 1) == '\n') {
buf_ptr += 2;
if (buf_ptr >= buf_end)
fill_buffer();
} else
break;
}
CHECK_SIZE_TOKEN(1);
/* copy it over */
*e_token++ = *buf_ptr++;
if (buf_ptr >= buf_end)
fill_buffer();
}
*e_token = '\0';
if (s_token[0] == 'L' && s_token[1] == '\0' &&
(*buf_ptr == '"' || *buf_ptr == '\''))
return (strpfx);
while (*buf_ptr == ' ' || *buf_ptr == '\t') { /* get rid of blanks */
if (++buf_ptr >= buf_end)
fill_buffer();
}
state->keyword = 0;
if (state->last_token == structure && !state->p_l_follow) {
/* if last token was 'struct' and we're not
* in parentheses, then this token
* should be treated as a declaration */
state->last_u_d = true;
return (decl);
}
/*
* Operator after identifier is binary unless last token was 'struct'
*/
state->last_u_d = (state->last_token == structure);
p = bsearch(s_token,
specials,
sizeof(specials) / sizeof(specials[0]),
sizeof(specials[0]),
strcmp_type);
if (p == NULL) { /* not a special keyword... */
char *u;
/* ... so maybe a type_t or a typedef */
if ((opt.auto_typedefs && ((u = strrchr(s_token, '_')) != NULL) &&
strcmp(u, "_t") == 0) || (typename_top >= 0 &&
bsearch(s_token, typenames, typename_top + 1,
sizeof(typenames[0]), strcmp_type))) {
state->keyword = 4; /* a type name */
state->last_u_d = true;
goto found_typename;
}
} else { /* we have a keyword */
state->keyword = p->rwcode;
state->last_u_d = true;
switch (p->rwcode) {
case 7: /* it is a switch */
return (swstmt);
case 8: /* a case or default */
return (casestmt);
case 3: /* a "struct" */
/* FALLTHROUGH */
case 4: /* one of the declaration keywords */
found_typename:
if (state->p_l_follow) {
/* inside parens: cast, param list, offsetof or sizeof */
state->cast_mask |= (1 << state->p_l_follow) & ~state->not_cast_mask;
}
if (state->last_token == period || state->last_token == unary_op) {
state->keyword = 0;
break;
}
if (p != NULL && p->rwcode == 3)
return (structure);
if (state->p_l_follow)
break;
return (decl);
case 5: /* if, while, for */
return (sp_paren);
case 6: /* do, else */
return (sp_nparen);
case 10: /* storage class specifier */
return (storage);
case 11: /* typedef */
return (type_def);
default: /* all others are treated like any other
* identifier */
return (ident);
} /* end of switch */
} /* end of if (found_it) */
if (*buf_ptr == '(' && state->tos <= 1 && state->ind_level == 0 &&
state->in_parameter_declaration == 0 && state->block_init == 0) {
char *tp = buf_ptr;
while (tp < buf_end)
if (*tp++ == ')' && (*tp == ';' || *tp == ','))
goto not_proc;
strncpy(state->procname, token, sizeof state->procname - 1);
if (state->in_decl)
state->in_parameter_declaration = 1;
return (funcname);
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
*/
else if (!state->p_l_follow && !state->block_init &&
!state->in_stmt &&
((*buf_ptr == '*' && buf_ptr[1] != '=') ||
isalpha((unsigned char)*buf_ptr)) &&
(state->last_token == semicolon || state->last_token == lbrace ||
state->last_token == rbrace)) {
state->keyword = 4; /* a type name */
state->last_u_d = true;
return decl;
}
if (state->last_token == decl) /* if this is a declared variable,
* then following sign is unary */
state->last_u_d = true; /* will make "int a -1" work */
return (ident); /* the ident is not in the list */
} /* end of procesing for alpanum character */
/* Scan a non-alphanumeric token */
CHECK_SIZE_TOKEN(3); /* things like "<<=" */
*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 = state->last_u_d;
state->last_nl = true; /* remember that we just had a newline */
code = (had_eof ? 0 : newline);
/*
* if data has been exhausted, the newline is a dummy, and we should
* return code to stop
*/
break;
case '\'': /* start of quoted character */
case '"': /* start of string */
qchar = *token;
do { /* copy the string */
while (1) { /* move one character or [/<char>]<char> */
if (*buf_ptr == '\n') {
diag2(1, "Unterminated literal");
goto stop_lit;
}
CHECK_SIZE_TOKEN(2);
*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;
*++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);
stop_lit:
code = ident;
break;
case ('('):
case ('['):
unary_delim = true;
code = lparen;
break;
case (')'):
case (']'):
code = rparen;
break;
case '#':
unary_delim = state->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 (state->in_or_st) state->block_init = 1;
*/
/* ? code = state->block_init ? lparen : lbrace; */
code = lbrace;
break;
case ('}'):
unary_delim = true;
/* ? code = state->block_init ? rparen : rbrace; */
code = rbrace;
break;
case 014: /* a form feed */
unary_delim = state->last_u_d;
state->last_nl = true; /* remember this so we can set 'state->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 = (state->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 (state->last_token == ident || state->last_token == rparen) {
code = (state->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++;
unary_delim = false;
code = unary_op;
state->want_blank = false;
}
break; /* buffer overflow will be checked at end of
* switch */
case '=':
if (state->in_or_st)
state->block_init = 1;
if (*buf_ptr == '=') {/* == */
*e_token++ = '='; /* Flip =+ to += */
buf_ptr++;
*e_token = 0;
}
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 = (state->last_u_d ? unary_op : binary_op);
unary_delim = true;
break;
case '*':
unary_delim = true;
if (!state->last_u_d) {
if (*buf_ptr == '=')
*e_token++ = *buf_ptr++;
code = binary_op;
break;
}
while (*buf_ptr == '*' || isspace((unsigned char)*buf_ptr)) {
if (*buf_ptr == '*') {
CHECK_SIZE_TOKEN(1);
*e_token++ = *buf_ptr;
}
if (++buf_ptr >= buf_end)
fill_buffer();
}
if (ps.in_decl) {
char *tp = buf_ptr;
while (isalpha((unsigned char)*tp) ||
isspace((unsigned char)*tp)) {
if (++tp >= buf_end)
fill_buffer();
}
if (*tp == '(')
ps.procname[0] = ' ';
}
code = unary_op;
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 = state->last_u_d;
break;
}
while (*(e_token - 1) == *buf_ptr || *buf_ptr == '=') {
/*
* handle ||, &&, etc, and also things as in int *****i
*/
CHECK_SIZE_TOKEN(1);
*e_token++ = *buf_ptr;
if (++buf_ptr >= buf_end)
fill_buffer();
}
code = (state->last_u_d ? unary_op : binary_op);
unary_delim = true;
} /* end of switch */
if (buf_ptr >= buf_end) /* check for input buffer empty */
fill_buffer();
state->last_u_d = unary_delim;
CHECK_SIZE_TOKEN(1);
*e_token = '\0'; /* null terminate the token */
return (code);
}
/* Initialize constant transition table */
void
init_constant_tt(void)
{
table['-'] = table['+'];
table['8'] = table['9'];
table['2'] = table['3'] = table['4'] = table['5'] = table['6'] = table['7'];
table['A'] = table['C'] = table['D'] = table['c'] = table['d'] = table['a'];
table['B'] = table['b'];
table['E'] = table['e'];
table['U'] = table['u'];
table['X'] = table['x'];
table['P'] = table['p'];
table['F'] = table['f'];
}
void
alloc_typenames(void)
{
typenames = (const char **)malloc(sizeof(typenames[0]) *
(typename_count = 16));
if (typenames == NULL)
err(1, NULL);
}
void
add_typename(const char *key)
{
int comparison;
const char *copy;
if (typename_top + 1 >= typename_count) {
typenames = realloc((void *)typenames,
sizeof(typenames[0]) * (typename_count *= 2));
if (typenames == NULL)
err(1, NULL);
}
if (typename_top == -1)
typenames[++typename_top] = copy = strdup(key);
else if ((comparison = strcmp(key, typenames[typename_top])) >= 0) {
/* take advantage of sorted input */
if (comparison == 0) /* remove duplicates */
return;
typenames[++typename_top] = copy = strdup(key);
}
else {
int p;
for (p = 0; (comparison = strcmp(key, typenames[p])) > 0; p++)
/* find place for the new key */;
if (comparison == 0) /* remove duplicates */
return;
memmove(&typenames[p + 1], &typenames[p],
sizeof(typenames[0]) * (++typename_top - p));
typenames[p] = copy = strdup(key);
}
if (copy == NULL)
err(1, NULL);
}