File: [cvs.NetBSD.org] / src / usr.bin / indent / pr_comment.c (download)
Revision 1.115, Sun Nov 7 13:38:32 2021 UTC (2 years, 5 months ago) by rillig
Branch: MAIN
Changes since 1.114: +2 -4
lines
indent: remove code that accessed out-of-bounds data from buffer
Saving and restoring the exact buffer position had been necessary before
NetBSD pr_comment.c 1.114. The code accessed the buffer data out of the
bounds of [com.s, com.e), which was rather surprising. More
specifically, it accessed com.e[-1] in a case where com.e == com.s,
relying on com.e[-1] being ' ' in most cases and '*' in the case where
the comment delimiter was written to a separate output line.
Make the code easier understandable by only ever accessing the buffer
data in the bounds [buf.s, buf.e).
No functional change.
|
/* $NetBSD: pr_comment.c,v 1.115 2021/11/07 13:38:32 rillig Exp $ */
/*-
* 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
static char sccsid[] = "@(#)pr_comment.c 8.1 (Berkeley) 6/6/93";
#endif
#include <sys/cdefs.h>
#if defined(__NetBSD__)
__RCSID("$NetBSD: pr_comment.c,v 1.115 2021/11/07 13:38:32 rillig Exp $");
#elif defined(__FreeBSD__)
__FBSDID("$FreeBSD: head/usr.bin/indent/pr_comment.c 334927 2018-06-10 16:44:18Z pstef $");
#endif
#include <assert.h>
#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include "indent.h"
static void
com_add_char(char ch)
{
if (1 >= com.l - com.e)
buf_expand(&com, 1);
*com.e++ = ch;
}
static void
com_add_delim(void)
{
if (!opt.star_comment_cont)
return;
size_t len = 3;
if (len >= (size_t)(com.l - com.e))
buf_expand(&com, len);
memcpy(com.e, " * ", len);
com.e += len;
}
static void
com_terminate(void)
{
if (1 >= com.l - com.e)
buf_expand(&com, 1);
*com.e = '\0';
}
static bool
fits_in_one_line(int max_line_length)
{
for (const char *p = inp.s; *p != '\n'; p++) {
assert(*p != '\0');
assert(inp.e - p >= 2);
if (!(p[0] == '*' && p[1] == '/'))
continue;
int len = ind_add(ps.com_ind + 3, inp.s, p);
len += ch_isblank(p[-1]) ? 2 : 3;
return len <= max_line_length;
}
return false;
}
static void
analyze_comment(bool *p_may_wrap, bool *p_break_delim,
int *p_adj_max_line_length)
{
int adj_max_line_length; /* Adjusted max_line_length for comments that
* spill over the right margin */
bool break_delim = opt.comment_delimiter_on_blankline;
int com_ind;
adj_max_line_length = opt.max_line_length;
bool may_wrap = true;
if (ps.curr_col_1 && !opt.format_col1_comments) {
may_wrap = false;
break_delim = false;
com_ind = 0;
} else {
if (*inp.s == '-' || *inp.s == '*' || token.e[-1] == '/' ||
(*inp.s == '\n' && !opt.format_block_comments)) {
may_wrap = false;
break_delim = false;
}
if (lab.s == lab.e && code.s == code.e) {
com_ind = (ps.ind_level - opt.unindent_displace) * opt.indent_size;
adj_max_line_length = opt.block_comment_max_line_length;
if (com_ind <= 0)
com_ind = opt.format_col1_comments ? 0 : 1;
} else {
break_delim = false;
int target_ind = code.s != code.e
? ind_add(compute_code_indent(), code.s, code.e)
: ind_add(compute_label_indent(), lab.s, lab.e);
com_ind = ps.decl_on_line || ps.ind_level == 0
? opt.decl_comment_column - 1 : opt.comment_column - 1;
if (com_ind <= target_ind)
com_ind = next_tab(target_ind);
if (com_ind + 25 > adj_max_line_length)
adj_max_line_length = com_ind + 25;
}
}
ps.com_ind = com_ind;
if (!may_wrap) {
/*
* Find out how much indentation there was originally, because that
* much will have to be ignored by dump_line(). This is a box comment,
* so nothing changes -- not even indentation.
*
* The comment we're about to read usually comes from inp.buf, unless
* it has been copied into save_com.
*/
const char *start;
/*
* XXX: ordered comparison between pointers from different objects
* invokes undefined behavior (C99 6.5.8).
*/
start = inp.s >= sc_buf && inp.s < sc_buf + sc_size ?
sc_buf : inp.buf;
ps.n_comment_delta = -ind_add(0, start, inp.s - 2);
} else {
ps.n_comment_delta = 0;
while (ch_isblank(*inp.s))
inp.s++;
}
ps.comment_delta = 0;
com_add_char('/');
com_add_char(token.e[-1]); /* either '*' or '/' */
if (*inp.s != ' ' && may_wrap)
com_add_char(' ');
if (break_delim && fits_in_one_line(adj_max_line_length))
break_delim = false;
if (break_delim) {
com.e = com.s + 2;
*com.e = '\0';
if (opt.blanklines_before_block_comments &&
ps.prev_token != lsym_lbrace)
blank_line_before = true;
dump_line();
com_add_delim();
}
*p_adj_max_line_length = adj_max_line_length;
*p_break_delim = break_delim;
*p_may_wrap = may_wrap;
}
/*
* Copy characters from 'inp' to 'com'. Try to keep comments from going over
* the maximum line length. To do that, remember where the last blank, tab, or
* newline was. When a line is filled, print up to the last blank and continue
* copying.
*/
static void
copy_comment_wrap(int adj_max_line_length, bool break_delim)
{
ssize_t last_blank = -1; /* index of the last blank in com.buf */
for (;;) {
switch (*inp.s) {
case '\f':
dump_line_ff();
last_blank = -1;
com_add_delim();
inp.s++;
while (ch_isblank(*inp.s))
inp.s++;
break;
case '\n':
if (had_eof) {
diag(1, "Unterminated comment");
dump_line();
return;
}
last_blank = -1;
if (ps.next_col_1) {
if (com.s == com.e)
com_add_char(' ');
if (com.e - com.s > 3) {
dump_line();
com_add_delim();
}
dump_line();
com_add_delim();
} else {
ps.next_col_1 = true;
if (!(com.e > com.s && ch_isblank(com.e[-1])))
com_add_char(' ');
last_blank = com.e - 1 - com.buf;
}
++line_no;
bool skip_asterisk = true;
do { /* flush any blanks and/or tabs at start of
* next line */
inp_skip();
if (*inp.s == '*' && skip_asterisk) {
skip_asterisk = false;
inp_skip();
if (*inp.s == '/')
goto end_of_comment;
}
} while (ch_isblank(*inp.s));
break; /* end of case for newline */
case '*':
inp_skip();
if (*inp.s == '/') {
end_of_comment:
inp_skip();
if (break_delim) {
if (com.e > com.s + 3)
dump_line();
else
com.e = com.s;
com_add_char(' ');
}
if (!(com.e > com.s && ch_isblank(com.e[-1])))
com_add_char(' ');
com_add_char('*');
com_add_char('/');
com_terminate();
return;
} else /* handle isolated '*' */
com_add_char('*');
break;
default: /* we have a random char */
;
int now_len = ind_add(ps.com_ind, com.s, com.e);
for (;;) {
char ch = inp_next();
if (ch_isblank(ch))
last_blank = com.e - com.buf;
com_add_char(ch);
now_len++;
if (memchr("*\n\r\b\t", *inp.s, 6) != NULL)
break;
if (now_len >= adj_max_line_length && last_blank != -1)
break;
}
ps.next_col_1 = false;
if (now_len <= adj_max_line_length)
break;
if (isspace((unsigned char)com.e[-1]))
break;
if (last_blank == -1) { /* only a single word in this line */
dump_line();
com_add_delim();
break;
}
const char *last_word_s = com.buf + last_blank + 1;
size_t last_word_len = (size_t)(com.e - last_word_s);
com.e = com.buf + last_blank;
dump_line();
com_add_delim();
memcpy(com.e, last_word_s, last_word_len);
com.e += last_word_len;
last_blank = -1;
}
}
}
static void
copy_comment_nowrap(void)
{
for (;;) {
if (*inp.s == '\n') {
if (token.e[-1] == '/')
goto finish;
if (had_eof) {
diag(1, "Unterminated comment");
dump_line();
return;
}
if (com.s == com.e)
com_add_char(' '); /* force output of an empty line */
dump_line();
++line_no;
inp_skip();
continue;
}
com_add_char(inp_next());
if (com.e[-2] == '*' && com.e[-1] == '/' && token.e[-1] == '*')
goto finish;
}
finish:
com_terminate();
}
/*
* Scan, reformat and output a single comment, which is either a block comment
* starting with '/' '*' or an end-of-line comment starting with '//'.
*/
void
process_comment(void)
{
int adj_max_line_length;
bool may_wrap, break_delim;
ps.just_saw_decl = 0;
ps.stats.comments++;
int saved_just_saw_decl = ps.just_saw_decl;
analyze_comment(&may_wrap, &break_delim, &adj_max_line_length);
if (may_wrap)
copy_comment_wrap(adj_max_line_length, break_delim);
else
copy_comment_nowrap();
ps.just_saw_decl = saved_just_saw_decl;
}