xref: /freebsd/usr.bin/indent/pr_comment.c (revision eb69d1f144a6fcc765d1b9d44a5ae8082353e70b)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1985 Sun Microsystems, Inc.
5  * Copyright (c) 1980, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)pr_comment.c	8.1 (Berkeley) 6/6/93";
41 #endif /* not lint */
42 #endif
43 
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 #include <err.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include "indent_globs.h"
52 #include "indent_codes.h"
53 #include "indent.h"
54 /*
55  * NAME:
56  *	pr_comment
57  *
58  * FUNCTION:
59  *	This routine takes care of scanning and printing comments.
60  *
61  * ALGORITHM:
62  *	1) Decide where the comment should be aligned, and if lines should
63  *	   be broken.
64  *	2) If lines should not be broken and filled, just copy up to end of
65  *	   comment.
66  *	3) If lines should be filled, then scan thru input_buffer copying
67  *	   characters to com_buf.  Remember where the last blank, tab, or
68  *	   newline was.  When line is filled, print up to last blank and
69  *	   continue copying.
70  *
71  * HISTORY:
72  *	November 1976	D A Willcox of CAC	Initial coding
73  *	12/6/76		D A Willcox of CAC	Modification to handle
74  *						UNIX-style comments
75  *
76  */
77 
78 /*
79  * this routine processes comments.  It makes an attempt to keep comments from
80  * going over the max line length.  If a line is too long, it moves everything
81  * from the last blank to the next comment line.  Blanks and tabs from the
82  * beginning of the input line are removed
83  */
84 
85 void
86 pr_comment(void)
87 {
88     int         now_col;	/* column we are in now */
89     int         adj_max_col;	/* Adjusted max_col for when we decide to
90 				 * spill comments over the right margin */
91     char       *last_bl;	/* points to the last blank in the output
92 				 * buffer */
93     char       *t_ptr;		/* used for moving string */
94     int         break_delim = comment_delimiter_on_blankline;
95     int         l_just_saw_decl = ps.just_saw_decl;
96     adj_max_col = max_col;
97     ps.just_saw_decl = 0;
98     last_bl = NULL;		/* no blanks found so far */
99     ps.box_com = false;		/* at first, assume that we are not in
100 					 * a boxed comment or some other
101 					 * comment that should not be touched */
102     ++ps.out_coms;		/* keep track of number of comments */
103 
104     /* Figure where to align and how to treat the comment */
105 
106     if (ps.col_1 && !format_col1_comments) {	/* if comment starts in column
107 						 * 1 it should not be touched */
108 	ps.box_com = true;
109 	break_delim = false;
110 	ps.com_col = 1;
111     }
112     else {
113 	if (*buf_ptr == '-' || *buf_ptr == '*' ||
114 	    (*buf_ptr == '\n' && !format_block_comments)) {
115 	    ps.box_com = true;	/* A comment with a '-' or '*' immediately
116 				 * after the /+* is assumed to be a boxed
117 				 * comment. A comment with a newline
118 				 * immediately after the /+* is assumed to
119 				 * be a block comment and is treated as a
120 				 * box comment unless format_block_comments
121 				 * is nonzero (the default). */
122 	    break_delim = false;
123 	}
124 	if ( /* ps.bl_line && */ (s_lab == e_lab) && (s_code == e_code)) {
125 	    /* klg: check only if this line is blank */
126 	    /*
127 	     * If this (*and previous lines are*) blank, dont put comment way
128 	     * out at left
129 	     */
130 	    ps.com_col = (ps.ind_level - ps.unindent_displace) * ps.ind_size + 1;
131 	    adj_max_col = block_comment_max_col;
132 	    if (ps.com_col <= 1)
133 		ps.com_col = 1 + !format_col1_comments;
134 	}
135 	else {
136 	    int target_col;
137 	    break_delim = false;
138 	    if (s_code != e_code)
139 		target_col = count_spaces(compute_code_target(), s_code);
140 	    else {
141 		target_col = 1;
142 		if (s_lab != e_lab)
143 		    target_col = count_spaces(compute_label_target(), s_lab);
144 	    }
145 	    ps.com_col = ps.decl_on_line || ps.ind_level == 0 ? ps.decl_com_ind : ps.com_ind;
146 	    if (ps.com_col <= target_col)
147 		ps.com_col = tabsize * (1 + (target_col - 1) / tabsize) + 1;
148 	    if (ps.com_col + 24 > adj_max_col)
149 		adj_max_col = ps.com_col + 24;
150 	}
151     }
152     if (ps.box_com) {
153 	/*
154 	 * Find out how much indentation there was originally, because that
155 	 * much will have to be ignored by pad_output() in dump_line(). This
156 	 * is a box comment, so nothing changes -- not even indentation.
157 	 *
158 	 * The comment we're about to read usually comes from in_buffer,
159 	 * unless it has been copied into save_com.
160 	 */
161 	char *start = buf_ptr >= save_com && buf_ptr < save_com + sc_size ? bp_save : buf_ptr;
162 	ps.n_comment_delta = 1 - count_spaces_until(1, in_buffer, start - 2);
163     }
164     else {
165 	ps.n_comment_delta = 0;
166 	while (*buf_ptr == ' ' || *buf_ptr == '\t')
167 	    buf_ptr++;
168     }
169     ps.comment_delta = 0;
170     *e_com++ = '/';		/* put '/' followed by '*' into buffer */
171     *e_com++ = '*';
172     if (*buf_ptr != ' ' && !ps.box_com)
173 	*e_com++ = ' ';
174 
175     /*
176      * Don't put a break delimiter if this is a one-liner that won't wrap.
177      */
178     if (break_delim)
179 	for (t_ptr = buf_ptr; *t_ptr != '\0' && *t_ptr != '\n'; t_ptr++) {
180 	    if (t_ptr >= buf_end)
181 		fill_buffer();
182 	    if (t_ptr[0] == '*' && t_ptr[1] == '/') {
183 		if (adj_max_col >= count_spaces_until(ps.com_col, buf_ptr, t_ptr + 2))
184 		    break_delim = false;
185 		break;
186 	    }
187 	}
188 
189     if (break_delim) {
190 	char       *t = e_com;
191 	e_com = s_com + 2;
192 	*e_com = 0;
193 	if (blanklines_before_blockcomments && ps.last_token != lbrace)
194 	    prefix_blankline_requested = 1;
195 	dump_line();
196 	e_com = s_com = t;
197 	if (!ps.box_com && star_comment_cont)
198 	    *e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
199     }
200 
201     if (troff)
202 	adj_max_col = 80;
203 
204     /* Start to copy the comment */
205 
206     while (1) {			/* this loop will go until the comment is
207 				 * copied */
208 	CHECK_SIZE_COM;
209 	switch (*buf_ptr) {	/* this checks for various spcl cases */
210 	case 014:		/* check for a form feed */
211 	    if (!ps.box_com) {	/* in a text comment, break the line here */
212 		ps.use_ff = true;
213 		/* fix so dump_line uses a form feed */
214 		dump_line();
215 		last_bl = NULL;
216 		if (!ps.box_com && star_comment_cont)
217 		    *e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
218 		while (*++buf_ptr == ' ' || *buf_ptr == '\t')
219 		    ;
220 	    }
221 	    else {
222 		if (++buf_ptr >= buf_end)
223 		    fill_buffer();
224 		*e_com++ = 014;
225 	    }
226 	    break;
227 
228 	case '\n':
229 	    if (had_eof) {	/* check for unexpected eof */
230 		printf("Unterminated comment\n");
231 		dump_line();
232 		return;
233 	    }
234 	    last_bl = NULL;
235 	    if (ps.box_com || ps.last_nl) {	/* if this is a boxed comment,
236 						 * we dont ignore the newline */
237 		if (s_com == e_com)
238 		    *e_com++ = ' ';
239 		if (!ps.box_com && e_com - s_com > 3) {
240 		    dump_line();
241 		    if (star_comment_cont)
242 			*e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
243 		}
244 		dump_line();
245 		if (!ps.box_com && star_comment_cont)
246 		    *e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
247 	    }
248 	    else {
249 		ps.last_nl = 1;
250 		if (*(e_com - 1) == ' ' || *(e_com - 1) == '\t')
251 		    last_bl = e_com - 1;
252 		/*
253 		 * if there was a space at the end of the last line, remember
254 		 * where it was
255 		 */
256 		else {		/* otherwise, insert one */
257 		    last_bl = e_com;
258 		    CHECK_SIZE_COM;
259 		    *e_com++ = ' ';
260 		}
261 	    }
262 	    ++line_no;		/* keep track of input line number */
263 	    if (!ps.box_com) {
264 		int         nstar = 1;
265 		do {		/* flush any blanks and/or tabs at start of
266 				 * next line */
267 		    if (++buf_ptr >= buf_end)
268 			fill_buffer();
269 		    if (*buf_ptr == '*' && --nstar >= 0) {
270 			if (++buf_ptr >= buf_end)
271 			    fill_buffer();
272 			if (*buf_ptr == '/')
273 			    goto end_of_comment;
274 		    }
275 		} while (*buf_ptr == ' ' || *buf_ptr == '\t');
276 	    }
277 	    else if (++buf_ptr >= buf_end)
278 		fill_buffer();
279 	    break;		/* end of case for newline */
280 
281 	case '*':		/* must check for possibility of being at end
282 				 * of comment */
283 	    if (++buf_ptr >= buf_end)	/* get to next char after * */
284 		fill_buffer();
285 
286 	    if (*buf_ptr == '/') {	/* it is the end!!! */
287 	end_of_comment:
288 		if (++buf_ptr >= buf_end)
289 		    fill_buffer();
290 		CHECK_SIZE_COM;
291 		if (break_delim) {
292 		    if (e_com > s_com + 3) {
293 			dump_line();
294 		    }
295 		    else
296 			s_com = e_com;
297 		    *e_com++ = ' ';
298 		}
299 		if (e_com[-1] != ' ' && e_com[-1] != '\t' && !ps.box_com)
300 		    *e_com++ = ' ';	/* ensure blank before end */
301 		*e_com++ = '*', *e_com++ = '/', *e_com = '\0';
302 		ps.just_saw_decl = l_just_saw_decl;
303 		return;
304 	    }
305 	    else		/* handle isolated '*' */
306 		*e_com++ = '*';
307 	    break;
308 	default:		/* we have a random char */
309 	    now_col = count_spaces_until(ps.com_col, s_com, e_com);
310 	    do {
311 		*e_com = *buf_ptr++;
312 		if (buf_ptr >= buf_end)
313 		    fill_buffer();
314 		if (*e_com == ' ' || *e_com == '\t')
315 		    last_bl = e_com;	/* remember we saw a blank */
316 		++e_com;
317 		now_col++;
318 	    } while (!memchr("*\n\r\b\t", *buf_ptr, 6) &&
319 		(now_col <= adj_max_col || !last_bl));
320 	    ps.last_nl = false;
321 	    if (now_col > adj_max_col && !ps.box_com && e_com[-1] > ' ') {
322 		/*
323 		 * the comment is too long, it must be broken up
324 		 */
325 		if (last_bl == NULL) {
326 		    dump_line();
327 		    if (!ps.box_com && star_comment_cont)
328 			*e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
329 		    break;
330 		}
331 		*e_com = '\0';
332 		e_com = last_bl;
333 		dump_line();
334 		if (!ps.box_com && star_comment_cont)
335 		    *e_com++ = ' ', *e_com++ = '*', *e_com++ = ' ';
336 		for (t_ptr = last_bl + 1; *t_ptr == ' ' || *t_ptr == '\t';
337 		    t_ptr++)
338 			;
339 		last_bl = NULL;
340 		while (*t_ptr != '\0') {
341 		    if (*t_ptr == ' ' || *t_ptr == '\t')
342 			last_bl = e_com;
343 		    *e_com++ = *t_ptr++;
344  		}
345 	    }
346 	    break;
347 	}
348     }
349 }
350