xref: /csrg-svn/usr.bin/indent/pr_comment.c (revision 33767)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * Copyright (c) 1976 Board of Trustees of the University of Illinois.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms are permitted
7  * provided that this notice is preserved and that due credit is given
8  * to the University of California at Berkeley and the University of
9  * Illinois at Urbana.  The name of either University may not be used
10  * to endorse or promote products derived from this software without
11  * specific prior written permission. This software is provided
12  * ``as is'' without express or implied warranty.
13  */
14 
15 #ifndef lint
16 static char sccsid[] = "@(#)pr_comment.c	5.5 (Berkeley) 03/22/88";
17 #endif /* not lint */
18 
19 /*
20  * NAME:
21  *	pr_comment
22  *
23  * FUNCTION:
24  *	This routine takes care of scanning and printing comments.
25  *
26  * ALGORITHM:
27  *	1) Decide where the comment should be aligned, and if lines should
28  *	   be broken.
29  *	2) If lines should not be broken and filled, just copy up to end of
30  *	   comment.
31  *	3) If lines should be filled, then scan thru input_buffer copying
32  *	   characters to com_buf.  Remember where the last blank, tab, or
33  *	   newline was.  When line is filled, print up to last blank and
34  *	   continue copying.
35  *
36  * HISTORY:
37  *	November 1976	D A Willcox of CAC	Initial coding
38  *	12/6/76		D A Willcox of CAC	Modification to handle
39  *						UNIX-style comments
40  *
41  */
42 
43 /*
44  * this routine processes comments.  It makes an attempt to keep comments
45  * from going over the max line length.  If a line is too long, it moves
46  * everything from the last blank to the next comment line.  Blanks and
47  * tabs from the beginning of the input line are removed
48  */
49 
50 #include "indent_globs.h"
51 
52 
53 pr_comment()
54 {
55     int         now_col;	/* column we are in now */
56     int         adj_max_col;	/* Adjusted max_col for when we decide to
57 				 * spill comments over the right margin */
58     int         col_1_com;	/* this comment should not be touched */
59     char       *last_bl;	/* points to the last blank in the output
60 				 * buffer */
61     char        achar;
62     char       *t_ptr;		/* used for moving string */
63     int         unix_comment;	/* tri-state variable used to decide if it
64 				 * is a unix-style comment. 0 means only
65 				 * blanks since /*, 1 means regular style
66 				 * comment, 2 means unix style comment */
67     int         break_delim = comment_delimiter_on_blankline;
68     int		l_just_saw_decl = ps.just_saw_decl;
69     /*
70      * int         ps.last_nl = 0;	/* true iff the last significant
71      * thing weve seen is a newline
72      */
73     int         one_liner = 1;	/* true iff this comment is a one-liner */
74     adj_max_col = max_col;
75     ps.just_saw_decl = 0;
76     last_bl = 0;		/* no blanks found so far */
77     ps.box_com = col_1_com = false;	/* at first, assume that we are
78 					 * not in a boxed comment or some
79 					 * other comment that should not
80 					 * be touched */
81     ++ps.out_coms;		/* keep track of number of comments */
82     unix_comment = 1;		/* set flag to let us figure out if there
83 				 * is a unix-style comment ** DISABLED:
84 				 * use 0 to reenable this hack! */
85 
86     /* Figure where to align and how to treat the comment */
87 
88     if (ps.col_1 && !format_col1_comments) {	/* if comment starts in
89 						 * column 1 it should not
90 						 * be touched */
91 	col_1_com = ps.box_com = true;
92 	ps.com_col = 1;
93     } else {
94 	if (*buf_ptr == '-' || *buf_ptr == '*') {
95 	    ps.box_com = true;	/* a comment with a '-' or '*' immediately
96 				 * after the /* is assumed to be a boxed
97 				 * comment */
98 	    col_1_com = true;
99 	    break_delim = 0;
100 	}
101 	if ( /* ps.bl_line && */ (s_lab == e_lab) && (s_code == e_code)) {
102 	    /* klg: check only if this line is blank */
103 	    /*
104 	     * If this (*and previous lines are*) blank, dont put comment
105 	     * way out at left
106 	     */
107 	    ps.com_col = (ps.ind_level - ps.unindent_displace) * ps.ind_size + 1;
108 	    adj_max_col = block_comment_max_col;
109 	    if (ps.com_col <= 1)
110 		ps.com_col = 1 + !format_col1_comments;
111 	} else {
112 	    register    target_col;
113 	    break_delim = 0;
114 	    if (s_code != e_code)
115 		target_col = count_spaces(compute_code_target(), s_code);
116 	    else {
117 		target_col = 1;
118 		if (s_lab != e_lab)
119 		    target_col = count_spaces(compute_label_target(), s_lab);
120 	    }
121 	    ps.com_col = ps.decl_on_line || ps.ind_level == 0 ? ps.decl_com_ind : ps.com_ind;
122 	    if (ps.com_col < target_col)
123 		ps.com_col = ((target_col + 7) & ~7) + 1;
124 	    if (ps.com_col + 24 > adj_max_col)
125 		adj_max_col = ps.com_col + 24;
126 	}
127     }
128     if (ps.box_com) {
129 	buf_ptr[-2] = 0;
130 	ps.n_comment_delta = 1 - count_spaces(1, in_buffer);
131 	ps.comment_delta = 0;
132 	buf_ptr[-2] = '/';
133     } else {
134 	ps.n_comment_delta = 0;
135 	ps.comment_delta = 0;
136 	while (*buf_ptr == ' ' || *buf_ptr == '\t')
137 	    buf_ptr++;
138     }
139     ps.comment_delta = 0;
140     *e_com++ = '/';		/* put '/*' into buffer */
141     *e_com++ = '*';
142     if (*buf_ptr != ' ' && !ps.box_com)
143 	*e_com++ = ' ';
144 
145     *e_com = '\0';
146     now_col = count_spaces(ps.com_col, s_com);	/* figure what column we
147 						 * would be in if we
148 						 * printed the comment now */
149 
150     /* Start to copy the comment */
151 
152     while (1) {			/* this loop will go until the comment is
153 				 * copied */
154 	if (*buf_ptr > 040 && *buf_ptr != '*')
155 	    ps.last_nl = 0;
156 	switch (*buf_ptr) {	/* this checks for various spcl cases */
157 	    case 014:		/* check for a form feed */
158 		if (!ps.box_com) {	/* in a text comment, break the
159 					 * line here */
160 		    ps.use_ff = true;
161 		    /* fix so dump_line uses a form feed */
162 		    dump_line();
163 		    last_bl = 0;
164 		    *e_com++ = ' ';
165 		    *e_com++ = '*';
166 		    *e_com++ = ' ';
167 		    while (*++buf_ptr == ' ' || *buf_ptr == '\t');
168 		} else {
169 		    if (++buf_ptr >= buf_end)
170 			fill_buffer();
171 		    *e_com++ = 014;
172 		}
173 		break;
174 
175 	    case '\n':
176 		if (had_eof) {	/* check for unexpected eof */
177 		    printf("Unterminated comment\n");
178 		    *e_com = '\0';
179 		    dump_line();
180 		    return;
181 		}
182 		one_liner = 0;
183 		if (ps.box_com || ps.last_nl) {	/* if this is a boxed
184 						 * comment, we dont ignore
185 						 * the newline */
186 		    if (s_com == e_com) {
187 			*e_com++ = ' ';
188 			*e_com++ = ' ';
189 		    }
190 		    *e_com = '\0';
191 		    if (!ps.box_com && e_com - s_com > 3) {
192 			if (break_delim == 1 && s_com[0] == '/'
193 			    && s_com[1] == '*' && s_com[2] == ' ') {
194 			    char       *t = e_com;
195 			    break_delim = 2;
196 			    e_com = s_com + 2;
197 			    *e_com = 0;
198 			    if (blanklines_before_blockcomments) prefix_blankline_requested = 1;
199 			    dump_line();
200 			    e_com = t;
201 			    s_com[0] = s_com[1] = s_com[2] = ' ';
202 			}
203 			dump_line();
204 			*e_com++ = ' ';
205 			*e_com++ = ' ';
206 		    }
207 		    dump_line();
208 		    now_col = ps.com_col;
209 		} else {
210 		ps.last_nl = 1;
211 		if (unix_comment != 1) {	/* we not are in
212 						 * unix_style comment */
213 		    if (unix_comment == 0 && s_code == e_code) {
214 			/*
215 			 * if it is a UNIX-style comment, ignore the
216 			 * requirement that previous line be blank for
217 			 * unindention
218 			 */
219 			ps.com_col = (ps.ind_level - ps.unindent_displace) * ps.ind_size + 1;
220 			if (ps.com_col <= 1)
221 			    ps.com_col = 2;
222 		    }
223 		    unix_comment = 2;	/* permanently remember that we
224 					 * are in this type of comment */
225 		    dump_line();
226 		    ++line_no;
227 		    now_col = ps.com_col;
228 		    *e_com++ = ' ';
229 		    /*
230 		     * fix so that the star at the start of the line will
231 		     * line up
232 		     */
233 		    do		/* flush leading white space */
234 			if (++buf_ptr >= buf_end)
235 			    fill_buffer();
236 		    while (*buf_ptr == ' ' || *buf_ptr == '\t');
237 		    break;
238 		}
239 		if (*(e_com - 1) == ' ' || *(e_com - 1) == '\t')
240 		    last_bl = e_com - 1;
241 		/*
242 		 * if there was a space at the end of the last line,
243 		 * remember where it was
244 		 */
245 		else {		/* otherwise, insert one */
246 		    last_bl = e_com;
247 		    *e_com++ = ' ';
248 		    ++now_col;
249 		}
250 		}
251 		++line_no;	/* keep track of input line number */
252 		if (!ps.box_com) {
253 		    int         nstar = 1;
254 		    do {	/* flush any blanks and/or tabs at start
255 				 * of next line */
256 			if (++buf_ptr >= buf_end)
257 			    fill_buffer();
258 			if (*buf_ptr == '*' && --nstar >= 0) {
259 			    if (++buf_ptr >= buf_end)
260 				fill_buffer();
261 			    if (*buf_ptr == '/')
262 				goto end_of_comment;
263 			}
264 		    } while (*buf_ptr == ' ' || *buf_ptr == '\t');
265 		} else if (++buf_ptr >= buf_end) fill_buffer();
266 		break;		/* end of case for newline */
267 
268 	    case '*':		/* must check for possibility of being at
269 				 * end of comment */
270 		if (++buf_ptr >= buf_end)	/* get to next char after * */
271 		    fill_buffer();
272 
273 		if (unix_comment == 0)	/* set flag to show we are not in
274 					 * unix-style comment */
275 		    unix_comment = 1;
276 
277 		if (*buf_ptr == '/') {	/* it is the end!!! */
278 	    end_of_comment:
279 		    if (++buf_ptr >= buf_end)
280 			fill_buffer();
281 
282 		    if (*(e_com - 1) != ' ' && !ps.box_com) {	/* insure blank before
283 								 * end */
284 			*e_com++ = ' ';
285 			++now_col;
286 		    }
287 		    if (break_delim == 1 && !one_liner && s_com[0] == '/'
288 			&& s_com[1] == '*' && s_com[2] == ' ') {
289 			char       *t = e_com;
290 			break_delim = 2;
291 			e_com = s_com + 2;
292 			*e_com = 0;
293 			    if (blanklines_before_blockcomments) prefix_blankline_requested = 1;
294 			dump_line();
295 			e_com = t;
296 			s_com[0] = s_com[1] = s_com[2] = ' ';
297 		    }
298 		    if (break_delim == 2 && e_com > s_com + 3
299 			 /* now_col > adj_max_col - 2 && !ps.box_com */ ) {
300 			*e_com = '\0';
301 			dump_line();
302 			now_col = ps.com_col;
303 		    }
304 		    *e_com++ = '*';
305 		    *e_com++ = '/';
306 		    *e_com = '\0';
307 		    ps.just_saw_decl = l_just_saw_decl;
308 		    return;
309 		} else {	/* handle isolated '*' */
310 		    *e_com++ = '*';
311 		    ++now_col;
312 		}
313 		break;
314 	    default:		/* we have a random char */
315 		if (unix_comment == 0 && *buf_ptr != ' ' && *buf_ptr != '\t')
316 		    unix_comment = 1;	/* we are not in unix-style
317 					 * comment */
318 
319 		*e_com = *buf_ptr++;
320 		if (buf_ptr >= buf_end)
321 		    fill_buffer();
322 
323 		if (*e_com == '\t')	/* keep track of column */
324 		    now_col = ((now_col - 1) & tabmask) + tabsize + 1;
325 		else if (*e_com == '\b')	/* this is a backspace */
326 		    --now_col;
327 		else
328 		    ++now_col;
329 
330 		if (*e_com == ' ' || *e_com == '\t')
331 		    last_bl = e_com;
332 		/* remember we saw a blank */
333 
334 		++e_com;
335 		if (now_col > adj_max_col && !ps.box_com && unix_comment == 1 && e_com[-1] > ' ') {
336 		    /* the comment is too long, it must be broken up */
337 		    if (break_delim == 1 && s_com[0] == '/'
338 			&& s_com[1] == '*' && s_com[2] == ' ') {
339 			char       *t = e_com;
340 			break_delim = 2;
341 			e_com = s_com + 2;
342 			*e_com = 0;
343 			    if (blanklines_before_blockcomments) prefix_blankline_requested = 1;
344 			dump_line();
345 			e_com = t;
346 			s_com[0] = s_com[1] = s_com[2] = ' ';
347 		    }
348 		    if (last_bl == 0) {	/* we have seen no blanks */
349 			last_bl = e_com;	/* fake it */
350 			*e_com++ = ' ';
351 		    }
352 		    *e_com = '\0';	/* print what we have */
353 		    *last_bl = '\0';
354 		    while (last_bl > s_com && last_bl[-1] < 040)
355 			*--last_bl = 0;
356 		    e_com = last_bl;
357 		    dump_line();
358 
359 		    *e_com++ = ' ';	/* add blanks for continuation */
360 		    *e_com++ = ' ';
361 		    *e_com++ = ' ';
362 
363 		    t_ptr = last_bl + 1;
364 		    last_bl = 0;
365 		    if (t_ptr >= e_com) {
366 			while (*t_ptr == ' ' || *t_ptr == '\t')
367 			    t_ptr++;
368 			while (*t_ptr != '\0') {	/* move unprinted part
369 							 * of comment down in
370 							 * buffer */
371 			    if (*t_ptr == ' ' || *t_ptr == '\t')
372 				last_bl = e_com;
373 			    *e_com++ = *t_ptr++;
374 			}
375 		    }
376 		    *e_com = '\0';
377 		    now_col = count_spaces(ps.com_col, s_com);	/* recompute current
378 								 * position */
379 		}
380 		break;
381 	}
382     }
383 }
384