xref: /freebsd/contrib/mandoc/man.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*	$Id: man.c,v 1.187 2019/01/05 00:36:50 schwarze Exp $ */
2 /*
3  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
4  * Copyright (c) 2013-2015, 2017-2019 Ingo Schwarze <schwarze@openbsd.org>
5  * Copyright (c) 2011 Joerg Sonnenberger <joerg@netbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 #include "config.h"
20 
21 #include <sys/types.h>
22 
23 #include <assert.h>
24 #include <ctype.h>
25 #include <stdarg.h>
26 #include <stdlib.h>
27 #include <stdio.h>
28 #include <string.h>
29 
30 #include "mandoc_aux.h"
31 #include "mandoc.h"
32 #include "roff.h"
33 #include "man.h"
34 #include "libmandoc.h"
35 #include "roff_int.h"
36 #include "libman.h"
37 
38 static	char		*man_hasc(char *);
39 static	int		 man_ptext(struct roff_man *, int, char *, int);
40 static	int		 man_pmacro(struct roff_man *, int, char *, int);
41 
42 
43 int
44 man_parseln(struct roff_man *man, int ln, char *buf, int offs)
45 {
46 
47 	if (man->last->type != ROFFT_EQN || ln > man->last->line)
48 		man->flags |= MAN_NEWLINE;
49 
50 	return roff_getcontrol(man->roff, buf, &offs) ?
51 	    man_pmacro(man, ln, buf, offs) :
52 	    man_ptext(man, ln, buf, offs);
53 }
54 
55 /*
56  * If the string ends with \c, return a pointer to the backslash.
57  * Otherwise, return NULL.
58  */
59 static char *
60 man_hasc(char *start)
61 {
62 	char	*cp, *ep;
63 
64 	ep = strchr(start, '\0') - 2;
65 	if (ep < start || ep[0] != '\\' || ep[1] != 'c')
66 		return NULL;
67 	for (cp = ep; cp > start; cp--)
68 		if (cp[-1] != '\\')
69 			break;
70 	return (ep - cp) % 2 ? NULL : ep;
71 }
72 
73 void
74 man_descope(struct roff_man *man, int line, int offs, char *start)
75 {
76 	/* Trailing \c keeps next-line scope open. */
77 
78 	if (start != NULL && man_hasc(start) != NULL)
79 		return;
80 
81 	/*
82 	 * Co-ordinate what happens with having a next-line scope open:
83 	 * first close out the element scopes (if applicable),
84 	 * then close out the block scope (also if applicable).
85 	 */
86 
87 	if (man->flags & MAN_ELINE) {
88 		while (man->last->parent->type != ROFFT_ROOT &&
89 		    man_macro(man->last->parent->tok)->flags & MAN_ESCOPED)
90 			man_unscope(man, man->last->parent);
91 		man->flags &= ~MAN_ELINE;
92 	}
93 	if ( ! (man->flags & MAN_BLINE))
94 		return;
95 	man_unscope(man, man->last->parent);
96 	roff_body_alloc(man, line, offs, man->last->tok);
97 	man->flags &= ~(MAN_BLINE | ROFF_NONOFILL);
98 }
99 
100 static int
101 man_ptext(struct roff_man *man, int line, char *buf, int offs)
102 {
103 	int		 i;
104 	char		*ep;
105 
106 	/* In no-fill mode, whitespace is preserved on text lines. */
107 
108 	if (man->flags & ROFF_NOFILL) {
109 		roff_word_alloc(man, line, offs, buf + offs);
110 		man_descope(man, line, offs, buf + offs);
111 		return 1;
112 	}
113 
114 	for (i = offs; buf[i] == ' '; i++)
115 		/* Skip leading whitespace. */ ;
116 
117 	/*
118 	 * Blank lines are ignored in next line scope
119 	 * and right after headings and cancel preceding \c,
120 	 * but add a single vertical space elsewhere.
121 	 */
122 
123 	if (buf[i] == '\0') {
124 		if (man->flags & (MAN_ELINE | MAN_BLINE)) {
125 			mandoc_msg(MANDOCERR_BLK_BLANK, line, 0, NULL);
126 			return 1;
127 		}
128 		if (man->last->tok == MAN_SH || man->last->tok == MAN_SS)
129 			return 1;
130 		if (man->last->type == ROFFT_TEXT &&
131 		    ((ep = man_hasc(man->last->string)) != NULL)) {
132 			*ep = '\0';
133 			return 1;
134 		}
135 		roff_elem_alloc(man, line, offs, ROFF_sp);
136 		man->next = ROFF_NEXT_SIBLING;
137 		return 1;
138 	}
139 
140 	/*
141 	 * Warn if the last un-escaped character is whitespace. Then
142 	 * strip away the remaining spaces (tabs stay!).
143 	 */
144 
145 	i = (int)strlen(buf);
146 	assert(i);
147 
148 	if (' ' == buf[i - 1] || '\t' == buf[i - 1]) {
149 		if (i > 1 && '\\' != buf[i - 2])
150 			mandoc_msg(MANDOCERR_SPACE_EOL, line, i - 1, NULL);
151 
152 		for (--i; i && ' ' == buf[i]; i--)
153 			/* Spin back to non-space. */ ;
154 
155 		/* Jump ahead of escaped whitespace. */
156 		i += '\\' == buf[i] ? 2 : 1;
157 
158 		buf[i] = '\0';
159 	}
160 	roff_word_alloc(man, line, offs, buf + offs);
161 
162 	/*
163 	 * End-of-sentence check.  If the last character is an unescaped
164 	 * EOS character, then flag the node as being the end of a
165 	 * sentence.  The front-end will know how to interpret this.
166 	 */
167 
168 	assert(i);
169 	if (mandoc_eos(buf, (size_t)i))
170 		man->last->flags |= NODE_EOS;
171 
172 	man_descope(man, line, offs, buf + offs);
173 	return 1;
174 }
175 
176 static int
177 man_pmacro(struct roff_man *man, int ln, char *buf, int offs)
178 {
179 	struct roff_node *n;
180 	const char	*cp;
181 	size_t		 sz;
182 	enum roff_tok	 tok;
183 	int		 ppos;
184 	int		 bline;
185 
186 	/* Determine the line macro. */
187 
188 	ppos = offs;
189 	tok = TOKEN_NONE;
190 	for (sz = 0; sz < 4 && strchr(" \t\\", buf[offs]) == NULL; sz++)
191 		offs++;
192 	if (sz > 0 && sz < 4)
193 		tok = roffhash_find(man->manmac, buf + ppos, sz);
194 	if (tok == TOKEN_NONE) {
195 		mandoc_msg(MANDOCERR_MACRO, ln, ppos, "%s", buf + ppos - 1);
196 		return 1;
197 	}
198 
199 	/* Skip a leading escape sequence or tab. */
200 
201 	switch (buf[offs]) {
202 	case '\\':
203 		cp = buf + offs + 1;
204 		mandoc_escape(&cp, NULL, NULL);
205 		offs = cp - buf;
206 		break;
207 	case '\t':
208 		offs++;
209 		break;
210 	default:
211 		break;
212 	}
213 
214 	/* Jump to the next non-whitespace word. */
215 
216 	while (buf[offs] == ' ')
217 		offs++;
218 
219 	/*
220 	 * Trailing whitespace.  Note that tabs are allowed to be passed
221 	 * into the parser as "text", so we only warn about spaces here.
222 	 */
223 
224 	if (buf[offs] == '\0' && buf[offs - 1] == ' ')
225 		mandoc_msg(MANDOCERR_SPACE_EOL, ln, offs - 1, NULL);
226 
227 	/*
228 	 * Some macros break next-line scopes; otherwise, remember
229 	 * whether we are in next-line scope for a block head.
230 	 */
231 
232 	man_breakscope(man, tok);
233 	bline = man->flags & MAN_BLINE;
234 
235 	/*
236 	 * If the line in next-line scope ends with \c, keep the
237 	 * next-line scope open for the subsequent input line.
238 	 * That is not at all portable, only groff >= 1.22.4
239 	 * does it, but *if* this weird idiom occurs in a manual
240 	 * page, that's very likely what the author intended.
241 	 */
242 
243 	if (bline && man_hasc(buf + offs))
244 		bline = 0;
245 
246 	/* Call to handler... */
247 
248 	(*man_macro(tok)->fp)(man, tok, ln, ppos, &offs, buf);
249 
250 	/* In quick mode (for mandocdb), abort after the NAME section. */
251 
252 	if (man->quick && tok == MAN_SH) {
253 		n = man->last;
254 		if (n->type == ROFFT_BODY &&
255 		    strcmp(n->prev->child->string, "NAME"))
256 			return 2;
257 	}
258 
259 	/*
260 	 * If we are in a next-line scope for a block head,
261 	 * close it out now and switch to the body,
262 	 * unless the next-line scope is allowed to continue.
263 	 */
264 
265 	if (bline == 0 ||
266 	    (man->flags & MAN_BLINE) == 0 ||
267 	    man->flags & MAN_ELINE ||
268 	    man_macro(tok)->flags & MAN_NSCOPED)
269 		return 1;
270 
271 	man_unscope(man, man->last->parent);
272 	roff_body_alloc(man, ln, ppos, man->last->tok);
273 	man->flags &= ~(MAN_BLINE | ROFF_NONOFILL);
274 	return 1;
275 }
276 
277 void
278 man_breakscope(struct roff_man *man, int tok)
279 {
280 	struct roff_node *n;
281 
282 	/*
283 	 * An element next line scope is open,
284 	 * and the new macro is not allowed inside elements.
285 	 * Delete the element that is being broken.
286 	 */
287 
288 	if (man->flags & MAN_ELINE && (tok < MAN_TH ||
289 	    (man_macro(tok)->flags & MAN_NSCOPED) == 0)) {
290 		n = man->last;
291 		if (n->type == ROFFT_TEXT)
292 			n = n->parent;
293 		if (n->tok < MAN_TH ||
294 		    (man_macro(n->tok)->flags & (MAN_NSCOPED | MAN_ESCOPED))
295 		     == MAN_NSCOPED)
296 			n = n->parent;
297 
298 		mandoc_msg(MANDOCERR_BLK_LINE, n->line, n->pos,
299 		    "%s breaks %s", roff_name[tok], roff_name[n->tok]);
300 
301 		roff_node_delete(man, n);
302 		man->flags &= ~MAN_ELINE;
303 	}
304 
305 	/*
306 	 * Weird special case:
307 	 * Switching fill mode closes section headers.
308 	 */
309 
310 	if (man->flags & MAN_BLINE &&
311 	    (tok == ROFF_nf || tok == ROFF_fi) &&
312 	    (man->last->tok == MAN_SH || man->last->tok == MAN_SS)) {
313 		n = man->last;
314 		man_unscope(man, n);
315 		roff_body_alloc(man, n->line, n->pos, n->tok);
316 		man->flags &= ~(MAN_BLINE | ROFF_NONOFILL);
317 	}
318 
319 	/*
320 	 * A block header next line scope is open,
321 	 * and the new macro is not allowed inside block headers.
322 	 * Delete the block that is being broken.
323 	 */
324 
325 	if (man->flags & MAN_BLINE && tok != ROFF_nf && tok != ROFF_fi &&
326 	    (tok < MAN_TH || man_macro(tok)->flags & MAN_XSCOPE)) {
327 		n = man->last;
328 		if (n->type == ROFFT_TEXT)
329 			n = n->parent;
330 		if (n->tok < MAN_TH ||
331 		    (man_macro(n->tok)->flags & MAN_XSCOPE) == 0)
332 			n = n->parent;
333 
334 		assert(n->type == ROFFT_HEAD);
335 		n = n->parent;
336 		assert(n->type == ROFFT_BLOCK);
337 		assert(man_macro(n->tok)->flags & MAN_BSCOPED);
338 
339 		mandoc_msg(MANDOCERR_BLK_LINE, n->line, n->pos,
340 		    "%s breaks %s", roff_name[tok], roff_name[n->tok]);
341 
342 		roff_node_delete(man, n);
343 		man->flags &= ~(MAN_BLINE | ROFF_NONOFILL);
344 	}
345 }
346