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
38static	char		*man_hasc(char *);
39static	int		 man_ptext(struct roff_man *, int, char *, int);
40static	int		 man_pmacro(struct roff_man *, int, char *, int);
41
42
43int
44man_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 */
59static char *
60man_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
73void
74man_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
100static int
101man_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
176static int
177man_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
277void
278man_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