xref: /dragonfly/contrib/mdocml/mdoc_macro.c (revision ce7a3582)
1 /*	$Id: mdoc_macro.c,v 1.109 2011/04/30 10:18:24 kristaps Exp $ */
2 /*
3  * Copyright (c) 2008, 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
4  * Copyright (c) 2010 Ingo Schwarze <schwarze@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 #ifdef HAVE_CONFIG_H
19 #include "config.h"
20 #endif
21 
22 #include <assert.h>
23 #include <ctype.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <time.h>
28 
29 #include "mdoc.h"
30 #include "mandoc.h"
31 #include "libmdoc.h"
32 #include "libmandoc.h"
33 
34 enum	rew {	/* see rew_dohalt() */
35 	REWIND_NONE,
36 	REWIND_THIS,
37 	REWIND_MORE,
38 	REWIND_FORCE,
39 	REWIND_LATER,
40 	REWIND_ERROR
41 };
42 
43 static	int	  	blk_full(MACRO_PROT_ARGS);
44 static	int	  	blk_exp_close(MACRO_PROT_ARGS);
45 static	int	  	blk_part_exp(MACRO_PROT_ARGS);
46 static	int	  	blk_part_imp(MACRO_PROT_ARGS);
47 static	int	  	ctx_synopsis(MACRO_PROT_ARGS);
48 static	int	  	in_line_eoln(MACRO_PROT_ARGS);
49 static	int	  	in_line_argn(MACRO_PROT_ARGS);
50 static	int	  	in_line(MACRO_PROT_ARGS);
51 static	int	  	obsolete(MACRO_PROT_ARGS);
52 static	int	  	phrase_ta(MACRO_PROT_ARGS);
53 
54 static	int		dword(struct mdoc *, int, int,
55 				const char *, enum mdelim);
56 static	int	  	append_delims(struct mdoc *,
57 				int, int *, char *);
58 static	enum mdoct	lookup(enum mdoct, const char *);
59 static	enum mdoct	lookup_raw(const char *);
60 static	int		make_pending(struct mdoc_node *, enum mdoct,
61 				struct mdoc *, int, int);
62 static	int	  	phrase(struct mdoc *, int, int, char *);
63 static	enum mdoct 	rew_alt(enum mdoct);
64 static	enum rew  	rew_dohalt(enum mdoct, enum mdoc_type,
65 				const struct mdoc_node *);
66 static	int	  	rew_elem(struct mdoc *, enum mdoct);
67 static	int	  	rew_last(struct mdoc *,
68 				const struct mdoc_node *);
69 static	int	  	rew_sub(enum mdoc_type, struct mdoc *,
70 				enum mdoct, int, int);
71 
72 const	struct mdoc_macro __mdoc_macros[MDOC_MAX] = {
73 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Ap */
74 	{ in_line_eoln, MDOC_PROLOGUE }, /* Dd */
75 	{ in_line_eoln, MDOC_PROLOGUE }, /* Dt */
76 	{ in_line_eoln, MDOC_PROLOGUE }, /* Os */
77 	{ blk_full, 0 }, /* Sh */
78 	{ blk_full, 0 }, /* Ss */
79 	{ in_line_eoln, 0 }, /* Pp */
80 	{ blk_part_imp, MDOC_PARSED }, /* D1 */
81 	{ blk_part_imp, MDOC_PARSED }, /* Dl */
82 	{ blk_full, MDOC_EXPLICIT }, /* Bd */
83 	{ blk_exp_close, MDOC_EXPLICIT }, /* Ed */
84 	{ blk_full, MDOC_EXPLICIT }, /* Bl */
85 	{ blk_exp_close, MDOC_EXPLICIT }, /* El */
86 	{ blk_full, MDOC_PARSED }, /* It */
87 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ad */
88 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* An */
89 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ar */
90 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Cd */
91 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Cm */
92 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Dv */
93 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Er */
94 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ev */
95 	{ in_line_eoln, 0 }, /* Ex */
96 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Fa */
97 	{ in_line_eoln, 0 }, /* Fd */
98 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Fl */
99 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Fn */
100 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ft */
101 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ic */
102 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* In */
103 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Li */
104 	{ blk_full, 0 }, /* Nd */
105 	{ ctx_synopsis, MDOC_CALLABLE | MDOC_PARSED }, /* Nm */
106 	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Op */
107 	{ obsolete, 0 }, /* Ot */
108 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Pa */
109 	{ in_line_eoln, 0 }, /* Rv */
110 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* St */
111 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Va */
112 	{ ctx_synopsis, MDOC_CALLABLE | MDOC_PARSED }, /* Vt */
113 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Xr */
114 	{ in_line_eoln, 0 }, /* %A */
115 	{ in_line_eoln, 0 }, /* %B */
116 	{ in_line_eoln, 0 }, /* %D */
117 	{ in_line_eoln, 0 }, /* %I */
118 	{ in_line_eoln, 0 }, /* %J */
119 	{ in_line_eoln, 0 }, /* %N */
120 	{ in_line_eoln, 0 }, /* %O */
121 	{ in_line_eoln, 0 }, /* %P */
122 	{ in_line_eoln, 0 }, /* %R */
123 	{ in_line_eoln, 0 }, /* %T */
124 	{ in_line_eoln, 0 }, /* %V */
125 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Ac */
126 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Ao */
127 	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Aq */
128 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* At */
129 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Bc */
130 	{ blk_full, MDOC_EXPLICIT }, /* Bf */
131 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Bo */
132 	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Bq */
133 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Bsx */
134 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Bx */
135 	{ in_line_eoln, 0 }, /* Db */
136 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Dc */
137 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Do */
138 	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Dq */
139 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Ec */
140 	{ blk_exp_close, MDOC_EXPLICIT }, /* Ef */
141 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Em */
142 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Eo */
143 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Fx */
144 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ms */
145 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED | MDOC_IGNDELIM }, /* No */
146 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED | MDOC_IGNDELIM }, /* Ns */
147 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Nx */
148 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Ox */
149 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Pc */
150 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED | MDOC_IGNDELIM }, /* Pf */
151 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Po */
152 	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Pq */
153 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Qc */
154 	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Ql */
155 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Qo */
156 	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Qq */
157 	{ blk_exp_close, MDOC_EXPLICIT }, /* Re */
158 	{ blk_full, MDOC_EXPLICIT }, /* Rs */
159 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Sc */
160 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* So */
161 	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Sq */
162 	{ in_line_eoln, 0 }, /* Sm */
163 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Sx */
164 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Sy */
165 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Tn */
166 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Ux */
167 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Xc */
168 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Xo */
169 	{ blk_full, MDOC_EXPLICIT | MDOC_CALLABLE }, /* Fo */
170 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Fc */
171 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Oo */
172 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Oc */
173 	{ blk_full, MDOC_EXPLICIT }, /* Bk */
174 	{ blk_exp_close, MDOC_EXPLICIT }, /* Ek */
175 	{ in_line_eoln, 0 }, /* Bt */
176 	{ in_line_eoln, 0 }, /* Hf */
177 	{ obsolete, 0 }, /* Fr */
178 	{ in_line_eoln, 0 }, /* Ud */
179 	{ in_line, 0 }, /* Lb */
180 	{ in_line_eoln, 0 }, /* Lp */
181 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Lk */
182 	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Mt */
183 	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Brq */
184 	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Bro */
185 	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Brc */
186 	{ in_line_eoln, 0 }, /* %C */
187 	{ obsolete, 0 }, /* Es */
188 	{ obsolete, 0 }, /* En */
189 	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Dx */
190 	{ in_line_eoln, 0 }, /* %Q */
191 	{ in_line_eoln, 0 }, /* br */
192 	{ in_line_eoln, 0 }, /* sp */
193 	{ in_line_eoln, 0 }, /* %U */
194 	{ phrase_ta, MDOC_CALLABLE | MDOC_PARSED }, /* Ta */
195 };
196 
197 const	struct mdoc_macro * const mdoc_macros = __mdoc_macros;
198 
199 
200 /*
201  * This is called at the end of parsing.  It must traverse up the tree,
202  * closing out open [implicit] scopes.  Obviously, open explicit scopes
203  * are errors.
204  */
205 int
206 mdoc_macroend(struct mdoc *m)
207 {
208 	struct mdoc_node *n;
209 
210 	/* Scan for open explicit scopes. */
211 
212 	n = MDOC_VALID & m->last->flags ?  m->last->parent : m->last;
213 
214 	for ( ; n; n = n->parent)
215 		if (MDOC_BLOCK == n->type &&
216 		    MDOC_EXPLICIT & mdoc_macros[n->tok].flags)
217 			mdoc_nmsg(m, n, MANDOCERR_SCOPEEXIT);
218 
219 	/* Rewind to the first. */
220 
221 	return(rew_last(m, m->first));
222 }
223 
224 
225 /*
226  * Look up a macro from within a subsequent context.
227  */
228 static enum mdoct
229 lookup(enum mdoct from, const char *p)
230 {
231 	/* FIXME: make -diag lists be un-PARSED. */
232 
233 	if ( ! (MDOC_PARSED & mdoc_macros[from].flags))
234 		return(MDOC_MAX);
235 	return(lookup_raw(p));
236 }
237 
238 
239 /*
240  * Lookup a macro following the initial line macro.
241  */
242 static enum mdoct
243 lookup_raw(const char *p)
244 {
245 	enum mdoct	 res;
246 
247 	if (MDOC_MAX == (res = mdoc_hash_find(p)))
248 		return(MDOC_MAX);
249 	if (MDOC_CALLABLE & mdoc_macros[res].flags)
250 		return(res);
251 	return(MDOC_MAX);
252 }
253 
254 
255 static int
256 rew_last(struct mdoc *mdoc, const struct mdoc_node *to)
257 {
258 	struct mdoc_node *n, *np;
259 
260 	assert(to);
261 	mdoc->next = MDOC_NEXT_SIBLING;
262 
263 	/* LINTED */
264 	while (mdoc->last != to) {
265 		/*
266 		 * Save the parent here, because we may delete the
267 		 * m->last node in the post-validation phase and reset
268 		 * it to m->last->parent, causing a step in the closing
269 		 * out to be lost.
270 		 */
271 		np = mdoc->last->parent;
272 		if ( ! mdoc_valid_post(mdoc))
273 			return(0);
274 		n = mdoc->last;
275 		mdoc->last = np;
276 		assert(mdoc->last);
277 		mdoc->last->last = n;
278 	}
279 
280 	return(mdoc_valid_post(mdoc));
281 }
282 
283 
284 /*
285  * For a block closing macro, return the corresponding opening one.
286  * Otherwise, return the macro itself.
287  */
288 static enum mdoct
289 rew_alt(enum mdoct tok)
290 {
291 	switch (tok) {
292 	case (MDOC_Ac):
293 		return(MDOC_Ao);
294 	case (MDOC_Bc):
295 		return(MDOC_Bo);
296 	case (MDOC_Brc):
297 		return(MDOC_Bro);
298 	case (MDOC_Dc):
299 		return(MDOC_Do);
300 	case (MDOC_Ec):
301 		return(MDOC_Eo);
302 	case (MDOC_Ed):
303 		return(MDOC_Bd);
304 	case (MDOC_Ef):
305 		return(MDOC_Bf);
306 	case (MDOC_Ek):
307 		return(MDOC_Bk);
308 	case (MDOC_El):
309 		return(MDOC_Bl);
310 	case (MDOC_Fc):
311 		return(MDOC_Fo);
312 	case (MDOC_Oc):
313 		return(MDOC_Oo);
314 	case (MDOC_Pc):
315 		return(MDOC_Po);
316 	case (MDOC_Qc):
317 		return(MDOC_Qo);
318 	case (MDOC_Re):
319 		return(MDOC_Rs);
320 	case (MDOC_Sc):
321 		return(MDOC_So);
322 	case (MDOC_Xc):
323 		return(MDOC_Xo);
324 	default:
325 		return(tok);
326 	}
327 	/* NOTREACHED */
328 }
329 
330 
331 /*
332  * Rewinding to tok, how do we have to handle *p?
333  * REWIND_NONE: *p would delimit tok, but no tok scope is open
334  *   inside *p, so there is no need to rewind anything at all.
335  * REWIND_THIS: *p matches tok, so rewind *p and nothing else.
336  * REWIND_MORE: *p is implicit, rewind it and keep searching for tok.
337  * REWIND_FORCE: *p is explicit, but tok is full, force rewinding *p.
338  * REWIND_LATER: *p is explicit and still open, postpone rewinding.
339  * REWIND_ERROR: No tok block is open at all.
340  */
341 static enum rew
342 rew_dohalt(enum mdoct tok, enum mdoc_type type,
343 		const struct mdoc_node *p)
344 {
345 
346 	/*
347 	 * No matching token, no delimiting block, no broken block.
348 	 * This can happen when full implicit macros are called for
349 	 * the first time but try to rewind their previous
350 	 * instance anyway.
351 	 */
352 	if (MDOC_ROOT == p->type)
353 		return(MDOC_BLOCK == type &&
354 		    MDOC_EXPLICIT & mdoc_macros[tok].flags ?
355 		    REWIND_ERROR : REWIND_NONE);
356 
357 	/*
358 	 * When starting to rewind, skip plain text
359 	 * and nodes that have already been rewound.
360 	 */
361 	if (MDOC_TEXT == p->type || MDOC_VALID & p->flags)
362 		return(REWIND_MORE);
363 
364 	/*
365 	 * The easiest case:  Found a matching token.
366 	 * This applies to both blocks and elements.
367 	 */
368 	tok = rew_alt(tok);
369 	if (tok == p->tok)
370 		return(p->end ? REWIND_NONE :
371 		    type == p->type ? REWIND_THIS : REWIND_MORE);
372 
373 	/*
374 	 * While elements do require rewinding for themselves,
375 	 * they never affect rewinding of other nodes.
376 	 */
377 	if (MDOC_ELEM == p->type)
378 		return(REWIND_MORE);
379 
380 	/*
381 	 * Blocks delimited by our target token get REWIND_MORE.
382 	 * Blocks delimiting our target token get REWIND_NONE.
383 	 */
384 	switch (tok) {
385 	case (MDOC_Bl):
386 		if (MDOC_It == p->tok)
387 			return(REWIND_MORE);
388 		break;
389 	case (MDOC_It):
390 		if (MDOC_BODY == p->type && MDOC_Bl == p->tok)
391 			return(REWIND_NONE);
392 		break;
393 	/*
394 	 * XXX Badly nested block handling still fails badly
395 	 * when one block is breaking two blocks of the same type.
396 	 * This is an incomplete and extremely ugly workaround,
397 	 * required to let the OpenBSD tree build.
398 	 */
399 	case (MDOC_Oo):
400 		if (MDOC_Op == p->tok)
401 			return(REWIND_MORE);
402 		break;
403 	case (MDOC_Nm):
404 		return(REWIND_NONE);
405 	case (MDOC_Nd):
406 		/* FALLTHROUGH */
407 	case (MDOC_Ss):
408 		if (MDOC_BODY == p->type && MDOC_Sh == p->tok)
409 			return(REWIND_NONE);
410 		/* FALLTHROUGH */
411 	case (MDOC_Sh):
412 		if (MDOC_Nd == p->tok || MDOC_Ss == p->tok ||
413 		    MDOC_Sh == p->tok)
414 			return(REWIND_MORE);
415 		break;
416 	default:
417 		break;
418 	}
419 
420 	/*
421 	 * Default block rewinding rules.
422 	 * In particular, always skip block end markers,
423 	 * and let all blocks rewind Nm children.
424 	 */
425 	if (ENDBODY_NOT != p->end || MDOC_Nm == p->tok ||
426 	    (MDOC_BLOCK == p->type &&
427 	    ! (MDOC_EXPLICIT & mdoc_macros[tok].flags)))
428 		return(REWIND_MORE);
429 
430 	/*
431 	 * By default, closing out full blocks
432 	 * forces closing of broken explicit blocks,
433 	 * while closing out partial blocks
434 	 * allows delayed rewinding by default.
435 	 */
436 	return (&blk_full == mdoc_macros[tok].fp ?
437 	    REWIND_FORCE : REWIND_LATER);
438 }
439 
440 
441 static int
442 rew_elem(struct mdoc *mdoc, enum mdoct tok)
443 {
444 	struct mdoc_node *n;
445 
446 	n = mdoc->last;
447 	if (MDOC_ELEM != n->type)
448 		n = n->parent;
449 	assert(MDOC_ELEM == n->type);
450 	assert(tok == n->tok);
451 
452 	return(rew_last(mdoc, n));
453 }
454 
455 
456 /*
457  * We are trying to close a block identified by tok,
458  * but the child block *broken is still open.
459  * Thus, postpone closing the tok block
460  * until the rew_sub call closing *broken.
461  */
462 static int
463 make_pending(struct mdoc_node *broken, enum mdoct tok,
464 		struct mdoc *m, int line, int ppos)
465 {
466 	struct mdoc_node *breaker;
467 
468 	/*
469 	 * Iterate backwards, searching for the block matching tok,
470 	 * that is, the block breaking the *broken block.
471 	 */
472 	for (breaker = broken->parent; breaker; breaker = breaker->parent) {
473 
474 		/*
475 		 * If the *broken block had already been broken before
476 		 * and we encounter its breaker, make the tok block
477 		 * pending on the inner breaker.
478 		 * Graphically, "[A breaker=[B broken=[C->B B] tok=A] C]"
479 		 * becomes "[A broken=[B [C->B B] tok=A] C]"
480 		 * and finally "[A [B->A [C->B B] A] C]".
481 		 */
482 		if (breaker == broken->pending) {
483 			broken = breaker;
484 			continue;
485 		}
486 
487 		if (REWIND_THIS != rew_dohalt(tok, MDOC_BLOCK, breaker))
488 			continue;
489 		if (MDOC_BODY == broken->type)
490 			broken = broken->parent;
491 
492 		/*
493 		 * Found the breaker.
494 		 * If another, outer breaker is already pending on
495 		 * the *broken block, we must not clobber the link
496 		 * to the outer breaker, but make it pending on the
497 		 * new, now inner breaker.
498 		 * Graphically, "[A breaker=[B broken=[C->A A] tok=B] C]"
499 		 * becomes "[A breaker=[B->A broken=[C A] tok=B] C]"
500 		 * and finally "[A [B->A [C->B A] B] C]".
501 		 */
502 		if (broken->pending) {
503 			struct mdoc_node *taker;
504 
505 			/*
506 			 * If the breaker had also been broken before,
507 			 * it cannot take on the outer breaker itself,
508 			 * but must hand it on to its own breakers.
509 			 * Graphically, this is the following situation:
510 			 * "[A [B breaker=[C->B B] broken=[D->A A] tok=C] D]"
511 			 * "[A taker=[B->A breaker=[C->B B] [D->C A] C] D]"
512 			 */
513 			taker = breaker;
514 			while (taker->pending)
515 				taker = taker->pending;
516 			taker->pending = broken->pending;
517 		}
518 		broken->pending = breaker;
519 		mandoc_vmsg(MANDOCERR_SCOPENEST, m->parse, line, ppos,
520 				"%s breaks %s", mdoc_macronames[tok],
521 				mdoc_macronames[broken->tok]);
522 		return(1);
523 	}
524 
525 	/*
526 	 * Found no matching block for tok.
527 	 * Are you trying to close a block that is not open?
528 	 */
529 	return(0);
530 }
531 
532 
533 static int
534 rew_sub(enum mdoc_type t, struct mdoc *m,
535 		enum mdoct tok, int line, int ppos)
536 {
537 	struct mdoc_node *n;
538 
539 	n = m->last;
540 	while (n) {
541 		switch (rew_dohalt(tok, t, n)) {
542 		case (REWIND_NONE):
543 			return(1);
544 		case (REWIND_THIS):
545 			break;
546 		case (REWIND_FORCE):
547 			mandoc_vmsg(MANDOCERR_SCOPEBROKEN, m->parse,
548 					line, ppos, "%s breaks %s",
549 					mdoc_macronames[tok],
550 					mdoc_macronames[n->tok]);
551 			/* FALLTHROUGH */
552 		case (REWIND_MORE):
553 			n = n->parent;
554 			continue;
555 		case (REWIND_LATER):
556 			if (make_pending(n, tok, m, line, ppos) ||
557 			    MDOC_BLOCK != t)
558 				return(1);
559 			/* FALLTHROUGH */
560 		case (REWIND_ERROR):
561 			mdoc_pmsg(m, line, ppos, MANDOCERR_NOSCOPE);
562 			return(1);
563 		}
564 		break;
565 	}
566 
567 	assert(n);
568 	if ( ! rew_last(m, n))
569 		return(0);
570 
571 	/*
572 	 * The current block extends an enclosing block.
573 	 * Now that the current block ends, close the enclosing block, too.
574 	 */
575 	while (NULL != (n = n->pending)) {
576 		if ( ! rew_last(m, n))
577 			return(0);
578 		if (MDOC_HEAD == n->type &&
579 		    ! mdoc_body_alloc(m, n->line, n->pos, n->tok))
580 			return(0);
581 	}
582 
583 	return(1);
584 }
585 
586 /*
587  * Allocate a word and check whether it's punctuation or not.
588  * Punctuation consists of those tokens found in mdoc_isdelim().
589  */
590 static int
591 dword(struct mdoc *m, int line,
592 		int col, const char *p, enum mdelim d)
593 {
594 
595 	if (DELIM_MAX == d)
596 		d = mdoc_isdelim(p);
597 
598 	if ( ! mdoc_word_alloc(m, line, col, p))
599 		return(0);
600 
601 	if (DELIM_OPEN == d)
602 		m->last->flags |= MDOC_DELIMO;
603 
604 	/*
605 	 * Closing delimiters only suppress the preceding space
606 	 * when they follow something, not when they start a new
607 	 * block or element, and not when they follow `No'.
608 	 *
609 	 * XXX	Explicitly special-casing MDOC_No here feels
610 	 *	like a layering violation.  Find a better way
611 	 *	and solve this in the code related to `No'!
612 	 */
613 
614 	else if (DELIM_CLOSE == d && m->last->prev &&
615 			m->last->prev->tok != MDOC_No)
616 		m->last->flags |= MDOC_DELIMC;
617 
618 	return(1);
619 }
620 
621 static int
622 append_delims(struct mdoc *m, int line, int *pos, char *buf)
623 {
624 	int		 la;
625 	enum margserr	 ac;
626 	char		*p;
627 
628 	if ('\0' == buf[*pos])
629 		return(1);
630 
631 	for (;;) {
632 		la = *pos;
633 		ac = mdoc_zargs(m, line, pos, buf, &p);
634 
635 		if (ARGS_ERROR == ac)
636 			return(0);
637 		else if (ARGS_EOLN == ac)
638 			break;
639 
640 		dword(m, line, la, p, DELIM_MAX);
641 
642 		/*
643 		 * If we encounter end-of-sentence symbols, then trigger
644 		 * the double-space.
645 		 *
646 		 * XXX: it's easy to allow this to propagate outward to
647 		 * the last symbol, such that `. )' will cause the
648 		 * correct double-spacing.  However, (1) groff isn't
649 		 * smart enough to do this and (2) it would require
650 		 * knowing which symbols break this behaviour, for
651 		 * example, `.  ;' shouldn't propagate the double-space.
652 		 */
653 		if (mandoc_eos(p, strlen(p), 0))
654 			m->last->flags |= MDOC_EOS;
655 	}
656 
657 	return(1);
658 }
659 
660 
661 /*
662  * Close out block partial/full explicit.
663  */
664 static int
665 blk_exp_close(MACRO_PROT_ARGS)
666 {
667 	struct mdoc_node *body;		/* Our own body. */
668 	struct mdoc_node *later;	/* A sub-block starting later. */
669 	struct mdoc_node *n;		/* For searching backwards. */
670 
671 	int	 	 j, lastarg, maxargs, flushed, nl;
672 	enum margserr	 ac;
673 	enum mdoct	 atok, ntok;
674 	char		*p;
675 
676 	nl = MDOC_NEWLINE & m->flags;
677 
678 	switch (tok) {
679 	case (MDOC_Ec):
680 		maxargs = 1;
681 		break;
682 	default:
683 		maxargs = 0;
684 		break;
685 	}
686 
687 	/*
688 	 * Search backwards for beginnings of blocks,
689 	 * both of our own and of pending sub-blocks.
690 	 */
691 	atok = rew_alt(tok);
692 	body = later = NULL;
693 	for (n = m->last; n; n = n->parent) {
694 		if (MDOC_VALID & n->flags)
695 			continue;
696 
697 		/* Remember the start of our own body. */
698 		if (MDOC_BODY == n->type && atok == n->tok) {
699 			if (ENDBODY_NOT == n->end)
700 				body = n;
701 			continue;
702 		}
703 
704 		if (MDOC_BLOCK != n->type || MDOC_Nm == n->tok)
705 			continue;
706 		if (atok == n->tok) {
707 			assert(body);
708 
709 			/*
710 			 * Found the start of our own block.
711 			 * When there is no pending sub block,
712 			 * just proceed to closing out.
713 			 */
714 			if (NULL == later)
715 				break;
716 
717 			/*
718 			 * When there is a pending sub block,
719 			 * postpone closing out the current block
720 			 * until the rew_sub() closing out the sub-block.
721 			 */
722 			make_pending(later, tok, m, line, ppos);
723 
724 			/*
725 			 * Mark the place where the formatting - but not
726 			 * the scope - of the current block ends.
727 			 */
728 			if ( ! mdoc_endbody_alloc(m, line, ppos,
729 			    atok, body, ENDBODY_SPACE))
730 				return(0);
731 			break;
732 		}
733 
734 		/*
735 		 * When finding an open sub block, remember the last
736 		 * open explicit block, or, in case there are only
737 		 * implicit ones, the first open implicit block.
738 		 */
739 		if (later &&
740 		    MDOC_EXPLICIT & mdoc_macros[later->tok].flags)
741 			continue;
742 		if (MDOC_CALLABLE & mdoc_macros[n->tok].flags)
743 			later = n;
744 	}
745 
746 	if ( ! (MDOC_CALLABLE & mdoc_macros[tok].flags)) {
747 		/* FIXME: do this in validate */
748 		if (buf[*pos])
749 			mdoc_pmsg(m, line, ppos, MANDOCERR_ARGSLOST);
750 
751 		if ( ! rew_sub(MDOC_BODY, m, tok, line, ppos))
752 			return(0);
753 		return(rew_sub(MDOC_BLOCK, m, tok, line, ppos));
754 	}
755 
756 	if ( ! rew_sub(MDOC_BODY, m, tok, line, ppos))
757 		return(0);
758 
759 	if (NULL == later && maxargs > 0)
760 		if ( ! mdoc_tail_alloc(m, line, ppos, rew_alt(tok)))
761 			return(0);
762 
763 	for (flushed = j = 0; ; j++) {
764 		lastarg = *pos;
765 
766 		if (j == maxargs && ! flushed) {
767 			if ( ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
768 				return(0);
769 			flushed = 1;
770 		}
771 
772 		ac = mdoc_args(m, line, pos, buf, tok, &p);
773 
774 		if (ARGS_ERROR == ac)
775 			return(0);
776 		if (ARGS_PUNCT == ac)
777 			break;
778 		if (ARGS_EOLN == ac)
779 			break;
780 
781 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup(tok, p);
782 
783 		if (MDOC_MAX == ntok) {
784 			if ( ! dword(m, line, lastarg, p, DELIM_MAX))
785 				return(0);
786 			continue;
787 		}
788 
789 		if ( ! flushed) {
790 			if ( ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
791 				return(0);
792 			flushed = 1;
793 		}
794 		if ( ! mdoc_macro(m, ntok, line, lastarg, pos, buf))
795 			return(0);
796 		break;
797 	}
798 
799 	if ( ! flushed && ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
800 		return(0);
801 
802 	if ( ! nl)
803 		return(1);
804 	return(append_delims(m, line, pos, buf));
805 }
806 
807 
808 static int
809 in_line(MACRO_PROT_ARGS)
810 {
811 	int		 la, scope, cnt, nc, nl;
812 	enum margverr	 av;
813 	enum mdoct	 ntok;
814 	enum margserr	 ac;
815 	enum mdelim	 d;
816 	struct mdoc_arg	*arg;
817 	char		*p;
818 
819 	nl = MDOC_NEWLINE & m->flags;
820 
821 	/*
822 	 * Whether we allow ignored elements (those without content,
823 	 * usually because of reserved words) to squeak by.
824 	 */
825 
826 	switch (tok) {
827 	case (MDOC_An):
828 		/* FALLTHROUGH */
829 	case (MDOC_Ar):
830 		/* FALLTHROUGH */
831 	case (MDOC_Fl):
832 		/* FALLTHROUGH */
833 	case (MDOC_Mt):
834 		/* FALLTHROUGH */
835 	case (MDOC_Nm):
836 		/* FALLTHROUGH */
837 	case (MDOC_Pa):
838 		nc = 1;
839 		break;
840 	default:
841 		nc = 0;
842 		break;
843 	}
844 
845 	for (arg = NULL;; ) {
846 		la = *pos;
847 		av = mdoc_argv(m, line, tok, &arg, pos, buf);
848 
849 		if (ARGV_WORD == av) {
850 			*pos = la;
851 			break;
852 		}
853 		if (ARGV_EOLN == av)
854 			break;
855 		if (ARGV_ARG == av)
856 			continue;
857 
858 		mdoc_argv_free(arg);
859 		return(0);
860 	}
861 
862 	for (cnt = scope = 0;; ) {
863 		la = *pos;
864 		ac = mdoc_args(m, line, pos, buf, tok, &p);
865 
866 		if (ARGS_ERROR == ac)
867 			return(0);
868 		if (ARGS_EOLN == ac)
869 			break;
870 		if (ARGS_PUNCT == ac)
871 			break;
872 
873 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup(tok, p);
874 
875 		/*
876 		 * In this case, we've located a submacro and must
877 		 * execute it.  Close out scope, if open.  If no
878 		 * elements have been generated, either create one (nc)
879 		 * or raise a warning.
880 		 */
881 
882 		if (MDOC_MAX != ntok) {
883 			if (scope && ! rew_elem(m, tok))
884 				return(0);
885 			if (nc && 0 == cnt) {
886 				if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
887 					return(0);
888 				if ( ! rew_last(m, m->last))
889 					return(0);
890 			} else if ( ! nc && 0 == cnt) {
891 				mdoc_argv_free(arg);
892 				mdoc_pmsg(m, line, ppos, MANDOCERR_MACROEMPTY);
893 			}
894 
895 			if ( ! mdoc_macro(m, ntok, line, la, pos, buf))
896 				return(0);
897 			if ( ! nl)
898 				return(1);
899 			return(append_delims(m, line, pos, buf));
900 		}
901 
902 		/*
903 		 * Non-quote-enclosed punctuation.  Set up our scope, if
904 		 * a word; rewind the scope, if a delimiter; then append
905 		 * the word.
906 		 */
907 
908 		d = ARGS_QWORD == ac ? DELIM_NONE : mdoc_isdelim(p);
909 
910 		if (DELIM_NONE != d) {
911 			/*
912 			 * If we encounter closing punctuation, no word
913 			 * has been omitted, no scope is open, and we're
914 			 * allowed to have an empty element, then start
915 			 * a new scope.  `Ar', `Fl', and `Li', only do
916 			 * this once per invocation.  There may be more
917 			 * of these (all of them?).
918 			 */
919 			if (0 == cnt && (nc || MDOC_Li == tok) &&
920 					DELIM_CLOSE == d && ! scope) {
921 				if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
922 					return(0);
923 				if (MDOC_Ar == tok || MDOC_Li == tok ||
924 						MDOC_Fl == tok)
925 					cnt++;
926 				scope = 1;
927 			}
928 			/*
929 			 * Close out our scope, if one is open, before
930 			 * any punctuation.
931 			 */
932 			if (scope && ! rew_elem(m, tok))
933 				return(0);
934 			scope = 0;
935 		} else if ( ! scope) {
936 			if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
937 				return(0);
938 			scope = 1;
939 		}
940 
941 		if (DELIM_NONE == d)
942 			cnt++;
943 
944 		if ( ! dword(m, line, la, p, d))
945 			return(0);
946 
947 		/*
948 		 * `Fl' macros have their scope re-opened with each new
949 		 * word so that the `-' can be added to each one without
950 		 * having to parse out spaces.
951 		 */
952 		if (scope && MDOC_Fl == tok) {
953 			if ( ! rew_elem(m, tok))
954 				return(0);
955 			scope = 0;
956 		}
957 	}
958 
959 	if (scope && ! rew_elem(m, tok))
960 		return(0);
961 
962 	/*
963 	 * If no elements have been collected and we're allowed to have
964 	 * empties (nc), open a scope and close it out.  Otherwise,
965 	 * raise a warning.
966 	 */
967 
968 	if (nc && 0 == cnt) {
969 		if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
970 			return(0);
971 		if ( ! rew_last(m, m->last))
972 			return(0);
973 	} else if ( ! nc && 0 == cnt) {
974 		mdoc_argv_free(arg);
975 		mdoc_pmsg(m, line, ppos, MANDOCERR_MACROEMPTY);
976 	}
977 
978 	if ( ! nl)
979 		return(1);
980 	return(append_delims(m, line, pos, buf));
981 }
982 
983 
984 static int
985 blk_full(MACRO_PROT_ARGS)
986 {
987 	int		  la, nl;
988 	struct mdoc_arg	 *arg;
989 	struct mdoc_node *head; /* save of head macro */
990 	struct mdoc_node *body; /* save of body macro */
991 	struct mdoc_node *n;
992 	enum mdoc_type	  mtt;
993 	enum mdoct	  ntok;
994 	enum margserr	  ac, lac;
995 	enum margverr	  av;
996 	char		 *p;
997 
998 	nl = MDOC_NEWLINE & m->flags;
999 
1000 	/* Close out prior implicit scope. */
1001 
1002 	if ( ! (MDOC_EXPLICIT & mdoc_macros[tok].flags)) {
1003 		if ( ! rew_sub(MDOC_BODY, m, tok, line, ppos))
1004 			return(0);
1005 		if ( ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
1006 			return(0);
1007 	}
1008 
1009 	/*
1010 	 * This routine accommodates implicitly- and explicitly-scoped
1011 	 * macro openings.  Implicit ones first close out prior scope
1012 	 * (seen above).  Delay opening the head until necessary to
1013 	 * allow leading punctuation to print.  Special consideration
1014 	 * for `It -column', which has phrase-part syntax instead of
1015 	 * regular child nodes.
1016 	 */
1017 
1018 	for (arg = NULL;; ) {
1019 		la = *pos;
1020 		av = mdoc_argv(m, line, tok, &arg, pos, buf);
1021 
1022 		if (ARGV_WORD == av) {
1023 			*pos = la;
1024 			break;
1025 		}
1026 
1027 		if (ARGV_EOLN == av)
1028 			break;
1029 		if (ARGV_ARG == av)
1030 			continue;
1031 
1032 		mdoc_argv_free(arg);
1033 		return(0);
1034 	}
1035 
1036 	if ( ! mdoc_block_alloc(m, line, ppos, tok, arg))
1037 		return(0);
1038 
1039 	head = body = NULL;
1040 
1041 	/*
1042 	 * The `Nd' macro has all arguments in its body: it's a hybrid
1043 	 * of block partial-explicit and full-implicit.  Stupid.
1044 	 */
1045 
1046 	if (MDOC_Nd == tok) {
1047 		if ( ! mdoc_head_alloc(m, line, ppos, tok))
1048 			return(0);
1049 		head = m->last;
1050 		if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
1051 			return(0);
1052 		if ( ! mdoc_body_alloc(m, line, ppos, tok))
1053 			return(0);
1054 		body = m->last;
1055 	}
1056 
1057 	ac = ARGS_ERROR;
1058 
1059 	for ( ; ; ) {
1060 		la = *pos;
1061 		/* Initialise last-phrase-type with ARGS_PEND. */
1062 		lac = ARGS_ERROR == ac ? ARGS_PEND : ac;
1063 		ac = mdoc_args(m, line, pos, buf, tok, &p);
1064 
1065 		if (ARGS_PUNCT == ac)
1066 			break;
1067 
1068 		if (ARGS_ERROR == ac)
1069 			return(0);
1070 
1071 		if (ARGS_EOLN == ac) {
1072 			if (ARGS_PPHRASE != lac && ARGS_PHRASE != lac)
1073 				break;
1074 			/*
1075 			 * This is necessary: if the last token on a
1076 			 * line is a `Ta' or tab, then we'll get
1077 			 * ARGS_EOLN, so we must be smart enough to
1078 			 * reopen our scope if the last parse was a
1079 			 * phrase or partial phrase.
1080 			 */
1081 			if ( ! rew_sub(MDOC_BODY, m, tok, line, ppos))
1082 				return(0);
1083 			if ( ! mdoc_body_alloc(m, line, ppos, tok))
1084 				return(0);
1085 			body = m->last;
1086 			break;
1087 		}
1088 
1089 		/*
1090 		 * Emit leading punctuation (i.e., punctuation before
1091 		 * the MDOC_HEAD) for non-phrase types.
1092 		 */
1093 
1094 		if (NULL == head &&
1095 				ARGS_PEND != ac &&
1096 				ARGS_PHRASE != ac &&
1097 				ARGS_PPHRASE != ac &&
1098 				ARGS_QWORD != ac &&
1099 				DELIM_OPEN == mdoc_isdelim(p)) {
1100 			if ( ! dword(m, line, la, p, DELIM_OPEN))
1101 				return(0);
1102 			continue;
1103 		}
1104 
1105 		/* Open a head if one hasn't been opened. */
1106 
1107 		if (NULL == head) {
1108 			if ( ! mdoc_head_alloc(m, line, ppos, tok))
1109 				return(0);
1110 			head = m->last;
1111 		}
1112 
1113 		if (ARGS_PHRASE == ac ||
1114 				ARGS_PEND == ac ||
1115 				ARGS_PPHRASE == ac) {
1116 			/*
1117 			 * If we haven't opened a body yet, rewind the
1118 			 * head; if we have, rewind that instead.
1119 			 */
1120 
1121 			mtt = body ? MDOC_BODY : MDOC_HEAD;
1122 			if ( ! rew_sub(mtt, m, tok, line, ppos))
1123 				return(0);
1124 
1125 			/* Then allocate our body context. */
1126 
1127 			if ( ! mdoc_body_alloc(m, line, ppos, tok))
1128 				return(0);
1129 			body = m->last;
1130 
1131 			/*
1132 			 * Process phrases: set whether we're in a
1133 			 * partial-phrase (this effects line handling)
1134 			 * then call down into the phrase parser.
1135 			 */
1136 
1137 			if (ARGS_PPHRASE == ac)
1138 				m->flags |= MDOC_PPHRASE;
1139 			if (ARGS_PEND == ac && ARGS_PPHRASE == lac)
1140 				m->flags |= MDOC_PPHRASE;
1141 
1142 			if ( ! phrase(m, line, la, buf))
1143 				return(0);
1144 
1145 			m->flags &= ~MDOC_PPHRASE;
1146 			continue;
1147 		}
1148 
1149 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup(tok, p);
1150 
1151 		if (MDOC_MAX == ntok) {
1152 			if ( ! dword(m, line, la, p, DELIM_MAX))
1153 				return(0);
1154 			continue;
1155 		}
1156 
1157 		if ( ! mdoc_macro(m, ntok, line, la, pos, buf))
1158 			return(0);
1159 		break;
1160 	}
1161 
1162 	if (NULL == head) {
1163 		if ( ! mdoc_head_alloc(m, line, ppos, tok))
1164 			return(0);
1165 		head = m->last;
1166 	}
1167 
1168 	if (nl && ! append_delims(m, line, pos, buf))
1169 		return(0);
1170 
1171 	/* If we've already opened our body, exit now. */
1172 
1173 	if (NULL != body)
1174 		goto out;
1175 
1176 	/*
1177 	 * If there is an open (i.e., unvalidated) sub-block requiring
1178 	 * explicit close-out, postpone switching the current block from
1179 	 * head to body until the rew_sub() call closing out that
1180 	 * sub-block.
1181 	 */
1182 	for (n = m->last; n && n != head; n = n->parent) {
1183 		if (MDOC_BLOCK == n->type &&
1184 				MDOC_EXPLICIT & mdoc_macros[n->tok].flags &&
1185 				! (MDOC_VALID & n->flags)) {
1186 			n->pending = head;
1187 			return(1);
1188 		}
1189 	}
1190 
1191 	/* Close out scopes to remain in a consistent state. */
1192 
1193 	if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
1194 		return(0);
1195 	if ( ! mdoc_body_alloc(m, line, ppos, tok))
1196 		return(0);
1197 
1198 out:
1199 	if ( ! (MDOC_FREECOL & m->flags))
1200 		return(1);
1201 
1202 	if ( ! rew_sub(MDOC_BODY, m, tok, line, ppos))
1203 		return(0);
1204 	if ( ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
1205 		return(0);
1206 
1207 	m->flags &= ~MDOC_FREECOL;
1208 	return(1);
1209 }
1210 
1211 
1212 static int
1213 blk_part_imp(MACRO_PROT_ARGS)
1214 {
1215 	int		  la, nl;
1216 	enum mdoct	  ntok;
1217 	enum margserr	  ac;
1218 	char		 *p;
1219 	struct mdoc_node *blk; /* saved block context */
1220 	struct mdoc_node *body; /* saved body context */
1221 	struct mdoc_node *n;
1222 
1223 	nl = MDOC_NEWLINE & m->flags;
1224 
1225 	/*
1226 	 * A macro that spans to the end of the line.  This is generally
1227 	 * (but not necessarily) called as the first macro.  The block
1228 	 * has a head as the immediate child, which is always empty,
1229 	 * followed by zero or more opening punctuation nodes, then the
1230 	 * body (which may be empty, depending on the macro), then zero
1231 	 * or more closing punctuation nodes.
1232 	 */
1233 
1234 	if ( ! mdoc_block_alloc(m, line, ppos, tok, NULL))
1235 		return(0);
1236 
1237 	blk = m->last;
1238 
1239 	if ( ! mdoc_head_alloc(m, line, ppos, tok))
1240 		return(0);
1241 	if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
1242 		return(0);
1243 
1244 	/*
1245 	 * Open the body scope "on-demand", that is, after we've
1246 	 * processed all our the leading delimiters (open parenthesis,
1247 	 * etc.).
1248 	 */
1249 
1250 	for (body = NULL; ; ) {
1251 		la = *pos;
1252 		ac = mdoc_args(m, line, pos, buf, tok, &p);
1253 
1254 		if (ARGS_ERROR == ac)
1255 			return(0);
1256 		if (ARGS_EOLN == ac)
1257 			break;
1258 		if (ARGS_PUNCT == ac)
1259 			break;
1260 
1261 		if (NULL == body && ARGS_QWORD != ac &&
1262 				DELIM_OPEN == mdoc_isdelim(p)) {
1263 			if ( ! dword(m, line, la, p, DELIM_OPEN))
1264 				return(0);
1265 			continue;
1266 		}
1267 
1268 		if (NULL == body) {
1269 		       if ( ! mdoc_body_alloc(m, line, ppos, tok))
1270 			       return(0);
1271 			body = m->last;
1272 		}
1273 
1274 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup(tok, p);
1275 
1276 		if (MDOC_MAX == ntok) {
1277 			if ( ! dword(m, line, la, p, DELIM_MAX))
1278 				return(0);
1279 			continue;
1280 		}
1281 
1282 		if ( ! mdoc_macro(m, ntok, line, la, pos, buf))
1283 			return(0);
1284 		break;
1285 	}
1286 
1287 	/* Clean-ups to leave in a consistent state. */
1288 
1289 	if (NULL == body) {
1290 		if ( ! mdoc_body_alloc(m, line, ppos, tok))
1291 			return(0);
1292 		body = m->last;
1293 	}
1294 
1295 	for (n = body->child; n && n->next; n = n->next)
1296 		/* Do nothing. */ ;
1297 
1298 	/*
1299 	 * End of sentence spacing: if the last node is a text node and
1300 	 * has a trailing period, then mark it as being end-of-sentence.
1301 	 */
1302 
1303 	if (n && MDOC_TEXT == n->type && n->string)
1304 		if (mandoc_eos(n->string, strlen(n->string), 1))
1305 			n->flags |= MDOC_EOS;
1306 
1307 	/* Up-propagate the end-of-space flag. */
1308 
1309 	if (n && (MDOC_EOS & n->flags)) {
1310 		body->flags |= MDOC_EOS;
1311 		body->parent->flags |= MDOC_EOS;
1312 	}
1313 
1314 	/*
1315 	 * If there is an open sub-block requiring explicit close-out,
1316 	 * postpone closing out the current block
1317 	 * until the rew_sub() call closing out the sub-block.
1318 	 */
1319 	for (n = m->last; n && n != body && n != blk->parent; n = n->parent) {
1320 		if (MDOC_BLOCK == n->type &&
1321 		    MDOC_EXPLICIT & mdoc_macros[n->tok].flags &&
1322 		    ! (MDOC_VALID & n->flags)) {
1323 			make_pending(n, tok, m, line, ppos);
1324 			if ( ! mdoc_endbody_alloc(m, line, ppos,
1325 			    tok, body, ENDBODY_NOSPACE))
1326 				return(0);
1327 			return(1);
1328 		}
1329 	}
1330 
1331 	/*
1332 	 * If we can't rewind to our body, then our scope has already
1333 	 * been closed by another macro (like `Oc' closing `Op').  This
1334 	 * is ugly behaviour nodding its head to OpenBSD's overwhelming
1335 	 * crufty use of `Op' breakage.
1336 	 */
1337 	if (n != body)
1338 		mandoc_vmsg(MANDOCERR_SCOPENEST, m->parse, line, ppos,
1339 				"%s broken", mdoc_macronames[tok]);
1340 
1341 	if (n && ! rew_sub(MDOC_BODY, m, tok, line, ppos))
1342 		return(0);
1343 
1344 	/* Standard appending of delimiters. */
1345 
1346 	if (nl && ! append_delims(m, line, pos, buf))
1347 		return(0);
1348 
1349 	/* Rewind scope, if applicable. */
1350 
1351 	if (n && ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
1352 		return(0);
1353 
1354 	return(1);
1355 }
1356 
1357 
1358 static int
1359 blk_part_exp(MACRO_PROT_ARGS)
1360 {
1361 	int		  la, nl;
1362 	enum margserr	  ac;
1363 	struct mdoc_node *head; /* keep track of head */
1364 	struct mdoc_node *body; /* keep track of body */
1365 	char		 *p;
1366 	enum mdoct	  ntok;
1367 
1368 	nl = MDOC_NEWLINE & m->flags;
1369 
1370 	/*
1371 	 * The opening of an explicit macro having zero or more leading
1372 	 * punctuation nodes; a head with optional single element (the
1373 	 * case of `Eo'); and a body that may be empty.
1374 	 */
1375 
1376 	if ( ! mdoc_block_alloc(m, line, ppos, tok, NULL))
1377 		return(0);
1378 
1379 	for (head = body = NULL; ; ) {
1380 		la = *pos;
1381 		ac = mdoc_args(m, line, pos, buf, tok, &p);
1382 
1383 		if (ARGS_ERROR == ac)
1384 			return(0);
1385 		if (ARGS_PUNCT == ac)
1386 			break;
1387 		if (ARGS_EOLN == ac)
1388 			break;
1389 
1390 		/* Flush out leading punctuation. */
1391 
1392 		if (NULL == head && ARGS_QWORD != ac &&
1393 				DELIM_OPEN == mdoc_isdelim(p)) {
1394 			assert(NULL == body);
1395 			if ( ! dword(m, line, la, p, DELIM_OPEN))
1396 				return(0);
1397 			continue;
1398 		}
1399 
1400 		if (NULL == head) {
1401 			assert(NULL == body);
1402 			if ( ! mdoc_head_alloc(m, line, ppos, tok))
1403 				return(0);
1404 			head = m->last;
1405 		}
1406 
1407 		/*
1408 		 * `Eo' gobbles any data into the head, but most other
1409 		 * macros just immediately close out and begin the body.
1410 		 */
1411 
1412 		if (NULL == body) {
1413 			assert(head);
1414 			/* No check whether it's a macro! */
1415 			if (MDOC_Eo == tok)
1416 				if ( ! dword(m, line, la, p, DELIM_MAX))
1417 					return(0);
1418 
1419 			if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
1420 				return(0);
1421 			if ( ! mdoc_body_alloc(m, line, ppos, tok))
1422 				return(0);
1423 			body = m->last;
1424 
1425 			if (MDOC_Eo == tok)
1426 				continue;
1427 		}
1428 
1429 		assert(NULL != head && NULL != body);
1430 
1431 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup(tok, p);
1432 
1433 		if (MDOC_MAX == ntok) {
1434 			if ( ! dword(m, line, la, p, DELIM_MAX))
1435 				return(0);
1436 			continue;
1437 		}
1438 
1439 		if ( ! mdoc_macro(m, ntok, line, la, pos, buf))
1440 			return(0);
1441 		break;
1442 	}
1443 
1444 	/* Clean-up to leave in a consistent state. */
1445 
1446 	if (NULL == head) {
1447 		if ( ! mdoc_head_alloc(m, line, ppos, tok))
1448 			return(0);
1449 		head = m->last;
1450 	}
1451 
1452 	if (NULL == body) {
1453 		if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
1454 			return(0);
1455 		if ( ! mdoc_body_alloc(m, line, ppos, tok))
1456 			return(0);
1457 		body = m->last;
1458 	}
1459 
1460 	/* Standard appending of delimiters. */
1461 
1462 	if ( ! nl)
1463 		return(1);
1464 	return(append_delims(m, line, pos, buf));
1465 }
1466 
1467 
1468 /* ARGSUSED */
1469 static int
1470 in_line_argn(MACRO_PROT_ARGS)
1471 {
1472 	int		 la, flushed, j, maxargs, nl;
1473 	enum margserr	 ac;
1474 	enum margverr	 av;
1475 	struct mdoc_arg	*arg;
1476 	char		*p;
1477 	enum mdoct	 ntok;
1478 
1479 	nl = MDOC_NEWLINE & m->flags;
1480 
1481 	/*
1482 	 * A line macro that has a fixed number of arguments (maxargs).
1483 	 * Only open the scope once the first non-leading-punctuation is
1484 	 * found (unless MDOC_IGNDELIM is noted, like in `Pf'), then
1485 	 * keep it open until the maximum number of arguments are
1486 	 * exhausted.
1487 	 */
1488 
1489 	switch (tok) {
1490 	case (MDOC_Ap):
1491 		/* FALLTHROUGH */
1492 	case (MDOC_No):
1493 		/* FALLTHROUGH */
1494 	case (MDOC_Ns):
1495 		/* FALLTHROUGH */
1496 	case (MDOC_Ux):
1497 		maxargs = 0;
1498 		break;
1499 	case (MDOC_Bx):
1500 		/* FALLTHROUGH */
1501 	case (MDOC_Xr):
1502 		maxargs = 2;
1503 		break;
1504 	default:
1505 		maxargs = 1;
1506 		break;
1507 	}
1508 
1509 	for (arg = NULL; ; ) {
1510 		la = *pos;
1511 		av = mdoc_argv(m, line, tok, &arg, pos, buf);
1512 
1513 		if (ARGV_WORD == av) {
1514 			*pos = la;
1515 			break;
1516 		}
1517 
1518 		if (ARGV_EOLN == av)
1519 			break;
1520 		if (ARGV_ARG == av)
1521 			continue;
1522 
1523 		mdoc_argv_free(arg);
1524 		return(0);
1525 	}
1526 
1527 	for (flushed = j = 0; ; ) {
1528 		la = *pos;
1529 		ac = mdoc_args(m, line, pos, buf, tok, &p);
1530 
1531 		if (ARGS_ERROR == ac)
1532 			return(0);
1533 		if (ARGS_PUNCT == ac)
1534 			break;
1535 		if (ARGS_EOLN == ac)
1536 			break;
1537 
1538 		if ( ! (MDOC_IGNDELIM & mdoc_macros[tok].flags) &&
1539 				ARGS_QWORD != ac && 0 == j &&
1540 				DELIM_OPEN == mdoc_isdelim(p)) {
1541 			if ( ! dword(m, line, la, p, DELIM_OPEN))
1542 				return(0);
1543 			continue;
1544 		} else if (0 == j)
1545 		       if ( ! mdoc_elem_alloc(m, line, la, tok, arg))
1546 			       return(0);
1547 
1548 		if (j == maxargs && ! flushed) {
1549 			if ( ! rew_elem(m, tok))
1550 				return(0);
1551 			flushed = 1;
1552 		}
1553 
1554 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup(tok, p);
1555 
1556 		if (MDOC_MAX != ntok) {
1557 			if ( ! flushed && ! rew_elem(m, tok))
1558 				return(0);
1559 			flushed = 1;
1560 			if ( ! mdoc_macro(m, ntok, line, la, pos, buf))
1561 				return(0);
1562 			j++;
1563 			break;
1564 		}
1565 
1566 		if ( ! (MDOC_IGNDELIM & mdoc_macros[tok].flags) &&
1567 				ARGS_QWORD != ac &&
1568 				! flushed &&
1569 				DELIM_NONE != mdoc_isdelim(p)) {
1570 			if ( ! rew_elem(m, tok))
1571 				return(0);
1572 			flushed = 1;
1573 		}
1574 
1575 		/*
1576 		 * XXX: this is a hack to work around groff's ugliness
1577 		 * as regards `Xr' and extraneous arguments.  It should
1578 		 * ideally be deprecated behaviour, but because this is
1579 		 * code is no here, it's unlikely to be removed.
1580 		 */
1581 
1582 #ifdef __OpenBSD__
1583 		if (MDOC_Xr == tok && j == maxargs) {
1584 			if ( ! mdoc_elem_alloc(m, line, la, MDOC_Ns, NULL))
1585 				return(0);
1586 			if ( ! rew_elem(m, MDOC_Ns))
1587 				return(0);
1588 		}
1589 #endif
1590 
1591 		if ( ! dword(m, line, la, p, DELIM_MAX))
1592 			return(0);
1593 		j++;
1594 	}
1595 
1596 	if (0 == j && ! mdoc_elem_alloc(m, line, la, tok, arg))
1597 	       return(0);
1598 
1599 	/* Close out in a consistent state. */
1600 
1601 	if ( ! flushed && ! rew_elem(m, tok))
1602 		return(0);
1603 	if ( ! nl)
1604 		return(1);
1605 	return(append_delims(m, line, pos, buf));
1606 }
1607 
1608 
1609 static int
1610 in_line_eoln(MACRO_PROT_ARGS)
1611 {
1612 	int		 la;
1613 	enum margserr	 ac;
1614 	enum margverr	 av;
1615 	struct mdoc_arg	*arg;
1616 	char		*p;
1617 	enum mdoct	 ntok;
1618 
1619 	assert( ! (MDOC_PARSED & mdoc_macros[tok].flags));
1620 
1621 	if (tok == MDOC_Pp)
1622 		rew_sub(MDOC_BLOCK, m, MDOC_Nm, line, ppos);
1623 
1624 	/* Parse macro arguments. */
1625 
1626 	for (arg = NULL; ; ) {
1627 		la = *pos;
1628 		av = mdoc_argv(m, line, tok, &arg, pos, buf);
1629 
1630 		if (ARGV_WORD == av) {
1631 			*pos = la;
1632 			break;
1633 		}
1634 		if (ARGV_EOLN == av)
1635 			break;
1636 		if (ARGV_ARG == av)
1637 			continue;
1638 
1639 		mdoc_argv_free(arg);
1640 		return(0);
1641 	}
1642 
1643 	/* Open element scope. */
1644 
1645 	if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
1646 		return(0);
1647 
1648 	/* Parse argument terms. */
1649 
1650 	for (;;) {
1651 		la = *pos;
1652 		ac = mdoc_args(m, line, pos, buf, tok, &p);
1653 
1654 		if (ARGS_ERROR == ac)
1655 			return(0);
1656 		if (ARGS_EOLN == ac)
1657 			break;
1658 
1659 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup(tok, p);
1660 
1661 		if (MDOC_MAX == ntok) {
1662 			if ( ! dword(m, line, la, p, DELIM_MAX))
1663 				return(0);
1664 			continue;
1665 		}
1666 
1667 		if ( ! rew_elem(m, tok))
1668 			return(0);
1669 		return(mdoc_macro(m, ntok, line, la, pos, buf));
1670 	}
1671 
1672 	/* Close out (no delimiters). */
1673 
1674 	return(rew_elem(m, tok));
1675 }
1676 
1677 
1678 /* ARGSUSED */
1679 static int
1680 ctx_synopsis(MACRO_PROT_ARGS)
1681 {
1682 	int		 nl;
1683 
1684 	nl = MDOC_NEWLINE & m->flags;
1685 
1686 	/* If we're not in the SYNOPSIS, go straight to in-line. */
1687 	if ( ! (MDOC_SYNOPSIS & m->flags))
1688 		return(in_line(m, tok, line, ppos, pos, buf));
1689 
1690 	/* If we're a nested call, same place. */
1691 	if ( ! nl)
1692 		return(in_line(m, tok, line, ppos, pos, buf));
1693 
1694 	/*
1695 	 * XXX: this will open a block scope; however, if later we end
1696 	 * up formatting the block scope, then child nodes will inherit
1697 	 * the formatting.  Be careful.
1698 	 */
1699 	if (MDOC_Nm == tok)
1700 		return(blk_full(m, tok, line, ppos, pos, buf));
1701 	assert(MDOC_Vt == tok);
1702 	return(blk_part_imp(m, tok, line, ppos, pos, buf));
1703 }
1704 
1705 
1706 /* ARGSUSED */
1707 static int
1708 obsolete(MACRO_PROT_ARGS)
1709 {
1710 
1711 	mdoc_pmsg(m, line, ppos, MANDOCERR_MACROOBS);
1712 	return(1);
1713 }
1714 
1715 
1716 /*
1717  * Phrases occur within `Bl -column' entries, separated by `Ta' or tabs.
1718  * They're unusual because they're basically free-form text until a
1719  * macro is encountered.
1720  */
1721 static int
1722 phrase(struct mdoc *m, int line, int ppos, char *buf)
1723 {
1724 	int		 la, pos;
1725 	enum margserr	 ac;
1726 	enum mdoct	 ntok;
1727 	char		*p;
1728 
1729 	for (pos = ppos; ; ) {
1730 		la = pos;
1731 
1732 		ac = mdoc_zargs(m, line, &pos, buf, &p);
1733 
1734 		if (ARGS_ERROR == ac)
1735 			return(0);
1736 		if (ARGS_EOLN == ac)
1737 			break;
1738 
1739 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup_raw(p);
1740 
1741 		if (MDOC_MAX == ntok) {
1742 			if ( ! dword(m, line, la, p, DELIM_MAX))
1743 				return(0);
1744 			continue;
1745 		}
1746 
1747 		if ( ! mdoc_macro(m, ntok, line, la, &pos, buf))
1748 			return(0);
1749 		return(append_delims(m, line, &pos, buf));
1750 	}
1751 
1752 	return(1);
1753 }
1754 
1755 
1756 /* ARGSUSED */
1757 static int
1758 phrase_ta(MACRO_PROT_ARGS)
1759 {
1760 	int		  la;
1761 	enum mdoct	  ntok;
1762 	enum margserr	  ac;
1763 	char		 *p;
1764 
1765 	/*
1766 	 * FIXME: this is overly restrictive: if the `Ta' is unexpected,
1767 	 * it should simply error out with ARGSLOST.
1768 	 */
1769 
1770 	if ( ! rew_sub(MDOC_BODY, m, MDOC_It, line, ppos))
1771 		return(0);
1772 	if ( ! mdoc_body_alloc(m, line, ppos, MDOC_It))
1773 		return(0);
1774 
1775 	for (;;) {
1776 		la = *pos;
1777 		ac = mdoc_zargs(m, line, pos, buf, &p);
1778 
1779 		if (ARGS_ERROR == ac)
1780 			return(0);
1781 		if (ARGS_EOLN == ac)
1782 			break;
1783 
1784 		ntok = ARGS_QWORD == ac ? MDOC_MAX : lookup_raw(p);
1785 
1786 		if (MDOC_MAX == ntok) {
1787 			if ( ! dword(m, line, la, p, DELIM_MAX))
1788 				return(0);
1789 			continue;
1790 		}
1791 
1792 		if ( ! mdoc_macro(m, ntok, line, la, pos, buf))
1793 			return(0);
1794 		return(append_delims(m, line, pos, buf));
1795 	}
1796 
1797 	return(1);
1798 }
1799