xref: /freebsd/sbin/rcorder/rcorder.c (revision 1f4bcc459a76b7aa664f3fd557684cd0ba6da352)
1 # if 0
2 /*	$NetBSD: rcorder.c,v 1.7 2000/08/04 07:33:55 enami Exp $	*/
3 #endif
4 
5 /*
6  * Copyright (c) 1998, 1999 Matthew R. Green
7  * All rights reserved.
8  * Copyright (c) 1998
9  * 	Perry E. Metzger.  All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed for the NetBSD Project
22  *	by Perry E. Metzger.
23  * 4. The name of the author may not be used to endorse or promote products
24  *    derived from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #include <sys/types.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include <sys/stat.h>
42 
43 #include <err.h>
44 #include <stdio.h>
45 #include <libutil.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include "ealloc.h"
51 #include "sprite.h"
52 #include "hash.h"
53 
54 #ifdef DEBUG
55 static int debug = 0;
56 # define	DPRINTF(args) if (debug) { fflush(stdout); fprintf args; }
57 #else
58 # define	DPRINTF(args)
59 #endif
60 
61 #define REQUIRE_STR	"# REQUIRE:"
62 #define REQUIRE_LEN	(sizeof(REQUIRE_STR) - 1)
63 #define REQUIRES_STR	"# REQUIRES:"
64 #define REQUIRES_LEN	(sizeof(REQUIRES_STR) - 1)
65 #define PROVIDE_STR	"# PROVIDE:"
66 #define PROVIDE_LEN	(sizeof(PROVIDE_STR) - 1)
67 #define PROVIDES_STR	"# PROVIDES:"
68 #define PROVIDES_LEN	(sizeof(PROVIDES_STR) - 1)
69 #define BEFORE_STR	"# BEFORE:"
70 #define BEFORE_LEN	(sizeof(BEFORE_STR) - 1)
71 #define KEYWORD_STR	"# KEYWORD:"
72 #define KEYWORD_LEN	(sizeof(KEYWORD_STR) - 1)
73 #define KEYWORDS_STR	"# KEYWORDS:"
74 #define KEYWORDS_LEN	(sizeof(KEYWORDS_STR) - 1)
75 
76 static int exit_code;
77 static int file_count;
78 static char **file_list;
79 
80 typedef int bool;
81 #define TRUE 1
82 #define FALSE 0
83 typedef bool flag;
84 #define SET TRUE
85 #define RESET FALSE
86 
87 static Hash_Table provide_hash_s, *provide_hash;
88 
89 typedef struct provnode provnode;
90 typedef struct filenode filenode;
91 typedef struct f_provnode f_provnode;
92 typedef struct f_reqnode f_reqnode;
93 typedef struct strnodelist strnodelist;
94 
95 struct provnode {
96 	flag		head;
97 	flag		in_progress;
98 	filenode	*fnode;
99 	provnode	*next, *last;
100 };
101 
102 struct f_provnode {
103 	provnode	*pnode;
104 	f_provnode	*next;
105 };
106 
107 struct f_reqnode {
108 	Hash_Entry	*entry;
109 	f_reqnode	*next;
110 };
111 
112 struct strnodelist {
113 	filenode	*node;
114 	strnodelist	*next;
115 	char		s[1];
116 };
117 
118 struct filenode {
119 	char		*filename;
120 	flag		in_progress;
121 	filenode	*next, *last;
122 	f_reqnode	*req_list;
123 	f_provnode	*prov_list;
124 	strnodelist	*keyword_list;
125 };
126 
127 static filenode fn_head_s, *fn_head;
128 
129 static strnodelist *bl_list;
130 static strnodelist *keep_list;
131 static strnodelist *skip_list;
132 
133 static void do_file(filenode *fnode);
134 static void strnode_add(strnodelist **, char *, filenode *);
135 static int skip_ok(filenode *fnode);
136 static int keep_ok(filenode *fnode);
137 static void satisfy_req(f_reqnode *rnode, char *filename);
138 static void crunch_file(char *);
139 static void parse_require(filenode *, char *);
140 static void parse_provide(filenode *, char *);
141 static void parse_before(filenode *, char *);
142 static void parse_keywords(filenode *, char *);
143 static filenode *filenode_new(char *);
144 static void add_require(filenode *, char *);
145 static void add_provide(filenode *, char *);
146 static void add_before(filenode *, char *);
147 static void add_keyword(filenode *, char *);
148 static void insert_before(void);
149 static Hash_Entry *make_fake_provision(filenode *);
150 static void crunch_all_files(void);
151 static void initialize(void);
152 static void generate_ordering(void);
153 
154 int
155 main(int argc, char *argv[])
156 {
157 	int ch;
158 
159 	while ((ch = getopt(argc, argv, "dk:s:")) != -1)
160 		switch (ch) {
161 		case 'd':
162 #ifdef DEBUG
163 			debug = 1;
164 #else
165 			warnx("debugging not compiled in, -d ignored");
166 #endif
167 			break;
168 		case 'k':
169 			strnode_add(&keep_list, optarg, 0);
170 			break;
171 		case 's':
172 			strnode_add(&skip_list, optarg, 0);
173 			break;
174 		default:
175 			/* XXX should crunch it? */
176 			break;
177 		}
178 	argc -= optind;
179 	argv += optind;
180 
181 	file_count = argc;
182 	file_list = argv;
183 
184 	DPRINTF((stderr, "parse_args\n"));
185 	initialize();
186 	DPRINTF((stderr, "initialize\n"));
187 	crunch_all_files();
188 	DPRINTF((stderr, "crunch_all_files\n"));
189 	generate_ordering();
190 	DPRINTF((stderr, "generate_ordering\n"));
191 
192 	exit(exit_code);
193 }
194 
195 /*
196  * initialise various variables.
197  */
198 static void
199 initialize(void)
200 {
201 
202 	fn_head = &fn_head_s;
203 
204 	provide_hash = &provide_hash_s;
205 	Hash_InitTable(provide_hash, file_count);
206 }
207 
208 /* generic function to insert a new strnodelist element */
209 static void
210 strnode_add(strnodelist **listp, char *s, filenode *fnode)
211 {
212 	strnodelist *ent;
213 
214 	ent = emalloc(sizeof *ent + strlen(s));
215 	ent->node = fnode;
216 	strcpy(ent->s, s);
217 	ent->next = *listp;
218 	*listp = ent;
219 }
220 
221 /*
222  * below are the functions that deal with creating the lists
223  * from the filename's given dependencies and provisions
224  * in each of these files.  no ordering or checking is done here.
225  */
226 
227 /*
228  * we have a new filename, create a new filenode structure.
229  * fill in the bits, and put it in the filenode linked list
230  */
231 static filenode *
232 filenode_new(char *filename)
233 {
234 	filenode *temp;
235 
236 	temp = emalloc(sizeof(*temp));
237 	memset(temp, 0, sizeof(*temp));
238 	temp->filename = estrdup(filename);
239 	temp->req_list = NULL;
240 	temp->prov_list = NULL;
241 	temp->keyword_list = NULL;
242 	temp->in_progress = RESET;
243 	/*
244 	 * link the filenode into the list of filenodes.
245 	 * note that the double linking means we can delete a
246 	 * filenode without searching for where it belongs.
247 	 */
248 	temp->next = fn_head->next;
249 	if (temp->next != NULL)
250 		temp->next->last = temp;
251 	temp->last = fn_head;
252 	fn_head->next = temp;
253 	return (temp);
254 }
255 
256 /*
257  * add a requirement to a filenode.
258  */
259 static void
260 add_require(filenode *fnode, char *s)
261 {
262 	Hash_Entry *entry;
263 	f_reqnode *rnode;
264 	int new;
265 
266 	entry = Hash_CreateEntry(provide_hash, s, &new);
267 	if (new)
268 		Hash_SetValue(entry, NULL);
269 	rnode = emalloc(sizeof(*rnode));
270 	rnode->entry = entry;
271 	rnode->next = fnode->req_list;
272 	fnode->req_list = rnode;
273 }
274 
275 /*
276  * add a provision to a filenode.  if this provision doesn't
277  * have a head node, create one here.
278  */
279 static void
280 add_provide(filenode *fnode, char *s)
281 {
282 	Hash_Entry *entry;
283 	f_provnode *f_pnode;
284 	provnode *pnode, *head;
285 	int new;
286 
287 	entry = Hash_CreateEntry(provide_hash, s, &new);
288 	head = Hash_GetValue(entry);
289 
290 	/* create a head node if necessary. */
291 	if (head == NULL) {
292 		head = emalloc(sizeof(*head));
293 		head->head = SET;
294 		head->in_progress = RESET;
295 		head->fnode = NULL;
296 		head->last = head->next = NULL;
297 		Hash_SetValue(entry, head);
298 	}
299 #if 0
300 	/*
301 	 * Don't warn about this.  We want to be able to support
302 	 * scripts that do two complex things:
303 	 *
304 	 *	- Two independent scripts which both provide the
305 	 *	  same thing.  Both scripts must be executed in
306 	 *	  any order to meet the barrier.  An example:
307 	 *
308 	 *		Script 1:
309 	 *
310 	 *			PROVIDE: mail
311 	 *			REQUIRE: LOGIN
312 	 *
313 	 *		Script 2:
314 	 *
315 	 *			PROVIDE: mail
316 	 *			REQUIRE: LOGIN
317 	 *
318 	 * 	- Two interdependent scripts which both provide the
319 	 *	  same thing.  Both scripts must be executed in
320 	 *	  graph order to meet the barrier.  An example:
321 	 *
322 	 *		Script 1:
323 	 *
324 	 *			PROVIDE: nameservice dnscache
325 	 *			REQUIRE: SERVERS
326 	 *
327 	 *		Script 2:
328 	 *
329 	 *			PROVIDE: nameservice nscd
330 	 *			REQUIRE: dnscache
331 	 */
332 	else if (new == 0) {
333 		warnx("file `%s' provides `%s'.", fnode->filename, s);
334 		warnx("\tpreviously seen in `%s'.",
335 		    head->next->fnode->filename);
336 	}
337 #endif
338 
339 	pnode = emalloc(sizeof(*pnode));
340 	pnode->head = RESET;
341 	pnode->in_progress = RESET;
342 	pnode->fnode = fnode;
343 	pnode->next = head->next;
344 	pnode->last = head;
345 	head->next = pnode;
346 	if (pnode->next != NULL)
347 		pnode->next->last = pnode;
348 
349 	f_pnode = emalloc(sizeof(*f_pnode));
350 	f_pnode->pnode = pnode;
351 	f_pnode->next = fnode->prov_list;
352 	fnode->prov_list = f_pnode;
353 }
354 
355 /*
356  * put the BEFORE: lines to a list and handle them later.
357  */
358 static void
359 add_before(filenode *fnode, char *s)
360 {
361 	strnodelist *bf_ent;
362 
363 	bf_ent = emalloc(sizeof *bf_ent + strlen(s));
364 	bf_ent->node = fnode;
365 	strcpy(bf_ent->s, s);
366 	bf_ent->next = bl_list;
367 	bl_list = bf_ent;
368 }
369 
370 /*
371  * add a key to a filenode.
372  */
373 static void
374 add_keyword(filenode *fnode, char *s)
375 {
376 
377 	strnode_add(&fnode->keyword_list, s, fnode);
378 }
379 
380 /*
381  * loop over the rest of a REQUIRE line, giving each word to
382  * add_require() to do the real work.
383  */
384 static void
385 parse_require(filenode *node, char *buffer)
386 {
387 	char *s;
388 
389 	while ((s = strsep(&buffer, " \t\n")) != NULL)
390 		if (*s != '\0')
391 			add_require(node, s);
392 }
393 
394 /*
395  * loop over the rest of a PROVIDE line, giving each word to
396  * add_provide() to do the real work.
397  */
398 static void
399 parse_provide(filenode *node, char *buffer)
400 {
401 	char *s;
402 
403 	while ((s = strsep(&buffer, " \t\n")) != NULL)
404 		if (*s != '\0')
405 			add_provide(node, s);
406 }
407 
408 /*
409  * loop over the rest of a BEFORE line, giving each word to
410  * add_before() to do the real work.
411  */
412 static void
413 parse_before(filenode *node, char *buffer)
414 {
415 	char *s;
416 
417 	while ((s = strsep(&buffer, " \t\n")) != NULL)
418 		if (*s != '\0')
419 			add_before(node, s);
420 }
421 
422 /*
423  * loop over the rest of a KEYWORD line, giving each word to
424  * add_keyword() to do the real work.
425  */
426 static void
427 parse_keywords(filenode *node, char *buffer)
428 {
429 	char *s;
430 
431 	while ((s = strsep(&buffer, " \t\n")) != NULL)
432 		if (*s != '\0')
433 			add_keyword(node, s);
434 }
435 
436 /*
437  * given a file name, create a filenode for it, read in lines looking
438  * for provision and requirement lines, building the graphs as needed.
439  */
440 static void
441 crunch_file(char *filename)
442 {
443 	FILE *fp;
444 	char *buf;
445 	int require_flag, provide_flag, before_flag, keywords_flag;
446 	enum { BEFORE_PARSING, PARSING, PARSING_DONE } state;
447 	filenode *node;
448 	char delims[3] = { '\\', '\\', '\0' };
449 	struct stat st;
450 
451 	if ((fp = fopen(filename, "r")) == NULL) {
452 		warn("could not open %s", filename);
453 		return;
454 	}
455 
456 	if (fstat(fileno(fp), &st) == -1) {
457 		warn("could not stat %s", filename);
458 		fclose(fp);
459 		return;
460 	}
461 
462 	if (!S_ISREG(st.st_mode)) {
463 #if 0
464 		warnx("%s is not a file", filename);
465 #endif
466 		fclose(fp);
467 		return;
468 	}
469 
470 	node = filenode_new(filename);
471 
472 	/*
473 	 * we don't care about length, line number, don't want # for comments,
474 	 * and have no flags.
475 	 */
476 	for (state = BEFORE_PARSING; state != PARSING_DONE &&
477 	    (buf = fparseln(fp, NULL, NULL, delims, 0)) != NULL; free(buf)) {
478 		require_flag = provide_flag = before_flag = keywords_flag = 0;
479 		if (strncmp(REQUIRE_STR, buf, REQUIRE_LEN) == 0)
480 			require_flag = REQUIRE_LEN;
481 		else if (strncmp(REQUIRES_STR, buf, REQUIRES_LEN) == 0)
482 			require_flag = REQUIRES_LEN;
483 		else if (strncmp(PROVIDE_STR, buf, PROVIDE_LEN) == 0)
484 			provide_flag = PROVIDE_LEN;
485 		else if (strncmp(PROVIDES_STR, buf, PROVIDES_LEN) == 0)
486 			provide_flag = PROVIDES_LEN;
487 		else if (strncmp(BEFORE_STR, buf, BEFORE_LEN) == 0)
488 			before_flag = BEFORE_LEN;
489 		else if (strncmp(KEYWORD_STR, buf, KEYWORD_LEN) == 0)
490 			keywords_flag = KEYWORD_LEN;
491 		else if (strncmp(KEYWORDS_STR, buf, KEYWORDS_LEN) == 0)
492 			keywords_flag = KEYWORDS_LEN;
493 		else {
494 			if (state == PARSING)
495 				state = PARSING_DONE;
496 			continue;
497 		}
498 
499 		state = PARSING;
500 		if (require_flag)
501 			parse_require(node, buf + require_flag);
502 		else if (provide_flag)
503 			parse_provide(node, buf + provide_flag);
504 		else if (before_flag)
505 			parse_before(node, buf + before_flag);
506 		else if (keywords_flag)
507 			parse_keywords(node, buf + keywords_flag);
508 	}
509 	fclose(fp);
510 }
511 
512 static Hash_Entry *
513 make_fake_provision(filenode *node)
514 {
515 	Hash_Entry *entry;
516 	f_provnode *f_pnode;
517 	provnode *head, *pnode;
518 	static	int i = 0;
519 	int	new;
520 	char buffer[30];
521 
522 	do {
523 		snprintf(buffer, sizeof buffer, "fake_prov_%08d", i++);
524 		entry = Hash_CreateEntry(provide_hash, buffer, &new);
525 	} while (new == 0);
526 	head = emalloc(sizeof(*head));
527 	head->head = SET;
528 	head->in_progress = RESET;
529 	head->fnode = NULL;
530 	head->last = head->next = NULL;
531 	Hash_SetValue(entry, head);
532 
533 	pnode = emalloc(sizeof(*pnode));
534 	pnode->head = RESET;
535 	pnode->in_progress = RESET;
536 	pnode->fnode = node;
537 	pnode->next = head->next;
538 	pnode->last = head;
539 	head->next = pnode;
540 	if (pnode->next != NULL)
541 		pnode->next->last = pnode;
542 
543 	f_pnode = emalloc(sizeof(*f_pnode));
544 	f_pnode->pnode = pnode;
545 	f_pnode->next = node->prov_list;
546 	node->prov_list = f_pnode;
547 
548 	return (entry);
549 }
550 
551 /*
552  * go through the BEFORE list, inserting requirements into the graph(s)
553  * as required.  in the before list, for each entry B, we have a file F
554  * and a string S.  we create a "fake" provision (P) that F provides.
555  * for each entry in the provision list for S, add a requirement to
556  * that provisions filenode for P.
557  */
558 static void
559 insert_before(void)
560 {
561 	Hash_Entry *entry, *fake_prov_entry;
562 	provnode *pnode;
563 	f_reqnode *rnode;
564 	strnodelist *bl;
565 	int new;
566 
567 	while (bl_list != NULL) {
568 		bl = bl_list->next;
569 
570 		fake_prov_entry = make_fake_provision(bl_list->node);
571 
572 		entry = Hash_CreateEntry(provide_hash, bl_list->s, &new);
573 		if (new == 1)
574 			warnx("file `%s' is before unknown provision `%s'", bl_list->node->filename, bl_list->s);
575 
576 		for (pnode = Hash_GetValue(entry); pnode; pnode = pnode->next) {
577 			if (pnode->head)
578 				continue;
579 
580 			rnode = emalloc(sizeof(*rnode));
581 			rnode->entry = fake_prov_entry;
582 			rnode->next = pnode->fnode->req_list;
583 			pnode->fnode->req_list = rnode;
584 		}
585 
586 		free(bl_list);
587 		bl_list = bl;
588 	}
589 }
590 
591 /*
592  * loop over all the files calling crunch_file() on them to do the
593  * real work.  after we have built all the nodes, insert the BEFORE:
594  * lines into graph(s).
595  */
596 static void
597 crunch_all_files(void)
598 {
599 	int i;
600 
601 	for (i = 0; i < file_count; i++)
602 		crunch_file(file_list[i]);
603 	insert_before();
604 }
605 
606 /*
607  * below are the functions that traverse the graphs we have built
608  * finding out the desired ordering, printing each file in turn.
609  * if missing requirements, or cyclic graphs are detected, a
610  * warning will be issued, and we will continue on..
611  */
612 
613 /*
614  * given a requirement node (in a filename) we attempt to satisfy it.
615  * we do some sanity checking first, to ensure that we have providers,
616  * aren't already satisfied and aren't already being satisfied (ie,
617  * cyclic).  if we pass all this, we loop over the provision list
618  * calling do_file() (enter recursion) for each filenode in this
619  * provision.
620  */
621 static void
622 satisfy_req(f_reqnode *rnode, char *filename)
623 {
624 	Hash_Entry *entry;
625 	provnode *head;
626 
627 	entry = rnode->entry;
628 	head = Hash_GetValue(entry);
629 
630 	if (head == NULL) {
631 		warnx("requirement `%s' in file `%s' has no providers.",
632 		    Hash_GetKey(entry), filename);
633 		exit_code = 1;
634 		return;
635 	}
636 
637 	/* return if the requirement is already satisfied. */
638 	if (head->next == NULL)
639 		return;
640 
641 	/*
642 	 * if list is marked as in progress,
643 	 *	print that there is a circular dependency on it and abort
644 	 */
645 	if (head->in_progress == SET) {
646 		warnx("Circular dependency on provision `%s' in file `%s'.",
647 		    Hash_GetKey(entry), filename);
648 		exit_code = 1;
649 		return;
650 	}
651 
652 	head->in_progress = SET;
653 
654 	/*
655 	 * while provision_list is not empty
656 	 *	do_file(first_member_of(provision_list));
657 	 */
658 	while (head->next != NULL)
659 		do_file(head->next->fnode);
660 }
661 
662 static int
663 skip_ok(filenode *fnode)
664 {
665 	strnodelist *s;
666 	strnodelist *k;
667 
668 	for (s = skip_list; s; s = s->next)
669 		for (k = fnode->keyword_list; k; k = k->next)
670 			if (strcmp(k->s, s->s) == 0)
671 				return (0);
672 
673 	return (1);
674 }
675 
676 static int
677 keep_ok(filenode *fnode)
678 {
679 	strnodelist *s;
680 	strnodelist *k;
681 
682 	for (s = keep_list; s; s = s->next)
683 		for (k = fnode->keyword_list; k; k = k->next)
684 			if (strcmp(k->s, s->s) == 0)
685 				return (1);
686 
687 	/* an empty keep_list means every one */
688 	return (!keep_list);
689 }
690 
691 /*
692  * given a filenode, we ensure we are not a cyclic graph.  if this
693  * is ok, we loop over the filenodes requirements, calling satisfy_req()
694  * for each of them.. once we have done this, remove this filenode
695  * from each provision table, as we are now done.
696  *
697  * NOTE: do_file() is called recursively from several places and cannot
698  * safely free() anything related to items that may be recursed on.
699  * Circular dependencies will cause problems if we do.
700  */
701 static void
702 do_file(filenode *fnode)
703 {
704 	f_reqnode *r;
705 	f_provnode *p, *p_tmp;
706 	provnode *pnode;
707 	int was_set;
708 
709 	DPRINTF((stderr, "do_file on %s.\n", fnode->filename));
710 
711 	/*
712 	 * if fnode is marked as in progress,
713 	 *	 print that fnode; is circularly depended upon and abort.
714 	 */
715 	if (fnode->in_progress == SET) {
716 		warnx("Circular dependency on file `%s'.",
717 			fnode->filename);
718 		was_set = exit_code = 1;
719 	} else
720 		was_set = 0;
721 
722 	/* mark fnode */
723 	fnode->in_progress = SET;
724 
725 	/*
726 	 * for each requirement of fnode -> r
727 	 *	satisfy_req(r, filename)
728 	 */
729 	r = fnode->req_list;
730 	while (r != NULL) {
731 		satisfy_req(r, fnode->filename);
732 		r = r->next;
733 	}
734 	fnode->req_list = NULL;
735 
736 	/*
737 	 * for each provision of fnode -> p
738 	 *	remove fnode from provision list for p in hash table
739 	 */
740 	p = fnode->prov_list;
741 	while (p != NULL) {
742 		p_tmp = p;
743 		pnode = p->pnode;
744 		if (pnode->next != NULL) {
745 			pnode->next->last = pnode->last;
746 		}
747 		if (pnode->last != NULL) {
748 			pnode->last->next = pnode->next;
749 		}
750 		free(pnode);
751 		p = p->next;
752 		free(p_tmp);
753 	}
754 	fnode->prov_list = NULL;
755 
756 	/* do_it(fnode) */
757 	DPRINTF((stderr, "next do: "));
758 
759 	/* if we were already in progress, don't print again */
760 	if (was_set == 0 && skip_ok(fnode) && keep_ok(fnode))
761 		printf("%s\n", fnode->filename);
762 
763 	if (fnode->next != NULL) {
764 		fnode->next->last = fnode->last;
765 	}
766 	if (fnode->last != NULL) {
767 		fnode->last->next = fnode->next;
768 	}
769 
770 	DPRINTF((stderr, "nuking %s\n", fnode->filename));
771 #if 0
772 	if (was_set == 0) {
773    		free(fnode->filename);
774    		free(fnode);
775 	}
776 #endif
777 }
778 
779 static void
780 generate_ordering(void)
781 {
782 
783 	/*
784 	 * while there remain undone files{f},
785 	 *	pick an arbitrary f, and do_file(f)
786 	 * Note that the first file in the file list is perfectly
787 	 * arbitrary, and easy to find, so we use that.
788 	 */
789 
790 	/*
791 	 * N.B.: the file nodes "self delete" after they execute, so
792 	 * after each iteration of the loop, the head will be pointing
793 	 * to something totally different. The loop ends up being
794 	 * executed only once for every strongly connected set of
795 	 * nodes.
796 	 */
797 	while (fn_head->next != NULL) {
798 		DPRINTF((stderr, "generate on %s\n", fn_head->next->filename));
799 		do_file(fn_head->next);
800 	}
801 }
802