xref: /netbsd-src/external/bsd/nvi/dist/ex/ex_cscope.c (revision aceb213538ec08a74028e213127af18aa17bf1cf)
1 /*	$NetBSD: ex_cscope.c,v 1.4 2013/11/27 18:11:00 christos Exp $ */
2 /*-
3  * Copyright (c) 1994, 1996
4  *	Rob Mayoff.  All rights reserved.
5  * Copyright (c) 1996
6  *	Keith Bostic.  All rights reserved.
7  *
8  * See the LICENSE file for redistribution information.
9  */
10 
11 #include "config.h"
12 
13 #ifndef lint
14 static const char sccsid[] = "Id: ex_cscope.c,v 10.21 2003/11/05 17:11:54 skimo Exp  (Berkeley) Date: 2003/11/05 17:11:54 ";
15 #endif /* not lint */
16 
17 #include <sys/param.h>
18 #include <sys/types.h>		/* XXX: param.h may not have included types.h */
19 #include <sys/queue.h>
20 #include <sys/stat.h>
21 #include <sys/time.h>
22 #include <sys/wait.h>
23 
24 #include <bitstring.h>
25 #include <ctype.h>
26 #include <errno.h>
27 #include <fcntl.h>
28 #include <limits.h>
29 #include <stddef.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <termios.h>
34 #include <unistd.h>
35 
36 #include "../common/common.h"
37 #include "pathnames.h"
38 #include "tag.h"
39 
40 #define	CSCOPE_DBFILE		"cscope.out"
41 #define	CSCOPE_PATHS		"cscope.tpath"
42 
43 /*
44  * 0name	find all uses of name
45  * 1name	find definition of name
46  * 2name	find all function calls made from name
47  * 3name	find callers of name
48  * 4string	find text string (cscope 12.9)
49  * 4name	find assignments to name (cscope 13.3)
50  * 5pattern	change pattern -- NOT USED
51  * 6pattern	find pattern
52  * 7name	find files with name as substring
53  * 8name	find files #including name
54  */
55 #define	FINDHELP "\
56 find c|d|e|f|g|i|s|t buffer|pattern\n\
57       c: find callers of name\n\
58       d: find all function calls made from name\n\
59       e: find pattern\n\
60       f: find files with name as substring\n\
61       g: find definition of name\n\
62       i: find files #including name\n\
63       s: find all uses of name\n\
64       t: find assignments to name"
65 
66 static int cscope_add __P((SCR *, EXCMD *, const CHAR_T *));
67 static int cscope_find __P((SCR *, EXCMD*, const CHAR_T *));
68 static int cscope_help __P((SCR *, EXCMD *, const CHAR_T *));
69 static int cscope_kill __P((SCR *, EXCMD *, const CHAR_T *));
70 static int cscope_reset __P((SCR *, EXCMD *, const CHAR_T *));
71 
72 typedef struct _cc {
73 	const char	 *name;
74 	int	(*function) __P((SCR *, EXCMD *, const CHAR_T *));
75 	const char	 *help_msg;
76 	const char	 *usage_msg;
77 } CC;
78 
79 static CC const cscope_cmds[] = {
80 	{ "add",   cscope_add,
81 	  "Add a new cscope database", "add file | directory" },
82 	{ "find",  cscope_find,
83 	  "Query the databases for a pattern", FINDHELP },
84 	{ "help",  cscope_help,
85 	  "Show help for cscope commands", "help [command]" },
86 	{ "kill",  cscope_kill,
87 	  "Kill a cscope connection", "kill number" },
88 	{ "reset", cscope_reset,
89 	  "Discard all current cscope connections", "reset" },
90 	{ NULL, NULL, NULL, NULL }
91 };
92 
93 static TAGQ	*create_cs_cmd __P((SCR *, const char *, size_t *));
94 static int	 csc_help __P((SCR *, const char *));
95 static void	 csc_file __P((SCR *,
96 		    CSC *, char *, char **, size_t *, int *));
97 static int	 get_paths __P((SCR *, CSC *));
98 static CC const	*lookup_ccmd __P((const char *));
99 static int	 parse __P((SCR *, CSC *, TAGQ *, int *));
100 static int	 read_prompt __P((SCR *, CSC *));
101 static int	 run_cscope __P((SCR *, CSC *, const char *));
102 static int	 start_cscopes __P((SCR *, EXCMD *));
103 static int	 terminate __P((SCR *, CSC *, int));
104 
105 /*
106  * ex_cscope --
107  *	Perform an ex cscope.
108  *
109  * PUBLIC: int ex_cscope __P((SCR *, EXCMD *));
110  */
111 int
112 ex_cscope(SCR *sp, EXCMD *cmdp)
113 {
114 	CC const *ccp;
115 	EX_PRIVATE *exp;
116 	int i;
117 	CHAR_T *cmd;
118 	CHAR_T *p;
119 	const char *np;
120 	size_t nlen;
121 
122 	/* Initialize the default cscope directories. */
123 	exp = EXP(sp);
124 	if (!F_ISSET(exp, EXP_CSCINIT) && start_cscopes(sp, cmdp))
125 		return (1);
126 	F_SET(exp, EXP_CSCINIT);
127 
128 	/* Skip leading whitespace. */
129 	for (p = cmdp->argv[0]->bp, i = cmdp->argv[0]->len; i > 0; --i, ++p)
130 		if (!ISBLANK((UCHAR_T)*p))
131 			break;
132 	if (i == 0)
133 		goto usage;
134 
135 	/* Skip the command to any arguments. */
136 	for (cmd = p; i > 0; --i, ++p)
137 		if (ISBLANK((UCHAR_T)*p))
138 			break;
139 	if (*p != '\0') {
140 		*p++ = '\0';
141 		for (; *p && ISBLANK((UCHAR_T)*p); ++p);
142 	}
143 
144 	INT2CHAR(sp, cmd, STRLEN(cmd) + 1, np, nlen);
145 	if ((ccp = lookup_ccmd(np)) == NULL) {
146 usage:		msgq(sp, M_ERR, "309|Use \"cscope help\" for help");
147 		return (1);
148 	}
149 
150 	/* Call the underlying function. */
151 	return (ccp->function(sp, cmdp, p));
152 }
153 
154 /*
155  * start_cscopes --
156  *	Initialize the cscope package.
157  */
158 static int
159 start_cscopes(SCR *sp, EXCMD *cmdp)
160 {
161 	size_t blen, len;
162 	char *bp, *cscopes, *p, *t;
163 	const CHAR_T *wp;
164 	size_t wlen;
165 
166 	/*
167 	 * EXTENSION #1:
168 	 *
169 	 * If the CSCOPE_DIRS environment variable is set, we treat it as a
170 	 * list of cscope directories that we're using, similar to the tags
171 	 * edit option.
172 	 *
173 	 * XXX
174 	 * This should probably be an edit option, although that implies that
175 	 * we start/stop cscope processes periodically, instead of once when
176 	 * the editor starts.
177 	 */
178 	if ((cscopes = getenv("CSCOPE_DIRS")) == NULL)
179 		return (0);
180 	len = strlen(cscopes);
181 	GET_SPACE_RETC(sp, bp, blen, len);
182 	memcpy(bp, cscopes, len + 1);
183 
184 	for (cscopes = t = bp; (p = strsep(&t, "\t :")) != NULL;)
185 		if (*p != '\0') {
186 			CHAR2INT(sp, p, strlen(p) + 1, wp, wlen);
187 			(void)cscope_add(sp, cmdp, wp);
188 		}
189 
190 	FREE_SPACE(sp, bp, blen);
191 	return (0);
192 }
193 
194 /*
195  * cscope_add --
196  *	The cscope add command.
197  */
198 static int
199 cscope_add(SCR *sp, EXCMD *cmdp, const CHAR_T *dname)
200 {
201 	struct stat sb;
202 	EX_PRIVATE *exp;
203 	CSC *csc;
204 	size_t len;
205 	int cur_argc;
206 	const char *dbname;
207 	char path[MAXPATHLEN];
208 	const char *np;
209 	char *npp;
210 	size_t nlen;
211 
212 	exp = EXP(sp);
213 
214 	/*
215 	 *  0 additional args: usage.
216 	 *  1 additional args: matched a file.
217 	 * >1 additional args: object, too many args.
218 	 */
219 	cur_argc = cmdp->argc;
220 	if (argv_exp2(sp, cmdp, dname, STRLEN(dname))) {
221 		return (1);
222 	}
223 	if (cmdp->argc == cur_argc) {
224 		(void)csc_help(sp, "add");
225 		return (1);
226 	}
227 	if (cmdp->argc == cur_argc + 1)
228 		dname = cmdp->argv[cur_argc]->bp;
229 	else {
230 		ex_emsg(sp, np, EXM_FILECOUNT);
231 		return (1);
232 	}
233 
234 	INT2CHAR(sp, dname, STRLEN(dname)+1, np, nlen);
235 
236 	/*
237 	 * The user can specify a specific file (so they can have multiple
238 	 * Cscope databases in a single directory) or a directory.  If the
239 	 * file doesn't exist, we're done.  If it's a directory, append the
240 	 * standard database file name and try again.  Store the directory
241 	 * name regardless so that we can use it as a base for searches.
242 	 */
243 	if (stat(np, &sb)) {
244 		msgq(sp, M_SYSERR, "%s", np);
245 		return (1);
246 	}
247 	if (S_ISDIR(sb.st_mode)) {
248 		(void)snprintf(path, sizeof(path),
249 		    "%s/%s", np, CSCOPE_DBFILE);
250 		if (stat(path, &sb)) {
251 			msgq(sp, M_SYSERR, "%s", path);
252 			return (1);
253 		}
254 		dbname = CSCOPE_DBFILE;
255 	} else if ((npp = strrchr(np, '/')) != NULL) {
256 		*npp = '\0';
257 		dbname = npp + 1;
258 	} else {
259 		dbname = np;
260 		np = ".";
261 	}
262 
263 	/* Allocate a cscope connection structure and initialize its fields. */
264 	len = strlen(np);
265 	CALLOC_RET(sp, csc, CSC *, 1, sizeof(CSC) + len);
266 	csc->dname = csc->buf;
267 	csc->dlen = len;
268 	memcpy(csc->dname, np, len);
269 	csc->mtime = sb.st_mtime;
270 
271 	/* Get the search paths for the cscope. */
272 	if (get_paths(sp, csc))
273 		goto err;
274 
275 	/* Start the cscope process. */
276 	if (run_cscope(sp, csc, dbname))
277 		goto err;
278 
279 	/*
280 	 * Add the cscope connection to the screen's list.  From now on,
281 	 * on error, we have to call terminate, which expects the csc to
282 	 * be on the chain.
283 	 */
284 	LIST_INSERT_HEAD(&exp->cscq, csc, q);
285 
286 	/* Read the initial prompt from the cscope to make sure it's okay. */
287 	return read_prompt(sp, csc);
288 
289 err:	free(csc);
290 	return (1);
291 }
292 
293 /*
294  * get_paths --
295  *	Get the directories to search for the files associated with this
296  *	cscope database.
297  */
298 static int
299 get_paths(SCR *sp, CSC *csc)
300 {
301 	struct stat sb;
302 	int fd, nentries;
303 	size_t len;
304 	char *p, **pathp, buf[MAXPATHLEN * 2];
305 
306 	/*
307 	 * EXTENSION #2:
308 	 *
309 	 * If there's a cscope directory with a file named CSCOPE_PATHS, it
310 	 * contains a colon-separated list of paths in which to search for
311 	 * files returned by cscope.
312 	 *
313 	 * XXX
314 	 * These paths are absolute paths, and not relative to the cscope
315 	 * directory.  To fix this, rewrite the each path using the cscope
316 	 * directory as a prefix.
317 	 */
318 	(void)snprintf(buf, sizeof(buf), "%s/%s", csc->dname, CSCOPE_PATHS);
319 	if (stat(buf, &sb) == 0) {
320 		/* Read in the CSCOPE_PATHS file. */
321 		len = sb.st_size;
322 		MALLOC_RET(sp, csc->pbuf, char *, len + 1);
323 		if ((fd = open(buf, O_RDONLY, 0)) < 0 ||
324 		    (size_t)read(fd, csc->pbuf, len) != len) {
325 			 msgq_str(sp, M_SYSERR, buf, "%s");
326 			 if (fd >= 0)
327 				(void)close(fd);
328 			 return (1);
329 		}
330 		(void)close(fd);
331 		csc->pbuf[len] = '\0';
332 
333 		/* Count up the entries. */
334 		for (nentries = 0, p = csc->pbuf; *p != '\0'; ++p)
335 			if (p[0] == ':' && p[1] != '\0')
336 				++nentries;
337 
338 		/* Build an array of pointers to the paths. */
339 		CALLOC_GOTO(sp,
340 		    csc->paths, char **, nentries + 1, sizeof(char **));
341 		for (pathp = csc->paths, p = strtok(csc->pbuf, ":");
342 		    p != NULL; p = strtok(NULL, ":"))
343 			*pathp++ = p;
344 		return (0);
345 	}
346 
347 	/*
348 	 * If the CSCOPE_PATHS file doesn't exist, we look for files
349 	 * relative to the cscope directory.
350 	 */
351 	if ((csc->pbuf = strdup(csc->dname)) == NULL) {
352 		msgq(sp, M_SYSERR, NULL);
353 		return (1);
354 	}
355 	CALLOC_GOTO(sp, csc->paths, char **, 2, sizeof(char *));
356 	csc->paths[0] = csc->pbuf;
357 	return (0);
358 
359 alloc_err:
360 	if (csc->pbuf != NULL) {
361 		free(csc->pbuf);
362 		csc->pbuf = NULL;
363 	}
364 	return (1);
365 }
366 
367 /*
368  * run_cscope --
369  *	Fork off the cscope process.
370  */
371 static int
372 run_cscope(SCR *sp, CSC *csc, const char *dbname)
373 {
374 	int to_cs[2], from_cs[2];
375 	char cmd[MAXPATHLEN * 2];
376 
377 	/*
378 	 * Cscope reads from to_cs[0] and writes to from_cs[1]; vi reads from
379 	 * from_cs[0] and writes to to_cs[1].
380 	 */
381 	to_cs[0] = to_cs[1] = from_cs[0] = from_cs[1] = -1;
382 	if (pipe(to_cs) < 0 || pipe(from_cs) < 0) {
383 		msgq(sp, M_SYSERR, "pipe");
384 		goto err;
385 	}
386 	switch (csc->pid = vfork()) {
387 	case -1:
388 		msgq(sp, M_SYSERR, "vfork");
389 err:		if (to_cs[0] != -1)
390 			(void)close(to_cs[0]);
391 		if (to_cs[1] != -1)
392 			(void)close(to_cs[1]);
393 		if (from_cs[0] != -1)
394 			(void)close(from_cs[0]);
395 		if (from_cs[1] != -1)
396 			(void)close(from_cs[1]);
397 		return (1);
398 	case 0:				/* child: run cscope. */
399 		(void)dup2(to_cs[0], STDIN_FILENO);
400 		(void)dup2(from_cs[1], STDOUT_FILENO);
401 		(void)dup2(from_cs[1], STDERR_FILENO);
402 
403 		/* Close unused file descriptors. */
404 		(void)close(to_cs[1]);
405 		(void)close(from_cs[0]);
406 
407 		/* Run the cscope command. */
408 #define	CSCOPE_CMD_FMT		"cd '%s' && exec cscope -dl -f %s"
409 		(void)snprintf(cmd, sizeof(cmd),
410 		    CSCOPE_CMD_FMT, csc->dname, dbname);
411 		(void)execl(_PATH_BSHELL, "sh", "-c", cmd, (char *)NULL);
412 		msgq_str(sp, M_SYSERR, cmd, "execl: %s");
413 		_exit (127);
414 		/* NOTREACHED */
415 	default:			/* parent. */
416 		/* Close unused file descriptors. */
417 		(void)close(to_cs[0]);
418 		(void)close(from_cs[1]);
419 
420 		/*
421 		 * Save the file descriptors for later duplication, and
422 		 * reopen as streams.
423 		 */
424 		csc->to_fd = to_cs[1];
425 		csc->to_fp = fdopen(to_cs[1], "w");
426 		csc->from_fd = from_cs[0];
427 		csc->from_fp = fdopen(from_cs[0], "r");
428 		break;
429 	}
430 	return (0);
431 }
432 
433 /*
434  * cscope_find --
435  *	The cscope find command.
436  */
437 static int
438 cscope_find(SCR *sp, EXCMD *cmdp, const CHAR_T *pattern)
439 {
440 	CSC *csc, *csc_next;
441 	EX_PRIVATE *exp;
442 	FREF *frp;
443 	TAGQ *rtqp, *tqp;
444 	TAG *rtp;
445 	db_recno_t lno;
446 	size_t cno, search;
447 	int force, istmp, matches;
448 	const char *np = NULL;
449 	size_t nlen;
450 
451 	exp = EXP(sp);
452 
453 	/* Check for connections. */
454 	if (LIST_EMPTY(&exp->cscq)) {
455 		msgq(sp, M_ERR, "310|No cscope connections running");
456 		return (1);
457 	}
458 
459 	/*
460 	 * Allocate all necessary memory before doing anything hard.  If the
461 	 * tags stack is empty, we'll need the `local context' TAGQ structure
462 	 * later.
463 	 */
464 	rtp = NULL;
465 	rtqp = NULL;
466 	if (TAILQ_EMPTY(&exp->tq)) {
467 		/* Initialize the `local context' tag queue structure. */
468 		CALLOC_GOTO(sp, rtqp, TAGQ *, 1, sizeof(TAGQ));
469 		TAILQ_INIT(&rtqp->tagq);
470 
471 		/* Initialize and link in its tag structure. */
472 		CALLOC_GOTO(sp, rtp, TAG *, 1, sizeof(TAG));
473 		TAILQ_INSERT_HEAD(&rtqp->tagq, rtp, q);
474 		rtqp->current = rtp;
475 	}
476 
477 	/* Create the cscope command. */
478 	INT2CHAR(sp, pattern, STRLEN(pattern) + 1, np, nlen);
479 	np = strdup(np);
480 	if ((tqp = create_cs_cmd(sp, np, &search)) == NULL)
481 		goto err;
482 
483 	/*
484 	 * Stick the current context in a convenient place, we'll lose it
485 	 * when we switch files.
486 	 */
487 	frp = sp->frp;
488 	lno = sp->lno;
489 	cno = sp->cno;
490 	istmp = F_ISSET(sp->frp, FR_TMPFILE) && !F_ISSET(cmdp, E_NEWSCREEN);
491 
492 	/* Search all open connections for a match. */
493 	matches = 0;
494 	LIST_FOREACH_SAFE(csc, &exp->cscq, q, csc_next) {
495 		/*
496 		 * Send the command to the cscope program.  (We skip the
497 		 * first two bytes of the command, because we stored the
498 		 * search cscope command character and a leading space
499 		 * there.)
500 		 */
501 		(void)fprintf(csc->to_fp, "%zu%s\n", search, tqp->tag + 2);
502 		(void)fflush(csc->to_fp);
503 
504 		/* Read the output. */
505 		if (parse(sp, csc, tqp, &matches)) {
506 			free(rtqp);
507 			tagq_free(sp, tqp);
508 			return (1);
509 		}
510 	}
511 
512 	if (matches == 0) {
513 		free(rtqp);
514 		msgq(sp, M_INFO, "278|No matches for query");
515 		return (0);
516 	}
517 
518 	tqp->current = TAILQ_FIRST(&tqp->tagq);
519 
520 	/* Try to switch to the first tag. */
521 	force = FL_ISSET(cmdp->iflags, E_C_FORCE);
522 	if (F_ISSET(cmdp, E_NEWSCREEN)) {
523 		if (ex_tag_Nswitch(sp, tqp->current, force))
524 			goto err;
525 
526 		/* Everything else gets done in the new screen. */
527 		sp = sp->nextdisp;
528 		exp = EXP(sp);
529 	} else
530 		if (ex_tag_nswitch(sp, tqp->current, force))
531 			goto err;
532 
533 	/*
534 	 * If this is the first tag, put a `current location' queue entry
535 	 * in place, so we can pop all the way back to the current mark.
536 	 * Note, it doesn't point to much of anything, it's a placeholder.
537 	 */
538 	if (TAILQ_EMPTY(&exp->tq)) {
539 		TAILQ_INSERT_HEAD(&exp->tq, rtqp, q);
540 	} else {
541 		free(rtqp);
542 		rtqp = TAILQ_FIRST(&exp->tq);
543 	}
544 
545 	/* Link the current TAGQ structure into place. */
546 	TAILQ_INSERT_HEAD(&exp->tq, tqp, q);
547 
548 	(void)cscope_search(sp, tqp, tqp->current);
549 
550 	/*
551 	 * Move the current context from the temporary save area into the
552 	 * right structure.
553 	 *
554 	 * If we were in a temporary file, we don't have a context to which
555 	 * we can return, so just make it be the same as what we're moving
556 	 * to.  It will be a little odd that ^T doesn't change anything, but
557 	 * I don't think it's a big deal.
558 	 */
559 	if (istmp) {
560 		rtqp->current->frp = sp->frp;
561 		rtqp->current->lno = sp->lno;
562 		rtqp->current->cno = sp->cno;
563 	} else {
564 		rtqp->current->frp = frp;
565 		rtqp->current->lno = lno;
566 		rtqp->current->cno = cno;
567 	}
568 
569 	return (0);
570 
571 err:
572 alloc_err:
573 	free(rtqp);
574 	free(rtp);
575 	free(__UNCONST(np));
576 	return (1);
577 }
578 
579 /*
580  * create_cs_cmd --
581  *	Build a cscope command, creating and initializing the base TAGQ.
582  */
583 static TAGQ *
584 create_cs_cmd(SCR *sp, const char *pattern, size_t *searchp)
585 {
586 	CB *cbp;
587 	TAGQ *tqp;
588 	size_t tlen;
589 	const char *p;
590 
591 	/*
592 	 * Cscope supports a "change pattern" command which we never use,
593 	 * cscope command 5.  Set CSCOPE_QUERIES[5] to " " since the user
594 	 * can't pass " " as the first character of pattern.  That way the
595 	 * user can't ask for pattern 5 so we don't need any special-case
596 	 * code.
597 	 */
598 #define	CSCOPE_QUERIES		"sgdct efi"
599 
600 	if (pattern == NULL)
601 		goto usage;
602 
603 	/* Skip leading blanks, check for command character. */
604 	for (; isblank((unsigned char)pattern[0]); ++pattern);
605 	if (pattern[0] == '\0' || !isblank((unsigned char)pattern[1]))
606 		goto usage;
607 	for (*searchp = 0, p = CSCOPE_QUERIES;
608 	    *p != '\0' && *p != pattern[0]; ++*searchp, ++p);
609 	if (*p == '\0') {
610 		msgq(sp, M_ERR,
611 		    "311|%s: unknown search type: use one of %s",
612 		    KEY_NAME(sp, pattern[0]), CSCOPE_QUERIES);
613 		return (NULL);
614 	}
615 
616 	/* Skip <blank> characters to the pattern. */
617 	for (p = pattern + 1; *p != '\0' && isblank((unsigned char)*p); ++p);
618 	if (*p == '\0') {
619 usage:		(void)csc_help(sp, "find");
620 		return (NULL);
621 	}
622 
623 	/* The user can specify the contents of a buffer as the pattern. */
624 	cbp = NULL;
625 	if (p[0] == '"' && p[1] != '\0' && p[2] == '\0')
626 		CBNAME(sp, cbp, p[1]);
627 	if (cbp != NULL) {
628 		TEXT *t = TAILQ_FIRST(&cbp->textq);
629 		INT2CHAR(sp, t->lb, t->len, p, tlen);
630 	} else
631 		tlen = strlen(p);
632 
633 	/* Allocate and initialize the TAGQ structure. */
634 	CALLOC(sp, tqp, TAGQ *, 1, sizeof(TAGQ) + tlen + 3);
635 	if (tqp == NULL)
636 		return (NULL);
637 	TAILQ_INIT(&tqp->tagq);
638 	tqp->tag = tqp->buf;
639 	tqp->tag[0] = pattern[0];
640 	tqp->tag[1] = ' ';
641 	tqp->tlen = tlen + 2;
642 	memcpy(tqp->tag + 2, p, tlen);
643 	tqp->tag[tlen + 2] = '\0';
644 	F_SET(tqp, TAG_CSCOPE);
645 
646 	return (tqp);
647 }
648 
649 /*
650  * parse --
651  *	Parse the cscope output.
652  */
653 static int
654 parse(SCR *sp, CSC *csc, TAGQ *tqp, int *matchesp)
655 {
656 	TAG *tp;
657 	db_recno_t slno = 0;
658 	size_t dlen, nlen = 0, slen = 0;
659 	int ch, i, isolder = 0, nlines;
660 	char *dname = NULL, *name = NULL, *search, *p, *t, dummy[2], buf[2048];
661 
662 	for (;;) {
663 		if (!fgets(buf, sizeof(buf), csc->from_fp))
664 			goto io_err;
665 
666 		/*
667 		 * If the database is out of date, or there's some other
668 		 * problem, cscope will output error messages before the
669 		 * number-of-lines output.  Display/discard any output
670 		 * that doesn't match what we want.
671 		 */
672 #define	CSCOPE_NLINES_FMT	"cscope: %d lines%1[\n]"
673 		if (sscanf(buf, CSCOPE_NLINES_FMT, &nlines, dummy) == 2)
674 			break;
675 		if ((p = strchr(buf, '\n')) != NULL)
676 			*p = '\0';
677 		msgq(sp, M_ERR, "%s: \"%s\"", csc->dname, buf);
678 	}
679 
680 	while (nlines--) {
681 		if (fgets(buf, sizeof(buf), csc->from_fp) == NULL)
682 			goto io_err;
683 
684 		/* If the line's too long for the buffer, discard it. */
685 		if ((p = strchr(buf, '\n')) == NULL) {
686 			while ((ch = getc(csc->from_fp)) != EOF && ch != '\n');
687 			continue;
688 		}
689 		*p = '\0';
690 
691 		/*
692 		 * The cscope output is in the following format:
693 		 *
694 		 *	<filename> <context> <line number> <pattern>
695 		 *
696 		 * Figure out how long everything is so we can allocate in one
697 		 * swell foop, but discard anything that looks wrong.
698 		 */
699 		for (p = buf, i = 0;
700 		    i < 3 && (t = strsep(&p, "\t ")) != NULL; ++i)
701 			switch (i) {
702 			case 0:			/* Filename. */
703 				name = t;
704 				nlen = strlen(name);
705 				break;
706 			case 1:			/* Context. */
707 				break;
708 			case 2:			/* Line number. */
709 				slno = (db_recno_t)atol(t);
710 				break;
711 			}
712 		if (i != 3 || p == NULL || t == NULL)
713 			continue;
714 
715 		/* The rest of the string is the search pattern. */
716 		search = p;
717 		slen = strlen(p);
718 
719 		/* Resolve the file name. */
720 		csc_file(sp, csc, name, &dname, &dlen, &isolder);
721 
722 		/*
723 		 * If the file is older than the cscope database, that is,
724 		 * the database was built since the file was last modified,
725 		 * or there wasn't a search string, use the line number.
726 		 */
727 		if (isolder || strcmp(search, "<unknown>") == 0) {
728 			search = NULL;
729 			slen = 0;
730 		}
731 
732 		/*
733 		 * Allocate and initialize a tag structure plus the variable
734 		 * length cscope information that follows it.
735 		 */
736 		CALLOC_RET(sp, tp,
737 		    TAG *, 1, sizeof(TAG) + dlen + 2 + nlen + 1 + slen + 1);
738 		tp->fname = (char *)tp->buf;
739 		if (dlen != 0) {
740 			memcpy(tp->fname, dname, dlen);
741 			tp->fname[dlen] = '/';
742 			++dlen;
743 		}
744 		memcpy(tp->fname + dlen, name, nlen + 1);
745 		tp->fnlen = dlen + nlen;
746 		tp->slno = slno;
747 		if (slen != 0) {
748 			tp->search = (CHAR_T*)(tp->fname + tp->fnlen + 1);
749 			MEMCPYW(tp->search, search, (tp->slen = slen) + 1);
750 		}
751 		TAILQ_INSERT_TAIL(&tqp->tagq, tp, q);
752 
753 		++*matchesp;
754 	}
755 
756 	return read_prompt(sp, csc);
757 
758 io_err:	if (feof(csc->from_fp))
759 		errno = EIO;
760 	msgq_str(sp, M_SYSERR, "%s", csc->dname);
761 	terminate(sp, csc, 0);
762 	return (1);
763 }
764 
765 /*
766  * csc_file --
767  *	Search for the right path to this file.
768  */
769 static void
770 csc_file(SCR *sp, CSC *csc, char *name, char **dirp, size_t *dlenp, int *isolderp)
771 {
772 	struct stat sb;
773 	char **pp, buf[MAXPATHLEN];
774 
775 	/*
776 	 * Check for the file in all of the listed paths.  If we don't
777 	 * find it, we simply return it unchanged.  We have to do this
778 	 * now, even though it's expensive, because if the user changes
779 	 * directories, we can't change our minds as to where the file
780 	 * lives.
781 	 */
782 	for (pp = csc->paths; *pp != NULL; ++pp) {
783 		(void)snprintf(buf, sizeof(buf), "%s/%s", *pp, name);
784 		if (stat(buf, &sb) == 0) {
785 			*dirp = *pp;
786 			*dlenp = strlen(*pp);
787 			*isolderp = sb.st_mtime < csc->mtime;
788 			return;
789 		}
790 	}
791 	*dlenp = 0;
792 }
793 
794 /*
795  * cscope_help --
796  *	The cscope help command.
797  */
798 static int
799 cscope_help(SCR *sp, EXCMD *cmdp, const CHAR_T *subcmd)
800 {
801 	const char *np;
802 	size_t nlen;
803 
804 	INT2CHAR(sp, subcmd, STRLEN(subcmd) + 1, np, nlen);
805 	return (csc_help(sp, np));
806 }
807 
808 /*
809  * csc_help --
810  *	Display help/usage messages.
811  */
812 static int
813 csc_help(SCR *sp, const char *cmd)
814 {
815 	CC const *ccp;
816 
817 	if (cmd != NULL && *cmd != '\0') {
818 		if ((ccp = lookup_ccmd(cmd)) == NULL) {
819 			ex_printf(sp,
820 			    "%s doesn't match any cscope command\n", cmd);
821 			return (1);
822 		} else {
823 			ex_printf(sp,
824 		          "Command: %s (%s)\n", ccp->name, ccp->help_msg);
825 			ex_printf(sp, "  Usage: %s\n", ccp->usage_msg);
826 			return (0);
827 		}
828 	}
829 
830 	ex_printf(sp, "cscope commands:\n");
831 	for (ccp = cscope_cmds; ccp->name != NULL; ++ccp)
832 		ex_printf(sp, "  %*s: %s\n", 5, ccp->name, ccp->help_msg);
833 	return (0);
834 }
835 
836 /*
837  * cscope_kill --
838  *	The cscope kill command.
839  */
840 static int
841 cscope_kill(SCR *sp, EXCMD *cmdp, const CHAR_T *cn)
842 {
843 	const char *np;
844 	size_t nlen;
845 
846 	INT2CHAR(sp, cn, STRLEN(cn) + 1, np, nlen);
847 	return (terminate(sp, NULL, atoi(np)));
848 }
849 
850 /*
851  * terminate --
852  *	Detach from a cscope process.
853  */
854 static int
855 terminate(SCR *sp, CSC *csc, int n)
856 {
857 	EX_PRIVATE *exp;
858 	int i, pstat;
859 
860 	exp = EXP(sp);
861 
862 	/*
863 	 * We either get a csc structure or a number.  If not provided a
864 	 * csc structure, find the right one.
865 	 */
866 	if (csc == NULL) {
867 		if (n < 1)
868 			goto badno;
869 		i = 1;
870 		LIST_FOREACH(csc, &exp->cscq, q)
871 			if (i++ == n)
872 				break;
873 		if (csc == NULL) {
874 badno:			msgq(sp, M_ERR, "312|%d: no such cscope session", n);
875 			return (1);
876 		}
877 	}
878 
879 	/*
880 	 * XXX
881 	 * Theoretically, we have the only file descriptors to the process,
882 	 * so closing them should let it exit gracefully, deleting temporary
883 	 * files, etc.  The original vi cscope integration sent the cscope
884 	 * connection a SIGTERM signal, so I'm not sure if closing the file
885 	 * descriptors is sufficient.
886 	 */
887 	if (csc->from_fp != NULL)
888 		(void)fclose(csc->from_fp);
889 	if (csc->to_fp != NULL)
890 		(void)fclose(csc->to_fp);
891 	(void)waitpid(csc->pid, &pstat, 0);
892 
893 	/* Discard cscope connection information. */
894 	LIST_REMOVE(csc, q);
895 	if (csc->pbuf != NULL)
896 		free(csc->pbuf);
897 	if (csc->paths != NULL)
898 		free(csc->paths);
899 	free(csc);
900 	return (0);
901 }
902 
903 /*
904  * cscope_reset --
905  *	The cscope reset command.
906  */
907 static int
908 cscope_reset(SCR *sp, EXCMD *cmdp, const CHAR_T *notusedp)
909 {
910 	EX_PRIVATE *exp;
911 
912 	for (exp = EXP(sp); !LIST_EMPTY(&exp->cscq);) {
913 		static CHAR_T one[] = {'1', 0};
914 		if (cscope_kill(sp, cmdp, one))
915 			return (1);
916 	}
917 	return (0);
918 }
919 
920 /*
921  * cscope_display --
922  *	Display current connections.
923  *
924  * PUBLIC: int cscope_display __P((SCR *));
925  */
926 int
927 cscope_display(SCR *sp)
928 {
929 	EX_PRIVATE *exp;
930 	CSC *csc;
931 	int i;
932 
933 	exp = EXP(sp);
934 	if (LIST_EMPTY(&exp->cscq)) {
935 		ex_printf(sp, "No cscope connections.\n");
936 		return (0);
937 	}
938 	i = 1;
939 	LIST_FOREACH(csc, &exp->cscq, q)
940 		ex_printf(sp,
941 		    "%2d %s (process %lu)\n", i++, csc->dname, (u_long)csc->pid);
942 	return (0);
943 }
944 
945 /*
946  * cscope_search --
947  *	Search a file for a cscope entry.
948  *
949  * PUBLIC: int cscope_search __P((SCR *, TAGQ *, TAG *));
950  */
951 int
952 cscope_search(SCR *sp, TAGQ *tqp, TAG *tp)
953 {
954 	MARK m;
955 
956 	/* If we don't have a search pattern, use the line number. */
957 	if (tp->search == NULL) {
958 		if (!db_exist(sp, tp->slno)) {
959 			tag_msg(sp, TAG_BADLNO, tqp->tag);
960 			return (1);
961 		}
962 		m.lno = tp->slno;
963 	} else {
964 		/*
965 		 * Search for the tag; cheap fallback for C functions
966 		 * if the name is the same but the arguments have changed.
967 		 */
968 		m.lno = 1;
969 		m.cno = 0;
970 		if (f_search(sp, &m, &m,
971 		    tp->search, tp->slen, NULL, SEARCH_CSCOPE | SEARCH_FIRST)) {
972 			tag_msg(sp, TAG_SEARCH, tqp->tag);
973 			return (1);
974 		}
975 
976 		/*
977 		 * !!!
978 		 * Historically, tags set the search direction if it wasn't
979 		 * already set.
980 		 */
981 		if (sp->searchdir == NOTSET)
982 			sp->searchdir = FORWARD;
983 	}
984 
985 	/*
986 	 * !!!
987 	 * Tags move to the first non-blank, NOT the search pattern start.
988 	 */
989 	sp->lno = m.lno;
990 	sp->cno = 0;
991 	(void)nonblank(sp, sp->lno, &sp->cno);
992 	return (0);
993 }
994 
995 
996 /*
997  * lookup_ccmd --
998  *	Return a pointer to the command structure.
999  */
1000 static CC const *
1001 lookup_ccmd(const char *name)
1002 {
1003 	CC const *ccp;
1004 	size_t len;
1005 
1006 	len = strlen(name);
1007 	for (ccp = cscope_cmds; ccp->name != NULL; ++ccp)
1008 		if (strncmp(name, ccp->name, len) == 0)
1009 			return (ccp);
1010 	return (NULL);
1011 }
1012 
1013 /*
1014  * read_prompt --
1015  *	Read a prompt from cscope.
1016  */
1017 static int
1018 read_prompt(SCR *sp, CSC *csc)
1019 {
1020 	int ch;
1021 
1022 #define	CSCOPE_PROMPT		">> "
1023 	for (;;) {
1024 		while ((ch =
1025 		    getc(csc->from_fp)) != EOF && ch != CSCOPE_PROMPT[0]);
1026 		if (ch == EOF) {
1027 			terminate(sp, csc, 0);
1028 			return (1);
1029 		}
1030 		if (getc(csc->from_fp) != CSCOPE_PROMPT[1])
1031 			continue;
1032 		if (getc(csc->from_fp) != CSCOPE_PROMPT[2])
1033 			continue;
1034 		break;
1035 	}
1036 	return (0);
1037 }
1038