xref: /vim-8.2.3635/src/ex_eval.c (revision 577fadfc)
1 /* vi:set ts=8 sts=4 sw=4 noet:
2  *
3  * VIM - Vi IMproved	by Bram Moolenaar
4  *
5  * Do ":help uganda"  in Vim to read copying and usage conditions.
6  * Do ":help credits" in Vim to see a list of people who contributed.
7  * See README.txt for an overview of the Vim source code.
8  */
9 
10 /*
11  * ex_eval.c: functions for Ex command line for the +eval feature.
12  */
13 
14 #include "vim.h"
15 
16 #if defined(FEAT_EVAL) || defined(PROTO)
17 
18 static int	throw_exception(void *, except_type_T, char_u *);
19 static char	*get_end_emsg(struct condstack *cstack);
20 
21 /*
22  * Exception handling terms:
23  *
24  *	:try		":try" command		\
25  *	    ...		try block		|
26  *	:catch RE	":catch" command	|
27  *	    ...		catch clause		|- try conditional
28  *	:finally	":finally" command	|
29  *	    ...		finally clause		|
30  *	:endtry		":endtry" command	/
31  *
32  * The try conditional may have any number of catch clauses and at most one
33  * finally clause.  A ":throw" command can be inside the try block, a catch
34  * clause, the finally clause, or in a function called or script sourced from
35  * there or even outside the try conditional.  Try conditionals may be nested.
36  */
37 
38 /*
39  * Configuration whether an exception is thrown on error or interrupt.  When
40  * the preprocessor macros below evaluate to FALSE, an error (did_emsg) or
41  * interrupt (got_int) under an active try conditional terminates the script
42  * after the non-active finally clauses of all active try conditionals have been
43  * executed.  Otherwise, errors and/or interrupts are converted into catchable
44  * exceptions (did_throw additionally set), which terminate the script only if
45  * not caught.  For user exceptions, only did_throw is set.  (Note: got_int can
46  * be set asynchronously afterwards by a SIGINT, so did_throw && got_int is not
47  * a reliant test that the exception currently being thrown is an interrupt
48  * exception.  Similarly, did_emsg can be set afterwards on an error in an
49  * (unskipped) conditional command inside an inactive conditional, so did_throw
50  * && did_emsg is not a reliant test that the exception currently being thrown
51  * is an error exception.)  -  The macros can be defined as expressions checking
52  * for a variable that is allowed to be changed during execution of a script.
53  */
54 #if 0
55 /* Expressions used for testing during the development phase. */
56 # define THROW_ON_ERROR		(!eval_to_number("$VIMNOERRTHROW"))
57 # define THROW_ON_INTERRUPT	(!eval_to_number("$VIMNOINTTHROW"))
58 # define THROW_TEST
59 #else
60 /* Values used for the Vim release. */
61 # define THROW_ON_ERROR		TRUE
62 # define THROW_ON_ERROR_TRUE
63 # define THROW_ON_INTERRUPT	TRUE
64 # define THROW_ON_INTERRUPT_TRUE
65 #endif
66 
67 /*
68  * When several errors appear in a row, setting "force_abort" is delayed until
69  * the failing command returned.  "cause_abort" is set to TRUE meanwhile, in
70  * order to indicate that situation.  This is useful when "force_abort" was set
71  * during execution of a function call from an expression: the aborting of the
72  * expression evaluation is done without producing any error messages, but all
73  * error messages on parsing errors during the expression evaluation are given
74  * (even if a try conditional is active).
75  */
76 static int cause_abort = FALSE;
77 
78 /*
79  * Return TRUE when immediately aborting on error, or when an interrupt
80  * occurred or an exception was thrown but not caught.  Use for ":{range}call"
81  * to check whether an aborted function that does not handle a range itself
82  * should be called again for the next line in the range.  Also used for
83  * cancelling expression evaluation after a function call caused an immediate
84  * abort.  Note that the first emsg() call temporarily resets "force_abort"
85  * until the throw point for error messages has been reached.  That is, during
86  * cancellation of an expression evaluation after an aborting function call or
87  * due to a parsing error, aborting() always returns the same value.
88  */
89     int
90 aborting(void)
91 {
92     return (did_emsg && force_abort) || got_int || did_throw;
93 }
94 
95 /*
96  * The value of "force_abort" is temporarily reset by the first emsg() call
97  * during an expression evaluation, and "cause_abort" is used instead.  It might
98  * be necessary to restore "force_abort" even before the throw point for the
99  * error message has been reached.  update_force_abort() should be called then.
100  */
101     void
102 update_force_abort(void)
103 {
104     if (cause_abort)
105 	force_abort = TRUE;
106 }
107 
108 /*
109  * Return TRUE if a command with a subcommand resulting in "retcode" should
110  * abort the script processing.  Can be used to suppress an autocommand after
111  * execution of a failing subcommand as long as the error message has not been
112  * displayed and actually caused the abortion.
113  */
114     int
115 should_abort(int retcode)
116 {
117     return ((retcode == FAIL && trylevel != 0 && !emsg_silent) || aborting());
118 }
119 
120 /*
121  * Return TRUE if a function with the "abort" flag should not be considered
122  * ended on an error.  This means that parsing commands is continued in order
123  * to find finally clauses to be executed, and that some errors in skipped
124  * commands are still reported.
125  */
126     int
127 aborted_in_try(void)
128 {
129     /* This function is only called after an error.  In this case, "force_abort"
130      * determines whether searching for finally clauses is necessary. */
131     return force_abort;
132 }
133 
134 /*
135  * cause_errthrow(): Cause a throw of an error exception if appropriate.
136  * Return TRUE if the error message should not be displayed by emsg().
137  * Sets "ignore", if the emsg() call should be ignored completely.
138  *
139  * When several messages appear in the same command, the first is usually the
140  * most specific one and used as the exception value.  The "severe" flag can be
141  * set to TRUE, if a later but severer message should be used instead.
142  */
143     int
144 cause_errthrow(
145     char_u	*mesg,
146     int		severe,
147     int		*ignore)
148 {
149     struct msglist *elem;
150     struct msglist **plist;
151 
152     /*
153      * Do nothing when displaying the interrupt message or reporting an
154      * uncaught exception (which has already been discarded then) at the top
155      * level.  Also when no exception can be thrown.  The message will be
156      * displayed by emsg().
157      */
158     if (suppress_errthrow)
159 	return FALSE;
160 
161     /*
162      * If emsg() has not been called previously, temporarily reset
163      * "force_abort" until the throw point for error messages has been
164      * reached.  This ensures that aborting() returns the same value for all
165      * errors that appear in the same command.  This means particularly that
166      * for parsing errors during expression evaluation emsg() will be called
167      * multiply, even when the expression is evaluated from a finally clause
168      * that was activated due to an aborting error, interrupt, or exception.
169      */
170     if (!did_emsg)
171     {
172 	cause_abort = force_abort;
173 	force_abort = FALSE;
174     }
175 
176     /*
177      * If no try conditional is active and no exception is being thrown and
178      * there has not been an error in a try conditional or a throw so far, do
179      * nothing (for compatibility of non-EH scripts).  The message will then
180      * be displayed by emsg().  When ":silent!" was used and we are not
181      * currently throwing an exception, do nothing.  The message text will
182      * then be stored to v:errmsg by emsg() without displaying it.
183      */
184     if (((trylevel == 0 && !cause_abort) || emsg_silent) && !did_throw)
185 	return FALSE;
186 
187     /*
188      * Ignore an interrupt message when inside a try conditional or when an
189      * exception is being thrown or when an error in a try conditional or
190      * throw has been detected previously.  This is important in order that an
191      * interrupt exception is catchable by the innermost try conditional and
192      * not replaced by an interrupt message error exception.
193      */
194     if (mesg == (char_u *)_(e_interr))
195     {
196 	*ignore = TRUE;
197 	return TRUE;
198     }
199 
200     /*
201      * Ensure that all commands in nested function calls and sourced files
202      * are aborted immediately.
203      */
204     cause_abort = TRUE;
205 
206     /*
207      * When an exception is being thrown, some commands (like conditionals) are
208      * not skipped.  Errors in those commands may affect what of the subsequent
209      * commands are regarded part of catch and finally clauses.  Catching the
210      * exception would then cause execution of commands not intended by the
211      * user, who wouldn't even get aware of the problem.  Therefor, discard the
212      * exception currently being thrown to prevent it from being caught.  Just
213      * execute finally clauses and terminate.
214      */
215     if (did_throw)
216     {
217 	/* When discarding an interrupt exception, reset got_int to prevent the
218 	 * same interrupt being converted to an exception again and discarding
219 	 * the error exception we are about to throw here. */
220 	if (current_exception->type == ET_INTERRUPT)
221 	    got_int = FALSE;
222 	discard_current_exception();
223     }
224 
225 #ifdef THROW_TEST
226     if (!THROW_ON_ERROR)
227     {
228 	/*
229 	 * Print error message immediately without searching for a matching
230 	 * catch clause; just finally clauses are executed before the script
231 	 * is terminated.
232 	 */
233 	return FALSE;
234     }
235     else
236 #endif
237     {
238 	/*
239 	 * Prepare the throw of an error exception, so that everything will
240 	 * be aborted (except for executing finally clauses), until the error
241 	 * exception is caught; if still uncaught at the top level, the error
242 	 * message will be displayed and the script processing terminated
243 	 * then.  -  This function has no access to the conditional stack.
244 	 * Thus, the actual throw is made after the failing command has
245 	 * returned.  -  Throw only the first of several errors in a row, except
246 	 * a severe error is following.
247 	 */
248 	if (msg_list != NULL)
249 	{
250 	    plist = msg_list;
251 	    while (*plist != NULL)
252 		plist = &(*plist)->next;
253 
254 	    elem = (struct msglist *)alloc((unsigned)sizeof(struct msglist));
255 	    if (elem == NULL)
256 	    {
257 		suppress_errthrow = TRUE;
258 		emsg(_(e_outofmem));
259 	    }
260 	    else
261 	    {
262 		elem->msg = (char *)vim_strsave(mesg);
263 		if (elem->msg == NULL)
264 		{
265 		    vim_free(elem);
266 		    suppress_errthrow = TRUE;
267 		    emsg(_(e_outofmem));
268 		}
269 		else
270 		{
271 		    elem->next = NULL;
272 		    elem->throw_msg = NULL;
273 		    *plist = elem;
274 		    if (plist == msg_list || severe)
275 		    {
276 			char	    *tmsg;
277 
278 			/* Skip the extra "Vim " prefix for message "E458". */
279 			tmsg = elem->msg;
280 			if (STRNCMP(tmsg, "Vim E", 5) == 0
281 				&& VIM_ISDIGIT(tmsg[5])
282 				&& VIM_ISDIGIT(tmsg[6])
283 				&& VIM_ISDIGIT(tmsg[7])
284 				&& tmsg[8] == ':'
285 				&& tmsg[9] == ' ')
286 			    (*msg_list)->throw_msg = &tmsg[4];
287 			else
288 			    (*msg_list)->throw_msg = tmsg;
289 		    }
290 		}
291 	    }
292 	}
293 	return TRUE;
294     }
295 }
296 
297 /*
298  * Free a "msg_list" and the messages it contains.
299  */
300     static void
301 free_msglist(struct msglist *l)
302 {
303     struct msglist  *messages, *next;
304 
305     messages = l;
306     while (messages != NULL)
307     {
308 	next = messages->next;
309 	vim_free(messages->msg);
310 	vim_free(messages);
311 	messages = next;
312     }
313 }
314 
315 /*
316  * Free global "*msg_list" and the messages it contains, then set "*msg_list"
317  * to NULL.
318  */
319     void
320 free_global_msglist(void)
321 {
322     free_msglist(*msg_list);
323     *msg_list = NULL;
324 }
325 
326 /*
327  * Throw the message specified in the call to cause_errthrow() above as an
328  * error exception.  If cstack is NULL, postpone the throw until do_cmdline()
329  * has returned (see do_one_cmd()).
330  */
331     void
332 do_errthrow(struct condstack *cstack, char_u *cmdname)
333 {
334     /*
335      * Ensure that all commands in nested function calls and sourced files
336      * are aborted immediately.
337      */
338     if (cause_abort)
339     {
340 	cause_abort = FALSE;
341 	force_abort = TRUE;
342     }
343 
344     /* If no exception is to be thrown or the conversion should be done after
345      * returning to a previous invocation of do_one_cmd(), do nothing. */
346     if (msg_list == NULL || *msg_list == NULL)
347 	return;
348 
349     if (throw_exception(*msg_list, ET_ERROR, cmdname) == FAIL)
350 	free_msglist(*msg_list);
351     else
352     {
353 	if (cstack != NULL)
354 	    do_throw(cstack);
355 	else
356 	    need_rethrow = TRUE;
357     }
358     *msg_list = NULL;
359 }
360 
361 /*
362  * do_intthrow(): Replace the current exception by an interrupt or interrupt
363  * exception if appropriate.  Return TRUE if the current exception is discarded,
364  * FALSE otherwise.
365  */
366     int
367 do_intthrow(struct condstack *cstack)
368 {
369     /*
370      * If no interrupt occurred or no try conditional is active and no exception
371      * is being thrown, do nothing (for compatibility of non-EH scripts).
372      */
373     if (!got_int || (trylevel == 0 && !did_throw))
374 	return FALSE;
375 
376 #ifdef THROW_TEST	/* avoid warning for condition always true */
377     if (!THROW_ON_INTERRUPT)
378     {
379 	/*
380 	 * The interrupt aborts everything except for executing finally clauses.
381 	 * Discard any user or error or interrupt exception currently being
382 	 * thrown.
383 	 */
384 	if (did_throw)
385 	    discard_current_exception();
386     }
387     else
388 #endif
389     {
390 	/*
391 	 * Throw an interrupt exception, so that everything will be aborted
392 	 * (except for executing finally clauses), until the interrupt exception
393 	 * is caught; if still uncaught at the top level, the script processing
394 	 * will be terminated then.  -  If an interrupt exception is already
395 	 * being thrown, do nothing.
396 	 *
397 	 */
398 	if (did_throw)
399 	{
400 	    if (current_exception->type == ET_INTERRUPT)
401 		return FALSE;
402 
403 	    /* An interrupt exception replaces any user or error exception. */
404 	    discard_current_exception();
405 	}
406 	if (throw_exception("Vim:Interrupt", ET_INTERRUPT, NULL) != FAIL)
407 	    do_throw(cstack);
408     }
409 
410     return TRUE;
411 }
412 
413 /*
414  * Get an exception message that is to be stored in current_exception->value.
415  */
416     char *
417 get_exception_string(
418     void	*value,
419     except_type_T type,
420     char_u	*cmdname,
421     int		*should_free)
422 {
423     char	*ret;
424     char	*mesg;
425     int		cmdlen;
426     char	*p, *val;
427 
428     if (type == ET_ERROR)
429     {
430 	*should_free = TRUE;
431 	mesg = ((struct msglist *)value)->throw_msg;
432 	if (cmdname != NULL && *cmdname != NUL)
433 	{
434 	    cmdlen = (int)STRLEN(cmdname);
435 	    ret = (char *)vim_strnsave((char_u *)"Vim(",
436 					   4 + cmdlen + 2 + (int)STRLEN(mesg));
437 	    if (ret == NULL)
438 		return ret;
439 	    STRCPY(&ret[4], cmdname);
440 	    STRCPY(&ret[4 + cmdlen], "):");
441 	    val = ret + 4 + cmdlen + 2;
442 	}
443 	else
444 	{
445 	    ret = (char *)vim_strnsave((char_u *)"Vim:", 4 + (int)STRLEN(mesg));
446 	    if (ret == NULL)
447 		return ret;
448 	    val = ret + 4;
449 	}
450 
451 	/* msg_add_fname may have been used to prefix the message with a file
452 	 * name in quotes.  In the exception value, put the file name in
453 	 * parentheses and move it to the end. */
454 	for (p = mesg; ; p++)
455 	{
456 	    if (*p == NUL
457 		    || (*p == 'E'
458 			&& VIM_ISDIGIT(p[1])
459 			&& (p[2] == ':'
460 			    || (VIM_ISDIGIT(p[2])
461 				&& (p[3] == ':'
462 				    || (VIM_ISDIGIT(p[3])
463 					&& p[4] == ':'))))))
464 	    {
465 		if (*p == NUL || p == mesg)
466 		    STRCAT(val, mesg);  /* 'E123' missing or at beginning */
467 		else
468 		{
469 		    /* '"filename" E123: message text' */
470 		    if (mesg[0] != '"' || p-2 < &mesg[1] ||
471 			    p[-2] != '"' || p[-1] != ' ')
472 			/* "E123:" is part of the file name. */
473 			continue;
474 
475 		    STRCAT(val, p);
476 		    p[-2] = NUL;
477 		    sprintf((char *)(val + STRLEN(p)), " (%s)", &mesg[1]);
478 		    p[-2] = '"';
479 		}
480 		break;
481 	    }
482 	}
483     }
484     else
485     {
486 	*should_free = FALSE;
487 	ret = value;
488     }
489 
490     return ret;
491 }
492 
493 
494 /*
495  * Throw a new exception.  Return FAIL when out of memory or it was tried to
496  * throw an illegal user exception.  "value" is the exception string for a
497  * user or interrupt exception, or points to a message list in case of an
498  * error exception.
499  */
500     static int
501 throw_exception(void *value, except_type_T type, char_u *cmdname)
502 {
503     except_T	*excp;
504     int		should_free;
505 
506     /*
507      * Disallow faking Interrupt or error exceptions as user exceptions.  They
508      * would be treated differently from real interrupt or error exceptions
509      * when no active try block is found, see do_cmdline().
510      */
511     if (type == ET_USER)
512     {
513 	if (STRNCMP((char_u *)value, "Vim", 3) == 0
514 		&& (((char_u *)value)[3] == NUL || ((char_u *)value)[3] == ':'
515 		    || ((char_u *)value)[3] == '('))
516 	{
517 	    emsg(_("E608: Cannot :throw exceptions with 'Vim' prefix"));
518 	    goto fail;
519 	}
520     }
521 
522     excp = (except_T *)alloc((unsigned)sizeof(except_T));
523     if (excp == NULL)
524 	goto nomem;
525 
526     if (type == ET_ERROR)
527 	/* Store the original message and prefix the exception value with
528 	 * "Vim:" or, if a command name is given, "Vim(cmdname):". */
529 	excp->messages = (struct msglist *)value;
530 
531     excp->value = get_exception_string(value, type, cmdname, &should_free);
532     if (excp->value == NULL && should_free)
533 	goto nomem;
534 
535     excp->type = type;
536     excp->throw_name = vim_strsave(sourcing_name == NULL
537 					      ? (char_u *)"" : sourcing_name);
538     if (excp->throw_name == NULL)
539     {
540 	if (should_free)
541 	    vim_free(excp->value);
542 	goto nomem;
543     }
544     excp->throw_lnum = sourcing_lnum;
545 
546     if (p_verbose >= 13 || debug_break_level > 0)
547     {
548 	int	save_msg_silent = msg_silent;
549 
550 	if (debug_break_level > 0)
551 	    msg_silent = FALSE;		/* display messages */
552 	else
553 	    verbose_enter();
554 	++no_wait_return;
555 	if (debug_break_level > 0 || *p_vfile == NUL)
556 	    msg_scroll = TRUE;	    /* always scroll up, don't overwrite */
557 
558 	smsg(_("Exception thrown: %s"), excp->value);
559 	msg_puts("\n");   /* don't overwrite this either */
560 
561 	if (debug_break_level > 0 || *p_vfile == NUL)
562 	    cmdline_row = msg_row;
563 	--no_wait_return;
564 	if (debug_break_level > 0)
565 	    msg_silent = save_msg_silent;
566 	else
567 	    verbose_leave();
568     }
569 
570     current_exception = excp;
571     return OK;
572 
573 nomem:
574     vim_free(excp);
575     suppress_errthrow = TRUE;
576     emsg(_(e_outofmem));
577 fail:
578     current_exception = NULL;
579     return FAIL;
580 }
581 
582 /*
583  * Discard an exception.  "was_finished" is set when the exception has been
584  * caught and the catch clause has been ended normally.
585  */
586     static void
587 discard_exception(except_T *excp, int was_finished)
588 {
589     char_u		*saved_IObuff;
590 
591     if (excp == NULL)
592     {
593 	internal_error("discard_exception()");
594 	return;
595     }
596 
597     if (p_verbose >= 13 || debug_break_level > 0)
598     {
599 	int	save_msg_silent = msg_silent;
600 
601 	saved_IObuff = vim_strsave(IObuff);
602 	if (debug_break_level > 0)
603 	    msg_silent = FALSE;		/* display messages */
604 	else
605 	    verbose_enter();
606 	++no_wait_return;
607 	if (debug_break_level > 0 || *p_vfile == NUL)
608 	    msg_scroll = TRUE;	    /* always scroll up, don't overwrite */
609 	smsg(was_finished
610 		    ? _("Exception finished: %s")
611 		    : _("Exception discarded: %s"),
612 		excp->value);
613 	msg_puts("\n");   /* don't overwrite this either */
614 	if (debug_break_level > 0 || *p_vfile == NUL)
615 	    cmdline_row = msg_row;
616 	--no_wait_return;
617 	if (debug_break_level > 0)
618 	    msg_silent = save_msg_silent;
619 	else
620 	    verbose_leave();
621 	STRCPY(IObuff, saved_IObuff);
622 	vim_free(saved_IObuff);
623     }
624     if (excp->type != ET_INTERRUPT)
625 	vim_free(excp->value);
626     if (excp->type == ET_ERROR)
627 	free_msglist(excp->messages);
628     vim_free(excp->throw_name);
629     vim_free(excp);
630 }
631 
632 /*
633  * Discard the exception currently being thrown.
634  */
635     void
636 discard_current_exception(void)
637 {
638     if (current_exception != NULL)
639     {
640 	discard_exception(current_exception, FALSE);
641 	current_exception = NULL;
642     }
643     did_throw = FALSE;
644     need_rethrow = FALSE;
645 }
646 
647 /*
648  * Put an exception on the caught stack.
649  */
650     static void
651 catch_exception(except_T *excp)
652 {
653     excp->caught = caught_stack;
654     caught_stack = excp;
655     set_vim_var_string(VV_EXCEPTION, (char_u *)excp->value, -1);
656     if (*excp->throw_name != NUL)
657     {
658 	if (excp->throw_lnum != 0)
659 	    vim_snprintf((char *)IObuff, IOSIZE, _("%s, line %ld"),
660 				    excp->throw_name, (long)excp->throw_lnum);
661 	else
662 	    vim_snprintf((char *)IObuff, IOSIZE, "%s", excp->throw_name);
663 	set_vim_var_string(VV_THROWPOINT, IObuff, -1);
664     }
665     else
666 	/* throw_name not set on an exception from a command that was typed. */
667 	set_vim_var_string(VV_THROWPOINT, NULL, -1);
668 
669     if (p_verbose >= 13 || debug_break_level > 0)
670     {
671 	int	save_msg_silent = msg_silent;
672 
673 	if (debug_break_level > 0)
674 	    msg_silent = FALSE;		/* display messages */
675 	else
676 	    verbose_enter();
677 	++no_wait_return;
678 	if (debug_break_level > 0 || *p_vfile == NUL)
679 	    msg_scroll = TRUE;	    /* always scroll up, don't overwrite */
680 
681 	smsg(_("Exception caught: %s"), excp->value);
682 	msg_puts("\n");   /* don't overwrite this either */
683 
684 	if (debug_break_level > 0 || *p_vfile == NUL)
685 	    cmdline_row = msg_row;
686 	--no_wait_return;
687 	if (debug_break_level > 0)
688 	    msg_silent = save_msg_silent;
689 	else
690 	    verbose_leave();
691     }
692 }
693 
694 /*
695  * Remove an exception from the caught stack.
696  */
697     static void
698 finish_exception(except_T *excp)
699 {
700     if (excp != caught_stack)
701 	internal_error("finish_exception()");
702     caught_stack = caught_stack->caught;
703     if (caught_stack != NULL)
704     {
705 	set_vim_var_string(VV_EXCEPTION, (char_u *)caught_stack->value, -1);
706 	if (*caught_stack->throw_name != NUL)
707 	{
708 	    if (caught_stack->throw_lnum != 0)
709 		vim_snprintf((char *)IObuff, IOSIZE,
710 			_("%s, line %ld"), caught_stack->throw_name,
711 			(long)caught_stack->throw_lnum);
712 	    else
713 		vim_snprintf((char *)IObuff, IOSIZE, "%s",
714 						    caught_stack->throw_name);
715 	    set_vim_var_string(VV_THROWPOINT, IObuff, -1);
716 	}
717 	else
718 	    /* throw_name not set on an exception from a command that was
719 	     * typed. */
720 	    set_vim_var_string(VV_THROWPOINT, NULL, -1);
721     }
722     else
723     {
724 	set_vim_var_string(VV_EXCEPTION, NULL, -1);
725 	set_vim_var_string(VV_THROWPOINT, NULL, -1);
726     }
727 
728     /* Discard the exception, but use the finish message for 'verbose'. */
729     discard_exception(excp, TRUE);
730 }
731 
732 /*
733  * Flags specifying the message displayed by report_pending.
734  */
735 #define RP_MAKE		0
736 #define RP_RESUME	1
737 #define RP_DISCARD	2
738 
739 /*
740  * Report information about something pending in a finally clause if required by
741  * the 'verbose' option or when debugging.  "action" tells whether something is
742  * made pending or something pending is resumed or discarded.  "pending" tells
743  * what is pending.  "value" specifies the return value for a pending ":return"
744  * or the exception value for a pending exception.
745  */
746     static void
747 report_pending(int action, int pending, void *value)
748 {
749     char	*mesg;
750     char	*s;
751     int		save_msg_silent;
752 
753 
754     switch (action)
755     {
756 	case RP_MAKE:
757 	    mesg = _("%s made pending");
758 	    break;
759 	case RP_RESUME:
760 	    mesg = _("%s resumed");
761 	    break;
762 	/* case RP_DISCARD: */
763 	default:
764 	    mesg = _("%s discarded");
765 	    break;
766     }
767 
768     switch (pending)
769     {
770 	case CSTP_NONE:
771 	    return;
772 
773 	case CSTP_CONTINUE:
774 	    s = ":continue";
775 	    break;
776 	case CSTP_BREAK:
777 	    s = ":break";
778 	    break;
779 	case CSTP_FINISH:
780 	    s = ":finish";
781 	    break;
782 	case CSTP_RETURN:
783 	    /* ":return" command producing value, allocated */
784 	    s = (char *)get_return_cmd(value);
785 	    break;
786 
787 	default:
788 	    if (pending & CSTP_THROW)
789 	    {
790 		vim_snprintf((char *)IObuff, IOSIZE, mesg, _("Exception"));
791 		mesg = (char *)vim_strnsave(IObuff, (int)STRLEN(IObuff) + 4);
792 		STRCAT(mesg, ": %s");
793 		s = (char *)((except_T *)value)->value;
794 	    }
795 	    else if ((pending & CSTP_ERROR) && (pending & CSTP_INTERRUPT))
796 		s = _("Error and interrupt");
797 	    else if (pending & CSTP_ERROR)
798 		s = _("Error");
799 	    else /* if (pending & CSTP_INTERRUPT) */
800 		s = _("Interrupt");
801     }
802 
803     save_msg_silent = msg_silent;
804     if (debug_break_level > 0)
805 	msg_silent = FALSE;	/* display messages */
806     ++no_wait_return;
807     msg_scroll = TRUE;		/* always scroll up, don't overwrite */
808     smsg(mesg, s);
809     msg_puts("\n");   /* don't overwrite this either */
810     cmdline_row = msg_row;
811     --no_wait_return;
812     if (debug_break_level > 0)
813 	msg_silent = save_msg_silent;
814 
815     if (pending == CSTP_RETURN)
816 	vim_free(s);
817     else if (pending & CSTP_THROW)
818 	vim_free(mesg);
819 }
820 
821 /*
822  * If something is made pending in a finally clause, report it if required by
823  * the 'verbose' option or when debugging.
824  */
825     void
826 report_make_pending(int pending, void *value)
827 {
828     if (p_verbose >= 14 || debug_break_level > 0)
829     {
830 	if (debug_break_level <= 0)
831 	    verbose_enter();
832 	report_pending(RP_MAKE, pending, value);
833 	if (debug_break_level <= 0)
834 	    verbose_leave();
835     }
836 }
837 
838 /*
839  * If something pending in a finally clause is resumed at the ":endtry", report
840  * it if required by the 'verbose' option or when debugging.
841  */
842     void
843 report_resume_pending(int pending, void *value)
844 {
845     if (p_verbose >= 14 || debug_break_level > 0)
846     {
847 	if (debug_break_level <= 0)
848 	    verbose_enter();
849 	report_pending(RP_RESUME, pending, value);
850 	if (debug_break_level <= 0)
851 	    verbose_leave();
852     }
853 }
854 
855 /*
856  * If something pending in a finally clause is discarded, report it if required
857  * by the 'verbose' option or when debugging.
858  */
859     void
860 report_discard_pending(int pending, void *value)
861 {
862     if (p_verbose >= 14 || debug_break_level > 0)
863     {
864 	if (debug_break_level <= 0)
865 	    verbose_enter();
866 	report_pending(RP_DISCARD, pending, value);
867 	if (debug_break_level <= 0)
868 	    verbose_leave();
869     }
870 }
871 
872 
873 /*
874  * ":if".
875  */
876     void
877 ex_if(exarg_T *eap)
878 {
879     int		error;
880     int		skip;
881     int		result;
882     struct condstack	*cstack = eap->cstack;
883 
884     if (cstack->cs_idx == CSTACK_LEN - 1)
885 	eap->errmsg = N_("E579: :if nesting too deep");
886     else
887     {
888 	++cstack->cs_idx;
889 	cstack->cs_flags[cstack->cs_idx] = 0;
890 
891 	/*
892 	 * Don't do something after an error, interrupt, or throw, or when there
893 	 * is a surrounding conditional and it was not active.
894 	 */
895 	skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0
896 		&& !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE));
897 
898 	result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip);
899 
900 	if (!skip && !error)
901 	{
902 	    if (result)
903 		cstack->cs_flags[cstack->cs_idx] = CSF_ACTIVE | CSF_TRUE;
904 	}
905 	else
906 	    /* set TRUE, so this conditional will never get active */
907 	    cstack->cs_flags[cstack->cs_idx] = CSF_TRUE;
908     }
909 }
910 
911 /*
912  * ":endif".
913  */
914     void
915 ex_endif(exarg_T *eap)
916 {
917     did_endif = TRUE;
918     if (eap->cstack->cs_idx < 0
919 	    || (eap->cstack->cs_flags[eap->cstack->cs_idx]
920 					   & (CSF_WHILE | CSF_FOR | CSF_TRY)))
921 	eap->errmsg = N_("E580: :endif without :if");
922     else
923     {
924 	/*
925 	 * When debugging or a breakpoint was encountered, display the debug
926 	 * prompt (if not already done).  This shows the user that an ":endif"
927 	 * is executed when the ":if" or a previous ":elseif" was not TRUE.
928 	 * Handle a ">quit" debug command as if an interrupt had occurred before
929 	 * the ":endif".  That is, throw an interrupt exception if appropriate.
930 	 * Doing this here prevents an exception for a parsing error being
931 	 * discarded by throwing the interrupt exception later on.
932 	 */
933 	if (!(eap->cstack->cs_flags[eap->cstack->cs_idx] & CSF_TRUE)
934 						    && dbg_check_skipped(eap))
935 	    (void)do_intthrow(eap->cstack);
936 
937 	--eap->cstack->cs_idx;
938     }
939 }
940 
941 /*
942  * ":else" and ":elseif".
943  */
944     void
945 ex_else(exarg_T *eap)
946 {
947     int		error;
948     int		skip;
949     int		result;
950     struct condstack	*cstack = eap->cstack;
951 
952     /*
953      * Don't do something after an error, interrupt, or throw, or when there is
954      * a surrounding conditional and it was not active.
955      */
956     skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0
957 	    && !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE));
958 
959     if (cstack->cs_idx < 0
960 	    || (cstack->cs_flags[cstack->cs_idx]
961 					   & (CSF_WHILE | CSF_FOR | CSF_TRY)))
962     {
963 	if (eap->cmdidx == CMD_else)
964 	{
965 	    eap->errmsg = N_("E581: :else without :if");
966 	    return;
967 	}
968 	eap->errmsg = N_("E582: :elseif without :if");
969 	skip = TRUE;
970     }
971     else if (cstack->cs_flags[cstack->cs_idx] & CSF_ELSE)
972     {
973 	if (eap->cmdidx == CMD_else)
974 	{
975 	    eap->errmsg = N_("E583: multiple :else");
976 	    return;
977 	}
978 	eap->errmsg = N_("E584: :elseif after :else");
979 	skip = TRUE;
980     }
981 
982     /* if skipping or the ":if" was TRUE, reset ACTIVE, otherwise set it */
983     if (skip || cstack->cs_flags[cstack->cs_idx] & CSF_TRUE)
984     {
985 	if (eap->errmsg == NULL)
986 	    cstack->cs_flags[cstack->cs_idx] = CSF_TRUE;
987 	skip = TRUE;	/* don't evaluate an ":elseif" */
988     }
989     else
990 	cstack->cs_flags[cstack->cs_idx] = CSF_ACTIVE;
991 
992     /*
993      * When debugging or a breakpoint was encountered, display the debug prompt
994      * (if not already done).  This shows the user that an ":else" or ":elseif"
995      * is executed when the ":if" or previous ":elseif" was not TRUE.  Handle
996      * a ">quit" debug command as if an interrupt had occurred before the
997      * ":else" or ":elseif".  That is, set "skip" and throw an interrupt
998      * exception if appropriate.  Doing this here prevents that an exception
999      * for a parsing errors is discarded when throwing the interrupt exception
1000      * later on.
1001      */
1002     if (!skip && dbg_check_skipped(eap) && got_int)
1003     {
1004 	(void)do_intthrow(cstack);
1005 	skip = TRUE;
1006     }
1007 
1008     if (eap->cmdidx == CMD_elseif)
1009     {
1010 	result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip);
1011 	/* When throwing error exceptions, we want to throw always the first
1012 	 * of several errors in a row.  This is what actually happens when
1013 	 * a conditional error was detected above and there is another failure
1014 	 * when parsing the expression.  Since the skip flag is set in this
1015 	 * case, the parsing error will be ignored by emsg(). */
1016 
1017 	if (!skip && !error)
1018 	{
1019 	    if (result)
1020 		cstack->cs_flags[cstack->cs_idx] = CSF_ACTIVE | CSF_TRUE;
1021 	    else
1022 		cstack->cs_flags[cstack->cs_idx] = 0;
1023 	}
1024 	else if (eap->errmsg == NULL)
1025 	    /* set TRUE, so this conditional will never get active */
1026 	    cstack->cs_flags[cstack->cs_idx] = CSF_TRUE;
1027     }
1028     else
1029 	cstack->cs_flags[cstack->cs_idx] |= CSF_ELSE;
1030 }
1031 
1032 /*
1033  * Handle ":while" and ":for".
1034  */
1035     void
1036 ex_while(exarg_T *eap)
1037 {
1038     int		error;
1039     int		skip;
1040     int		result;
1041     struct condstack	*cstack = eap->cstack;
1042 
1043     if (cstack->cs_idx == CSTACK_LEN - 1)
1044 	eap->errmsg = N_("E585: :while/:for nesting too deep");
1045     else
1046     {
1047 	/*
1048 	 * The loop flag is set when we have jumped back from the matching
1049 	 * ":endwhile" or ":endfor".  When not set, need to initialise this
1050 	 * cstack entry.
1051 	 */
1052 	if ((cstack->cs_lflags & CSL_HAD_LOOP) == 0)
1053 	{
1054 	    ++cstack->cs_idx;
1055 	    ++cstack->cs_looplevel;
1056 	    cstack->cs_line[cstack->cs_idx] = -1;
1057 	}
1058 	cstack->cs_flags[cstack->cs_idx] =
1059 			       eap->cmdidx == CMD_while ? CSF_WHILE : CSF_FOR;
1060 
1061 	/*
1062 	 * Don't do something after an error, interrupt, or throw, or when
1063 	 * there is a surrounding conditional and it was not active.
1064 	 */
1065 	skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0
1066 		&& !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE));
1067 	if (eap->cmdidx == CMD_while)
1068 	{
1069 	    /*
1070 	     * ":while bool-expr"
1071 	     */
1072 	    result = eval_to_bool(eap->arg, &error, &eap->nextcmd, skip);
1073 	}
1074 	else
1075 	{
1076 	    void *fi;
1077 
1078 	    /*
1079 	     * ":for var in list-expr"
1080 	     */
1081 	    if ((cstack->cs_lflags & CSL_HAD_LOOP) != 0)
1082 	    {
1083 		/* Jumping here from a ":continue" or ":endfor": use the
1084 		 * previously evaluated list. */
1085 		fi = cstack->cs_forinfo[cstack->cs_idx];
1086 		error = FALSE;
1087 	    }
1088 	    else
1089 	    {
1090 		/* Evaluate the argument and get the info in a structure. */
1091 		fi = eval_for_line(eap->arg, &error, &eap->nextcmd, skip);
1092 		cstack->cs_forinfo[cstack->cs_idx] = fi;
1093 	    }
1094 
1095 	    /* use the element at the start of the list and advance */
1096 	    if (!error && fi != NULL && !skip)
1097 		result = next_for_item(fi, eap->arg);
1098 	    else
1099 		result = FALSE;
1100 
1101 	    if (!result)
1102 	    {
1103 		free_for_info(fi);
1104 		cstack->cs_forinfo[cstack->cs_idx] = NULL;
1105 	    }
1106 	}
1107 
1108 	/*
1109 	 * If this cstack entry was just initialised and is active, set the
1110 	 * loop flag, so do_cmdline() will set the line number in cs_line[].
1111 	 * If executing the command a second time, clear the loop flag.
1112 	 */
1113 	if (!skip && !error && result)
1114 	{
1115 	    cstack->cs_flags[cstack->cs_idx] |= (CSF_ACTIVE | CSF_TRUE);
1116 	    cstack->cs_lflags ^= CSL_HAD_LOOP;
1117 	}
1118 	else
1119 	{
1120 	    cstack->cs_lflags &= ~CSL_HAD_LOOP;
1121 	    /* If the ":while" evaluates to FALSE or ":for" is past the end of
1122 	     * the list, show the debug prompt at the ":endwhile"/":endfor" as
1123 	     * if there was a ":break" in a ":while"/":for" evaluating to
1124 	     * TRUE. */
1125 	    if (!skip && !error)
1126 		cstack->cs_flags[cstack->cs_idx] |= CSF_TRUE;
1127 	}
1128     }
1129 }
1130 
1131 /*
1132  * ":continue"
1133  */
1134     void
1135 ex_continue(exarg_T *eap)
1136 {
1137     int		idx;
1138     struct condstack	*cstack = eap->cstack;
1139 
1140     if (cstack->cs_looplevel <= 0 || cstack->cs_idx < 0)
1141 	eap->errmsg = N_("E586: :continue without :while or :for");
1142     else
1143     {
1144 	/* Try to find the matching ":while".  This might stop at a try
1145 	 * conditional not in its finally clause (which is then to be executed
1146 	 * next).  Therefor, inactivate all conditionals except the ":while"
1147 	 * itself (if reached). */
1148 	idx = cleanup_conditionals(cstack, CSF_WHILE | CSF_FOR, FALSE);
1149 	if (idx >= 0 && (cstack->cs_flags[idx] & (CSF_WHILE | CSF_FOR)))
1150 	{
1151 	    rewind_conditionals(cstack, idx, CSF_TRY, &cstack->cs_trylevel);
1152 
1153 	    /*
1154 	     * Set CSL_HAD_CONT, so do_cmdline() will jump back to the
1155 	     * matching ":while".
1156 	     */
1157 	    cstack->cs_lflags |= CSL_HAD_CONT;	/* let do_cmdline() handle it */
1158 	}
1159 	else
1160 	{
1161 	    /* If a try conditional not in its finally clause is reached first,
1162 	     * make the ":continue" pending for execution at the ":endtry". */
1163 	    cstack->cs_pending[idx] = CSTP_CONTINUE;
1164 	    report_make_pending(CSTP_CONTINUE, NULL);
1165 	}
1166     }
1167 }
1168 
1169 /*
1170  * ":break"
1171  */
1172     void
1173 ex_break(exarg_T *eap)
1174 {
1175     int		idx;
1176     struct condstack	*cstack = eap->cstack;
1177 
1178     if (cstack->cs_looplevel <= 0 || cstack->cs_idx < 0)
1179 	eap->errmsg = N_("E587: :break without :while or :for");
1180     else
1181     {
1182 	/* Inactivate conditionals until the matching ":while" or a try
1183 	 * conditional not in its finally clause (which is then to be
1184 	 * executed next) is found.  In the latter case, make the ":break"
1185 	 * pending for execution at the ":endtry". */
1186 	idx = cleanup_conditionals(cstack, CSF_WHILE | CSF_FOR, TRUE);
1187 	if (idx >= 0 && !(cstack->cs_flags[idx] & (CSF_WHILE | CSF_FOR)))
1188 	{
1189 	    cstack->cs_pending[idx] = CSTP_BREAK;
1190 	    report_make_pending(CSTP_BREAK, NULL);
1191 	}
1192     }
1193 }
1194 
1195 /*
1196  * ":endwhile" and ":endfor"
1197  */
1198     void
1199 ex_endwhile(exarg_T *eap)
1200 {
1201     struct condstack	*cstack = eap->cstack;
1202     int			idx;
1203     char		*err;
1204     int			csf;
1205     int			fl;
1206 
1207     if (eap->cmdidx == CMD_endwhile)
1208     {
1209 	err = e_while;
1210 	csf = CSF_WHILE;
1211     }
1212     else
1213     {
1214 	err = e_for;
1215 	csf = CSF_FOR;
1216     }
1217 
1218     if (cstack->cs_looplevel <= 0 || cstack->cs_idx < 0)
1219 	eap->errmsg = err;
1220     else
1221     {
1222 	fl =  cstack->cs_flags[cstack->cs_idx];
1223 	if (!(fl & csf))
1224 	{
1225 	    /* If we are in a ":while" or ":for" but used the wrong endloop
1226 	     * command, do not rewind to the next enclosing ":for"/":while". */
1227 	    if (fl & CSF_WHILE)
1228 		eap->errmsg = _("E732: Using :endfor with :while");
1229 	    else if (fl & CSF_FOR)
1230 		eap->errmsg = _("E733: Using :endwhile with :for");
1231 	}
1232 	if (!(fl & (CSF_WHILE | CSF_FOR)))
1233 	{
1234 	    if (!(fl & CSF_TRY))
1235 		eap->errmsg = e_endif;
1236 	    else if (fl & CSF_FINALLY)
1237 		eap->errmsg = e_endtry;
1238 	    /* Try to find the matching ":while" and report what's missing. */
1239 	    for (idx = cstack->cs_idx; idx > 0; --idx)
1240 	    {
1241 		fl =  cstack->cs_flags[idx];
1242 		if ((fl & CSF_TRY) && !(fl & CSF_FINALLY))
1243 		{
1244 		    /* Give up at a try conditional not in its finally clause.
1245 		     * Ignore the ":endwhile"/":endfor". */
1246 		    eap->errmsg = err;
1247 		    return;
1248 		}
1249 		if (fl & csf)
1250 		    break;
1251 	    }
1252 	    /* Cleanup and rewind all contained (and unclosed) conditionals. */
1253 	    (void)cleanup_conditionals(cstack, CSF_WHILE | CSF_FOR, FALSE);
1254 	    rewind_conditionals(cstack, idx, CSF_TRY, &cstack->cs_trylevel);
1255 	}
1256 
1257 	/*
1258 	 * When debugging or a breakpoint was encountered, display the debug
1259 	 * prompt (if not already done).  This shows the user that an
1260 	 * ":endwhile"/":endfor" is executed when the ":while" was not TRUE or
1261 	 * after a ":break".  Handle a ">quit" debug command as if an
1262 	 * interrupt had occurred before the ":endwhile"/":endfor".  That is,
1263 	 * throw an interrupt exception if appropriate.  Doing this here
1264 	 * prevents that an exception for a parsing error is discarded when
1265 	 * throwing the interrupt exception later on.
1266 	 */
1267 	else if (cstack->cs_flags[cstack->cs_idx] & CSF_TRUE
1268 		&& !(cstack->cs_flags[cstack->cs_idx] & CSF_ACTIVE)
1269 		&& dbg_check_skipped(eap))
1270 	    (void)do_intthrow(cstack);
1271 
1272 	/*
1273 	 * Set loop flag, so do_cmdline() will jump back to the matching
1274 	 * ":while" or ":for".
1275 	 */
1276 	cstack->cs_lflags |= CSL_HAD_ENDLOOP;
1277     }
1278 }
1279 
1280 
1281 /*
1282  * ":throw expr"
1283  */
1284     void
1285 ex_throw(exarg_T *eap)
1286 {
1287     char_u	*arg = eap->arg;
1288     char_u	*value;
1289 
1290     if (*arg != NUL && *arg != '|' && *arg != '\n')
1291 	value = eval_to_string_skip(arg, &eap->nextcmd, eap->skip);
1292     else
1293     {
1294 	emsg(_(e_argreq));
1295 	value = NULL;
1296     }
1297 
1298     /* On error or when an exception is thrown during argument evaluation, do
1299      * not throw. */
1300     if (!eap->skip && value != NULL)
1301     {
1302 	if (throw_exception(value, ET_USER, NULL) == FAIL)
1303 	    vim_free(value);
1304 	else
1305 	    do_throw(eap->cstack);
1306     }
1307 }
1308 
1309 /*
1310  * Throw the current exception through the specified cstack.  Common routine
1311  * for ":throw" (user exception) and error and interrupt exceptions.  Also
1312  * used for rethrowing an uncaught exception.
1313  */
1314     void
1315 do_throw(struct condstack *cstack)
1316 {
1317     int		idx;
1318     int		inactivate_try = FALSE;
1319 
1320     /*
1321      * Cleanup and inactivate up to the next surrounding try conditional that
1322      * is not in its finally clause.  Normally, do not inactivate the try
1323      * conditional itself, so that its ACTIVE flag can be tested below.  But
1324      * if a previous error or interrupt has not been converted to an exception,
1325      * inactivate the try conditional, too, as if the conversion had been done,
1326      * and reset the did_emsg or got_int flag, so this won't happen again at
1327      * the next surrounding try conditional.
1328      */
1329 #ifndef THROW_ON_ERROR_TRUE
1330     if (did_emsg && !THROW_ON_ERROR)
1331     {
1332 	inactivate_try = TRUE;
1333 	did_emsg = FALSE;
1334     }
1335 #endif
1336 #ifndef THROW_ON_INTERRUPT_TRUE
1337     if (got_int && !THROW_ON_INTERRUPT)
1338     {
1339 	inactivate_try = TRUE;
1340 	got_int = FALSE;
1341     }
1342 #endif
1343     idx = cleanup_conditionals(cstack, 0, inactivate_try);
1344     if (idx >= 0)
1345     {
1346 	/*
1347 	 * If this try conditional is active and we are before its first
1348 	 * ":catch", set THROWN so that the ":catch" commands will check
1349 	 * whether the exception matches.  When the exception came from any of
1350 	 * the catch clauses, it will be made pending at the ":finally" (if
1351 	 * present) and rethrown at the ":endtry".  This will also happen if
1352 	 * the try conditional is inactive.  This is the case when we are
1353 	 * throwing an exception due to an error or interrupt on the way from
1354 	 * a preceding ":continue", ":break", ":return", ":finish", error or
1355 	 * interrupt (not converted to an exception) to the finally clause or
1356 	 * from a preceding throw of a user or error or interrupt exception to
1357 	 * the matching catch clause or the finally clause.
1358 	 */
1359 	if (!(cstack->cs_flags[idx] & CSF_CAUGHT))
1360 	{
1361 	    if (cstack->cs_flags[idx] & CSF_ACTIVE)
1362 		cstack->cs_flags[idx] |= CSF_THROWN;
1363 	    else
1364 		/* THROWN may have already been set for a catchable exception
1365 		 * that has been discarded.  Ensure it is reset for the new
1366 		 * exception. */
1367 		cstack->cs_flags[idx] &= ~CSF_THROWN;
1368 	}
1369 	cstack->cs_flags[idx] &= ~CSF_ACTIVE;
1370 	cstack->cs_exception[idx] = current_exception;
1371     }
1372 #if 0
1373     /* TODO: Add optimization below.  Not yet done because of interface
1374      * problems to eval.c and ex_cmds2.c. (Servatius) */
1375     else
1376     {
1377 	/*
1378 	 * There are no catch clauses to check or finally clauses to execute.
1379 	 * End the current script or function.  The exception will be rethrown
1380 	 * in the caller.
1381 	 */
1382 	if (getline_equal(eap->getline, eap->cookie, get_func_line))
1383 	    current_funccal->returned = TRUE;
1384 	elseif (eap->get_func_line == getsourceline)
1385 	    ((struct source_cookie *)eap->cookie)->finished = TRUE;
1386     }
1387 #endif
1388 
1389     did_throw = TRUE;
1390 }
1391 
1392 /*
1393  * ":try"
1394  */
1395     void
1396 ex_try(exarg_T *eap)
1397 {
1398     int		skip;
1399     struct condstack	*cstack = eap->cstack;
1400 
1401     if (cstack->cs_idx == CSTACK_LEN - 1)
1402 	eap->errmsg = N_("E601: :try nesting too deep");
1403     else
1404     {
1405 	++cstack->cs_idx;
1406 	++cstack->cs_trylevel;
1407 	cstack->cs_flags[cstack->cs_idx] = CSF_TRY;
1408 	cstack->cs_pending[cstack->cs_idx] = CSTP_NONE;
1409 
1410 	/*
1411 	 * Don't do something after an error, interrupt, or throw, or when there
1412 	 * is a surrounding conditional and it was not active.
1413 	 */
1414 	skip = did_emsg || got_int || did_throw || (cstack->cs_idx > 0
1415 		&& !(cstack->cs_flags[cstack->cs_idx - 1] & CSF_ACTIVE));
1416 
1417 	if (!skip)
1418 	{
1419 	    /* Set ACTIVE and TRUE.  TRUE means that the corresponding ":catch"
1420 	     * commands should check for a match if an exception is thrown and
1421 	     * that the finally clause needs to be executed. */
1422 	    cstack->cs_flags[cstack->cs_idx] |= CSF_ACTIVE | CSF_TRUE;
1423 
1424 	    /*
1425 	     * ":silent!", even when used in a try conditional, disables
1426 	     * displaying of error messages and conversion of errors to
1427 	     * exceptions.  When the silent commands again open a try
1428 	     * conditional, save "emsg_silent" and reset it so that errors are
1429 	     * again converted to exceptions.  The value is restored when that
1430 	     * try conditional is left.  If it is left normally, the commands
1431 	     * following the ":endtry" are again silent.  If it is left by
1432 	     * a ":continue", ":break", ":return", or ":finish", the commands
1433 	     * executed next are again silent.  If it is left due to an
1434 	     * aborting error, an interrupt, or an exception, restoring
1435 	     * "emsg_silent" does not matter since we are already in the
1436 	     * aborting state and/or the exception has already been thrown.
1437 	     * The effect is then just freeing the memory that was allocated
1438 	     * to save the value.
1439 	     */
1440 	    if (emsg_silent)
1441 	    {
1442 		eslist_T	*elem;
1443 
1444 		elem = (eslist_T *)alloc((unsigned)sizeof(struct eslist_elem));
1445 		if (elem == NULL)
1446 		    emsg(_(e_outofmem));
1447 		else
1448 		{
1449 		    elem->saved_emsg_silent = emsg_silent;
1450 		    elem->next = cstack->cs_emsg_silent_list;
1451 		    cstack->cs_emsg_silent_list = elem;
1452 		    cstack->cs_flags[cstack->cs_idx] |= CSF_SILENT;
1453 		    emsg_silent = 0;
1454 		}
1455 	    }
1456 	}
1457 
1458     }
1459 }
1460 
1461 /*
1462  * ":catch /{pattern}/" and ":catch"
1463  */
1464     void
1465 ex_catch(exarg_T *eap)
1466 {
1467     int		idx = 0;
1468     int		give_up = FALSE;
1469     int		skip = FALSE;
1470     int		caught = FALSE;
1471     char_u	*end;
1472     int		save_char = 0;
1473     char_u	*save_cpo;
1474     regmatch_T	regmatch;
1475     int		prev_got_int;
1476     struct condstack	*cstack = eap->cstack;
1477     char_u	*pat;
1478 
1479     if (cstack->cs_trylevel <= 0 || cstack->cs_idx < 0)
1480     {
1481 	eap->errmsg = N_("E603: :catch without :try");
1482 	give_up = TRUE;
1483     }
1484     else
1485     {
1486 	if (!(cstack->cs_flags[cstack->cs_idx] & CSF_TRY))
1487 	{
1488 	    /* Report what's missing if the matching ":try" is not in its
1489 	     * finally clause. */
1490 	    eap->errmsg = get_end_emsg(cstack);
1491 	    skip = TRUE;
1492 	}
1493 	for (idx = cstack->cs_idx; idx > 0; --idx)
1494 	    if (cstack->cs_flags[idx] & CSF_TRY)
1495 		break;
1496 	if (cstack->cs_flags[idx] & CSF_FINALLY)
1497 	{
1498 	    /* Give up for a ":catch" after ":finally" and ignore it.
1499 	     * Just parse. */
1500 	    eap->errmsg = N_("E604: :catch after :finally");
1501 	    give_up = TRUE;
1502 	}
1503 	else
1504 	    rewind_conditionals(cstack, idx, CSF_WHILE | CSF_FOR,
1505 						       &cstack->cs_looplevel);
1506     }
1507 
1508     if (ends_excmd(*eap->arg))	/* no argument, catch all errors */
1509     {
1510 	pat = (char_u *)".*";
1511 	end = NULL;
1512 	eap->nextcmd = find_nextcmd(eap->arg);
1513     }
1514     else
1515     {
1516 	pat = eap->arg + 1;
1517 	end = skip_regexp(pat, *eap->arg, TRUE, NULL);
1518     }
1519 
1520     if (!give_up)
1521     {
1522 	/*
1523 	 * Don't do something when no exception has been thrown or when the
1524 	 * corresponding try block never got active (because of an inactive
1525 	 * surrounding conditional or after an error or interrupt or throw).
1526 	 */
1527 	if (!did_throw || !(cstack->cs_flags[idx] & CSF_TRUE))
1528 	    skip = TRUE;
1529 
1530 	/*
1531 	 * Check for a match only if an exception is thrown but not caught by
1532 	 * a previous ":catch".  An exception that has replaced a discarded
1533 	 * exception is not checked (THROWN is not set then).
1534 	 */
1535 	if (!skip && (cstack->cs_flags[idx] & CSF_THROWN)
1536 		&& !(cstack->cs_flags[idx] & CSF_CAUGHT))
1537 	{
1538 	    if (end != NULL && *end != NUL && !ends_excmd(*skipwhite(end + 1)))
1539 	    {
1540 		emsg(_(e_trailing));
1541 		return;
1542 	    }
1543 
1544 	    /* When debugging or a breakpoint was encountered, display the
1545 	     * debug prompt (if not already done) before checking for a match.
1546 	     * This is a helpful hint for the user when the regular expression
1547 	     * matching fails.  Handle a ">quit" debug command as if an
1548 	     * interrupt had occurred before the ":catch".  That is, discard
1549 	     * the original exception, replace it by an interrupt exception,
1550 	     * and don't catch it in this try block. */
1551 	    if (!dbg_check_skipped(eap) || !do_intthrow(cstack))
1552 	    {
1553 		/* Terminate the pattern and avoid the 'l' flag in 'cpoptions'
1554 		 * while compiling it. */
1555 		if (end != NULL)
1556 		{
1557 		    save_char = *end;
1558 		    *end = NUL;
1559 		}
1560 		save_cpo  = p_cpo;
1561 		p_cpo = (char_u *)"";
1562 		/* Disable error messages, it will make current_exception
1563 		 * invalid. */
1564 		++emsg_off;
1565 		regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
1566 		--emsg_off;
1567 		regmatch.rm_ic = FALSE;
1568 		if (end != NULL)
1569 		    *end = save_char;
1570 		p_cpo = save_cpo;
1571 		if (regmatch.regprog == NULL)
1572 		    semsg(_(e_invarg2), pat);
1573 		else
1574 		{
1575 		    /*
1576 		     * Save the value of got_int and reset it.  We don't want
1577 		     * a previous interruption cancel matching, only hitting
1578 		     * CTRL-C while matching should abort it.
1579 		     */
1580 		    prev_got_int = got_int;
1581 		    got_int = FALSE;
1582 		    caught = vim_regexec_nl(&regmatch,
1583 			       (char_u *)current_exception->value, (colnr_T)0);
1584 		    got_int |= prev_got_int;
1585 		    vim_regfree(regmatch.regprog);
1586 		}
1587 	    }
1588 	}
1589 
1590 	if (caught)
1591 	{
1592 	    /* Make this ":catch" clause active and reset did_emsg, got_int,
1593 	     * and did_throw.  Put the exception on the caught stack. */
1594 	    cstack->cs_flags[idx] |= CSF_ACTIVE | CSF_CAUGHT;
1595 	    did_emsg = got_int = did_throw = FALSE;
1596 	    catch_exception((except_T *)cstack->cs_exception[idx]);
1597 	    /* It's mandatory that the current exception is stored in the cstack
1598 	     * so that it can be discarded at the next ":catch", ":finally", or
1599 	     * ":endtry" or when the catch clause is left by a ":continue",
1600 	     * ":break", ":return", ":finish", error, interrupt, or another
1601 	     * exception. */
1602 	    if (cstack->cs_exception[cstack->cs_idx] != current_exception)
1603 		internal_error("ex_catch()");
1604 	}
1605 	else
1606 	{
1607 	    /*
1608 	     * If there is a preceding catch clause and it caught the exception,
1609 	     * finish the exception now.  This happens also after errors except
1610 	     * when this ":catch" was after the ":finally" or not within
1611 	     * a ":try".  Make the try conditional inactive so that the
1612 	     * following catch clauses are skipped.  On an error or interrupt
1613 	     * after the preceding try block or catch clause was left by
1614 	     * a ":continue", ":break", ":return", or ":finish", discard the
1615 	     * pending action.
1616 	     */
1617 	    cleanup_conditionals(cstack, CSF_TRY, TRUE);
1618 	}
1619     }
1620 
1621     if (end != NULL)
1622 	eap->nextcmd = find_nextcmd(end);
1623 }
1624 
1625 /*
1626  * ":finally"
1627  */
1628     void
1629 ex_finally(exarg_T *eap)
1630 {
1631     int		idx;
1632     int		skip = FALSE;
1633     int		pending = CSTP_NONE;
1634     struct condstack	*cstack = eap->cstack;
1635 
1636     if (cstack->cs_trylevel <= 0 || cstack->cs_idx < 0)
1637 	eap->errmsg = N_("E606: :finally without :try");
1638     else
1639     {
1640 	if (!(cstack->cs_flags[cstack->cs_idx] & CSF_TRY))
1641 	{
1642 	    eap->errmsg = get_end_emsg(cstack);
1643 	    for (idx = cstack->cs_idx - 1; idx > 0; --idx)
1644 		if (cstack->cs_flags[idx] & CSF_TRY)
1645 		    break;
1646 	    /* Make this error pending, so that the commands in the following
1647 	     * finally clause can be executed.  This overrules also a pending
1648 	     * ":continue", ":break", ":return", or ":finish". */
1649 	    pending = CSTP_ERROR;
1650 	}
1651 	else
1652 	    idx = cstack->cs_idx;
1653 
1654 	if (cstack->cs_flags[idx] & CSF_FINALLY)
1655 	{
1656 	    /* Give up for a multiple ":finally" and ignore it. */
1657 	    eap->errmsg = N_("E607: multiple :finally");
1658 	    return;
1659 	}
1660 	rewind_conditionals(cstack, idx, CSF_WHILE | CSF_FOR,
1661 						       &cstack->cs_looplevel);
1662 
1663 	/*
1664 	 * Don't do something when the corresponding try block never got active
1665 	 * (because of an inactive surrounding conditional or after an error or
1666 	 * interrupt or throw) or for a ":finally" without ":try" or a multiple
1667 	 * ":finally".  After every other error (did_emsg or the conditional
1668 	 * errors detected above) or after an interrupt (got_int) or an
1669 	 * exception (did_throw), the finally clause must be executed.
1670 	 */
1671 	skip = !(cstack->cs_flags[cstack->cs_idx] & CSF_TRUE);
1672 
1673 	if (!skip)
1674 	{
1675 	    /* When debugging or a breakpoint was encountered, display the
1676 	     * debug prompt (if not already done).  The user then knows that the
1677 	     * finally clause is executed. */
1678 	    if (dbg_check_skipped(eap))
1679 	    {
1680 		/* Handle a ">quit" debug command as if an interrupt had
1681 		 * occurred before the ":finally".  That is, discard the
1682 		 * original exception and replace it by an interrupt
1683 		 * exception. */
1684 		(void)do_intthrow(cstack);
1685 	    }
1686 
1687 	    /*
1688 	     * If there is a preceding catch clause and it caught the exception,
1689 	     * finish the exception now.  This happens also after errors except
1690 	     * when this is a multiple ":finally" or one not within a ":try".
1691 	     * After an error or interrupt, this also discards a pending
1692 	     * ":continue", ":break", ":finish", or ":return" from the preceding
1693 	     * try block or catch clause.
1694 	     */
1695 	    cleanup_conditionals(cstack, CSF_TRY, FALSE);
1696 
1697 	    /*
1698 	     * Make did_emsg, got_int, did_throw pending.  If set, they overrule
1699 	     * a pending ":continue", ":break", ":return", or ":finish".  Then
1700 	     * we have particularly to discard a pending return value (as done
1701 	     * by the call to cleanup_conditionals() above when did_emsg or
1702 	     * got_int is set).  The pending values are restored by the
1703 	     * ":endtry", except if there is a new error, interrupt, exception,
1704 	     * ":continue", ":break", ":return", or ":finish" in the following
1705 	     * finally clause.  A missing ":endwhile", ":endfor" or ":endif"
1706 	     * detected here is treated as if did_emsg and did_throw had
1707 	     * already been set, respectively in case that the error is not
1708 	     * converted to an exception, did_throw had already been unset.
1709 	     * We must not set did_emsg here since that would suppress the
1710 	     * error message.
1711 	     */
1712 	    if (pending == CSTP_ERROR || did_emsg || got_int || did_throw)
1713 	    {
1714 		if (cstack->cs_pending[cstack->cs_idx] == CSTP_RETURN)
1715 		{
1716 		    report_discard_pending(CSTP_RETURN,
1717 					   cstack->cs_rettv[cstack->cs_idx]);
1718 		    discard_pending_return(cstack->cs_rettv[cstack->cs_idx]);
1719 		}
1720 		if (pending == CSTP_ERROR && !did_emsg)
1721 		    pending |= (THROW_ON_ERROR) ? CSTP_THROW : 0;
1722 		else
1723 		    pending |= did_throw ? CSTP_THROW : 0;
1724 		pending |= did_emsg  ? CSTP_ERROR     : 0;
1725 		pending |= got_int   ? CSTP_INTERRUPT : 0;
1726 		cstack->cs_pending[cstack->cs_idx] = pending;
1727 
1728 		/* It's mandatory that the current exception is stored in the
1729 		 * cstack so that it can be rethrown at the ":endtry" or be
1730 		 * discarded if the finally clause is left by a ":continue",
1731 		 * ":break", ":return", ":finish", error, interrupt, or another
1732 		 * exception.  When emsg() is called for a missing ":endif" or
1733 		 * a missing ":endwhile"/":endfor" detected here, the
1734 		 * exception will be discarded. */
1735 		if (did_throw && cstack->cs_exception[cstack->cs_idx]
1736 							 != current_exception)
1737 		    internal_error("ex_finally()");
1738 	    }
1739 
1740 	    /*
1741 	     * Set CSL_HAD_FINA, so do_cmdline() will reset did_emsg,
1742 	     * got_int, and did_throw and make the finally clause active.
1743 	     * This will happen after emsg() has been called for a missing
1744 	     * ":endif" or a missing ":endwhile"/":endfor" detected here, so
1745 	     * that the following finally clause will be executed even then.
1746 	     */
1747 	    cstack->cs_lflags |= CSL_HAD_FINA;
1748 	}
1749     }
1750 }
1751 
1752 /*
1753  * ":endtry"
1754  */
1755     void
1756 ex_endtry(exarg_T *eap)
1757 {
1758     int		idx;
1759     int		skip;
1760     int		rethrow = FALSE;
1761     int		pending = CSTP_NONE;
1762     void	*rettv = NULL;
1763     struct condstack	*cstack = eap->cstack;
1764 
1765     if (cstack->cs_trylevel <= 0 || cstack->cs_idx < 0)
1766 	eap->errmsg = N_("E602: :endtry without :try");
1767     else
1768     {
1769 	/*
1770 	 * Don't do something after an error, interrupt or throw in the try
1771 	 * block, catch clause, or finally clause preceding this ":endtry" or
1772 	 * when an error or interrupt occurred after a ":continue", ":break",
1773 	 * ":return", or ":finish" in a try block or catch clause preceding this
1774 	 * ":endtry" or when the try block never got active (because of an
1775 	 * inactive surrounding conditional or after an error or interrupt or
1776 	 * throw) or when there is a surrounding conditional and it has been
1777 	 * made inactive by a ":continue", ":break", ":return", or ":finish" in
1778 	 * the finally clause.  The latter case need not be tested since then
1779 	 * anything pending has already been discarded. */
1780 	skip = did_emsg || got_int || did_throw ||
1781 	    !(cstack->cs_flags[cstack->cs_idx] & CSF_TRUE);
1782 
1783 	if (!(cstack->cs_flags[cstack->cs_idx] & CSF_TRY))
1784 	{
1785 	    eap->errmsg = get_end_emsg(cstack);
1786 	    /* Find the matching ":try" and report what's missing. */
1787 	    idx = cstack->cs_idx;
1788 	    do
1789 		--idx;
1790 	    while (idx > 0 && !(cstack->cs_flags[idx] & CSF_TRY));
1791 	    rewind_conditionals(cstack, idx, CSF_WHILE | CSF_FOR,
1792 						       &cstack->cs_looplevel);
1793 	    skip = TRUE;
1794 
1795 	    /*
1796 	     * If an exception is being thrown, discard it to prevent it from
1797 	     * being rethrown at the end of this function.  It would be
1798 	     * discarded by the error message, anyway.  Resets did_throw.
1799 	     * This does not affect the script termination due to the error
1800 	     * since "trylevel" is decremented after emsg() has been called.
1801 	     */
1802 	    if (did_throw)
1803 		discard_current_exception();
1804 	}
1805 	else
1806 	{
1807 	    idx = cstack->cs_idx;
1808 
1809 	    /*
1810 	     * If we stopped with the exception currently being thrown at this
1811 	     * try conditional since we didn't know that it doesn't have
1812 	     * a finally clause, we need to rethrow it after closing the try
1813 	     * conditional.
1814 	     */
1815 	    if (did_throw && (cstack->cs_flags[idx] & CSF_TRUE)
1816 		    && !(cstack->cs_flags[idx] & CSF_FINALLY))
1817 		rethrow = TRUE;
1818 	}
1819 
1820 	/* If there was no finally clause, show the user when debugging or
1821 	 * a breakpoint was encountered that the end of the try conditional has
1822 	 * been reached: display the debug prompt (if not already done).  Do
1823 	 * this on normal control flow or when an exception was thrown, but not
1824 	 * on an interrupt or error not converted to an exception or when
1825 	 * a ":break", ":continue", ":return", or ":finish" is pending.  These
1826 	 * actions are carried out immediately.
1827 	 */
1828 	if ((rethrow || (!skip
1829 			&& !(cstack->cs_flags[idx] & CSF_FINALLY)
1830 			&& !cstack->cs_pending[idx]))
1831 		&& dbg_check_skipped(eap))
1832 	{
1833 	    /* Handle a ">quit" debug command as if an interrupt had occurred
1834 	     * before the ":endtry".  That is, throw an interrupt exception and
1835 	     * set "skip" and "rethrow". */
1836 	    if (got_int)
1837 	    {
1838 		skip = TRUE;
1839 		(void)do_intthrow(cstack);
1840 		/* The do_intthrow() call may have reset did_throw or
1841 		 * cstack->cs_pending[idx].*/
1842 		rethrow = FALSE;
1843 		if (did_throw && !(cstack->cs_flags[idx] & CSF_FINALLY))
1844 		    rethrow = TRUE;
1845 	    }
1846 	}
1847 
1848 	/*
1849 	 * If a ":return" is pending, we need to resume it after closing the
1850 	 * try conditional; remember the return value.  If there was a finally
1851 	 * clause making an exception pending, we need to rethrow it.  Make it
1852 	 * the exception currently being thrown.
1853 	 */
1854 	if (!skip)
1855 	{
1856 	    pending = cstack->cs_pending[idx];
1857 	    cstack->cs_pending[idx] = CSTP_NONE;
1858 	    if (pending == CSTP_RETURN)
1859 		rettv = cstack->cs_rettv[idx];
1860 	    else if (pending & CSTP_THROW)
1861 		current_exception = cstack->cs_exception[idx];
1862 	}
1863 
1864 	/*
1865 	 * Discard anything pending on an error, interrupt, or throw in the
1866 	 * finally clause.  If there was no ":finally", discard a pending
1867 	 * ":continue", ":break", ":return", or ":finish" if an error or
1868 	 * interrupt occurred afterwards, but before the ":endtry" was reached.
1869 	 * If an exception was caught by the last of the catch clauses and there
1870 	 * was no finally clause, finish the exception now.  This happens also
1871 	 * after errors except when this ":endtry" is not within a ":try".
1872 	 * Restore "emsg_silent" if it has been reset by this try conditional.
1873 	 */
1874 	(void)cleanup_conditionals(cstack, CSF_TRY | CSF_SILENT, TRUE);
1875 
1876 	--cstack->cs_idx;
1877 	--cstack->cs_trylevel;
1878 
1879 	if (!skip)
1880 	{
1881 	    report_resume_pending(pending,
1882 		    (pending == CSTP_RETURN) ? rettv :
1883 		    (pending & CSTP_THROW) ? (void *)current_exception : NULL);
1884 	    switch (pending)
1885 	    {
1886 		case CSTP_NONE:
1887 		    break;
1888 
1889 		/* Reactivate a pending ":continue", ":break", ":return",
1890 		 * ":finish" from the try block or a catch clause of this try
1891 		 * conditional.  This is skipped, if there was an error in an
1892 		 * (unskipped) conditional command or an interrupt afterwards
1893 		 * or if the finally clause is present and executed a new error,
1894 		 * interrupt, throw, ":continue", ":break", ":return", or
1895 		 * ":finish". */
1896 		case CSTP_CONTINUE:
1897 		    ex_continue(eap);
1898 		    break;
1899 		case CSTP_BREAK:
1900 		    ex_break(eap);
1901 		    break;
1902 		case CSTP_RETURN:
1903 		    do_return(eap, FALSE, FALSE, rettv);
1904 		    break;
1905 		case CSTP_FINISH:
1906 		    do_finish(eap, FALSE);
1907 		    break;
1908 
1909 		/* When the finally clause was entered due to an error,
1910 		 * interrupt or throw (as opposed to a ":continue", ":break",
1911 		 * ":return", or ":finish"), restore the pending values of
1912 		 * did_emsg, got_int, and did_throw.  This is skipped, if there
1913 		 * was a new error, interrupt, throw, ":continue", ":break",
1914 		 * ":return", or ":finish".  in the finally clause. */
1915 		default:
1916 		    if (pending & CSTP_ERROR)
1917 			did_emsg = TRUE;
1918 		    if (pending & CSTP_INTERRUPT)
1919 			got_int = TRUE;
1920 		    if (pending & CSTP_THROW)
1921 			rethrow = TRUE;
1922 		    break;
1923 	    }
1924 	}
1925 
1926 	if (rethrow)
1927 	    /* Rethrow the current exception (within this cstack). */
1928 	    do_throw(cstack);
1929     }
1930 }
1931 
1932 /*
1933  * enter_cleanup() and leave_cleanup()
1934  *
1935  * Functions to be called before/after invoking a sequence of autocommands for
1936  * cleanup for a failed command.  (Failure means here that a call to emsg()
1937  * has been made, an interrupt occurred, or there is an uncaught exception
1938  * from a previous autocommand execution of the same command.)
1939  *
1940  * Call enter_cleanup() with a pointer to a cleanup_T and pass the same
1941  * pointer to leave_cleanup().  The cleanup_T structure stores the pending
1942  * error/interrupt/exception state.
1943  */
1944 
1945 /*
1946  * This function works a bit like ex_finally() except that there was not
1947  * actually an extra try block around the part that failed and an error or
1948  * interrupt has not (yet) been converted to an exception.  This function
1949  * saves the error/interrupt/ exception state and prepares for the call to
1950  * do_cmdline() that is going to be made for the cleanup autocommand
1951  * execution.
1952  */
1953     void
1954 enter_cleanup(cleanup_T *csp)
1955 {
1956     int		pending = CSTP_NONE;
1957 
1958     /*
1959      * Postpone did_emsg, got_int, did_throw.  The pending values will be
1960      * restored by leave_cleanup() except if there was an aborting error,
1961      * interrupt, or uncaught exception after this function ends.
1962      */
1963     if (did_emsg || got_int || did_throw || need_rethrow)
1964     {
1965 	csp->pending = (did_emsg     ? CSTP_ERROR     : 0)
1966 		     | (got_int      ? CSTP_INTERRUPT : 0)
1967 		     | (did_throw    ? CSTP_THROW     : 0)
1968 		     | (need_rethrow ? CSTP_THROW     : 0);
1969 
1970 	/* If we are currently throwing an exception (did_throw), save it as
1971 	 * well.  On an error not yet converted to an exception, update
1972 	 * "force_abort" and reset "cause_abort" (as do_errthrow() would do).
1973 	 * This is needed for the do_cmdline() call that is going to be made
1974 	 * for autocommand execution.  We need not save *msg_list because
1975 	 * there is an extra instance for every call of do_cmdline(), anyway.
1976 	 */
1977 	if (did_throw || need_rethrow)
1978 	{
1979 	    csp->exception = current_exception;
1980 	    current_exception = NULL;
1981 	}
1982 	else
1983 	{
1984 	    csp->exception = NULL;
1985 	    if (did_emsg)
1986 	    {
1987 		force_abort |= cause_abort;
1988 		cause_abort = FALSE;
1989 	    }
1990 	}
1991 	did_emsg = got_int = did_throw = need_rethrow = FALSE;
1992 
1993 	/* Report if required by the 'verbose' option or when debugging.  */
1994 	report_make_pending(pending, csp->exception);
1995     }
1996     else
1997     {
1998 	csp->pending = CSTP_NONE;
1999 	csp->exception = NULL;
2000     }
2001 }
2002 
2003 /*
2004  * See comment above enter_cleanup() for how this function is used.
2005  *
2006  * This function is a bit like ex_endtry() except that there was not actually
2007  * an extra try block around the part that failed and an error or interrupt
2008  * had not (yet) been converted to an exception when the cleanup autocommand
2009  * sequence was invoked.
2010  *
2011  * This function has to be called with the address of the cleanup_T structure
2012  * filled by enter_cleanup() as an argument; it restores the error/interrupt/
2013  * exception state saved by that function - except there was an aborting
2014  * error, an interrupt or an uncaught exception during execution of the
2015  * cleanup autocommands.  In the latter case, the saved error/interrupt/
2016  * exception state is discarded.
2017  */
2018     void
2019 leave_cleanup(cleanup_T *csp)
2020 {
2021     int		pending = csp->pending;
2022 
2023     if (pending == CSTP_NONE)	/* nothing to do */
2024 	return;
2025 
2026     /* If there was an aborting error, an interrupt, or an uncaught exception
2027      * after the corresponding call to enter_cleanup(), discard what has been
2028      * made pending by it.  Report this to the user if required by the
2029      * 'verbose' option or when debugging. */
2030     if (aborting() || need_rethrow)
2031     {
2032 	if (pending & CSTP_THROW)
2033 	    /* Cancel the pending exception (includes report). */
2034 	    discard_exception((except_T *)csp->exception, FALSE);
2035 	else
2036 	    report_discard_pending(pending, NULL);
2037 
2038 	/* If an error was about to be converted to an exception when
2039 	 * enter_cleanup() was called, free the message list. */
2040 	if (msg_list != NULL)
2041 	    free_global_msglist();
2042     }
2043 
2044     /*
2045      * If there was no new error, interrupt, or throw between the calls
2046      * to enter_cleanup() and leave_cleanup(), restore the pending
2047      * error/interrupt/exception state.
2048      */
2049     else
2050     {
2051 	/*
2052 	 * If there was an exception being thrown when enter_cleanup() was
2053 	 * called, we need to rethrow it.  Make it the exception currently
2054 	 * being thrown.
2055 	 */
2056 	if (pending & CSTP_THROW)
2057 	    current_exception = csp->exception;
2058 
2059 	/*
2060 	 * If an error was about to be converted to an exception when
2061 	 * enter_cleanup() was called, let "cause_abort" take the part of
2062 	 * "force_abort" (as done by cause_errthrow()).
2063 	 */
2064 	else if (pending & CSTP_ERROR)
2065 	{
2066 	    cause_abort = force_abort;
2067 	    force_abort = FALSE;
2068 	}
2069 
2070 	/*
2071 	 * Restore the pending values of did_emsg, got_int, and did_throw.
2072 	 */
2073 	if (pending & CSTP_ERROR)
2074 	    did_emsg = TRUE;
2075 	if (pending & CSTP_INTERRUPT)
2076 	    got_int = TRUE;
2077 	if (pending & CSTP_THROW)
2078 	    need_rethrow = TRUE;    /* did_throw will be set by do_one_cmd() */
2079 
2080 	/* Report if required by the 'verbose' option or when debugging. */
2081 	report_resume_pending(pending,
2082 		   (pending & CSTP_THROW) ? (void *)current_exception : NULL);
2083     }
2084 }
2085 
2086 
2087 /*
2088  * Make conditionals inactive and discard what's pending in finally clauses
2089  * until the conditional type searched for or a try conditional not in its
2090  * finally clause is reached.  If this is in an active catch clause, finish
2091  * the caught exception.
2092  * Return the cstack index where the search stopped.
2093  * Values used for "searched_cond" are (CSF_WHILE | CSF_FOR) or CSF_TRY or 0,
2094  * the latter meaning the innermost try conditional not in its finally clause.
2095  * "inclusive" tells whether the conditional searched for should be made
2096  * inactive itself (a try conditional not in its finally clause possibly find
2097  * before is always made inactive).  If "inclusive" is TRUE and
2098  * "searched_cond" is CSF_TRY|CSF_SILENT, the saved former value of
2099  * "emsg_silent", if reset when the try conditional finally reached was
2100  * entered, is restored (used by ex_endtry()).  This is normally done only
2101  * when such a try conditional is left.
2102  */
2103     int
2104 cleanup_conditionals(
2105     struct condstack   *cstack,
2106     int		searched_cond,
2107     int		inclusive)
2108 {
2109     int		idx;
2110     int		stop = FALSE;
2111 
2112     for (idx = cstack->cs_idx; idx >= 0; --idx)
2113     {
2114 	if (cstack->cs_flags[idx] & CSF_TRY)
2115 	{
2116 	    /*
2117 	     * Discard anything pending in a finally clause and continue the
2118 	     * search.  There may also be a pending ":continue", ":break",
2119 	     * ":return", or ":finish" before the finally clause.  We must not
2120 	     * discard it, unless an error or interrupt occurred afterwards.
2121 	     */
2122 	    if (did_emsg || got_int || (cstack->cs_flags[idx] & CSF_FINALLY))
2123 	    {
2124 		switch (cstack->cs_pending[idx])
2125 		{
2126 		    case CSTP_NONE:
2127 			break;
2128 
2129 		    case CSTP_CONTINUE:
2130 		    case CSTP_BREAK:
2131 		    case CSTP_FINISH:
2132 			report_discard_pending(cstack->cs_pending[idx], NULL);
2133 			cstack->cs_pending[idx] = CSTP_NONE;
2134 			break;
2135 
2136 		    case CSTP_RETURN:
2137 			report_discard_pending(CSTP_RETURN,
2138 						      cstack->cs_rettv[idx]);
2139 			discard_pending_return(cstack->cs_rettv[idx]);
2140 			cstack->cs_pending[idx] = CSTP_NONE;
2141 			break;
2142 
2143 		    default:
2144 			if (cstack->cs_flags[idx] & CSF_FINALLY)
2145 			{
2146 			    if (cstack->cs_pending[idx] & CSTP_THROW)
2147 			    {
2148 				/* Cancel the pending exception.  This is in the
2149 				 * finally clause, so that the stack of the
2150 				 * caught exceptions is not involved. */
2151 				discard_exception((except_T *)
2152 					cstack->cs_exception[idx],
2153 					FALSE);
2154 			    }
2155 			    else
2156 				report_discard_pending(cstack->cs_pending[idx],
2157 					NULL);
2158 			    cstack->cs_pending[idx] = CSTP_NONE;
2159 			}
2160 			break;
2161 		}
2162 	    }
2163 
2164 	    /*
2165 	     * Stop at a try conditional not in its finally clause.  If this try
2166 	     * conditional is in an active catch clause, finish the caught
2167 	     * exception.
2168 	     */
2169 	    if (!(cstack->cs_flags[idx] & CSF_FINALLY))
2170 	    {
2171 		if ((cstack->cs_flags[idx] & CSF_ACTIVE)
2172 			&& (cstack->cs_flags[idx] & CSF_CAUGHT))
2173 		    finish_exception((except_T *)cstack->cs_exception[idx]);
2174 		/* Stop at this try conditional - except the try block never
2175 		 * got active (because of an inactive surrounding conditional
2176 		 * or when the ":try" appeared after an error or interrupt or
2177 		 * throw). */
2178 		if (cstack->cs_flags[idx] & CSF_TRUE)
2179 		{
2180 		    if (searched_cond == 0 && !inclusive)
2181 			break;
2182 		    stop = TRUE;
2183 		}
2184 	    }
2185 	}
2186 
2187 	/* Stop on the searched conditional type (even when the surrounding
2188 	 * conditional is not active or something has been made pending).
2189 	 * If "inclusive" is TRUE and "searched_cond" is CSF_TRY|CSF_SILENT,
2190 	 * check first whether "emsg_silent" needs to be restored. */
2191 	if (cstack->cs_flags[idx] & searched_cond)
2192 	{
2193 	    if (!inclusive)
2194 		break;
2195 	    stop = TRUE;
2196 	}
2197 	cstack->cs_flags[idx] &= ~CSF_ACTIVE;
2198 	if (stop && searched_cond != (CSF_TRY | CSF_SILENT))
2199 	    break;
2200 
2201 	/*
2202 	 * When leaving a try conditional that reset "emsg_silent" on its
2203 	 * entry after saving the original value, restore that value here and
2204 	 * free the memory used to store it.
2205 	 */
2206 	if ((cstack->cs_flags[idx] & CSF_TRY)
2207 		&& (cstack->cs_flags[idx] & CSF_SILENT))
2208 	{
2209 	    eslist_T	*elem;
2210 
2211 	    elem = cstack->cs_emsg_silent_list;
2212 	    cstack->cs_emsg_silent_list = elem->next;
2213 	    emsg_silent = elem->saved_emsg_silent;
2214 	    vim_free(elem);
2215 	    cstack->cs_flags[idx] &= ~CSF_SILENT;
2216 	}
2217 	if (stop)
2218 	    break;
2219     }
2220     return idx;
2221 }
2222 
2223 /*
2224  * Return an appropriate error message for a missing endwhile/endfor/endif.
2225  */
2226    static char *
2227 get_end_emsg(struct condstack *cstack)
2228 {
2229     if (cstack->cs_flags[cstack->cs_idx] & CSF_WHILE)
2230 	return e_endwhile;
2231     if (cstack->cs_flags[cstack->cs_idx] & CSF_FOR)
2232 	return e_endfor;
2233     return e_endif;
2234 }
2235 
2236 
2237 /*
2238  * Rewind conditionals until index "idx" is reached.  "cond_type" and
2239  * "cond_level" specify a conditional type and the address of a level variable
2240  * which is to be decremented with each skipped conditional of the specified
2241  * type.
2242  * Also free "for info" structures where needed.
2243  */
2244     void
2245 rewind_conditionals(
2246     struct condstack   *cstack,
2247     int		idx,
2248     int		cond_type,
2249     int		*cond_level)
2250 {
2251     while (cstack->cs_idx > idx)
2252     {
2253 	if (cstack->cs_flags[cstack->cs_idx] & cond_type)
2254 	    --*cond_level;
2255 	if (cstack->cs_flags[cstack->cs_idx] & CSF_FOR)
2256 	    free_for_info(cstack->cs_forinfo[cstack->cs_idx]);
2257 	--cstack->cs_idx;
2258     }
2259 }
2260 
2261 /*
2262  * ":endfunction" when not after a ":function"
2263  */
2264     void
2265 ex_endfunction(exarg_T *eap UNUSED)
2266 {
2267     emsg(_("E193: :endfunction not inside a function"));
2268 }
2269 
2270 /*
2271  * Return TRUE if the string "p" looks like a ":while" or ":for" command.
2272  */
2273     int
2274 has_loop_cmd(char_u *p)
2275 {
2276     int		len;
2277 
2278     /* skip modifiers, white space and ':' */
2279     for (;;)
2280     {
2281 	while (*p == ' ' || *p == '\t' || *p == ':')
2282 	    ++p;
2283 	len = modifier_len(p);
2284 	if (len == 0)
2285 	    break;
2286 	p += len;
2287     }
2288     if ((p[0] == 'w' && p[1] == 'h')
2289 	    || (p[0] == 'f' && p[1] == 'o' && p[2] == 'r'))
2290 	return TRUE;
2291     return FALSE;
2292 }
2293 
2294 #endif /* FEAT_EVAL */
2295