xref: /netbsd-src/lib/libform/internals.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: internals.c,v 1.32 2006/04/09 00:44:40 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998-1999 Brett Lymn
5  *                         (blymn@baea.com.au, brett_lymn@yahoo.com.au)
6  * All rights reserved.
7  *
8  * This code has been donated to The NetBSD Foundation by the Author.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  *
30  */
31 
32 #include <sys/cdefs.h>
33 __RCSID("$NetBSD: internals.c,v 1.32 2006/04/09 00:44:40 christos Exp $");
34 
35 #include <limits.h>
36 #include <ctype.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <strings.h>
40 #include <assert.h>
41 #include "internals.h"
42 #include "form.h"
43 
44 #ifdef DEBUG
45 /*
46  *  file handle to write debug info to, this will be initialised when
47  *  the form is first posted.
48  */
49 FILE *dbg = NULL;
50 
51 /*
52  * map the request numbers to strings for debug
53  */
54 char *reqs[] = {
55 	"NEXT_PAGE", "PREV_PAGE", "FIRST_PAGE",	"LAST_PAGE", "NEXT_FIELD",
56 	"PREV_FIELD", "FIRST_FIELD", "LAST_FIELD", "SNEXT_FIELD",
57 	"SPREV_FIELD", "SFIRST_FIELD", "SLAST_FIELD", "LEFT_FIELD",
58 	"RIGHT_FIELD", "UP_FIELD", "DOWN_FIELD", "NEXT_CHAR", "PREV_CHAR",
59 	"NEXT_LINE", "PREV_LINE", "NEXT_WORD", "PREV_WORD", "BEG_FIELD",
60 	"END_FIELD", "BEG_LINE", "END_LINE", "LEFT_CHAR", "RIGHT_CHAR",
61 	"UP_CHAR", "DOWN_CHAR", "NEW_LINE", "INS_CHAR", "INS_LINE",
62 	"DEL_CHAR", "DEL_PREV", "DEL_LINE", "DEL_WORD", "CLR_EOL",
63 	"CLR_EOF", "CLR_FIELD", "OVL_MODE", "INS_MODE", "SCR_FLINE",
64 	"SCR_BLINE", "SCR_FPAGE", "SCR_BPAGE", "SCR_FHPAGE", "SCR_BHPAGE",
65 	"SCR_FCHAR", "SCR_BCHAR", "SCR_HFLINE", "SCR_HBLINE", "SCR_HFHALF",
66 	"SCR_HBHALF", "VALIDATION", "PREV_CHOICE", "NEXT_CHOICE" };
67 #endif
68 
69 /* define our own min function - this is not generic but will do here
70  * (don't believe me?  think about what value you would get
71  * from min(x++, y++)
72  */
73 #define min(a,b) (((a) > (b))? (b) : (a))
74 
75 /* for the line joining function... */
76 #define JOIN_NEXT    1
77 #define JOIN_NEXT_NW 2 /* next join, don't wrap the joined line */
78 #define JOIN_PREV    3
79 #define JOIN_PREV_NW 4 /* previous join, don't wrap the joined line */
80 
81 /* for the bump_lines function... */
82 #define _FORMI_USE_CURRENT -1 /* indicates current cursor pos to be used */
83 
84 /* used in add_char for initial memory allocation for string in row */
85 #define INITIAL_LINE_ALLOC 16
86 
87 unsigned
88 field_skip_blanks(unsigned int start, _FORMI_FIELD_LINES **rowp);
89 static void
90 _formi_do_char_validation(FIELD *field, FIELDTYPE *type, char c, int *ret_val);
91 static void
92 _formi_do_validation(FIELD *field, FIELDTYPE *type, int *ret_val);
93 static int
94 _formi_join_line(FIELD *field, _FORMI_FIELD_LINES **rowp, int direction);
95 void
96 _formi_hscroll_back(FIELD *field, _FORMI_FIELD_LINES *row, unsigned int amt);
97 void
98 _formi_hscroll_fwd(FIELD *field, _FORMI_FIELD_LINES *row, unsigned int amt);
99 static void
100 _formi_scroll_back(FIELD *field, unsigned int amt);
101 static void
102 _formi_scroll_fwd(FIELD *field, unsigned int amt);
103 static int
104 _formi_set_cursor_xpos(FIELD *field, int no_scroll);
105 static int
106 find_sow(unsigned int offset, _FORMI_FIELD_LINES **rowp);
107 static int
108 split_line(FIELD *field, bool hard_split, unsigned pos,
109 	   _FORMI_FIELD_LINES **rowp);
110 static bool
111 check_field_size(FIELD *field);
112 static int
113 add_tab(FORM *form, _FORMI_FIELD_LINES *row, unsigned int i, char c);
114 static int
115 tab_size(_FORMI_FIELD_LINES *row, unsigned int i);
116 static unsigned int
117 tab_fit_len(_FORMI_FIELD_LINES *row, unsigned int len);
118 static int
119 tab_fit_window(FIELD *field, unsigned int pos, unsigned int window);
120 static void
121 add_to_free(FIELD *field, _FORMI_FIELD_LINES *line);
122 static void
123 adjust_ypos(FIELD *field, _FORMI_FIELD_LINES *line);
124 static _FORMI_FIELD_LINES *
125 copy_row(_FORMI_FIELD_LINES *row);
126 static void
127 destroy_row_list(_FORMI_FIELD_LINES *start);
128 
129 /*
130  * Calculate the cursor y position to make the given row appear on the
131  * field.  This may be as simple as just changing the ypos (if at all) but
132  * may encompass resetting the start_line of the field to place the line
133  * at the bottom of the field.  The field is assumed to be a multi-line one.
134  */
135 static void
136 adjust_ypos(FIELD *field, _FORMI_FIELD_LINES *line)
137 {
138 	unsigned ypos;
139 	_FORMI_FIELD_LINES *rs;
140 
141 	ypos = 0;
142 	rs = field->lines;
143 	while (rs != line) {
144 		rs = rs->next;
145 		ypos++;
146 	}
147 
148 	field->cursor_ypos = ypos;
149 	field->start_line = field->lines;
150 	if (ypos > (field->rows - 1)) {
151 		  /*
152 		   * cur_line off the end of the field,
153 		   * adjust start_line so fix this.
154 		   */
155 		field->cursor_ypos = field->rows - 1;
156 		ypos = ypos - (field->rows - 1);
157 		while (ypos > 0) {
158 			ypos--;
159 			field->start_line = field->start_line->next;
160 		}
161 	}
162 }
163 
164 
165 /*
166  * Delete the given row and add it to the free list of the given field.
167  */
168 static void
169 add_to_free(FIELD *field, _FORMI_FIELD_LINES *line)
170 {
171 	_FORMI_FIELD_LINES *saved;
172 
173 	saved = line;
174 
175 	  /* don't remove if only one line... */
176 	if ((line->prev == NULL) && (line->next == NULL))
177 		return;
178 
179 	if (line->prev == NULL) {
180 		/* handle top of list */
181 		field->lines = line->next;
182 		field->lines->prev = NULL;
183 
184 		if (field->cur_line == saved)
185 			field->cur_line = field->lines;
186 		if (field->start_line == saved)
187 			field->start_line = saved;
188 	} else if (line->next == NULL) {
189 		/* handle bottom of list */
190 		line->prev->next = NULL;
191 		if (field->cur_line == saved)
192 			field->cur_line = saved->prev;
193 		if (field->start_line == saved)
194 			field->cur_line = saved->prev;
195 	} else {
196 		saved->next->prev = saved->prev;
197 		saved->prev->next = saved->next;
198 		if (field->cur_line == saved)
199 			field->cur_line = saved->prev;
200 		if (field->start_line == saved)
201 			field->start_line = saved;
202 	}
203 
204 	saved->next = field->free;
205 	field->free = saved;
206 	saved->prev = NULL;
207 	if (saved->next != NULL)
208 		saved->next->prev = line;
209 }
210 
211 /*
212  * Duplicate the given row, return the pointer to the new copy or
213  * NULL if the copy fails.
214  */
215 static _FORMI_FIELD_LINES *
216 copy_row(_FORMI_FIELD_LINES *row)
217 {
218 	_FORMI_FIELD_LINES *new;
219 	_formi_tab_t *tp, *newt;
220 
221 	if ((new = (_FORMI_FIELD_LINES *) malloc(sizeof(_FORMI_FIELD_LINES)))
222 	    == NULL) {
223 		return NULL;
224 	}
225 
226 	memcpy(new, row, sizeof(_FORMI_FIELD_LINES));
227 
228 	  /* nuke the pointers from the source row so we don't get confused */
229 	new->next = NULL;
230 	new->prev = NULL;
231 	new->tabs = NULL;
232 
233 	if ((new->string = (char *) malloc((size_t)new->allocated)) == NULL) {
234 		free(new);
235 		return NULL;
236 	}
237 
238 	memcpy(new->string, row->string, (size_t) row->length + 1);
239 
240 	if (row->tabs != NULL) {
241 		tp = row->tabs;
242 		if ((new->tabs = (_formi_tab_t *) malloc(sizeof(_formi_tab_t)))
243 		    == NULL) {
244 			free(new->string);
245 			free(new);
246 			return NULL;
247 		}
248 
249 		memcpy(new->tabs, row->tabs, sizeof(_formi_tab_t));
250 		new->tabs->back = NULL;
251 		new->tabs->fwd = NULL;
252 
253 		tp = tp->fwd;
254 		newt = new->tabs;
255 
256 		while (tp != NULL) {
257 			if ((newt->fwd =
258 			     (_formi_tab_t *) malloc(sizeof(_formi_tab_t)))
259 			    == NULL) {
260 				/* error... unwind allocations */
261 				tp = new->tabs;
262 				while (tp != NULL) {
263 					newt = tp->fwd;
264 					free(tp);
265 					tp = newt;
266 				}
267 
268 				free(new->string);
269 				free(new);
270 				return NULL;
271 			}
272 
273 			memcpy(newt->fwd, tp, sizeof(_formi_tab_t));
274 			newt->fwd->back = newt;
275 			newt = newt->fwd;
276 			newt->fwd = NULL;
277 			tp = tp->fwd;
278 		}
279 	}
280 
281 	return new;
282 }
283 
284 /*
285  * Initialise the row offset for a field, depending on the type of
286  * field it is and the type of justification used.  The justification
287  * is only used on static single line fields, everything else will
288  * have the cursor_xpos set to 0.
289  */
290 void
291 _formi_init_field_xpos(FIELD *field)
292 {
293 	  /* not static or is multi-line which are not justified, so 0 it is */
294 	if (((field->opts & O_STATIC) != O_STATIC) ||
295 	    ((field->rows + field->nrows) != 1)) {
296 		field->cursor_xpos = 0;
297 		return;
298 	}
299 
300 	switch (field->justification) {
301 	case JUSTIFY_RIGHT:
302 		field->cursor_xpos = field->cols - 1;
303 		break;
304 
305 	case JUSTIFY_CENTER:
306 		field->cursor_xpos = (field->cols - 1) / 2;
307 		break;
308 
309 	default: /* assume left justify */
310 		field->cursor_xpos = 0;
311 		break;
312 	}
313 }
314 
315 
316 /*
317  * Open the debug file if it is not already open....
318  */
319 #ifdef DEBUG
320 int
321 _formi_create_dbg_file(void)
322 {
323 	if (dbg == NULL) {
324 		dbg = fopen("___form_dbg.out", "w");
325 		if (dbg == NULL) {
326 			fprintf(stderr, "Cannot open debug file!\n");
327 			return E_SYSTEM_ERROR;
328 		}
329 	}
330 
331 	return E_OK;
332 }
333 #endif
334 
335 /*
336  * Check the sizing of the field, if the maximum size is set for a
337  * dynamic field then check that the number of rows or columns does
338  * not exceed the set maximum.  The decision to check the rows or
339  * columns is made on the basis of how many rows are in the field -
340  * one row means the max applies to the number of columns otherwise it
341  * applies to the number of rows.  If the row/column count is less
342  * than the maximum then return TRUE.
343  *
344  */
345 static bool
346 check_field_size(FIELD *field)
347 {
348 	if ((field->opts & O_STATIC) != O_STATIC) {
349 		  /* dynamic field */
350 		if (field->max == 0) /* unlimited */
351 			return TRUE;
352 
353 		if (field->rows == 1) {
354 			return (field->lines->length < field->max);
355 		} else {
356 			return (field->row_count <= field->max);
357 		}
358 	} else {
359 		if ((field->rows + field->nrows) == 1) {
360 			return (field->lines->length <= field->cols);
361 		} else {
362 			return (field->row_count <= (field->rows
363 						     + field->nrows));
364 		}
365 	}
366 }
367 
368 /*
369  * Set the form's current field to the first valid field on the page.
370  * Assume the fields have been sorted and stitched.
371  */
372 int
373 _formi_pos_first_field(FORM *form)
374 {
375 	FIELD *cur;
376 	int old_page;
377 
378 	old_page = form->page;
379 
380 	  /* scan forward for an active page....*/
381 	while (form->page_starts[form->page].in_use == 0) {
382 		form->page++;
383 		if (form->page > form->max_page) {
384 			form->page = old_page;
385 			return E_REQUEST_DENIED;
386 		}
387 	}
388 
389 	  /* then scan for a field we can use */
390 	cur = form->fields[form->page_starts[form->page].first];
391 	while ((cur->opts & (O_VISIBLE | O_ACTIVE))
392 	       != (O_VISIBLE | O_ACTIVE)) {
393 		cur = CIRCLEQ_NEXT(cur, glue);
394 		if (cur == (void *) &form->sorted_fields) {
395 			form->page = old_page;
396 			return E_REQUEST_DENIED;
397 		}
398 	}
399 
400 	form->cur_field = cur->index;
401 	return E_OK;
402 }
403 
404 /*
405  * Set the field to the next active and visible field, the fields are
406  * traversed in index order in the direction given.  If the parameter
407  * use_sorted is TRUE then the sorted field list will be traversed instead
408  * of using the field index.
409  */
410 int
411 _formi_pos_new_field(FORM *form, unsigned direction, unsigned use_sorted)
412 {
413 	FIELD *cur;
414 	int i;
415 
416 	i = form->cur_field;
417 	cur = form->fields[i];
418 
419 	do {
420 		if (direction == _FORMI_FORWARD) {
421 			if (use_sorted == TRUE) {
422 				if ((form->wrap == FALSE) &&
423 				    (cur == CIRCLEQ_LAST(&form->sorted_fields)))
424 					return E_REQUEST_DENIED;
425 				cur = CIRCLEQ_NEXT(cur, glue);
426 				i = cur->index;
427 			} else {
428 				if ((form->wrap == FALSE) &&
429 				    ((i + 1) >= form->field_count))
430 					return E_REQUEST_DENIED;
431 				i++;
432 				if (i >= form->field_count)
433 					i = 0;
434 			}
435 		} else {
436 			if (use_sorted == TRUE) {
437 				if ((form->wrap == FALSE) &&
438 				    (cur == CIRCLEQ_FIRST(&form->sorted_fields)))
439 					return E_REQUEST_DENIED;
440 				cur = CIRCLEQ_PREV(cur, glue);
441 				i = cur->index;
442 			} else {
443 				if ((form->wrap == FALSE) && (i <= 0))
444 					return E_REQUEST_DENIED;
445 				i--;
446 				if (i < 0)
447 					i = form->field_count - 1;
448 			}
449 		}
450 
451 		if ((form->fields[i]->opts & (O_VISIBLE | O_ACTIVE))
452 			== (O_VISIBLE | O_ACTIVE)) {
453 			form->cur_field = i;
454 			return E_OK;
455 		}
456 	}
457 	while (i != form->cur_field);
458 
459 	return E_REQUEST_DENIED;
460 }
461 
462 /*
463  * Destroy the list of line structs passed by freeing all allocated
464  * memory.
465  */
466 static void
467 destroy_row_list(_FORMI_FIELD_LINES *start)
468 {
469 	_FORMI_FIELD_LINES *temp, *row;
470 	_formi_tab_t *tt, *tp;
471 
472 	row = start;
473 	while (row != NULL) {
474 		if (row->tabs != NULL) {
475 			  /* free up the tab linked list... */
476 			tp = row->tabs;
477 			while (tp != NULL) {
478 				tt = tp->fwd;
479 				free(tp);
480 				tp = tt;
481 			}
482 		}
483 
484 		if (row->string != NULL)
485 			free(row->string);
486 
487 		temp = row->next;
488 		free(row);
489 		row = temp;
490 	}
491 }
492 
493 /*
494  * Word wrap the contents of the field's buffer 0 if this is allowed.
495  * If the wrap is successful, that is, the row count nor the buffer
496  * size is exceeded then the function will return E_OK, otherwise it
497  * will return E_REQUEST_DENIED.
498  */
499 int
500 _formi_wrap_field(FIELD *field, _FORMI_FIELD_LINES *loc)
501 {
502 	int width, wrap_err;
503 	unsigned int pos, saved_xpos, saved_ypos, saved_cur_xpos;
504 	unsigned int saved_row_count;
505 	_FORMI_FIELD_LINES *saved_row, *row, *row_backup, *saved_cur_line;
506 	_FORMI_FIELD_LINES *saved_start_line, *temp;
507 
508 	if ((field->opts & O_STATIC) == O_STATIC) {
509 		if ((field->rows + field->nrows) == 1) {
510 			return E_OK; /* cannot wrap a single line */
511 		}
512 		width = field->cols;
513 	} else {
514 		  /* if we are limited to one line then don't try to wrap */
515 		if ((field->drows + field->nrows) == 1) {
516 			return E_OK;
517 		}
518 
519 		  /*
520 		   * hueristic - if a dynamic field has more than one line
521 		   * on the screen then the field grows rows, otherwise
522 		   * it grows columns, effectively a single line field.
523 		   * This is documented AT&T behaviour.
524 		   */
525 		if (field->rows > 1) {
526 			width = field->cols;
527 		} else {
528 			return E_OK;
529 		}
530 	}
531 
532 	row = loc;
533 
534 	  /* if we are not at the top of the field then back up one
535 	   * row because we may be able to merge the current row into
536 	   * the one above.
537 	   */
538 	if (row->prev != NULL)
539 		row = row->prev;
540 
541 	saved_row = row;
542 	saved_xpos = field->row_xpos;
543 	saved_cur_xpos = field->cursor_xpos;
544 	saved_ypos = field->cursor_ypos;
545 	saved_row_count = field->row_count;
546 
547 	  /*
548 	   * Save a copy of the lines affected, just in case things
549 	   * don't work out.
550 	   */
551 	if ((row_backup = copy_row(row)) == NULL)
552 		return E_SYSTEM_ERROR;
553 
554 	temp = row_backup;
555 	row = row->next;
556 
557 	saved_cur_line = temp;
558 	saved_start_line = temp;
559 
560 	while (row != NULL) {
561 		if ((temp->next = copy_row(row)) == NULL) {
562 			  /* a row copy failed... free up allocations */
563 			destroy_row_list(row_backup);
564 			return E_SYSTEM_ERROR;
565 		}
566 
567 		temp->next->prev = temp;
568 		temp = temp->next;
569 
570 		if (row == field->start_line)
571 			saved_start_line = temp;
572 		if (row == field->cur_line)
573 			saved_cur_line = temp;
574 
575 		row = row->next;
576 	}
577 
578 	row = saved_row;
579 	while (row != NULL) {
580 		pos = row->length - 1;
581 		if (row->expanded < width) {
582 			  /* line may be too short, try joining some lines */
583 			if ((row->hard_ret == TRUE) && (row->next != NULL)) {
584 				/*
585 				 * Skip the line if it has a hard return
586 				 * and it is not the last, we cannot join
587 				 * anything to it.
588 				 */
589 				row = row->next;
590 				continue;
591 			}
592 
593 			if ((row->next == NULL)) {
594 				/*
595 				 * If there are no more lines and this line
596 				 * is too short then our job is over.
597 				 */
598 				break;
599 			}
600 
601 			if (_formi_join_line(field, &row,
602 					     JOIN_NEXT_NW) == E_OK) {
603 				continue;
604 			} else
605 				break;
606 		} else if (row->expanded > width) {
607 			  /* line is too long, split it */
608 
609 			  /*
610 			   * split on first whitespace before current word
611 			   * if the line has tabs we need to work out where
612 			   * the field border lies when the tabs are expanded.
613 			   */
614 			if (row->tabs == NULL) {
615 				pos = width - 1;
616 				if (pos >= row->expanded)
617 					pos = row->expanded - 1;
618 			} else {
619 				pos = tab_fit_len(row, field->cols);
620 			}
621 
622 			if ((!isblank(row->string[pos])) &&
623 			    ((field->opts & O_WRAP) == O_WRAP)) {
624 				if (!isblank(row->string[pos - 1]))
625 					pos = find_sow((unsigned int) pos,
626 						       &row);
627 				/*
628 				 * If we cannot split the line then return
629 				 * NO_ROOM so the driver can tell that it
630 				 * should not autoskip (if that is enabled)
631 				 */
632 				if ((pos == 0)
633 				    || (!isblank(row->string[pos - 1]))) {
634 					wrap_err = E_NO_ROOM;
635 					goto restore_and_exit;
636 				}
637 			}
638 
639 			  /* if we are at the end of the string and it has
640 			   * a trailing blank, don't wrap the blank.
641 			   */
642 			if ((row->next == NULL) && (pos == row->length - 1) &&
643 			    (isblank(row->string[pos])) &&
644 			    row->expanded <= field->cols)
645 				continue;
646 
647 			  /*
648 			   * otherwise, if we are still sitting on a
649 			   * blank but not at the end of the line
650 			   * move forward one char so the blank
651 			   * is on the line boundary.
652 			   */
653 			if ((isblank(row->string[pos])) &&
654 			    (pos != row->length - 1))
655 				pos++;
656 
657 			if (split_line(field, FALSE, pos, &row) != E_OK) {
658 				wrap_err = E_REQUEST_DENIED;
659 				goto restore_and_exit;
660 			}
661 		} else
662 			  /* line is exactly the right length, do next one */
663 			row = row->next;
664 	}
665 
666 	  /* Check if we have not run out of room */
667 	if ((((field->opts & O_STATIC) == O_STATIC) &&
668 	     field->row_count > (field->rows + field->nrows)) ||
669 	    ((field->max != 0) && (field->row_count > field->max))) {
670 
671 		wrap_err = E_REQUEST_DENIED;
672 
673 	  restore_and_exit:
674 		if (saved_row->prev == NULL) {
675 			field->lines = row_backup;
676 		} else {
677 			saved_row->prev->next = row_backup;
678 			row_backup->prev = saved_row->prev;
679 		}
680 
681 		field->row_xpos = saved_xpos;
682 		field->cursor_xpos = saved_cur_xpos;
683 		field->cursor_ypos = saved_ypos;
684 		field->row_count = saved_row_count;
685 		field->start_line = saved_start_line;
686 		field->cur_line = saved_cur_line;
687 
688 		destroy_row_list(saved_row);
689 		return wrap_err;
690 	}
691 
692 	destroy_row_list(row_backup);
693 	return E_OK;
694 }
695 
696 /*
697  * Join the two lines that surround the location pos, the type
698  * variable indicates the direction of the join, JOIN_NEXT will join
699  * the next line to the current line, JOIN_PREV will join the current
700  * line to the previous line, the new lines will be wrapped unless the
701  * _NW versions of the directions are used.  Returns E_OK if the join
702  * was successful or E_REQUEST_DENIED if the join cannot happen.
703  */
704 static int
705 _formi_join_line(FIELD *field, _FORMI_FIELD_LINES **rowp, int direction)
706 {
707 	int old_len, count;
708 	struct _formi_field_lines *saved;
709 	char *newp;
710 	_FORMI_FIELD_LINES *row = *rowp;
711 #ifdef DEBUG
712 	int dbg_ok = FALSE;
713 
714 	if (_formi_create_dbg_file() == E_OK) {
715 		dbg_ok = TRUE;
716 	}
717 
718 	if (dbg_ok == TRUE) {
719 		fprintf(dbg, "join_line: working on row %p, row_count = %d\n",
720 			row, field->row_count);
721 	}
722 #endif
723 
724 	if ((direction == JOIN_NEXT) || (direction == JOIN_NEXT_NW)) {
725 		  /*
726 		   * See if there is another line following, or if the
727 		   * line contains a hard return then we don't join
728 		   * any lines to it.
729 		   */
730 		if ((row->next == NULL) || (row->hard_ret == TRUE)) {
731 			return E_REQUEST_DENIED;
732 		}
733 
734 #ifdef DEBUG
735 		if (dbg_ok == TRUE) {
736 			fprintf(dbg,
737 			"join_line: join_next before length = %d, expanded = %d",
738 				row->length, row->expanded);
739 			fprintf(dbg,
740 				" :: next row length = %d, expanded = %d\n",
741 				row->length, row->expanded);
742 		}
743 #endif
744 
745 		if (row->allocated < (row->length + row->next->length + 1)) {
746 			if ((newp = realloc(row->string, (size_t)(row->length +
747 							  row->next->length
748 							  + 1))) == NULL)
749 				return E_REQUEST_DENIED;
750 			row->string = newp;
751 			row->allocated = row->length + row->next->length + 1;
752 		}
753 
754 		strcat(row->string, row->next->string);
755 		old_len = row->length;
756 		row->length += row->next->length;
757 		if (row->length > 0)
758 			row->expanded =
759 				_formi_tab_expanded_length(row->string, 0,
760 							   row->length - 1);
761 		else
762 			row->expanded = 0;
763 
764 		_formi_calculate_tabs(row);
765 		row->hard_ret = row->next->hard_ret;
766 
767 		  /* adjust current line if it is on the row being eaten */
768 		if (field->cur_line == row->next) {
769 			field->cur_line = row;
770 			field->row_xpos += old_len;
771 			field->cursor_xpos =
772 				_formi_tab_expanded_length(row->string, 0,
773 							   field->row_xpos);
774 			if (field->cursor_xpos > 0)
775 				field->cursor_xpos--;
776 
777 			if (field->cursor_ypos > 0)
778 				field->cursor_ypos--;
779 			else {
780 				if (field->start_line->prev != NULL)
781 					field->start_line =
782 						field->start_line->prev;
783 			}
784 		}
785 
786 		  /* remove joined line record from the row list */
787 		add_to_free(field, row->next);
788 
789 #ifdef DEBUG
790 		if (dbg_ok == TRUE) {
791 			fprintf(dbg,
792 				"join_line: exit length = %d, expanded = %d\n",
793 				row->length, row->expanded);
794 		}
795 #endif
796 	} else {
797 		if (row->prev == NULL) {
798 			return E_REQUEST_DENIED;
799 		}
800 
801 		saved = row->prev;
802 
803 		  /*
804 		   * Don't try to join if the line above has a hard
805 		   * return on it.
806 		   */
807 		if (saved->hard_ret == TRUE) {
808 			return E_REQUEST_DENIED;
809 		}
810 
811 #ifdef DEBUG
812 		if (dbg_ok == TRUE) {
813 			fprintf(dbg,
814 			"join_line: join_prev before length = %d, expanded = %d",
815 				row->length, row->expanded);
816 			fprintf(dbg,
817 				" :: prev row length = %d, expanded = %d\n",
818 				saved->length, saved->expanded);
819 		}
820 #endif
821 
822 		if (saved->allocated < (row->length + saved->length + 1)) {
823 			if ((newp = realloc(saved->string,
824 					    (size_t) (row->length +
825 						      saved->length
826 						      + 1))) == NULL)
827 				return E_REQUEST_DENIED;
828 			saved->string = newp;
829 			saved->allocated = row->length + saved->length + 1;
830 		}
831 
832 		strcat(saved->string, row->string);
833 		old_len = saved->length;
834 		saved->length += row->length;
835 		if (saved->length > 0)
836 			saved->expanded =
837 				_formi_tab_expanded_length(saved->string, 0,
838 							   saved->length - 1);
839 		else
840 			saved->length = 0;
841 
842 		saved->hard_ret = row->hard_ret;
843 
844 		  /* adjust current line if it was on the row being eaten */
845 		if (field->cur_line == row) {
846 			field->cur_line = saved;
847 			field->row_xpos += old_len;
848 			field->cursor_xpos =
849 				_formi_tab_expanded_length(saved->string, 0,
850 							   field->row_xpos);
851 			if (field->cursor_xpos > 0)
852 				field->cursor_xpos--;
853 		}
854 
855 		add_to_free(field, row);
856 
857 #ifdef DEBUG
858 		if (dbg_ok == TRUE) {
859 			fprintf(dbg,
860 				"join_line: exit length = %d, expanded = %d\n",
861 				saved->length, saved->expanded);
862 		}
863 #endif
864 		row = saved;
865 	}
866 
867 
868 	  /*
869 	   * Work out where the line lies in the field in relation to
870 	   * the cursor_ypos.  First count the rows from the start of
871 	   * the field until we hit the row we just worked on.
872 	   */
873 	saved = field->start_line;
874 	count = 0;
875 	while (saved->next != NULL) {
876 		if (saved == row)
877 			break;
878 		count++;
879 		saved = saved->next;
880 	}
881 
882 	  /* now check if we need to adjust cursor_ypos */
883 	if (field->cursor_ypos > count) {
884 		field->cursor_ypos--;
885 	}
886 
887 	field->row_count--;
888 	*rowp = row;
889 
890 	  /* wrap the field if required, if this fails undo the change */
891 	if ((direction == JOIN_NEXT) || (direction == JOIN_PREV)) {
892 		if (_formi_wrap_field(field, row) != E_OK) {
893 			return E_REQUEST_DENIED;
894 		}
895 	}
896 
897 	return E_OK;
898 }
899 
900 /*
901  * Split the line at the given position, if possible.  If hard_split is
902  * TRUE then split the line regardless of the position, otherwise don't
903  * split at the beginning of a line.
904  */
905 static int
906 split_line(FIELD *field, bool hard_split, unsigned pos,
907 	   _FORMI_FIELD_LINES **rowp)
908 {
909 	struct _formi_field_lines *new_line;
910 	char *newp;
911 	_FORMI_FIELD_LINES *row = *rowp;
912 #ifdef DEBUG
913 	short dbg_ok = FALSE;
914 #endif
915 
916 	  /* if asked to split right where the line already starts then
917 	   * just return - nothing to do unless we are appending a line
918 	   * to the buffer.
919 	   */
920 	if ((pos == 0) && (hard_split == FALSE))
921 		return E_OK;
922 
923 #ifdef DEBUG
924 	if (_formi_create_dbg_file() == E_OK) {
925 		fprintf(dbg, "split_line: splitting line at %d\n", pos);
926 		dbg_ok = TRUE;
927 	}
928 #endif
929 
930 	  /* Need an extra line struct, check free list first */
931 	if (field->free != NULL) {
932 		new_line = field->free;
933 		field->free = new_line->next;
934 		if (field->free != NULL)
935 			field->free->prev = NULL;
936 	} else {
937 		if ((new_line = (struct _formi_field_lines *)
938 		     malloc(sizeof(struct _formi_field_lines))) == NULL)
939 			return E_SYSTEM_ERROR;
940 		new_line->prev = NULL;
941 		new_line->next = NULL;
942 		new_line->allocated = 0;
943 		new_line->length = 0;
944 		new_line->expanded = 0;
945 		new_line->string = NULL;
946 		new_line->hard_ret = FALSE;
947 		new_line->tabs = NULL;
948 	}
949 
950 #ifdef DEBUG
951 	if (dbg_ok == TRUE) {
952 		fprintf(dbg,
953 	"split_line: enter: length = %d, expanded = %d\n",
954 			row->length, row->expanded);
955 	}
956 #endif
957 
958 	assert((row->length < INT_MAX) && (row->expanded < INT_MAX));
959 
960 
961 	  /* add new line to the row list */
962 	new_line->next = row->next;
963 	new_line->prev = row;
964 	row->next = new_line;
965 	if (new_line->next != NULL)
966 		new_line->next->prev = new_line;
967 
968 	new_line->length = row->length - pos;
969 	if (new_line->length >= new_line->allocated) {
970 		if ((newp = realloc(new_line->string,
971 				    (size_t) new_line->length + 1)) == NULL)
972 			return E_SYSTEM_ERROR;
973 		new_line->string = newp;
974 		new_line->allocated = new_line->length + 1;
975 	}
976 
977 	strcpy(new_line->string, &row->string[pos]);
978 
979 	row->length = pos;
980 	row->string[pos] = '\0';
981 
982 	if (row->length != 0)
983 		row->expanded = _formi_tab_expanded_length(row->string, 0,
984 							   row->length - 1);
985 	else
986 		row->expanded = 0;
987 	_formi_calculate_tabs(row);
988 
989 	if (new_line->length != 0)
990 		new_line->expanded =
991 			_formi_tab_expanded_length(new_line->string, 0,
992 						   new_line->length - 1);
993 	else
994 		new_line->expanded = 0;
995 
996 	_formi_calculate_tabs(new_line);
997 
998 	  /*
999 	   * If the given row was the current line then adjust the
1000 	   * current line pointer if necessary
1001 	   */
1002 	if ((field->cur_line == row) && (field->row_xpos >= pos)) {
1003 		field->cur_line = new_line;
1004 		field->row_xpos -= pos;
1005 		field->cursor_xpos =
1006 			_formi_tab_expanded_length(new_line->string, 0,
1007 						   field->row_xpos);
1008 		if (field->cursor_xpos > 0)
1009 			field->cursor_xpos--;
1010 
1011 		field->cursor_ypos++;
1012 		if (field->cursor_ypos >= field->rows) {
1013 			if (field->start_line->next != NULL) {
1014 				field->start_line = field->start_line->next;
1015 				field->cursor_ypos = field->rows - 1;
1016 			}
1017 			else
1018 				assert(field->start_line->next == NULL);
1019 		}
1020 	}
1021 
1022 	  /*
1023 	   * If the line split had a hard return then replace the
1024 	   * current line's hard return with a soft return and carry
1025 	   * the hard return onto the line after.
1026 	   */
1027 	if (row->hard_ret == TRUE) {
1028 		new_line->hard_ret = TRUE;
1029 		row->hard_ret = FALSE;
1030 	}
1031 
1032 	  /*
1033 	   * except where we are doing a hard split then the current
1034 	   * row must have a hard return on it too...
1035 	   */
1036 	if (hard_split == TRUE) {
1037 		row->hard_ret = TRUE;
1038 	}
1039 
1040 	assert(((row->expanded < INT_MAX) &&
1041 		(new_line->expanded < INT_MAX) &&
1042 		(row->length < INT_MAX) &&
1043 		(new_line->length < INT_MAX)));
1044 
1045 #ifdef DEBUG
1046 	if (dbg_ok == TRUE) {
1047 		fprintf(dbg, "split_line: exit: ");
1048 		fprintf(dbg, "row.length = %d, row.expanded = %d, ",
1049 			row->length, row->expanded);
1050 		fprintf(dbg,
1051 			"next_line.length = %d, next_line.expanded = %d, ",
1052 			new_line->length, new_line->expanded);
1053 		fprintf(dbg, "row_count = %d\n", field->row_count + 1);
1054 	}
1055 #endif
1056 
1057 	field->row_count++;
1058 	*rowp = new_line;
1059 
1060 	return E_OK;
1061 }
1062 
1063 /*
1064  * skip the blanks in the given string, start at the index start and
1065  * continue forward until either the end of the string or a non-blank
1066  * character is found.  Return the index of either the end of the string or
1067  * the first non-blank character.
1068  */
1069 unsigned
1070 _formi_skip_blanks(char *string, unsigned int start)
1071 {
1072 	unsigned int i;
1073 
1074 	i = start;
1075 
1076 	while ((string[i] != '\0') && isblank(string[i]))
1077 		i++;
1078 
1079 	return i;
1080 }
1081 
1082 /*
1083  * Skip the blanks in the string associated with the given row, pass back
1084  * the row and the offset at which the first non-blank is found.  If no
1085  * non-blank character is found then return the index to the last
1086  * character on the last line.
1087  */
1088 
1089 unsigned
1090 field_skip_blanks(unsigned int start, _FORMI_FIELD_LINES **rowp)
1091 {
1092 	unsigned int i;
1093 	_FORMI_FIELD_LINES *row, *last = NULL;
1094 
1095 	row = *rowp;
1096 	i = start;
1097 
1098 	do {
1099 		i = _formi_skip_blanks(&row->string[i], i);
1100 		if (!isblank(row->string[i])) {
1101 			last = row;
1102 			row = row->next;
1103 			  /*
1104 			   * don't reset if last line otherwise we will
1105 			   * not be at the end of the string.
1106 			   */
1107 			if (row != NULL)
1108 				i = 0;
1109 		} else
1110 			break;
1111 	}
1112 	while (row != NULL);
1113 
1114 	  /*
1115 	   * If we hit the end of the row list then point at the last row
1116 	   * otherwise we return the row we found the blank on.
1117 	   */
1118 	if (row == NULL)
1119 		*rowp = last;
1120 	else
1121 		*rowp = row;
1122 
1123 	return i;
1124 }
1125 
1126 /*
1127  * Return the index of the top left most field of the two given fields.
1128  */
1129 static int
1130 _formi_top_left(FORM *form, int a, int b)
1131 {
1132 	  /* lower row numbers always win here.... */
1133 	if (form->fields[a]->form_row < form->fields[b]->form_row)
1134 		return a;
1135 
1136 	if (form->fields[a]->form_row > form->fields[b]->form_row)
1137 		return b;
1138 
1139 	  /* rows must be equal, check columns */
1140 	if (form->fields[a]->form_col < form->fields[b]->form_col)
1141 		return a;
1142 
1143 	if (form->fields[a]->form_col > form->fields[b]->form_col)
1144 		return b;
1145 
1146 	  /* if we get here fields must be in exactly the same place, punt */
1147 	return a;
1148 }
1149 
1150 /*
1151  * Return the index to the field that is the bottom-right-most of the
1152  * two given fields.
1153  */
1154 static int
1155 _formi_bottom_right(FORM *form, int a, int b)
1156 {
1157 	  /* check the rows first, biggest row wins */
1158 	if (form->fields[a]->form_row > form->fields[b]->form_row)
1159 		return a;
1160 	if (form->fields[a]->form_row < form->fields[b]->form_row)
1161 		return b;
1162 
1163 	  /* rows must be equal, check cols, biggest wins */
1164 	if (form->fields[a]->form_col > form->fields[b]->form_col)
1165 		return a;
1166 	if (form->fields[a]->form_col < form->fields[b]->form_col)
1167 		return b;
1168 
1169 	  /* fields in the same place, punt */
1170 	return a;
1171 }
1172 
1173 /*
1174  * Find the end of the current word in the string str, starting at
1175  * offset - the end includes any trailing whitespace.  If the end of
1176  * the string is found before a new word then just return the offset
1177  * to the end of the string.  If do_join is TRUE then lines will be
1178  * joined (without wrapping) until either the end of the field or the
1179  * end of a word is found (whichever comes first).
1180  */
1181 static int
1182 find_eow(FIELD *cur, unsigned int offset, bool do_join,
1183 	 _FORMI_FIELD_LINES **rowp)
1184 {
1185 	int start;
1186 	_FORMI_FIELD_LINES *row;
1187 
1188 	row = *rowp;
1189 	start = offset;
1190 
1191 	do {
1192 		  /* first skip any non-whitespace */
1193 		while ((row->string[start] != '\0')
1194 		       && !isblank(row->string[start]))
1195 			start++;
1196 
1197 		  /* see if we hit the end of the string */
1198 		if (row->string[start] == '\0') {
1199 			if (do_join == TRUE) {
1200 				if (row->next == NULL)
1201 					return start;
1202 
1203 				if (_formi_join_line(cur, &row, JOIN_NEXT_NW)
1204 				    != E_OK)
1205 					return E_REQUEST_DENIED;
1206 			} else {
1207 				do {
1208 					if (row->next == NULL) {
1209 						*rowp = row;
1210 						return start;
1211 					} else {
1212 						row = row->next;
1213 						start = 0;
1214 					}
1215 				} while (row->length == 0);
1216 			}
1217 		}
1218 	} while (!isblank(row->string[start]));
1219 
1220 	do {
1221 		  /* otherwise skip the whitespace.... */
1222 		while ((row->string[start] != '\0')
1223 		       && isblank(row->string[start]))
1224 			start++;
1225 
1226 		if (row->string[start] == '\0') {
1227 			if (do_join == TRUE) {
1228 				if (row->next == NULL)
1229 					return start;
1230 
1231 				if (_formi_join_line(cur, &row, JOIN_NEXT_NW)
1232 				    != E_OK)
1233 					return E_REQUEST_DENIED;
1234 			} else {
1235 				do {
1236 					if (row->next == NULL) {
1237 						*rowp = row;
1238 						return start;
1239 					} else {
1240 						row = row->next;
1241 						start = 0;
1242 					}
1243 				} while (row->length == 0);
1244 			}
1245 		}
1246 	} while (isblank(row->string[start]));
1247 
1248 	*rowp = row;
1249 	return start;
1250 }
1251 
1252 /*
1253  * Find the beginning of the current word in the string str, starting
1254  * at offset.
1255  */
1256 static int
1257 find_sow(unsigned int offset, _FORMI_FIELD_LINES **rowp)
1258 {
1259 	int start;
1260 	char *str;
1261 	_FORMI_FIELD_LINES *row;
1262 
1263 	row = *rowp;
1264 	str = row->string;
1265 	start = offset;
1266 
1267 	do {
1268 		if (start > 0) {
1269 			if (isblank(str[start]) || isblank(str[start - 1])) {
1270 				if (isblank(str[start - 1]))
1271 					start--;
1272 				  /* skip the whitespace.... */
1273 				while ((start >= 0) && isblank(str[start]))
1274 					start--;
1275 			}
1276 		}
1277 
1278 		  /* see if we hit the start of the string */
1279 		if (start < 0) {
1280 			do {
1281 				if (row->prev == NULL) {
1282 					*rowp = row;
1283 					start = 0;
1284 					return start;
1285 				} else {
1286 					row = row->prev;
1287 					str = row->string;
1288 					if (row->length > 0)
1289 						start = row->length - 1;
1290 					else
1291 						start = 0;
1292 				}
1293 			} while (row->length == 0);
1294 		}
1295 	} while (isblank(row->string[start]));
1296 
1297 	  /* see if we hit the start of the string */
1298 	if (start < 0) {
1299 		*rowp = row;
1300 		return 0;
1301 	}
1302 
1303 	  /* now skip any non-whitespace */
1304 	do {
1305 		while ((start >= 0) && !isblank(str[start]))
1306 			start--;
1307 
1308 
1309 		if (start < 0) {
1310 			do {
1311 				if (row->prev == NULL) {
1312 					*rowp = row;
1313 					start = 0;
1314 					return start;
1315 				} else {
1316 					row = row->prev;
1317 					str = row->string;
1318 					if (row->length > 0)
1319 						start = row->length - 1;
1320 					else
1321 						start = 0;
1322 				}
1323 			} while (row->length == 0);
1324 		}
1325 	} while (!isblank(str[start]));
1326 
1327 	if (start > 0) {
1328 		start++; /* last loop has us pointing at a space, adjust */
1329 		if (start >= row->length) {
1330 			if (row->next != NULL) {
1331 				start = 0;
1332 				row = row->next;
1333 			} else {
1334 				start = row->length - 1;
1335 			}
1336 		}
1337 	}
1338 
1339 	if (start < 0)
1340 		start = 0;
1341 
1342 	*rowp = row;
1343 	return start;
1344 }
1345 
1346 /*
1347  * Scroll the field forward the given number of lines.
1348  */
1349 static void
1350 _formi_scroll_fwd(FIELD *field, unsigned int amt)
1351 {
1352 	unsigned int count;
1353 	_FORMI_FIELD_LINES *end_row;
1354 
1355 	end_row = field->start_line;
1356 	  /* walk the line structs forward to find the bottom of the field */
1357 	count = field->rows - 1;
1358 	while ((count > 0) && (end_row->next != NULL))
1359 	{
1360 		count--;
1361 		end_row = end_row->next;
1362 	}
1363 
1364 	  /* check if there are lines to scroll */
1365 	if ((count > 0) && (end_row->next == NULL))
1366 		return;
1367 
1368 	  /*
1369 	   * ok, lines to scroll - do this by walking both the start_line
1370 	   * and the end_row at the same time for amt lines, we stop when
1371 	   * either we have done the number of lines or end_row hits the
1372 	   * last line in the field.
1373 	   */
1374 	count = amt;
1375 	while ((count > 0) && (end_row->next != NULL)) {
1376 		count--;
1377 		field->start_line = field->start_line->next;
1378 		end_row = end_row->next;
1379 	}
1380 }
1381 
1382 /*
1383  * Scroll the field backward the given number of lines.
1384  */
1385 static void
1386 _formi_scroll_back(FIELD *field, unsigned int amt)
1387 {
1388 	unsigned int count;
1389 
1390 	  /* check for lines above */
1391 	if (field->start_line->prev == NULL)
1392 		return;
1393 
1394 	  /*
1395 	   * Backward scroll is easy, follow row struct chain backward until
1396 	   * the number of lines done or we reach the top of the field.
1397 	   */
1398 	count = amt;
1399 	while ((count > 0) && (field->start_line->prev != NULL)) {
1400 		count--;
1401 		field->start_line = field->start_line->prev;
1402 	}
1403 }
1404 
1405 /*
1406  * Scroll the field forward the given number of characters.
1407  */
1408 void
1409 _formi_hscroll_fwd(FIELD *field, _FORMI_FIELD_LINES *row, int unsigned amt)
1410 {
1411 	unsigned int end, scroll_amt, expanded;
1412 	_formi_tab_t *ts;
1413 
1414 
1415 	if ((row->tabs == NULL) || (row->tabs->in_use == FALSE)) {
1416 		  /* if the line has no tabs things are easy... */
1417 		end =  field->start_char + field->cols + amt - 1;
1418 		scroll_amt = amt;
1419 		if (end > row->length) {
1420 			end = row->length;
1421 			scroll_amt = end - field->start_char - field->cols + 1;
1422 		}
1423 	} else {
1424 		  /*
1425 		   * If there are tabs we need to add on the scroll amount,
1426 		   * find the last char position that will fit into
1427 		   * the field and finally fix up the start_char.  This
1428 		   * is a lot of work but handling the case where there
1429 		   * are not enough chars to scroll by amt is difficult.
1430 		   */
1431 		end = field->start_char + field->row_xpos + amt;
1432 		if (end >= row->length)
1433 			end = row->length - 1;
1434 		else {
1435 			expanded = _formi_tab_expanded_length(
1436 				row->string,
1437 				field->start_char + amt,
1438 				field->start_char + field->row_xpos + amt);
1439 			ts = row->tabs;
1440 			  /* skip tabs to the lhs of our starting point */
1441 			while ((ts != NULL) && (ts->in_use == TRUE)
1442 			       && (ts->pos < end))
1443 				ts = ts->fwd;
1444 
1445 			while ((expanded <= field->cols)
1446 			       && (end < row->length)) {
1447 				if (row->string[end] == '\t') {
1448 					assert((ts != NULL)
1449 					       && (ts->in_use == TRUE));
1450 					if (ts->pos == end) {
1451 						if ((expanded + ts->size)
1452 						    > field->cols)
1453 							break;
1454 						expanded += ts->size;
1455 						ts = ts->fwd;
1456 					}
1457 					else
1458 						assert(ts->pos == end);
1459 				} else
1460 					expanded++;
1461 				end++;
1462 			}
1463 		}
1464 
1465 		scroll_amt = tab_fit_window(field, end, field->cols);
1466 		if (scroll_amt < field->start_char)
1467 			scroll_amt = 1;
1468 		else
1469 			scroll_amt -= field->start_char;
1470 
1471 		scroll_amt = min(scroll_amt, amt);
1472 	}
1473 
1474 	field->start_char += scroll_amt;
1475 	field->cursor_xpos =
1476 		_formi_tab_expanded_length(row->string,
1477 					   field->start_char,
1478 					   field->row_xpos
1479 					   + field->start_char) - 1;
1480 
1481 }
1482 
1483 /*
1484  * Scroll the field backward the given number of characters.
1485  */
1486 void
1487 _formi_hscroll_back(FIELD *field, _FORMI_FIELD_LINES *row, unsigned int amt)
1488 {
1489 	field->start_char -= min(field->start_char, amt);
1490 	field->cursor_xpos =
1491 		_formi_tab_expanded_length(row->string, field->start_char,
1492 					   field->row_xpos
1493 					   + field->start_char) - 1;
1494 	if (field->cursor_xpos >= field->cols) {
1495 		field->row_xpos = 0;
1496 		field->cursor_xpos = 0;
1497 	}
1498 }
1499 
1500 /*
1501  * Find the different pages in the form fields and assign the form
1502  * page_starts array with the information to find them.
1503  */
1504 int
1505 _formi_find_pages(FORM *form)
1506 {
1507 	int i, cur_page = 0;
1508 
1509 	if ((form->page_starts = (_FORMI_PAGE_START *)
1510 	     malloc((form->max_page + 1) * sizeof(_FORMI_PAGE_START))) == NULL)
1511 		return E_SYSTEM_ERROR;
1512 
1513 	  /* initialise the page starts array */
1514 	memset(form->page_starts, 0,
1515 	       (form->max_page + 1) * sizeof(_FORMI_PAGE_START));
1516 
1517 	for (i =0; i < form->field_count; i++) {
1518 		if (form->fields[i]->page_break == 1)
1519 			cur_page++;
1520 		if (form->page_starts[cur_page].in_use == 0) {
1521 			form->page_starts[cur_page].in_use = 1;
1522 			form->page_starts[cur_page].first = i;
1523 			form->page_starts[cur_page].last = i;
1524 			form->page_starts[cur_page].top_left = i;
1525 			form->page_starts[cur_page].bottom_right = i;
1526 		} else {
1527 			form->page_starts[cur_page].last = i;
1528 			form->page_starts[cur_page].top_left =
1529 				_formi_top_left(form,
1530 						form->page_starts[cur_page].top_left,
1531 						i);
1532 			form->page_starts[cur_page].bottom_right =
1533 				_formi_bottom_right(form,
1534 						    form->page_starts[cur_page].bottom_right,
1535 						    i);
1536 		}
1537 	}
1538 
1539 	return E_OK;
1540 }
1541 
1542 /*
1543  * Completely redraw the field of the given form.
1544  */
1545 void
1546 _formi_redraw_field(FORM *form, int field)
1547 {
1548 	unsigned int pre, post, flen, slen, i, j, start, line;
1549 	unsigned int tab, cpos, len;
1550 	char *str, c;
1551 	FIELD *cur;
1552 	_FORMI_FIELD_LINES *row;
1553 #ifdef DEBUG
1554 	char buffer[100];
1555 #endif
1556 
1557 	cur = form->fields[field];
1558 	flen = cur->cols;
1559 	slen = 0;
1560 	start = 0;
1561 	line = 0;
1562 
1563 	for (row = cur->start_line; ((row != NULL) && (line < cur->rows));
1564 	     row = row->next, line++) {
1565 		wmove(form->scrwin, (int) (cur->form_row + line),
1566 		      (int) cur->form_col);
1567 		if ((cur->rows + cur->nrows) == 1) {
1568 			if ((cur->cols + cur->start_char) >= row->length)
1569 				len = row->length;
1570 			else
1571 				len = cur->cols + cur->start_char;
1572 			if (row->string != NULL)
1573 				slen = _formi_tab_expanded_length(
1574 					row->string, cur->start_char, len);
1575 			else
1576 				slen = 0;
1577 
1578 			if (slen > cur->cols)
1579 				slen = cur->cols;
1580 			slen += cur->start_char;
1581 		} else
1582 			slen = row->expanded;
1583 
1584 		if ((cur->opts & O_STATIC) == O_STATIC) {
1585 			switch (cur->justification) {
1586 			case JUSTIFY_RIGHT:
1587 				post = 0;
1588 				if (flen < slen)
1589 					pre = 0;
1590 				else
1591 					pre = flen - slen;
1592 				break;
1593 
1594 			case JUSTIFY_CENTER:
1595 				if (flen < slen) {
1596 					pre = 0;
1597 					post = 0;
1598 				} else {
1599 					pre = flen - slen;
1600 					post = pre = pre / 2;
1601 					  /* get padding right if
1602 					     centring is not even */
1603 					if ((post + pre + slen) < flen)
1604 						post++;
1605 				}
1606 				break;
1607 
1608 			case NO_JUSTIFICATION:
1609 			case JUSTIFY_LEFT:
1610 			default:
1611 				pre = 0;
1612 				if (flen <= slen)
1613 					post = 0;
1614 				else {
1615 					post = flen - slen;
1616 					if (post > flen)
1617 						post = flen;
1618 				}
1619 				break;
1620 			}
1621 		} else {
1622 			  /* dynamic fields are not justified */
1623 			pre = 0;
1624 			if (flen <= slen)
1625 				post = 0;
1626 			else {
1627 				post = flen - slen;
1628 				if (post > flen)
1629 					post = flen;
1630 			}
1631 
1632 			  /* but they do scroll.... */
1633 
1634 			if (pre > cur->start_char - start)
1635 				pre = pre - cur->start_char + start;
1636 			else
1637 				pre = 0;
1638 
1639 			if (slen > cur->start_char) {
1640 				slen -= cur->start_char;
1641 				if (slen > flen)
1642 					post = 0;
1643 				else
1644 					post = flen - slen;
1645 
1646 				if (post > flen)
1647 					post = flen;
1648 			} else {
1649 				slen = 0;
1650 				post = flen - pre;
1651 			}
1652 		}
1653 
1654 		if (form->cur_field == field)
1655 			wattrset(form->scrwin, cur->fore);
1656 		else
1657 			wattrset(form->scrwin, cur->back);
1658 
1659 		str = &row->string[cur->start_char];
1660 
1661 #ifdef DEBUG
1662 		if (_formi_create_dbg_file() == E_OK) {
1663 			fprintf(dbg,
1664   "redraw_field: start=%d, pre=%d, slen=%d, flen=%d, post=%d, start_char=%d\n",
1665 				start, pre, slen, flen, post, cur->start_char);
1666 			if (str != NULL) {
1667 				if (row->expanded != 0) {
1668 					strncpy(buffer, str, flen);
1669 				} else {
1670 					strcpy(buffer, "(empty)");
1671 				}
1672 			} else {
1673 				strcpy(buffer, "(null)");
1674 			}
1675 			buffer[flen] = '\0';
1676 			fprintf(dbg, "redraw_field: %s\n", buffer);
1677 		}
1678 #endif
1679 
1680 		for (i = start + cur->start_char; i < pre; i++)
1681 			waddch(form->scrwin, cur->pad);
1682 
1683 #ifdef DEBUG
1684 		fprintf(dbg, "redraw_field: will add %d chars\n",
1685 			min(slen, flen));
1686 #endif
1687 		for (i = 0, cpos = cur->start_char; i < min(slen, flen);
1688 		     i++, str++, cpos++)
1689 		{
1690 			c = *str;
1691 			tab = 0; /* just to shut gcc up */
1692 #ifdef DEBUG
1693 			fprintf(dbg, "adding char str[%d]=%c\n",
1694 				cpos + cur->start_char,	c);
1695 #endif
1696 			if (((cur->opts & O_PUBLIC) != O_PUBLIC)) {
1697 				if (c == '\t')
1698 					tab = add_tab(form, row, cpos,
1699 						      cur->pad);
1700 				else
1701 					waddch(form->scrwin, cur->pad);
1702 			} else if ((cur->opts & O_VISIBLE) == O_VISIBLE) {
1703 				if (c == '\t')
1704 					tab = add_tab(form, row, cpos, ' ');
1705 				else
1706 					waddch(form->scrwin, c);
1707 			} else {
1708 				if (c == '\t')
1709 					tab = add_tab(form, row, cpos, ' ');
1710 				else
1711 					waddch(form->scrwin, ' ');
1712 			}
1713 
1714 			  /*
1715 			   * If we have had a tab then skip forward
1716 			   * the requisite number of chars to keep
1717 			   * things in sync.
1718 			   */
1719 			if (c == '\t')
1720 				i += tab - 1;
1721 		}
1722 
1723 		for (i = 0; i < post; i++)
1724 			waddch(form->scrwin, cur->pad);
1725 	}
1726 
1727 	for (i = line; i < cur->rows; i++) {
1728 		wmove(form->scrwin, (int) (cur->form_row + i),
1729 		      (int) cur->form_col);
1730 
1731 		if (form->cur_field == field)
1732 			wattrset(form->scrwin, cur->fore);
1733 		else
1734 			wattrset(form->scrwin, cur->back);
1735 
1736 		for (j = 0; j < cur->cols; j++) {
1737 			waddch(form->scrwin, cur->pad);
1738 		}
1739 	}
1740 
1741 	wattrset(form->scrwin, cur->back);
1742 	return;
1743 }
1744 
1745 /*
1746  * Add the correct number of the given character to simulate a tab
1747  * in the field.
1748  */
1749 static int
1750 add_tab(FORM *form, _FORMI_FIELD_LINES *row, unsigned int i, char c)
1751 {
1752 	int j;
1753 	_formi_tab_t *ts = row->tabs;
1754 
1755 	while ((ts != NULL) && (ts->pos != i))
1756 		ts = ts->fwd;
1757 
1758 	assert(ts != NULL);
1759 
1760 	for (j = 0; j < ts->size; j++)
1761 		waddch(form->scrwin, c);
1762 
1763 	return ts->size;
1764 }
1765 
1766 
1767 /*
1768  * Display the fields attached to the form that are on the current page
1769  * on the screen.
1770  *
1771  */
1772 int
1773 _formi_draw_page(FORM *form)
1774 {
1775 	int i;
1776 
1777 	if (form->page_starts[form->page].in_use == 0)
1778 		return E_BAD_ARGUMENT;
1779 
1780 	wclear(form->scrwin);
1781 
1782 	for (i = form->page_starts[form->page].first;
1783 	     i <= form->page_starts[form->page].last; i++)
1784 		_formi_redraw_field(form, i);
1785 
1786 	return E_OK;
1787 }
1788 
1789 /*
1790  * Add the character c at the position pos in buffer 0 of the given field
1791  */
1792 int
1793 _formi_add_char(FIELD *field, unsigned int pos, char c)
1794 {
1795 	char *new, old_c;
1796 	unsigned int new_size;
1797 	int status;
1798 	_FORMI_FIELD_LINES *row, *temp, *next_temp;
1799 
1800 	row = field->cur_line;
1801 
1802 	  /*
1803 	   * If buffer has not had a string before, set it to a blank
1804 	   * string.  Everything should flow from there....
1805 	   */
1806 	if (row->string == NULL) {
1807 		if ((row->string = (char *) malloc((size_t)INITIAL_LINE_ALLOC))
1808 		    == NULL)
1809 			return E_SYSTEM_ERROR;
1810 		row->string[0] = '\0';
1811 		row->allocated = INITIAL_LINE_ALLOC;
1812 		row->length = 0;
1813 		row->expanded = 0;
1814 	}
1815 
1816 	if (_formi_validate_char(field, c) != E_OK) {
1817 #ifdef DEBUG
1818 		fprintf(dbg, "add_char: char %c failed char validation\n", c);
1819 #endif
1820 		return E_INVALID_FIELD;
1821 	}
1822 
1823 	if ((c == '\t') && (field->cols <= 8)) {
1824 #ifdef DEBUG
1825 		fprintf(dbg, "add_char: field too small for a tab\n");
1826 #endif
1827 		return E_NO_ROOM;
1828 	}
1829 
1830 #ifdef DEBUG
1831 	fprintf(dbg, "add_char: pos=%d, char=%c\n", pos, c);
1832 	fprintf(dbg, "add_char enter: xpos=%d, row_pos=%d, start=%d\n",
1833 		field->cursor_xpos, field->row_xpos, field->start_char);
1834 	fprintf(dbg, "add_char enter: length=%d(%d), allocated=%d\n",
1835 		row->expanded, row->length, row->allocated);
1836 	fprintf(dbg, "add_char enter: %s\n", row->string);
1837 	fprintf(dbg, "add_char enter: buf0_status=%d\n", field->buf0_status);
1838 #endif
1839 	if (((field->opts & O_BLANK) == O_BLANK) &&
1840 	    (field->buf0_status == FALSE) &&
1841 	    ((field->row_xpos + field->start_char) == 0)) {
1842 		row = field->lines;
1843 		if (row->next != NULL) {
1844 			  /* shift all but one line structs to free list */
1845 			temp = row->next;
1846 			do {
1847 				next_temp = temp->next;
1848 				add_to_free(field, temp);
1849 				temp = next_temp;
1850 			} while (temp != NULL);
1851 		}
1852 
1853 		row->length = 0;
1854 		row->string[0] = '\0';
1855 		pos = 0;
1856 		field->start_char = 0;
1857 		field->start_line = row;
1858 		field->cur_line = row;
1859 		field->row_count = 1;
1860 		field->row_xpos = 0;
1861 		field->cursor_ypos = 0;
1862 		row->expanded = 0;
1863 		row->length = 0;
1864 		_formi_init_field_xpos(field);
1865 	}
1866 
1867 
1868 	if ((field->overlay == 0)
1869 	    || ((field->overlay == 1) && (pos >= row->length))) {
1870 		  /* first check if the field can have more chars...*/
1871 		if (check_field_size(field) == FALSE)
1872 			return E_REQUEST_DENIED;
1873 
1874 		if (row->length + 2
1875 		    >= row->allocated) {
1876 			new_size = row->allocated + 16 - (row->allocated % 16);
1877 			if ((new = (char *) realloc(row->string,
1878 						  (size_t) new_size )) == NULL)
1879 				return E_SYSTEM_ERROR;
1880 			row->allocated = new_size;
1881 			row->string = new;
1882 		}
1883 	}
1884 
1885 	if ((field->overlay == 0) && (row->length > pos)) {
1886 		bcopy(&row->string[pos], &row->string[pos + 1],
1887 		      (size_t) (row->length - pos + 1));
1888 	}
1889 
1890 	old_c = row->string[pos];
1891 	row->string[pos] = c;
1892 	if (pos >= row->length) {
1893 		  /* make sure the string is terminated if we are at the
1894 		   * end of the string, the terminator would be missing
1895 		   * if we are are at the end of the field.
1896 		   */
1897 		row->string[pos + 1] = '\0';
1898 	}
1899 
1900 	  /* only increment the length if we are inserting characters
1901 	   * OR if we are at the end of the field in overlay mode.
1902 	   */
1903 	if ((field->overlay == 0)
1904 	    || ((field->overlay == 1) && (pos >= row->length))) {
1905 		row->length++;
1906 	}
1907 
1908 	_formi_calculate_tabs(row);
1909 	row->expanded = _formi_tab_expanded_length(row->string, 0,
1910 						   row->length - 1);
1911 
1912 	  /* wrap the field, if needed */
1913 	status = _formi_wrap_field(field, row);
1914 
1915 	row = field->cur_line;
1916 	pos = field->row_xpos;
1917 
1918 	  /*
1919 	   * check the wrap worked or that we have not exceeded the
1920 	   * max field size - this can happen if the field is re-wrapped
1921 	   * and the row count is increased past the set limit.
1922 	   */
1923 	if ((status != E_OK) || (check_field_size(field) == FALSE)) {
1924 		if ((field->overlay == 0)
1925 		    || ((field->overlay == 1)
1926 			&& (pos >= (row->length - 1) /*XXXX- append check???*/))) {
1927 			  /*
1928 			   * wrap failed for some reason, back out the
1929 			   * char insert
1930 			   */
1931 			bcopy(&row->string[pos + 1], &row->string[pos],
1932 			      (size_t) (row->length - pos));
1933 			row->length--;
1934 			if (pos > 0)
1935 				pos--;
1936 		} else if (field->overlay == 1) {
1937 			  /* back out character overlay */
1938 			row->string[pos] = old_c;
1939 		}
1940 
1941 		_formi_calculate_tabs(row);
1942 
1943 		_formi_wrap_field(field, row);
1944 		  /*
1945 		   * If we are here then either the status is bad or we
1946 		   * simply ran out of room.  If the status is E_OK then
1947 		   * we ran out of room, let the form driver know this.
1948 		   */
1949 		if (status == E_OK)
1950 			status = E_REQUEST_DENIED;
1951 
1952 	} else {
1953 		field->buf0_status = TRUE;
1954 		field->row_xpos++;
1955 		if ((field->rows + field->nrows) == 1) {
1956 			status = _formi_set_cursor_xpos(field, FALSE);
1957 		} else {
1958 			field->cursor_xpos =
1959 				_formi_tab_expanded_length(
1960 					row->string, 0,	field->row_xpos - 1);
1961 
1962 			  /*
1963 			   * Annoying corner case - if we are right in
1964 			   * the bottom right corner of the field we
1965 			   * need to scroll the field one line so the
1966 			   * cursor is positioned correctly in the
1967 			   * field.
1968 			   */
1969 			if ((field->cursor_xpos >= field->cols) &&
1970 			    (field->cursor_ypos == (field->rows - 1))) {
1971 				field->cursor_ypos--;
1972 				field->start_line = field->start_line->next;
1973 			}
1974 		}
1975 	}
1976 
1977 	assert((field->cursor_xpos <= field->cols)
1978 	       && (field->cursor_ypos < 400000));
1979 
1980 #ifdef DEBUG
1981 	fprintf(dbg, "add_char exit: xpos=%d, row_pos=%d, start=%d\n",
1982 		field->cursor_xpos, field->row_xpos, field->start_char);
1983 	fprintf(dbg, "add_char_exit: length=%d(%d), allocated=%d\n",
1984 		row->expanded, row->length, row->allocated);
1985 	fprintf(dbg, "add_char exit: ypos=%d, start_line=%p\n",
1986 		field->cursor_ypos, field->start_line);
1987 	fprintf(dbg,"add_char exit: %s\n", row->string);
1988 	fprintf(dbg, "add_char exit: buf0_status=%d\n", field->buf0_status);
1989 	fprintf(dbg, "add_char exit: status = %s\n",
1990 		(status == E_OK)? "OK" : "FAILED");
1991 #endif
1992 	return status;
1993 }
1994 
1995 /*
1996  * Set the position of the cursor on the screen in the row depending on
1997  * where the current position in the string is and the justification
1998  * that is to be applied to the field.  Justification is only applied
1999  * to single row, static fields.
2000  */
2001 static int
2002 _formi_set_cursor_xpos(FIELD *field, int noscroll)
2003 {
2004 	int just, pos;
2005 
2006 	just = field->justification;
2007 	pos = field->start_char + field->row_xpos;
2008 
2009 #ifdef DEBUG
2010 	fprintf(dbg,
2011 	  "cursor_xpos enter: pos %d, start_char %d, row_xpos %d, xpos %d\n",
2012 		pos, field->start_char, field->row_xpos, field->cursor_xpos);
2013 #endif
2014 
2015 	  /*
2016 	   * make sure we apply the correct justification to non-static
2017 	   * fields.
2018 	   */
2019 	if (((field->rows + field->nrows) != 1) ||
2020 	    ((field->opts & O_STATIC) != O_STATIC))
2021 		just = JUSTIFY_LEFT;
2022 
2023 	switch (just) {
2024 	case JUSTIFY_RIGHT:
2025 		field->cursor_xpos = field->cols - 1
2026 			- _formi_tab_expanded_length(
2027 				field->cur_line->string, 0,
2028 				field->cur_line->length - 1)
2029 			+ _formi_tab_expanded_length(
2030 				field->cur_line->string, 0,
2031 				field->row_xpos);
2032 		break;
2033 
2034 	case JUSTIFY_CENTER:
2035 		field->cursor_xpos = ((field->cols - 1)
2036 			- _formi_tab_expanded_length(
2037 				field->cur_line->string, 0,
2038 				field->cur_line->length - 1) + 1) / 2
2039 			+ _formi_tab_expanded_length(field->cur_line->string,
2040 						     0, field->row_xpos);
2041 
2042 		if (field->cursor_xpos > (field->cols - 1))
2043 			field->cursor_xpos = (field->cols - 1);
2044 		break;
2045 
2046 	default:
2047 		field->cursor_xpos = _formi_tab_expanded_length(
2048 			field->cur_line->string,
2049 			field->start_char,
2050 			field->row_xpos	+ field->start_char);
2051 		if ((field->cursor_xpos <= (field->cols - 1)) &&
2052 		    ((field->start_char + field->row_xpos)
2053 		     < field->cur_line->length))
2054 			field->cursor_xpos--;
2055 
2056 		if (field->cursor_xpos > (field->cols - 1)) {
2057 			if ((field->opts & O_STATIC) == O_STATIC) {
2058 				field->start_char = 0;
2059 
2060 				if (field->row_xpos
2061 				    == (field->cur_line->length - 1)) {
2062 					field->cursor_xpos = field->cols - 1;
2063 				} else {
2064 					field->cursor_xpos =
2065 						_formi_tab_expanded_length(
2066 						  field->cur_line->string,
2067 						  field->start_char,
2068 						  field->row_xpos
2069 						    + field->start_char
2070 						  - 1) - 1;
2071 				}
2072 			} else {
2073 				if (noscroll == FALSE) {
2074 					field->start_char =
2075 						tab_fit_window(
2076 							field,
2077 							field->start_char
2078 							+ field->row_xpos,
2079 							field->cols);
2080 					field->row_xpos = pos
2081 						- field->start_char;
2082 					field->cursor_xpos =
2083 						_formi_tab_expanded_length(
2084 						   field->cur_line->string,
2085 						   field->start_char,
2086 						   field->row_xpos
2087 						      + field->start_char - 1);
2088 				} else {
2089 					field->cursor_xpos = (field->cols - 1);
2090 				}
2091 			}
2092 
2093 		}
2094 		break;
2095 	}
2096 
2097 #ifdef DEBUG
2098 	fprintf(dbg,
2099 	  "cursor_xpos exit: pos %d, start_char %d, row_xpos %d, xpos %d\n",
2100 		pos, field->start_char, field->row_xpos, field->cursor_xpos);
2101 #endif
2102 	return E_OK;
2103 }
2104 
2105 /*
2106  * Manipulate the text in a field, this takes the given form and performs
2107  * the passed driver command on the current text field.  Returns 1 if the
2108  * text field was modified.
2109  */
2110 int
2111 _formi_manipulate_field(FORM *form, int c)
2112 {
2113 	FIELD *cur;
2114 	char *str, saved;
2115 	unsigned int start, end, pos, status, old_count, size;
2116 	unsigned int old_xpos, old_row_pos;
2117 	int len, wb;
2118 	bool eat_char;
2119 	_FORMI_FIELD_LINES *row, *rs;
2120 
2121 	cur = form->fields[form->cur_field];
2122 	if (cur->cur_line->string == NULL)
2123 		return E_REQUEST_DENIED;
2124 
2125 #ifdef DEBUG
2126 	fprintf(dbg, "entry: request is REQ_%s\n", reqs[c - REQ_MIN_REQUEST]);
2127 	fprintf(dbg,
2128 	"entry: xpos=%d, row_pos=%d, start_char=%d, length=%d, allocated=%d\n",
2129 		cur->cursor_xpos, cur->row_xpos, cur->start_char,
2130 		cur->cur_line->length,	cur->cur_line->allocated);
2131 	fprintf(dbg, "entry: start_line=%p, ypos=%d\n", cur->start_line,
2132 		cur->cursor_ypos);
2133 	fprintf(dbg, "entry: string=");
2134 	if (cur->cur_line->string == NULL)
2135 		fprintf(dbg, "(null)\n");
2136 	else
2137 		fprintf(dbg, "\"%s\"\n", cur->cur_line->string);
2138 #endif
2139 
2140 	  /* Cannot manipulate a null string! */
2141 	if (cur->cur_line->string == NULL)
2142 		return E_REQUEST_DENIED;
2143 
2144 	saved = '\0';
2145 	row = cur->cur_line;
2146 
2147 	switch (c) {
2148 	case REQ_RIGHT_CHAR:
2149 		  /*
2150 		   * The right_char request performs the same function
2151 		   * as the next_char request except that the cursor is
2152 		   * not wrapped if it is at the end of the line, so
2153 		   * check if the cursor is at the end of the line and
2154 		   * deny the request otherwise just fall through to
2155 		   * the next_char request handler.
2156 		   */
2157 		if (cur->cursor_xpos >= cur->cols - 1)
2158 			return E_REQUEST_DENIED;
2159 
2160 		  /* FALLTHRU */
2161 
2162 	case REQ_NEXT_CHAR:
2163 		  /* for a dynamic field allow an offset of one more
2164 		   * char so we can insert chars after end of string.
2165 		   * Static fields cannot do this so deny request if
2166 		   * cursor is at the end of the field.
2167 		   */
2168 		if (((cur->opts & O_STATIC) == O_STATIC) &&
2169 		    (cur->row_xpos == cur->cols - 1) &&
2170 		    ((cur->rows + cur->nrows) == 1))
2171 			return E_REQUEST_DENIED;
2172 
2173 		if (((cur->rows + cur->nrows) == 1) &&
2174 		    (cur->row_xpos + cur->start_char + 1) > row->length)
2175 			return E_REQUEST_DENIED;
2176 
2177 		if ((cur->rows + cur->nrows) == 1) {
2178 			cur->row_xpos++;
2179 			_formi_set_cursor_xpos(cur, (c == REQ_RIGHT_CHAR));
2180 		} else {
2181 			if (cur->cursor_xpos >= (row->expanded - 1)) {
2182 				if ((row->next == NULL) ||
2183 				    (c == REQ_RIGHT_CHAR))
2184 					return E_REQUEST_DENIED;
2185 
2186 				cur->cursor_xpos = 0;
2187 				cur->row_xpos = 0;
2188 				cur->cur_line = cur->cur_line->next;
2189 				if (cur->cursor_ypos == (cur->rows - 1))
2190 					cur->start_line =
2191 						cur->start_line->next;
2192 				else
2193 					cur->cursor_ypos++;
2194 			} else {
2195 				old_xpos = cur->cursor_xpos;
2196 				old_row_pos = cur->row_xpos;
2197 				if (row->string[cur->row_xpos] == '\t')
2198 					cur->cursor_xpos += tab_size(row,
2199 							cur->row_xpos);
2200 				else
2201 					cur->cursor_xpos++;
2202 				cur->row_xpos++;
2203 				if (cur->cursor_xpos
2204 				    >= row->expanded) {
2205 					if ((row->next == NULL) ||
2206 					    (c == REQ_RIGHT_CHAR)) {
2207 						cur->cursor_xpos = old_xpos;
2208 						cur->row_xpos = old_row_pos;
2209 						return E_REQUEST_DENIED;
2210 					}
2211 
2212 					cur->cursor_xpos = 0;
2213 					cur->row_xpos = 0;
2214 					cur->cur_line = cur->cur_line->next;
2215 					if (cur->cursor_ypos
2216 					    == (cur->rows - 1))
2217 						cur->start_line =
2218 							cur->start_line->next;
2219 					else
2220 						cur->cursor_ypos++;
2221 				}
2222 			}
2223 		}
2224 
2225 		break;
2226 
2227 	case REQ_LEFT_CHAR:
2228 		  /*
2229 		   * The behaviour of left_char is the same as prev_char
2230 		   * except that the cursor will not wrap if it has
2231 		   * reached the LHS of the field, so just check this
2232 		   * and fall through if we are not at the LHS.
2233 		   */
2234 		if (cur->cursor_xpos == 0)
2235 			return E_REQUEST_DENIED;
2236 
2237 		  /* FALLTHRU */
2238 	case REQ_PREV_CHAR:
2239 		if ((cur->rows + cur->nrows) == 1) {
2240 			if (cur->row_xpos == 0) {
2241 				if (cur->start_char > 0)
2242 					cur->start_char--;
2243 				else
2244 					return E_REQUEST_DENIED;
2245 			} else {
2246 				cur->row_xpos--;
2247 				_formi_set_cursor_xpos(cur, FALSE);
2248 			}
2249 		} else {
2250 			if ((cur->cursor_xpos == 0) &&
2251 			    (cur->cursor_ypos == 0) &&
2252 			    (cur->start_line->prev == NULL))
2253 				return E_REQUEST_DENIED;
2254 
2255 			pos = cur->row_xpos;
2256 			if (cur->cursor_xpos > 0) {
2257 				if (row->string[pos] == '\t') {
2258 					size = tab_size(row, pos);
2259 					if (size > cur->cursor_xpos) {
2260 						cur->cursor_xpos = 0;
2261 						cur->row_xpos = 0;
2262 					} else {
2263 						cur->row_xpos--;
2264 						cur->cursor_xpos -= size;
2265 					}
2266 				} else {
2267 					cur->cursor_xpos--;
2268 					cur->row_xpos--;
2269 				}
2270 			} else {
2271 				cur->cur_line = cur->cur_line->prev;
2272 				if (cur->cursor_ypos > 0)
2273 					cur->cursor_ypos--;
2274 				else
2275 					cur->start_line =
2276 						cur->start_line->prev;
2277 				row = cur->cur_line;
2278 				if (row->expanded > 0) {
2279 					cur->cursor_xpos = row->expanded - 1;
2280 				} else {
2281 					cur->cursor_xpos = 0;
2282 				}
2283 
2284 				if (row->length > 0)
2285 					cur->row_xpos = row->length - 1;
2286 				else
2287 					cur->row_xpos = 0;
2288 			}
2289 		}
2290 
2291 		break;
2292 
2293 	case REQ_DOWN_CHAR:
2294 		  /*
2295 		   * The down_char request has the same functionality as
2296 		   * the next_line request excepting that the field is not
2297 		   * scrolled if the cursor is at the bottom of the field.
2298 		   * Check to see if the cursor is at the bottom of the field
2299 		   * and if it is then deny the request otherwise fall
2300 		   * through to the next_line handler.
2301 		   */
2302 		if (cur->cursor_ypos >= cur->rows - 1)
2303 			return E_REQUEST_DENIED;
2304 
2305 		  /* FALLTHRU */
2306 
2307 	case REQ_NEXT_LINE:
2308 		if ((row->next == NULL) || (cur->cur_line->next == NULL))
2309 			return E_REQUEST_DENIED;
2310 
2311 		cur->cur_line = cur->cur_line->next;
2312 		if ((cur->cursor_ypos + 1) >= cur->rows) {
2313 			cur->start_line = cur->start_line->next;
2314 		} else
2315 			cur->cursor_ypos++;
2316 		row = cur->cur_line;
2317 
2318 		if (row->length == 0) {
2319 			cur->row_xpos = 0;
2320 			cur->cursor_xpos = 0;
2321 		} else {
2322 			if (cur->cursor_xpos > (row->expanded - 1))
2323 				cur->cursor_xpos = row->expanded - 1;
2324 
2325 			cur->row_xpos =	tab_fit_len(row, cur->cursor_xpos + 1);
2326 			if (cur->row_xpos == 0)
2327 				cur->cursor_xpos = 0;
2328 			else
2329 				cur->cursor_xpos =
2330 					_formi_tab_expanded_length(
2331 						row->string, 0, cur->row_xpos);
2332 			if (cur->cursor_xpos > 0)
2333 				cur->cursor_xpos--;
2334 		}
2335 		break;
2336 
2337 	case REQ_UP_CHAR:
2338 		  /*
2339 		   * The up_char request has the same functionality as
2340 		   * the prev_line request excepting the field is not
2341 		   * scrolled, check if the cursor is at the top of the
2342 		   * field, if it is deny the request otherwise fall
2343 		   * through to the prev_line handler.
2344 		   */
2345 		if (cur->cursor_ypos == 0)
2346 			return E_REQUEST_DENIED;
2347 
2348 		  /* FALLTHRU */
2349 
2350 	case REQ_PREV_LINE:
2351 		if (cur->cur_line->prev == NULL)
2352 			return E_REQUEST_DENIED;
2353 
2354 		if (cur->cursor_ypos == 0) {
2355 			if (cur->start_line->prev == NULL)
2356 				return E_REQUEST_DENIED;
2357 			cur->start_line = cur->start_line->prev;
2358 		} else
2359 			cur->cursor_ypos--;
2360 
2361 		cur->cur_line = cur->cur_line->prev;
2362 		row = cur->cur_line;
2363 
2364 		if (row->length == 0) {
2365 			cur->row_xpos = 0;
2366 			cur->cursor_xpos = 0;
2367 		} else {
2368 			if (cur->cursor_xpos > (row->expanded - 1))
2369 				cur->cursor_xpos = row->expanded - 1;
2370 
2371 			cur->row_xpos =	tab_fit_len(row, cur->cursor_xpos + 1);
2372 			cur->cursor_xpos =
2373 				_formi_tab_expanded_length(row->string,
2374 							   0, cur->row_xpos);
2375 			if (cur->cursor_xpos > 0)
2376 				cur->cursor_xpos--;
2377 		}
2378 		break;
2379 
2380 	case REQ_NEXT_WORD:
2381 		start = cur->row_xpos + cur->start_char;
2382 		str = row->string;
2383 
2384 		wb = find_eow(cur, start, FALSE, &row);
2385 		if (wb < 0)
2386 			return wb;
2387 
2388 		start = wb;
2389 		  /* check if we hit the end */
2390 		if (str[start] == '\0')
2391 			return E_REQUEST_DENIED;
2392 
2393 		  /* otherwise we must have found the start of a word...*/
2394 		if ((cur->rows + cur->nrows) == 1) {
2395 			  /* single line field */
2396 			size = _formi_tab_expanded_length(str,
2397 				cur->start_char, start);
2398 			if (size < cur->cols) {
2399 				cur->row_xpos = start - cur->start_char;
2400 			} else {
2401 				cur->start_char = start;
2402 				cur->row_xpos = 0;
2403 			}
2404 			_formi_set_cursor_xpos(cur, FALSE);
2405 		} else {
2406 			  /* multiline field */
2407 			cur->cur_line = row;
2408 			adjust_ypos(cur, row);
2409 
2410 			cur->row_xpos = start;
2411 			cur->cursor_xpos =
2412 				_formi_tab_expanded_length(
2413 					row->string, 0, cur->row_xpos) - 1;
2414 		}
2415 		break;
2416 
2417 	case REQ_PREV_WORD:
2418 		start = cur->start_char + cur->row_xpos;
2419 		if (cur->start_char > 0)
2420 			start--;
2421 
2422 		if ((start == 0) && (row->prev == NULL))
2423 			return E_REQUEST_DENIED;
2424 
2425 		if (start == 0) {
2426 			row = row->prev;
2427 			if (row->length > 0)
2428 				start = row->length - 1;
2429 			else
2430 				start = 0;
2431 		}
2432 
2433 		str = row->string;
2434 
2435 		start = find_sow(start, &row);
2436 
2437 		if ((cur->rows + cur->nrows) == 1) {
2438 			  /* single line field */
2439 			size = _formi_tab_expanded_length(str,
2440 				cur->start_char, start);
2441 
2442 			if (start > cur->start_char) {
2443 				cur->row_xpos = start - cur->start_char;
2444 			} else {
2445 				cur->start_char = start;
2446 				cur->row_xpos = 0;
2447 			}
2448 			_formi_set_cursor_xpos(cur, FALSE);
2449 		} else {
2450 			  /* multiline field */
2451 			cur->cur_line = row;
2452 			adjust_ypos(cur, row);
2453 			cur->row_xpos = start;
2454 			cur->cursor_xpos =
2455 				_formi_tab_expanded_length(
2456 					row->string, 0,
2457 					cur->row_xpos) - 1;
2458 		}
2459 
2460 		break;
2461 
2462 	case REQ_BEG_FIELD:
2463 		cur->start_char = 0;
2464 		while (cur->start_line->prev != NULL)
2465 			cur->start_line = cur->start_line->prev;
2466 		cur->cur_line = cur->start_line;
2467 		cur->row_xpos = 0;
2468 		_formi_init_field_xpos(cur);
2469 		cur->cursor_ypos = 0;
2470 		break;
2471 
2472 	case REQ_BEG_LINE:
2473 		cur->row_xpos = 0;
2474 		_formi_init_field_xpos(cur);
2475 		cur->start_char = 0;
2476 		break;
2477 
2478 	case REQ_END_FIELD:
2479 		while (cur->cur_line->next != NULL)
2480 			cur->cur_line = cur->cur_line->next;
2481 
2482 		if (cur->row_count > cur->rows) {
2483 			cur->start_line = cur->cur_line;
2484 			pos = cur->rows - 1;
2485 			while (pos > 0) {
2486 				cur->start_line = cur->start_line->prev;
2487 				pos--;
2488 			}
2489 			cur->cursor_ypos = cur->rows - 1;
2490 		} else {
2491 			cur->cursor_ypos = cur->row_count - 1;
2492 		}
2493 
2494 		  /* we fall through here deliberately, we are on the
2495 		   * correct row, now we need to get to the end of the
2496 		   * line.
2497 		   */
2498 		  /* FALLTHRU */
2499 
2500 	case REQ_END_LINE:
2501 		row = cur->cur_line;
2502 
2503 		if ((cur->rows + cur->nrows) == 1) {
2504 			if (row->expanded > cur->cols - 1) {
2505 				if ((cur->opts & O_STATIC) != O_STATIC) {
2506 					cur->start_char = tab_fit_window(
2507 						cur, row->length,
2508 						cur->cols) + 1;
2509 					cur->row_xpos = row->length
2510 						- cur->start_char;
2511 				} else {
2512 					cur->start_char = 0;
2513 					cur->row_xpos = cur->cols - 1;
2514 				}
2515 			} else {
2516 				cur->row_xpos = row->length + 1;
2517 				cur->start_char = 0;
2518 			}
2519 			_formi_set_cursor_xpos(cur, FALSE);
2520 		} else {
2521 			cur->row_xpos = row->length - 1;
2522 			cur->cursor_xpos = row->expanded - 1;
2523 			if (row->next == NULL) {
2524 				cur->row_xpos++;
2525 				cur->cursor_xpos++;
2526 			}
2527 		}
2528 		break;
2529 
2530 	case REQ_NEW_LINE:
2531 		start = cur->start_char	+ cur->row_xpos;
2532 		if ((status = split_line(cur, TRUE, start, &row)) != E_OK)
2533 			return status;
2534 		cur->cur_line->hard_ret = TRUE;
2535 		cur->cursor_xpos = 0;
2536 		cur->row_xpos = 0;
2537 		break;
2538 
2539 	case REQ_INS_CHAR:
2540 		if ((status = _formi_add_char(cur, cur->start_char
2541 					      + cur->row_xpos,
2542 					      cur->pad)) != E_OK)
2543 			return status;
2544 		break;
2545 
2546 	case REQ_INS_LINE:
2547 		if ((status = split_line(cur, TRUE, 0, &row)) != E_OK)
2548 			return status;
2549 		cur->cur_line->hard_ret = TRUE;
2550 		break;
2551 
2552 	case REQ_DEL_CHAR:
2553 		row = cur->cur_line;
2554 		start = cur->start_char + cur->row_xpos;
2555 		end = row->length - 1;
2556 		if ((start >= row->length) && (row->next == NULL))
2557 			return E_REQUEST_DENIED;
2558 
2559 		if ((start == row->length - 1) || (row->length == 0)) {
2560 			if ((cur->rows + cur->nrows) > 1) {
2561 				/*
2562 				 * Firstly, check if the current line has
2563 				 * a hard return.  In this case we just
2564 				 * want to "delete" the hard return and
2565 				 * re-wrap the field.  The hard return
2566 				 * does not occupy a character space in
2567 				 * the buffer but we must make it appear
2568 				 * like it does for a deletion.
2569 				 */
2570 				if (row->hard_ret == TRUE) {
2571 					row->hard_ret = FALSE;
2572 					if (_formi_join_line(cur, &row,
2573 							     JOIN_NEXT)
2574 					    != E_OK) {
2575 						row->hard_ret = TRUE;
2576 						return 0;
2577 					} else {
2578 						return 1;
2579 					}
2580 				}
2581 
2582 				/*
2583 				 * If we have more than one row, join the
2584 				 * next row to make things easier unless
2585 				 * we are at the end of the string, in
2586 				 * that case the join would fail but we
2587 				 * really want to delete the last char
2588 				 * in the field.
2589 				 */
2590 				if (row->next != NULL) {
2591 					if (_formi_join_line(cur, &row,
2592 							     JOIN_NEXT_NW)
2593 					    != E_OK) {
2594 						return E_REQUEST_DENIED;
2595 					}
2596 				}
2597 			}
2598 		}
2599 
2600 		saved = row->string[start];
2601 		bcopy(&row->string[start + 1], &row->string[start],
2602 		      (size_t) (end - start + 1));
2603 		row->string[end] = '\0';
2604 		row->length--;
2605 		if (row->length > 0)
2606 			row->expanded = _formi_tab_expanded_length(
2607 				row->string, 0, row->length - 1);
2608 		else
2609 			row->expanded = 0;
2610 
2611 		  /*
2612 		   * recalculate tabs for a single line field, multiline
2613 		   * fields will do this when the field is wrapped.
2614 		   */
2615 		if ((cur->rows + cur->nrows) == 1)
2616 			_formi_calculate_tabs(row);
2617 		  /*
2618 		   * if we are at the end of the string then back the
2619 		   * cursor pos up one to stick on the end of the line
2620 		   */
2621 		if (start == row->length) {
2622 			if (row->length > 1) {
2623 				if ((cur->rows + cur->nrows) == 1) {
2624 					pos = cur->row_xpos + cur->start_char;
2625 					cur->start_char =
2626 						tab_fit_window(
2627 							cur,
2628 							cur->start_char + cur->row_xpos,
2629 							cur->cols);
2630 					cur->row_xpos = pos - cur->start_char
2631 						- 1;
2632 					_formi_set_cursor_xpos(cur, FALSE);
2633 				} else {
2634 					if (cur->row_xpos == 0) {
2635 						if (row->next != NULL) {
2636 							if (_formi_join_line(
2637 								cur, &row,
2638 								JOIN_PREV_NW)
2639 							    != E_OK) {
2640 								return E_REQUEST_DENIED;
2641 							}
2642 						} else {
2643 							if (cur->row_count > 1)
2644 								cur->row_count--;
2645 						}
2646 
2647 					}
2648 
2649 					cur->row_xpos = start - 1;
2650 					cur->cursor_xpos =
2651 						_formi_tab_expanded_length(
2652 							row->string,
2653 							0, cur->row_xpos - 1);
2654 					if ((cur->cursor_xpos > 0)
2655 					    && (start != (row->expanded - 1)))
2656 						cur->cursor_xpos--;
2657 				}
2658 
2659 				start--;
2660 			} else {
2661 				start = 0;
2662 				cur->row_xpos = 0;
2663 				_formi_init_field_xpos(cur);
2664 			}
2665 		}
2666 
2667 		if ((cur->rows + cur->nrows) > 1) {
2668 			if (_formi_wrap_field(cur, row) != E_OK) {
2669 				bcopy(&row->string[start],
2670 				      &row->string[start + 1],
2671 				      (size_t) (end - start));
2672 				row->length++;
2673 				row->string[start] = saved;
2674 				_formi_wrap_field(cur, row);
2675 				return E_REQUEST_DENIED;
2676 			}
2677 		}
2678 		break;
2679 
2680 	case REQ_DEL_PREV:
2681 		if ((cur->cursor_xpos == 0) && (cur->start_char == 0)
2682 		    && (cur->start_line->prev == NULL)
2683 		    && (cur->cursor_ypos == 0))
2684 			   return E_REQUEST_DENIED;
2685 
2686 		row = cur->cur_line;
2687 		start = cur->row_xpos + cur->start_char;
2688 		end = row->length - 1;
2689 		eat_char = TRUE;
2690 
2691 		if ((cur->start_char + cur->row_xpos) == 0) {
2692 			if (row->prev == NULL)
2693 				return E_REQUEST_DENIED;
2694 
2695 			  /*
2696 			   * If we are a multiline field then check if
2697 			   * the line above has a hard return.  If it does
2698 			   * then just "eat" the hard return and re-wrap
2699 			   * the field.
2700 			   */
2701 			if (row->prev->hard_ret == TRUE) {
2702 				row->prev->hard_ret = FALSE;
2703 				if (_formi_join_line(cur, &row,
2704 						     JOIN_PREV) != E_OK) {
2705 					row->prev->hard_ret = TRUE;
2706 					return 0;
2707 				}
2708 
2709 				eat_char = FALSE;
2710 			} else {
2711 				start = row->prev->length;
2712 				  /*
2713 				   * Join this line to the previous
2714 				   * one.
2715 				   */
2716 				if (_formi_join_line(cur, &row,
2717 						     JOIN_PREV_NW) != E_OK) {
2718 					return 0;
2719 				}
2720 				end = row->length - 1;
2721 			}
2722 		}
2723 
2724 		if (eat_char == TRUE) {
2725 			  /*
2726 			   * eat a char from the buffer.  Normally we do
2727 			   * this unless we have deleted a "hard return"
2728 			   * in which case we just want to join the lines
2729 			   * without losing a char.
2730 			   */
2731 			saved = row->string[start - 1];
2732 			bcopy(&row->string[start], &row->string[start - 1],
2733 			      (size_t) (end - start + 1));
2734 			row->length--;
2735 			row->string[row->length] = '\0';
2736 			row->expanded = _formi_tab_expanded_length(
2737 				row->string, 0, row->length - 1);
2738 		}
2739 
2740 		if ((cur->rows + cur->nrows) == 1) {
2741 			_formi_calculate_tabs(row);
2742 			pos = cur->row_xpos + cur->start_char;
2743 			if (pos > 0)
2744 				pos--;
2745 			cur->start_char =
2746 				tab_fit_window(cur,
2747 					       cur->start_char + cur->row_xpos,
2748 					       cur->cols);
2749 			cur->row_xpos = pos - cur->start_char;
2750 			_formi_set_cursor_xpos(cur, FALSE);
2751 		} else {
2752 			if (eat_char == TRUE) {
2753 				cur->row_xpos--;
2754 				if (cur->row_xpos > 0)
2755 					cur->cursor_xpos =
2756 						_formi_tab_expanded_length(
2757 							row->string, 0,
2758 							cur->row_xpos - 1);
2759 				else
2760 					cur->cursor_xpos = 0;
2761 			}
2762 
2763 			if ((_formi_wrap_field(cur, row) != E_OK)) {
2764 				bcopy(&row->string[start - 1],
2765 				      &row->string[start],
2766 				      (size_t) (end - start));
2767 				row->length++;
2768 				row->string[start - 1] = saved;
2769 				row->string[row->length] = '\0';
2770 				_formi_wrap_field(cur, row);
2771 				return E_REQUEST_DENIED;
2772 			}
2773 		}
2774 		break;
2775 
2776 	case REQ_DEL_LINE:
2777 		if (((cur->rows + cur->nrows) == 1) ||
2778 		    (cur->row_count == 1)) {
2779 			  /* single line case */
2780 			row->length = 0;
2781 			row->expanded = row->length = 0;
2782 			cur->row_xpos = 0;
2783 			_formi_init_field_xpos(cur);
2784 			cur->cursor_ypos = 0;
2785 		} else {
2786 			  /* multiline field */
2787 			old_count = cur->row_count;
2788 			cur->row_count--;
2789 			if (cur->row_count == 0)
2790 				cur->row_count = 1;
2791 
2792 			if (old_count == 1) {
2793 				row->expanded = row->length = 0;
2794 				cur->cursor_xpos = 0;
2795 				cur->row_xpos = 0;
2796 				cur->cursor_ypos = 0;
2797 			} else
2798 				add_to_free(cur, row);
2799 
2800 			if (row->next == NULL) {
2801 				if (cur->cursor_ypos == 0) {
2802 					if (cur->start_line->prev != NULL) {
2803 						cur->start_line =
2804 							cur->start_line->prev;
2805 					}
2806 				} else {
2807 					cur->cursor_ypos--;
2808 				}
2809 			}
2810 
2811 			if (old_count > 1) {
2812 				if (cur->cursor_xpos > row->expanded) {
2813 					cur->cursor_xpos = row->expanded - 1;
2814 					cur->row_xpos = row->length - 1;
2815 				}
2816 
2817 				cur->start_line = cur->lines;
2818 				rs = cur->start_line;
2819 				cur->cursor_ypos = 0;
2820 				while (rs != row) {
2821 					if (cur->cursor_ypos < cur->rows)
2822 						cur->cursor_ypos++;
2823 					else
2824 						cur->start_line =
2825 							cur->start_line->next;
2826 					rs = rs->next;
2827 				}
2828 			}
2829 		}
2830 		break;
2831 
2832 	case REQ_DEL_WORD:
2833 		start = cur->start_char + cur->row_xpos;
2834 		str = row->string;
2835 
2836 		wb = find_eow(cur, start, TRUE, &row);
2837 		if (wb < 0)
2838 			return wb;
2839 
2840 		end = wb;
2841 
2842 		  /*
2843 		   * If not at the start of a word then find the start,
2844 		   * we cannot blindly call find_sow because this will
2845 		   * skip back a word if we are already at the start of
2846 		   * a word.
2847 		   */
2848 		if ((start > 0)
2849 		    && !(isblank(str[start - 1]) && !isblank(str[start])))
2850 			start = find_sow(start, &row);
2851 		str = row->string;
2852 		  /* XXXX hmmmm what if start and end on diff rows? XXXX */
2853 		bcopy(&str[end], &str[start],
2854 		      (size_t) (row->length - end + 1));
2855 		len = end - start;
2856 		row->length -= len;
2857 
2858 		if ((cur->rows + cur->nrows) > 1) {
2859 			row = cur->start_line + cur->cursor_ypos;
2860 			if (row->next != NULL) {
2861 				/*
2862 				 * if not on the last row we need to
2863 				 * join on the next row so the line
2864 				 * will be re-wrapped.
2865 				 */
2866 				_formi_join_line(cur, &row, JOIN_NEXT_NW);
2867 			}
2868 			_formi_wrap_field(cur, row);
2869 			cur->row_xpos = start;
2870 			cur->cursor_xpos = _formi_tab_expanded_length(
2871 				row->string, 0, cur->row_xpos);
2872 			if (cur->cursor_xpos > 0)
2873 				cur->cursor_xpos--;
2874 		} else {
2875 			_formi_calculate_tabs(row);
2876 			cur->row_xpos = start - cur->start_char;
2877 			if (cur->row_xpos > 0)
2878 				cur->row_xpos--;
2879 			_formi_set_cursor_xpos(cur, FALSE);
2880 		}
2881 		break;
2882 
2883 	case REQ_CLR_EOL:
2884 		row->string[cur->row_xpos + 1] = '\0';
2885 		row->length = cur->row_xpos + 1;
2886 		row->expanded = cur->cursor_xpos + 1;
2887 		break;
2888 
2889 	case REQ_CLR_EOF:
2890 		row = cur->cur_line->next;
2891 		while (row != NULL) {
2892 			rs = row->next;
2893 			add_to_free(cur, row);
2894 			row = rs;
2895 			cur->row_count--;
2896 		}
2897 		break;
2898 
2899 	case REQ_CLR_FIELD:
2900 		row = cur->lines->next;
2901 		cur->cur_line = cur->lines;
2902 		cur->start_line = cur->lines;
2903 
2904 		while (row != NULL) {
2905 			rs = row->next;
2906 			add_to_free(cur, row);
2907 			row = rs;
2908 		}
2909 
2910 		cur->lines->string[0] = '\0';
2911 		cur->lines->length = 0;
2912 		cur->lines->expanded = 0;
2913 		cur->row_count = 1;
2914 		cur->cursor_ypos = 0;
2915 		cur->row_xpos = 0;
2916 		_formi_init_field_xpos(cur);
2917 		cur->start_char = 0;
2918 		break;
2919 
2920 	case REQ_OVL_MODE:
2921 		cur->overlay = 1;
2922 		break;
2923 
2924 	case REQ_INS_MODE:
2925 		cur->overlay = 0;
2926 		break;
2927 
2928 	case REQ_SCR_FLINE:
2929 		_formi_scroll_fwd(cur, 1);
2930 		break;
2931 
2932 	case REQ_SCR_BLINE:
2933 		_formi_scroll_back(cur, 1);
2934 		break;
2935 
2936 	case REQ_SCR_FPAGE:
2937 		_formi_scroll_fwd(cur, cur->rows);
2938 		break;
2939 
2940 	case REQ_SCR_BPAGE:
2941 		_formi_scroll_back(cur, cur->rows);
2942 		break;
2943 
2944 	case REQ_SCR_FHPAGE:
2945 		_formi_scroll_fwd(cur, cur->rows / 2);
2946 		break;
2947 
2948 	case REQ_SCR_BHPAGE:
2949 		_formi_scroll_back(cur, cur->rows / 2);
2950 		break;
2951 
2952 	case REQ_SCR_FCHAR:
2953 		_formi_hscroll_fwd(cur, row, 1);
2954 		break;
2955 
2956 	case REQ_SCR_BCHAR:
2957 		_formi_hscroll_back(cur, row, 1);
2958 		break;
2959 
2960 	case REQ_SCR_HFLINE:
2961 		_formi_hscroll_fwd(cur, row, cur->cols);
2962 		break;
2963 
2964 	case REQ_SCR_HBLINE:
2965 		_formi_hscroll_back(cur, row, cur->cols);
2966 		break;
2967 
2968 	case REQ_SCR_HFHALF:
2969 		_formi_hscroll_fwd(cur, row, cur->cols / 2);
2970 		break;
2971 
2972 	case REQ_SCR_HBHALF:
2973 		_formi_hscroll_back(cur, row, cur->cols / 2);
2974 		break;
2975 
2976 	default:
2977 		return 0;
2978 	}
2979 
2980 #ifdef DEBUG
2981 	fprintf(dbg,
2982 	 "exit: cursor_xpos=%d, row_xpos=%d, start_char=%d, length=%d, allocated=%d\n",
2983 		cur->cursor_xpos, cur->row_xpos, cur->start_char,
2984 		cur->cur_line->length,	cur->cur_line->allocated);
2985 	fprintf(dbg, "exit: start_line=%p, ypos=%d\n", cur->start_line,
2986 		cur->cursor_ypos);
2987 	fprintf(dbg, "exit: string=\"%s\"\n", cur->cur_line->string);
2988 	assert ((cur->cursor_xpos < INT_MAX) && (cur->row_xpos < INT_MAX)
2989 		&& (cur->cursor_xpos >= cur->row_xpos));
2990 #endif
2991 	return 1;
2992 }
2993 
2994 /*
2995  * Validate the give character by passing it to any type character
2996  * checking routines, if they exist.
2997  */
2998 int
2999 _formi_validate_char(FIELD *field, char c)
3000 {
3001 	int ret_val;
3002 
3003 	if (field->type == NULL)
3004 		return E_OK;
3005 
3006 	ret_val = E_INVALID_FIELD;
3007 	_formi_do_char_validation(field, field->type, c, &ret_val);
3008 
3009 	return ret_val;
3010 }
3011 
3012 
3013 /*
3014  * Perform the validation of the character, invoke all field_type validation
3015  * routines.  If the field is ok then update ret_val to E_OK otherwise
3016  * ret_val is not changed.
3017  */
3018 static void
3019 _formi_do_char_validation(FIELD *field, FIELDTYPE *type, char c, int *ret_val)
3020 {
3021 	if ((type->flags & _TYPE_IS_LINKED) == _TYPE_IS_LINKED) {
3022 		_formi_do_char_validation(field, type->link->next, c, ret_val);
3023 		_formi_do_char_validation(field, type->link->prev, c, ret_val);
3024 	} else {
3025 		if (type->char_check == NULL)
3026 			*ret_val = E_OK;
3027 		else {
3028 			if (type->char_check((int)(unsigned char) c,
3029 					     field->args) == TRUE)
3030 				*ret_val = E_OK;
3031 		}
3032 	}
3033 }
3034 
3035 /*
3036  * Validate the current field.  If the field validation returns success then
3037  * return E_OK otherwise return E_INVALID_FIELD.
3038  *
3039  */
3040 int
3041 _formi_validate_field(FORM *form)
3042 {
3043 	FIELD *cur;
3044 	int ret_val, count;
3045 
3046 
3047 	if ((form == NULL) || (form->fields == NULL) ||
3048 	    (form->fields[0] == NULL))
3049 		return E_INVALID_FIELD;
3050 
3051 	cur = form->fields[form->cur_field];
3052 
3053 	  /*
3054 	   * Sync the buffer if it has been modified so the field
3055 	   * validation routines can use it and because this is
3056 	   * the correct behaviour according to AT&T implementation.
3057 	   */
3058 	if ((cur->buf0_status == TRUE)
3059 	    && ((ret_val = _formi_sync_buffer(cur)) != E_OK))
3060 			return ret_val;
3061 
3062 	  /*
3063 	   * If buffer is untouched then the string pointer may be
3064 	   * NULL, see if this is ok or not.
3065 	   */
3066 	if (cur->buffers[0].string == NULL) {
3067 		if ((cur->opts & O_NULLOK) == O_NULLOK)
3068 			return E_OK;
3069 		else
3070 			return E_INVALID_FIELD;
3071 	}
3072 
3073 	count = _formi_skip_blanks(cur->buffers[0].string, 0);
3074 
3075 	  /* check if we have a null field, depending on the nullok flag
3076 	   * this may be acceptable or not....
3077 	   */
3078 	if (cur->buffers[0].string[count] == '\0') {
3079 		if ((cur->opts & O_NULLOK) == O_NULLOK)
3080 			return E_OK;
3081 		else
3082 			return E_INVALID_FIELD;
3083 	}
3084 
3085 	  /* check if an unmodified field is ok */
3086 	if (cur->buf0_status == 0) {
3087 		if ((cur->opts & O_PASSOK) == O_PASSOK)
3088 			return E_OK;
3089 		else
3090 			return E_INVALID_FIELD;
3091 	}
3092 
3093 	  /* if there is no type then just accept the field */
3094 	if (cur->type == NULL)
3095 		return E_OK;
3096 
3097 	ret_val = E_INVALID_FIELD;
3098 	_formi_do_validation(cur, cur->type, &ret_val);
3099 
3100 	return ret_val;
3101 }
3102 
3103 /*
3104  * Perform the validation of the field, invoke all field_type validation
3105  * routines.  If the field is ok then update ret_val to E_OK otherwise
3106  * ret_val is not changed.
3107  */
3108 static void
3109 _formi_do_validation(FIELD *field, FIELDTYPE *type, int *ret_val)
3110 {
3111 	if ((type->flags & _TYPE_IS_LINKED) == _TYPE_IS_LINKED) {
3112 		_formi_do_validation(field, type->link->next, ret_val);
3113 		_formi_do_validation(field, type->link->prev, ret_val);
3114 	} else {
3115 		if (type->field_check == NULL)
3116 			*ret_val = E_OK;
3117 		else {
3118 			if (type->field_check(field, field_buffer(field, 0))
3119 			    == TRUE)
3120 				*ret_val = E_OK;
3121 		}
3122 	}
3123 }
3124 
3125 /*
3126  * Select the next/previous choice for the field, the driver command
3127  * selecting the direction will be passed in c.  Return 1 if a choice
3128  * selection succeeded, 0 otherwise.
3129  */
3130 int
3131 _formi_field_choice(FORM *form, int c)
3132 {
3133 	FIELDTYPE *type;
3134 	FIELD *field;
3135 
3136 	if ((form == NULL) || (form->fields == NULL) ||
3137 	    (form->fields[0] == NULL) ||
3138 	    (form->fields[form->cur_field]->type == NULL))
3139 		return 0;
3140 
3141 	field = form->fields[form->cur_field];
3142 	type = field->type;
3143 
3144 	switch (c) {
3145 	case REQ_NEXT_CHOICE:
3146 		if (type->next_choice == NULL)
3147 			return 0;
3148 		else
3149 			return type->next_choice(field,
3150 						 field_buffer(field, 0));
3151 
3152 	case REQ_PREV_CHOICE:
3153 		if (type->prev_choice == NULL)
3154 			return 0;
3155 		else
3156 			return type->prev_choice(field,
3157 						 field_buffer(field, 0));
3158 
3159 	default: /* should never happen! */
3160 		return 0;
3161 	}
3162 }
3163 
3164 /*
3165  * Update the fields if they have changed.  The parameter old has the
3166  * previous current field as the current field may have been updated by
3167  * the driver.  Return 1 if the form page needs updating.
3168  *
3169  */
3170 int
3171 _formi_update_field(FORM *form, int old_field)
3172 {
3173 	int cur, i;
3174 
3175 	cur = form->cur_field;
3176 
3177 	if (old_field != cur) {
3178 		if (!((cur >= form->page_starts[form->page].first) &&
3179 		      (cur <= form->page_starts[form->page].last))) {
3180 			  /* not on same page any more */
3181 			for (i = 0; i < form->max_page; i++) {
3182 				if ((form->page_starts[i].in_use == 1) &&
3183 				    (form->page_starts[i].first <= cur) &&
3184 				    (form->page_starts[i].last >= cur)) {
3185 					form->page = i;
3186 					return 1;
3187 				}
3188 			}
3189 		}
3190 	}
3191 
3192 	_formi_redraw_field(form, old_field);
3193 	_formi_redraw_field(form, form->cur_field);
3194 	return 0;
3195 }
3196 
3197 /*
3198  * Compare function for the field sorting
3199  *
3200  */
3201 static int
3202 field_sort_compare(const void *one, const void *two)
3203 {
3204 	const FIELD *a, *b;
3205 	int tl;
3206 
3207 	  /* LINTED const castaway; we don't modify these! */
3208 	a = (const FIELD *) *((const FIELD **) one);
3209 	b = (const FIELD *) *((const FIELD **) two);
3210 
3211 	if (a == NULL)
3212 		return 1;
3213 
3214 	if (b == NULL)
3215 		return -1;
3216 
3217 	  /*
3218 	   * First check the page, we want the fields sorted by page.
3219 	   *
3220 	   */
3221 	if (a->page != b->page)
3222 		return ((a->page > b->page)? 1 : -1);
3223 
3224 	tl = _formi_top_left(a->parent, a->index, b->index);
3225 
3226 	  /*
3227 	   * sort fields left to right, top to bottom so the top left is
3228 	   * the lesser value....
3229 	   */
3230 	return ((tl == a->index)? -1 : 1);
3231 }
3232 
3233 /*
3234  * Sort the fields in a form ready for driver traversal.
3235  */
3236 void
3237 _formi_sort_fields(FORM *form)
3238 {
3239 	FIELD **sort_area;
3240 	int i;
3241 
3242 	CIRCLEQ_INIT(&form->sorted_fields);
3243 
3244 	if ((sort_area = (FIELD **) malloc(sizeof(FIELD *) * form->field_count))
3245 	    == NULL)
3246 		return;
3247 
3248 	bcopy(form->fields, sort_area,
3249 	      (size_t) (sizeof(FIELD *) * form->field_count));
3250 	qsort(sort_area, (size_t) form->field_count, sizeof(FIELD *),
3251 	      field_sort_compare);
3252 
3253 	for (i = 0; i < form->field_count; i++)
3254 		CIRCLEQ_INSERT_TAIL(&form->sorted_fields, sort_area[i], glue);
3255 
3256 	free(sort_area);
3257 }
3258 
3259 /*
3260  * Set the neighbours for all the fields in the given form.
3261  */
3262 void
3263 _formi_stitch_fields(FORM *form)
3264 {
3265 	int above_row, below_row, end_above, end_below, cur_row, real_end;
3266 	FIELD *cur, *above, *below;
3267 
3268 	  /*
3269 	   * check if the sorted fields circle queue is empty, just
3270 	   * return if it is.
3271 	   */
3272 	if (CIRCLEQ_EMPTY(&form->sorted_fields))
3273 		return;
3274 
3275 	  /* initially nothing is above..... */
3276 	above_row = -1;
3277 	end_above = TRUE;
3278 	above = NULL;
3279 
3280 	  /* set up the first field as the current... */
3281 	cur = CIRCLEQ_FIRST(&form->sorted_fields);
3282 	cur_row = cur->form_row;
3283 
3284 	  /* find the first field on the next row if any */
3285 	below = CIRCLEQ_NEXT(cur, glue);
3286 	below_row = -1;
3287 	end_below = TRUE;
3288 	real_end = TRUE;
3289 	while (below != (void *)&form->sorted_fields) {
3290 		if (below->form_row != cur_row) {
3291 			below_row = below->form_row;
3292 			end_below = FALSE;
3293 			real_end = FALSE;
3294 			break;
3295 		}
3296 		below = CIRCLEQ_NEXT(below, glue);
3297 	}
3298 
3299 	  /* walk the sorted fields, setting the neighbour pointers */
3300 	while (cur != (void *) &form->sorted_fields) {
3301 		if (cur == CIRCLEQ_FIRST(&form->sorted_fields))
3302 			cur->left = NULL;
3303 		else
3304 			cur->left = CIRCLEQ_PREV(cur, glue);
3305 
3306 		if (cur == CIRCLEQ_LAST(&form->sorted_fields))
3307 			cur->right = NULL;
3308 		else
3309 			cur->right = CIRCLEQ_NEXT(cur, glue);
3310 
3311 		if (end_above == TRUE)
3312 			cur->up = NULL;
3313 		else {
3314 			cur->up = above;
3315 			above = CIRCLEQ_NEXT(above, glue);
3316 			if (above_row != above->form_row) {
3317 				end_above = TRUE;
3318 				above_row = above->form_row;
3319 			}
3320 		}
3321 
3322 		if (end_below == TRUE)
3323 			cur->down = NULL;
3324 		else {
3325 			cur->down = below;
3326 			below = CIRCLEQ_NEXT(below, glue);
3327 			if (below == (void *) &form->sorted_fields) {
3328 				end_below = TRUE;
3329 				real_end = TRUE;
3330 			} else if (below_row != below->form_row) {
3331 				end_below = TRUE;
3332 				below_row = below->form_row;
3333 			}
3334 		}
3335 
3336 		cur = CIRCLEQ_NEXT(cur, glue);
3337 		if ((cur != (void *) &form->sorted_fields)
3338 		    && (cur_row != cur->form_row)) {
3339 			cur_row = cur->form_row;
3340 			if (end_above == FALSE) {
3341 				for (; above != CIRCLEQ_FIRST(&form->sorted_fields);
3342 				     above = CIRCLEQ_NEXT(above, glue)) {
3343 					if (above->form_row != above_row) {
3344 						above_row = above->form_row;
3345 						break;
3346 					}
3347 				}
3348 			} else if (above == NULL) {
3349 				above = CIRCLEQ_FIRST(&form->sorted_fields);
3350 				end_above = FALSE;
3351 				above_row = above->form_row;
3352 			} else
3353 				end_above = FALSE;
3354 
3355 			if (end_below == FALSE) {
3356 				while (below_row == below->form_row) {
3357 					below = CIRCLEQ_NEXT(below,
3358 							     glue);
3359 					if (below ==
3360 					    (void *)&form->sorted_fields) {
3361 						real_end = TRUE;
3362 						end_below = TRUE;
3363 						break;
3364 					}
3365 				}
3366 
3367 				if (below != (void *)&form->sorted_fields)
3368 					below_row = below->form_row;
3369 			} else if (real_end == FALSE)
3370 				end_below = FALSE;
3371 
3372 		}
3373 	}
3374 }
3375 
3376 /*
3377  * Calculate the length of the displayed line allowing for any tab
3378  * characters that need to be expanded.  We assume that the tab stops
3379  * are 8 characters apart.  The parameters start and end are the
3380  * character positions in the string str we want to get the length of,
3381  * the function returns the number of characters from the start
3382  * position to the end position that should be displayed after any
3383  * intervening tabs have been expanded.
3384  */
3385 int
3386 _formi_tab_expanded_length(char *str, unsigned int start, unsigned int end)
3387 {
3388 	int len, start_len, i;
3389 
3390 	  /* if we have a null string then there is no length */
3391 	if (str[0] == '\0')
3392 		return 0;
3393 
3394 	len = 0;
3395 	start_len = 0;
3396 
3397 	  /*
3398 	   * preceding tabs affect the length tabs in the span, so
3399 	   * we need to calculate the length including the stuff before
3400 	   * start and then subtract off the unwanted bit.
3401 	   */
3402 	for (i = 0; i <= end; i++) {
3403 		if (i == start) /* stash preamble length for later */
3404 			start_len = len;
3405 
3406 		if (str[i] == '\0')
3407 			break;
3408 
3409 		if (str[i] == '\t')
3410 			len = len - (len % 8) + 8;
3411 		else
3412 			len++;
3413 	}
3414 
3415 #ifdef DEBUG
3416 	if (dbg != NULL) {
3417 		fprintf(dbg,
3418 		    "tab_expanded: start=%d, end=%d, expanded=%d (diff=%d)\n",
3419 			start, end, (len - start_len), (end - start));
3420 	}
3421 #endif
3422 
3423 	return (len - start_len);
3424 }
3425 
3426 /*
3427  * Calculate the tab stops on a given line in the field and set up
3428  * the tabs list with the results.  We do this by scanning the line for tab
3429  * characters and if one is found, noting the position and the number of
3430  * characters to get to the next tab stop.  This information is kept to
3431  * make manipulating the field (scrolling and so on) easier to handle.
3432  */
3433 void
3434 _formi_calculate_tabs(_FORMI_FIELD_LINES *row)
3435 {
3436 	_formi_tab_t *ts = row->tabs, *old_ts = NULL, **tsp;
3437 	int i, j;
3438 
3439 	  /*
3440 	   * If the line already has tabs then invalidate them by
3441 	   * walking the list and killing the in_use flag.
3442 	   */
3443 	for (; ts != NULL; ts = ts->fwd)
3444 		ts->in_use = FALSE;
3445 
3446 
3447 	  /*
3448 	   * Now look for tabs in the row and record the info...
3449 	   */
3450 	tsp = &row->tabs;
3451 	for (i = 0, j = 0; i < row->length; i++, j++) {
3452 		if (row->string[i] == '\t') {
3453 			if (*tsp == NULL) {
3454 				if ((*tsp = (_formi_tab_t *)
3455 				     malloc(sizeof(_formi_tab_t))) == NULL)
3456 					return;
3457 				(*tsp)->back = old_ts;
3458 				(*tsp)->fwd = NULL;
3459 			}
3460 
3461 			(*tsp)->in_use = TRUE;
3462 			(*tsp)->pos = i;
3463 			(*tsp)->size = 8 - (j % 8);
3464 			j += (*tsp)->size - 1;
3465 			old_ts = *tsp;
3466 			tsp = &(*tsp)->fwd;
3467 		}
3468 	}
3469 }
3470 
3471 /*
3472  * Return the size of the tab padding for a tab character at the given
3473  * position.  Return 1 if there is not a tab char entry matching the
3474  * given location.
3475  */
3476 static int
3477 tab_size(_FORMI_FIELD_LINES *row, unsigned int i)
3478 {
3479 	_formi_tab_t *ts;
3480 
3481 	ts = row->tabs;
3482 	while ((ts != NULL) && (ts->pos != i))
3483 		ts = ts->fwd;
3484 
3485 	if (ts == NULL)
3486 		return 1;
3487 	else
3488 		return ts->size;
3489 }
3490 
3491 /*
3492  * Find the character offset that corresponds to longest tab expanded
3493  * string that will fit into the given window.  Walk the string backwards
3494  * evaluating the sizes of any tabs that are in the string.  Note that
3495  * using this function on a multi-line window will produce undefined
3496  * results - it is really only required for a single row field.
3497  */
3498 static int
3499 tab_fit_window(FIELD *field, unsigned int pos, unsigned int window)
3500 {
3501 	int scroll_amt, i;
3502 	_formi_tab_t *ts;
3503 
3504 	  /* first find the last tab */
3505 	ts = field->lines->tabs;
3506 
3507 	  /*
3508 	   * unless there are no tabs - just return the window size,
3509 	   * if there is enough room, otherwise 0.
3510 	   */
3511 	if (ts == NULL) {
3512 		if (field->lines->length < window)
3513 			return 0;
3514 		else
3515 			return field->lines->length - window + 1;
3516 	}
3517 
3518 	while ((ts->fwd != NULL) && (ts->fwd->in_use == TRUE))
3519 		ts = ts->fwd;
3520 
3521 	  /*
3522 	   * now walk backwards finding the first tab that is to the
3523 	   * left of our starting pos.
3524 	   */
3525 	while ((ts != NULL) && (ts->in_use == TRUE) && (ts->pos > pos))
3526 		ts = ts->back;
3527 
3528 	scroll_amt = 0;
3529 	for (i = pos; i >= 0; i--) {
3530 		if (field->lines->string[i] == '\t') {
3531 			assert((ts != NULL) && (ts->in_use == TRUE));
3532 			if (ts->pos == i) {
3533 				if ((scroll_amt + ts->size) > window) {
3534 					break;
3535 				}
3536 				scroll_amt += ts->size;
3537 				ts = ts->back;
3538 			}
3539 			else
3540 				assert(ts->pos == i);
3541 		} else {
3542 			scroll_amt++;
3543 			if (scroll_amt > window)
3544 				break;
3545 		}
3546 	}
3547 
3548 	return ++i;
3549 }
3550 
3551 /*
3552  * Return the position of the last character that will fit into the
3553  * given width after tabs have been expanded for a given row of a given
3554  * field.
3555  */
3556 static unsigned int
3557 tab_fit_len(_FORMI_FIELD_LINES *row, unsigned int width)
3558 {
3559 	unsigned int pos, len, row_pos;
3560 	_formi_tab_t *ts;
3561 
3562 	ts = row->tabs;
3563 	pos = 0;
3564 	len = 0;
3565 	row_pos = 0;
3566 
3567 	if (width == 0)
3568 		return 0;
3569 
3570 	while ((len < width) && (pos < row->length)) {
3571 		if (row->string[pos] == '\t') {
3572 			assert((ts != NULL) && (ts->in_use == TRUE));
3573 			if (ts->pos == row_pos) {
3574 				if ((len + ts->size) > width)
3575 					break;
3576 				len += ts->size;
3577 				ts = ts->fwd;
3578 			}
3579 			else
3580 				assert(ts->pos == row_pos);
3581 		} else
3582 			len++;
3583 		pos++;
3584 		row_pos++;
3585 	}
3586 
3587 	if (pos > 0)
3588 		pos--;
3589 	return pos;
3590 }
3591 
3592 /*
3593  * Sync the field line structures with the contents of buffer 0 for that
3594  * field.  We do this by walking all the line structures and concatenating
3595  * all the strings into one single string in buffer 0.
3596  */
3597 int
3598 _formi_sync_buffer(FIELD *field)
3599 {
3600 	_FORMI_FIELD_LINES *line;
3601 	char *nstr, *tmp;
3602 	unsigned length;
3603 
3604 	if (field->lines == NULL)
3605 		return E_BAD_ARGUMENT;
3606 
3607 	if (field->lines->string == NULL)
3608 		return E_BAD_ARGUMENT;
3609 
3610 	  /*
3611 	   * init nstr up front, just in case there are no line contents,
3612 	   * this could happen if the field just contains hard returns.
3613 	   */
3614 	if ((nstr = malloc(sizeof(char))) == NULL)
3615 		return E_SYSTEM_ERROR;
3616 	nstr[0] = '\0';
3617 
3618 	line = field->lines;
3619 	length = 1; /* allow for terminating null */
3620 
3621 	while (line != NULL) {
3622 		if (line->length != 0) {
3623 			if ((tmp = realloc(nstr,
3624 					   (size_t) (length + line->length)))
3625 			    == NULL) {
3626 				if (nstr != NULL)
3627 					free(nstr);
3628 				return (E_SYSTEM_ERROR);
3629 			}
3630 
3631 			nstr = tmp;
3632 			strcat(nstr, line->string);
3633 			length += line->length;
3634 		}
3635 
3636 		line = line->next;
3637 	}
3638 
3639 	if (field->buffers[0].string != NULL)
3640 		free(field->buffers[0].string);
3641 	field->buffers[0].allocated = length;
3642 	field->buffers[0].length = length - 1;
3643 	field->buffers[0].string = nstr;
3644 	return E_OK;
3645 }
3646 
3647 
3648 
3649