xref: /netbsd-src/lib/libform/internals.c (revision ba65fde2d7fefa7d39838fa5fa855e62bd606b5e)
1 /*	$NetBSD: internals.c,v 1.36 2013/01/19 16:11:03 mbalmer 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 1.36 2013/01/19 16:11:03 mbalmer 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->alines;
143 	while (rs != line) {
144 		rs = rs->next;
145 		ypos++;
146 	}
147 
148 	field->cursor_ypos = ypos;
149 	field->start_line = field->alines;
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->alines = line->next;
182 		field->alines->prev = NULL;
183 
184 		if (field->cur_line == saved)
185 			field->cur_line = field->alines;
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->alines->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->alines->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((unsigned char)row->string[pos])) &&
623 			    ((field->opts & O_WRAP) == O_WRAP)) {
624 				if (!isblank((unsigned char)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((unsigned char)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((unsigned char)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((unsigned char)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->alines = 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((unsigned char)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((unsigned char)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((unsigned char)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((unsigned char)row->string[start]));
1219 
1220 	do {
1221 		  /* otherwise skip the whitespace.... */
1222 		while ((row->string[start] != '\0')
1223 		       && isblank((unsigned char)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((unsigned char)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((unsigned char)str[start]) ||
1270 			    isblank((unsigned char)str[start - 1])) {
1271 				if (isblank((unsigned char)str[start - 1]))
1272 					start--;
1273 				  /* skip the whitespace.... */
1274 				while ((start >= 0) &&
1275 				    isblank((unsigned char)str[start]))
1276 					start--;
1277 			}
1278 		}
1279 
1280 		  /* see if we hit the start of the string */
1281 		if (start < 0) {
1282 			do {
1283 				if (row->prev == NULL) {
1284 					*rowp = row;
1285 					start = 0;
1286 					return start;
1287 				} else {
1288 					row = row->prev;
1289 					str = row->string;
1290 					if (row->length > 0)
1291 						start = row->length - 1;
1292 					else
1293 						start = 0;
1294 				}
1295 			} while (row->length == 0);
1296 		}
1297 	} while (isblank((unsigned char)row->string[start]));
1298 
1299 	  /* see if we hit the start of the string */
1300 	if (start < 0) {
1301 		*rowp = row;
1302 		return 0;
1303 	}
1304 
1305 	  /* now skip any non-whitespace */
1306 	do {
1307 		while ((start >= 0) && !isblank((unsigned char)str[start]))
1308 			start--;
1309 
1310 
1311 		if (start < 0) {
1312 			do {
1313 				if (row->prev == NULL) {
1314 					*rowp = row;
1315 					start = 0;
1316 					return start;
1317 				} else {
1318 					row = row->prev;
1319 					str = row->string;
1320 					if (row->length > 0)
1321 						start = row->length - 1;
1322 					else
1323 						start = 0;
1324 				}
1325 			} while (row->length == 0);
1326 		}
1327 	} while (!isblank((unsigned char)str[start]));
1328 
1329 	if (start > 0) {
1330 		start++; /* last loop has us pointing at a space, adjust */
1331 		if (start >= row->length) {
1332 			if (row->next != NULL) {
1333 				start = 0;
1334 				row = row->next;
1335 			} else {
1336 				start = row->length - 1;
1337 			}
1338 		}
1339 	}
1340 
1341 	if (start < 0)
1342 		start = 0;
1343 
1344 	*rowp = row;
1345 	return start;
1346 }
1347 
1348 /*
1349  * Scroll the field forward the given number of lines.
1350  */
1351 static void
1352 _formi_scroll_fwd(FIELD *field, unsigned int amt)
1353 {
1354 	unsigned int count;
1355 	_FORMI_FIELD_LINES *end_row;
1356 
1357 	end_row = field->start_line;
1358 	  /* walk the line structs forward to find the bottom of the field */
1359 	count = field->rows - 1;
1360 	while ((count > 0) && (end_row->next != NULL))
1361 	{
1362 		count--;
1363 		end_row = end_row->next;
1364 	}
1365 
1366 	  /* check if there are lines to scroll */
1367 	if ((count > 0) && (end_row->next == NULL))
1368 		return;
1369 
1370 	  /*
1371 	   * ok, lines to scroll - do this by walking both the start_line
1372 	   * and the end_row at the same time for amt lines, we stop when
1373 	   * either we have done the number of lines or end_row hits the
1374 	   * last line in the field.
1375 	   */
1376 	count = amt;
1377 	while ((count > 0) && (end_row->next != NULL)) {
1378 		count--;
1379 		field->start_line = field->start_line->next;
1380 		end_row = end_row->next;
1381 	}
1382 }
1383 
1384 /*
1385  * Scroll the field backward the given number of lines.
1386  */
1387 static void
1388 _formi_scroll_back(FIELD *field, unsigned int amt)
1389 {
1390 	unsigned int count;
1391 
1392 	  /* check for lines above */
1393 	if (field->start_line->prev == NULL)
1394 		return;
1395 
1396 	  /*
1397 	   * Backward scroll is easy, follow row struct chain backward until
1398 	   * the number of lines done or we reach the top of the field.
1399 	   */
1400 	count = amt;
1401 	while ((count > 0) && (field->start_line->prev != NULL)) {
1402 		count--;
1403 		field->start_line = field->start_line->prev;
1404 	}
1405 }
1406 
1407 /*
1408  * Scroll the field forward the given number of characters.
1409  */
1410 void
1411 _formi_hscroll_fwd(FIELD *field, _FORMI_FIELD_LINES *row, int unsigned amt)
1412 {
1413 	unsigned int end, scroll_amt, expanded;
1414 	_formi_tab_t *ts;
1415 
1416 
1417 	if ((row->tabs == NULL) || (row->tabs->in_use == FALSE)) {
1418 		  /* if the line has no tabs things are easy... */
1419 		end =  field->start_char + field->cols + amt - 1;
1420 		scroll_amt = amt;
1421 		if (end > row->length) {
1422 			end = row->length;
1423 			scroll_amt = end - field->start_char - field->cols + 1;
1424 		}
1425 	} else {
1426 		  /*
1427 		   * If there are tabs we need to add on the scroll amount,
1428 		   * find the last char position that will fit into
1429 		   * the field and finally fix up the start_char.  This
1430 		   * is a lot of work but handling the case where there
1431 		   * are not enough chars to scroll by amt is difficult.
1432 		   */
1433 		end = field->start_char + field->row_xpos + amt;
1434 		if (end >= row->length)
1435 			end = row->length - 1;
1436 		else {
1437 			expanded = _formi_tab_expanded_length(
1438 				row->string,
1439 				field->start_char + amt,
1440 				field->start_char + field->row_xpos + amt);
1441 			ts = row->tabs;
1442 			  /* skip tabs to the lhs of our starting point */
1443 			while ((ts != NULL) && (ts->in_use == TRUE)
1444 			       && (ts->pos < end))
1445 				ts = ts->fwd;
1446 
1447 			while ((expanded <= field->cols)
1448 			       && (end < row->length)) {
1449 				if (row->string[end] == '\t') {
1450 					assert((ts != NULL)
1451 					       && (ts->in_use == TRUE));
1452 					if (ts->pos == end) {
1453 						if ((expanded + ts->size)
1454 						    > field->cols)
1455 							break;
1456 						expanded += ts->size;
1457 						ts = ts->fwd;
1458 					}
1459 					else
1460 						assert(ts->pos == end);
1461 				} else
1462 					expanded++;
1463 				end++;
1464 			}
1465 		}
1466 
1467 		scroll_amt = tab_fit_window(field, end, field->cols);
1468 		if (scroll_amt < field->start_char)
1469 			scroll_amt = 1;
1470 		else
1471 			scroll_amt -= field->start_char;
1472 
1473 		scroll_amt = min(scroll_amt, amt);
1474 	}
1475 
1476 	field->start_char += scroll_amt;
1477 	field->cursor_xpos =
1478 		_formi_tab_expanded_length(row->string,
1479 					   field->start_char,
1480 					   field->row_xpos
1481 					   + field->start_char) - 1;
1482 
1483 }
1484 
1485 /*
1486  * Scroll the field backward the given number of characters.
1487  */
1488 void
1489 _formi_hscroll_back(FIELD *field, _FORMI_FIELD_LINES *row, unsigned int amt)
1490 {
1491 	field->start_char -= min(field->start_char, amt);
1492 	field->cursor_xpos =
1493 		_formi_tab_expanded_length(row->string, field->start_char,
1494 					   field->row_xpos
1495 					   + field->start_char) - 1;
1496 	if (field->cursor_xpos >= field->cols) {
1497 		field->row_xpos = 0;
1498 		field->cursor_xpos = 0;
1499 	}
1500 }
1501 
1502 /*
1503  * Find the different pages in the form fields and assign the form
1504  * page_starts array with the information to find them.
1505  */
1506 int
1507 _formi_find_pages(FORM *form)
1508 {
1509 	int i, cur_page = 0;
1510 
1511 	if ((form->page_starts = (_FORMI_PAGE_START *)
1512 	     malloc((form->max_page + 1) * sizeof(_FORMI_PAGE_START))) == NULL)
1513 		return E_SYSTEM_ERROR;
1514 
1515 	  /* initialise the page starts array */
1516 	memset(form->page_starts, 0,
1517 	       (form->max_page + 1) * sizeof(_FORMI_PAGE_START));
1518 
1519 	for (i =0; i < form->field_count; i++) {
1520 		if (form->fields[i]->page_break == 1)
1521 			cur_page++;
1522 		if (form->page_starts[cur_page].in_use == 0) {
1523 			form->page_starts[cur_page].in_use = 1;
1524 			form->page_starts[cur_page].first = i;
1525 			form->page_starts[cur_page].last = i;
1526 			form->page_starts[cur_page].top_left = i;
1527 			form->page_starts[cur_page].bottom_right = i;
1528 		} else {
1529 			form->page_starts[cur_page].last = i;
1530 			form->page_starts[cur_page].top_left =
1531 				_formi_top_left(form,
1532 						form->page_starts[cur_page].top_left,
1533 						i);
1534 			form->page_starts[cur_page].bottom_right =
1535 				_formi_bottom_right(form,
1536 						    form->page_starts[cur_page].bottom_right,
1537 						    i);
1538 		}
1539 	}
1540 
1541 	return E_OK;
1542 }
1543 
1544 /*
1545  * Completely redraw the field of the given form.
1546  */
1547 void
1548 _formi_redraw_field(FORM *form, int field)
1549 {
1550 	unsigned int pre, post, flen, slen, i, j, start, line;
1551 	unsigned int tab, cpos, len;
1552 	char *str, c;
1553 	FIELD *cur;
1554 	_FORMI_FIELD_LINES *row;
1555 #ifdef DEBUG
1556 	char buffer[100];
1557 #endif
1558 
1559 	cur = form->fields[field];
1560 	flen = cur->cols;
1561 	slen = 0;
1562 	start = 0;
1563 	line = 0;
1564 
1565 	for (row = cur->start_line; ((row != NULL) && (line < cur->rows));
1566 	     row = row->next, line++) {
1567 		wmove(form->scrwin, (int) (cur->form_row + line),
1568 		      (int) cur->form_col);
1569 		if ((cur->rows + cur->nrows) == 1) {
1570 			if ((cur->cols + cur->start_char) >= row->length)
1571 				len = row->length;
1572 			else
1573 				len = cur->cols + cur->start_char;
1574 			if (row->string != NULL)
1575 				slen = _formi_tab_expanded_length(
1576 					row->string, cur->start_char, len);
1577 			else
1578 				slen = 0;
1579 
1580 			if (slen > cur->cols)
1581 				slen = cur->cols;
1582 			slen += cur->start_char;
1583 		} else
1584 			slen = row->expanded;
1585 
1586 		if ((cur->opts & O_STATIC) == O_STATIC) {
1587 			switch (cur->justification) {
1588 			case JUSTIFY_RIGHT:
1589 				post = 0;
1590 				if (flen < slen)
1591 					pre = 0;
1592 				else
1593 					pre = flen - slen;
1594 				break;
1595 
1596 			case JUSTIFY_CENTER:
1597 				if (flen < slen) {
1598 					pre = 0;
1599 					post = 0;
1600 				} else {
1601 					pre = flen - slen;
1602 					post = pre = pre / 2;
1603 					  /* get padding right if
1604 					     centring is not even */
1605 					if ((post + pre + slen) < flen)
1606 						post++;
1607 				}
1608 				break;
1609 
1610 			case NO_JUSTIFICATION:
1611 			case JUSTIFY_LEFT:
1612 			default:
1613 				pre = 0;
1614 				if (flen <= slen)
1615 					post = 0;
1616 				else {
1617 					post = flen - slen;
1618 					if (post > flen)
1619 						post = flen;
1620 				}
1621 				break;
1622 			}
1623 		} else {
1624 			  /* dynamic fields are not justified */
1625 			pre = 0;
1626 			if (flen <= slen)
1627 				post = 0;
1628 			else {
1629 				post = flen - slen;
1630 				if (post > flen)
1631 					post = flen;
1632 			}
1633 
1634 			  /* but they do scroll.... */
1635 
1636 			if (pre > cur->start_char - start)
1637 				pre = pre - cur->start_char + start;
1638 			else
1639 				pre = 0;
1640 
1641 			if (slen > cur->start_char) {
1642 				slen -= cur->start_char;
1643 				if (slen > flen)
1644 					post = 0;
1645 				else
1646 					post = flen - slen;
1647 
1648 				if (post > flen)
1649 					post = flen;
1650 			} else {
1651 				slen = 0;
1652 				post = flen - pre;
1653 			}
1654 		}
1655 
1656 		if (form->cur_field == field)
1657 			wattrset(form->scrwin, cur->fore);
1658 		else
1659 			wattrset(form->scrwin, cur->back);
1660 
1661 		str = &row->string[cur->start_char];
1662 
1663 #ifdef DEBUG
1664 		if (_formi_create_dbg_file() == E_OK) {
1665 			fprintf(dbg,
1666   "redraw_field: start=%d, pre=%d, slen=%d, flen=%d, post=%d, start_char=%d\n",
1667 				start, pre, slen, flen, post, cur->start_char);
1668 			if (str != NULL) {
1669 				if (row->expanded != 0) {
1670 					strncpy(buffer, str, flen);
1671 				} else {
1672 					strcpy(buffer, "(empty)");
1673 				}
1674 			} else {
1675 				strcpy(buffer, "(null)");
1676 			}
1677 			buffer[flen] = '\0';
1678 			fprintf(dbg, "redraw_field: %s\n", buffer);
1679 		}
1680 #endif
1681 
1682 		for (i = start + cur->start_char; i < pre; i++)
1683 			waddch(form->scrwin, cur->pad);
1684 
1685 #ifdef DEBUG
1686 		fprintf(dbg, "redraw_field: will add %d chars\n",
1687 			min(slen, flen));
1688 #endif
1689 		for (i = 0, cpos = cur->start_char; i < min(slen, flen);
1690 		     i++, str++, cpos++)
1691 		{
1692 			c = *str;
1693 			tab = 0; /* just to shut gcc up */
1694 #ifdef DEBUG
1695 			fprintf(dbg, "adding char str[%d]=%c\n",
1696 				cpos + cur->start_char,	c);
1697 #endif
1698 			if (((cur->opts & O_PUBLIC) != O_PUBLIC)) {
1699 				if (c == '\t')
1700 					tab = add_tab(form, row, cpos,
1701 						      cur->pad);
1702 				else
1703 					waddch(form->scrwin, cur->pad);
1704 			} else if ((cur->opts & O_VISIBLE) == O_VISIBLE) {
1705 				if (c == '\t')
1706 					tab = add_tab(form, row, cpos, ' ');
1707 				else
1708 					waddch(form->scrwin, c);
1709 			} else {
1710 				if (c == '\t')
1711 					tab = add_tab(form, row, cpos, ' ');
1712 				else
1713 					waddch(form->scrwin, ' ');
1714 			}
1715 
1716 			  /*
1717 			   * If we have had a tab then skip forward
1718 			   * the requisite number of chars to keep
1719 			   * things in sync.
1720 			   */
1721 			if (c == '\t')
1722 				i += tab - 1;
1723 		}
1724 
1725 		for (i = 0; i < post; i++)
1726 			waddch(form->scrwin, cur->pad);
1727 	}
1728 
1729 	for (i = line; i < cur->rows; i++) {
1730 		wmove(form->scrwin, (int) (cur->form_row + i),
1731 		      (int) cur->form_col);
1732 
1733 		if (form->cur_field == field)
1734 			wattrset(form->scrwin, cur->fore);
1735 		else
1736 			wattrset(form->scrwin, cur->back);
1737 
1738 		for (j = 0; j < cur->cols; j++) {
1739 			waddch(form->scrwin, cur->pad);
1740 		}
1741 	}
1742 
1743 	wattrset(form->scrwin, cur->back);
1744 	return;
1745 }
1746 
1747 /*
1748  * Add the correct number of the given character to simulate a tab
1749  * in the field.
1750  */
1751 static int
1752 add_tab(FORM *form, _FORMI_FIELD_LINES *row, unsigned int i, char c)
1753 {
1754 	int j;
1755 	_formi_tab_t *ts = row->tabs;
1756 
1757 	while ((ts != NULL) && (ts->pos != i))
1758 		ts = ts->fwd;
1759 
1760 	assert(ts != NULL);
1761 
1762 	for (j = 0; j < ts->size; j++)
1763 		waddch(form->scrwin, c);
1764 
1765 	return ts->size;
1766 }
1767 
1768 
1769 /*
1770  * Display the fields attached to the form that are on the current page
1771  * on the screen.
1772  *
1773  */
1774 int
1775 _formi_draw_page(FORM *form)
1776 {
1777 	int i;
1778 
1779 	if (form->page_starts[form->page].in_use == 0)
1780 		return E_BAD_ARGUMENT;
1781 
1782 	wclear(form->scrwin);
1783 
1784 	for (i = form->page_starts[form->page].first;
1785 	     i <= form->page_starts[form->page].last; i++)
1786 		_formi_redraw_field(form, i);
1787 
1788 	return E_OK;
1789 }
1790 
1791 /*
1792  * Add the character c at the position pos in buffer 0 of the given field
1793  */
1794 int
1795 _formi_add_char(FIELD *field, unsigned int pos, char c)
1796 {
1797 	char *new, old_c;
1798 	unsigned int new_size;
1799 	int status;
1800 	_FORMI_FIELD_LINES *row, *temp, *next_temp;
1801 
1802 	row = field->cur_line;
1803 
1804 	  /*
1805 	   * If buffer has not had a string before, set it to a blank
1806 	   * string.  Everything should flow from there....
1807 	   */
1808 	if (row->string == NULL) {
1809 		if ((row->string = (char *) malloc((size_t)INITIAL_LINE_ALLOC))
1810 		    == NULL)
1811 			return E_SYSTEM_ERROR;
1812 		row->string[0] = '\0';
1813 		row->allocated = INITIAL_LINE_ALLOC;
1814 		row->length = 0;
1815 		row->expanded = 0;
1816 	}
1817 
1818 	if (_formi_validate_char(field, c) != E_OK) {
1819 #ifdef DEBUG
1820 		fprintf(dbg, "add_char: char %c failed char validation\n", c);
1821 #endif
1822 		return E_INVALID_FIELD;
1823 	}
1824 
1825 	if ((c == '\t') && (field->cols <= 8)) {
1826 #ifdef DEBUG
1827 		fprintf(dbg, "add_char: field too small for a tab\n");
1828 #endif
1829 		return E_NO_ROOM;
1830 	}
1831 
1832 #ifdef DEBUG
1833 	fprintf(dbg, "add_char: pos=%d, char=%c\n", pos, c);
1834 	fprintf(dbg, "add_char enter: xpos=%d, row_pos=%d, start=%d\n",
1835 		field->cursor_xpos, field->row_xpos, field->start_char);
1836 	fprintf(dbg, "add_char enter: length=%d(%d), allocated=%d\n",
1837 		row->expanded, row->length, row->allocated);
1838 	fprintf(dbg, "add_char enter: %s\n", row->string);
1839 	fprintf(dbg, "add_char enter: buf0_status=%d\n", field->buf0_status);
1840 #endif
1841 	if (((field->opts & O_BLANK) == O_BLANK) &&
1842 	    (field->buf0_status == FALSE) &&
1843 	    ((field->row_xpos + field->start_char) == 0)) {
1844 		row = field->alines;
1845 		if (row->next != NULL) {
1846 			  /* shift all but one line structs to free list */
1847 			temp = row->next;
1848 			do {
1849 				next_temp = temp->next;
1850 				add_to_free(field, temp);
1851 				temp = next_temp;
1852 			} while (temp != NULL);
1853 		}
1854 
1855 		row->length = 0;
1856 		row->string[0] = '\0';
1857 		pos = 0;
1858 		field->start_char = 0;
1859 		field->start_line = row;
1860 		field->cur_line = row;
1861 		field->row_count = 1;
1862 		field->row_xpos = 0;
1863 		field->cursor_ypos = 0;
1864 		row->expanded = 0;
1865 		row->length = 0;
1866 		_formi_init_field_xpos(field);
1867 	}
1868 
1869 
1870 	if ((field->overlay == 0)
1871 	    || ((field->overlay == 1) && (pos >= row->length))) {
1872 		  /* first check if the field can have more chars...*/
1873 		if (check_field_size(field) == FALSE)
1874 			return E_REQUEST_DENIED;
1875 
1876 		if (row->length + 2
1877 		    >= row->allocated) {
1878 			new_size = row->allocated + 16 - (row->allocated % 16);
1879 			if ((new = (char *) realloc(row->string,
1880 						  (size_t) new_size )) == NULL)
1881 				return E_SYSTEM_ERROR;
1882 			row->allocated = new_size;
1883 			row->string = new;
1884 		}
1885 	}
1886 
1887 	if ((field->overlay == 0) && (row->length > pos)) {
1888 		bcopy(&row->string[pos], &row->string[pos + 1],
1889 		      (size_t) (row->length - pos + 1));
1890 	}
1891 
1892 	old_c = row->string[pos];
1893 	row->string[pos] = c;
1894 	if (pos >= row->length) {
1895 		  /* make sure the string is terminated if we are at the
1896 		   * end of the string, the terminator would be missing
1897 		   * if we are are at the end of the field.
1898 		   */
1899 		row->string[pos + 1] = '\0';
1900 	}
1901 
1902 	  /* only increment the length if we are inserting characters
1903 	   * OR if we are at the end of the field in overlay mode.
1904 	   */
1905 	if ((field->overlay == 0)
1906 	    || ((field->overlay == 1) && (pos >= row->length))) {
1907 		row->length++;
1908 	}
1909 
1910 	_formi_calculate_tabs(row);
1911 	row->expanded = _formi_tab_expanded_length(row->string, 0,
1912 						   row->length - 1);
1913 
1914 	  /* wrap the field, if needed */
1915 	status = _formi_wrap_field(field, row);
1916 
1917 	row = field->cur_line;
1918 	pos = field->row_xpos;
1919 
1920 	  /*
1921 	   * check the wrap worked or that we have not exceeded the
1922 	   * max field size - this can happen if the field is re-wrapped
1923 	   * and the row count is increased past the set limit.
1924 	   */
1925 	if ((status != E_OK) || (check_field_size(field) == FALSE)) {
1926 		if ((field->overlay == 0)
1927 		    || ((field->overlay == 1)
1928 			&& (pos >= (row->length - 1) /*XXXX- append check???*/))) {
1929 			  /*
1930 			   * wrap failed for some reason, back out the
1931 			   * char insert
1932 			   */
1933 			bcopy(&row->string[pos + 1], &row->string[pos],
1934 			      (size_t) (row->length - pos));
1935 			row->length--;
1936 			if (pos > 0)
1937 				pos--;
1938 		} else if (field->overlay == 1) {
1939 			  /* back out character overlay */
1940 			row->string[pos] = old_c;
1941 		}
1942 
1943 		_formi_calculate_tabs(row);
1944 
1945 		_formi_wrap_field(field, row);
1946 		  /*
1947 		   * If we are here then either the status is bad or we
1948 		   * simply ran out of room.  If the status is E_OK then
1949 		   * we ran out of room, let the form driver know this.
1950 		   */
1951 		if (status == E_OK)
1952 			status = E_REQUEST_DENIED;
1953 
1954 	} else {
1955 		field->buf0_status = TRUE;
1956 		field->row_xpos++;
1957 		if ((field->rows + field->nrows) == 1) {
1958 			status = _formi_set_cursor_xpos(field, FALSE);
1959 		} else {
1960 			field->cursor_xpos =
1961 				_formi_tab_expanded_length(
1962 					row->string, 0,	field->row_xpos - 1);
1963 
1964 			  /*
1965 			   * Annoying corner case - if we are right in
1966 			   * the bottom right corner of the field we
1967 			   * need to scroll the field one line so the
1968 			   * cursor is positioned correctly in the
1969 			   * field.
1970 			   */
1971 			if ((field->cursor_xpos >= field->cols) &&
1972 			    (field->cursor_ypos == (field->rows - 1))) {
1973 				field->cursor_ypos--;
1974 				field->start_line = field->start_line->next;
1975 			}
1976 		}
1977 	}
1978 
1979 	assert((field->cursor_xpos <= field->cols)
1980 	       && (field->cursor_ypos < 400000));
1981 
1982 #ifdef DEBUG
1983 	fprintf(dbg, "add_char exit: xpos=%d, row_pos=%d, start=%d\n",
1984 		field->cursor_xpos, field->row_xpos, field->start_char);
1985 	fprintf(dbg, "add_char_exit: length=%d(%d), allocated=%d\n",
1986 		row->expanded, row->length, row->allocated);
1987 	fprintf(dbg, "add_char exit: ypos=%d, start_line=%p\n",
1988 		field->cursor_ypos, field->start_line);
1989 	fprintf(dbg,"add_char exit: %s\n", row->string);
1990 	fprintf(dbg, "add_char exit: buf0_status=%d\n", field->buf0_status);
1991 	fprintf(dbg, "add_char exit: status = %s\n",
1992 		(status == E_OK)? "OK" : "FAILED");
1993 #endif
1994 	return status;
1995 }
1996 
1997 /*
1998  * Set the position of the cursor on the screen in the row depending on
1999  * where the current position in the string is and the justification
2000  * that is to be applied to the field.  Justification is only applied
2001  * to single row, static fields.
2002  */
2003 static int
2004 _formi_set_cursor_xpos(FIELD *field, int noscroll)
2005 {
2006 	int just, pos;
2007 
2008 	just = field->justification;
2009 	pos = field->start_char + field->row_xpos;
2010 
2011 #ifdef DEBUG
2012 	fprintf(dbg,
2013 	  "cursor_xpos enter: pos %d, start_char %d, row_xpos %d, xpos %d\n",
2014 		pos, field->start_char, field->row_xpos, field->cursor_xpos);
2015 #endif
2016 
2017 	  /*
2018 	   * make sure we apply the correct justification to non-static
2019 	   * fields.
2020 	   */
2021 	if (((field->rows + field->nrows) != 1) ||
2022 	    ((field->opts & O_STATIC) != O_STATIC))
2023 		just = JUSTIFY_LEFT;
2024 
2025 	switch (just) {
2026 	case JUSTIFY_RIGHT:
2027 		field->cursor_xpos = field->cols - 1
2028 			- _formi_tab_expanded_length(
2029 				field->cur_line->string, 0,
2030 				field->cur_line->length - 1)
2031 			+ _formi_tab_expanded_length(
2032 				field->cur_line->string, 0,
2033 				field->row_xpos);
2034 		break;
2035 
2036 	case JUSTIFY_CENTER:
2037 		field->cursor_xpos = ((field->cols - 1)
2038 			- _formi_tab_expanded_length(
2039 				field->cur_line->string, 0,
2040 				field->cur_line->length - 1) + 1) / 2
2041 			+ _formi_tab_expanded_length(field->cur_line->string,
2042 						     0, field->row_xpos);
2043 
2044 		if (field->cursor_xpos > (field->cols - 1))
2045 			field->cursor_xpos = (field->cols - 1);
2046 		break;
2047 
2048 	default:
2049 		field->cursor_xpos = _formi_tab_expanded_length(
2050 			field->cur_line->string,
2051 			field->start_char,
2052 			field->row_xpos	+ field->start_char);
2053 		if ((field->cursor_xpos <= (field->cols - 1)) &&
2054 		    ((field->start_char + field->row_xpos)
2055 		     < field->cur_line->length))
2056 			field->cursor_xpos--;
2057 
2058 		if (field->cursor_xpos > (field->cols - 1)) {
2059 			if ((field->opts & O_STATIC) == O_STATIC) {
2060 				field->start_char = 0;
2061 
2062 				if (field->row_xpos
2063 				    == (field->cur_line->length - 1)) {
2064 					field->cursor_xpos = field->cols - 1;
2065 				} else {
2066 					field->cursor_xpos =
2067 						_formi_tab_expanded_length(
2068 						  field->cur_line->string,
2069 						  field->start_char,
2070 						  field->row_xpos
2071 						    + field->start_char
2072 						  - 1) - 1;
2073 				}
2074 			} else {
2075 				if (noscroll == FALSE) {
2076 					field->start_char =
2077 						tab_fit_window(
2078 							field,
2079 							field->start_char
2080 							+ field->row_xpos,
2081 							field->cols);
2082 					field->row_xpos = pos
2083 						- field->start_char;
2084 					field->cursor_xpos =
2085 						_formi_tab_expanded_length(
2086 						   field->cur_line->string,
2087 						   field->start_char,
2088 						   field->row_xpos
2089 						      + field->start_char - 1);
2090 				} else {
2091 					field->cursor_xpos = (field->cols - 1);
2092 				}
2093 			}
2094 
2095 		}
2096 		break;
2097 	}
2098 
2099 #ifdef DEBUG
2100 	fprintf(dbg,
2101 	  "cursor_xpos exit: pos %d, start_char %d, row_xpos %d, xpos %d\n",
2102 		pos, field->start_char, field->row_xpos, field->cursor_xpos);
2103 #endif
2104 	return E_OK;
2105 }
2106 
2107 /*
2108  * Manipulate the text in a field, this takes the given form and performs
2109  * the passed driver command on the current text field.  Returns 1 if the
2110  * text field was modified.
2111  */
2112 int
2113 _formi_manipulate_field(FORM *form, int c)
2114 {
2115 	FIELD *cur;
2116 	char *str, saved;
2117 	unsigned int start, end, pos, status, old_count, size;
2118 	unsigned int old_xpos, old_row_pos;
2119 	int len, wb;
2120 	bool eat_char;
2121 	_FORMI_FIELD_LINES *row, *rs;
2122 
2123 	cur = form->fields[form->cur_field];
2124 	if (cur->cur_line->string == NULL)
2125 		return E_REQUEST_DENIED;
2126 
2127 #ifdef DEBUG
2128 	fprintf(dbg, "entry: request is REQ_%s\n", reqs[c - REQ_MIN_REQUEST]);
2129 	fprintf(dbg,
2130 	"entry: xpos=%d, row_pos=%d, start_char=%d, length=%d, allocated=%d\n",
2131 		cur->cursor_xpos, cur->row_xpos, cur->start_char,
2132 		cur->cur_line->length,	cur->cur_line->allocated);
2133 	fprintf(dbg, "entry: start_line=%p, ypos=%d\n", cur->start_line,
2134 		cur->cursor_ypos);
2135 	fprintf(dbg, "entry: string=");
2136 	if (cur->cur_line->string == NULL)
2137 		fprintf(dbg, "(null)\n");
2138 	else
2139 		fprintf(dbg, "\"%s\"\n", cur->cur_line->string);
2140 #endif
2141 
2142 	  /* Cannot manipulate a null string! */
2143 	if (cur->cur_line->string == NULL)
2144 		return E_REQUEST_DENIED;
2145 
2146 	saved = '\0';
2147 	row = cur->cur_line;
2148 
2149 	switch (c) {
2150 	case REQ_RIGHT_CHAR:
2151 		  /*
2152 		   * The right_char request performs the same function
2153 		   * as the next_char request except that the cursor is
2154 		   * not wrapped if it is at the end of the line, so
2155 		   * check if the cursor is at the end of the line and
2156 		   * deny the request otherwise just fall through to
2157 		   * the next_char request handler.
2158 		   */
2159 		if (cur->cursor_xpos >= cur->cols - 1)
2160 			return E_REQUEST_DENIED;
2161 
2162 		  /* FALLTHRU */
2163 
2164 	case REQ_NEXT_CHAR:
2165 		  /* for a dynamic field allow an offset of one more
2166 		   * char so we can insert chars after end of string.
2167 		   * Static fields cannot do this so deny request if
2168 		   * cursor is at the end of the field.
2169 		   */
2170 		if (((cur->opts & O_STATIC) == O_STATIC) &&
2171 		    (cur->row_xpos == cur->cols - 1) &&
2172 		    ((cur->rows + cur->nrows) == 1))
2173 			return E_REQUEST_DENIED;
2174 
2175 		if (((cur->rows + cur->nrows) == 1) &&
2176 		    (cur->row_xpos + cur->start_char + 1) > row->length)
2177 			return E_REQUEST_DENIED;
2178 
2179 		if ((cur->rows + cur->nrows) == 1) {
2180 			cur->row_xpos++;
2181 			_formi_set_cursor_xpos(cur, (c == REQ_RIGHT_CHAR));
2182 		} else {
2183 			if (cur->cursor_xpos >= (row->expanded - 1)) {
2184 				if ((row->next == NULL) ||
2185 				    (c == REQ_RIGHT_CHAR))
2186 					return E_REQUEST_DENIED;
2187 
2188 				cur->cursor_xpos = 0;
2189 				cur->row_xpos = 0;
2190 				cur->cur_line = cur->cur_line->next;
2191 				if (cur->cursor_ypos == (cur->rows - 1))
2192 					cur->start_line =
2193 						cur->start_line->next;
2194 				else
2195 					cur->cursor_ypos++;
2196 			} else {
2197 				old_xpos = cur->cursor_xpos;
2198 				old_row_pos = cur->row_xpos;
2199 				if (row->string[cur->row_xpos] == '\t')
2200 					cur->cursor_xpos += tab_size(row,
2201 							cur->row_xpos);
2202 				else
2203 					cur->cursor_xpos++;
2204 				cur->row_xpos++;
2205 				if (cur->cursor_xpos
2206 				    >= row->expanded) {
2207 					if ((row->next == NULL) ||
2208 					    (c == REQ_RIGHT_CHAR)) {
2209 						cur->cursor_xpos = old_xpos;
2210 						cur->row_xpos = old_row_pos;
2211 						return E_REQUEST_DENIED;
2212 					}
2213 
2214 					cur->cursor_xpos = 0;
2215 					cur->row_xpos = 0;
2216 					cur->cur_line = cur->cur_line->next;
2217 					if (cur->cursor_ypos
2218 					    == (cur->rows - 1))
2219 						cur->start_line =
2220 							cur->start_line->next;
2221 					else
2222 						cur->cursor_ypos++;
2223 				}
2224 			}
2225 		}
2226 
2227 		break;
2228 
2229 	case REQ_LEFT_CHAR:
2230 		  /*
2231 		   * The behaviour of left_char is the same as prev_char
2232 		   * except that the cursor will not wrap if it has
2233 		   * reached the LHS of the field, so just check this
2234 		   * and fall through if we are not at the LHS.
2235 		   */
2236 		if (cur->cursor_xpos == 0)
2237 			return E_REQUEST_DENIED;
2238 
2239 		  /* FALLTHRU */
2240 	case REQ_PREV_CHAR:
2241 		if ((cur->rows + cur->nrows) == 1) {
2242 			if (cur->row_xpos == 0) {
2243 				if (cur->start_char > 0)
2244 					cur->start_char--;
2245 				else
2246 					return E_REQUEST_DENIED;
2247 			} else {
2248 				cur->row_xpos--;
2249 				_formi_set_cursor_xpos(cur, FALSE);
2250 			}
2251 		} else {
2252 			if ((cur->cursor_xpos == 0) &&
2253 			    (cur->cursor_ypos == 0) &&
2254 			    (cur->start_line->prev == NULL))
2255 				return E_REQUEST_DENIED;
2256 
2257 			pos = cur->row_xpos;
2258 			if (cur->cursor_xpos > 0) {
2259 				if (row->string[pos] == '\t') {
2260 					size = tab_size(row, pos);
2261 					if (size > cur->cursor_xpos) {
2262 						cur->cursor_xpos = 0;
2263 						cur->row_xpos = 0;
2264 					} else {
2265 						cur->row_xpos--;
2266 						cur->cursor_xpos -= size;
2267 					}
2268 				} else {
2269 					cur->cursor_xpos--;
2270 					cur->row_xpos--;
2271 				}
2272 			} else {
2273 				cur->cur_line = cur->cur_line->prev;
2274 				if (cur->cursor_ypos > 0)
2275 					cur->cursor_ypos--;
2276 				else
2277 					cur->start_line =
2278 						cur->start_line->prev;
2279 				row = cur->cur_line;
2280 				if (row->expanded > 0) {
2281 					cur->cursor_xpos = row->expanded - 1;
2282 				} else {
2283 					cur->cursor_xpos = 0;
2284 				}
2285 
2286 				if (row->length > 0)
2287 					cur->row_xpos = row->length - 1;
2288 				else
2289 					cur->row_xpos = 0;
2290 			}
2291 		}
2292 
2293 		break;
2294 
2295 	case REQ_DOWN_CHAR:
2296 		  /*
2297 		   * The down_char request has the same functionality as
2298 		   * the next_line request excepting that the field is not
2299 		   * scrolled if the cursor is at the bottom of the field.
2300 		   * Check to see if the cursor is at the bottom of the field
2301 		   * and if it is then deny the request otherwise fall
2302 		   * through to the next_line handler.
2303 		   */
2304 		if (cur->cursor_ypos >= cur->rows - 1)
2305 			return E_REQUEST_DENIED;
2306 
2307 		  /* FALLTHRU */
2308 
2309 	case REQ_NEXT_LINE:
2310 		if ((row->next == NULL) || (cur->cur_line->next == NULL))
2311 			return E_REQUEST_DENIED;
2312 
2313 		cur->cur_line = cur->cur_line->next;
2314 		if ((cur->cursor_ypos + 1) >= cur->rows) {
2315 			cur->start_line = cur->start_line->next;
2316 		} else
2317 			cur->cursor_ypos++;
2318 		row = cur->cur_line;
2319 
2320 		if (row->length == 0) {
2321 			cur->row_xpos = 0;
2322 			cur->cursor_xpos = 0;
2323 		} else {
2324 			if (cur->cursor_xpos > (row->expanded - 1))
2325 				cur->cursor_xpos = row->expanded - 1;
2326 
2327 			cur->row_xpos =	tab_fit_len(row, cur->cursor_xpos + 1);
2328 			if (cur->row_xpos == 0)
2329 				cur->cursor_xpos = 0;
2330 			else
2331 				cur->cursor_xpos =
2332 					_formi_tab_expanded_length(
2333 						row->string, 0, cur->row_xpos);
2334 			if (cur->cursor_xpos > 0)
2335 				cur->cursor_xpos--;
2336 		}
2337 		break;
2338 
2339 	case REQ_UP_CHAR:
2340 		  /*
2341 		   * The up_char request has the same functionality as
2342 		   * the prev_line request excepting the field is not
2343 		   * scrolled, check if the cursor is at the top of the
2344 		   * field, if it is deny the request otherwise fall
2345 		   * through to the prev_line handler.
2346 		   */
2347 		if (cur->cursor_ypos == 0)
2348 			return E_REQUEST_DENIED;
2349 
2350 		  /* FALLTHRU */
2351 
2352 	case REQ_PREV_LINE:
2353 		if (cur->cur_line->prev == NULL)
2354 			return E_REQUEST_DENIED;
2355 
2356 		if (cur->cursor_ypos == 0) {
2357 			if (cur->start_line->prev == NULL)
2358 				return E_REQUEST_DENIED;
2359 			cur->start_line = cur->start_line->prev;
2360 		} else
2361 			cur->cursor_ypos--;
2362 
2363 		cur->cur_line = cur->cur_line->prev;
2364 		row = cur->cur_line;
2365 
2366 		if (row->length == 0) {
2367 			cur->row_xpos = 0;
2368 			cur->cursor_xpos = 0;
2369 		} else {
2370 			if (cur->cursor_xpos > (row->expanded - 1))
2371 				cur->cursor_xpos = row->expanded - 1;
2372 
2373 			cur->row_xpos =	tab_fit_len(row, cur->cursor_xpos + 1);
2374 			cur->cursor_xpos =
2375 				_formi_tab_expanded_length(row->string,
2376 							   0, cur->row_xpos);
2377 			if (cur->cursor_xpos > 0)
2378 				cur->cursor_xpos--;
2379 		}
2380 		break;
2381 
2382 	case REQ_NEXT_WORD:
2383 		start = cur->row_xpos + cur->start_char;
2384 		str = row->string;
2385 
2386 		wb = find_eow(cur, start, FALSE, &row);
2387 		if (wb < 0)
2388 			return wb;
2389 
2390 		start = wb;
2391 		  /* check if we hit the end */
2392 		if (str[start] == '\0')
2393 			return E_REQUEST_DENIED;
2394 
2395 		  /* otherwise we must have found the start of a word...*/
2396 		if ((cur->rows + cur->nrows) == 1) {
2397 			  /* single line field */
2398 			size = _formi_tab_expanded_length(str,
2399 				cur->start_char, start);
2400 			if (size < cur->cols) {
2401 				cur->row_xpos = start - cur->start_char;
2402 			} else {
2403 				cur->start_char = start;
2404 				cur->row_xpos = 0;
2405 			}
2406 			_formi_set_cursor_xpos(cur, FALSE);
2407 		} else {
2408 			  /* multiline field */
2409 			cur->cur_line = row;
2410 			adjust_ypos(cur, row);
2411 
2412 			cur->row_xpos = start;
2413 			cur->cursor_xpos =
2414 				_formi_tab_expanded_length(
2415 					row->string, 0, cur->row_xpos) - 1;
2416 		}
2417 		break;
2418 
2419 	case REQ_PREV_WORD:
2420 		start = cur->start_char + cur->row_xpos;
2421 		if (cur->start_char > 0)
2422 			start--;
2423 
2424 		if ((start == 0) && (row->prev == NULL))
2425 			return E_REQUEST_DENIED;
2426 
2427 		if (start == 0) {
2428 			row = row->prev;
2429 			if (row->length > 0)
2430 				start = row->length - 1;
2431 			else
2432 				start = 0;
2433 		}
2434 
2435 		str = row->string;
2436 
2437 		start = find_sow(start, &row);
2438 
2439 		if ((cur->rows + cur->nrows) == 1) {
2440 			  /* single line field */
2441 			size = _formi_tab_expanded_length(str,
2442 				cur->start_char, start);
2443 
2444 			if (start > cur->start_char) {
2445 				cur->row_xpos = start - cur->start_char;
2446 			} else {
2447 				cur->start_char = start;
2448 				cur->row_xpos = 0;
2449 			}
2450 			_formi_set_cursor_xpos(cur, FALSE);
2451 		} else {
2452 			  /* multiline field */
2453 			cur->cur_line = row;
2454 			adjust_ypos(cur, row);
2455 			cur->row_xpos = start;
2456 			cur->cursor_xpos =
2457 				_formi_tab_expanded_length(
2458 					row->string, 0,
2459 					cur->row_xpos) - 1;
2460 		}
2461 
2462 		break;
2463 
2464 	case REQ_BEG_FIELD:
2465 		cur->start_char = 0;
2466 		while (cur->start_line->prev != NULL)
2467 			cur->start_line = cur->start_line->prev;
2468 		cur->cur_line = cur->start_line;
2469 		cur->row_xpos = 0;
2470 		_formi_init_field_xpos(cur);
2471 		cur->cursor_ypos = 0;
2472 		break;
2473 
2474 	case REQ_BEG_LINE:
2475 		cur->row_xpos = 0;
2476 		_formi_init_field_xpos(cur);
2477 		cur->start_char = 0;
2478 		break;
2479 
2480 	case REQ_END_FIELD:
2481 		while (cur->cur_line->next != NULL)
2482 			cur->cur_line = cur->cur_line->next;
2483 
2484 		if (cur->row_count > cur->rows) {
2485 			cur->start_line = cur->cur_line;
2486 			pos = cur->rows - 1;
2487 			while (pos > 0) {
2488 				cur->start_line = cur->start_line->prev;
2489 				pos--;
2490 			}
2491 			cur->cursor_ypos = cur->rows - 1;
2492 		} else {
2493 			cur->cursor_ypos = cur->row_count - 1;
2494 		}
2495 
2496 		  /* we fall through here deliberately, we are on the
2497 		   * correct row, now we need to get to the end of the
2498 		   * line.
2499 		   */
2500 		  /* FALLTHRU */
2501 
2502 	case REQ_END_LINE:
2503 		row = cur->cur_line;
2504 
2505 		if ((cur->rows + cur->nrows) == 1) {
2506 			if (row->expanded > cur->cols - 1) {
2507 				if ((cur->opts & O_STATIC) != O_STATIC) {
2508 					cur->start_char = tab_fit_window(
2509 						cur, row->length,
2510 						cur->cols) + 1;
2511 					cur->row_xpos = row->length
2512 						- cur->start_char;
2513 				} else {
2514 					cur->start_char = 0;
2515 					cur->row_xpos = cur->cols - 1;
2516 				}
2517 			} else {
2518 				cur->row_xpos = row->length + 1;
2519 				cur->start_char = 0;
2520 			}
2521 			_formi_set_cursor_xpos(cur, FALSE);
2522 		} else {
2523 			cur->row_xpos = row->length - 1;
2524 			cur->cursor_xpos = row->expanded - 1;
2525 			if (row->next == NULL) {
2526 				cur->row_xpos++;
2527 				cur->cursor_xpos++;
2528 			}
2529 		}
2530 		break;
2531 
2532 	case REQ_NEW_LINE:
2533 		start = cur->start_char	+ cur->row_xpos;
2534 		if ((status = split_line(cur, TRUE, start, &row)) != E_OK)
2535 			return status;
2536 		cur->cur_line->hard_ret = TRUE;
2537 		cur->cursor_xpos = 0;
2538 		cur->row_xpos = 0;
2539 		break;
2540 
2541 	case REQ_INS_CHAR:
2542 		if ((status = _formi_add_char(cur, cur->start_char
2543 					      + cur->row_xpos,
2544 					      cur->pad)) != E_OK)
2545 			return status;
2546 		break;
2547 
2548 	case REQ_INS_LINE:
2549 		if ((status = split_line(cur, TRUE, 0, &row)) != E_OK)
2550 			return status;
2551 		cur->cur_line->hard_ret = TRUE;
2552 		break;
2553 
2554 	case REQ_DEL_CHAR:
2555 		row = cur->cur_line;
2556 		start = cur->start_char + cur->row_xpos;
2557 		end = row->length - 1;
2558 		if ((start >= row->length) && (row->next == NULL))
2559 			return E_REQUEST_DENIED;
2560 
2561 		if ((start == row->length - 1) || (row->length == 0)) {
2562 			if ((cur->rows + cur->nrows) > 1) {
2563 				/*
2564 				 * Firstly, check if the current line has
2565 				 * a hard return.  In this case we just
2566 				 * want to "delete" the hard return and
2567 				 * re-wrap the field.  The hard return
2568 				 * does not occupy a character space in
2569 				 * the buffer but we must make it appear
2570 				 * like it does for a deletion.
2571 				 */
2572 				if (row->hard_ret == TRUE) {
2573 					row->hard_ret = FALSE;
2574 					if (_formi_join_line(cur, &row,
2575 							     JOIN_NEXT)
2576 					    != E_OK) {
2577 						row->hard_ret = TRUE;
2578 						return 0;
2579 					} else {
2580 						return 1;
2581 					}
2582 				}
2583 
2584 				/*
2585 				 * If we have more than one row, join the
2586 				 * next row to make things easier unless
2587 				 * we are at the end of the string, in
2588 				 * that case the join would fail but we
2589 				 * really want to delete the last char
2590 				 * in the field.
2591 				 */
2592 				if (row->next != NULL) {
2593 					if (_formi_join_line(cur, &row,
2594 							     JOIN_NEXT_NW)
2595 					    != E_OK) {
2596 						return E_REQUEST_DENIED;
2597 					}
2598 				}
2599 			}
2600 		}
2601 
2602 		saved = row->string[start];
2603 		bcopy(&row->string[start + 1], &row->string[start],
2604 		      (size_t) (end - start + 1));
2605 		row->string[end] = '\0';
2606 		row->length--;
2607 		if (row->length > 0)
2608 			row->expanded = _formi_tab_expanded_length(
2609 				row->string, 0, row->length - 1);
2610 		else
2611 			row->expanded = 0;
2612 
2613 		  /*
2614 		   * recalculate tabs for a single line field, multiline
2615 		   * fields will do this when the field is wrapped.
2616 		   */
2617 		if ((cur->rows + cur->nrows) == 1)
2618 			_formi_calculate_tabs(row);
2619 		  /*
2620 		   * if we are at the end of the string then back the
2621 		   * cursor pos up one to stick on the end of the line
2622 		   */
2623 		if (start == row->length) {
2624 			if (row->length > 1) {
2625 				if ((cur->rows + cur->nrows) == 1) {
2626 					pos = cur->row_xpos + cur->start_char;
2627 					cur->start_char =
2628 						tab_fit_window(
2629 							cur,
2630 							cur->start_char + cur->row_xpos,
2631 							cur->cols);
2632 					cur->row_xpos = pos - cur->start_char
2633 						- 1;
2634 					_formi_set_cursor_xpos(cur, FALSE);
2635 				} else {
2636 					if (cur->row_xpos == 0) {
2637 						if (row->next != NULL) {
2638 							if (_formi_join_line(
2639 								cur, &row,
2640 								JOIN_PREV_NW)
2641 							    != E_OK) {
2642 								return E_REQUEST_DENIED;
2643 							}
2644 						} else {
2645 							if (cur->row_count > 1)
2646 								cur->row_count--;
2647 						}
2648 
2649 					}
2650 
2651 					cur->row_xpos = start - 1;
2652 					cur->cursor_xpos =
2653 						_formi_tab_expanded_length(
2654 							row->string,
2655 							0, cur->row_xpos - 1);
2656 					if ((cur->cursor_xpos > 0)
2657 					    && (start != (row->expanded - 1)))
2658 						cur->cursor_xpos--;
2659 				}
2660 
2661 				start--;
2662 			} else {
2663 				start = 0;
2664 				cur->row_xpos = 0;
2665 				_formi_init_field_xpos(cur);
2666 			}
2667 		}
2668 
2669 		if ((cur->rows + cur->nrows) > 1) {
2670 			if (_formi_wrap_field(cur, row) != E_OK) {
2671 				bcopy(&row->string[start],
2672 				      &row->string[start + 1],
2673 				      (size_t) (end - start));
2674 				row->length++;
2675 				row->string[start] = saved;
2676 				_formi_wrap_field(cur, row);
2677 				return E_REQUEST_DENIED;
2678 			}
2679 		}
2680 		break;
2681 
2682 	case REQ_DEL_PREV:
2683 		if ((cur->cursor_xpos == 0) && (cur->start_char == 0)
2684 		    && (cur->start_line->prev == NULL)
2685 		    && (cur->cursor_ypos == 0))
2686 			   return E_REQUEST_DENIED;
2687 
2688 		row = cur->cur_line;
2689 		start = cur->row_xpos + cur->start_char;
2690 		end = row->length - 1;
2691 		eat_char = TRUE;
2692 
2693 		if ((cur->start_char + cur->row_xpos) == 0) {
2694 			if (row->prev == NULL)
2695 				return E_REQUEST_DENIED;
2696 
2697 			  /*
2698 			   * If we are a multiline field then check if
2699 			   * the line above has a hard return.  If it does
2700 			   * then just "eat" the hard return and re-wrap
2701 			   * the field.
2702 			   */
2703 			if (row->prev->hard_ret == TRUE) {
2704 				row->prev->hard_ret = FALSE;
2705 				if (_formi_join_line(cur, &row,
2706 						     JOIN_PREV) != E_OK) {
2707 					row->prev->hard_ret = TRUE;
2708 					return 0;
2709 				}
2710 
2711 				eat_char = FALSE;
2712 			} else {
2713 				start = row->prev->length;
2714 				  /*
2715 				   * Join this line to the previous
2716 				   * one.
2717 				   */
2718 				if (_formi_join_line(cur, &row,
2719 						     JOIN_PREV_NW) != E_OK) {
2720 					return 0;
2721 				}
2722 				end = row->length - 1;
2723 			}
2724 		}
2725 
2726 		if (eat_char == TRUE) {
2727 			  /*
2728 			   * eat a char from the buffer.  Normally we do
2729 			   * this unless we have deleted a "hard return"
2730 			   * in which case we just want to join the lines
2731 			   * without losing a char.
2732 			   */
2733 			saved = row->string[start - 1];
2734 			bcopy(&row->string[start], &row->string[start - 1],
2735 			      (size_t) (end - start + 1));
2736 			row->length--;
2737 			row->string[row->length] = '\0';
2738 			row->expanded = _formi_tab_expanded_length(
2739 				row->string, 0, row->length - 1);
2740 		}
2741 
2742 		if ((cur->rows + cur->nrows) == 1) {
2743 			_formi_calculate_tabs(row);
2744 			pos = cur->row_xpos + cur->start_char;
2745 			if (pos > 0)
2746 				pos--;
2747 			cur->start_char =
2748 				tab_fit_window(cur,
2749 					       cur->start_char + cur->row_xpos,
2750 					       cur->cols);
2751 			cur->row_xpos = pos - cur->start_char;
2752 			_formi_set_cursor_xpos(cur, FALSE);
2753 		} else {
2754 			if (eat_char == TRUE) {
2755 				cur->row_xpos--;
2756 				if (cur->row_xpos > 0)
2757 					cur->cursor_xpos =
2758 						_formi_tab_expanded_length(
2759 							row->string, 0,
2760 							cur->row_xpos - 1);
2761 				else
2762 					cur->cursor_xpos = 0;
2763 			}
2764 
2765 			if ((_formi_wrap_field(cur, row) != E_OK)) {
2766 				bcopy(&row->string[start - 1],
2767 				      &row->string[start],
2768 				      (size_t) (end - start));
2769 				row->length++;
2770 				row->string[start - 1] = saved;
2771 				row->string[row->length] = '\0';
2772 				_formi_wrap_field(cur, row);
2773 				return E_REQUEST_DENIED;
2774 			}
2775 		}
2776 		break;
2777 
2778 	case REQ_DEL_LINE:
2779 		if (((cur->rows + cur->nrows) == 1) ||
2780 		    (cur->row_count == 1)) {
2781 			  /* single line case */
2782 			row->length = 0;
2783 			row->expanded = row->length = 0;
2784 			cur->row_xpos = 0;
2785 			_formi_init_field_xpos(cur);
2786 			cur->cursor_ypos = 0;
2787 		} else {
2788 			  /* multiline field */
2789 			old_count = cur->row_count;
2790 			cur->row_count--;
2791 			if (cur->row_count == 0)
2792 				cur->row_count = 1;
2793 
2794 			if (old_count == 1) {
2795 				row->expanded = row->length = 0;
2796 				cur->cursor_xpos = 0;
2797 				cur->row_xpos = 0;
2798 				cur->cursor_ypos = 0;
2799 			} else
2800 				add_to_free(cur, row);
2801 
2802 			if (row->next == NULL) {
2803 				if (cur->cursor_ypos == 0) {
2804 					if (cur->start_line->prev != NULL) {
2805 						cur->start_line =
2806 							cur->start_line->prev;
2807 					}
2808 				} else {
2809 					cur->cursor_ypos--;
2810 				}
2811 			}
2812 
2813 			if (old_count > 1) {
2814 				if (cur->cursor_xpos > row->expanded) {
2815 					cur->cursor_xpos = row->expanded - 1;
2816 					cur->row_xpos = row->length - 1;
2817 				}
2818 
2819 				cur->start_line = cur->alines;
2820 				rs = cur->start_line;
2821 				cur->cursor_ypos = 0;
2822 				while (rs != row) {
2823 					if (cur->cursor_ypos < cur->rows)
2824 						cur->cursor_ypos++;
2825 					else
2826 						cur->start_line =
2827 							cur->start_line->next;
2828 					rs = rs->next;
2829 				}
2830 			}
2831 		}
2832 		break;
2833 
2834 	case REQ_DEL_WORD:
2835 		start = cur->start_char + cur->row_xpos;
2836 		str = row->string;
2837 
2838 		wb = find_eow(cur, start, TRUE, &row);
2839 		if (wb < 0)
2840 			return wb;
2841 
2842 		end = wb;
2843 
2844 		  /*
2845 		   * If not at the start of a word then find the start,
2846 		   * we cannot blindly call find_sow because this will
2847 		   * skip back a word if we are already at the start of
2848 		   * a word.
2849 		   */
2850 		if ((start > 0)
2851 		    && !(isblank((unsigned char)str[start - 1]) &&
2852 			!isblank((unsigned char)str[start])))
2853 			start = find_sow(start, &row);
2854 		str = row->string;
2855 		  /* XXXX hmmmm what if start and end on diff rows? XXXX */
2856 		bcopy(&str[end], &str[start],
2857 		      (size_t) (row->length - end + 1));
2858 		len = end - start;
2859 		row->length -= len;
2860 
2861 		if ((cur->rows + cur->nrows) > 1) {
2862 			row = cur->start_line + cur->cursor_ypos;
2863 			if (row->next != NULL) {
2864 				/*
2865 				 * if not on the last row we need to
2866 				 * join on the next row so the line
2867 				 * will be re-wrapped.
2868 				 */
2869 				_formi_join_line(cur, &row, JOIN_NEXT_NW);
2870 			}
2871 			_formi_wrap_field(cur, row);
2872 			cur->row_xpos = start;
2873 			cur->cursor_xpos = _formi_tab_expanded_length(
2874 				row->string, 0, cur->row_xpos);
2875 			if (cur->cursor_xpos > 0)
2876 				cur->cursor_xpos--;
2877 		} else {
2878 			_formi_calculate_tabs(row);
2879 			cur->row_xpos = start - cur->start_char;
2880 			if (cur->row_xpos > 0)
2881 				cur->row_xpos--;
2882 			_formi_set_cursor_xpos(cur, FALSE);
2883 		}
2884 		break;
2885 
2886 	case REQ_CLR_EOL:
2887 		row->string[cur->row_xpos + 1] = '\0';
2888 		row->length = cur->row_xpos + 1;
2889 		row->expanded = cur->cursor_xpos + 1;
2890 		break;
2891 
2892 	case REQ_CLR_EOF:
2893 		row = cur->cur_line->next;
2894 		while (row != NULL) {
2895 			rs = row->next;
2896 			add_to_free(cur, row);
2897 			row = rs;
2898 			cur->row_count--;
2899 		}
2900 		break;
2901 
2902 	case REQ_CLR_FIELD:
2903 		row = cur->alines->next;
2904 		cur->cur_line = cur->alines;
2905 		cur->start_line = cur->alines;
2906 
2907 		while (row != NULL) {
2908 			rs = row->next;
2909 			add_to_free(cur, row);
2910 			row = rs;
2911 		}
2912 
2913 		cur->alines->string[0] = '\0';
2914 		cur->alines->length = 0;
2915 		cur->alines->expanded = 0;
2916 		cur->row_count = 1;
2917 		cur->cursor_ypos = 0;
2918 		cur->row_xpos = 0;
2919 		_formi_init_field_xpos(cur);
2920 		cur->start_char = 0;
2921 		break;
2922 
2923 	case REQ_OVL_MODE:
2924 		cur->overlay = 1;
2925 		break;
2926 
2927 	case REQ_INS_MODE:
2928 		cur->overlay = 0;
2929 		break;
2930 
2931 	case REQ_SCR_FLINE:
2932 		_formi_scroll_fwd(cur, 1);
2933 		break;
2934 
2935 	case REQ_SCR_BLINE:
2936 		_formi_scroll_back(cur, 1);
2937 		break;
2938 
2939 	case REQ_SCR_FPAGE:
2940 		_formi_scroll_fwd(cur, cur->rows);
2941 		break;
2942 
2943 	case REQ_SCR_BPAGE:
2944 		_formi_scroll_back(cur, cur->rows);
2945 		break;
2946 
2947 	case REQ_SCR_FHPAGE:
2948 		_formi_scroll_fwd(cur, cur->rows / 2);
2949 		break;
2950 
2951 	case REQ_SCR_BHPAGE:
2952 		_formi_scroll_back(cur, cur->rows / 2);
2953 		break;
2954 
2955 	case REQ_SCR_FCHAR:
2956 		_formi_hscroll_fwd(cur, row, 1);
2957 		break;
2958 
2959 	case REQ_SCR_BCHAR:
2960 		_formi_hscroll_back(cur, row, 1);
2961 		break;
2962 
2963 	case REQ_SCR_HFLINE:
2964 		_formi_hscroll_fwd(cur, row, cur->cols);
2965 		break;
2966 
2967 	case REQ_SCR_HBLINE:
2968 		_formi_hscroll_back(cur, row, cur->cols);
2969 		break;
2970 
2971 	case REQ_SCR_HFHALF:
2972 		_formi_hscroll_fwd(cur, row, cur->cols / 2);
2973 		break;
2974 
2975 	case REQ_SCR_HBHALF:
2976 		_formi_hscroll_back(cur, row, cur->cols / 2);
2977 		break;
2978 
2979 	default:
2980 		return 0;
2981 	}
2982 
2983 #ifdef DEBUG
2984 	fprintf(dbg,
2985 	 "exit: cursor_xpos=%d, row_xpos=%d, start_char=%d, length=%d, allocated=%d\n",
2986 		cur->cursor_xpos, cur->row_xpos, cur->start_char,
2987 		cur->cur_line->length,	cur->cur_line->allocated);
2988 	fprintf(dbg, "exit: start_line=%p, ypos=%d\n", cur->start_line,
2989 		cur->cursor_ypos);
2990 	fprintf(dbg, "exit: string=\"%s\"\n", cur->cur_line->string);
2991 	assert ((cur->cursor_xpos < INT_MAX) && (cur->row_xpos < INT_MAX)
2992 		&& (cur->cursor_xpos >= cur->row_xpos));
2993 #endif
2994 	return 1;
2995 }
2996 
2997 /*
2998  * Validate the given character by passing it to any type character
2999  * checking routines, if they exist.
3000  */
3001 int
3002 _formi_validate_char(FIELD *field, char c)
3003 {
3004 	int ret_val;
3005 
3006 	if (field->type == NULL)
3007 		return E_OK;
3008 
3009 	ret_val = E_INVALID_FIELD;
3010 	_formi_do_char_validation(field, field->type, c, &ret_val);
3011 
3012 	return ret_val;
3013 }
3014 
3015 
3016 /*
3017  * Perform the validation of the character, invoke all field_type validation
3018  * routines.  If the field is ok then update ret_val to E_OK otherwise
3019  * ret_val is not changed.
3020  */
3021 static void
3022 _formi_do_char_validation(FIELD *field, FIELDTYPE *type, char c, int *ret_val)
3023 {
3024 	if ((type->flags & _TYPE_IS_LINKED) == _TYPE_IS_LINKED) {
3025 		_formi_do_char_validation(field, type->link->next, c, ret_val);
3026 		_formi_do_char_validation(field, type->link->prev, c, ret_val);
3027 	} else {
3028 		if (type->char_check == NULL)
3029 			*ret_val = E_OK;
3030 		else {
3031 			if (type->char_check((int)(unsigned char) c,
3032 					     field->args) == TRUE)
3033 				*ret_val = E_OK;
3034 		}
3035 	}
3036 }
3037 
3038 /*
3039  * Validate the current field.  If the field validation returns success then
3040  * return E_OK otherwise return E_INVALID_FIELD.
3041  *
3042  */
3043 int
3044 _formi_validate_field(FORM *form)
3045 {
3046 	FIELD *cur;
3047 	int ret_val, count;
3048 
3049 
3050 	if ((form == NULL) || (form->fields == NULL) ||
3051 	    (form->fields[0] == NULL))
3052 		return E_INVALID_FIELD;
3053 
3054 	cur = form->fields[form->cur_field];
3055 
3056 	  /*
3057 	   * Sync the buffer if it has been modified so the field
3058 	   * validation routines can use it and because this is
3059 	   * the correct behaviour according to AT&T implementation.
3060 	   */
3061 	if ((cur->buf0_status == TRUE)
3062 	    && ((ret_val = _formi_sync_buffer(cur)) != E_OK))
3063 			return ret_val;
3064 
3065 	  /*
3066 	   * If buffer is untouched then the string pointer may be
3067 	   * NULL, see if this is ok or not.
3068 	   */
3069 	if (cur->buffers[0].string == NULL) {
3070 		if ((cur->opts & O_NULLOK) == O_NULLOK)
3071 			return E_OK;
3072 		else
3073 			return E_INVALID_FIELD;
3074 	}
3075 
3076 	count = _formi_skip_blanks(cur->buffers[0].string, 0);
3077 
3078 	  /* check if we have a null field, depending on the nullok flag
3079 	   * this may be acceptable or not....
3080 	   */
3081 	if (cur->buffers[0].string[count] == '\0') {
3082 		if ((cur->opts & O_NULLOK) == O_NULLOK)
3083 			return E_OK;
3084 		else
3085 			return E_INVALID_FIELD;
3086 	}
3087 
3088 	  /* check if an unmodified field is ok */
3089 	if (cur->buf0_status == 0) {
3090 		if ((cur->opts & O_PASSOK) == O_PASSOK)
3091 			return E_OK;
3092 		else
3093 			return E_INVALID_FIELD;
3094 	}
3095 
3096 	  /* if there is no type then just accept the field */
3097 	if (cur->type == NULL)
3098 		return E_OK;
3099 
3100 	ret_val = E_INVALID_FIELD;
3101 	_formi_do_validation(cur, cur->type, &ret_val);
3102 
3103 	return ret_val;
3104 }
3105 
3106 /*
3107  * Perform the validation of the field, invoke all field_type validation
3108  * routines.  If the field is ok then update ret_val to E_OK otherwise
3109  * ret_val is not changed.
3110  */
3111 static void
3112 _formi_do_validation(FIELD *field, FIELDTYPE *type, int *ret_val)
3113 {
3114 	if ((type->flags & _TYPE_IS_LINKED) == _TYPE_IS_LINKED) {
3115 		_formi_do_validation(field, type->link->next, ret_val);
3116 		_formi_do_validation(field, type->link->prev, ret_val);
3117 	} else {
3118 		if (type->field_check == NULL)
3119 			*ret_val = E_OK;
3120 		else {
3121 			if (type->field_check(field, field_buffer(field, 0))
3122 			    == TRUE)
3123 				*ret_val = E_OK;
3124 		}
3125 	}
3126 }
3127 
3128 /*
3129  * Select the next/previous choice for the field, the driver command
3130  * selecting the direction will be passed in c.  Return 1 if a choice
3131  * selection succeeded, 0 otherwise.
3132  */
3133 int
3134 _formi_field_choice(FORM *form, int c)
3135 {
3136 	FIELDTYPE *type;
3137 	FIELD *field;
3138 
3139 	if ((form == NULL) || (form->fields == NULL) ||
3140 	    (form->fields[0] == NULL) ||
3141 	    (form->fields[form->cur_field]->type == NULL))
3142 		return 0;
3143 
3144 	field = form->fields[form->cur_field];
3145 	type = field->type;
3146 
3147 	switch (c) {
3148 	case REQ_NEXT_CHOICE:
3149 		if (type->next_choice == NULL)
3150 			return 0;
3151 		else
3152 			return type->next_choice(field,
3153 						 field_buffer(field, 0));
3154 
3155 	case REQ_PREV_CHOICE:
3156 		if (type->prev_choice == NULL)
3157 			return 0;
3158 		else
3159 			return type->prev_choice(field,
3160 						 field_buffer(field, 0));
3161 
3162 	default: /* should never happen! */
3163 		return 0;
3164 	}
3165 }
3166 
3167 /*
3168  * Update the fields if they have changed.  The parameter old has the
3169  * previous current field as the current field may have been updated by
3170  * the driver.  Return 1 if the form page needs updating.
3171  *
3172  */
3173 int
3174 _formi_update_field(FORM *form, int old_field)
3175 {
3176 	int cur, i;
3177 
3178 	cur = form->cur_field;
3179 
3180 	if (old_field != cur) {
3181 		if (!((cur >= form->page_starts[form->page].first) &&
3182 		      (cur <= form->page_starts[form->page].last))) {
3183 			  /* not on same page any more */
3184 			for (i = 0; i < form->max_page; i++) {
3185 				if ((form->page_starts[i].in_use == 1) &&
3186 				    (form->page_starts[i].first <= cur) &&
3187 				    (form->page_starts[i].last >= cur)) {
3188 					form->page = i;
3189 					return 1;
3190 				}
3191 			}
3192 		}
3193 	}
3194 
3195 	_formi_redraw_field(form, old_field);
3196 	_formi_redraw_field(form, form->cur_field);
3197 	return 0;
3198 }
3199 
3200 /*
3201  * Compare function for the field sorting
3202  *
3203  */
3204 static int
3205 field_sort_compare(const void *one, const void *two)
3206 {
3207 	const FIELD *a, *b;
3208 	int tl;
3209 
3210 	  /* LINTED const castaway; we don't modify these! */
3211 	a = (const FIELD *) *((const FIELD **) one);
3212 	b = (const FIELD *) *((const FIELD **) two);
3213 
3214 	if (a == NULL)
3215 		return 1;
3216 
3217 	if (b == NULL)
3218 		return -1;
3219 
3220 	  /*
3221 	   * First check the page, we want the fields sorted by page.
3222 	   *
3223 	   */
3224 	if (a->page != b->page)
3225 		return ((a->page > b->page)? 1 : -1);
3226 
3227 	tl = _formi_top_left(a->parent, a->index, b->index);
3228 
3229 	  /*
3230 	   * sort fields left to right, top to bottom so the top left is
3231 	   * the lesser value....
3232 	   */
3233 	return ((tl == a->index)? -1 : 1);
3234 }
3235 
3236 /*
3237  * Sort the fields in a form ready for driver traversal.
3238  */
3239 void
3240 _formi_sort_fields(FORM *form)
3241 {
3242 	FIELD **sort_area;
3243 	int i;
3244 
3245 	CIRCLEQ_INIT(&form->sorted_fields);
3246 
3247 	if ((sort_area = (FIELD **) malloc(sizeof(FIELD *) * form->field_count))
3248 	    == NULL)
3249 		return;
3250 
3251 	bcopy(form->fields, sort_area,
3252 	      (size_t) (sizeof(FIELD *) * form->field_count));
3253 	qsort(sort_area, (size_t) form->field_count, sizeof(FIELD *),
3254 	      field_sort_compare);
3255 
3256 	for (i = 0; i < form->field_count; i++)
3257 		CIRCLEQ_INSERT_TAIL(&form->sorted_fields, sort_area[i], glue);
3258 
3259 	free(sort_area);
3260 }
3261 
3262 /*
3263  * Set the neighbours for all the fields in the given form.
3264  */
3265 void
3266 _formi_stitch_fields(FORM *form)
3267 {
3268 	int above_row, below_row, end_above, end_below, cur_row, real_end;
3269 	FIELD *cur, *above, *below;
3270 
3271 	  /*
3272 	   * check if the sorted fields circle queue is empty, just
3273 	   * return if it is.
3274 	   */
3275 	if (CIRCLEQ_EMPTY(&form->sorted_fields))
3276 		return;
3277 
3278 	  /* initially nothing is above..... */
3279 	above_row = -1;
3280 	end_above = TRUE;
3281 	above = NULL;
3282 
3283 	  /* set up the first field as the current... */
3284 	cur = CIRCLEQ_FIRST(&form->sorted_fields);
3285 	cur_row = cur->form_row;
3286 
3287 	  /* find the first field on the next row if any */
3288 	below = CIRCLEQ_NEXT(cur, glue);
3289 	below_row = -1;
3290 	end_below = TRUE;
3291 	real_end = TRUE;
3292 	while (below != (void *)&form->sorted_fields) {
3293 		if (below->form_row != cur_row) {
3294 			below_row = below->form_row;
3295 			end_below = FALSE;
3296 			real_end = FALSE;
3297 			break;
3298 		}
3299 		below = CIRCLEQ_NEXT(below, glue);
3300 	}
3301 
3302 	  /* walk the sorted fields, setting the neighbour pointers */
3303 	while (cur != (void *) &form->sorted_fields) {
3304 		if (cur == CIRCLEQ_FIRST(&form->sorted_fields))
3305 			cur->left = NULL;
3306 		else
3307 			cur->left = CIRCLEQ_PREV(cur, glue);
3308 
3309 		if (cur == CIRCLEQ_LAST(&form->sorted_fields))
3310 			cur->right = NULL;
3311 		else
3312 			cur->right = CIRCLEQ_NEXT(cur, glue);
3313 
3314 		if (end_above == TRUE)
3315 			cur->up = NULL;
3316 		else {
3317 			cur->up = above;
3318 			above = CIRCLEQ_NEXT(above, glue);
3319 			if (above_row != above->form_row) {
3320 				end_above = TRUE;
3321 				above_row = above->form_row;
3322 			}
3323 		}
3324 
3325 		if (end_below == TRUE)
3326 			cur->down = NULL;
3327 		else {
3328 			cur->down = below;
3329 			below = CIRCLEQ_NEXT(below, glue);
3330 			if (below == (void *) &form->sorted_fields) {
3331 				end_below = TRUE;
3332 				real_end = TRUE;
3333 			} else if (below_row != below->form_row) {
3334 				end_below = TRUE;
3335 				below_row = below->form_row;
3336 			}
3337 		}
3338 
3339 		cur = CIRCLEQ_NEXT(cur, glue);
3340 		if ((cur != (void *) &form->sorted_fields)
3341 		    && (cur_row != cur->form_row)) {
3342 			cur_row = cur->form_row;
3343 			if (end_above == FALSE) {
3344 				for (; above != CIRCLEQ_FIRST(&form->sorted_fields);
3345 				     above = CIRCLEQ_NEXT(above, glue)) {
3346 					if (above->form_row != above_row) {
3347 						above_row = above->form_row;
3348 						break;
3349 					}
3350 				}
3351 			} else if (above == NULL) {
3352 				above = CIRCLEQ_FIRST(&form->sorted_fields);
3353 				end_above = FALSE;
3354 				above_row = above->form_row;
3355 			} else
3356 				end_above = FALSE;
3357 
3358 			if (end_below == FALSE) {
3359 				while (below_row == below->form_row) {
3360 					below = CIRCLEQ_NEXT(below,
3361 							     glue);
3362 					if (below ==
3363 					    (void *)&form->sorted_fields) {
3364 						real_end = TRUE;
3365 						end_below = TRUE;
3366 						break;
3367 					}
3368 				}
3369 
3370 				if (below != (void *)&form->sorted_fields)
3371 					below_row = below->form_row;
3372 			} else if (real_end == FALSE)
3373 				end_below = FALSE;
3374 
3375 		}
3376 	}
3377 }
3378 
3379 /*
3380  * Calculate the length of the displayed line allowing for any tab
3381  * characters that need to be expanded.  We assume that the tab stops
3382  * are 8 characters apart.  The parameters start and end are the
3383  * character positions in the string str we want to get the length of,
3384  * the function returns the number of characters from the start
3385  * position to the end position that should be displayed after any
3386  * intervening tabs have been expanded.
3387  */
3388 int
3389 _formi_tab_expanded_length(char *str, unsigned int start, unsigned int end)
3390 {
3391 	int len, start_len, i;
3392 
3393 	  /* if we have a null string then there is no length */
3394 	if (str[0] == '\0')
3395 		return 0;
3396 
3397 	len = 0;
3398 	start_len = 0;
3399 
3400 	  /*
3401 	   * preceding tabs affect the length tabs in the span, so
3402 	   * we need to calculate the length including the stuff before
3403 	   * start and then subtract off the unwanted bit.
3404 	   */
3405 	for (i = 0; i <= end; i++) {
3406 		if (i == start) /* stash preamble length for later */
3407 			start_len = len;
3408 
3409 		if (str[i] == '\0')
3410 			break;
3411 
3412 		if (str[i] == '\t')
3413 			len = len - (len % 8) + 8;
3414 		else
3415 			len++;
3416 	}
3417 
3418 #ifdef DEBUG
3419 	if (dbg != NULL) {
3420 		fprintf(dbg,
3421 		    "tab_expanded: start=%d, end=%d, expanded=%d (diff=%d)\n",
3422 			start, end, (len - start_len), (end - start));
3423 	}
3424 #endif
3425 
3426 	return (len - start_len);
3427 }
3428 
3429 /*
3430  * Calculate the tab stops on a given line in the field and set up
3431  * the tabs list with the results.  We do this by scanning the line for tab
3432  * characters and if one is found, noting the position and the number of
3433  * characters to get to the next tab stop.  This information is kept to
3434  * make manipulating the field (scrolling and so on) easier to handle.
3435  */
3436 void
3437 _formi_calculate_tabs(_FORMI_FIELD_LINES *row)
3438 {
3439 	_formi_tab_t *ts = row->tabs, *old_ts = NULL, **tsp;
3440 	int i, j;
3441 
3442 	  /*
3443 	   * If the line already has tabs then invalidate them by
3444 	   * walking the list and killing the in_use flag.
3445 	   */
3446 	for (; ts != NULL; ts = ts->fwd)
3447 		ts->in_use = FALSE;
3448 
3449 
3450 	  /*
3451 	   * Now look for tabs in the row and record the info...
3452 	   */
3453 	tsp = &row->tabs;
3454 	for (i = 0, j = 0; i < row->length; i++, j++) {
3455 		if (row->string[i] == '\t') {
3456 			if (*tsp == NULL) {
3457 				if ((*tsp = (_formi_tab_t *)
3458 				     malloc(sizeof(_formi_tab_t))) == NULL)
3459 					return;
3460 				(*tsp)->back = old_ts;
3461 				(*tsp)->fwd = NULL;
3462 			}
3463 
3464 			(*tsp)->in_use = TRUE;
3465 			(*tsp)->pos = i;
3466 			(*tsp)->size = 8 - (j % 8);
3467 			j += (*tsp)->size - 1;
3468 			old_ts = *tsp;
3469 			tsp = &(*tsp)->fwd;
3470 		}
3471 	}
3472 }
3473 
3474 /*
3475  * Return the size of the tab padding for a tab character at the given
3476  * position.  Return 1 if there is not a tab char entry matching the
3477  * given location.
3478  */
3479 static int
3480 tab_size(_FORMI_FIELD_LINES *row, unsigned int i)
3481 {
3482 	_formi_tab_t *ts;
3483 
3484 	ts = row->tabs;
3485 	while ((ts != NULL) && (ts->pos != i))
3486 		ts = ts->fwd;
3487 
3488 	if (ts == NULL)
3489 		return 1;
3490 	else
3491 		return ts->size;
3492 }
3493 
3494 /*
3495  * Find the character offset that corresponds to longest tab expanded
3496  * string that will fit into the given window.  Walk the string backwards
3497  * evaluating the sizes of any tabs that are in the string.  Note that
3498  * using this function on a multi-line window will produce undefined
3499  * results - it is really only required for a single row field.
3500  */
3501 static int
3502 tab_fit_window(FIELD *field, unsigned int pos, unsigned int window)
3503 {
3504 	int scroll_amt, i;
3505 	_formi_tab_t *ts;
3506 
3507 	  /* first find the last tab */
3508 	ts = field->alines->tabs;
3509 
3510 	  /*
3511 	   * unless there are no tabs - just return the window size,
3512 	   * if there is enough room, otherwise 0.
3513 	   */
3514 	if (ts == NULL) {
3515 		if (field->alines->length < window)
3516 			return 0;
3517 		else
3518 			return field->alines->length - window + 1;
3519 	}
3520 
3521 	while ((ts->fwd != NULL) && (ts->fwd->in_use == TRUE))
3522 		ts = ts->fwd;
3523 
3524 	  /*
3525 	   * now walk backwards finding the first tab that is to the
3526 	   * left of our starting pos.
3527 	   */
3528 	while ((ts != NULL) && (ts->in_use == TRUE) && (ts->pos > pos))
3529 		ts = ts->back;
3530 
3531 	scroll_amt = 0;
3532 	for (i = pos; i >= 0; i--) {
3533 		if (field->alines->string[i] == '\t') {
3534 			assert((ts != NULL) && (ts->in_use == TRUE));
3535 			if (ts->pos == i) {
3536 				if ((scroll_amt + ts->size) > window) {
3537 					break;
3538 				}
3539 				scroll_amt += ts->size;
3540 				ts = ts->back;
3541 			}
3542 			else
3543 				assert(ts->pos == i);
3544 		} else {
3545 			scroll_amt++;
3546 			if (scroll_amt > window)
3547 				break;
3548 		}
3549 	}
3550 
3551 	return ++i;
3552 }
3553 
3554 /*
3555  * Return the position of the last character that will fit into the
3556  * given width after tabs have been expanded for a given row of a given
3557  * field.
3558  */
3559 static unsigned int
3560 tab_fit_len(_FORMI_FIELD_LINES *row, unsigned int width)
3561 {
3562 	unsigned int pos, len, row_pos;
3563 	_formi_tab_t *ts;
3564 
3565 	ts = row->tabs;
3566 	pos = 0;
3567 	len = 0;
3568 	row_pos = 0;
3569 
3570 	if (width == 0)
3571 		return 0;
3572 
3573 	while ((len < width) && (pos < row->length)) {
3574 		if (row->string[pos] == '\t') {
3575 			assert((ts != NULL) && (ts->in_use == TRUE));
3576 			if (ts->pos == row_pos) {
3577 				if ((len + ts->size) > width)
3578 					break;
3579 				len += ts->size;
3580 				ts = ts->fwd;
3581 			}
3582 			else
3583 				assert(ts->pos == row_pos);
3584 		} else
3585 			len++;
3586 		pos++;
3587 		row_pos++;
3588 	}
3589 
3590 	if (pos > 0)
3591 		pos--;
3592 	return pos;
3593 }
3594 
3595 /*
3596  * Sync the field line structures with the contents of buffer 0 for that
3597  * field.  We do this by walking all the line structures and concatenating
3598  * all the strings into one single string in buffer 0.
3599  */
3600 int
3601 _formi_sync_buffer(FIELD *field)
3602 {
3603 	_FORMI_FIELD_LINES *line;
3604 	char *nstr, *tmp;
3605 	unsigned length;
3606 
3607 	if (field->alines == NULL)
3608 		return E_BAD_ARGUMENT;
3609 
3610 	if (field->alines->string == NULL)
3611 		return E_BAD_ARGUMENT;
3612 
3613 	  /*
3614 	   * init nstr up front, just in case there are no line contents,
3615 	   * this could happen if the field just contains hard returns.
3616 	   */
3617 	if ((nstr = malloc(sizeof(char))) == NULL)
3618 		return E_SYSTEM_ERROR;
3619 	nstr[0] = '\0';
3620 
3621 	line = field->alines;
3622 	length = 1; /* allow for terminating null */
3623 
3624 	while (line != NULL) {
3625 		if (line->length != 0) {
3626 			if ((tmp = realloc(nstr,
3627 					   (size_t) (length + line->length)))
3628 			    == NULL) {
3629 				if (nstr != NULL)
3630 					free(nstr);
3631 				return (E_SYSTEM_ERROR);
3632 			}
3633 
3634 			nstr = tmp;
3635 			strcat(nstr, line->string);
3636 			length += line->length;
3637 		}
3638 
3639 		line = line->next;
3640 	}
3641 
3642 	if (field->buffers[0].string != NULL)
3643 		free(field->buffers[0].string);
3644 	field->buffers[0].allocated = length;
3645 	field->buffers[0].length = length - 1;
3646 	field->buffers[0].string = nstr;
3647 	return E_OK;
3648 }
3649 
3650 
3651 
3652