xref: /netbsd-src/lib/libform/internals.c (revision e55cffd8e520e9b03f18a1bd98bb04223e79f69f)
1 /*	$NetBSD: internals.c,v 1.14 2001/04/06 05:03:22 blymn 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 withough 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 <ctype.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <strings.h>
36 #include "internals.h"
37 #include "form.h"
38 
39 #ifdef DEBUG
40 /*
41  *  file handle to write debug info to, this will be initialised when
42  *  the form is first posted.
43  */
44 FILE *dbg = NULL;
45 #endif
46 
47 /* define our own min function - this is not generic but will do here
48  * (don't believe me?  think about what value you would get
49  * from min(x++, y++)
50  */
51 #define min(a,b) (((a) > (b))? (b) : (a))
52 
53 /* for the line joining function... */
54 #define JOIN_NEXT    1
55 #define JOIN_NEXT_NW 2 /* next join, don't wrap the joined line */
56 #define JOIN_PREV    3
57 #define JOIN_PREV_NW 4 /* previous join, don't wrap the joined line */
58 
59 static void
60 _formi_do_char_validation(FIELD *field, FIELDTYPE *type, char c, int *ret_val);
61 static void
62 _formi_do_validation(FIELD *field, FIELDTYPE *type, int *ret_val);
63 static int
64 _formi_join_line(FIELD *field, char *str, unsigned int pos, int direction);
65 void
66 _formi_hscroll_back(FIELD *field, unsigned int amt);
67 void
68 _formi_hscroll_fwd(FIELD *field, unsigned int amt);
69 static void
70 _formi_scroll_back(FIELD *field, unsigned int amt);
71 static void
72 _formi_scroll_fwd(FIELD *field, unsigned int amt);
73 static int
74 find_sow(char *str, unsigned int offset);
75 static int
76 find_cur_line(FIELD *cur);
77 
78 /*
79  * Open the debug file if it is not already open....
80  */
81 #ifdef DEBUG
82 int
83 _formi_create_dbg_file(void)
84 {
85 	if (dbg == NULL) {
86 		dbg = fopen("___form_dbg.out", "w");
87 		if (dbg == NULL) {
88 			fprintf(stderr, "Cannot open debug file!\n");
89 			return E_SYSTEM_ERROR;
90 		}
91 	}
92 
93 	return E_OK;
94 }
95 #endif
96 
97 /*
98  * Set the form's current field to the first valid field on the page.
99  * Assume the fields have been sorted and stitched.
100  */
101 int
102 _formi_pos_first_field(FORM *form)
103 {
104 	FIELD *cur;
105 	int old_page;
106 
107 	old_page = form->page;
108 
109 	  /* scan forward for an active page....*/
110 	while (form->page_starts[form->page].in_use == 0) {
111 		form->page++;
112 		if (form->page > form->max_page) {
113 			form->page = old_page;
114 			return E_REQUEST_DENIED;
115 		}
116 	}
117 
118 	  /* then scan for a field we can use */
119 	cur = form->fields[form->page_starts[form->page].first];
120 	while ((cur->opts & (O_VISIBLE | O_ACTIVE))
121 	       != (O_VISIBLE | O_ACTIVE)) {
122 		cur = CIRCLEQ_NEXT(cur, glue);
123 		if (cur == (void *) &form->sorted_fields) {
124 			form->page = old_page;
125 			return E_REQUEST_DENIED;
126 		}
127 	}
128 
129 	form->cur_field = cur->index;
130 	return E_OK;
131 }
132 
133 /*
134  * Set the field to the next active and visible field, the fields are
135  * traversed in index order in the direction given.  If the parameter
136  * use_sorted is TRUE then the sorted field list will be traversed instead
137  * of using the field index.
138  */
139 int
140 _formi_pos_new_field(FORM *form, unsigned direction, unsigned use_sorted)
141 {
142 	FIELD *cur;
143 	int i;
144 
145 	i = form->cur_field;
146 	cur = form->fields[i];
147 
148 	do {
149 		if (direction == _FORMI_FORWARD) {
150 			if (use_sorted == TRUE) {
151 				if ((form->wrap == FALSE) &&
152 				    (cur == CIRCLEQ_LAST(&form->sorted_fields)))
153 					return E_REQUEST_DENIED;
154 				cur = CIRCLEQ_NEXT(cur, glue);
155 				i = cur->index;
156 			} else {
157 				if ((form->wrap == FALSE) &&
158 				    ((i + 1) >= form->field_count))
159 					return E_REQUEST_DENIED;
160 				i++;
161 				if (i >= form->field_count)
162 					i = 0;
163 			}
164 		} else {
165 			if (use_sorted == TRUE) {
166 				if ((form->wrap == FALSE) &&
167 				    (cur == CIRCLEQ_FIRST(&form->sorted_fields)))
168 					return E_REQUEST_DENIED;
169 				cur = CIRCLEQ_PREV(cur, glue);
170 				i = cur->index;
171 			} else {
172 				if ((form->wrap == FALSE) && (i <= 0))
173 					return E_REQUEST_DENIED;
174 				i--;
175 				if (i < 0)
176 					i = form->field_count - 1;
177 			}
178 		}
179 
180 		if ((form->fields[i]->opts & (O_VISIBLE | O_ACTIVE))
181 			== (O_VISIBLE | O_ACTIVE)) {
182 			form->cur_field = i;
183 			return E_OK;
184 		}
185 	}
186 	while (i != form->cur_field);
187 
188 	return E_REQUEST_DENIED;
189 }
190 
191 /*
192  * Find the line in a field that the cursor is currently on.
193  */
194 static int
195 find_cur_line(FIELD *cur)
196 {
197 	unsigned start, end, pos, row;
198 	const char *str;
199 
200 	str = cur->buffers[0].string;
201 	pos = cur->start_char + cur->cursor_xpos;
202 
203 	start = 0;
204 	end = 0;
205 
206 	for (row = 1; row < cur->row_count; row++) {
207 		start = _formi_find_bol(str, start);
208 		end = _formi_find_eol(str, end);
209 		if ((pos >= start) && (pos <= end))
210 			return row;
211 	}
212 
213 	return 0;
214 }
215 
216 
217 /*
218  * Word wrap the contents of the field's buffer 0 if this is allowed.
219  * If the wrap is successful, that is, the row count nor the buffer
220  * size is exceeded then the function will return E_OK, otherwise it
221  * will return E_REQUEST_DENIED.
222  */
223 int
224 _formi_wrap_field(FIELD *field, unsigned int pos)
225 {
226 	char *str, *new;
227 	int width, length, allocated, row_count, sol, eol, wrapped;
228 	size_t new_size;
229 
230 	wrapped = FALSE;
231 	row_count = 0;
232 	allocated = field->buffers[0].allocated;
233 	length = field->buffers[0].length;
234 	if ((str = (char *) malloc(sizeof(char) * allocated)) == NULL)
235 		return E_SYSTEM_ERROR;
236 
237 	strcpy(str,field->buffers[0].string);
238 
239 	if ((field->opts & O_STATIC) == O_STATIC) {
240 		width = field->cols + 1;
241 		if ((field->rows + field->nrows) == 1)
242 			return E_OK; /* cannot wrap a single line */
243 	} else {
244 		if ((field->drows + field->nrows) == 1)
245 			return E_OK;
246 		width = field->dcols;
247 	}
248 
249 	while (str[pos] != '\0') {
250 		row_count++;
251 		sol = _formi_find_bol(str, pos);
252 		eol = _formi_find_eol(str, pos);
253 		if ((eol - sol) <= width) {
254 			  /* line may be too short, try joining some lines */
255 			pos = eol;
256 			if ((eol - sol) == width) {
257 				/* if line is just right then don't wrap */
258 				pos++;
259 				continue;
260 			}
261 
262 			if (_formi_join_line(field, str, pos, JOIN_NEXT_NW)
263 			    == E_OK) {
264 				row_count--; /* cuz we just joined a line */
265 				wrapped = TRUE;
266 			} else
267 				break;
268 		} else {
269 			  /* line is too long, split it - maybe */
270 			  /* split on first whitespace before current word */
271 			pos = sol + width;
272 			if ((!isblank(str[pos])) &&
273 			    ((field->opts & O_WRAP) == O_WRAP))
274 				pos = find_sow(str, pos);
275 
276 			if (pos != sol) {
277 				if (length + 1 >= allocated) {
278 					new_size = allocated + 64
279 						- (allocated % 64);
280 
281 					if ((new = (char *) realloc(str,
282 								    sizeof(char) * new_size)
283 					     ) == NULL) {
284 						free(str);
285 						return E_SYSTEM_ERROR;
286 					}
287 					str = new;
288 					allocated = new_size;
289 				}
290 
291 				bcopy(&str[pos], &str[pos + 1],
292 				      (unsigned) length - pos - 1);
293 				str[pos] = '\n';
294 				pos = pos + 1;
295 				length++;
296 				wrapped = TRUE;
297 			} else
298 				break;
299 		}
300 	}
301 
302 	if (row_count > field->rows) {
303 		free(str);
304 		return E_REQUEST_DENIED;
305 	}
306 
307 	if (wrapped == TRUE) {
308 		field->buffers[0].length = length;
309 		field->buffers[0].allocated = allocated;
310 		free(field->buffers[0].string);
311 		field->buffers[0].string = str;
312 	} else /* all that work was in vain.... */
313 		free(str);
314 
315 	return E_OK;
316 }
317 
318 /*
319  * Join the two lines that surround the location pos, the type
320  * variable indicates the direction of the join.  Note that pos is
321  * assumed to be at either the end of the line for a JOIN_NEXT or at
322  * the beginning of the line for a JOIN_PREV.  We need to check the
323  * field options to ensure the join does not overflow the line limit
324  * (if wrap is off) or wrap the field buffer again.  Returns E_OK if
325  * the join was successful or E_REQUEST_DENIED if the join cannot
326  * happen.
327  */
328 static int
329 _formi_join_line(FIELD *field, char *str, unsigned int pos, int direction)
330 {
331 	unsigned int len, eol, npos, start, dest;
332 
333 	npos = pos;
334 
335 	if ((direction == JOIN_NEXT) || (direction == JOIN_NEXT_NW)) {
336 		npos++;
337 		  /* see if there is another line following... */
338 		if (str[npos] == '\0')
339 			return E_REQUEST_DENIED;
340 		eol = _formi_find_eol(str, npos);
341 
342 		start = npos;
343 		dest = pos;
344 		len = eol - npos;
345 	} else {
346 		if (pos == 0)
347 			return E_REQUEST_DENIED;
348 		eol = _formi_find_eol(str, pos);
349 		npos--;
350 		start = pos;
351 		dest = npos;
352 		len = eol - pos;
353 	}
354 
355 
356 	bcopy(&str[start], &str[dest], (unsigned) len);
357 
358 	  /* wrap the field if required, if this fails undo the change */
359 	if ((direction == JOIN_NEXT) || (direction == JOIN_PREV)) {
360 		if (_formi_wrap_field(field, (unsigned int) pos) != E_OK) {
361 			bcopy(&str[dest], &str[start], (unsigned) len);
362 			str[dest] = '\n';
363 			return E_REQUEST_DENIED;
364 		}
365 	}
366 
367 	return E_OK;
368 }
369 
370 /*
371  * skip the blanks in the given string, start at the index start and
372  * continue forward until either the end of the string or a non-blank
373  * character is found.  Return the index of either the end of the string or
374  * the first non-blank character.
375  */
376 unsigned
377 _formi_skip_blanks(char *string, unsigned int start)
378 {
379 	unsigned int i;
380 
381 	i = start;
382 
383 	while ((string[i] != '\0') && isblank(string[i]))
384 		i++;
385 
386 	return i;
387 }
388 
389 /*
390  * Return the index of the top left most field of the two given fields.
391  */
392 static int
393 _formi_top_left(FORM *form, int a, int b)
394 {
395 	  /* lower row numbers always win here.... */
396 	if (form->fields[a]->form_row < form->fields[b]->form_row)
397 		return a;
398 
399 	if (form->fields[a]->form_row > form->fields[b]->form_row)
400 		return b;
401 
402 	  /* rows must be equal, check columns */
403 	if (form->fields[a]->form_col < form->fields[b]->form_col)
404 		return a;
405 
406 	if (form->fields[a]->form_col > form->fields[b]->form_col)
407 		return b;
408 
409 	  /* if we get here fields must be in exactly the same place, punt */
410 	return a;
411 }
412 
413 /*
414  * Return the index to the field that is the bottom-right-most of the
415  * two given fields.
416  */
417 static int
418 _formi_bottom_right(FORM *form, int a, int b)
419 {
420 	  /* check the rows first, biggest row wins */
421 	if (form->fields[a]->form_row > form->fields[b]->form_row)
422 		return a;
423 	if (form->fields[a]->form_row < form->fields[b]->form_row)
424 		return b;
425 
426 	  /* rows must be equal, check cols, biggest wins */
427 	if (form->fields[a]->form_col > form->fields[b]->form_col)
428 		return a;
429 	if (form->fields[a]->form_col < form->fields[b]->form_col)
430 		return b;
431 
432 	  /* fields in the same place, punt */
433 	return a;
434 }
435 
436 /*
437  * Find the next '\n' character in the given string starting at offset
438  * if there are no newlines found then return the index to the end of the
439  * string.
440  */
441 int
442 _formi_find_eol(const char *string, unsigned int offset)
443 {
444 	char *location;
445 	int eol;
446 
447 	if ((location = index(&string[offset], '\n')) != NULL)
448 		eol  = location - string;
449 	else
450 		eol = strlen(string);
451 
452 	if (eol > 0)
453 		eol--;
454 
455 	return eol;
456 }
457 
458 /*
459  * Find the previous '\n' character in the given string starting at offset
460  * if there are no newlines found then return 0.
461  */
462 int
463 _formi_find_bol(const char *string, unsigned int offset)
464 {
465 	int cnt;
466 
467 	cnt = offset;
468 	while ((cnt > 0) && (string[cnt] != '\n'))
469 		cnt--;
470 
471 	  /* if we moved and found a newline go forward one to point at the
472 	   * actual start of the line....
473 	   */
474 	if ((cnt != offset) && (string[cnt] == '\n'))
475 		cnt++;
476 
477 	return cnt;
478 }
479 
480 /*
481  * Find the end of the current word in the string str, starting at
482  * offset - the end includes any trailing whitespace.  If the end of
483  * the string is found before a new word then just return the offset
484  * to the end of the string.
485  */
486 static int
487 find_eow(char *str, unsigned int offset)
488 {
489 	int start;
490 
491 	start = offset;
492 	  /* first skip any non-whitespace */
493 	while ((str[start] != '\0') && !isblank(str[start]))
494 		start++;
495 
496 	  /* see if we hit the end of the string */
497 	if (str[start] == '\0')
498 		return start;
499 
500 	  /* otherwise skip the whitespace.... */
501 	while ((str[start] != '\0') && isblank(str[start]))
502 		start++;
503 
504 	return start;
505 }
506 
507 /*
508  * Find the beginning of the current word in the string str, starting
509  * at offset.
510  */
511 static int
512 find_sow(char *str, unsigned int offset)
513 {
514 	int start;
515 
516 	start = offset;
517 
518 	if (start > 0) {
519 		if (isblank(str[start]) || isblank(str[start - 1])) {
520 			if (isblank(str[start - 1]))
521 				start--;
522 			  /* skip the whitespace.... */
523 			while ((start >= 0) && isblank(str[start]))
524 				start--;
525 		}
526 	}
527 
528 	  /* see if we hit the start of the string */
529 	if (start < 0)
530 		return 0;
531 
532 	  /* now skip any non-whitespace */
533 	while ((start >= 0) && !isblank(str[start]))
534 		start--;
535 
536 	if (start > 0)
537 		start++; /* last loop has us pointing at a space, adjust */
538 
539 	if (start < 0)
540 		start = 0;
541 
542 	return start;
543 }
544 
545 /*
546  * Scroll the field forward the given number of lines.
547  */
548 static void
549 _formi_scroll_fwd(FIELD *field, unsigned int amt)
550 {
551 	  /* check if we have lines to scroll */
552 	if (field->row_count < (field->start_line + field->rows))
553 		return;
554 
555 	field->start_line += min(amt,
556 				 field->row_count - field->start_line
557 				 - field->rows);
558 }
559 
560 /*
561  * Scroll the field backward the given number of lines.
562  */
563 static void
564 _formi_scroll_back(FIELD *field, unsigned int amt)
565 {
566 	if (field->start_line == 0)
567 		return;
568 
569 	field->start_line -= min(field->start_line, amt);
570 }
571 
572 /*
573  * Scroll the field forward the given number of characters.
574  */
575 void
576 _formi_hscroll_fwd(FIELD *field, int unsigned amt)
577 {
578 	int end, scroll_amt;
579 
580 	end = _formi_find_eol(field->buffers[0].string,
581 		       field->start_char + field->cursor_xpos)
582 		- field->start_char - field->cursor_xpos;
583 
584 	scroll_amt = min(amt, end);
585 	if (scroll_amt < 0)
586 		scroll_amt = 0;
587 
588 	field->start_char += scroll_amt;
589 }
590 
591 /*
592  * Scroll the field backward the given number of characters.
593  */
594 void
595 _formi_hscroll_back(FIELD *field, unsigned int amt)
596 {
597 	field->start_char -= min(field->start_char, amt);
598 }
599 
600 /*
601  * Find the different pages in the form fields and assign the form
602  * page_starts array with the information to find them.
603  */
604 int
605 _formi_find_pages(FORM *form)
606 {
607 	int i, cur_page = 0;
608 
609 	if ((form->page_starts = (_FORMI_PAGE_START *)
610 	     malloc((form->max_page + 1) * sizeof(_FORMI_PAGE_START))) == NULL)
611 		return E_SYSTEM_ERROR;
612 
613 	  /* initialise the page starts array */
614 	memset(form->page_starts, 0,
615 	       (form->max_page + 1) * sizeof(_FORMI_PAGE_START));
616 
617 	for (i =0; i < form->field_count; i++) {
618 		if (form->fields[i]->page_break == 1)
619 			cur_page++;
620 		if (form->page_starts[cur_page].in_use == 0) {
621 			form->page_starts[cur_page].in_use = 1;
622 			form->page_starts[cur_page].first = i;
623 			form->page_starts[cur_page].last = i;
624 			form->page_starts[cur_page].top_left = i;
625 			form->page_starts[cur_page].bottom_right = i;
626 		} else {
627 			form->page_starts[cur_page].last = i;
628 			form->page_starts[cur_page].top_left =
629 				_formi_top_left(form,
630 						form->page_starts[cur_page].top_left,
631 						i);
632 			form->page_starts[cur_page].bottom_right =
633 				_formi_bottom_right(form,
634 						    form->page_starts[cur_page].bottom_right,
635 						    i);
636 		}
637 	}
638 
639 	return E_OK;
640 }
641 
642 /*
643  * Completely redraw the field of the given form.
644  */
645 void
646 _formi_redraw_field(FORM *form, int field)
647 {
648 	unsigned int pre, post, flen, slen, i, row, start, end;
649 	char *str;
650 	FIELD *cur;
651 #ifdef DEBUG
652 	char buffer[100];
653 #endif
654 
655 	cur = form->fields[field];
656 	str = cur->buffers[0].string;
657 	flen = cur->cols;
658 	slen = 0;
659 	start = 0;
660 	end = 0;
661 
662 	wmove(form->scrwin, (int) cur->form_row, (int) cur->form_col);
663 	for (row = 1; row <= cur->row_count; row++) {
664 		if (str == NULL) {
665 			start = end = 0;
666 		} else {
667 			if ((str[end] == '\0') || (str[end + 1] == '\0')
668 			    || (row == 1))
669 				start = end;
670 			else
671 				start = end + 1;
672 		}
673 
674 		if (cur->buffers[0].length > 0) {
675 			end = _formi_find_eol(str, start);
676 			slen = end - start + 1;
677 		} else
678 			slen = 0;
679 
680 		if ((cur->opts & O_STATIC) == O_STATIC) {
681 			switch (cur->justification) {
682 			case JUSTIFY_RIGHT:
683 				post = 0;
684 				if (flen < slen)
685 					pre = 0;
686 				else
687 					pre = flen - slen;
688 				break;
689 
690 			case JUSTIFY_CENTER:
691 				if (flen < slen) {
692 					pre = 0;
693 					post = 0;
694 				} else {
695 					pre = flen - slen;
696 					post = pre = pre / 2;
697 					  /* get padding right if
698                                              centring is not even */
699 					if ((post + pre + slen) < flen)
700 						post++;
701 				}
702 				break;
703 
704 			case NO_JUSTIFICATION:
705 			case JUSTIFY_LEFT:
706 			default:
707 				pre = 0;
708 				if (flen <= slen)
709 					post = 0;
710 				else {
711 					post = flen - slen;
712 					if (post > flen)
713 						post = flen;
714 				}
715 				break;
716 			}
717 		} else {
718 			  /* dynamic fields are not justified */
719 			pre = 0;
720 			if (flen <= slen)
721 				post = 0;
722 			else {
723 				post = flen - slen;
724 				if (post > flen)
725 					post = flen;
726 			}
727 
728 			  /* but they do scroll.... */
729 
730 			if (pre > cur->start_char - start)
731 				pre = pre - cur->start_char + start;
732 			else
733 				pre = 0;
734 
735 			if (slen > cur->start_char) {
736 				slen -= cur->start_char;
737 				post += cur->start_char;
738 				if (post > flen)
739 					post = flen;
740 			} else {
741 				slen = 0;
742 				post = flen - pre;
743 			}
744 		}
745 
746 		if (form->cur_field == field)
747 			wattrset(form->scrwin, cur->fore);
748 		else
749 			wattrset(form->scrwin, cur->back);
750 
751 #ifdef DEBUG
752 		if (_formi_create_dbg_file() == E_OK) {
753 			fprintf(dbg,
754   "redraw_field: start=%d, pre=%d, slen=%d, flen=%d, post=%d, start_char=%d\n",
755 				start, pre, slen, flen, post, cur->start_char);
756 			if (str != NULL) {
757 				strncpy(buffer, &str[cur->start_char], flen);
758 			} else {
759 				strcpy(buffer, "(null)");
760 			}
761 			buffer[flen] = '\0';
762 			fprintf(dbg, "redraw_field: %s\n", buffer);
763 		}
764 #endif
765 
766 		for (i = start + cur->start_char; i < pre; i++)
767 			waddch(form->scrwin, cur->pad);
768 
769 #ifdef DEBUG
770 		fprintf(dbg, "redraw_field: will add %d chars\n",
771 			min(slen, flen));
772 #endif
773 		for (i = 0; i < min(slen, flen); i++)
774 		{
775 #ifdef DEBUG
776 			fprintf(dbg, "adding char str[%d]=%c\n",
777 				i + cur->start_char, str[i + cur->start_char]);
778 #endif
779 			if (((cur->opts & O_PUBLIC) != O_PUBLIC)) {
780 				waddch(form->scrwin, cur->pad);
781 			} else if ((cur->opts & O_VISIBLE) == O_VISIBLE) {
782 				waddch(form->scrwin, str[i + cur->start_char]);
783 			} else {
784 				waddch(form->scrwin, ' ');
785 			}
786 		}
787 
788 		for (i = 0; i < post; i++)
789 			waddch(form->scrwin, cur->pad);
790 	}
791 
792 	return;
793 }
794 
795 /*
796  * Display the fields attached to the form that are on the current page
797  * on the screen.
798  *
799  */
800 int
801 _formi_draw_page(FORM *form)
802 {
803 	int i;
804 
805 	if (form->page_starts[form->page].in_use == 0)
806 		return E_BAD_ARGUMENT;
807 
808 	wclear(form->scrwin);
809 
810 	for (i = form->page_starts[form->page].first;
811 	     i <= form->page_starts[form->page].last; i++)
812 		_formi_redraw_field(form, i);
813 
814 	return E_OK;
815 }
816 
817 /*
818  * Add the character c at the position pos in buffer 0 of the given field
819  */
820 int
821 _formi_add_char(FIELD *field, unsigned int pos, char c)
822 {
823 	char *new;
824 	unsigned int new_size;
825 	int status;
826 
827 	  /*
828 	   * If buffer has not had a string before, set it to a blank
829 	   * string.  Everything should flow from there....
830 	   */
831 	if (field->buffers[0].string == NULL) {
832 		set_field_buffer(field, 0, "");
833 	}
834 
835 	if (_formi_validate_char(field, c) != E_OK) {
836 #ifdef DEBUG
837 		fprintf(dbg, "add_char: char %c failed char validation\n", c);
838 #endif
839 		return E_INVALID_FIELD;
840 	}
841 
842 #ifdef DEBUG
843 	fprintf(dbg, "add_char: pos=%d, char=%c\n", pos, c);
844 	fprintf(dbg,
845 	   "add_char enter: xpos=%d, start=%d, length=%d(%d), allocated=%d\n",
846 		field->cursor_xpos, field->start_char,
847 		field->buffers[0].length, strlen(field->buffers[0].string),
848 		field->buffers[0].allocated);
849 	fprintf(dbg, "add_char enter: %s\n", field->buffers[0].string);
850 	fprintf(dbg, "add_char enter: buf0_status=%d\n", field->buf0_status);
851 #endif
852 	if (((field->opts & O_BLANK) == O_BLANK) &&
853 	    (field->buf0_status == FALSE) &&
854 	    ((field->cursor_xpos + field->start_char) == 0)) {
855 		field->buffers[0].length = 0;
856 		field->buffers[0].string[0] = '\0';
857 		pos = 0;
858 		field->start_char = 0;
859 		field->start_line = 0;
860 		field->row_count = 1;
861 		field->cursor_xpos = 0;
862 		field->cursor_ypos = 0;
863 	}
864 
865 
866 	if ((field->overlay == 0)
867 	    || ((field->overlay == 1) && (pos >= field->buffers[0].length))) {
868 		  /* first check if the field can have more chars...*/
869 		if ((((field->opts & O_STATIC) == O_STATIC) &&
870 		     (field->buffers[0].length >= field->cols)) ||
871 		    (((field->opts & O_STATIC) != O_STATIC) &&
872 /*XXXXX this is wrong - should check max row or col */		     ((field->max > 0) &&
873 		      (field->buffers[0].length >= field->max))))
874 			return E_REQUEST_DENIED;
875 
876 		if (field->buffers[0].length + 1
877 		    >= field->buffers[0].allocated) {
878 			new_size = field->buffers[0].allocated + 64
879 				- (field->buffers[0].allocated % 64);
880 			if ((new = (char *) realloc(field->buffers[0].string,
881 						    new_size )) == NULL)
882 				return E_SYSTEM_ERROR;
883 			field->buffers[0].allocated = new_size;
884 			field->buffers[0].string = new;
885 		}
886 	}
887 
888 	if ((field->overlay == 0) && (field->buffers[0].length > pos)) {
889 		bcopy(&field->buffers[0].string[pos],
890 		      &field->buffers[0].string[pos + 1],
891 		      field->buffers[0].length - pos + 1);
892 	}
893 
894 	field->buffers[0].string[pos] = c;
895 	if (pos >= field->buffers[0].length) {
896 		  /* make sure the string is terminated if we are at the
897 		   * end of the string, the terminator would be missing
898 		   * if we are are at the end of the field.
899 		   */
900 		field->buffers[0].string[pos + 1] = '\0';
901 	}
902 
903 	  /* only increment the length if we are inserting characters
904 	   * OR if we are at the end of the field in overlay mode.
905 	   */
906 	if ((field->overlay == 0)
907 	    || ((field->overlay == 1) && (pos >= field->buffers[0].length)))
908 			field->buffers[0].length++;
909 
910 	  /* wrap the field, if needed */
911 	status = _formi_wrap_field(field, pos);
912 	if (status != E_OK) {
913 		  /* wrap failed for some reason, back out the char insert */
914 		bcopy(&field->buffers[0].string[pos + 1],
915 		      &field->buffers[0].string[pos],
916 		      field->buffers[0].length - pos);
917 		field->buffers[0].length--;
918 	} else {
919 		field->buf0_status = TRUE;
920 
921 		if ((field->cursor_xpos < (field->cols - 1)) ||
922 		    ((field->opts & O_STATIC) != O_STATIC))
923 			field->cursor_xpos++;
924 
925 		if (field->cursor_xpos > field->cols) {
926 			field->start_char++;
927 			field->cursor_xpos = field->cols;
928 		}
929 	}
930 
931 #ifdef DEBUG
932 	fprintf(dbg,
933 	    "add_char exit: xpos=%d, start=%d, length=%d(%d), allocated=%d\n",
934 		field->cursor_xpos, field->start_char,
935 		field->buffers[0].length, strlen(field->buffers[0].string),
936 		field->buffers[0].allocated);
937 	fprintf(dbg,"add_char exit: %s\n", field->buffers[0].string);
938 	fprintf(dbg, "add_char exit: buf0_status=%d\n", field->buf0_status);
939 	fprintf(dbg, "add_char exit: status = %s\n",
940 		(status == E_OK)? "OK" : "FAILED");
941 #endif
942 	return status;
943 }
944 
945 /*
946  * Manipulate the text in a field, this takes the given form and performs
947  * the passed driver command on the current text field.  Returns 1 if the
948  * text field was modified.
949  */
950 int
951 _formi_manipulate_field(FORM *form, int c)
952 {
953 	FIELD *cur;
954 	char *str;
955 	unsigned int i, start, end, pos;
956 
957 	cur = form->fields[form->cur_field];
958 
959 #ifdef DEBUG
960 	fprintf(dbg,
961 		"entry: xpos=%d, start_char=%d, length=%d, allocated=%d\n",
962 		cur->cursor_xpos, cur->start_char, cur->buffers[0].length,
963 		cur->buffers[0].allocated);
964 	fprintf(dbg, "entry: string=");
965 	if (cur->buffers[0].string == NULL)
966 		fprintf(dbg, "(null)\n");
967 	else
968 		fprintf(dbg, "\"%s\"\n", cur->buffers[0].string);
969 #endif
970 
971 	  /* Cannot manipulate a null string! */
972 	if (cur->buffers[0].string == NULL)
973 		return E_REQUEST_DENIED;
974 
975 	switch (c) {
976 	case REQ_NEXT_CHAR:
977 		  /* for a dynamic field allow an offset of one more
978 		   * char so we can insert chars after end of string.
979 		   * Static fields cannot do this so deny request if
980 		   * cursor is at the end of the field.
981 		   */
982 		if (((cur->opts & O_STATIC) == O_STATIC) &&
983 		    (cur->cursor_xpos == cur->cols - 1))
984 			return E_REQUEST_DENIED;
985 
986 		if ((cur->cursor_xpos + cur->start_char + 1)
987 		    > cur->buffers[0].length)
988 			return E_REQUEST_DENIED;
989 
990 		cur->cursor_xpos++;
991 		if (cur->cursor_xpos >= cur->cols - 1) {
992 			cur->cursor_xpos = cur->cols - 1;
993 			if ((cur->opts & O_STATIC) != O_STATIC)
994 				cur->start_char++;
995 		}
996 		break;
997 
998 	case REQ_PREV_CHAR:
999 		if (cur->cursor_xpos == 0) {
1000 			if (cur->start_char > 0)
1001 				cur->start_char--;
1002 			else
1003 				return E_REQUEST_DENIED;
1004 		} else
1005 			cur->cursor_xpos--;
1006 		break;
1007 
1008 	case REQ_NEXT_LINE:
1009 		cur->cursor_ypos++;
1010 		if (cur->cursor_ypos > cur->rows) {
1011 			if ((cur->opts & O_STATIC) == O_STATIC) {
1012 				if (cur->start_line + cur->cursor_ypos
1013 				    > cur->drows) {
1014 					cur->cursor_ypos--;
1015 					return E_REQUEST_DENIED;
1016 				}
1017 			} else {
1018 				if (cur->start_line + cur->cursor_ypos
1019 				    > cur->nrows + cur->rows) {
1020 					cur->cursor_ypos--;
1021 					return E_REQUEST_DENIED;
1022 				}
1023 			}
1024 			cur->start_line++;
1025 		}
1026 		break;
1027 
1028 	case REQ_PREV_LINE:
1029 		if (cur->cursor_ypos == 0) {
1030 			if (cur->start_line == 0)
1031 				return E_REQUEST_DENIED;
1032 			cur->start_line--;
1033 		} else
1034 			cur->cursor_ypos--;
1035 		break;
1036 
1037 	case REQ_NEXT_WORD:
1038 		start = cur->start_char + cur->cursor_xpos;
1039 		str = cur->buffers[0].string;
1040 
1041 		start = find_eow(str, start);
1042 
1043 		  /* check if we hit the end */
1044 		if (str[start] == '\0')
1045 			return E_REQUEST_DENIED;
1046 
1047 		  /* otherwise we must have found the start of a word...*/
1048 		if (start - cur->start_char < cur->cols) {
1049 			cur->cursor_xpos = start;
1050 		} else {
1051 			cur->start_char = start;
1052 			cur->cursor_xpos = 0;
1053 		}
1054 		break;
1055 
1056 	case REQ_PREV_WORD:
1057 		start = cur->start_char + cur->cursor_xpos;
1058 		if (cur->start_char > 0)
1059 			start--;
1060 
1061 		if (start == 0)
1062 			return E_REQUEST_DENIED;
1063 
1064 		str = cur->buffers[0].string;
1065 
1066 		start = find_sow(str, start);
1067 
1068 		if (start - cur->start_char > 0) {
1069 			cur->cursor_xpos = start;
1070 		} else {
1071 			cur->start_char = start;
1072 			cur->cursor_xpos = 0;
1073 		}
1074 		break;
1075 
1076 	case REQ_BEG_FIELD:
1077 		cur->start_char = 0;
1078 		cur->start_line = 0;
1079 		cur->cursor_xpos = 0;
1080 		cur->cursor_ypos = 0;
1081 		break;
1082 
1083 	case REQ_BEG_LINE:
1084 		start = cur->start_char + cur->cursor_xpos;
1085 		if (cur->buffers[0].string[start] == '\n') {
1086 			if (start > 0)
1087 				start--;
1088 			else
1089 				return E_REQUEST_DENIED;
1090 		}
1091 
1092 		while ((start > 0)
1093 		       && (cur->buffers[0].string[start] != '\n'))
1094 			start--;
1095 
1096 		if (start > 0)
1097 			start++;
1098 
1099 		cur->start_char = start;
1100 		cur->cursor_xpos = 0;
1101 		break;
1102 
1103 	case REQ_END_FIELD:
1104 		if (cur->row_count > cur->rows) {
1105 			cur->start_line = cur->row_count - cur->rows;
1106 			cur->cursor_ypos = cur->rows - 1;
1107 		} else {
1108 			cur->start_line = 0;
1109 			cur->cursor_ypos = cur->row_count - 1;
1110 		}
1111 
1112 		if ((str = rindex(cur->buffers[0].string, '\n')) == NULL) {
1113 			cur->start_char = 0;
1114 
1115 		} else {
1116 			cur->start_char = (str - cur->buffers[0].string) + 1;
1117 		}
1118 
1119 		cur->cursor_xpos = 0;
1120 		  /* we fall through here deliberately, we are on the
1121 		   * correct row, now we need to get to the end of the
1122 		   * line.
1123 		   */
1124 		  /* FALLTHRU */
1125 
1126 	case REQ_END_LINE:
1127 		start = cur->start_char + cur->cursor_xpos;
1128 		end = _formi_find_eol(cur->buffers[0].string, start);
1129 		start = _formi_find_bol(cur->buffers[0].string, start);
1130 
1131 		if (end - start > cur->cols - 1) {
1132 			cur->cursor_xpos = cur->cols - 1;
1133 			cur->start_char = end - cur->cols;
1134 			if ((cur->opts & O_STATIC) != O_STATIC)
1135 				cur->start_char++;
1136 		} else {
1137 			cur->cursor_xpos = end - start + 1;
1138 			if (((cur->opts & O_STATIC) == O_STATIC) &&
1139 			    ((end - start) == (cur->cols - 1)))
1140 				cur->cursor_xpos--;
1141 
1142 			cur->start_char = start;
1143 		}
1144 		break;
1145 
1146 	case REQ_LEFT_CHAR:
1147 		if ((cur->cursor_xpos == 0) && (cur->start_char == 0))
1148 			return E_REQUEST_DENIED;
1149 
1150 		if (cur->cursor_xpos == 0) {
1151 			cur->start_char--;
1152 			if (cur->buffers[0].string[cur->start_char] == '\n') {
1153 				if ((cur->cursor_ypos == 0) &&
1154 				    (cur->start_line == 0))
1155 				{
1156 					cur->start_char++;
1157 					return E_REQUEST_DENIED;
1158 				}
1159 
1160 				if (cur->cursor_ypos == 0)
1161 					cur->start_line--;
1162 				else
1163 					cur->cursor_ypos--;
1164 
1165 				end = _formi_find_eol(cur->buffers[0].string,
1166 					       cur->start_char);
1167 				start = _formi_find_bol(cur->buffers[0].string,
1168 						 cur->start_char);
1169 				if (end - start >= cur->cols) {
1170 					cur->cursor_xpos = cur->cols - 1;
1171 					cur->start_char = end - cur->cols;
1172 				} else {
1173 					cur->cursor_xpos = end - start;
1174 					cur->start_char = start;
1175 				}
1176 			}
1177 		} else
1178 			cur->cursor_xpos--;
1179 		break;
1180 
1181 	case REQ_RIGHT_CHAR:
1182 		pos = cur->start_char + cur->cursor_xpos;
1183 		if (cur->buffers[0].string[pos] == '\0')
1184 			return E_REQUEST_DENIED;
1185 
1186 #ifdef DEBUG
1187 		fprintf(dbg, "req_right_char enter: start=%d, xpos=%d, c=%c\n",
1188 			cur->start_char, cur->cursor_xpos,
1189 			cur->buffers[0].string[pos]);
1190 #endif
1191 
1192 		if (cur->buffers[0].string[pos] == '\n') {
1193 			start = pos + 1;
1194 			if (cur->buffers[0].string[start] == 0)
1195 				return E_REQUEST_DENIED;
1196 			end = _formi_find_eol(cur->buffers[0].string, start);
1197 			if (end - start > cur->cols) {
1198 				cur->cursor_xpos = cur->cols - 1;
1199 				cur->start_char = end - cur->cols - 1;
1200 			} else {
1201 				cur->cursor_xpos = end - start;
1202 				cur->start_char = start;
1203 			}
1204 		} else {
1205 			if (cur->cursor_xpos == cur->cols - 1)
1206 				cur->start_char++;
1207 			else
1208 				cur->cursor_xpos++;
1209 		}
1210 #ifdef DEBUG
1211 		fprintf(dbg, "req_right_char exit: start=%d, xpos=%d, c=%c\n",
1212 			cur->start_char, cur->cursor_xpos,
1213 			cur->buffers[0].string[cur->start_char +
1214 					      cur->cursor_xpos]);
1215 #endif
1216 		break;
1217 
1218 	case REQ_UP_CHAR:
1219 		if (cur->cursor_ypos == 0) {
1220 			if (cur->start_line == 0)
1221 				return E_REQUEST_DENIED;
1222 
1223 			cur->start_line--;
1224 		} else
1225 			cur->cursor_ypos--;
1226 
1227 		start = find_cur_line(cur);
1228 		end = _formi_find_eol(cur->buffers[0].string, start);
1229 		cur->start_char = start;
1230 		if (cur->cursor_xpos > end - start)
1231 			cur->cursor_xpos = end - start;
1232 		break;
1233 
1234 	case REQ_DOWN_CHAR:
1235 		if (cur->cursor_ypos == cur->rows - 1) {
1236 			if (cur->start_line + cur->rows == cur->row_count)
1237 				return E_REQUEST_DENIED;
1238 			cur->start_line++;
1239 		} else
1240 			cur->cursor_ypos++;
1241 
1242 		start = find_cur_line(cur);
1243 		end = _formi_find_eol(cur->buffers[0].string, start);
1244 		cur->start_char = start;
1245 		if (cur->cursor_xpos > end - start)
1246 			cur->cursor_xpos = end - start;
1247 		break;
1248 
1249 	case REQ_NEW_LINE:
1250 		if (_formi_add_char(cur, cur->start_char + cur->cursor_xpos,
1251 				    '\n') == E_OK)
1252 			cur->row_count++;
1253 		break;
1254 
1255 	case REQ_INS_CHAR:
1256 		_formi_add_char(cur, cur->start_char + cur->cursor_xpos,
1257 				cur->pad);
1258 		break;
1259 
1260 	case REQ_INS_LINE:
1261 		start = _formi_find_bol(cur->buffers[0].string, cur->start_char);
1262 		if (_formi_add_char(cur, start, '\n') == E_OK)
1263 			cur->row_count++;
1264 		break;
1265 
1266 	case REQ_DEL_CHAR:
1267 		if (cur->buffers[0].string[cur->start_char + cur->cursor_xpos]
1268 		    == '\0')
1269 			return E_REQUEST_DENIED;
1270 
1271 		start = cur->start_char + cur->cursor_xpos;
1272 		end = cur->buffers[0].length;
1273 		if (cur->buffers[0].string[start] == '\n') {
1274 			if (cur->row_count > 1) {
1275 				cur->row_count--;
1276 				_formi_join_line(cur, cur->buffers[0].string,
1277 						 start, JOIN_NEXT);
1278 			} else
1279 				cur->buffers[0].string[start] = '\0';
1280 		} else {
1281 			bcopy(&cur->buffers[0].string[start + 1],
1282 			      &cur->buffers[0].string[start],
1283 			      (unsigned) end - start + 1);
1284 		}
1285 
1286 		cur->buffers[0].length--;
1287 		break;
1288 
1289 	case REQ_DEL_PREV:
1290 		if ((cur->cursor_xpos == 0) && (cur->start_char == 0))
1291 			   return E_REQUEST_DENIED;
1292 
1293 		start = cur->cursor_xpos + cur->start_char;
1294 		end = cur->buffers[0].length;
1295 
1296 		if (cur->buffers[0].string[cur->start_char + cur->cursor_xpos] == '\n') {
1297 			_formi_join_line(cur, cur->buffers[0].string,
1298 					 cur->start_char + cur->cursor_xpos,
1299 					 JOIN_PREV);
1300 			cur->row_count--;
1301 		} else {
1302 			bcopy(&cur->buffers[0].string[start],
1303 			      &cur->buffers[0].string[start - 1],
1304 			      (unsigned) end - start + 1);
1305 		}
1306 
1307 		cur->buffers[0].length--;
1308 		if ((cur->cursor_xpos == 0) && (cur->start_char > 0))
1309 			cur->start_char--;
1310 		else if ((cur->cursor_xpos == cur->cols - 1)
1311 			 && (cur->start_char > 0))
1312 			cur->start_char--;
1313 		else if (cur->cursor_xpos > 0)
1314 			cur->cursor_xpos--;
1315 
1316 		break;
1317 
1318 	case REQ_DEL_LINE:
1319 		start = cur->start_char + cur->cursor_xpos;
1320 		end = _formi_find_eol(cur->buffers[0].string, start);
1321 		start = _formi_find_bol(cur->buffers[0].string, start);
1322 		bcopy(&cur->buffers[0].string[end + 1],
1323 		      &cur->buffers[0].string[start],
1324 		      (unsigned) cur->buffers[0].length - end + 1);
1325 		if (cur->row_count > 1)
1326 			cur->row_count--;
1327 		break;
1328 
1329 	case REQ_DEL_WORD:
1330 		start = cur->start_char + cur->cursor_xpos;
1331 		end = find_eow(cur->buffers[0].string, start);
1332 		start = find_sow(cur->buffers[0].string, start);
1333 		bcopy(&cur->buffers[0].string[end + 1],
1334 		      &cur->buffers[0].string[start],
1335 		      (unsigned) cur->buffers[0].length - end + 1);
1336 		cur->buffers[0].length -= end - start;
1337 		break;
1338 
1339 	case REQ_CLR_EOL:
1340 		  /*XXXX this right or should we just toast the chars? */
1341 		start = cur->start_char + cur->cursor_xpos;
1342 		end = _formi_find_eol(cur->buffers[0].string, start);
1343 		for (i = start; i < end; i++)
1344 			cur->buffers[0].string[i] = cur->pad;
1345 		break;
1346 
1347 	case REQ_CLR_EOF:
1348 		for (i = cur->start_char + cur->cursor_xpos;
1349 		     i < cur->buffers[0].length; i++)
1350 			cur->buffers[0].string[i] = cur->pad;
1351 		break;
1352 
1353 	case REQ_CLR_FIELD:
1354 		for (i = 0; i < cur->buffers[0].length; i++)
1355 			cur->buffers[0].string[i] = cur->pad;
1356 		break;
1357 
1358 	case REQ_OVL_MODE:
1359 		cur->overlay = 1;
1360 		break;
1361 
1362 	case REQ_INS_MODE:
1363 		cur->overlay = 0;
1364 		break;
1365 
1366 	case REQ_SCR_FLINE:
1367 		_formi_scroll_fwd(cur, 1);
1368 		break;
1369 
1370 	case REQ_SCR_BLINE:
1371 		_formi_scroll_back(cur, 1);
1372 		break;
1373 
1374 	case REQ_SCR_FPAGE:
1375 		_formi_scroll_fwd(cur, cur->rows);
1376 		break;
1377 
1378 	case REQ_SCR_BPAGE:
1379 		_formi_scroll_back(cur, cur->rows);
1380 		break;
1381 
1382 	case REQ_SCR_FHPAGE:
1383 		_formi_scroll_fwd(cur, cur->rows / 2);
1384 		break;
1385 
1386 	case REQ_SCR_BHPAGE:
1387 		_formi_scroll_back(cur, cur->rows / 2);
1388 		break;
1389 
1390 	case REQ_SCR_FCHAR:
1391 		_formi_hscroll_fwd(cur, 1);
1392 		break;
1393 
1394 	case REQ_SCR_BCHAR:
1395 		_formi_hscroll_back(cur, 1);
1396 		break;
1397 
1398 	case REQ_SCR_HFLINE:
1399 		_formi_hscroll_fwd(cur, cur->cols);
1400 		break;
1401 
1402 	case REQ_SCR_HBLINE:
1403 		_formi_hscroll_back(cur, cur->cols);
1404 		break;
1405 
1406 	case REQ_SCR_HFHALF:
1407 		_formi_hscroll_fwd(cur, cur->cols / 2);
1408 		break;
1409 
1410 	case REQ_SCR_HBHALF:
1411 		_formi_hscroll_back(cur, cur->cols / 2);
1412 		break;
1413 
1414 	default:
1415 		return 0;
1416 	}
1417 
1418 #ifdef DEBUG
1419 	fprintf(dbg, "exit: xpos=%d, start_char=%d, length=%d, allocated=%d\n",
1420 		cur->cursor_xpos, cur->start_char, cur->buffers[0].length,
1421 		cur->buffers[0].allocated);
1422 	fprintf(dbg, "exit: string=\"%s\"\n", cur->buffers[0].string);
1423 #endif
1424 	return 1;
1425 }
1426 
1427 /*
1428  * Validate the give character by passing it to any type character
1429  * checking routines, if they exist.
1430  */
1431 int
1432 _formi_validate_char(FIELD *field, char c)
1433 {
1434 	int ret_val;
1435 
1436 	if (field->type == NULL)
1437 		return E_OK;
1438 
1439 	ret_val = E_INVALID_FIELD;
1440 	_formi_do_char_validation(field, field->type, c, &ret_val);
1441 
1442 	return ret_val;
1443 }
1444 
1445 
1446 /*
1447  * Perform the validation of the character, invoke all field_type validation
1448  * routines.  If the field is ok then update ret_val to E_OK otherwise
1449  * ret_val is not changed.
1450  */
1451 static void
1452 _formi_do_char_validation(FIELD *field, FIELDTYPE *type, char c, int *ret_val)
1453 {
1454 	if ((type->flags & _TYPE_IS_LINKED) == _TYPE_IS_LINKED) {
1455 		_formi_do_char_validation(field, type->link->next, c, ret_val);
1456 		_formi_do_char_validation(field, type->link->prev, c, ret_val);
1457 	} else {
1458 		if (type->char_check == NULL)
1459 			*ret_val = E_OK;
1460 		else {
1461 			if (type->char_check((int)(unsigned char) c,
1462 					     field->args) == TRUE)
1463 				*ret_val = E_OK;
1464 		}
1465 	}
1466 }
1467 
1468 /*
1469  * Validate the current field.  If the field validation returns success then
1470  * return E_OK otherwise return E_INVALID_FIELD.
1471  *
1472  */
1473 int
1474 _formi_validate_field(FORM *form)
1475 {
1476 	FIELD *cur;
1477 	char *bp;
1478 	int ret_val, count;
1479 
1480 
1481 	if ((form == NULL) || (form->fields == NULL) ||
1482 	    (form->fields[0] == NULL))
1483 		return E_INVALID_FIELD;
1484 
1485 	cur = form->fields[form->cur_field];
1486 
1487 	bp = cur->buffers[0].string;
1488 	count = _formi_skip_blanks(bp, 0);
1489 
1490 	  /* check if we have a null field, depending on the nullok flag
1491 	   * this may be acceptable or not....
1492 	   */
1493 	if (cur->buffers[0].string[count] == '\0') {
1494 		if ((cur->opts & O_NULLOK) == O_NULLOK)
1495 			return E_OK;
1496 		else
1497 			return E_INVALID_FIELD;
1498 	}
1499 
1500 	  /* check if an unmodified field is ok */
1501 	if (cur->buf0_status == 0) {
1502 		if ((cur->opts & O_PASSOK) == O_PASSOK)
1503 			return E_OK;
1504 		else
1505 			return E_INVALID_FIELD;
1506 	}
1507 
1508 	  /* if there is no type then just accept the field */
1509 	if (cur->type == NULL)
1510 		return E_OK;
1511 
1512 	ret_val = E_INVALID_FIELD;
1513 	_formi_do_validation(cur, cur->type, &ret_val);
1514 
1515 	return ret_val;
1516 }
1517 
1518 /*
1519  * Perform the validation of the field, invoke all field_type validation
1520  * routines.  If the field is ok then update ret_val to E_OK otherwise
1521  * ret_val is not changed.
1522  */
1523 static void
1524 _formi_do_validation(FIELD *field, FIELDTYPE *type, int *ret_val)
1525 {
1526 	if ((type->flags & _TYPE_IS_LINKED) == _TYPE_IS_LINKED) {
1527 		_formi_do_validation(field, type->link->next, ret_val);
1528 		_formi_do_validation(field, type->link->prev, ret_val);
1529 	} else {
1530 		if (type->field_check == NULL)
1531 			*ret_val = E_OK;
1532 		else {
1533 			if (type->field_check(field, field_buffer(field, 0))
1534 			    == TRUE)
1535 				*ret_val = E_OK;
1536 		}
1537 	}
1538 }
1539 
1540 /*
1541  * Select the next/previous choice for the field, the driver command
1542  * selecting the direction will be passed in c.  Return 1 if a choice
1543  * selection succeeded, 0 otherwise.
1544  */
1545 int
1546 _formi_field_choice(FORM *form, int c)
1547 {
1548 	FIELDTYPE *type;
1549 	FIELD *field;
1550 
1551 	if ((form == NULL) || (form->fields == NULL) ||
1552 	    (form->fields[0] == NULL) ||
1553 	    (form->fields[form->cur_field]->type == NULL))
1554 		return 0;
1555 
1556 	field = form->fields[form->cur_field];
1557 	type = field->type;
1558 
1559 	switch (c) {
1560 	case REQ_NEXT_CHOICE:
1561 		if (type->next_choice == NULL)
1562 			return 0;
1563 		else
1564 			return type->next_choice(field,
1565 						 field_buffer(field, 0));
1566 
1567 	case REQ_PREV_CHOICE:
1568 		if (type->prev_choice == NULL)
1569 			return 0;
1570 		else
1571 			return type->prev_choice(field,
1572 						 field_buffer(field, 0));
1573 
1574 	default: /* should never happen! */
1575 		return 0;
1576 	}
1577 }
1578 
1579 /*
1580  * Update the fields if they have changed.  The parameter old has the
1581  * previous current field as the current field may have been updated by
1582  * the driver.  Return 1 if the form page needs updating.
1583  *
1584  */
1585 int
1586 _formi_update_field(FORM *form, int old_field)
1587 {
1588 	int cur, i;
1589 
1590 	cur = form->cur_field;
1591 
1592 	if (old_field != cur) {
1593 		if (!((cur >= form->page_starts[form->page].first) &&
1594 		      (cur <= form->page_starts[form->page].last))) {
1595 			  /* not on same page any more */
1596 			for (i = 0; i < form->max_page; i++) {
1597 				if ((form->page_starts[i].in_use == 1) &&
1598 				    (form->page_starts[i].first <= cur) &&
1599 				    (form->page_starts[i].last >= cur)) {
1600 					form->page = i;
1601 					return 1;
1602 				}
1603 			}
1604 		}
1605 	}
1606 
1607 	_formi_redraw_field(form, old_field);
1608 	_formi_redraw_field(form, form->cur_field);
1609 	return 0;
1610 }
1611 
1612 /*
1613  * Compare function for the field sorting
1614  *
1615  */
1616 static int
1617 field_sort_compare(const void *one, const void *two)
1618 {
1619 	const FIELD *a, *b;
1620 	int tl;
1621 
1622 	  /* LINTED const castaway; we don't modify these! */
1623 	a = (const FIELD *) *((const FIELD **) one);
1624 	b = (const FIELD *) *((const FIELD **) two);
1625 
1626 	if (a == NULL)
1627 		return 1;
1628 
1629 	if (b == NULL)
1630 		return -1;
1631 
1632 	  /*
1633 	   * First check the page, we want the fields sorted by page.
1634 	   *
1635 	   */
1636 	if (a->page != b->page)
1637 		return ((a->page > b->page)? 1 : -1);
1638 
1639 	tl = _formi_top_left(a->parent, a->index, b->index);
1640 
1641 	  /*
1642 	   * sort fields left to right, top to bottom so the top left is
1643 	   * the less than value....
1644 	   */
1645 	return ((tl == a->index)? -1 : 1);
1646 }
1647 
1648 /*
1649  * Sort the fields in a form ready for driver traversal.
1650  */
1651 void
1652 _formi_sort_fields(FORM *form)
1653 {
1654 	FIELD **sort_area;
1655 	int i;
1656 
1657 	CIRCLEQ_INIT(&form->sorted_fields);
1658 
1659 	if ((sort_area = (FIELD **) malloc(sizeof(FIELD *) * form->field_count))
1660 	    == NULL)
1661 		return;
1662 
1663 	bcopy(form->fields, sort_area, sizeof(FIELD *) * form->field_count);
1664 	qsort(sort_area, (unsigned) form->field_count, sizeof(FIELD *),
1665 	      field_sort_compare);
1666 
1667 	for (i = 0; i < form->field_count; i++)
1668 		CIRCLEQ_INSERT_TAIL(&form->sorted_fields, sort_area[i], glue);
1669 
1670 	free(sort_area);
1671 }
1672 
1673 /*
1674  * Set the neighbours for all the fields in the given form.
1675  */
1676 void
1677 _formi_stitch_fields(FORM *form)
1678 {
1679 	int above_row, below_row, end_above, end_below, cur_row, real_end;
1680 	FIELD *cur, *above, *below;
1681 
1682 	  /*
1683 	   * check if the sorted fields circle queue is empty, just
1684 	   * return if it is.
1685 	   */
1686 	if (CIRCLEQ_EMPTY(&form->sorted_fields))
1687 		return;
1688 
1689 	  /* initially nothing is above..... */
1690 	above_row = -1;
1691 	end_above = TRUE;
1692 	above = NULL;
1693 
1694 	  /* set up the first field as the current... */
1695 	cur = CIRCLEQ_FIRST(&form->sorted_fields);
1696 	cur_row = cur->form_row;
1697 
1698 	  /* find the first field on the next row if any */
1699 	below = CIRCLEQ_NEXT(cur, glue);
1700 	below_row = -1;
1701 	end_below = TRUE;
1702 	real_end = TRUE;
1703 	while (below != (void *)&form->sorted_fields) {
1704 		if (below->form_row != cur_row) {
1705 			below_row = below->form_row;
1706 			end_below = FALSE;
1707 			real_end = FALSE;
1708 			break;
1709 		}
1710 		below = CIRCLEQ_NEXT(below, glue);
1711 	}
1712 
1713 	  /* walk the sorted fields, setting the neighbour pointers */
1714 	while (cur != (void *) &form->sorted_fields) {
1715 		if (cur == CIRCLEQ_FIRST(&form->sorted_fields))
1716 			cur->left = NULL;
1717 		else
1718 			cur->left = CIRCLEQ_PREV(cur, glue);
1719 
1720 		if (cur == CIRCLEQ_LAST(&form->sorted_fields))
1721 			cur->right = NULL;
1722 		else
1723 			cur->right = CIRCLEQ_NEXT(cur, glue);
1724 
1725 		if (end_above == TRUE)
1726 			cur->up = NULL;
1727 		else {
1728 			cur->up = above;
1729 			above = CIRCLEQ_NEXT(above, glue);
1730 			if (above_row != above->form_row) {
1731 				end_above = TRUE;
1732 				above_row = above->form_row;
1733 			}
1734 		}
1735 
1736 		if (end_below == TRUE)
1737 			cur->down = NULL;
1738 		else {
1739 			cur->down = below;
1740 			below = CIRCLEQ_NEXT(below, glue);
1741 			if (below == (void *) &form->sorted_fields) {
1742 				end_below = TRUE;
1743 				real_end = TRUE;
1744 			} else if (below_row != below->form_row) {
1745 				end_below = TRUE;
1746 				below_row = below->form_row;
1747 			}
1748 		}
1749 
1750 		cur = CIRCLEQ_NEXT(cur, glue);
1751 		if ((cur != (void *) &form->sorted_fields)
1752 		    && (cur_row != cur->form_row)) {
1753 			cur_row = cur->form_row;
1754 			if (end_above == FALSE) {
1755 				for (; above != CIRCLEQ_FIRST(&form->sorted_fields);
1756 				     above = CIRCLEQ_NEXT(above, glue)) {
1757 					if (above->form_row != above_row) {
1758 						above_row = above->form_row;
1759 						break;
1760 					}
1761 				}
1762 			} else if (above == NULL) {
1763 				above = CIRCLEQ_FIRST(&form->sorted_fields);
1764 				end_above = FALSE;
1765 				above_row = above->form_row;
1766 			} else
1767 				end_above = FALSE;
1768 
1769 			if (end_below == FALSE) {
1770 				while (below_row == below->form_row) {
1771 					below = CIRCLEQ_NEXT(below,
1772 							     glue);
1773 					if (below ==
1774 					    (void *)&form->sorted_fields) {
1775 						real_end = TRUE;
1776 						end_below = TRUE;
1777 						break;
1778 					}
1779 				}
1780 
1781 				if (below != (void *)&form->sorted_fields)
1782 					below_row = below->form_row;
1783 			} else if (real_end == FALSE)
1784 				end_below = FALSE;
1785 
1786 		}
1787 	}
1788 }
1789