xref: /netbsd-src/lib/libform/internals.c (revision 3cec974c61d7fac0a37c0377723a33214a458c8b)
1 /*	$NetBSD: internals.c,v 1.12 2001/02/15 05:21:26 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 	cur = form->fields[form->page_starts[form->page].first];
119 	while ((cur->opts & (O_VISIBLE | O_ACTIVE))
120 	       != (O_VISIBLE | O_ACTIVE)) {
121 		cur = CIRCLEQ_NEXT(cur, glue);
122 		if (cur == (void *) &form->sorted_fields) {
123 			form->page = old_page;
124 			return E_REQUEST_DENIED;
125 		}
126 	}
127 
128 	form->cur_field = cur->index;
129 	return E_OK;
130 }
131 
132 /*
133  * Set the field to the next active and visible field, the fields are
134  * traversed in index order in the direction given.  If the parameter
135  * use_sorted is TRUE then the sorted field list will be traversed instead
136  * of using the field index.
137  */
138 int
139 _formi_pos_new_field(FORM *form, unsigned direction, unsigned use_sorted)
140 {
141 	FIELD *cur;
142 	int i;
143 
144 	i = form->cur_field;
145 	cur = form->fields[i];
146 
147 	do {
148 		if (direction == _FORMI_FORWARD) {
149 			if (use_sorted == TRUE) {
150 				if ((form->wrap == FALSE) &&
151 				    (cur == CIRCLEQ_LAST(&form->sorted_fields)))
152 					return E_REQUEST_DENIED;
153 				cur = CIRCLEQ_NEXT(cur, glue);
154 				i = cur->index;
155 			} else {
156 				if ((form->wrap == FALSE) &&
157 				    ((i + 1) >= form->field_count))
158 					return E_REQUEST_DENIED;
159 				i++;
160 				if (i >= form->field_count)
161 					i = 0;
162 			}
163 		} else {
164 			if (use_sorted == TRUE) {
165 				if ((form->wrap == FALSE) &&
166 				    (cur == CIRCLEQ_FIRST(&form->sorted_fields)))
167 					return E_REQUEST_DENIED;
168 				cur = CIRCLEQ_PREV(cur, glue);
169 				i = cur->index;
170 			} else {
171 				if ((form->wrap == FALSE) && (i <= 0))
172 					return E_REQUEST_DENIED;
173 				i--;
174 				if (i < 0)
175 					i = form->field_count - 1;
176 			}
177 		}
178 
179 		if ((form->fields[i]->opts & (O_VISIBLE | O_ACTIVE))
180 			== (O_VISIBLE | O_ACTIVE)) {
181 			form->cur_field = i;
182 			return E_OK;
183 		}
184 	}
185 	while (i != form->cur_field);
186 
187 	return E_REQUEST_DENIED;
188 }
189 
190 /*
191  * Find the line in a field that the cursor is currently on.
192  */
193 static int
194 find_cur_line(FIELD *cur)
195 {
196 	unsigned start, end, pos, row;
197 	const char *str;
198 
199 	str = cur->buffers[0].string;
200 	pos = cur->start_char + cur->hscroll + cur->cursor_xpos;
201 
202 	start = 0;
203 	end = 0;
204 
205 	for (row = 1; row < cur->row_count; row++) {
206 		start = _formi_find_bol(str, start);
207 		end = _formi_find_eol(str, end);
208 		if ((pos >= start) && (pos <= end))
209 			return row;
210 	}
211 
212 	return 0;
213 }
214 
215 
216 /*
217  * Word wrap the contents of the field's buffer 0 if this is allowed.
218  * If the wrap is successful, that is, the row count nor the buffer
219  * size is exceeded then the function will return E_OK, otherwise it
220  * will return E_REQUEST_DENIED.
221  */
222 int
223 _formi_wrap_field(FIELD *field, unsigned int pos)
224 {
225 	char *str, *new;
226 	int width, length, allocated, row_count, sol, eol, wrapped;
227 	size_t new_size;
228 
229 	wrapped = FALSE;
230 	row_count = 0;
231 	allocated = field->buffers[0].allocated;
232 	length = field->buffers[0].length;
233 	if ((str = (char *) malloc(sizeof(char) * allocated)) == NULL)
234 		return E_SYSTEM_ERROR;
235 
236 	strcpy(str,field->buffers[0].string);
237 
238 	if ((field->opts & O_STATIC) == O_STATIC) {
239 		width = field->cols + 1;
240 		if ((field->rows + field->nrows) == 1)
241 			return E_OK; /* cannot wrap a single line */
242 	} else {
243 		if ((field->drows + field->nrows) == 1)
244 			return E_OK;
245 		width = field->dcols;
246 	}
247 
248 	while (str[pos] != '\0') {
249 		row_count++;
250 		sol = _formi_find_bol(str, pos);
251 		eol = _formi_find_eol(str, pos);
252 		if ((eol - sol) <= width) {
253 			  /* line may be too short, try joining some lines */
254 			pos = eol;
255 			if ((eol - sol) == width) {
256 				/* if line is just right then don't wrap */
257 				pos++;
258 				continue;
259 			}
260 
261 			if (_formi_join_line(field, str, pos, JOIN_NEXT_NW)
262 			    == E_OK) {
263 				row_count--; /* cuz we just joined a line */
264 				wrapped = TRUE;
265 			} else
266 				break;
267 		} else {
268 			  /* line is too long, split it - maybe */
269 			  /* split on first whitespace before current word */
270 			pos = sol + width;
271 			if (!isblank(str[pos]))
272 				pos = find_sow(str, pos);
273 
274 			if (pos != sol) {
275 				if (length + 1 >= allocated) {
276 					new_size = allocated + 64
277 						- (allocated % 64);
278 
279 					if ((new = (char *) realloc(str,
280 								    sizeof(char) * new_size)
281 					     ) == NULL) {
282 						free(str);
283 						return E_SYSTEM_ERROR;
284 					}
285 					str = new;
286 					allocated = new_size;
287 				}
288 
289 				bcopy(&str[pos], &str[pos + 1],
290 				      (unsigned) length - pos - 1);
291 				str[pos] = '\n';
292 				pos = pos + 1;
293 				length++;
294 				wrapped = TRUE;
295 			} else
296 				break;
297 		}
298 	}
299 
300 	if (row_count > field->rows) {
301 		free(str);
302 		return E_REQUEST_DENIED;
303 	}
304 
305 	if (wrapped == TRUE) {
306 		field->buffers[0].length = length;
307 		field->buffers[0].allocated = allocated;
308 		free(field->buffers[0].string);
309 		field->buffers[0].string = str;
310 	} else /* all that work was in vain.... */
311 		free(str);
312 
313 	return E_OK;
314 }
315 
316 /*
317  * Join the two lines that surround the location pos, the type
318  * variable indicates the direction of the join.  Note that pos is
319  * assumed to be at either the end of the line for a JOIN_NEXT or at
320  * the beginning of the line for a JOIN_PREV.  We need to check the
321  * field options to ensure the join does not overflow the line limit
322  * (if wrap is off) or wrap the field buffer again.  Returns E_OK if
323  * the join was successful or E_REQUEST_DENIED if the join cannot
324  * happen.
325  */
326 static int
327 _formi_join_line(FIELD *field, char *str, unsigned int pos, int direction)
328 {
329 	unsigned int len, sol, eol, npos, start, dest;
330 
331 	npos = pos;
332 
333 	if ((direction == JOIN_NEXT) || (direction == JOIN_NEXT_NW)) {
334 		sol = _formi_find_bol(str, pos);
335 		npos++;
336 		  /* see if there is another line following... */
337 		if (str[npos] == '\0')
338 			return E_REQUEST_DENIED;
339 		eol = _formi_find_eol(str, npos);
340 
341 		start = npos;
342 		dest = pos;
343 		len = eol - npos;
344 	} else {
345 		if (pos == 0)
346 			return E_REQUEST_DENIED;
347 		eol = _formi_find_eol(str, pos);
348 		npos--;
349 		sol = _formi_find_bol(str, npos);
350 
351 		start = pos;
352 		dest = npos;
353 		len = eol - pos;
354 	}
355 
356 
357 	  /* if we cannot wrap and the length of the resultant line
358 	   * is bigger than our field width we shall deny the request.
359 	   */
360 	if (((field->opts & O_WRAP) != O_WRAP) && /* XXXXX check for dynamic field */
361 	    ((sol + eol - 1) > field->cols))
362 		return E_REQUEST_DENIED;
363 
364 	bcopy(&str[start], &str[dest], (unsigned) len);
365 
366 	  /* wrap the field if required, if this fails undo the change */
367 	if ((direction == JOIN_NEXT) || (direction == JOIN_PREV)) {
368 		if (_formi_wrap_field(field, (unsigned int) pos) != E_OK) {
369 			bcopy(&str[dest], &str[start], (unsigned) len);
370 			str[dest] = '\n';
371 			return E_REQUEST_DENIED;
372 		}
373 	}
374 
375 	return E_OK;
376 }
377 
378 /*
379  * skip the blanks in the given string, start at the index start and
380  * continue forward until either the end of the string or a non-blank
381  * character is found.  Return the index of either the end of the string or
382  * the first non-blank character.
383  */
384 unsigned
385 _formi_skip_blanks(char *string, unsigned int start)
386 {
387 	unsigned int i;
388 
389 	i = start;
390 
391 	while ((string[i] != '\0') && isblank(string[i]))
392 		i++;
393 
394 	return i;
395 }
396 
397 /*
398  * Return the index of the top left most field of the two given fields.
399  */
400 static int
401 _formi_top_left(FORM *form, int a, int b)
402 {
403 	  /* lower row numbers always win here.... */
404 	if (form->fields[a]->form_row < form->fields[b]->form_row)
405 		return a;
406 
407 	if (form->fields[a]->form_row > form->fields[b]->form_row)
408 		return b;
409 
410 	  /* rows must be equal, check columns */
411 	if (form->fields[a]->form_col < form->fields[b]->form_col)
412 		return a;
413 
414 	if (form->fields[a]->form_col > form->fields[b]->form_col)
415 		return b;
416 
417 	  /* if we get here fields must be in exactly the same place, punt */
418 	return a;
419 }
420 
421 /*
422  * Return the index to the field that is the bottom-right-most of the
423  * two given fields.
424  */
425 static int
426 _formi_bottom_right(FORM *form, int a, int b)
427 {
428 	  /* check the rows first, biggest row wins */
429 	if (form->fields[a]->form_row > form->fields[b]->form_row)
430 		return a;
431 	if (form->fields[a]->form_row < form->fields[b]->form_row)
432 		return b;
433 
434 	  /* rows must be equal, check cols, biggest wins */
435 	if (form->fields[a]->form_col > form->fields[b]->form_col)
436 		return a;
437 	if (form->fields[a]->form_col < form->fields[b]->form_col)
438 		return b;
439 
440 	  /* fields in the same place, punt */
441 	return a;
442 }
443 
444 /*
445  * Find the next '\n' character in the given string starting at offset
446  * if there are no newlines found then return the index to the end of the
447  * string.
448  */
449 int
450 _formi_find_eol(const char *string, unsigned int offset)
451 {
452 	char *location;
453 	int eol;
454 
455 	if ((location = index(&string[offset], '\n')) != NULL)
456 		eol  = location - string;
457 	else
458 		eol = strlen(string);
459 
460 	if (eol > 0)
461 		eol--;
462 
463 	return eol;
464 }
465 
466 /*
467  * Find the previous '\n' character in the given string starting at offset
468  * if there are no newlines found then return 0.
469  */
470 int
471 _formi_find_bol(const char *string, unsigned int offset)
472 {
473 	int cnt;
474 
475 	cnt = offset;
476 	while ((cnt > 0) && (string[cnt] != '\n'))
477 		cnt--;
478 
479 	  /* if we moved and found a newline go forward one to point at the
480 	   * actual start of the line....
481 	   */
482 	if ((cnt != offset) && (string[cnt] == '\n'))
483 		cnt++;
484 
485 	return cnt;
486 }
487 
488 /*
489  * Find the end of the current word in the string str, starting at
490  * offset - the end includes any trailing whitespace.  If the end of
491  * the string is found before a new word then just return the offset
492  * to the end of the string.
493  */
494 static int
495 find_eow(char *str, unsigned int offset)
496 {
497 	int start;
498 
499 	start = offset;
500 	  /* first skip any non-whitespace */
501 	while ((str[start] != '\0') && !isblank(str[start]))
502 		start++;
503 
504 	  /* see if we hit the end of the string */
505 	if (str[start] == '\0')
506 		return start;
507 
508 	  /* otherwise skip the whitespace.... */
509 	while ((str[start] != '\0') && isblank(str[start]))
510 		start++;
511 
512 	return start;
513 }
514 
515 /*
516  * Find the beginning of the current word in the string str, starting
517  * at offset.
518  */
519 static int
520 find_sow(char *str, unsigned int offset)
521 {
522 	int start;
523 
524 	start = offset;
525 
526 	if (start > 0) {
527 		if (isblank(str[start]) || isblank(str[start - 1])) {
528 			if (isblank(str[start - 1]))
529 				start--;
530 			  /* skip the whitespace.... */
531 			while ((start >= 0) && isblank(str[start]))
532 				start--;
533 		}
534 	}
535 
536 	  /* see if we hit the start of the string */
537 	if (start < 0)
538 		return 0;
539 
540 	  /* now skip any non-whitespace */
541 	while ((start >= 0) && !isblank(str[start]))
542 		start--;
543 
544 	if (start > 0)
545 		start++; /* last loop has us pointing at a space, adjust */
546 
547 	if (start < 0)
548 		start = 0;
549 
550 	return start;
551 }
552 
553 /*
554  * Scroll the field forward the given number of lines.
555  */
556 static void
557 _formi_scroll_fwd(FIELD *field, unsigned int amt)
558 {
559 	  /* check if we have lines to scroll */
560 	if (field->row_count < (field->start_line + field->rows))
561 		return;
562 
563 	field->start_line += min(amt,
564 				 field->row_count - field->start_line
565 				 - field->rows);
566 }
567 
568 /*
569  * Scroll the field backward the given number of lines.
570  */
571 static void
572 _formi_scroll_back(FIELD *field, unsigned int amt)
573 {
574 	if (field->start_line == 0)
575 		return;
576 
577 	field->start_line -= min(field->start_line, amt);
578 }
579 
580 /*
581  * Scroll the field forward the given number of characters.
582  */
583 void
584 _formi_hscroll_fwd(FIELD *field, int unsigned amt)
585 {
586 	int end, scroll_amt;
587 
588 	end = _formi_find_eol(field->buffers[0].string,
589 		       field->start_char + field->hscroll
590 		       + field->cursor_xpos) - field->start_char
591 		- field->hscroll - field->cursor_xpos;
592 
593 	scroll_amt = min(amt, end);
594 	if (scroll_amt < 0)
595 		scroll_amt = 0;
596 
597 	field->hscroll += scroll_amt;
598 	if (amt > field->cursor_xpos)
599 		field->cursor_xpos = 0;
600 	else
601 		field->cursor_xpos -= scroll_amt;
602 }
603 
604 /*
605  * Scroll the field backward the given number of characters.
606  */
607 void
608 _formi_hscroll_back(FIELD *field, unsigned int amt)
609 {
610 	int flen, sa;
611 
612 	sa = min(field->hscroll, amt);
613 	field->hscroll -= sa;
614 	field->cursor_xpos += sa;
615 	flen = field->cols;
616 	if (field->start_char > 0)
617 		flen--;
618 	if (field->cursor_xpos > flen)
619 		field->cursor_xpos = flen;
620 }
621 
622 /*
623  * Find the different pages in the form fields and assign the form
624  * page_starts array with the information to find them.
625  */
626 int
627 _formi_find_pages(FORM *form)
628 {
629 	int i, cur_page = 0;
630 
631 	if ((form->page_starts = (_FORMI_PAGE_START *)
632 	     malloc((form->max_page + 1) * sizeof(_FORMI_PAGE_START))) == NULL)
633 		return E_SYSTEM_ERROR;
634 
635 	  /* initialise the page starts array */
636 	memset(form->page_starts, 0,
637 	       (form->max_page + 1) * sizeof(_FORMI_PAGE_START));
638 
639 	for (i =0; i < form->field_count; i++) {
640 		if (form->fields[i]->page_break == 1)
641 			cur_page++;
642 		if (form->page_starts[cur_page].in_use == 0) {
643 			form->page_starts[cur_page].in_use = 1;
644 			form->page_starts[cur_page].first = i;
645 			form->page_starts[cur_page].last = i;
646 			form->page_starts[cur_page].top_left = i;
647 			form->page_starts[cur_page].bottom_right = i;
648 		} else {
649 			form->page_starts[cur_page].last = i;
650 			form->page_starts[cur_page].top_left =
651 				_formi_top_left(form,
652 						form->page_starts[cur_page].top_left,
653 						i);
654 			form->page_starts[cur_page].bottom_right =
655 				_formi_bottom_right(form,
656 						    form->page_starts[cur_page].bottom_right,
657 						    i);
658 		}
659 	}
660 
661 	return E_OK;
662 }
663 
664 /*
665  * Completely redraw the field of the given form.
666  */
667 void
668 _formi_redraw_field(FORM *form, int field)
669 {
670 	unsigned int pre, post, flen, slen, i, row, start, end, offset;
671 	char *str;
672 	FIELD *cur;
673 #ifdef DEBUG
674 	char buffer[100];
675 #endif
676 
677 	cur = form->fields[field];
678 	str = cur->buffers[0].string;
679 	flen = cur->cols;
680 	slen = 0;
681 	start = 0;
682 	end = 0;
683 
684 	wmove(form->subwin, (int) cur->form_row, (int) cur->form_col);
685 	for (row = 1; row <= cur->row_count; row++) {
686 		if (str == NULL) {
687 			start = end = 0;
688 		} else {
689 			if ((str[end] == '\0') || (str[end + 1] == '\0')
690 			    || (row == 1))
691 				start = end;
692 			else
693 				start = end + 1;
694 		}
695 
696 		if (cur->buffers[0].length > 0) {
697 			end = _formi_find_eol(str, start);
698 			slen = end - start + 1;
699 		} else
700 			slen = 0;
701 
702 		switch (cur->justification) {
703 		case JUSTIFY_RIGHT:
704 			post = 0;
705 			if (flen < slen)
706 				pre = 0;
707 			else
708 				pre = flen - slen;
709 
710 			break;
711 
712 		case JUSTIFY_CENTER:
713 			if (flen < slen) {
714 				pre = 0;
715 				post = 0;
716 			} else {
717 				pre = flen - slen;
718 				post = pre = pre / 2;
719 				  /* get padding right if centring is not even */
720 				if ((post + pre + slen) < flen)
721 					post++;
722 			}
723 			break;
724 
725 		case NO_JUSTIFICATION:
726 		case JUSTIFY_LEFT:
727 		default:
728 			pre = 0;
729 			if (flen <= slen)
730 				post = 0;
731 			else {
732 				post = flen - slen;
733 				if (post > flen)
734 					post = flen;
735 			}
736 			break;
737 		}
738 
739 		if (pre > cur->hscroll - start)
740 			pre = pre - cur->hscroll + start;
741 		else
742 			pre = 0;
743 
744 		if (slen > cur->hscroll) {
745 			slen -= cur->hscroll;
746 			post += cur->hscroll;
747 			if (post > flen)
748 				post = flen;
749 		} else {
750 			slen = 0;
751 			post = flen - pre;
752 		}
753 
754 		if (form->cur_field == field)
755 			wattrset(form->subwin, cur->fore);
756 		else
757 			wattrset(form->subwin, cur->back);
758 
759 #ifdef DEBUG
760 		if (_formi_create_dbg_file() == E_OK) {
761 			fprintf(dbg,
762      "redraw_field: start=%d, pre=%d, slen=%d, flen=%d, post=%d, hscroll=%d\n",
763 				start, pre, slen, flen, post, cur->hscroll);
764 			if (str != NULL) {
765 				strncpy(buffer, &str[cur->start_char], flen);
766 			} else {
767 				strcpy(buffer, "(null)");
768 			}
769 			buffer[flen] = '\0';
770 			fprintf(dbg, "redraw_field: %s\n", buffer);
771 		}
772 #endif
773 
774 		for (i = start + cur->hscroll; i < pre; i++)
775 			waddch(form->subwin, cur->pad);
776 
777 		offset = cur->hscroll;
778 		if (cur->start_char > 0)
779 			offset += cur->start_char - 1;
780 
781 		if (flen > cur->hscroll + 1) {
782 			if (flen > slen)
783 				flen -= cur->hscroll + 1;
784 		} else
785 			flen = 0;
786 
787 #ifdef DEBUG
788 		fprintf(dbg, "redraw_field: will add %d chars, offset is %d\n",
789 			min(slen, flen), offset);
790 #endif
791 		for (i = 0;
792 		     i < min(slen, flen); i++)
793 		{
794 #ifdef DEBUG
795 			fprintf(dbg, "adding char str[%d]=%c\n",
796 				i + offset, str[i + offset]);
797 #endif
798 			waddch(form->subwin,
799 			       ((cur->opts & O_PUBLIC) == O_PUBLIC)?
800 			       str[i + offset] : cur->pad);
801 		}
802 
803 		for (i = 0; i < post; i++)
804 			waddch(form->subwin, cur->pad);
805 	}
806 
807 	return;
808 }
809 
810 /*
811  * Display the fields attached to the form that are on the current page
812  * on the screen.
813  *
814  */
815 int
816 _formi_draw_page(FORM *form)
817 {
818 	int i;
819 
820 	if (form->page_starts[form->page].in_use == 0)
821 		return E_BAD_ARGUMENT;
822 
823 	wclear(form->subwin);
824 
825 	for (i = form->page_starts[form->page].first;
826 	     i <= form->page_starts[form->page].last; i++)
827 		_formi_redraw_field(form, i);
828 
829 	return E_OK;
830 }
831 
832 /*
833  * Add the character c at the position pos in buffer 0 of the given field
834  */
835 int
836 _formi_add_char(FIELD *field, unsigned int pos, char c)
837 {
838 	char *new;
839 	unsigned int new_size;
840 	int status;
841 
842 	  /*
843 	   * If buffer has not had a string before, set it to a blank
844 	   * string.  Everything should flow from there....
845 	   */
846 	if (field->buffers[0].string == NULL) {
847 		set_field_buffer(field, 0, "");
848 	}
849 
850 	if (_formi_validate_char(field, c) != E_OK) {
851 #ifdef DEBUG
852 		fprintf(dbg, "add_char: char %c failed char validation\n", c);
853 #endif
854 		return E_INVALID_FIELD;
855 	}
856 
857 #ifdef DEBUG
858 	fprintf(dbg, "add_char: pos=%d, char=%c\n", pos, c);
859 	fprintf(dbg,
860 	   "add_char enter: xpos=%d, start=%d, length=%d(%d), allocated=%d\n",
861 		field->cursor_xpos, field->start_char,
862 		field->buffers[0].length, strlen(field->buffers[0].string),
863 		field->buffers[0].allocated);
864 	fprintf(dbg, "add_char enter: %s\n", field->buffers[0].string);
865 	fprintf(dbg, "add_char enter: buf0_status=%d\n", field->buf0_status);
866 #endif
867 	if (((field->opts & O_BLANK) == O_BLANK) &&
868 	    (field->buf0_status == FALSE)) {
869 		field->buffers[0].length = 0;
870 		field->buffers[0].string[0] = '\0';
871 		pos = 0;
872 		field->start_char = 0;
873 		field->start_line = 0;
874 		field->hscroll = 0;
875 		field->row_count = 1;
876 		field->cursor_xpos = 0;
877 		field->cursor_ypos = 0;
878 	}
879 
880 
881 	if ((field->overlay == 0)
882 	    || ((field->overlay == 1) && (pos >= field->buffers[0].length))) {
883 		  /* first check if the field can have more chars...*/
884 		if ((((field->opts & O_STATIC) == O_STATIC) &&
885 		     (field->buffers[0].length >= field->cols)) ||
886 		    (((field->opts & O_STATIC) != O_STATIC) &&
887 		     ((field->max > 0) &&
888 		      (field->buffers[0].length >= field->max))))
889 			return E_REQUEST_DENIED;
890 
891 		if (field->buffers[0].length + 1
892 		    >= field->buffers[0].allocated) {
893 			new_size = field->buffers[0].allocated + 64
894 				- (field->buffers[0].allocated % 64);
895 			if ((new = (char *) realloc(field->buffers[0].string,
896 						    new_size )) == NULL)
897 				return E_SYSTEM_ERROR;
898 			field->buffers[0].allocated = new_size;
899 			field->buffers[0].string = new;
900 		}
901 	}
902 
903 	if ((field->overlay == 0) && (field->buffers[0].length > pos)) {
904 		bcopy(&field->buffers[0].string[pos],
905 		      &field->buffers[0].string[pos + 1],
906 		      field->buffers[0].length - pos + 1);
907 	}
908 
909 	field->buffers[0].string[pos] = c;
910 	if (pos >= field->buffers[0].length) {
911 		  /* make sure the string is terminated if we are at the
912 		   * end of the string, the terminator would be missing
913 		   * if we are are at the end of the field.
914 		   */
915 		field->buffers[0].string[pos + 1] = '\0';
916 	}
917 
918 	  /* only increment the length if we are inserting characters
919 	   * OR if we are at the end of the field in overlay mode.
920 	   */
921 	if ((field->overlay == 0)
922 	    || ((field->overlay == 1) && (pos >= field->buffers[0].length)))
923 			field->buffers[0].length++;
924 
925 	  /* wrap the field, if needed */
926 	status = _formi_wrap_field(field, pos);
927 	if (status != E_OK) {
928 		  /* wrap failed for some reason, back out the char insert */
929 		bcopy(&field->buffers[0].string[pos + 1],
930 		      &field->buffers[0].string[pos],
931 		      field->buffers[0].length - pos);
932 		field->buffers[0].length--;
933 	} else {
934 		field->buf0_status = TRUE;
935 		field->cursor_xpos++;
936 		if (field->cursor_xpos > field->cols - 1) {
937 			field->start_char++;
938 			field->cursor_xpos = field->cols - 1;
939 		}
940 	}
941 
942 #ifdef DEBUG
943 	fprintf(dbg,
944 	    "add_char exit: xpos=%d, start=%d, length=%d(%d), allocated=%d\n",
945 		field->cursor_xpos, field->start_char,
946 		field->buffers[0].length, strlen(field->buffers[0].string),
947 		field->buffers[0].allocated);
948 	fprintf(dbg,"add_char exit: %s\n", field->buffers[0].string);
949 	fprintf(dbg, "add_char exit: buf0_status=%d\n", field->buf0_status);
950 	fprintf(dbg, "add_char exit: status = %s\n",
951 		(status == E_OK)? "OK" : "FAILED");
952 #endif
953 	return status;
954 }
955 
956 /*
957  * Manipulate the text in a field, this takes the given form and performs
958  * the passed driver command on the current text field.  Returns 1 if the
959  * text field was modified.
960  */
961 int
962 _formi_manipulate_field(FORM *form, int c)
963 {
964 	FIELD *cur;
965 	char *str;
966 	unsigned int i, start, end, pos;
967 
968 	cur = form->fields[form->cur_field];
969 
970 #ifdef DEBUG
971 	fprintf(dbg,
972 		"entry: xpos=%d, start_char=%d, length=%d, allocated=%d\n",
973 		cur->cursor_xpos, cur->start_char, cur->buffers[0].length,
974 		cur->buffers[0].allocated);
975 	fprintf(dbg, "entry: string=");
976 	if (cur->buffers[0].string == NULL)
977 		fprintf(dbg, "(null)\n");
978 	else
979 		fprintf(dbg, "\"%s\"\n", cur->buffers[0].string);
980 #endif
981 
982 	  /* Cannot manipulate a null string! */
983 	if (cur->buffers[0].string == NULL)
984 		return E_REQUEST_DENIED;
985 
986 	switch (c) {
987 	case REQ_NEXT_CHAR:
988 		if ((cur->cursor_xpos + cur->start_char
989 		     - ((cur->start_char > 0)? 1 : 0) + cur->hscroll + 1)
990 		    > cur->buffers[0].length) {
991 			return E_REQUEST_DENIED;
992 		}
993 		cur->cursor_xpos++;
994 		if (cur->cursor_xpos >= cur->cols - cur->hscroll - 1) {
995 			if (cur->cols < (cur->hscroll  + 1))
996 				cur->cursor_xpos = 0;
997 			else
998 				cur->cursor_xpos = cur->cols
999 					- cur->hscroll - 1;
1000 			cur->start_char++;
1001 		}
1002 		break;
1003 
1004 	case REQ_PREV_CHAR:
1005 		if (cur->cursor_xpos == 0) {
1006 			if (cur->start_char > 0)
1007 				cur->start_char--;
1008 			else if (cur->hscroll > 0)
1009 				cur->hscroll--;
1010 			else
1011 				return E_REQUEST_DENIED;
1012 		} else
1013 			cur->cursor_xpos--;
1014 		break;
1015 
1016 	case REQ_NEXT_LINE:
1017 		cur->cursor_ypos++;
1018 		if (cur->cursor_ypos > cur->rows) {
1019 			if ((cur->opts & O_STATIC) == O_STATIC) {
1020 				if (cur->start_line + cur->cursor_ypos
1021 				    > cur->drows) {
1022 					cur->cursor_ypos--;
1023 					return E_REQUEST_DENIED;
1024 				}
1025 			} else {
1026 				if (cur->start_line + cur->cursor_ypos
1027 				    > cur->nrows + cur->rows) {
1028 					cur->cursor_ypos--;
1029 					return E_REQUEST_DENIED;
1030 				}
1031 			}
1032 			cur->start_line++;
1033 		}
1034 		break;
1035 
1036 	case REQ_PREV_LINE:
1037 		if (cur->cursor_ypos == 0) {
1038 			if (cur->start_line == 0)
1039 				return E_REQUEST_DENIED;
1040 			cur->start_line--;
1041 		} else
1042 			cur->cursor_ypos--;
1043 		break;
1044 
1045 	case REQ_NEXT_WORD:
1046 		start = cur->start_char + cur->cursor_xpos;
1047 		str = cur->buffers[0].string;
1048 
1049 		start = find_eow(str, start);
1050 
1051 		  /* check if we hit the end */
1052 		if (str[start] == '\0')
1053 			return E_REQUEST_DENIED;
1054 
1055 		  /* otherwise we must have found the start of a word...*/
1056 		if (start - cur->start_char < cur->cols) {
1057 			cur->cursor_xpos = start;
1058 		} else {
1059 			cur->start_char = start;
1060 			cur->cursor_xpos = 0;
1061 		}
1062 		break;
1063 
1064 	case REQ_PREV_WORD:
1065 		start = cur->start_char + cur->cursor_xpos;
1066 		if (cur->start_char > 0)
1067 			start--;
1068 
1069 		if (start == 0)
1070 			return E_REQUEST_DENIED;
1071 
1072 		str = cur->buffers[0].string;
1073 
1074 		start = find_sow(str, start);
1075 
1076 		if (start - cur->start_char > 0) {
1077 			cur->cursor_xpos = start;
1078 		} else {
1079 			cur->start_char = start;
1080 			cur->cursor_xpos = 0;
1081 		}
1082 		break;
1083 
1084 	case REQ_BEG_FIELD:
1085 		cur->start_char = 0;
1086 		cur->start_line = 0;
1087 		cur->cursor_xpos = 0;
1088 		cur->cursor_ypos = 0;
1089 		break;
1090 
1091 	case REQ_END_FIELD:
1092 		if (cur->row_count > cur->rows) {
1093 			cur->start_line = cur->row_count - cur->rows;
1094 			cur->cursor_ypos = cur->rows - 1;
1095 		} else {
1096 			cur->start_line = 0;
1097 			cur->cursor_ypos = cur->row_count - 1;
1098 		}
1099 
1100 		if ((str = rindex(cur->buffers[0].string, '\n')) == NULL) {
1101 			cur->cursor_xpos = cur->cols - 1;
1102 			if (cur->start_char < (cur->buffers[0].length +
1103 					       cur->cols)) {
1104 				cur->start_char = 0;
1105 				cur->cursor_xpos = cur->buffers[0].length;
1106 			} else {
1107 				cur->start_char = cur->buffers[0].length -
1108 					cur->cols;
1109 			}
1110 		} else {
1111 			cur->start_char = (str - cur->buffers[0].string);
1112 			if (strlen(str) > cur->cols)
1113 				cur->cursor_xpos = cur->cols;
1114 			else
1115 				cur->cursor_xpos = strlen(str);
1116 		}
1117 		break;
1118 
1119 	case REQ_BEG_LINE:
1120 		start = cur->start_char + cur->cursor_xpos;
1121 		if (cur->buffers[0].string[start] == '\n') {
1122 			if (start > 0)
1123 				start--;
1124 			else
1125 				return E_REQUEST_DENIED;
1126 		}
1127 
1128 		while ((start > 0)
1129 		       && (cur->buffers[0].string[start] != '\n'))
1130 			start--;
1131 
1132 		if (start > 0)
1133 			start++;
1134 
1135 		cur->start_char = start;
1136 		cur->cursor_xpos = 0;
1137 		break;
1138 
1139 	case REQ_END_LINE:
1140 		start = cur->start_char + cur->cursor_xpos;
1141 		end = _formi_find_eol(cur->buffers[0].string, start);
1142 		start = _formi_find_bol(cur->buffers[0].string, start);
1143 
1144 		if (end - start > cur->cols - 1) {
1145 			cur->cursor_xpos = cur->cols - 1;
1146 			cur->start_char = end - cur->cols + 3;
1147 		} else {
1148 			cur->cursor_xpos = end - start + 1;
1149 			cur->start_char = start;
1150 		}
1151 		break;
1152 
1153 	case REQ_LEFT_CHAR:
1154 		if ((cur->cursor_xpos == 0) && (cur->start_char == 0))
1155 			return E_REQUEST_DENIED;
1156 
1157 		if (cur->cursor_xpos == 0) {
1158 			cur->start_char--;
1159 			if (cur->buffers[0].string[cur->start_char] == '\n') {
1160 				if ((cur->cursor_ypos == 0) &&
1161 				    (cur->start_line == 0))
1162 				{
1163 					cur->start_char++;
1164 					return E_REQUEST_DENIED;
1165 				}
1166 
1167 				if (cur->cursor_ypos == 0)
1168 					cur->start_line--;
1169 				else
1170 					cur->cursor_ypos--;
1171 
1172 				end = _formi_find_eol(cur->buffers[0].string,
1173 					       cur->start_char);
1174 				start = _formi_find_bol(cur->buffers[0].string,
1175 						 cur->start_char);
1176 				if (end - start >= cur->cols) {
1177 					cur->cursor_xpos = cur->cols - 1;
1178 					cur->start_char = end - cur->cols;
1179 				} else {
1180 					cur->cursor_xpos = end - start;
1181 					cur->start_char = start;
1182 				}
1183 			}
1184 		} else
1185 			cur->cursor_xpos--;
1186 		break;
1187 
1188 	case REQ_RIGHT_CHAR:
1189 		pos = cur->start_char + cur->cursor_xpos;
1190 		if (cur->buffers[0].string[pos] == '\0')
1191 			return E_REQUEST_DENIED;
1192 
1193 #ifdef DEBUG
1194 		fprintf(dbg, "req_right_char enter: start=%d, xpos=%d, c=%c\n",
1195 			cur->start_char, cur->cursor_xpos,
1196 			cur->buffers[0].string[pos]);
1197 #endif
1198 
1199 		if (cur->buffers[0].string[pos] == '\n') {
1200 			start = pos + 1;
1201 			if (cur->buffers[0].string[start] == 0)
1202 				return E_REQUEST_DENIED;
1203 			end = _formi_find_eol(cur->buffers[0].string, start);
1204 			if (end - start > cur->cols) {
1205 				cur->cursor_xpos = cur->cols - 1;
1206 				cur->start_char = end - cur->cols - 1;
1207 			} else {
1208 				cur->cursor_xpos = end - start;
1209 				cur->start_char = start;
1210 			}
1211 		} else {
1212 			if (cur->cursor_xpos == cur->cols - 1)
1213 				cur->start_char++;
1214 			else
1215 				cur->cursor_xpos++;
1216 		}
1217 #ifdef DEBUG
1218 		fprintf(dbg, "req_right_char exit: start=%d, xpos=%d, c=%c\n",
1219 			cur->start_char, cur->cursor_xpos,
1220 			cur->buffers[0].string[cur->start_char +
1221 					      cur->cursor_xpos]);
1222 #endif
1223 		break;
1224 
1225 	case REQ_UP_CHAR:
1226 		if (cur->cursor_ypos == 0) {
1227 			if (cur->start_line == 0)
1228 				return E_REQUEST_DENIED;
1229 
1230 			cur->start_line--;
1231 		} else
1232 			cur->cursor_ypos--;
1233 
1234 		start = find_cur_line(cur);
1235 		end = _formi_find_eol(cur->buffers[0].string, start);
1236 		cur->start_char = start;
1237 		if (cur->cursor_xpos > end - start)
1238 			cur->cursor_xpos = end - start;
1239 		break;
1240 
1241 	case REQ_DOWN_CHAR:
1242 		if (cur->cursor_ypos == cur->rows - 1) {
1243 			if (cur->start_line + cur->rows == cur->row_count)
1244 				return E_REQUEST_DENIED;
1245 			cur->start_line++;
1246 		} else
1247 			cur->cursor_ypos++;
1248 
1249 		start = find_cur_line(cur);
1250 		end = _formi_find_eol(cur->buffers[0].string, start);
1251 		cur->start_char = start;
1252 		if (cur->cursor_xpos > end - start)
1253 			cur->cursor_xpos = end - start;
1254 		break;
1255 
1256 	case REQ_NEW_LINE:
1257 		if (_formi_add_char(cur, cur->start_char + cur->cursor_xpos,
1258 				    '\n') == E_OK)
1259 			cur->row_count++;
1260 		break;
1261 
1262 	case REQ_INS_CHAR:
1263 		_formi_add_char(cur, cur->start_char + cur->cursor_xpos,
1264 				cur->pad);
1265 		break;
1266 
1267 	case REQ_INS_LINE:
1268 		start = _formi_find_bol(cur->buffers[0].string, cur->start_char);
1269 		if (_formi_add_char(cur, start, '\n') == E_OK)
1270 			cur->row_count++;
1271 		break;
1272 
1273 	case REQ_DEL_CHAR:
1274 		if (cur->buffers[0].string[cur->start_char + cur->cursor_xpos]
1275 		    == '\0')
1276 			return E_REQUEST_DENIED;
1277 
1278 		start = cur->start_char + cur->cursor_xpos;
1279 		end = cur->buffers[0].length;
1280 		if (cur->buffers[0].string[start] == '\n') {
1281 			if (cur->row_count > 1) {
1282 				cur->row_count--;
1283 				_formi_join_line(cur, cur->buffers[0].string,
1284 						 start, JOIN_NEXT);
1285 			} else
1286 				cur->buffers[0].string[start] = '\0';
1287 		} else {
1288 			bcopy(&cur->buffers[0].string[start + 1],
1289 			      &cur->buffers[0].string[start],
1290 			      (unsigned) end - start + 1);
1291 		}
1292 
1293 		cur->buffers[0].length--;
1294 		break;
1295 
1296 	case REQ_DEL_PREV:
1297 		if ((cur->cursor_xpos == 0) && (cur->start_char == 0))
1298 			   return E_REQUEST_DENIED;
1299 
1300 		start = cur->cursor_xpos + cur->start_char;
1301 		end = cur->buffers[0].length;
1302 
1303 		if (cur->buffers[0].string[cur->start_char + cur->cursor_xpos] == '\n') {
1304 			_formi_join_line(cur, cur->buffers[0].string,
1305 					 cur->start_char + cur->cursor_xpos,
1306 					 JOIN_PREV);
1307 			cur->row_count--;
1308 		} else {
1309 			bcopy(&cur->buffers[0].string[start],
1310 			      &cur->buffers[0].string[start - 1],
1311 			      (unsigned) end - start + 1);
1312 		}
1313 
1314 		cur->buffers[0].length--;
1315 		if ((cur->cursor_xpos == 0) && (cur->start_char > 0))
1316 			cur->start_char--;
1317 		else if ((cur->cursor_xpos == cur->cols - 1)
1318 			 && (cur->start_char > 0))
1319 			cur->start_char--;
1320 		else if (cur->cursor_xpos > 0)
1321 			cur->cursor_xpos--;
1322 
1323 		break;
1324 
1325 	case REQ_DEL_LINE:
1326 		start = cur->start_char + cur->cursor_xpos;
1327 		end = _formi_find_eol(cur->buffers[0].string, start);
1328 		start = _formi_find_bol(cur->buffers[0].string, start);
1329 		bcopy(&cur->buffers[0].string[end + 1],
1330 		      &cur->buffers[0].string[start],
1331 		      (unsigned) cur->buffers[0].length - end + 1);
1332 		if (cur->row_count > 1)
1333 			cur->row_count--;
1334 		break;
1335 
1336 	case REQ_DEL_WORD:
1337 		start = cur->start_char + cur->cursor_xpos;
1338 		end = find_eow(cur->buffers[0].string, start);
1339 		start = find_sow(cur->buffers[0].string, start);
1340 		bcopy(&cur->buffers[0].string[end + 1],
1341 		      &cur->buffers[0].string[start],
1342 		      (unsigned) cur->buffers[0].length - end + 1);
1343 		cur->buffers[0].length -= end - start;
1344 		break;
1345 
1346 	case REQ_CLR_EOL:
1347 		  /*XXXX this right or should we just toast the chars? */
1348 		start = cur->start_char + cur->cursor_xpos;
1349 		end = _formi_find_eol(cur->buffers[0].string, start);
1350 		for (i = start; i < end; i++)
1351 			cur->buffers[0].string[i] = cur->pad;
1352 		break;
1353 
1354 	case REQ_CLR_EOF:
1355 		for (i = cur->start_char + cur->cursor_xpos;
1356 		     i < cur->buffers[0].length; i++)
1357 			cur->buffers[0].string[i] = cur->pad;
1358 		break;
1359 
1360 	case REQ_CLR_FIELD:
1361 		for (i = 0; i < cur->buffers[0].length; i++)
1362 			cur->buffers[0].string[i] = cur->pad;
1363 		break;
1364 
1365 	case REQ_OVL_MODE:
1366 		cur->overlay = 1;
1367 		break;
1368 
1369 	case REQ_INS_MODE:
1370 		cur->overlay = 0;
1371 		break;
1372 
1373 	case REQ_SCR_FLINE:
1374 		_formi_scroll_fwd(cur, 1);
1375 		break;
1376 
1377 	case REQ_SCR_BLINE:
1378 		_formi_scroll_back(cur, 1);
1379 		break;
1380 
1381 	case REQ_SCR_FPAGE:
1382 		_formi_scroll_fwd(cur, cur->rows);
1383 		break;
1384 
1385 	case REQ_SCR_BPAGE:
1386 		_formi_scroll_back(cur, cur->rows);
1387 		break;
1388 
1389 	case REQ_SCR_FHPAGE:
1390 		_formi_scroll_fwd(cur, cur->rows / 2);
1391 		break;
1392 
1393 	case REQ_SCR_BHPAGE:
1394 		_formi_scroll_back(cur, cur->rows / 2);
1395 		break;
1396 
1397 	case REQ_SCR_FCHAR:
1398 		_formi_hscroll_fwd(cur, 1);
1399 		break;
1400 
1401 	case REQ_SCR_BCHAR:
1402 		_formi_hscroll_back(cur, 1);
1403 		break;
1404 
1405 	case REQ_SCR_HFLINE:
1406 		_formi_hscroll_fwd(cur, cur->cols);
1407 		break;
1408 
1409 	case REQ_SCR_HBLINE:
1410 		_formi_hscroll_back(cur, cur->cols);
1411 		break;
1412 
1413 	case REQ_SCR_HFHALF:
1414 		_formi_hscroll_fwd(cur, cur->cols / 2);
1415 		break;
1416 
1417 	case REQ_SCR_HBHALF:
1418 		_formi_hscroll_back(cur, cur->cols / 2);
1419 		break;
1420 
1421 	default:
1422 		return 0;
1423 	}
1424 
1425 #ifdef DEBUG
1426 	fprintf(dbg, "exit: xpos=%d, start_char=%d, length=%d, allocated=%d\n",
1427 		cur->cursor_xpos, cur->start_char, cur->buffers[0].length,
1428 		cur->buffers[0].allocated);
1429 	fprintf(dbg, "exit: string=\"%s\"\n", cur->buffers[0].string);
1430 #endif
1431 	return 1;
1432 }
1433 
1434 /*
1435  * Validate the give character by passing it to any type character
1436  * checking routines, if they exist.
1437  */
1438 int
1439 _formi_validate_char(FIELD *field, char c)
1440 {
1441 	int ret_val;
1442 
1443 	if (field->type == NULL)
1444 		return E_OK;
1445 
1446 	ret_val = E_INVALID_FIELD;
1447 	_formi_do_char_validation(field, field->type, c, &ret_val);
1448 
1449 	return ret_val;
1450 }
1451 
1452 
1453 /*
1454  * Perform the validation of the character, invoke all field_type validation
1455  * routines.  If the field is ok then update ret_val to E_OK otherwise
1456  * ret_val is not changed.
1457  */
1458 static void
1459 _formi_do_char_validation(FIELD *field, FIELDTYPE *type, char c, int *ret_val)
1460 {
1461 	if ((type->flags & _TYPE_IS_LINKED) == _TYPE_IS_LINKED) {
1462 		_formi_do_char_validation(field, type->link->next, c, ret_val);
1463 		_formi_do_char_validation(field, type->link->prev, c, ret_val);
1464 	} else {
1465 		if (type->char_check == NULL)
1466 			*ret_val = E_OK;
1467 		else {
1468 			if (type->char_check((int)(unsigned char) c,
1469 					     field->args) == TRUE)
1470 				*ret_val = E_OK;
1471 		}
1472 	}
1473 }
1474 
1475 /*
1476  * Validate the current field.  If the field validation returns success then
1477  * return E_OK otherwise return E_INVALID_FIELD.
1478  *
1479  */
1480 int
1481 _formi_validate_field(FORM *form)
1482 {
1483 	FIELD *cur;
1484 	char *bp;
1485 	int ret_val, count;
1486 
1487 
1488 	if ((form == NULL) || (form->fields == NULL) ||
1489 	    (form->fields[0] == NULL))
1490 		return E_INVALID_FIELD;
1491 
1492 	cur = form->fields[form->cur_field];
1493 
1494 	bp = cur->buffers[0].string;
1495 	count = _formi_skip_blanks(bp, 0);
1496 
1497 	  /* check if we have a null field, depending on the nullok flag
1498 	   * this may be acceptable or not....
1499 	   */
1500 	if (cur->buffers[0].string[count] == '\0') {
1501 		if ((cur->opts & O_NULLOK) == O_NULLOK)
1502 			return E_OK;
1503 		else
1504 			return E_INVALID_FIELD;
1505 	}
1506 
1507 	  /* check if an unmodified field is ok */
1508 	if (cur->buf0_status == 0) {
1509 		if ((cur->opts & O_PASSOK) == O_PASSOK)
1510 			return E_OK;
1511 		else
1512 			return E_INVALID_FIELD;
1513 	}
1514 
1515 	  /* if there is no type then just accept the field */
1516 	if (cur->type == NULL)
1517 		return E_OK;
1518 
1519 	ret_val = E_INVALID_FIELD;
1520 	_formi_do_validation(cur, cur->type, &ret_val);
1521 
1522 	return ret_val;
1523 }
1524 
1525 /*
1526  * Perform the validation of the field, invoke all field_type validation
1527  * routines.  If the field is ok then update ret_val to E_OK otherwise
1528  * ret_val is not changed.
1529  */
1530 static void
1531 _formi_do_validation(FIELD *field, FIELDTYPE *type, int *ret_val)
1532 {
1533 	if ((type->flags & _TYPE_IS_LINKED) == _TYPE_IS_LINKED) {
1534 		_formi_do_validation(field, type->link->next, ret_val);
1535 		_formi_do_validation(field, type->link->prev, ret_val);
1536 	} else {
1537 		if (type->field_check == NULL)
1538 			*ret_val = E_OK;
1539 		else {
1540 			if (type->field_check(field, field_buffer(field, 0))
1541 			    == TRUE)
1542 				*ret_val = E_OK;
1543 		}
1544 	}
1545 }
1546 
1547 /*
1548  * Select the next/previous choice for the field, the driver command
1549  * selecting the direction will be passed in c.  Return 1 if a choice
1550  * selection succeeded, 0 otherwise.
1551  */
1552 int
1553 _formi_field_choice(FORM *form, int c)
1554 {
1555 	FIELDTYPE *type;
1556 	FIELD *field;
1557 
1558 	if ((form == NULL) || (form->fields == NULL) ||
1559 	    (form->fields[0] == NULL) ||
1560 	    (form->fields[form->cur_field]->type == NULL))
1561 		return 0;
1562 
1563 	field = form->fields[form->cur_field];
1564 	type = field->type;
1565 
1566 	switch (c) {
1567 	case REQ_NEXT_CHOICE:
1568 		if (type->next_choice == NULL)
1569 			return 0;
1570 		else
1571 			return type->next_choice(field,
1572 						 field_buffer(field, 0));
1573 
1574 	case REQ_PREV_CHOICE:
1575 		if (type->prev_choice == NULL)
1576 			return 0;
1577 		else
1578 			return type->prev_choice(field,
1579 						 field_buffer(field, 0));
1580 
1581 	default: /* should never happen! */
1582 		return 0;
1583 	}
1584 }
1585 
1586 /*
1587  * Update the fields if they have changed.  The parameter old has the
1588  * previous current field as the current field may have been updated by
1589  * the driver.  Return 1 if the form page needs updating.
1590  *
1591  */
1592 int
1593 _formi_update_field(FORM *form, int old_field)
1594 {
1595 	int cur, i;
1596 
1597 	cur = form->cur_field;
1598 
1599 	if (old_field != cur) {
1600 		if (!((cur >= form->page_starts[form->page].first) &&
1601 		      (cur <= form->page_starts[form->page].last))) {
1602 			  /* not on same page any more */
1603 			for (i = 0; i < form->max_page; i++) {
1604 				if ((form->page_starts[i].in_use == 1) &&
1605 				    (form->page_starts[i].first <= cur) &&
1606 				    (form->page_starts[i].last >= cur)) {
1607 					form->page = i;
1608 					return 1;
1609 				}
1610 			}
1611 		}
1612 	}
1613 
1614 	_formi_redraw_field(form, old_field);
1615 	_formi_redraw_field(form, form->cur_field);
1616 	return 0;
1617 }
1618 
1619 /*
1620  * Compare function for the field sorting
1621  *
1622  */
1623 static int
1624 field_sort_compare(const void *one, const void *two)
1625 {
1626 	const FIELD *a, *b;
1627 	int tl;
1628 
1629 	  /* LINTED const castaway; we don't modify these! */
1630 	a = (const FIELD *) *((const FIELD **) one);
1631 	b = (const FIELD *) *((const FIELD **) two);
1632 
1633 	if (a == NULL)
1634 		return 1;
1635 
1636 	if (b == NULL)
1637 		return -1;
1638 
1639 	  /*
1640 	   * First check the page, we want the fields sorted by page.
1641 	   *
1642 	   */
1643 	if (a->page != b->page)
1644 		return ((a->page > b->page)? 1 : -1);
1645 
1646 	tl = _formi_top_left(a->parent, a->index, b->index);
1647 
1648 	  /*
1649 	   * sort fields left to right, top to bottom so the top left is
1650 	   * the less than value....
1651 	   */
1652 	return ((tl == a->index)? -1 : 1);
1653 }
1654 
1655 /*
1656  * Sort the fields in a form ready for driver traversal.
1657  */
1658 void
1659 _formi_sort_fields(FORM *form)
1660 {
1661 	FIELD **sort_area;
1662 	int i;
1663 
1664 	CIRCLEQ_INIT(&form->sorted_fields);
1665 
1666 	if ((sort_area = (FIELD **) malloc(sizeof(FIELD *) * form->field_count))
1667 	    == NULL)
1668 		return;
1669 
1670 	bcopy(form->fields, sort_area, sizeof(FIELD *) * form->field_count);
1671 	qsort(sort_area, (unsigned) form->field_count, sizeof(FIELD *),
1672 	      field_sort_compare);
1673 
1674 	for (i = 0; i < form->field_count; i++)
1675 		CIRCLEQ_INSERT_TAIL(&form->sorted_fields, sort_area[i], glue);
1676 
1677 	free(sort_area);
1678 }
1679 
1680 /*
1681  * Set the neighbours for all the fields in the given form.
1682  */
1683 void
1684 _formi_stitch_fields(FORM *form)
1685 {
1686 	int above_row, below_row, end_above, end_below, cur_row, real_end;
1687 	FIELD *cur, *above, *below;
1688 
1689 	  /*
1690 	   * check if the sorted fields circle queue is empty, just
1691 	   * return if it is.
1692 	   */
1693 	if (CIRCLEQ_EMPTY(&form->sorted_fields))
1694 		return;
1695 
1696 	  /* initially nothing is above..... */
1697 	above_row = -1;
1698 	end_above = TRUE;
1699 	above = NULL;
1700 
1701 	  /* set up the first field as the current... */
1702 	cur = CIRCLEQ_FIRST(&form->sorted_fields);
1703 	cur_row = cur->form_row;
1704 
1705 	  /* find the first field on the next row if any */
1706 	below = CIRCLEQ_NEXT(cur, glue);
1707 	below_row = -1;
1708 	end_below = TRUE;
1709 	real_end = TRUE;
1710 	while (below != (void *)&form->sorted_fields) {
1711 		if (below->form_row != cur_row) {
1712 			below_row = below->form_row;
1713 			end_below = FALSE;
1714 			real_end = FALSE;
1715 			break;
1716 		}
1717 		below = CIRCLEQ_NEXT(below, glue);
1718 	}
1719 
1720 	  /* walk the sorted fields, setting the neighbour pointers */
1721 	while (cur != (void *) &form->sorted_fields) {
1722 		if (cur == CIRCLEQ_FIRST(&form->sorted_fields))
1723 			cur->left = NULL;
1724 		else
1725 			cur->left = CIRCLEQ_PREV(cur, glue);
1726 
1727 		if (cur == CIRCLEQ_LAST(&form->sorted_fields))
1728 			cur->right = NULL;
1729 		else
1730 			cur->right = CIRCLEQ_NEXT(cur, glue);
1731 
1732 		if (end_above == TRUE)
1733 			cur->up = NULL;
1734 		else {
1735 			cur->up = above;
1736 			above = CIRCLEQ_NEXT(above, glue);
1737 			if (above_row != above->form_row) {
1738 				end_above = TRUE;
1739 				above_row = above->form_row;
1740 			}
1741 		}
1742 
1743 		if (end_below == TRUE)
1744 			cur->down = NULL;
1745 		else {
1746 			cur->down = below;
1747 			below = CIRCLEQ_NEXT(below, glue);
1748 			if (below == (void *) &form->sorted_fields) {
1749 				end_below = TRUE;
1750 				real_end = TRUE;
1751 			} else if (below_row != below->form_row) {
1752 				end_below = TRUE;
1753 				below_row = below->form_row;
1754 			}
1755 		}
1756 
1757 		cur = CIRCLEQ_NEXT(cur, glue);
1758 		if ((cur != (void *) &form->sorted_fields)
1759 		    && (cur_row != cur->form_row)) {
1760 			cur_row = cur->form_row;
1761 			if (end_above == FALSE) {
1762 				for (; above != CIRCLEQ_FIRST(&form->sorted_fields);
1763 				     above = CIRCLEQ_NEXT(above, glue)) {
1764 					if (above->form_row != above_row) {
1765 						above_row = above->form_row;
1766 						break;
1767 					}
1768 				}
1769 			} else if (above == NULL) {
1770 				above = CIRCLEQ_FIRST(&form->sorted_fields);
1771 				end_above = FALSE;
1772 				above_row = above->form_row;
1773 			} else
1774 				end_above = FALSE;
1775 
1776 			if (end_below == FALSE) {
1777 				while (below_row == below->form_row) {
1778 					below = CIRCLEQ_NEXT(below,
1779 							     glue);
1780 					if (below ==
1781 					    (void *)&form->sorted_fields) {
1782 						real_end = TRUE;
1783 						end_below = TRUE;
1784 						break;
1785 					}
1786 				}
1787 
1788 				if (below != (void *)&form->sorted_fields)
1789 					below_row = below->form_row;
1790 			} else if (real_end == FALSE)
1791 				end_below = FALSE;
1792 
1793 		}
1794 	}
1795 }
1796