summaryrefslogtreecommitdiff
blob: c1c39e6a1ac0fe9c8698c1a0175c55ca4cf631b2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
#include "ufed-curses.h"

#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <locale.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>

#include "ufed-curses-help.h"

/* internal members */
static int     descriptionleft = 0;
static sFlag** faytsave        = NULL;
static size_t  maxDescWidth    = 0;
static char*   lineBuf         = NULL;
static sFlag*  flags           = NULL;

/* internal prototypes */
static int  findFlagStart(sFlag* flag, int* index, sWrap** wrap, int* line, bool* isFirstWrap);
static void free_flags(void);
static char getFlagSpecialChar(sFlag* flag, int index);
static void printFlagInfo(char* buf, sFlag* flag, int index, bool printFlagName, bool printFlagState);
static void setFlagWrapDraw(sFlag* flag, int index, sWrap** wrap, size_t* pos, size_t* len, bool* isFirstWrap);


/* static functions */
static char *getline(FILE *fp)
{
	static size_t size = LINE_MAX;

	if (NULL == lineBuf) {
		lineBuf = malloc(size);
		if (NULL == lineBuf)
			ERROR_EXIT(-1, "Can not allocate %lu bytes for line buffer\n", sizeof(char) * size);
	}

	if(fgets(lineBuf, size, fp) == NULL)
		return NULL;
	else {

		/* See to configuration bytes if not read already */
		if (!configDone) {
			/* Byte 1: Whether read-only-mode is set or not */
			if ( '0' != lineBuf[0] )
				ro_mode = true;

			configDone = true;

			/* Remove the leading bytes transporting configuration values */
			char *oldLine = lineBuf;
			lineBuf = malloc(size);
			if (NULL == lineBuf)
				ERROR_EXIT(-1, "Can not allocate %lu bytes for line buffer\n", sizeof(char) * size);
			memcpy(lineBuf, oldLine + 1, size - 1);
			free(oldLine);
		} /* End of having to read configuration bytes */

		char *p = strchr(lineBuf, '\n');
		if(p != NULL) {
			*p = '\0';
			return lineBuf;
		}
	}
	for(;;) {
		char *newLine = realloc(lineBuf, size + size / 2);
		if(newLine == NULL)
			ERROR_EXIT(-1, "Can not reallocate %lu bytes for line buffer\n",
				(size_t)(sizeof(char) * size * 1.5));
		lineBuf = newLine;
		newLine = NULL;
		if(fgets(lineBuf + size, size / 2, fp) == NULL)
			return NULL;
		else {
			char *p = strchr(lineBuf + size, '\n');
			if(p != NULL) {
				*p = '\0';
				return lineBuf;
			}
		}
		size += size/2;
	}
	return NULL; // never reached.
}

static void read_flags(void)
{
	FILE*  input     = fdopen(3, "r");
	int    lineNum   = 0;
	char*  line      = NULL;
	int    ndescr    = 0;
	char   endChar   = 0;
	size_t fullWidth = 0;
	struct {
		int start, end;
	} name, desc, desc_alt, pkg, state;

	if(input == NULL)
		ERROR_EXIT(-1, "fdopen failed with error %d\n", errno);
	atexit(&free_flags);

	for(line = getline(input); line ; line = getline(input)) {
		name.start  = name.end  = -1;
		state.start = state.end = -1;

		if (sscanf(line, "%n%*s%n [%n%*[ +-]%n] %d",
				&name.start,  &name.end,
				&state.start, &state.end,
				&ndescr) != 1)
			ERROR_EXIT(-1, "Flag read failed on line %d:\n\"%s\"\n", lineNum + 1, line);

		// Check stats
		if ((state.end - state.start) != 2)
			ERROR_EXIT(-1, "Illegal flag stats on line %d:\n\"%s\"\n", lineNum + 1, line);

		// Create a new flag
		line[name.end]  = '\0';
		line[state.end] = '\0';
		sFlag* newFlag = addFlag(&flags, &line[name.start], lineNum, ndescr, &line[state.start]);

		/* The minimum width of the left side display is:
		 * Space + Selection + Space + name + Space + Mask brackets/Force plus.
		 * = 1 + 3 + 1 + strlen(name) + 1 + 2
		 * = strlen(name) + 8
		 */
		if( (name.end - name.start + 8) > minwidth)
			minwidth = name.end - name.start + 8;

		/* read description(s) and determine flag status */
		for (int i = 0; i < ndescr; ++i) {
			desc.start     = desc.end     = -1;
			desc_alt.start = desc_alt.end = -1;
			pkg.start      = pkg.end      = -1;
			state.start    = state.end    = -1;

			line = getline(input);
			if (!line) break;

			if ( (sscanf(line, "\t%n%*[^\t]%n\t%n%*[^\t]%n\t (%n%*[^)]%n) [%n%*[ +-]%n%c",
					&desc.start,  &desc.end,
					&desc_alt.start,  &desc_alt.end,
					&pkg.start,   &pkg.end,
					&state.start, &state.end,
					&endChar) != 1)
			  || (']' != endChar) )
				ERROR_EXIT(-1, "Description read failed on line %d\n\"%s\"\n", lineNum + 1, line);

			// Check stats
			if ((state.end - state.start) != 7)
				ERROR_EXIT(-1, "Illegal description stats on line %d:\n\"%s\"\n", lineNum + 1, line);

			// Add description line to flag:
			line[desc.end]     = '\0';
			line[desc_alt.end] = '\0';
			line[state.end]    = '\0';
			if ( (pkg.end - pkg.start) > 1) {
				line[pkg.end]   = '\0';
				fullWidth = addFlagDesc(newFlag, &line[pkg.start], &line[desc.start],
										&line[desc_alt.start], &line[state.start]);
			} else
				fullWidth = addFlagDesc(newFlag, NULL, &line[desc.start],
										&line[desc_alt.start], &line[state.start]);

			// Note new max length if this line is longest:
			if (fullWidth > maxDescWidth)
				maxDescWidth = fullWidth;

			// Advance lineNum
			++lineNum;
		} // loop through description lines

		// Update flag states and add data to the list stats
		genFlagStats(newFlag);
		addLineStats(newFlag, &listStats);
	} // loop while input given

	fclose(input);

	if(flags == NULL)
		ERROR_EXIT(-1, "Unable to start: %s\n", "No Input!");

	// Save the last line, it is needed in several places
	bottomline = lineNum;
}


static int drawflag(sFlag* flag, bool highlight)
{
	// Return early if there is nothing to display:
	if (!isFlagLegal(flag))
		return 0;

	// Basic values for the flag display
	int    idx       = 0;    // The description index to start with
	int    line      = flag->currline;
	int    usedY     = 0;    // Counts how many lines this flag really needs to display
	sWrap* wrapPart  = NULL; // Wrap part to begin with/draw
	bool   wrapFirst = true; // The first part, pkg or desc

	// Get the starting description/wrapped line of the flag
	usedY = findFlagStart(flag, &idx, &wrapPart, &line, &wrapFirst);

	// findFlagStart returns -1 if the flag is out of the screen
	if (0 > usedY)
		return 0;

	// Window values (aka shortcuts)
	WINDOW* wLst    = win(List);
	int     lHeight = wHeight(List);
	int     lWidth  = wWidth(List);

	// Set up needed buffers
	char   buf[lWidth + 1];       // Buffer for the line to print
	char   desc[maxDescWidth];    // Buffer to assemble the description accoring to e_order and e_desc
	char   special;               // force/mask/none character
	memset(buf,  0, sizeof(char) * (lWidth + 1));
	memset(desc, 0, sizeof(char) * maxDescWidth);

	// Description and wrapped lines state values
	bool   hasBlankLeft  = false;                 // Set to true once the left side is blanked
	bool   hasBlankRight = false;                 // Set to true once the right (state) side is blanked
	bool   hasHead       = false;                 // Set to true once the left side (flag name and states) are printed
	size_t length        = lWidth - minwidth - 8; // Characters to print
	bool   newDesc       = true;                  // Set to fals when wrapped parts advance
	size_t pos           = descriptionleft;       // position in desc to start printing on

	// Safety check: Put in blank line if idx ended up too large
	if (idx >= flag->ndesc) {
		// This can happen when filters reduce the list too much
		// so blank lines must be displayed
		memset(buf, ' ', lWidth - 1);
		buf[lWidth] = '\0';
		waddstr(wLst, buf);
	}

	// print descriptions according to filters
	while ( (idx < flag->ndesc) && (line < lHeight) ) {

		// Continue if any of the filters apply:
		if (newDesc && !isDescLegal(flag, idx)) {
			++idx;
			continue;
		}

		// If the flag name and state are drawn, following lines
		// need to start with spaces
		if (hasHead && !hasBlankLeft) {
			memset(buf, ' ', minwidth);
			hasBlankLeft = true;
		}

		// Prepare new description or blank on wrapped parts
		if (newDesc) {
			special = getFlagSpecialChar(flag, idx);

			// Wrapped and not wrapped lines are unified here
			// to simplify the usage of different ordering and
			// stripped descriptions versus original descriptions
			if (flag->desc[idx].pkg) {
				if (e_order == eOrder_left)
					sprintf(desc, "(%s) %s", flag->desc[idx].pkg, e_desc == eDesc_ori
							? flag->desc[idx].desc
							: flag->desc[idx].desc_alt);
				else
					sprintf(desc, "%s (%s)", e_desc == eDesc_ori
							? flag->desc[idx].desc
							: flag->desc[idx].desc_alt,
							  flag->desc[idx].pkg);
			} else
				sprintf(desc, "%s", flag->desc[idx].desc);
		} else if (!hasBlankRight) {
			memset(buf + minwidth, ' ', 10);
			hasBlankRight = true;
		}

		/* --- Preparations done --- */

		// 1: Print left side info
		if (!hasHead || newDesc)
			// Note: If both are false, the buffer is blanked already
			printFlagInfo(buf, flag, idx, !hasHead, newDesc);

		// At this point buf is guaranteed to be filled up to minwidth + 8

		// For normal descriptions, pos and length are already set, but
		// not so for wrapped lines, these must be set for each line:
		if (eWrap_wrap == e_wrap) {
			setFlagWrapDraw(flag, idx, &wrapPart, &pos, &length, &wrapFirst);
			wrapPart = wrapPart->next;
			if (newDesc && wrapPart)
				newDesc = false;
		}

		// The right side of buf can be added now:
		sprintf(buf + minwidth + (newDesc ? 8 : 10), "%-*.*s",
			(int)length, (int)length,
			strlen(desc) > pos ? &desc[pos] : "");
		// Note: Follow up lines of wrapped descriptions are indented by 2

		/* Set correct color set according to highlighting and status*/
		if(highlight)
			wattrset(wLst, COLOR_PAIR(3) | A_BOLD | A_REVERSE);
		else
			wattrset(wLst, COLOR_PAIR(3));

		// Put the line on the screen
		mvwaddstr(wLst, line, 0, buf);
		mvwaddch(wLst, line, minwidth,     ACS_VLINE); // Before state
		mvwaddch(wLst, line, minwidth + 4, ACS_VLINE); // Between state and scope
		mvwaddch(wLst, line, minwidth + 7, ACS_VLINE); // After scope

		// Add (default) selection if this is the header line
		if (!hasHead) {
			hasHead = true;
			if (flag->globalForced) {
				if(highlight)
					wattrset(wLst, COLOR_PAIR(5) | A_REVERSE);
				else
					wattrset(wLst, COLOR_PAIR(5) | A_BOLD);
				mvwaddch(wLst, line, 2, '+');
			} else if (flag->globalMasked) {
				if(highlight)
					wattrset(wLst, COLOR_PAIR(4) | A_REVERSE);
				else
					wattrset(wLst, COLOR_PAIR(4) | A_BOLD);
				mvwaddch(wLst, line, 2, '-');
			} else if (' ' == flag->stateConf)
				mvwaddch(wLst, line, 2, flag->stateDefault);
			else
				mvwaddch(wLst, line, 2, flag->stateConf);
		}

		// Add [D]efault column content
		if ('f' == special) {
			if(highlight)
				wattrset(wLst, COLOR_PAIR(5) | A_REVERSE);
			else
				wattrset(wLst, COLOR_PAIR(5) | A_BOLD);
			mvwaddch(wLst, line, minwidth + 1, special);
		} else if ('m' == special) {
			if(highlight)
				wattrset(wLst, COLOR_PAIR(4) | A_REVERSE);
			else
				wattrset(wLst, COLOR_PAIR(4) | A_BOLD);
			mvwaddch(wLst, line, minwidth + 1, special);
		} else {
			if (' ' == flag->desc[idx].stateDefault)
				mvwaddch(wLst, line, minwidth + 1, flag->stateDefault);
			else
				mvwaddch(wLst, line, minwidth + 1, flag->desc[idx].stateDefault);
		}

		// Advance counters and possibly description index
		++line;
		++usedY;
		if (NULL == wrapPart)
			++idx;
	} // end of looping flag descriptions

	if(highlight)
		wmove(win(List), max(flag->currline, 0), 2);
	wnoutrefresh(win(List));

	return usedY;
}

static int callback(sFlag** curr, int key)
{
	WINDOW* wInp = win(Input);
	WINDOW* wLst = win(List);
	size_t  fLen = 0;

	if ( fayt[0]
	  && (key != KEY_BACKSPACE)
	  && (key != KEY_DC)
	  && (key != 0177)
	  && ( (key == ' ') || (key != (unsigned char)key) || !isprint(key)) ) {
		fayt[0] = '\0';
		drawStatus(true);
		wrefresh(wInp);
	} else
		wmove(wInp, 0, strlen(fayt));

	// Reset possible side scrolling of the current flags description first
	if(descriptionleft && (key != KEY_LEFT) && (key != KEY_RIGHT) ) {
		descriptionleft = 0;
		drawflag(*curr, TRUE);
	}

	switch(key) {
		case KEY_DC:
		case 0177:
		case KEY_BACKSPACE:
			fLen = strlen(fayt);
			if(0 == fLen)
				break;
			fayt[--fLen] = '\0';
			drawflag(*curr, FALSE);
			*curr = faytsave[fLen];
			if (!scrollcurrent())
				drawflag(*curr, TRUE);
			wattrset(wInp, COLOR_PAIR(5) | A_BOLD);
			mvwaddstr(wInp, 0, 0, fayt);
			whline(wInp, ' ', 2);
			if(fLen == 0)
				wmove(wLst, (*curr)->currline, 2);
			wnoutrefresh(wLst);
			wrefresh(wInp);
			break;
		case '\n':
		case KEY_ENTER:
			if (ro_mode) {
				if (yesno("Exit? (Y/N) "))
					return 0;
			} else if (yesno("Save and exit? (Y/N) "))
				return 0;
			break;
		case '\033':
			if (ro_mode) {
				if (yesno("Exit? (Y/N) "))
					return 0;
			} else if (yesno("Cancel? (Y/N) "))
				return 1;
			break;
		case ' ':
			// Masked flags can be turned off, nothing else
			if ( (*curr)->globalMasked || (*curr)->globalForced ) {
				if (' ' != (*curr)->stateConf)
					(*curr)->stateConf = ' ';
			} else {
				switch ((*curr)->stateConf) {
					case '+':
						(*curr)->stateConf = '-';
						break;
					case '-':
						(*curr)->stateConf = ' ';
						break;
					default:
						(*curr)->stateConf = '+';
						break;
				}
			}
			if (*curr != flags) {
				drawflag(*curr, TRUE);
				wmove(wLst, (*curr)->currline, 2);
				wrefresh(wLst);
			} else
				drawFlags();
			break;
		case KEY_LEFT:
			if (eWrap_normal == e_wrap) {
				if(descriptionleft > 0)
					descriptionleft -= min(descriptionleft, (wWidth(List) - minwidth) * 2 / 3);
				drawflag(*curr, TRUE);
				wmove(wLst, (*curr)->currline, 2);
				wrefresh(wLst);
			}
			break;
		case KEY_RIGHT:
			if (eWrap_normal == e_wrap) {
				descriptionleft += (wWidth(List) - minwidth) * 2 / 3;
				drawflag(*curr, TRUE);
				wmove(wLst, (*curr)->currline, 2);
				wrefresh(wLst);
			}
			break;

		case KEY_F(5):
			if (eScope_local  == e_scope)
				e_scope = eScope_all;
			else
				++e_scope;

			if ( !isFlagLegal(*curr)
			  && !setNextItem(0, true)
			  && !setPrevItem(0, true) )
				resetDisplay(true);
			else
				draw(true);
			break;

		case KEY_F(6):
			if (eState_notinstalled == e_state)
				e_state = eState_all;
			else
				++e_state;


			if ( !isFlagLegal(*curr)
			  && !setNextItem(0, true)
			  && !setPrevItem(0, true) )
				resetDisplay(true);
			else
				draw(true);
			break;

		case KEY_F(7):
			if      (eMask_both   == e_mask)
				e_mask = eMask_unmasked;
			else
				++e_mask;

			if ( !isFlagLegal(*curr)
			  && !setNextItem(0, true)
			  && !setPrevItem(0, true) )
				resetDisplay(true);
			else
				draw(true);

			break;

		case KEY_F(9):
			if (eOrder_left == e_order)
				e_order = eOrder_right;
			else
				e_order = eOrder_left;

			draw(true);
			break;

		case KEY_F(10):
			if (eDesc_ori == e_desc)
				e_desc = eDesc_alt;
			else
				e_desc = eDesc_ori;

			draw(true);
			break;

		case KEY_F(11):
			if (eWrap_normal == e_wrap) {
				e_wrap = eWrap_wrap;
				descriptionleft = 0;
			} else
				e_wrap = eWrap_normal;
			draw(true);
			break;

#ifdef NCURSES_MOUSE_VERSION
		case KEY_MOUSE:
			// Masked flags can be turned off, nothing else
			if ( (*curr)->globalMasked || (*curr)->globalForced ) {
				if (' ' != (*curr)->stateConf)
					(*curr)->stateConf = ' ';
			} else {
				switch ((*curr)->stateConf) {
					case '+':
						(*curr)->stateConf = '-';
						break;
					case '-':
						(*curr)->stateConf = ' ';
						break;
					default:
						(*curr)->stateConf = '+';
						break;
				}
			}
			if (*curr != flags) {
				drawflag(*curr, TRUE);
				wmove(wLst, (*curr)->currline, 2);
				wrefresh(wLst);
			} else {
				drawFlags();
				wmove(wInp, 0, strlen(fayt));
			}
			break;
#endif
		case '?':
			help();
			break;
		default:
			if( (key == (unsigned char) key) && isprint(key)) {
				sFlag* flag = *curr;
				fLen = strlen(fayt);
				if(fLen && strncasecmp(flag->name, fayt, fLen))
					--fLen;
				fayt[fLen]     = (char) key;
				faytsave[fLen] = *curr;
				fayt[++fLen]   = '\0';

				wmove(wInp, 0, fLen);

				/* if the current flag already matches the input string,
				 * then update the input area only.
				 */
				if(!strncasecmp(flag->name, fayt, fLen)) {
					wattrset(wInp, COLOR_PAIR(5) | A_BOLD);
					mvwaddstr(wInp, 0, 0, fayt);
					wrefresh(wInp);
				}
				/* if the current flag does not match, search one that does. */
				else {
					do flag = flag->next;
					while( (flag != *curr)
					    && ( ( strncasecmp(flag->name, fayt, fLen)
					    	|| !isFlagLegal(flag)) ) );

					/* if there was no match (or the match is filtered),
					 * update the input area to show that there is no match
					 */
					if (flag == *curr) {
						wattrset(wInp, COLOR_PAIR(4) | A_BOLD | A_REVERSE);
						mvwaddstr(wInp, 0, 0, fayt);
						wmove(wInp, 0, fLen - 1);
						wrefresh(wInp);
					} else {
						drawflag(*curr, FALSE);
						*curr = flag;
						if (!scrollcurrent())
							drawflag(*curr, TRUE);
						wattrset(wInp, COLOR_PAIR(5) | A_BOLD);
						mvwaddstr(wInp, 0, 0, fayt);
						wmove(wInp, 0, fLen);
						wrefresh(wInp);
					}
				}
			}
			break;
	}

	return -1;
}

/** @brief find the first description/wrapped part drawn on line 0.
  *
  * Determine with which description to start.
  * Overly long description lists might not fit on one screen,
  * and therefore must be scrolled instead of the flags
  * themselves.
  * If descriptions are wrapped, any description must be held
  * until wrapPart is either NULL, or a part on the screen is
  * reached.
**/
static int findFlagStart(sFlag* flag, int* index, sWrap** wrap, int* line, bool* isFirstWrap)
{
	int    usedLines  = 0;
	int    flagHeight = getFlagHeight(flag); // Will recalculate wrap parts if needed
	sWrap* wrapPart = NULL;

	if (*line < 0) {

		// Only do anything if the flag can reach the screen:
		if (-(*line) >= flagHeight)
			return -1;

		// Now loop until the screen is entered (line == 0)
		while (*line < 0) {
			if (isDescLegal(flag, *index)) {
				if (eWrap_normal == e_wrap) {
					++(*line);
					++(*index);
					++usedLines;
				} else {
					/* With wrapped descriptions there are two possible
					 * situations:
					 * a) The list of wrapped lines is shorter than the
					 *    lines to be skipped to get this description on
					 *    the screen. In this case the full description
					 *    can be fast forwareded.
					 * b) The number of lines above the screen is less
					 *    than the number of wrapped parts. In this case
					 *    the first on screen part must be found.
					 */
					int wrapCount = flag->desc[*index].wrapCount;
					wrapPart      = flag->desc[*index].wrap;
					*isFirstWrap  = true;
					if (wrapPart && wrapCount && (-(*line) < wrapCount)) {
						// Situation b) This description enters screen
						while (wrapPart && (*line < 0)) {
							++(*line);
							++usedLines;
							wrapPart = wrapPart->next;
							if (wrapPart && !wrapPart->pos)
								*isFirstWrap = false;
							// Note: The wrap parts are already calculated
							//       to resemble the current order.
						}
					} else {
						// Situation a) Fast forward
						*line     += wrapCount;
						usedLines += wrapCount;
						++(*index);
					}
				} // End of handling wrapped lines
			} // End of having a legal flag
			else
				++(*index);
		} // end of moving to line 0

		// Write back wrapPart:
		*wrap = wrapPart;
	}

	return usedLines;
}

static void free_flags(void)
{
	sFlag* flag = flags->prev;

	// Clear all flags
	while (flags) {
		if (flag)
			destroyFlag(&flags, &flag);
		else
			destroyFlag(&flags, &flags);
		flag = flags ? flags->prev ? flags->prev : flags : NULL;
	}

	// Clear line buffer
	if (lineBuf)
		free(lineBuf);
}

static char getFlagSpecialChar(sFlag* flag, int index)
{
	// Return special character if needed:
	if (isDescForced(flag, index))
		return 'f';
	else if (isDescMasked(flag, index))
		return 'm';
	return ' ';
}


static void printFlagInfo(char* buf, sFlag* flag, int index, bool printFlagName, bool printFlagState)
{
	if (printFlagName)
		sprintf(buf, " %c%c%c %s%s%s%-*s ",
			/* State of selection */
			flag->stateConf == ' ' ? '(' : '[',
			' ', // Filled in later
			flag->stateConf == ' ' ? ')' : ']',
			/* name */
			flag->globalForced ? "(" : flag->globalMasked ? "(-" : "",
			flag->name,
			(flag->globalForced || flag->globalMasked) ? ")" : "",
			/* distance */
			(int)(minwidth
				- (flag->globalForced ? 3 : flag->globalMasked ? 2 : 5)
				- strlen(flag->name)), " ");

	if (printFlagState)
		/* Display flag state
		 * The order in which the states are to be displayed is:
		 * 1. [D]efaults (make.defaults, IUSE, package.mask, package.force)
		 *    Note: Filled in later
		 * 2. [P]rofile package.use files
		 * 3. [C]onfiguration (make.conf, users package.use)
		 * 4. global/local
		 * 5. installed/not installed
		 */
		sprintf(buf + minwidth, "  %c%c %c%c ",
			flag->desc[index].statePackage,
			' ' == flag->desc[index].statePkgUse ?
				flag->stateConf : flag->desc[index].statePkgUse,
			flag->desc[index].isGlobal ? ' ' : 'L',
			flag->desc[index].isInstalled ? 'i' : ' ');
}

static void setFlagWrapDraw(sFlag* flag, int index, sWrap** wrap, size_t* pos, size_t* len, bool* isFirstWrap)
{
	sWrap* wrapPart = *wrap;

	if (NULL == wrapPart) {
		wrapPart     = flag->desc[index].wrap;
		*isFirstWrap = true;
	} else if (*isFirstWrap
			&& (flag->desc[index].wrap != wrapPart)
			&& !wrapPart->pos)
		*isFirstWrap = false;

	// Position and length can be written back already
	*pos = wrapPart->pos;
	*len = wrapPart->len;

	// If this was switched, add the first length
	if ((false == *isFirstWrap) && (0 == *pos)) {
		// Add the length of either the package list or the
		// description (stripped or normal) or drawFlag will
		// end up reprinting from the beginning due to the
		// unified description string.
		if (eOrder_left == e_order)
			*pos += sizeof(flag->desc[index].pkg);
		else
			*pos += eDesc_ori == e_desc
				  ? sizeof(flag->desc[index].desc)
				  : sizeof(flag->desc[index].desc_alt);
	}

	// Write back wrap part pointer
	*wrap = wrapPart;
}


int main(void)
{
	int result = EXIT_SUCCESS;
	const char subtitle_ro[] = "USE flags can be browsed, but changes will NOT be saved!";
	const char subtitle_rw[] = "Select desired USE flags from the list below:";

	read_flags();
	fayt     = (char*)  calloc(minwidth, sizeof(*fayt));
	faytsave = (sFlag**)calloc(minwidth, sizeof(*faytsave));
	if(fayt==NULL || faytsave==NULL)
		ERROR_EXIT(-1, "Unable to allocate %lu bytes for search buffer.\n",
			(minwidth * sizeof(*fayt)) + (minwidth * sizeof(*faytsave)));
	fayt[0] = '\0';

	initcurses();

	/* Some notes on the keys:
	 * - The key '\0' (or simply 0) stops the processing of the
	 * array. This means, templates or future keys can be added
	 * beforehand behind a key=0 line - they will never be
	 * displayed.
	 * - key < 0 will show the key name only. This is useful for
	 * adding spaces or titles.
	 * - The texts are dynamic. As a smaller display shows only
	 * a limited amount of characters, texts should be crafted to
	 * start with their core information.
	 * Bad : "Show only global" => "Show only g" => "Show o"
	 * Good: "Global flags"     => "Global flag" => "Global"
	 */
	sKey keys[] = {
		/* Row 0 left - General keys */
		MAKE_KEY('?',    "?:",     "Help",   "",     "", NULL,           0),
		MAKE_KEY('\n',   "Enter:", "Save",   "Exit", "", (int*)&ro_mode, 0),
		MAKE_KEY('\033', "Esc:",   "Cancel", "Exit", "", (int*)&ro_mode, 0),

		/* Row 0 right - Display style (description) */
		MAKE_KEY(-1, "  ", "", "", "", NULL, 0),
		MAKE_KEY(KEY_F( 9), "F9:",  "Pkg right",  "Pkg left",    "", (int*)&e_order, 0),
		MAKE_KEY(KEY_F(10), "F10:", "Strip desc", "Full desc",   "", (int*)&e_desc,  0),
		MAKE_KEY(KEY_F(11), "F11:", "Wrap desc",  "Unwrap desc", "", (int*)&e_wrap,  0),

		/* Row 1 - Filter settings */
		MAKE_KEY(-1, "Filter: ", "", "", "", NULL, 1),
		MAKE_KEY(KEY_F( 5), "F5:", "Global only", "Local only",    "Both Scopes",   (int*)&e_scope, 1),
		MAKE_KEY(KEY_F( 6), "F6:", "Inst pkgs",   "Not inst pkgs", "All pkgs",      (int*)&e_state, 1),
		MAKE_KEY(KEY_F( 7), "F7:", "Masked only", "Both states",   "Unmasked only", (int*)&e_mask,  1),
		MAKE_KEY(0, "", "", "", "", NULL, 0), /* processing stops here (row _MUST_ be 0 here!) */

		/* future keys, that are planned */
		MAKE_KEY(KEY_F( 8), "F8:",  "Unknown flags", "Known flags", "all", NULL, 1)
	};

	result = maineventloop(ro_mode ? subtitle_ro : subtitle_rw,
				&callback, &drawflag, flags, keys, true);

	cursesdone();

	if(0 == result) {
		FILE *output = fdopen(4, "w");
		sFlag *flag = flags;
		do {
			switch(flag->stateConf)
			{
			case '+':
				fprintf(output, "%s\n", flag->name);
				break;
			case '-':
				fprintf(output, "-%s\n", flag->name);
				break;
			}
			flag = flag->next;
		} while(flag != flags);
		fclose(output);
	}

	if (fayt)     free(fayt);
	if (faytsave) free(faytsave);

	return result;
}