xref: /dragonfly/contrib/ncurses/ncurses/base/lib_addch.c (revision 0cadad7e49c6219b0de0675ef6a6f44683d177d4)
1 /****************************************************************************
2  * Copyright 2019,2020 Thomas E. Dickey                                     *
3  * Copyright 1998-2016,2017 Free Software Foundation, Inc.                  *
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29 
30 /*
31 **        lib_addch.c
32 **
33 **        The routine waddch().
34 **
35 */
36 
37 #include <curses.priv.h>
38 #include <ctype.h>
39 
40 MODULE_ID("$Id: lib_addch.c,v 1.134 2020/02/02 23:34:34 tom Exp $")
41 
42 static const NCURSES_CH_T blankchar = NewChar(BLANK_TEXT);
43 
44 /*
45  * Ugly microtweaking alert.  Everything from here to end of module is
46  * likely to be speed-critical -- profiling data sure says it is!
47  * Most of the important screen-painting functions are shells around
48  * waddch().  So we make every effort to reduce function-call overhead
49  * by inlining stuff, even at the cost of making wrapped copies for
50  * export.  Also we supply some internal versions that don't call the
51  * window sync hook, for use by string-put functions.
52  */
53 
54 /* Return bit mask for clearing color pair number if given ch has color */
55 #define COLOR_MASK(ch) (~(attr_t)(((ch) & A_COLOR) ? A_COLOR : 0))
56 
57 static NCURSES_INLINE NCURSES_CH_T
render_char(WINDOW * win,NCURSES_CH_T ch)58 render_char(WINDOW *win, NCURSES_CH_T ch)
59 /* compute a rendition of the given char correct for the current context */
60 {
61     attr_t a = WINDOW_ATTRS(win);
62     int pair = GetPair(ch);
63 
64     if (ISBLANK(ch)
65           && AttrOf(ch) == A_NORMAL
66           && pair == 0) {
67           /* color/pair in attrs has precedence over bkgrnd */
68           ch = win->_nc_bkgd;
69           SetAttr(ch, a | AttrOf(win->_nc_bkgd));
70           if ((pair = GET_WINDOW_PAIR(win)) == 0)
71               pair = GetPair(win->_nc_bkgd);
72           SetPair(ch, pair);
73     } else {
74           /* color in attrs has precedence over bkgrnd */
75           a |= AttrOf(win->_nc_bkgd) & COLOR_MASK(a);
76           /* color in ch has precedence */
77           if (pair == 0) {
78               if ((pair = GET_WINDOW_PAIR(win)) == 0)
79                     pair = GetPair(win->_nc_bkgd);
80           }
81           AddAttr(ch, (a & COLOR_MASK(AttrOf(ch))));
82           SetPair(ch, pair);
83     }
84 
85     TR(TRACE_VIRTPUT,
86        ("render_char bkg %s (%d), attrs %s (%d) -> ch %s (%d)",
87           _tracech_t2(1, CHREF(win->_nc_bkgd)),
88           GetPair(win->_nc_bkgd),
89           _traceattr(WINDOW_ATTRS(win)),
90           GET_WINDOW_PAIR(win),
91           _tracech_t2(3, CHREF(ch)),
92           GetPair(ch)));
93 
94     return (ch);
95 }
96 
97 NCURSES_EXPORT(NCURSES_CH_T)
_nc_render(WINDOW * win,NCURSES_CH_T ch)98 _nc_render(WINDOW *win, NCURSES_CH_T ch)
99 /* make render_char() visible while still allowing us to inline it below */
100 {
101     return render_char(win, ch);
102 }
103 
104 /* check if position is legal; if not, return error */
105 #ifndef NDEBUG                          /* treat this like an assertion */
106 #define CHECK_POSITION(win, x, y) \
107           if (y > win->_maxy \
108            || x > win->_maxx \
109            || y < 0 \
110            || x < 0) { \
111                     TR(TRACE_VIRTPUT, ("Alert! Win=%p _curx = %d, _cury = %d " \
112                                            "(_maxx = %d, _maxy = %d)", win, x, y, \
113                                            win->_maxx, win->_maxy)); \
114                     return(ERR); \
115           }
116 #else
117 #define CHECK_POSITION(win, x, y)       /* nothing */
118 #endif
119 
120 static bool
newline_forces_scroll(WINDOW * win,NCURSES_SIZE_T * ypos)121 newline_forces_scroll(WINDOW *win, NCURSES_SIZE_T *ypos)
122 {
123     bool result = FALSE;
124 
125     if (*ypos >= win->_regtop && *ypos <= win->_regbottom) {
126           if (*ypos == win->_regbottom) {
127               *ypos = win->_regbottom;
128               result = TRUE;
129           } else if (*ypos < win->_maxy) {
130               *ypos = (NCURSES_SIZE_T) (*ypos + 1);
131           }
132     } else if (*ypos < win->_maxy) {
133           *ypos = (NCURSES_SIZE_T) (*ypos + 1);
134     }
135     return result;
136 }
137 
138 /*
139  * The _WRAPPED flag is useful only for telling an application that we've just
140  * wrapped the cursor.  We don't do anything with this flag except set it when
141  * wrapping, and clear it whenever we move the cursor.  If we try to wrap at
142  * the lower-right corner of a window, we cannot move the cursor (since that
143  * wouldn't be legal).  So we return an error (which is what SVr4 does).
144  * Unlike SVr4, we can successfully add a character to the lower-right corner
145  * (Solaris 2.6 does this also, however).
146  */
147 static int
wrap_to_next_line(WINDOW * win)148 wrap_to_next_line(WINDOW *win)
149 {
150     win->_flags |= _WRAPPED;
151     if (newline_forces_scroll(win, &(win->_cury))) {
152           win->_curx = win->_maxx;
153           if (!win->_scroll)
154               return (ERR);
155           scroll(win);
156     }
157     win->_curx = 0;
158     return (OK);
159 }
160 
161 #if USE_WIDEC_SUPPORT
162 static int waddch_literal(WINDOW *, NCURSES_CH_T);
163 /*
164  * Fill the given number of cells with blanks using the current background
165  * rendition.  This saves/restores the current x-position.
166  */
167 static void
fill_cells(WINDOW * win,int count)168 fill_cells(WINDOW *win, int count)
169 {
170     NCURSES_CH_T blank = blankchar;
171     int save_x = win->_curx;
172     int save_y = win->_cury;
173 
174     while (count-- > 0) {
175           if (waddch_literal(win, blank) == ERR)
176               break;
177     }
178     win->_curx = (NCURSES_SIZE_T) save_x;
179     win->_cury = (NCURSES_SIZE_T) save_y;
180 }
181 #endif
182 
183 /*
184  * Build up the bytes for a multibyte character, returning the length when
185  * complete (a positive number), -1 for error and -2 for incomplete.
186  */
187 #if USE_WIDEC_SUPPORT
188 NCURSES_EXPORT(int)
_nc_build_wch(WINDOW * win,ARG_CH_T ch)189 _nc_build_wch(WINDOW *win, ARG_CH_T ch)
190 {
191     char *buffer = WINDOW_EXT(win, addch_work);
192     int len;
193     int x = win->_curx;
194     int y = win->_cury;
195     mbstate_t state;
196     wchar_t result;
197 
198     if ((WINDOW_EXT(win, addch_used) != 0) &&
199           (WINDOW_EXT(win, addch_x) != x ||
200            WINDOW_EXT(win, addch_y) != y)) {
201           /* discard the incomplete multibyte character */
202           WINDOW_EXT(win, addch_used) = 0;
203           TR(TRACE_VIRTPUT,
204              ("Alert discarded multibyte on move (%d,%d) -> (%d,%d)",
205               WINDOW_EXT(win, addch_y), WINDOW_EXT(win, addch_x),
206               y, x));
207     }
208     WINDOW_EXT(win, addch_x) = x;
209     WINDOW_EXT(win, addch_y) = y;
210 
211     init_mb(state);
212     buffer[WINDOW_EXT(win, addch_used)] = (char) CharOf(CHDEREF(ch));
213     WINDOW_EXT(win, addch_used) += 1;
214     buffer[WINDOW_EXT(win, addch_used)] = '\0';
215     if ((len = (int) mbrtowc(&result,
216                                    buffer,
217                                    (size_t) WINDOW_EXT(win, addch_used),
218                                    &state)) > 0) {
219           attr_t attrs = AttrOf(CHDEREF(ch));
220           if_EXT_COLORS(int pair = GetPair(CHDEREF(ch)));
221           SetChar(CHDEREF(ch), result, attrs);
222           if_EXT_COLORS(SetPair(CHDEREF(ch), pair));
223           WINDOW_EXT(win, addch_used) = 0;
224     } else if (len == -1) {
225           /*
226            * An error occurred.  We could either discard everything,
227            * or assume that the error was in the previous input.
228            * Try the latter.
229            */
230           TR(TRACE_VIRTPUT, ("Alert! mbrtowc returns error"));
231           /* handle this with unctrl() */
232           WINDOW_EXT(win, addch_used) = 0;
233     }
234     return len;
235 }
236 #endif /* USE_WIDEC_SUPPORT */
237 
238 static
239 #if !USE_WIDEC_SUPPORT                  /* cannot be inline if it is recursive */
240 NCURSES_INLINE
241 #endif
242 int
waddch_literal(WINDOW * win,NCURSES_CH_T ch)243 waddch_literal(WINDOW *win, NCURSES_CH_T ch)
244 {
245     int x;
246     int y;
247     struct ldat *line;
248 
249     x = win->_curx;
250     y = win->_cury;
251 
252     CHECK_POSITION(win, x, y);
253 
254     ch = render_char(win, ch);
255 
256     line = win->_line + y;
257 
258     CHANGED_CELL(line, x);
259 
260     /*
261      * Build up multibyte characters until we have a wide-character.
262      */
263 #if NCURSES_SP_FUNCS
264 #define DeriveSP() SCREEN *sp = _nc_screen_of(win);
265 #else
266 #define DeriveSP()            /*nothing */
267 #endif
268     if_WIDEC({
269           DeriveSP();
270           if (WINDOW_EXT(win, addch_used) != 0 || !Charable(ch)) {
271               int len = _nc_build_wch(win, CHREF(ch));
272 
273               if (len >= -1) {
274                     attr_t attr = AttrOf(ch);
275 
276                     /* handle EILSEQ (i.e., when len >= -1) */
277                     if (len == -1 && is8bits(CharOf(ch))) {
278                         const char *s = NCURSES_SP_NAME(unctrl)
279                           (NCURSES_SP_ARGx (chtype) CharOf(ch));
280 
281                         if (s[1] != '\0') {
282                               int rc = OK;
283                               while (*s != '\0') {
284                                   rc = waddch(win, UChar(*s) | attr);
285                                   if (rc != OK)
286                                         break;
287                                   ++s;
288                               }
289                               return rc;
290                         }
291                     }
292                     if (len == -1)
293                         return waddch(win, ' ' | attr);
294               } else {
295                     return OK;
296               }
297           }
298     });
299 
300     /*
301      * Non-spacing characters are added to the current cell.
302      *
303      * Spacing characters that are wider than one column require some display
304      * adjustments.
305      */
306     if_WIDEC({
307           int len = _nc_wacs_width(CharOf(ch));
308           int i;
309           int j;
310           wchar_t *chars;
311 
312           if (len == 0) {               /* non-spacing */
313               if ((x > 0 && y >= 0)
314                     || (win->_maxx >= 0 && win->_cury >= 1)) {
315                     if (x > 0 && y >= 0)
316                         chars = (win->_line[y].text[x - 1].chars);
317                     else
318                         chars = (win->_line[y - 1].text[win->_maxx].chars);
319                     for (i = 0; i < CCHARW_MAX; ++i) {
320                         if (chars[i] == 0) {
321                               TR(TRACE_VIRTPUT,
322                                  ("added non-spacing %d: %x",
323                                   x, (int) CharOf(ch)));
324                               chars[i] = CharOf(ch);
325                               break;
326                         }
327                     }
328               }
329               goto testwrapping;
330           } else if (len > 1) {         /* multi-column characters */
331               /*
332                * Check if the character will fit on the current line.  If it does
333                * not fit, fill in the remainder of the line with blanks.  and
334                * move to the next line.
335                */
336               if (len > win->_maxx + 1) {
337                     TR(TRACE_VIRTPUT, ("character will not fit"));
338                     return ERR;
339               } else if (x + len > win->_maxx + 1) {
340                     int count = win->_maxx + 1 - x;
341                     TR(TRACE_VIRTPUT, ("fill %d remaining cells", count));
342                     fill_cells(win, count);
343                     if (wrap_to_next_line(win) == ERR)
344                         return ERR;
345                     x = win->_curx;
346                     y = win->_cury;
347                     CHECK_POSITION(win, x, y);
348                     line = win->_line + y;
349               }
350               /*
351                * Check for cells which are orphaned by adding this character, set
352                * those to blanks.
353                *
354                * FIXME: this actually could fill j-i cells, more complicated to
355                * setup though.
356                */
357               for (i = 0; i < len; ++i) {
358                     if (isWidecBase(win->_line[y].text[x + i])) {
359                         break;
360                     } else if (isWidecExt(win->_line[y].text[x + i])) {
361                         for (j = i; x + j <= win->_maxx; ++j) {
362                               if (!isWidecExt(win->_line[y].text[x + j])) {
363                                   TR(TRACE_VIRTPUT, ("fill %d orphan cells", j));
364                                   fill_cells(win, j);
365                                   break;
366                               }
367                         }
368                         break;
369                     }
370               }
371               /*
372                * Finally, add the cells for this character.
373                */
374               for (i = 0; i < len; ++i) {
375                     NCURSES_CH_T value = ch;
376                     SetWidecExt(value, i);
377                     TR(TRACE_VIRTPUT, ("multicolumn %d:%d (%d,%d)",
378                                            i + 1, len,
379                                            win->_begy + y, win->_begx + x));
380                     line->text[x] = value;
381                     CHANGED_CELL(line, x);
382                     ++x;
383               }
384               goto testwrapping;
385           }
386     });
387 
388     /*
389      * Single-column characters.
390      */
391     line->text[x++] = ch;
392     /*
393      * This label is used only for wide-characters.
394      */
395     if_WIDEC(
396   testwrapping:
397     );
398 
399     TR(TRACE_VIRTPUT, ("cell (%ld, %ld..%d) = %s",
400                            (long) win->_cury, (long) win->_curx, x - 1,
401                            _tracech_t(CHREF(ch))));
402 
403     if (x > win->_maxx) {
404           return wrap_to_next_line(win);
405     }
406     win->_curx = (NCURSES_SIZE_T) x;
407     return OK;
408 }
409 
410 static NCURSES_INLINE int
waddch_nosync(WINDOW * win,const NCURSES_CH_T ch)411 waddch_nosync(WINDOW *win, const NCURSES_CH_T ch)
412 /* the workhorse function -- add a character to the given window */
413 {
414     NCURSES_SIZE_T x, y;
415     chtype t = (chtype) CharOf(ch);
416 #if USE_WIDEC_SUPPORT || NCURSES_SP_FUNCS || USE_REENTRANT
417     SCREEN *sp = _nc_screen_of(win);
418 #endif
419     const char *s = NCURSES_SP_NAME(unctrl) (NCURSES_SP_ARGx t);
420     int tabsize = 8;
421 
422     /*
423      * If we are using the alternate character set, forget about locale.
424      * Otherwise, if unctrl() returns a single-character or the locale
425      * claims the code is printable (and not also a control character),
426      * treat it that way.
427      */
428     if ((AttrOf(ch) & A_ALTCHARSET)
429           || (
430 #if USE_WIDEC_SUPPORT
431                  (sp != 0 && sp->_legacy_coding) &&
432 #endif
433                  s[1] == 0
434           )
435           || (
436                  (isprint((int) t) && !iscntrl((int) t))
437 #if USE_WIDEC_SUPPORT
438                  || ((sp == 0 || !sp->_legacy_coding) &&
439                        (WINDOW_EXT(win, addch_used)
440                         || !_nc_is_charable(CharOf(ch))))
441 #endif
442           )) {
443           return waddch_literal(win, ch);
444     }
445 
446     /*
447      * Handle carriage control and other codes that are not printable, or are
448      * known to expand to more than one character according to unctrl().
449      */
450     x = win->_curx;
451     y = win->_cury;
452     CHECK_POSITION(win, x, y);
453 
454     switch (t) {
455     case '\t':
456 #if USE_REENTRANT
457           tabsize = *ptrTabsize(sp);
458 #else
459           tabsize = TABSIZE;
460 #endif
461           x = (NCURSES_SIZE_T) (x + (tabsize - (x % tabsize)));
462           /*
463            * Space-fill the tab on the bottom line so that we'll get the
464            * "correct" cursor position.
465            */
466           if ((!win->_scroll && (y == win->_regbottom))
467               || (x <= win->_maxx)) {
468               NCURSES_CH_T blank = blankchar;
469               AddAttr(blank, AttrOf(ch));
470               while (win->_curx < x) {
471                     if (waddch_literal(win, blank) == ERR)
472                         return (ERR);
473               }
474               break;
475           } else {
476               wclrtoeol(win);
477               win->_flags |= _WRAPPED;
478               if (newline_forces_scroll(win, &y)) {
479                     x = win->_maxx;
480                     if (win->_scroll) {
481                         scroll(win);
482                         x = 0;
483                     }
484               } else {
485                     x = 0;
486               }
487           }
488           break;
489     case '\n':
490           wclrtoeol(win);
491           if (newline_forces_scroll(win, &y)) {
492               if (win->_scroll)
493                     scroll(win);
494               else
495                     return (ERR);
496           }
497           /* FALLTHRU */
498     case '\r':
499           x = 0;
500           win->_flags &= ~_WRAPPED;
501           break;
502     case '\b':
503           if (x == 0)
504               return (OK);
505           x--;
506           win->_flags &= ~_WRAPPED;
507           break;
508     default:
509           while (*s) {
510               NCURSES_CH_T sch;
511               SetChar(sch, UChar(*s++), AttrOf(ch));
512               if_EXT_COLORS(SetPair(sch, GetPair(ch)));
513               if (waddch_literal(win, sch) == ERR)
514                     return ERR;
515           }
516           return (OK);
517     }
518 
519     win->_curx = x;
520     win->_cury = y;
521 
522     return (OK);
523 }
524 
525 NCURSES_EXPORT(int)
_nc_waddch_nosync(WINDOW * win,const NCURSES_CH_T c)526 _nc_waddch_nosync(WINDOW *win, const NCURSES_CH_T c)
527 /* export copy of waddch_nosync() so the string-put functions can use it */
528 {
529     return (waddch_nosync(win, c));
530 }
531 
532 /*
533  * The versions below call _nc_synchook().  We wanted to avoid this in the
534  * version exported for string puts; they'll call _nc_synchook once at end
535  * of run.
536  */
537 
538 /* These are actual entry points */
539 
540 NCURSES_EXPORT(int)
waddch(WINDOW * win,const chtype ch)541 waddch(WINDOW *win, const chtype ch)
542 {
543     int code = ERR;
544     NCURSES_CH_T wch;
545     SetChar2(wch, ch);
546 
547     TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("waddch(%p, %s)"), (void *) win,
548                                               _tracechtype(ch)));
549 
550     if (win && (waddch_nosync(win, wch) != ERR)) {
551           _nc_synchook(win);
552           code = OK;
553     }
554 
555     TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
556     return (code);
557 }
558 
559 NCURSES_EXPORT(int)
wechochar(WINDOW * win,const chtype ch)560 wechochar(WINDOW *win, const chtype ch)
561 {
562     int code = ERR;
563     NCURSES_CH_T wch;
564     SetChar2(wch, ch);
565 
566     TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_CALLED("wechochar(%p, %s)"),
567                                               (void *) win,
568                                               _tracechtype(ch)));
569 
570     if (win && (waddch_nosync(win, wch) != ERR)) {
571           bool save_immed = win->_immed;
572           win->_immed = TRUE;
573           _nc_synchook(win);
574           win->_immed = save_immed;
575           code = OK;
576     }
577     TR(TRACE_VIRTPUT | TRACE_CCALLS, (T_RETURN("%d"), code));
578     return (code);
579 }
580