Utilities/cmpdcurses/pdcurses/bkgd.c

   1 /* PDCurses */
   2
   3 #include <curspriv.h>
   4
   5 /*man-start**************************************************************
   6
   7 bkgd
   8 ----
   9
  10 ### Synopsis
  11
  12     int bkgd(chtype ch);
  13     void bkgdset(chtype ch);
  14     chtype getbkgd(WINDOW *win);
  15     int wbkgd(WINDOW *win, chtype ch);
  16     void wbkgdset(WINDOW *win, chtype ch);
  17
  18     int bkgrnd(const cchar_t *wch);
  19     void bkgrndset(const cchar_t *wch);
  20     int getbkgrnd(cchar_t *wch);
  21     int wbkgrnd(WINDOW *win, const cchar_t *wch);
  22     void wbkgrndset(WINDOW *win, const cchar_t *wch);
  23     int wgetbkgrnd(WINDOW *win, cchar_t *wch);
  24
  25 ### Description
  26
  27    bkgdset() and wbkgdset() manipulate the background of a window. The
  28    background is a chtype consisting of any combination of attributes
  29    and a character; it is combined with each chtype added or inserted to
  30    the window by waddch() or winsch(). Only the attribute part is used
  31    to set the background of non-blank characters, while both character
  32    and attributes are used for blank positions.
  33
  34    bkgd() and wbkgd() not only change the background, but apply it
  35    immediately to every cell in the window.
  36
  37    wbkgrnd(), wbkgrndset() and wgetbkgrnd() are the "wide-character"
  38    versions of these functions, taking a pointer to a cchar_t instead of
  39    a chtype. However, in PDCurses, cchar_t and chtype are the same.
  40
  41    The attributes that are defined with the attrset()/attron() set of
  42    functions take precedence over the background attributes if there is
  43    a conflict (e.g., different color pairs).
  44
  45 ### Return Value
  46
  47    bkgd() and wbkgd() return OK, unless the window is NULL, in which
  48    case they return ERR.
  49
  50 ### Portability
  51                              X/Open  ncurses  NetBSD
  52     bkgd                        Y       Y       Y
  53     bkgdset                     Y       Y       Y
  54     getbkgd                     Y       Y       Y
  55     wbkgd                       Y       Y       Y
  56     wbkgdset                    Y       Y       Y
  57     bkgrnd                      Y       Y       Y
  58     bkgrndset                   Y       Y       Y
  59     getbkgrnd                   Y       Y       Y
  60     wbkgrnd                     Y       Y       Y
  61     wbkgrndset                  Y       Y       Y
  62     wgetbkgrnd                  Y       Y       Y
  63
  64 **man-end****************************************************************/
  65
  66 int wbkgd(WINDOW *win, chtype ch)
  67 {
  68     int x, y;
  69     chtype oldcolr, oldch, newcolr, newch, colr, attr;
  70     chtype oldattr = 0, newattr = 0;
  71     chtype *winptr;
  72
  73     PDC_LOG(("wbkgd() - called\n"));
  74
  75     if (!win)
  76         return ERR;
  77
  78     if (win->_bkgd == ch)
  79         return OK;
  80
  81     oldcolr = win->_bkgd & A_COLOR;
  82     if (oldcolr)
  83         oldattr = (win->_bkgd & A_ATTRIBUTES) ^ oldcolr;
  84
  85     oldch = win->_bkgd & A_CHARTEXT;
  86
  87     wbkgdset(win, ch);
  88
  89     newcolr = win->_bkgd & A_COLOR;
  90     if (newcolr)
  91         newattr = (win->_bkgd & A_ATTRIBUTES) ^ newcolr;
  92
  93     newch = win->_bkgd & A_CHARTEXT;
  94
  95     /* what follows is what seems to occur in the System V
  96        implementation of this routine */
  97
  98     for (y = 0; y < win->_maxy; y++)
  99     {
 100         for (x = 0; x < win->_maxx; x++)
 101         {
 102             winptr = win->_y[y] + x;
 103
 104             ch = *winptr;
 105
 106             /* determine the colors and attributes of the character read
 107                from the window */
 108
 109             colr = ch & A_COLOR;
 110             attr = ch & (A_ATTRIBUTES ^ A_COLOR);
 111
 112             /* if the color is the same as the old background color,
 113                then make it the new background color, otherwise leave it */
 114
 115             if (colr == oldcolr)
 116                 colr = newcolr;
 117
 118             /* remove any attributes (non color) from the character that
 119                were part of the old background, then combine the
 120                remaining ones with the new background */
 121
 122             attr ^= oldattr;
 123             attr |= newattr;
 124
 125             /* change character if it is there because it was the old
 126                background character */
 127
 128             ch &= A_CHARTEXT;
 129             if (ch == oldch)
 130                 ch = newch;
 131
 132             ch |= (attr | colr);
 133
 134             *winptr = ch;
 135
 136         }
 137     }
 138
 139     touchwin(win);
 140     PDC_sync(win);
 141     return OK;
 142 }
 143
 144 int bkgd(chtype ch)
 145 {
 146     PDC_LOG(("bkgd() - called\n"));
 147
 148     return wbkgd(stdscr, ch);
 149 }
 150
 151 void wbkgdset(WINDOW *win, chtype ch)
 152 {
 153     PDC_LOG(("wbkgdset() - called\n"));
 154
 155     if (win)
 156     {
 157         if (!(ch & A_CHARTEXT))
 158             ch |= ' ';
 159
 160         win->_bkgd = ch;
 161     }
 162 }
 163
 164 void bkgdset(chtype ch)
 165 {
 166     PDC_LOG(("bkgdset() - called\n"));
 167
 168     wbkgdset(stdscr, ch);
 169 }
 170
 171 chtype getbkgd(WINDOW *win)
 172 {
 173     PDC_LOG(("getbkgd() - called\n"));
 174
 175     return win ? win->_bkgd : (chtype)ERR;
 176 }
 177
 178 #ifdef PDC_WIDE
 179 int wbkgrnd(WINDOW *win, const cchar_t *wch)
 180 {
 181     PDC_LOG(("wbkgrnd() - called\n"));
 182
 183     return wch ? wbkgd(win, *wch) : ERR;
 184 }
 185
 186 int bkgrnd(const cchar_t *wch)
 187 {
 188     PDC_LOG(("bkgrnd() - called\n"));
 189
 190     return wbkgrnd(stdscr, wch);
 191 }
 192
 193 void wbkgrndset(WINDOW *win, const cchar_t *wch)
 194 {
 195     PDC_LOG(("wbkgdset() - called\n"));
 196
 197     if (wch)
 198         wbkgdset(win, *wch);
 199 }
 200
 201 void bkgrndset(const cchar_t *wch)
 202 {
 203     PDC_LOG(("bkgrndset() - called\n"));
 204
 205     wbkgrndset(stdscr, wch);
 206 }
 207
 208 int wgetbkgrnd(WINDOW *win, cchar_t *wch)
 209 {
 210     PDC_LOG(("wgetbkgrnd() - called\n"));
 211
 212     if (!win || !wch)
 213         return ERR;
 214
 215     *wch = win->_bkgd;
 216
 217     return OK;
 218 }
 219
 220 int getbkgrnd(cchar_t *wch)
 221 {
 222     PDC_LOG(("getbkgrnd() - called\n"));
 223
 224     return wgetbkgrnd(stdscr, wch);
 225 }
 226 #endif