screen.c

   1 /* $OpenBSD$ */
   2
   3 /*
   4  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
  15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <sys/types.h>
  20
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <unistd.h>
  24
  25 #include "tmux.h"
  26
  27 void    screen_resize_x(struct screen *, u_int);
  28 void    screen_resize_y(struct screen *, u_int);
  29
  30 /* Create a new screen. */
  31 void
  32 screen_init(struct screen *s, u_int sx, u_int sy, u_int hlimit)
  33 {
  34         char hn[MAXHOSTNAMELEN];
  35
  36         s->grid = grid_create(sx, sy, hlimit);
  37
  38         if (gethostname(hn, MAXHOSTNAMELEN) == 0)
  39                 s->title = xstrdup(hn);
  40         else
  41                 s->title = xstrdup("");
  42
  43         s->cstyle = 0;
  44         s->ccolour = xstrdup("");
  45         s->tabs = NULL;
  46
  47         screen_reinit(s);
  48 }
  49
  50 /* Reinitialise screen. */
  51 void
  52 screen_reinit(struct screen *s)
  53 {
  54         s->cx = 0;
  55         s->cy = 0;
  56
  57         s->rupper = 0;
  58         s->rlower = screen_size_y(s) - 1;
  59
  60         s->mode = MODE_CURSOR | MODE_WRAP;
  61
  62         screen_reset_tabs(s);
  63
  64         grid_clear_lines(s->grid, s->grid->hsize, s->grid->sy);
  65
  66         screen_clear_selection(s);
  67 }
  68
  69 /* Destroy a screen. */
  70 void
  71 screen_free(struct screen *s)
  72 {
  73         if (s->tabs != NULL)
  74                 xfree(s->tabs);
  75         xfree(s->title);
  76         xfree(s->ccolour);
  77         grid_destroy(s->grid);
  78 }
  79
  80 /* Reset tabs to default, eight spaces apart. */
  81 void
  82 screen_reset_tabs(struct screen *s)
  83 {
  84         u_int   i;
  85
  86         if (s->tabs != NULL)
  87                 xfree(s->tabs);
  88
  89         if ((s->tabs = bit_alloc(screen_size_x(s))) == NULL)
  90                 fatal("bit_alloc failed");
  91         for (i = 8; i < screen_size_x(s); i += 8)
  92                 bit_set(s->tabs, i);
  93 }
  94
  95 /* Set screen cursor style. */
  96 void
  97 screen_set_cursor_style(struct screen *s, u_int style)
  98 {
  99         if (style <= 6)
 100                 s->cstyle = style;
 101 }
 102
 103 /* Set screen cursor colour. */
 104 void
 105 screen_set_cursor_colour(struct screen *s, const char *colour_string)
 106 {
 107         xfree(s->ccolour);
 108         s->ccolour = xstrdup(colour_string);
 109 }
 110
 111 /* Set screen title. */
 112 void
 113 screen_set_title(struct screen *s, const char *title)
 114 {
 115         char    tmp[BUFSIZ];
 116
 117         strlcpy(tmp, title, sizeof tmp);
 118
 119         xfree(s->title);
 120         s->title = xstrdup(tmp);
 121 }
 122
 123 /* Resize screen. */
 124 void
 125 screen_resize(struct screen *s, u_int sx, u_int sy)
 126 {
 127         if (sx < 1)
 128                 sx = 1;
 129         if (sy < 1)
 130                 sy = 1;
 131
 132         if (sx != screen_size_x(s)) {
 133                 screen_resize_x(s, sx);
 134
 135                 /*
 136                  * It is unclear what should happen to tabs on resize. xterm
 137                  * seems to try and maintain them, rxvt resets them. Resetting
 138                  * is simpler and more reliable so let's do that.
 139                  */
 140                 screen_reset_tabs(s);
 141         }
 142
 143         if (sy != screen_size_y(s))
 144                 screen_resize_y(s, sy);
 145 }
 146
 147 void
 148 screen_resize_x(struct screen *s, u_int sx)
 149 {
 150         struct grid             *gd = s->grid;
 151
 152         if (sx == 0)
 153                 fatalx("zero size");
 154
 155         /*
 156          * Treat resizing horizontally simply: just ensure the cursor is
 157          * on-screen and change the size. Don't bother to truncate any lines -
 158          * then the data should be accessible if the size is then incrased.
 159          *
 160          * The only potential wrinkle is if UTF-8 double-width characters are
 161          * left in the last column, but UTF-8 terminals should deal with this
 162          * sanely.
 163          */
 164         if (s->cx >= sx)
 165                 s->cx = sx - 1;
 166         gd->sx = sx;
 167 }
 168
 169 void
 170 screen_resize_y(struct screen *s, u_int sy)
 171 {
 172         struct grid     *gd = s->grid;
 173         u_int            needed, available, oldy, i;
 174
 175         if (sy == 0)
 176                 fatalx("zero size");
 177         oldy = screen_size_y(s);
 178
 179         /*
 180          * When resizing:
 181          *
 182          * If the height is decreasing, delete lines from the bottom until
 183          * hitting the cursor, then push lines from the top into the history.
 184          *
 185          * When increasing, pull as many lines as possible from the history to
 186          * the top, then fill the remaining with blanks at the bottom.
 187          */
 188
 189         /* Size decreasing. */
 190         if (sy < oldy) {
 191                 needed = oldy - sy;
 192
 193                 /* Delete as many lines as possible from the bottom. */
 194                 available = oldy - 1 - s->cy;
 195                 if (available > 0) {
 196                         if (available > needed)
 197                                 available = needed;
 198                         grid_view_delete_lines(gd, oldy - available, available);
 199                 }
 200                 needed -= available;
 201
 202                 /*
 203                  * Now just increase the history size, if possible, to take
 204                  * over the lines which are left. If history is off, delete
 205                  * lines from the top.
 206                  *
 207                  * XXX Should apply history limit?
 208                  */
 209                 available = s->cy;
 210                 if (gd->flags & GRID_HISTORY)
 211                         gd->hsize += needed;
 212                 else if (needed > 0 && available > 0) {
 213                         if (available > needed)
 214                                 available = needed;
 215                         grid_view_delete_lines(gd, 0, available);
 216                 }
 217                 s->cy -= needed;
 218         }
 219
 220         /* Resize line arrays. */
 221         gd->linedata = xrealloc(
 222             gd->linedata, gd->hsize + sy, sizeof *gd->linedata);
 223
 224         /* Size increasing. */
 225         if (sy > oldy) {
 226                 needed = sy - oldy;
 227
 228                 /*
 229                  * Try to pull as much as possible out of the history, if is
 230                  * is enabled.
 231                  */
 232                 available = gd->hsize;
 233                 if (gd->flags & GRID_HISTORY && available > 0) {
 234                         if (available > needed)
 235                                 available = needed;
 236                         gd->hsize -= available;
 237                         s->cy += available;
 238                 } else
 239                         available = 0;
 240                 needed -= available;
 241
 242                 /* Then fill the rest in with blanks. */
 243                 for (i = gd->hsize + sy - needed; i < gd->hsize + sy; i++)
 244                         memset(&gd->linedata[i], 0, sizeof gd->linedata[i]);
 245         }
 246
 247         /* Set the new size, and reset the scroll region. */
 248         gd->sy = sy;
 249         s->rupper = 0;
 250         s->rlower = screen_size_y(s) - 1;
 251 }
 252
 253 /* Set selection. */
 254 void
 255 screen_set_selection(struct screen *s, u_int sx, u_int sy,
 256     u_int ex, u_int ey, u_int rectflag, struct grid_cell *gc)
 257 {
 258         struct screen_sel       *sel = &s->sel;
 259
 260         memcpy(&sel->cell, gc, sizeof sel->cell);
 261         sel->flag = 1;
 262         sel->rectflag = rectflag;
 263
 264         sel->sx = sx; sel->sy = sy;
 265         sel->ex = ex; sel->ey = ey;
 266 }
 267
 268 /* Clear selection. */
 269 void
 270 screen_clear_selection(struct screen *s)
 271 {
 272         struct screen_sel       *sel = &s->sel;
 273
 274         sel->flag = 0;
 275 }
 276
 277 /* Check if cell in selection. */
 278 int
 279 screen_check_selection(struct screen *s, u_int px, u_int py)
 280 {
 281         struct screen_sel       *sel = &s->sel;
 282
 283         if (!sel->flag)
 284                 return (0);
 285
 286         if (sel->rectflag) {
 287                 if (sel->sy < sel->ey) {
 288                         /* start line < end line -- downward selection. */
 289                         if (py < sel->sy || py > sel->ey)
 290                                 return (0);
 291                 } else if (sel->sy > sel->ey) {
 292                         /* start line > end line -- upward selection. */
 293                         if (py > sel->sy || py < sel->ey)
 294                                 return (0);
 295                 } else {
 296                         /* starting line == ending line. */
 297                         if (py != sel->sy)
 298                                 return (0);
 299                 }
 300
 301                 /*
 302                  * Need to include the selection start row, but not the cursor
 303                  * row, which means the selection changes depending on which
 304                  * one is on the left.
 305                  */
 306                 if (sel->ex < sel->sx) {
 307                         /* Cursor (ex) is on the left. */
 308                         if (px < sel->ex)
 309                                 return (0);
 310
 311                         if (px > sel->sx)
 312                                 return (0);
 313                 } else {
 314                         /* Selection start (sx) is on the left. */
 315                         if (px < sel->sx)
 316                                 return (0);
 317
 318                         if (px > sel->ex)
 319                                 return (0);
 320                 }
 321         } else {
 322                 /*
 323                  * Like emacs, keep the top-left-most character, and drop the
 324                  * bottom-right-most, regardless of copy direction.
 325                  */
 326                 if (sel->sy < sel->ey) {
 327                         /* starting line < ending line -- downward selection. */
 328                         if (py < sel->sy || py > sel->ey)
 329                                 return (0);
 330
 331                         if ((py == sel->sy && px < sel->sx)
 332                             || (py == sel->ey && px > sel->ex))
 333                                 return (0);
 334                 } else if (sel->sy > sel->ey) {
 335                         /* starting line > ending line -- upward selection. */
 336                         if (py > sel->sy || py < sel->ey)
 337                                 return (0);
 338
 339                         if ((py == sel->sy && px >= sel->sx)
 340                             || (py == sel->ey && px < sel->ex))
 341                                 return (0);
 342                 } else {
 343                         /* starting line == ending line. */
 344                         if (py != sel->sy)
 345                                 return (0);
 346
 347                         if (sel->ex < sel->sx) {
 348                                 /* cursor (ex) is on the left */
 349                                 if (px > sel->sx || px < sel->ex)
 350                                         return (0);
 351                         } else {
 352                                 /* selection start (sx) is on the left */
 353                                 if (px < sel->sx || px > sel->ex)
 354                                         return (0);
 355                         }
 356                 }
 357         }
 358
 359         return (1);
 360 }