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         free(s->tabs);
  74         free(s->title);
  75         free(s->ccolour);
  76         grid_destroy(s->grid);
  77 }
  78
  79 /* Reset tabs to default, eight spaces apart. */
  80 void
  81 screen_reset_tabs(struct screen *s)
  82 {
  83         u_int   i;
  84
  85         free(s->tabs);
  86
  87         if ((s->tabs = bit_alloc(screen_size_x(s))) == NULL)
  88                 fatal("bit_alloc failed");
  89         for (i = 8; i < screen_size_x(s); i += 8)
  90                 bit_set(s->tabs, i);
  91 }
  92
  93 /* Set screen cursor style. */
  94 void
  95 screen_set_cursor_style(struct screen *s, u_int style)
  96 {
  97         if (style <= 6)
  98                 s->cstyle = style;
  99 }
 100
 101 /* Set screen cursor colour. */
 102 void
 103 screen_set_cursor_colour(struct screen *s, const char *colour_string)
 104 {
 105         free(s->ccolour);
 106         s->ccolour = xstrdup(colour_string);
 107 }
 108
 109 /* Set screen title. */
 110 void
 111 screen_set_title(struct screen *s, const char *title)
 112 {
 113         char    tmp[BUFSIZ];
 114
 115         strlcpy(tmp, title, sizeof tmp);
 116
 117         free(s->title);
 118         s->title = xstrdup(tmp);
 119 }
 120
 121 /* Resize screen. */
 122 void
 123 screen_resize(struct screen *s, u_int sx, u_int sy, int reflow)
 124 {
 125         if (sx < 1)
 126                 sx = 1;
 127         if (sy < 1)
 128                 sy = 1;
 129
 130         if (sx != screen_size_x(s)) {
 131                 screen_resize_x(s, sx);
 132
 133                 /*
 134                  * It is unclear what should happen to tabs on resize. xterm
 135                  * seems to try and maintain them, rxvt resets them. Resetting
 136                  * is simpler and more reliable so let's do that.
 137                  */
 138                 screen_reset_tabs(s);
 139         }
 140
 141         if (sy != screen_size_y(s))
 142                 screen_resize_y(s, sy);
 143
 144         if (reflow)
 145                 screen_reflow(s, sx);
 146 }
 147
 148 void
 149 screen_resize_x(struct screen *s, u_int sx)
 150 {
 151         struct grid             *gd = s->grid;
 152
 153         if (sx == 0)
 154                 fatalx("zero size");
 155
 156         /*
 157          * Treat resizing horizontally simply: just ensure the cursor is
 158          * on-screen and change the size. Don't bother to truncate any lines -
 159          * then the data should be accessible if the size is then incrased.
 160          *
 161          * The only potential wrinkle is if UTF-8 double-width characters are
 162          * left in the last column, but UTF-8 terminals should deal with this
 163          * sanely.
 164          */
 165         if (s->cx >= sx)
 166                 s->cx = sx - 1;
 167         gd->sx = sx;
 168 }
 169
 170 void
 171 screen_resize_y(struct screen *s, u_int sy)
 172 {
 173         struct grid     *gd = s->grid;
 174         u_int            needed, available, oldy, i;
 175
 176         if (sy == 0)
 177                 fatalx("zero size");
 178         oldy = screen_size_y(s);
 179
 180         /*
 181          * When resizing:
 182          *
 183          * If the height is decreasing, delete lines from the bottom until
 184          * hitting the cursor, then push lines from the top into the history.
 185          *
 186          * When increasing, pull as many lines as possible from the history to
 187          * the top, then fill the remaining with blanks at the bottom.
 188          */
 189
 190         /* Size decreasing. */
 191         if (sy < oldy) {
 192                 needed = oldy - sy;
 193
 194                 /* Delete as many lines as possible from the bottom. */
 195                 available = oldy - 1 - s->cy;
 196                 if (available > 0) {
 197                         if (available > needed)
 198                                 available = needed;
 199                         grid_view_delete_lines(gd, oldy - available, available);
 200                 }
 201                 needed -= available;
 202
 203                 /*
 204                  * Now just increase the history size, if possible, to take
 205                  * over the lines which are left. If history is off, delete
 206                  * lines from the top.
 207                  *
 208                  * XXX Should apply history limit?
 209                  */
 210                 available = s->cy;
 211                 if (gd->flags & GRID_HISTORY)
 212                         gd->hsize += needed;
 213                 else if (needed > 0 && available > 0) {
 214                         if (available > needed)
 215                                 available = needed;
 216                         grid_view_delete_lines(gd, 0, available);
 217                 }
 218                 s->cy -= needed;
 219         }
 220
 221         /* Resize line arrays. */
 222         gd->linedata = xrealloc(
 223             gd->linedata, gd->hsize + sy, sizeof *gd->linedata);
 224
 225         /* Size increasing. */
 226         if (sy > oldy) {
 227                 needed = sy - oldy;
 228
 229                 /*
 230                  * Try to pull as much as possible out of the history, if is
 231                  * is enabled.
 232                  */
 233                 available = gd->hsize;
 234                 if (gd->flags & GRID_HISTORY && available > 0) {
 235                         if (available > needed)
 236                                 available = needed;
 237                         gd->hsize -= available;
 238                         s->cy += available;
 239                 } else
 240                         available = 0;
 241                 needed -= available;
 242
 243                 /* Then fill the rest in with blanks. */
 244                 for (i = gd->hsize + sy - needed; i < gd->hsize + sy; i++)
 245                         memset(&gd->linedata[i], 0, sizeof gd->linedata[i]);
 246         }
 247
 248         /* Set the new size, and reset the scroll region. */
 249         gd->sy = sy;
 250         s->rupper = 0;
 251         s->rlower = screen_size_y(s) - 1;
 252 }
 253
 254 /* Set selection. */
 255 void
 256 screen_set_selection(struct screen *s, u_int sx, u_int sy,
 257     u_int ex, u_int ey, u_int rectflag, struct grid_cell *gc)
 258 {
 259         struct screen_sel       *sel = &s->sel;
 260
 261         memcpy(&sel->cell, gc, sizeof sel->cell);
 262         sel->flag = 1;
 263         sel->rectflag = rectflag;
 264
 265         sel->sx = sx; sel->sy = sy;
 266         sel->ex = ex; sel->ey = ey;
 267 }
 268
 269 /* Clear selection. */
 270 void
 271 screen_clear_selection(struct screen *s)
 272 {
 273         struct screen_sel       *sel = &s->sel;
 274
 275         sel->flag = 0;
 276 }
 277
 278 /* Check if cell in selection. */
 279 int
 280 screen_check_selection(struct screen *s, u_int px, u_int py)
 281 {
 282         struct screen_sel       *sel = &s->sel;
 283
 284         if (!sel->flag)
 285                 return (0);
 286
 287         if (sel->rectflag) {
 288                 if (sel->sy < sel->ey) {
 289                         /* start line < end line -- downward selection. */
 290                         if (py < sel->sy || py > sel->ey)
 291                                 return (0);
 292                 } else if (sel->sy > sel->ey) {
 293                         /* start line > end line -- upward selection. */
 294                         if (py > sel->sy || py < sel->ey)
 295                                 return (0);
 296                 } else {
 297                         /* starting line == ending line. */
 298                         if (py != sel->sy)
 299                                 return (0);
 300                 }
 301
 302                 /*
 303                  * Need to include the selection start row, but not the cursor
 304                  * row, which means the selection changes depending on which
 305                  * one is on the left.
 306                  */
 307                 if (sel->ex < sel->sx) {
 308                         /* Cursor (ex) is on the left. */
 309                         if (px < sel->ex)
 310                                 return (0);
 311
 312                         if (px > sel->sx)
 313                                 return (0);
 314                 } else {
 315                         /* Selection start (sx) is on the left. */
 316                         if (px < sel->sx)
 317                                 return (0);
 318
 319                         if (px > sel->ex)
 320                                 return (0);
 321                 }
 322         } else {
 323                 /*
 324                  * Like emacs, keep the top-left-most character, and drop the
 325                  * bottom-right-most, regardless of copy direction.
 326                  */
 327                 if (sel->sy < sel->ey) {
 328                         /* starting line < ending line -- downward selection. */
 329                         if (py < sel->sy || py > sel->ey)
 330                                 return (0);
 331
 332                         if ((py == sel->sy && px < sel->sx)
 333                             || (py == sel->ey && px > sel->ex))
 334                                 return (0);
 335                 } else if (sel->sy > sel->ey) {
 336                         /* starting line > ending line -- upward selection. */
 337                         if (py > sel->sy || py < sel->ey)
 338                                 return (0);
 339
 340                         if ((py == sel->sy && px >= sel->sx)
 341                             || (py == sel->ey && px < sel->ex))
 342                                 return (0);
 343                 } else {
 344                         /* starting line == ending line. */
 345                         if (py != sel->sy)
 346                                 return (0);
 347
 348                         if (sel->ex < sel->sx) {
 349                                 /* cursor (ex) is on the left */
 350                                 if (px > sel->sx || px < sel->ex)
 351                                         return (0);
 352                         } else {
 353                                 /* selection start (sx) is on the left */
 354                                 if (px < sel->sx || px > sel->ex)
 355                                         return (0);
 356                         }
 357                 }
 358         }
 359
 360         return (1);
 361 }
 362
 363 /* Reflow wrapped lines. */
 364 void
 365 screen_reflow(struct screen *s, u_int new_x)
 366 {
 367         struct grid     *old = s->grid;
 368
 369         s->grid = grid_create(old->sx, old->sy, old->hlimit);
 370         s->cy -= grid_reflow(s->grid, old, new_x);
 371 }