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         free(s->title);
 114         s->title = xstrdup(title);
 115 }
 116
 117 /* Resize screen. */
 118 void
 119 screen_resize(struct screen *s, u_int sx, u_int sy, int reflow)
 120 {
 121         if (sx < 1)
 122                 sx = 1;
 123         if (sy < 1)
 124                 sy = 1;
 125
 126         if (sx != screen_size_x(s)) {
 127                 screen_resize_x(s, sx);
 128
 129                 /*
 130                  * It is unclear what should happen to tabs on resize. xterm
 131                  * seems to try and maintain them, rxvt resets them. Resetting
 132                  * is simpler and more reliable so let's do that.
 133                  */
 134                 screen_reset_tabs(s);
 135         }
 136
 137         if (sy != screen_size_y(s))
 138                 screen_resize_y(s, sy);
 139
 140         if (reflow)
 141                 screen_reflow(s, sx);
 142 }
 143
 144 void
 145 screen_resize_x(struct screen *s, u_int sx)
 146 {
 147         struct grid             *gd = s->grid;
 148
 149         if (sx == 0)
 150                 fatalx("zero size");
 151
 152         /*
 153          * Treat resizing horizontally simply: just ensure the cursor is
 154          * on-screen and change the size. Don't bother to truncate any lines -
 155          * then the data should be accessible if the size is then incrased.
 156          *
 157          * The only potential wrinkle is if UTF-8 double-width characters are
 158          * left in the last column, but UTF-8 terminals should deal with this
 159          * sanely.
 160          */
 161         if (s->cx >= sx)
 162                 s->cx = sx - 1;
 163         gd->sx = sx;
 164 }
 165
 166 void
 167 screen_resize_y(struct screen *s, u_int sy)
 168 {
 169         struct grid     *gd = s->grid;
 170         u_int            needed, available, oldy, i;
 171
 172         if (sy == 0)
 173                 fatalx("zero size");
 174         oldy = screen_size_y(s);
 175
 176         /*
 177          * When resizing:
 178          *
 179          * If the height is decreasing, delete lines from the bottom until
 180          * hitting the cursor, then push lines from the top into the history.
 181          *
 182          * When increasing, pull as many lines as possible from the history to
 183          * the top, then fill the remaining with blanks at the bottom.
 184          */
 185
 186         /* Size decreasing. */
 187         if (sy < oldy) {
 188                 needed = oldy - sy;
 189
 190                 /* Delete as many lines as possible from the bottom. */
 191                 available = oldy - 1 - s->cy;
 192                 if (available > 0) {
 193                         if (available > needed)
 194                                 available = needed;
 195                         grid_view_delete_lines(gd, oldy - available, available);
 196                 }
 197                 needed -= available;
 198
 199                 /*
 200                  * Now just increase the history size, if possible, to take
 201                  * over the lines which are left. If history is off, delete
 202                  * lines from the top.
 203                  *
 204                  * XXX Should apply history limit?
 205                  */
 206                 available = s->cy;
 207                 if (gd->flags & GRID_HISTORY)
 208                         gd->hsize += needed;
 209                 else if (needed > 0 && available > 0) {
 210                         if (available > needed)
 211                                 available = needed;
 212                         grid_view_delete_lines(gd, 0, available);
 213                 }
 214                 s->cy -= needed;
 215         }
 216
 217         /* Resize line arrays. */
 218         gd->linedata = xrealloc(
 219             gd->linedata, gd->hsize + sy, sizeof *gd->linedata);
 220
 221         /* Size increasing. */
 222         if (sy > oldy) {
 223                 needed = sy - oldy;
 224
 225                 /*
 226                  * Try to pull as much as possible out of the history, if is
 227                  * is enabled.
 228                  */
 229                 available = gd->hsize;
 230                 if (gd->flags & GRID_HISTORY && available > 0) {
 231                         if (available > needed)
 232                                 available = needed;
 233                         gd->hsize -= available;
 234                         s->cy += available;
 235                 } else
 236                         available = 0;
 237                 needed -= available;
 238
 239                 /* Then fill the rest in with blanks. */
 240                 for (i = gd->hsize + sy - needed; i < gd->hsize + sy; i++)
 241                         memset(&gd->linedata[i], 0, sizeof gd->linedata[i]);
 242         }
 243
 244         /* Set the new size, and reset the scroll region. */
 245         gd->sy = sy;
 246         s->rupper = 0;
 247         s->rlower = screen_size_y(s) - 1;
 248 }
 249
 250 /* Set selection. */
 251 void
 252 screen_set_selection(struct screen *s, u_int sx, u_int sy,
 253     u_int ex, u_int ey, u_int rectflag, struct grid_cell *gc)
 254 {
 255         struct screen_sel       *sel = &s->sel;
 256
 257         memcpy(&sel->cell, gc, sizeof sel->cell);
 258         sel->flag = 1;
 259         sel->rectflag = rectflag;
 260
 261         sel->sx = sx; sel->sy = sy;
 262         sel->ex = ex; sel->ey = ey;
 263 }
 264
 265 /* Clear selection. */
 266 void
 267 screen_clear_selection(struct screen *s)
 268 {
 269         struct screen_sel       *sel = &s->sel;
 270
 271         sel->flag = 0;
 272 }
 273
 274 /* Check if cell in selection. */
 275 int
 276 screen_check_selection(struct screen *s, u_int px, u_int py)
 277 {
 278         struct screen_sel       *sel = &s->sel;
 279
 280         if (!sel->flag)
 281                 return (0);
 282
 283         if (sel->rectflag) {
 284                 if (sel->sy < sel->ey) {
 285                         /* start line < end line -- downward selection. */
 286                         if (py < sel->sy || py > sel->ey)
 287                                 return (0);
 288                 } else if (sel->sy > sel->ey) {
 289                         /* start line > end line -- upward selection. */
 290                         if (py > sel->sy || py < sel->ey)
 291                                 return (0);
 292                 } else {
 293                         /* starting line == ending line. */
 294                         if (py != sel->sy)
 295                                 return (0);
 296                 }
 297
 298                 /*
 299                  * Need to include the selection start row, but not the cursor
 300                  * row, which means the selection changes depending on which
 301                  * one is on the left.
 302                  */
 303                 if (sel->ex < sel->sx) {
 304                         /* Cursor (ex) is on the left. */
 305                         if (px < sel->ex)
 306                                 return (0);
 307
 308                         if (px > sel->sx)
 309                                 return (0);
 310                 } else {
 311                         /* Selection start (sx) is on the left. */
 312                         if (px < sel->sx)
 313                                 return (0);
 314
 315                         if (px > sel->ex)
 316                                 return (0);
 317                 }
 318         } else {
 319                 /*
 320                  * Like emacs, keep the top-left-most character, and drop the
 321                  * bottom-right-most, regardless of copy direction.
 322                  */
 323                 if (sel->sy < sel->ey) {
 324                         /* starting line < ending line -- downward selection. */
 325                         if (py < sel->sy || py > sel->ey)
 326                                 return (0);
 327
 328                         if ((py == sel->sy && px < sel->sx)
 329                             || (py == sel->ey && px > sel->ex))
 330                                 return (0);
 331                 } else if (sel->sy > sel->ey) {
 332                         /* starting line > ending line -- upward selection. */
 333                         if (py > sel->sy || py < sel->ey)
 334                                 return (0);
 335
 336                         if ((py == sel->sy && px >= sel->sx)
 337                             || (py == sel->ey && px < sel->ex))
 338                                 return (0);
 339                 } else {
 340                         /* starting line == ending line. */
 341                         if (py != sel->sy)
 342                                 return (0);
 343
 344                         if (sel->ex < sel->sx) {
 345                                 /* cursor (ex) is on the left */
 346                                 if (px > sel->sx || px < sel->ex)
 347                                         return (0);
 348                         } else {
 349                                 /* selection start (sx) is on the left */
 350                                 if (px < sel->sx || px > sel->ex)
 351                                         return (0);
 352                         }
 353                 }
 354         }
 355
 356         return (1);
 357 }
 358
 359 /* Reflow wrapped lines. */
 360 void
 361 screen_reflow(struct screen *s, u_int new_x)
 362 {
 363         struct grid     *old = s->grid;
 364         u_int            change;
 365
 366         s->grid = grid_create(old->sx, old->sy, old->hlimit);
 367
 368         change = grid_reflow(s->grid, old, new_x);
 369         if (change < s->cy)
 370                 s->cy -= change;
 371         else
 372                 s->cy = 0;
 373 }