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 #include <vis.h>
  25
  26 #include "tmux.h"
  27
  28 void    screen_resize_x(struct screen *, u_int);
  29 void    screen_resize_y(struct screen *, u_int);
  30
  31 /* Create a new screen. */
  32 void
  33 screen_init(struct screen *s, u_int sx, u_int sy, u_int hlimit)
  34 {
  35         char hn[MAXHOSTNAMELEN];
  36
  37         s->grid = grid_create(sx, sy, hlimit);
  38
  39         if (gethostname(hn, MAXHOSTNAMELEN) == 0)
  40                 s->title = xstrdup(hn);
  41         else
  42                 s->title = xstrdup("");
  43
  44         s->tabs = NULL;
  45
  46         screen_reinit(s);
  47 }
  48
  49 /* Reinitialise screen. */
  50 void
  51 screen_reinit(struct screen *s)
  52 {
  53         s->cx = 0;
  54         s->cy = 0;
  55
  56         s->rupper = 0;
  57         s->rlower = screen_size_y(s) - 1;
  58
  59         s->mode = MODE_CURSOR | MODE_WRAP;
  60
  61         screen_reset_tabs(s);
  62
  63         grid_clear_lines(s->grid, s->grid->hsize, s->grid->sy);
  64
  65         screen_clear_selection(s);
  66 }
  67
  68 /* Destroy a screen. */
  69 void
  70 screen_free(struct screen *s)
  71 {
  72         if (s->tabs != NULL)
  73                 xfree(s->tabs);
  74         xfree(s->title);
  75         grid_destroy(s->grid);
  76 }
  77
  78 /* Reset tabs to default, eight spaces apart. */
  79 void
  80 screen_reset_tabs(struct screen *s)
  81 {
  82         u_int   i;
  83
  84         if (s->tabs != NULL)
  85                 xfree(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 title. */
  94 void
  95 screen_set_title(struct screen *s, const char *title)
  96 {
  97         char    tmp[BUFSIZ];
  98
  99         strnvis(tmp, title, sizeof tmp, VIS_OCTAL|VIS_TAB|VIS_NL);
 100
 101         xfree(s->title);
 102         s->title = xstrdup(tmp);
 103 }
 104
 105 /* Resize screen. */
 106 void
 107 screen_resize(struct screen *s, u_int sx, u_int sy)
 108 {
 109         if (sx < 1)
 110                 sx = 1;
 111         if (sy < 1)
 112                 sy = 1;
 113
 114         if (sx != screen_size_x(s)) {
 115                 screen_resize_x(s, sx);
 116
 117                 /*
 118                  * It is unclear what should happen to tabs on resize. xterm
 119                  * seems to try and maintain them, rxvt resets them. Resetting
 120                  * is simpler and more reliable so let's do that.
 121                  */
 122                 screen_reset_tabs(s);
 123         }
 124
 125         if (sy != screen_size_y(s))
 126                 screen_resize_y(s, sy);
 127 }
 128
 129 void
 130 screen_resize_x(struct screen *s, u_int sx)
 131 {
 132         struct grid             *gd = s->grid;
 133
 134         if (sx == 0)
 135                 fatalx("zero size");
 136
 137         /*
 138          * Treat resizing horizontally simply: just ensure the cursor is
 139          * on-screen and change the size. Don't bother to truncate any lines -
 140          * then the data should be accessible if the size is then incrased.
 141          *
 142          * The only potential wrinkle is if UTF-8 double-width characters are
 143          * left in the last column, but UTF-8 terminals should deal with this
 144          * sanely.
 145          */
 146         if (s->cx >= sx)
 147                 s->cx = sx - 1;
 148         gd->sx = sx;
 149 }
 150
 151 void
 152 screen_resize_y(struct screen *s, u_int sy)
 153 {
 154         struct grid     *gd = s->grid;
 155         u_int            needed, available, oldy, i;
 156
 157         if (sy == 0)
 158                 fatalx("zero size");
 159         oldy = screen_size_y(s);
 160
 161         /*
 162          * When resizing:
 163          *
 164          * If the height is decreasing, delete lines from the bottom until
 165          * hitting the cursor, then push lines from the top into the history.
 166          *
 167          * When increasing, pull as many lines as possible from the history to
 168          * the top, then fill the remaining with blanks at the bottom.
 169          */
 170
 171         /* Size decreasing. */
 172         if (sy < oldy) {
 173                 needed = oldy - sy;
 174
 175                 /* Delete as many lines as possible from the bottom. */
 176                 available = oldy - 1 - s->cy;
 177                 if (available > 0) {
 178                         if (available > needed)
 179                                 available = needed;
 180                         grid_view_delete_lines(gd, oldy - available, available);
 181                 }
 182                 needed -= available;
 183
 184                 /*
 185                  * Now just increase the history size, if possible, to take
 186                  * over the lines which are left. If history is off, delete
 187                  * lines from the top.
 188                  *
 189                  * XXX Should apply history limit?
 190                  */
 191                 available = s->cy;
 192                 if (gd->flags & GRID_HISTORY)
 193                         gd->hsize += needed;
 194                 else if (needed > 0 && available > 0) {
 195                         if (available > needed)
 196                                 available = needed;
 197                         grid_view_delete_lines(gd, 0, available);
 198                 }
 199                 s->cy -= needed;
 200         }
 201
 202         /* Resize line arrays. */
 203         gd->linedata = xrealloc(
 204             gd->linedata, gd->hsize + sy, sizeof *gd->linedata);
 205
 206         /* Size increasing. */
 207         if (sy > oldy) {
 208                 needed = sy - oldy;
 209
 210                 /*
 211                  * Try to pull as much as possible out of the history, if is
 212                  * is enabled.
 213                  */
 214                 available = gd->hsize;
 215                 if (gd->flags & GRID_HISTORY && available > 0) {
 216                         if (available > needed)
 217                                 available = needed;
 218                         gd->hsize -= available;
 219                         s->cy += available;
 220                 } else
 221                         available = 0;
 222                 needed -= available;
 223
 224                 /* Then fill the rest in with blanks. */
 225                 for (i = gd->hsize + sy - needed; i < gd->hsize + sy; i++)
 226                         memset(&gd->linedata[i], 0, sizeof gd->linedata[i]);
 227         }
 228
 229         /* Set the new size, and reset the scroll region. */
 230         gd->sy = sy;
 231         s->rupper = 0;
 232         s->rlower = screen_size_y(s) - 1;
 233 }
 234
 235 /* Set selection. */
 236 void
 237 screen_set_selection(struct screen *s, u_int sx, u_int sy,
 238     u_int ex, u_int ey, u_int rectflag, struct grid_cell *gc)
 239 {
 240         struct screen_sel       *sel = &s->sel;
 241
 242         memcpy(&sel->cell, gc, sizeof sel->cell);
 243         sel->flag = 1;
 244         sel->rectflag = rectflag;
 245
 246         sel->sx = sx; sel->sy = sy;
 247         sel->ex = ex; sel->ey = ey;
 248 }
 249
 250 /* Clear selection. */
 251 void
 252 screen_clear_selection(struct screen *s)
 253 {
 254         struct screen_sel       *sel = &s->sel;
 255
 256         sel->flag = 0;
 257 }
 258
 259 /* Check if cell in selection. */
 260 int
 261 screen_check_selection(struct screen *s, u_int px, u_int py)
 262 {
 263         struct screen_sel       *sel = &s->sel;
 264
 265         if (!sel->flag)
 266                 return (0);
 267
 268         if (sel->rectflag) {
 269                 if (sel->sy < sel->ey) {
 270                         /* start line < end line -- downward selection. */
 271                         if (py < sel->sy || py > sel->ey)
 272                                 return (0);
 273                 } else if (sel->sy > sel->ey) {
 274                         /* start line > end line -- upward selection. */
 275                         if (py > sel->sy || py < sel->ey)
 276                                 return (0);
 277                 } else {
 278                         /* starting line == ending line. */
 279                         if (py != sel->sy)
 280                                 return (0);
 281                 }
 282
 283                 /*
 284                  * Need to include the selection start row, but not the cursor
 285                  * row, which means the selection changes depending on which
 286                  * one is on the left.
 287                  */
 288                 if (sel->ex < sel->sx) {
 289                         /* Cursor (ex) is on the left. */
 290                         if (px < sel->ex)
 291                                 return (0);
 292
 293                         if (px > sel->sx)
 294                                 return (0);
 295                 } else {
 296                         /* Selection start (sx) is on the left. */
 297                         if (px < sel->sx)
 298                                 return (0);
 299
 300                         if (px > sel->ex)
 301                                 return (0);
 302                 }
 303         } else {
 304                 /*
 305                  * Like emacs, keep the top-left-most character, and drop the
 306                  * bottom-right-most, regardless of copy direction.
 307                  */
 308                 if (sel->sy < sel->ey) {
 309                         /* starting line < ending line -- downward selection. */
 310                         if (py < sel->sy || py > sel->ey)
 311                                 return (0);
 312
 313                         if ((py == sel->sy && px < sel->sx)
 314                             || (py == sel->ey && px > sel->ex))
 315                                 return (0);
 316                 } else if (sel->sy > sel->ey) {
 317                         /* starting line > ending line -- upward selection. */
 318                         if (py > sel->sy || py < sel->ey)
 319                                 return (0);
 320
 321                         if ((py == sel->sy && px >= sel->sx)
 322                             || (py == sel->ey && px < sel->ex))
 323                                 return (0);
 324                 } else {
 325                         /* starting line == ending line. */
 326                         if (py != sel->sy)
 327                                 return (0);
 328
 329                         if (sel->ex < sel->sx) {
 330                                 /* cursor (ex) is on the left */
 331                                 if (px > sel->sx || px < sel->ex)
 332                                         return (0);
 333                         } else {
 334                                 /* selection start (sx) is on the left */
 335                                 if (px < sel->sx || px > sel->ex)
 336                                         return (0);
 337                         }
 338                 }
 339         }
 340
 341         return (1);
 342 }