objects/drawin.c

   1 /*
   2  * drawin.c - drawin functions
   3  *
   4  * Copyright © 2008-2009 Julien Danjou <julien@danjou.info>
   5  * Copyright ©      2010 Uli Schlachter <psychon@znc.in>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  */
  22
  23 #include "screen.h"
  24 #include "drawin.h"
  25 #include "objects/client.h"
  26 #include "screen.h"
  27 #include "xwindow.h"
  28 #include "luaa.h"
  29 #include "ewmh.h"
  30 #include "systray.h"
  31 #include "common/xcursor.h"
  32 #include "common/xutil.h"
  33
  34 #include <cairo-xcb.h>
  35
  36 LUA_OBJECT_FUNCS(drawin_class, drawin_t, drawin)
  37
  38 /** Kick out systray windows.
  39  */
  40 static void
  41 drawin_systray_kickout(drawin_t *w)
  42 {
  43     if(globalconf.systray.parent == w)
  44     {
  45         /* Who! Check that we're not deleting a drawin with a systray, because it
  46          * may be its parent. If so, we reparent to root before, otherwise it will
  47          * hurt very much. */
  48         systray_cleanup();
  49         xcb_reparent_window(globalconf.connection,
  50                             globalconf.systray.window,
  51                             globalconf.screen->root,
  52                             -512, -512);
  53
  54         globalconf.systray.parent = NULL;
  55     }
  56 }
  57
  58 static void
  59 drawin_wipe(drawin_t *w)
  60 {
  61     /* The drawin must already be unmapped, else it
  62      * couldn't be garbage collected -> no unmap needed */
  63     p_delete(&w->cursor);
  64     if(w->surface)
  65     {
  66         /* Make sure that cairo knows that this surface can't be unused anymore.
  67          * This is needed since lua could still have a reference to it. */
  68         cairo_surface_finish(w->surface);
  69         cairo_surface_destroy(w->surface);
  70         w->surface = NULL;
  71     }
  72     if(w->window)
  73     {
  74         /* Activate BMA */
  75         client_ignore_enterleave_events();
  76         /* Make sure we don't accidentally kill the systray window */
  77         drawin_systray_kickout(w);
  78         xcb_destroy_window(globalconf.connection, w->window);
  79         /* Deactivate BMA */
  80         client_restore_enterleave_events();
  81         w->window = XCB_NONE;
  82     }
  83     if(w->pixmap)
  84     {
  85         xcb_free_pixmap(globalconf.connection, w->pixmap);
  86         w->pixmap = XCB_NONE;
  87     }
  88 }
  89
  90 void
  91 drawin_unref_simplified(drawin_t **item)
  92 {
  93     luaA_object_unref(globalconf.L, *item);
  94 }
  95
  96 static void
  97 drawin_update_drawing(drawin_t *w)
  98 {
  99     /* If this drawin isn't visible, we don't need an up-to-date cairo surface
 100      * for it. (drawin_map() will later make sure we are called again) */
 101     if(!w->visible)
 102         return;
 103     /* Clean up old stuff */
 104     if(w->surface)
 105     {
 106         /* In case lua still got a reference to the surface, it still won't be
 107          * able to do anything with it because we finish it. */
 108         cairo_surface_finish(w->surface);
 109         cairo_surface_destroy(w->surface);
 110     }
 111     if(w->pixmap)
 112         xcb_free_pixmap(globalconf.connection, w->pixmap);
 113
 114     /* Create a pixmap */
 115     xcb_screen_t *s = globalconf.screen;
 116     w->pixmap = xcb_generate_id(globalconf.connection);
 117     xcb_create_pixmap(globalconf.connection, globalconf.default_depth, w->pixmap, s->root,
 118                       w->geometry.width, w->geometry.height);
 119     /* and create a surface for that pixmap */
 120     w->surface = cairo_xcb_surface_create(globalconf.connection,
 121                                           w->pixmap, globalconf.visual,
 122                                           w->geometry.width, w->geometry.height);
 123     /* Make sure the pixmap doesn't contain garbage by filling it with black */
 124     cairo_t *cr = cairo_create(w->surface);
 125     cairo_set_operator(cr, CAIRO_OPERATOR_CLEAR);
 126     cairo_paint(cr);
 127     cairo_destroy(cr);
 128 }
 129
 130 /** Initialize a drawin.
 131  * \param w The drawin to initialize.
 132  */
 133 static void
 134 drawin_init(drawin_t *w)
 135 {
 136     xcb_screen_t *s = globalconf.screen;
 137
 138     w->window = xcb_generate_id(globalconf.connection);
 139     xcb_create_window(globalconf.connection, globalconf.default_depth, w->window, s->root,
 140                       w->geometry.x, w->geometry.y,
 141                       w->geometry.width, w->geometry.height,
 142                       w->border_width, XCB_COPY_FROM_PARENT, globalconf.visual->visual_id,
 143                       XCB_CW_BORDER_PIXEL | XCB_CW_BIT_GRAVITY
 144                       | XCB_CW_OVERRIDE_REDIRECT | XCB_CW_EVENT_MASK | XCB_CW_COLORMAP
 145                       | XCB_CW_CURSOR,
 146                       (const uint32_t [])
 147                       {
 148                           w->border_color.pixel,
 149                           XCB_GRAVITY_NORTH_WEST,
 150                           1,
 151                           XCB_EVENT_MASK_SUBSTRUCTURE_REDIRECT
 152                           | XCB_EVENT_MASK_SUBSTRUCTURE_NOTIFY | XCB_EVENT_MASK_ENTER_WINDOW
 153                           | XCB_EVENT_MASK_LEAVE_WINDOW | XCB_EVENT_MASK_STRUCTURE_NOTIFY
 154                           | XCB_EVENT_MASK_POINTER_MOTION | XCB_EVENT_MASK_EXPOSURE
 155                           | XCB_EVENT_MASK_PROPERTY_CHANGE,
 156                           globalconf.default_cmap,
 157                           xcursor_new(globalconf.connection, xcursor_font_fromstr(w->cursor))
 158                       });
 159
 160     /* Set the right properties */
 161     ewmh_update_window_type(w->window, window_translate_type(w->type));
 162     ewmh_update_strut(w->window, &w->strut);
 163 }
 164
 165 /** Refresh the window content by copying its pixmap data to its window.
 166  * \param w The drawin to refresh.
 167  */
 168 static inline void
 169 drawin_refresh_pixmap(drawin_t *w)
 170 {
 171     drawin_refresh_pixmap_partial(w, 0, 0, w->geometry.width, w->geometry.height);
 172 }
 173
 174 /** Move and/or resize a drawin
 175  * \param L The Lua VM state.
 176  * \param udx The index of the drawin.
 177  * \param geometry The new geometry.
 178  */
 179 static void
 180 drawin_moveresize(lua_State *L, int udx, area_t geometry)
 181 {
 182     drawin_t *w = luaA_checkudata(L, udx, &drawin_class);
 183     int number_of_vals = 0;
 184     uint32_t moveresize_win_vals[4], mask_vals = 0;
 185
 186     if(w->geometry.x != geometry.x)
 187     {
 188         w->geometry.x = moveresize_win_vals[number_of_vals++] = geometry.x;
 189         mask_vals |= XCB_CONFIG_WINDOW_X;
 190     }
 191
 192     if(w->geometry.y != geometry.y)
 193     {
 194         w->geometry.y = moveresize_win_vals[number_of_vals++] = geometry.y;
 195         mask_vals |= XCB_CONFIG_WINDOW_Y;
 196     }
 197
 198     if(geometry.width > 0 && w->geometry.width != geometry.width)
 199     {
 200         w->geometry.width = moveresize_win_vals[number_of_vals++] = geometry.width;
 201         mask_vals |= XCB_CONFIG_WINDOW_WIDTH;
 202     }
 203
 204     if(geometry.height > 0 && w->geometry.height != geometry.height)
 205     {
 206         w->geometry.height = moveresize_win_vals[number_of_vals++] = geometry.height;
 207         mask_vals |= XCB_CONFIG_WINDOW_HEIGHT;
 208     }
 209
 210     if(mask_vals & (XCB_CONFIG_WINDOW_WIDTH | XCB_CONFIG_WINDOW_HEIGHT))
 211         drawin_update_drawing(w);
 212
 213     /* Activate BMA */
 214     client_ignore_enterleave_events();
 215
 216     if(mask_vals)
 217         xcb_configure_window(globalconf.connection, w->window, mask_vals, moveresize_win_vals);
 218
 219     /* Deactivate BMA */
 220     client_restore_enterleave_events();
 221
 222     if(mask_vals & XCB_CONFIG_WINDOW_X)
 223         luaA_object_emit_signal(L, udx, "property::x", 0);
 224     if(mask_vals & XCB_CONFIG_WINDOW_Y)
 225         luaA_object_emit_signal(L, udx, "property::y", 0);
 226     if(mask_vals & XCB_CONFIG_WINDOW_WIDTH)
 227         luaA_object_emit_signal(L, udx, "property::width", 0);
 228     if(mask_vals & XCB_CONFIG_WINDOW_HEIGHT)
 229         luaA_object_emit_signal(L, udx, "property::height", 0);
 230 }
 231
 232 /** Refresh the window content by copying its pixmap data to its window.
 233  * \param drawin The drawin to refresh.
 234  * \param x The copy starting point x component.
 235  * \param y The copy starting point y component.
 236  * \param w The copy width from the x component.
 237  * \param h The copy height from the y component.
 238  */
 239 void
 240 drawin_refresh_pixmap_partial(drawin_t *drawin,
 241                               int16_t x, int16_t y,
 242                               uint16_t w, uint16_t h)
 243 {
 244     /* Make cairo do all pending drawing */
 245     cairo_surface_flush(drawin->surface);
 246     xcb_copy_area(globalconf.connection, drawin->pixmap,
 247                   drawin->window, globalconf.gc, x, y, x, y,
 248                   w, h);
 249 }
 250
 251 static void
 252 drawin_map(drawin_t *drawin)
 253 {
 254     /* Activate BMA */
 255     client_ignore_enterleave_events();
 256     /* Map the drawin */
 257     xcb_map_window(globalconf.connection, drawin->window);
 258     drawin_update_drawing(drawin);
 259     /* Deactivate BMA */
 260     client_restore_enterleave_events();
 261     /* Stack this drawin correctly */
 262     stack_windows();
 263     /* Add it to the list of visible drawins */
 264     drawin_array_append(&globalconf.drawins, drawin);
 265 }
 266
 267 static void
 268 drawin_unmap(drawin_t *drawin)
 269 {
 270     xcb_unmap_window(globalconf.connection, drawin->window);
 271     foreach(item, globalconf.drawins)
 272         if(*item == drawin)
 273         {
 274             drawin_array_remove(&globalconf.drawins, item);
 275             break;
 276         }
 277 }
 278
 279 /** Get a drawin by its window.
 280  * \param win The window id.
 281  * \return A drawin if found, NULL otherwise.
 282  */
 283 drawin_t *
 284 drawin_getbywin(xcb_window_t win)
 285 {
 286     foreach(w, globalconf.drawins)
 287         if((*w)->window == win)
 288             return *w;
 289     return NULL;
 290 }
 291
 292 /** Set a drawin visible or not.
 293  * \param L The Lua VM state.
 294  * \param udx The drawin.
 295  * \param v The visible value.
 296  */
 297 static void
 298 drawin_set_visible(lua_State *L, int udx, bool v)
 299 {
 300     drawin_t *drawin = luaA_checkudata(L, udx, &drawin_class);
 301     if(v != drawin->visible)
 302     {
 303         drawin->visible = v;
 304
 305         if(drawin->visible)
 306         {
 307             drawin_map(drawin);
 308             /* duplicate drawin */
 309             lua_pushvalue(L, udx);
 310             /* ref it */
 311             luaA_object_ref_class(globalconf.L, -1, &drawin_class);
 312         }
 313         else
 314         {
 315             /* Active BMA */
 316             client_ignore_enterleave_events();
 317             /* Unmap window */
 318             drawin_unmap(drawin);
 319             /* Active BMA */
 320             client_restore_enterleave_events();
 321             /* unref it */
 322             luaA_object_unref(globalconf.L, drawin);
 323         }
 324
 325         luaA_object_emit_signal(L, udx, "property::visible", 0);
 326         if(strut_has_value(&drawin->strut))
 327         {
 328             screen_t *screen =
 329                 screen_getbycoord(drawin->geometry.x, drawin->geometry.y);
 330             screen_emit_signal(globalconf.L, screen, "property::workarea", 0);
 331         }
 332     }
 333 }
 334
 335 static drawin_t *
 336 drawin_allocator(lua_State *L)
 337 {
 338     drawin_t *w = drawin_new(L);
 339
 340     w->visible = false;
 341
 342     w->opacity = -1;
 343     w->cursor = a_strdup("left_ptr");
 344     w->geometry.width = 1;
 345     w->geometry.height = 1;
 346     w->type = _NET_WM_WINDOW_TYPE_NORMAL;
 347
 348     drawin_init(w);
 349
 350     return w;
 351 }
 352
 353 /** Create a new drawin.
 354  * \param L The Lua VM state.
 355  * \return The number of elements pushed on stack.
 356  */
 357 static int
 358 luaA_drawin_new(lua_State *L)
 359 {
 360     luaA_class_new(L, &drawin_class);
 361
 362     return 1;
 363 }
 364
 365 /* Set or get the drawin geometry.
 366  * \param L The Lua VM state.
 367  * \return The number of elements pushed on stack.
 368  * \luastack
 369  * \lparam An optional table with drawin geometry.
 370  * \lreturn The drawin geometry.
 371  */
 372 static int
 373 luaA_drawin_geometry(lua_State *L)
 374 {
 375     drawin_t *drawin = luaA_checkudata(L, 1, &drawin_class);
 376
 377     if(lua_gettop(L) == 2)
 378     {
 379         area_t wingeom;
 380
 381         luaA_checktable(L, 2);
 382         wingeom.x = luaA_getopt_number(L, 2, "x", drawin->geometry.x);
 383         wingeom.y = luaA_getopt_number(L, 2, "y", drawin->geometry.y);
 384         wingeom.width = luaA_getopt_number(L, 2, "width", drawin->geometry.width);
 385         wingeom.height = luaA_getopt_number(L, 2, "height", drawin->geometry.height);
 386
 387         if(wingeom.width > 0 && wingeom.height > 0)
 388             drawin_moveresize(L, 1, wingeom);
 389     }
 390
 391     return luaA_pusharea(L, drawin->geometry);
 392 }
 393
 394
 395 LUA_OBJECT_EXPORT_PROPERTY(drawin, drawin_t, ontop, lua_pushboolean)
 396 LUA_OBJECT_EXPORT_PROPERTY(drawin, drawin_t, cursor, lua_pushstring)
 397 LUA_OBJECT_EXPORT_PROPERTY(drawin, drawin_t, visible, lua_pushboolean)
 398
 399 static int
 400 luaA_drawin_set_x(lua_State *L, drawin_t *drawin)
 401 {
 402     drawin_moveresize(L, -3, (area_t) { .x = luaL_checknumber(L, -1),
 403                                         .y = drawin->geometry.y,
 404                                         .width = drawin->geometry.width,
 405                                         .height = drawin->geometry.height });
 406     return 0;
 407 }
 408
 409 static int
 410 luaA_drawin_get_x(lua_State *L, drawin_t *drawin)
 411 {
 412     lua_pushnumber(L, drawin->geometry.x);
 413     return 1;
 414 }
 415
 416 static int
 417 luaA_drawin_set_y(lua_State *L, drawin_t *drawin)
 418 {
 419     drawin_moveresize(L, -3, (area_t) { .x = drawin->geometry.x,
 420                                         .y = luaL_checknumber(L, -1),
 421                                         .width = drawin->geometry.width,
 422                                         .height = drawin->geometry.height });
 423     return 0;
 424 }
 425
 426 static int
 427 luaA_drawin_get_y(lua_State *L, drawin_t *drawin)
 428 {
 429     lua_pushnumber(L, drawin->geometry.y);
 430     return 1;
 431 }
 432
 433 static int
 434 luaA_drawin_set_width(lua_State *L, drawin_t *drawin)
 435 {
 436     int width = luaL_checknumber(L, -1);
 437     if(width <= 0)
 438         luaL_error(L, "invalid width");
 439     drawin_moveresize(L, -3, (area_t) { .x = drawin->geometry.x,
 440                                         .y = drawin->geometry.y,
 441                                         .width = width,
 442                                         .height = drawin->geometry.height });
 443     return 0;
 444 }
 445
 446 static int
 447 luaA_drawin_get_width(lua_State *L, drawin_t *drawin)
 448 {
 449     lua_pushnumber(L, drawin->geometry.width);
 450     return 1;
 451 }
 452
 453 static int
 454 luaA_drawin_set_height(lua_State *L, drawin_t *drawin)
 455 {
 456     int height = luaL_checknumber(L, -1);
 457     if(height <= 0)
 458         luaL_error(L, "invalid height");
 459     drawin_moveresize(L, -3, (area_t) { .x = drawin->geometry.x,
 460                                        .y = drawin->geometry.y,
 461                                        .width = drawin->geometry.width,
 462                                        .height = height });
 463     return 0;
 464 }
 465
 466 static int
 467 luaA_drawin_get_height(lua_State *L, drawin_t *drawin)
 468 {
 469     lua_pushnumber(L, drawin->geometry.height);
 470     return 1;
 471 }
 472
 473 /** Set the drawin on top status.
 474  * \param L The Lua VM state.
 475  * \param drawin The drawin object.
 476  * \return The number of elements pushed on stack.
 477  */
 478 static int
 479 luaA_drawin_set_ontop(lua_State *L, drawin_t *drawin)
 480 {
 481     bool b = luaA_checkboolean(L, -1);
 482     if(b != drawin->ontop)
 483     {
 484         drawin->ontop = b;
 485         stack_windows();
 486         luaA_object_emit_signal(L, -3, "property::ontop", 0);
 487     }
 488     return 0;
 489 }
 490
 491 /** Set the drawin cursor.
 492  * \param L The Lua VM state.
 493  * \param drawin The drawin object.
 494  * \return The number of elements pushed on stack.
 495  */
 496 static int
 497 luaA_drawin_set_cursor(lua_State *L, drawin_t *drawin)
 498 {
 499     const char *buf = luaL_checkstring(L, -1);
 500     if(buf)
 501     {
 502         uint16_t cursor_font = xcursor_font_fromstr(buf);
 503         if(cursor_font)
 504         {
 505             xcb_cursor_t cursor = xcursor_new(globalconf.connection, cursor_font);
 506             p_delete(&drawin->cursor);
 507             drawin->cursor = a_strdup(buf);
 508             xwindow_set_cursor(drawin->window, cursor);
 509             luaA_object_emit_signal(L, -3, "property::cursor", 0);
 510         }
 511     }
 512     return 0;
 513 }
 514
 515 /** Set the drawin visibility.
 516  * \param L The Lua VM state.
 517  * \param drawin The drawin object.
 518  * \return The number of elements pushed on stack.
 519  */
 520 static int
 521 luaA_drawin_set_visible(lua_State *L, drawin_t *drawin)
 522 {
 523     drawin_set_visible(L, -3, luaA_checkboolean(L, -1));
 524     return 0;
 525 }
 526
 527 /** Get a drawin's surface
 528  * \param L The Lua VM state.
 529  * \param drawin The drawin object.
 530  * \return The number of elements pushed on stack.
 531  */
 532 static int
 533 luaA_drawin_get_surface(lua_State *L, drawin_t *drawin)
 534 {
 535     return oocairo_surface_push(L, drawin->surface);
 536 }
 537
 538 /** Refresh a drawin's content. This has to be called whenever some drawing to
 539  * the drawin's surface has been done and should become visible.
 540  * \param L The Lua VM state.
 541  * \return The number of elements pushed on stack.
 542  */
 543 static int
 544 luaA_drawin_refresh(lua_State *L)
 545 {
 546     drawin_t *drawin = luaA_checkudata(L, 1, &drawin_class);
 547     drawin_refresh_pixmap(drawin);
 548
 549     return 0;
 550 }
 551
 552 void
 553 drawin_class_setup(lua_State *L)
 554 {
 555     static const struct luaL_reg drawin_methods[] =
 556     {
 557         LUA_CLASS_METHODS(drawin)
 558         { "__call", luaA_drawin_new },
 559         { NULL, NULL }
 560     };
 561
 562     static const struct luaL_reg drawin_meta[] =
 563     {
 564         LUA_OBJECT_META(drawin)
 565         LUA_CLASS_META
 566         { "geometry", luaA_drawin_geometry },
 567         { "refresh", luaA_drawin_refresh },
 568         { NULL, NULL },
 569     };
 570
 571     luaA_class_setup(L, &drawin_class, "drawin", &window_class,
 572                      (lua_class_allocator_t) drawin_allocator,
 573                      (lua_class_collector_t) drawin_wipe,
 574                      NULL,
 575                      luaA_class_index_miss_property, luaA_class_newindex_miss_property,
 576                      drawin_methods, drawin_meta);
 577     luaA_class_add_property(&drawin_class, "surface",
 578                             NULL,
 579                             (lua_class_propfunc_t) luaA_drawin_get_surface,
 580                             NULL);
 581     luaA_class_add_property(&drawin_class, "visible",
 582                             (lua_class_propfunc_t) luaA_drawin_set_visible,
 583                             (lua_class_propfunc_t) luaA_drawin_get_visible,
 584                             (lua_class_propfunc_t) luaA_drawin_set_visible);
 585     luaA_class_add_property(&drawin_class, "ontop",
 586                             (lua_class_propfunc_t) luaA_drawin_set_ontop,
 587                             (lua_class_propfunc_t) luaA_drawin_get_ontop,
 588                             (lua_class_propfunc_t) luaA_drawin_set_ontop);
 589     luaA_class_add_property(&drawin_class, "cursor",
 590                             (lua_class_propfunc_t) luaA_drawin_set_cursor,
 591                             (lua_class_propfunc_t) luaA_drawin_get_cursor,
 592                             (lua_class_propfunc_t) luaA_drawin_set_cursor);
 593     luaA_class_add_property(&drawin_class, "x",
 594                             (lua_class_propfunc_t) luaA_drawin_set_x,
 595                             (lua_class_propfunc_t) luaA_drawin_get_x,
 596                             (lua_class_propfunc_t) luaA_drawin_set_x);
 597     luaA_class_add_property(&drawin_class, "y",
 598                             (lua_class_propfunc_t) luaA_drawin_set_y,
 599                             (lua_class_propfunc_t) luaA_drawin_get_y,
 600                             (lua_class_propfunc_t) luaA_drawin_set_y);
 601     luaA_class_add_property(&drawin_class, "width",
 602                             (lua_class_propfunc_t) luaA_drawin_set_width,
 603                             (lua_class_propfunc_t) luaA_drawin_get_width,
 604                             (lua_class_propfunc_t) luaA_drawin_set_width);
 605     luaA_class_add_property(&drawin_class, "height",
 606                             (lua_class_propfunc_t) luaA_drawin_set_height,
 607                             (lua_class_propfunc_t) luaA_drawin_get_height,
 608                             (lua_class_propfunc_t) luaA_drawin_set_height);
 609     luaA_class_add_property(&drawin_class, "type",
 610                             (lua_class_propfunc_t) luaA_window_set_type,
 611                             (lua_class_propfunc_t) luaA_window_get_type,
 612                             (lua_class_propfunc_t) luaA_window_set_type);
 613
 614     signal_add(&drawin_class.signals, "mouse::enter");
 615     signal_add(&drawin_class.signals, "mouse::leave");
 616     signal_add(&drawin_class.signals, "property::border_width");
 617     signal_add(&drawin_class.signals, "property::cursor");
 618     signal_add(&drawin_class.signals, "property::height");
 619     signal_add(&drawin_class.signals, "property::ontop");
 620     signal_add(&drawin_class.signals, "property::visible");
 621     signal_add(&drawin_class.signals, "property::widgets");
 622     signal_add(&drawin_class.signals, "property::width");
 623     signal_add(&drawin_class.signals, "property::x");
 624     signal_add(&drawin_class.signals, "property::y");
 625 }
 626
 627 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80