i3

src/xcb.c

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00001 /*
00002  * vim:ts=8:expandtab
00003  *
00004  * i3 - an improved dynamic tiling window manager
00005  *
00006  * © 2009-2010 Michael Stapelberg and contributors
00007  *
00008  * See file LICENSE for license information.
00009  *
00010  * xcb.c: Helper functions for easier usage of XCB
00011  *
00012  */
00013 #include <stdint.h>
00014 #include <stdio.h>
00015 #include <stdlib.h>
00016 #include <string.h>
00017 
00018 #include <xcb/xcb.h>
00019 #include <xcb/xcb_keysyms.h>
00020 
00021 #include "i3.h"
00022 #include "util.h"
00023 #include "xcb.h"
00024 #include "log.h"
00025 
00026 TAILQ_HEAD(cached_fonts_head, Font) cached_fonts = TAILQ_HEAD_INITIALIZER(cached_fonts);
00027 unsigned int xcb_numlock_mask;
00028 
00029 /*
00030  * Loads a font for usage, getting its height. This function is used very often, so it
00031  * maintains a cache.
00032  *
00033  */
00034 i3Font *load_font(xcb_connection_t *conn, const char *pattern) {
00035         /* Check if we got the font cached */
00036         i3Font *font;
00037         TAILQ_FOREACH(font, &cached_fonts, fonts)
00038                 if (strcmp(font->pattern, pattern) == 0)
00039                         return font;
00040 
00041         i3Font *new = smalloc(sizeof(i3Font));
00042         xcb_void_cookie_t font_cookie;
00043         xcb_list_fonts_with_info_cookie_t info_cookie;
00044 
00045         /* Send all our requests first */
00046         new->id = xcb_generate_id(conn);
00047         font_cookie = xcb_open_font_checked(conn, new->id, strlen(pattern), pattern);
00048         info_cookie = xcb_list_fonts_with_info(conn, 1, strlen(pattern), pattern);
00049 
00050         check_error(conn, font_cookie, "Could not open font");
00051 
00052         /* Get information (height/name) for this font */
00053         xcb_list_fonts_with_info_reply_t *reply = xcb_list_fonts_with_info_reply(conn, info_cookie, NULL);
00054         exit_if_null(reply, "Could not load font \"%s\"\n", pattern);
00055 
00056         if (asprintf(&(new->name), "%.*s", xcb_list_fonts_with_info_name_length(reply),
00057                                            xcb_list_fonts_with_info_name(reply)) == -1)
00058                 die("asprintf() failed\n");
00059         new->pattern = sstrdup(pattern);
00060         new->height = reply->font_ascent + reply->font_descent;
00061 
00062         /* Insert into cache */
00063         TAILQ_INSERT_TAIL(&cached_fonts, new, fonts);
00064 
00065         return new;
00066 }
00067 
00068 /*
00069  * Returns the colorpixel to use for the given hex color (think of HTML).
00070  *
00071  * The hex_color has to start with #, for example #FF00FF.
00072  *
00073  * NOTE that get_colorpixel() does _NOT_ check the given color code for validity.
00074  * This has to be done by the caller.
00075  *
00076  */
00077 uint32_t get_colorpixel(xcb_connection_t *conn, char *hex) {
00078         char strgroups[3][3] = {{hex[1], hex[2], '\0'},
00079                                 {hex[3], hex[4], '\0'},
00080                                 {hex[5], hex[6], '\0'}};
00081         uint32_t rgb16[3] = {(strtol(strgroups[0], NULL, 16)),
00082                              (strtol(strgroups[1], NULL, 16)),
00083                              (strtol(strgroups[2], NULL, 16))};
00084 
00085         return (rgb16[0] << 16) + (rgb16[1] << 8) + rgb16[2];
00086 }
00087 
00088 /*
00089  * Convenience wrapper around xcb_create_window which takes care of depth, generating an ID and checking
00090  * for errors.
00091  *
00092  */
00093 xcb_window_t create_window(xcb_connection_t *conn, Rect dims, uint16_t window_class, int cursor,
00094                            bool map, uint32_t mask, uint32_t *values) {
00095         xcb_window_t result = xcb_generate_id(conn);
00096         xcb_cursor_t cursor_id = xcb_generate_id(conn);
00097 
00098         /* If the window class is XCB_WINDOW_CLASS_INPUT_ONLY, depth has to be 0 */
00099         uint16_t depth = (window_class == XCB_WINDOW_CLASS_INPUT_ONLY ? 0 : XCB_COPY_FROM_PARENT);
00100 
00101         xcb_create_window(conn,
00102                           depth,
00103                           result, /* the window id */
00104                           root, /* parent == root */
00105                           dims.x, dims.y, dims.width, dims.height, /* dimensions */
00106                           0, /* border = 0, we draw our own */
00107                           window_class,
00108                           XCB_WINDOW_CLASS_COPY_FROM_PARENT, /* copy visual from parent */
00109                           mask,
00110                           values);
00111 
00112         /* Set the cursor */
00113         i3Font *cursor_font = load_font(conn, "cursor");
00114         xcb_create_glyph_cursor(conn, cursor_id, cursor_font->id, cursor_font->id,
00115                         (cursor == -1 ? XCB_CURSOR_LEFT_PTR : cursor),
00116                         (cursor == -1 ? XCB_CURSOR_LEFT_PTR : cursor) + 1,
00117                         0, 0, 0, 65535, 65535, 65535);
00118         xcb_change_window_attributes(conn, result, XCB_CW_CURSOR, &cursor_id);
00119         xcb_free_cursor(conn, cursor_id);
00120 
00121         /* Map the window (= make it visible) */
00122         if (map)
00123                 xcb_map_window(conn, result);
00124 
00125         return result;
00126 }
00127 
00128 /*
00129  * Changes a single value in the graphic context (so one doesn’t have to define an array of values)
00130  *
00131  */
00132 void xcb_change_gc_single(xcb_connection_t *conn, xcb_gcontext_t gc, uint32_t mask, uint32_t value) {
00133         xcb_change_gc(conn, gc, mask, &value);
00134 }
00135 
00136 /*
00137  * Draws a line from x,y to to_x,to_y using the given color
00138  *
00139  */
00140 void xcb_draw_line(xcb_connection_t *conn, xcb_drawable_t drawable, xcb_gcontext_t gc,
00141                    uint32_t colorpixel, uint32_t x, uint32_t y, uint32_t to_x, uint32_t to_y) {
00142         xcb_change_gc_single(conn, gc, XCB_GC_FOREGROUND, colorpixel);
00143         xcb_point_t points[] = {{x, y}, {to_x, to_y}};
00144         xcb_poly_line(conn, XCB_COORD_MODE_ORIGIN, drawable, gc, 2, points);
00145 }
00146 
00147 /*
00148  * Draws a rectangle from x,y with width,height using the given color
00149  *
00150  */
00151 void xcb_draw_rect(xcb_connection_t *conn, xcb_drawable_t drawable, xcb_gcontext_t gc,
00152                    uint32_t colorpixel, uint32_t x, uint32_t y, uint32_t width, uint32_t height) {
00153         xcb_change_gc_single(conn, gc, XCB_GC_FOREGROUND, colorpixel);
00154         xcb_rectangle_t rect = {x, y, width, height};
00155         xcb_poly_fill_rectangle(conn, drawable, gc, 1, &rect);
00156 }
00157 
00158 /*
00159  * Generates a configure_notify event and sends it to the given window
00160  * Applications need this to think they’ve configured themselves correctly.
00161  * The truth is, however, that we will manage them.
00162  *
00163  */
00164 void fake_configure_notify(xcb_connection_t *conn, Rect r, xcb_window_t window) {
00165         xcb_configure_notify_event_t generated_event;
00166 
00167         generated_event.event = window;
00168         generated_event.window = window;
00169         generated_event.response_type = XCB_CONFIGURE_NOTIFY;
00170 
00171         generated_event.x = r.x;
00172         generated_event.y = r.y;
00173         generated_event.width = r.width;
00174         generated_event.height = r.height;
00175 
00176         generated_event.border_width = 0;
00177         generated_event.above_sibling = XCB_NONE;
00178         generated_event.override_redirect = false;
00179 
00180         xcb_send_event(conn, false, window, XCB_EVENT_MASK_STRUCTURE_NOTIFY, (char*)&generated_event);
00181         xcb_flush(conn);
00182 }
00183 
00184 /*
00185  * Generates a configure_notify_event with absolute coordinates (relative to the X root
00186  * window, not to the client’s frame) for the given client.
00187  *
00188  */
00189 void fake_absolute_configure_notify(xcb_connection_t *conn, Client *client) {
00190         Rect absolute;
00191 
00192         absolute.x = client->rect.x + client->child_rect.x;
00193         absolute.y = client->rect.y + client->child_rect.y;
00194         absolute.width = client->child_rect.width;
00195         absolute.height = client->child_rect.height;
00196 
00197         fake_configure_notify(conn, absolute, client->child);
00198 }
00199 
00200 /*
00201  * Finds out which modifier mask is the one for numlock, as the user may change this.
00202  *
00203  */
00204 void xcb_get_numlock_mask(xcb_connection_t *conn) {
00205         xcb_key_symbols_t *keysyms;
00206         xcb_get_modifier_mapping_cookie_t cookie;
00207         xcb_get_modifier_mapping_reply_t *reply;
00208         xcb_keycode_t *modmap;
00209         int mask, i;
00210         const int masks[8] = { XCB_MOD_MASK_SHIFT,
00211                                XCB_MOD_MASK_LOCK,
00212                                XCB_MOD_MASK_CONTROL,
00213                                XCB_MOD_MASK_1,
00214                                XCB_MOD_MASK_2,
00215                                XCB_MOD_MASK_3,
00216                                XCB_MOD_MASK_4,
00217                                XCB_MOD_MASK_5 };
00218 
00219         /* Request the modifier map */
00220         cookie = xcb_get_modifier_mapping_unchecked(conn);
00221 
00222         /* Get the keysymbols */
00223         keysyms = xcb_key_symbols_alloc(conn);
00224 
00225         if ((reply = xcb_get_modifier_mapping_reply(conn, cookie, NULL)) == NULL) {
00226                 xcb_key_symbols_free(keysyms);
00227                 return;
00228         }
00229 
00230         modmap = xcb_get_modifier_mapping_keycodes(reply);
00231 
00232         /* Get the keycode for numlock */
00233 #ifdef OLD_XCB_KEYSYMS_API
00234         xcb_keycode_t numlock = xcb_key_symbols_get_keycode(keysyms, XCB_NUM_LOCK);
00235 #else
00236         /* For now, we only use the first keysymbol. */
00237         xcb_keycode_t *numlock_syms = xcb_key_symbols_get_keycode(keysyms, XCB_NUM_LOCK);
00238         if (numlock_syms == NULL)
00239                 return;
00240         xcb_keycode_t numlock = *numlock_syms;
00241         free(numlock_syms);
00242 #endif
00243 
00244         /* Check all modifiers (Mod1-Mod5, Shift, Control, Lock) */
00245         for (mask = 0; mask < 8; mask++)
00246                 for (i = 0; i < reply->keycodes_per_modifier; i++)
00247                         if (modmap[(mask * reply->keycodes_per_modifier) + i] == numlock)
00248                                 xcb_numlock_mask = masks[mask];
00249 
00250         xcb_key_symbols_free(keysyms);
00251         free(reply);
00252 }
00253 
00254 /*
00255  * Raises the given window (typically client->frame) above all other windows
00256  *
00257  */
00258 void xcb_raise_window(xcb_connection_t *conn, xcb_window_t window) {
00259         uint32_t values[] = { XCB_STACK_MODE_ABOVE };
00260         xcb_configure_window(conn, window, XCB_CONFIG_WINDOW_STACK_MODE, values);
00261 }
00262 
00263 /*
00264  *
00265  * Prepares the given Cached_Pixmap for usage (checks whether the size of the
00266  * object this pixmap is related to (e.g. a window) has changed and re-creates
00267  * the pixmap if so).
00268  *
00269  */
00270 void cached_pixmap_prepare(xcb_connection_t *conn, struct Cached_Pixmap *pixmap) {
00271         DLOG("preparing pixmap\n");
00272 
00273         /* If the Rect did not change, the pixmap does not need to be recreated */
00274         if (memcmp(&(pixmap->rect), pixmap->referred_rect, sizeof(Rect)) == 0)
00275                 return;
00276 
00277         memcpy(&(pixmap->rect), pixmap->referred_rect, sizeof(Rect));
00278 
00279         if (pixmap->id == 0 || pixmap->gc == 0) {
00280                 DLOG("Creating new pixmap...\n");
00281                 pixmap->id = xcb_generate_id(conn);
00282                 pixmap->gc = xcb_generate_id(conn);
00283         } else {
00284                 DLOG("Re-creating this pixmap...\n");
00285                 xcb_free_gc(conn, pixmap->gc);
00286                 xcb_free_pixmap(conn, pixmap->id);
00287         }
00288 
00289         xcb_create_pixmap(conn, root_depth, pixmap->id,
00290                           pixmap->referred_drawable, pixmap->rect.width, pixmap->rect.height);
00291 
00292         xcb_create_gc(conn, pixmap->gc, pixmap->id, 0, 0);
00293 }
00294 
00295 /*
00296  * Query the width of the given text (16-bit characters, UCS) with given real
00297  * length (amount of glyphs) using the given font.
00298  *
00299  */
00300 int predict_text_width(xcb_connection_t *conn, const char *font_pattern, char *text, int length) {
00301         i3Font *font = load_font(conn, font_pattern);
00302 
00303         xcb_query_text_extents_cookie_t cookie;
00304         xcb_query_text_extents_reply_t *reply;
00305         xcb_generic_error_t *error;
00306         int width;
00307 
00308         cookie = xcb_query_text_extents(conn, font->id, length, (xcb_char2b_t*)text);
00309         if ((reply = xcb_query_text_extents_reply(conn, cookie, &error)) == NULL) {
00310                 ELOG("Could not get text extents (X error code %d)\n",
00311                      error->error_code);
00312                 /* We return the rather safe guess of 7 pixels, because a
00313                  * rendering error is better than a crash. Plus, the user will
00314                  * see the error in his log. */
00315                 return 7;
00316         }
00317 
00318         width = reply->overall_width;
00319         free(reply);
00320         return width;
00321 }
00322 
00323 /*
00324  * Configures the given window to have the size/position specified by given rect
00325  *
00326  */
00327 void xcb_set_window_rect(xcb_connection_t *conn, xcb_window_t window, Rect r) {
00328         xcb_configure_window(conn, window,
00329                              XCB_CONFIG_WINDOW_X |
00330                              XCB_CONFIG_WINDOW_Y |
00331                              XCB_CONFIG_WINDOW_WIDTH |
00332                              XCB_CONFIG_WINDOW_HEIGHT,
00333                              &(r.x));
00334 }