i3 - improved tiling WM

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Add optional bidirectional interface to i3bar. (ver.3)

Patch status: superseded

Patch by enkore

Long description:

If the child specifies bidirectional:1 in the protocl header,
a JSON array will be streamed to it's stdin.
It consists of maps with at least one key (command).

Such a map is emitted if the user clicks on a status block. i.e.
{"command":"block_clicked","name":"some_block_name","instance":"optional_instance"}

The basic output format is like the rest of the i3bar protocol (i.e.
a new line after each element (map in this case))

The second version of this patch mainly introduced a better API for sending
commands.

The third version of this patch introduced the additional button parameter and thus
added support for right clicks. Now root window coordinates are passed instead of
window coordinates.

To apply this patch, use:
curl http://cr.i3wm.org/patch/72/raw.patch | git am

b/docs/i3bar-protocol

@@ -51,7 +51,7 @@ consists of a single JSON hash:
 
 *All features example*:
 ------------------------------
-{ "version": 1, "stop_signal": 10, "cont_signal": 12 }
+{ "version": 1, "stop_signal": 10, "cont_signal": 12, "bidirectional": 1 }
 ------------------------------
 
 (Note that before i3 v4.3 the precise format had to be +{"version":1}+,
@@ -110,6 +110,9 @@ cont_signal::
 	Specify to i3bar the signal (as an integer)to send to continue your
 	processing.
 	The default value (if none is specified) is SIGCONT.
+bidirectional::
+	If specified and 1 i3bar will write a infinite array (same as above)
+	to your stdin.
 
 === Blocks in detail
 
@@ -183,3 +186,33 @@ An example of a block which uses all possible entries follows:
  "instance": "eth0"
 }
 ------------------------------------------
+
+=== Bidirectional communication
+
+If enabled i3bar will send you notifications about certain events, currently
+only one such notification is implmented: block_clicked.
+It is send if the user clicks on a block and looks like this:
+
+command::
+	Always block_clicked at the moment, but more are maybe added later.
+name::
+	Name of the block, if set
+instance::
+	Instance of the block, if set
+x, y::
+	X11 root window coordinates where the click occured
+button:
+	X11 button ID, either 1 or 3 for left or right mouse button,
+	respectively.
+
+*Example*:
+------------------------------------------
+{
+ "command": "block_clicked",
+ "name": "ethernet",
+ "instance": "eth0",
+ "button": 1,
+ "x": 1320,
+ "y": 1400
+}
+------------------------------------------

b/i3bar/include/child.h

@@ -33,6 +33,12 @@ typedef struct {
      * The signal requested by the client to inform it of theun hidden state of i3bar
      */
     int cont_signal;
+
+    /**
+     * Enable bi-directional communication, i.e. on-click events
+     */
+    bool bidirectional;
+    int bidirectional_init;
 } i3bar_child;
 
 /*
@@ -68,4 +74,10 @@ void stop_child(void);
  */
 void cont_child(void);
 
+/*
+ * ends the block_clicked command to the child
+ *
+ */
+void send_block_clicked(int button, const char *name, const char *instance, int x, int y);
+
 #endif

b/i3bar/include/common.h

@@ -50,6 +50,10 @@ struct status_block {
     uint32_t x_offset;
     uint32_t x_append;
 
+    /* Optional */
+    char *name;
+    char *instance;
+
     TAILQ_ENTRY(status_block) blocks;
 };
 

b/i3bar/src/child.c

@@ -21,6 +21,7 @@
 #include <yajl/yajl_common.h>
 #include <yajl/yajl_parse.h>
 #include <yajl/yajl_version.h>
+#include <yajl/yajl_gen.h>
 
 #include "common.h"
 
@@ -35,6 +36,9 @@ ev_child *child_sig;
 yajl_callbacks callbacks;
 yajl_handle parser;
 
+/* JSON generator for stdout */
+yajl_gen gen;
+
 typedef struct parser_ctx {
     /* True if one of the parsed blocks was urgent */
     bool has_urgent;
@@ -141,6 +145,18 @@ static int stdin_string(void *context, const unsigned char *val, unsigned int le
             ctx->block.align = ALIGN_CENTER;
         }
     }
+    if (strcasecmp(ctx->last_map_key, "name") == 0) {
+        char *copy = (char*)malloc(len+1);
+        strncpy(copy, (const char *)val, len);
+        copy[len] = 0;
+        ctx->block.name = copy;
+    }
+    if (strcasecmp(ctx->last_map_key, "instance") == 0) {
+        char *copy = (char*)malloc(len+1);
+        strncpy(copy, (const char *)val, len);
+        copy[len] = 0;
+        ctx->block.instance = copy;
+    }
     return 1;
 }
 
@@ -322,6 +338,18 @@ void child_sig_cb(struct ev_loop *loop, ev_child *watcher, int revents) {
     cleanup();
 }
 
+void child_write_output(void) {
+    if(child.bidirectional) {
+        const unsigned char *output;
+        size_t size;
+        yajl_gen_get_buf(gen, &output, &size);
+        fwrite(output, 1, size, stdout);
+        fwrite("\n", 1, 1, stdout);
+        fflush(stdout);
+        yajl_gen_clear(gen);    
+    }
+}
+
 /*
  * Start a child-process with the specified command and reroute stdin.
  * We actually start a $SHELL to execute the command so we don't have to care
@@ -347,10 +375,14 @@ void start_child(char *command) {
     parser = yajl_alloc(&callbacks, NULL, &parser_context);
 #endif
 
+    gen = yajl_gen_alloc(NULL);
+
     if (command != NULL) {
-        int fd[2];
+        int fd[4];
         if (pipe(fd) == -1)
             err(EXIT_FAILURE, "pipe(fd)");
+        if (pipe(&fd[2]) == -1)
+            err(EXIT_FAILURE, "pipe(fd)");
 
         child.pid = fork();
         switch (child.pid) {
@@ -358,10 +390,10 @@ void start_child(char *command) {
                 ELOG("Couldn't fork(): %s\n", strerror(errno));
                 exit(EXIT_FAILURE);
             case 0:
-                /* Child-process. Reroute stdout and start shell */
-                close(fd[0]);
+                /* Child-process. Reroute streams and start shell */
 
                 dup2(fd[1], STDOUT_FILENO);
+                dup2(fd[2], STDIN_FILENO);
 
                 static const char *shell = NULL;
 
@@ -371,9 +403,9 @@ void start_child(char *command) {
                 execl(shell, shell, "-c", command, (char*) NULL);
                 return;
             default:
-                /* Parent-process. Rerout stdin */
-                close(fd[1]);
+                /* Parent-process. Reroute streams */
 
+                dup2(fd[3], STDOUT_FILENO);
                 dup2(fd[0], STDIN_FILENO);
 
                 break;
@@ -396,6 +428,69 @@ void start_child(char *command) {
 }
 
 /*
+ * Internal helper functions for bidirectional comms
+ *
+ */
+void child_bidi_initialize(void) {
+    if(!child.bidirectional_init) {
+        yajl_gen_array_open(gen);
+        child_write_output();
+        child.bidirectional_init = 1;
+    }    
+}
+
+void child_bidi_key(const char *key) {
+    yajl_gen_string(gen, (const unsigned char *)key, strlen(key));
+}
+
+void child_bidi_open(const char *command) {
+    child_bidi_initialize();
+
+    yajl_gen_map_open(gen);
+
+    child_bidi_key("command");
+    yajl_gen_string(gen, (const unsigned char *)command, strlen(command));
+}
+
+void child_bidi_close(void) {
+    yajl_gen_map_close(gen);
+    child_write_output();
+}
+
+/*
+ * sends the block_clicked command to the child
+ *
+ */
+void send_block_clicked(int button, const char *name, const char *instance, int x, int y) {
+    if(child.bidirectional) {
+        child_bidi_open("block_clicked");
+
+        if(name) {
+            child_bidi_key("name");
+            yajl_gen_string(gen, (const unsigned char *)name, strlen(name));
+        }
+
+        if(instance) {
+            child_bidi_key("instance");
+            yajl_gen_string(gen, (const unsigned char *)instance, strlen(instance));
+        }
+
+        child_bidi_key("button");
+        yajl_gen_integer(gen, button);
+
+        child_bidi_key("x");
+        yajl_gen_integer(gen, x);
+
+        child_bidi_key("y");
+        yajl_gen_integer(gen, y);
+
+        yajl_gen_map_close(gen);
+
+        child_write_output();
+    }
+}
+
+/*
  * kill()s the child-process (if any). Called when exit()ing.
  *
  */

b/i3bar/src/parse_json_header.c

@@ -31,6 +31,7 @@ static enum {
     KEY_VERSION,
     KEY_STOP_SIGNAL,
     KEY_CONT_SIGNAL,
+    KEY_BIDIRECTIONAL,
     NO_KEY
 } current_key;
 
@@ -51,6 +52,8 @@ static int header_integer(void *ctx, long val) {
         case KEY_CONT_SIGNAL:
             child->cont_signal = val;
             break;
+        case KEY_BIDIRECTIONAL:
+            child->bidirectional = val;
         default:
             break;
     }
@@ -71,6 +74,8 @@ static int header_map_key(void *ctx, const unsigned char *stringval, unsigned in
         current_key = KEY_STOP_SIGNAL;
     } else if (CHECK_KEY("cont_signal")) {
         current_key = KEY_CONT_SIGNAL;
+    } else if (CHECK_KEY("bidirectional")) {
+        current_key = KEY_BIDIRECTIONAL;
     }
     return 1;
 }

b/i3bar/src/xcb.c

@@ -160,7 +160,7 @@ void refresh_statusline(void) {
     xcb_poly_fill_rectangle(xcb_connection, statusline_pm, statusline_clear, 1, &rect);
 
     /* Draw the text of each block. */
-    uint32_t x = 0;
+    uint32_t x = 0; 
     TAILQ_FOREACH(block, &statusline_head, blocks) {
         if (i3string_get_num_bytes(block->full_text) == 0)
             continue;
@@ -306,12 +306,14 @@ void handle_button(xcb_button_press_event_t *event) {
     }
 
     int32_t x = event->event_x >= 0 ? event->event_x : 0;
+    int32_t original_x = x;
 
     DLOG("Got Button %d\n", event->detail);
 
     switch (event->detail) {
         case 1:
-            /* Left Mousbutton. We determine, which button was clicked
+        case 3:
+            /* Left or right Mousbutton. We determine, which button was clicked
              * and set cur_ws accordingly */
             TAILQ_FOREACH(cur_ws, walk->workspaces, tailq) {
                 DLOG("x = %d\n", x);
@@ -321,8 +323,43 @@ void handle_button(xcb_button_press_event_t *event) {
                 x -= cur_ws->name_width + 11;
             }
             if (cur_ws == NULL) {
+                /* No workspace button was pressed.
+                 * Check if a status block has been clicked.
+                 * This of course only has an effect,
+                 * if the child reported bidirectional protocol usage. */
+
+                /* First calculate width of tray area */
+                trayclient *trayclient;
+                int tray_width = 0;
+                TAILQ_FOREACH_REVERSE(trayclient, walk->trayclients, tc_head, tailq) {
+                    if (!trayclient->mapped)
+                        continue;
+                    tray_width += (font.height + 2);
+                }
+
+                int block_x = 0, last_block_x;
+                int offset = (walk->rect.w - (statusline_width + tray_width)) - 10;
+                
+                x = original_x - offset > 0 ? original_x - offset : 0;
+
+                struct status_block *block;
+
+                TAILQ_FOREACH(block, &statusline_head, blocks) {
+                    last_block_x = block_x;
+                    block_x += block->width + block->x_offset + block->x_append;
+
+                    if(x <= block_x && x >= last_block_x) {
+                        send_block_clicked(event->detail, block->name, block->instance, event->root_x, event->root_y);
+                        return;
+                    }
+                }
                 return;
             }
+            if (event->detail == 3)
+                /* Don't actually switch the
+                 * workspace if it was the right mouse button
+                 */
+                return;
             break;
         case 4:
             /* Mouse wheel up. We select the previous ws, if any.

119	@@ -50,6 +50,10 @@ struct status_block {
120	uint32_t x_offset;
121	uint32_t x_append;
122
123	+ /* Optional */
124	+ char *name;
125	+ char *instance;
126	+
127	TAILQ_ENTRY(status_block) blocks;
128	};
129

134	@@ -21,6 +21,7 @@
135	#include <yajl/yajl_common.h>
136	#include <yajl/yajl_parse.h>
137	#include <yajl/yajl_version.h>
138	+#include <yajl/yajl_gen.h>
139
140	#include "common.h"
141
142	@@ -35,6 +36,9 @@ ev_child *child_sig;
143	yajl_callbacks callbacks;
144	yajl_handle parser;
145
146	+/* JSON generator for stdout */
147	+yajl_gen gen;
148	+
149	typedef struct parser_ctx {
150	/* True if one of the parsed blocks was urgent */
151	bool has_urgent;
152	@@ -141,6 +145,18 @@ static int stdin_string(void context, const unsigned char val, unsigned int le
153	ctx->block.align = ALIGN_CENTER;
154	}
155	}
156	+ if (strcasecmp(ctx->last_map_key, "name") == 0) {
157	+ char copy = (char)malloc(len+1);
158	+ strncpy(copy, (const char *)val, len);
159	+ copy[len] = 0;
160	+ ctx->block.name = copy;
161	+ }
162	+ if (strcasecmp(ctx->last_map_key, "instance") == 0) {
163	+ char copy = (char)malloc(len+1);
164	+ strncpy(copy, (const char *)val, len);
165	+ copy[len] = 0;
166	+ ctx->block.instance = copy;
167	+ }
168	return 1;
169	}
170
171	@@ -322,6 +338,18 @@ void child_sig_cb(struct ev_loop loop, ev_child watcher, int revents) {
172	cleanup();
173	}
174
175	+void child_write_output(void) {
176	+ if(child.bidirectional) {
177	+ const unsigned char *output;
178	+ size_t size;
179	+ yajl_gen_get_buf(gen, &output, &size);
180	+ fwrite(output, 1, size, stdout);
181	+ fwrite("\n", 1, 1, stdout);
182	+ fflush(stdout);
183	+ yajl_gen_clear(gen);
184	+ }
185	+}
186	+
187	/*
188	* Start a child-process with the specified command and reroute stdin.
189	* We actually start a $SHELL to execute the command so we don't have to care
190	@@ -347,10 +375,14 @@ void start_child(char *command) {
191	parser = yajl_alloc(&callbacks, NULL, &parser_context);
192	#endif
193
194	+ gen = yajl_gen_alloc(NULL);
195	+
196	if (command != NULL) {
197	- int fd[2];
198	+ int fd[4];
199	if (pipe(fd) == -1)
200	err(EXIT_FAILURE, "pipe(fd)");
201	+ if (pipe(&fd[2]) == -1)
202	+ err(EXIT_FAILURE, "pipe(fd)");
203
204	child.pid = fork();
205	switch (child.pid) {
206	@@ -358,10 +390,10 @@ void start_child(char *command) {
207	ELOG("Couldn't fork(): %s\n", strerror(errno));
208	exit(EXIT_FAILURE);
209	case 0:
210	- /* Child-process. Reroute stdout and start shell */
211	- close(fd[0]);
212	+ /* Child-process. Reroute streams and start shell */
213
214	dup2(fd[1], STDOUT_FILENO);
215	+ dup2(fd[2], STDIN_FILENO);
216
217	static const char *shell = NULL;
218
219	@@ -371,9 +403,9 @@ void start_child(char *command) {
220	execl(shell, shell, "-c", command, (char*) NULL);
221	return;
222	default:
223	- /* Parent-process. Rerout stdin */
224	- close(fd[1]);
225	+ /* Parent-process. Reroute streams */
226
227	+ dup2(fd[3], STDOUT_FILENO);
228	dup2(fd[0], STDIN_FILENO);
229
230	break;
231	@@ -396,6 +428,69 @@ void start_child(char *command) {
232	}
233
234	/*
235	+ * Internal helper functions for bidirectional comms
236	+ *
237	+ */
238	+void child_bidi_initialize(void) {
239	+ if(!child.bidirectional_init) {
240	+ yajl_gen_array_open(gen);
241	+ child_write_output();
242	+ child.bidirectional_init = 1;
243	+ }
244	+}
245	+
246	+void child_bidi_key(const char *key) {
247	+ yajl_gen_string(gen, (const unsigned char *)key, strlen(key));
248	+}
249	+
250	+void child_bidi_open(const char *command) {
251	+ child_bidi_initialize();
252	+
253	+ yajl_gen_map_open(gen);
254	+
255	+ child_bidi_key("command");
256	+ yajl_gen_string(gen, (const unsigned char *)command, strlen(command));
257	+}
258	+
259	+void child_bidi_close(void) {
260	+ yajl_gen_map_close(gen);
261	+ child_write_output();
262	+}
263	+
264	+/*
265	+ * sends the block_clicked command to the child
266	+ *
267	+ */
268	+void send_block_clicked(int button, const char name, const char instance, int x, int y) {
269	+ if(child.bidirectional) {
270	+ child_bidi_open("block_clicked");
271	+
272	+ if(name) {
273	+ child_bidi_key("name");
274	+ yajl_gen_string(gen, (const unsigned char *)name, strlen(name));
275	+ }
276	+
277	+ if(instance) {
278	+ child_bidi_key("instance");
279	+ yajl_gen_string(gen, (const unsigned char *)instance, strlen(instance));
280	+ }
281	+
282	+ child_bidi_key("button");
283	+ yajl_gen_integer(gen, button);
284	+
285	+ child_bidi_key("x");
286	+ yajl_gen_integer(gen, x);
287	+
288	+ child_bidi_key("y");
289	+ yajl_gen_integer(gen, y);
290	+
291	+ yajl_gen_map_close(gen);
292	+
293	+ child_write_output();
294	+ }
295	+}
296	+
297	+/*
298	* kill()s the child-process (if any). Called when exit()ing.
299	*
300	*/

34	@@ -51,7 +51,7 @@ consists of a single JSON hash:
35
36	All features example:
37	------------------------------
38	-{ "version": 1, "stop_signal": 10, "cont_signal": 12 }
39	+{ "version": 1, "stop_signal": 10, "cont_signal": 12, "bidirectional": 1 }
40	------------------------------
41
42	(Note that before i3 v4.3 the precise format had to be +{"version":1}+,
43	@@ -110,6 +110,9 @@ cont_signal::
44	Specify to i3bar the signal (as an integer)to send to continue your
45	processing.
46	The default value (if none is specified) is SIGCONT.
47	+bidirectional::
48	+ If specified and 1 i3bar will write a infinite array (same as above)
49	+ to your stdin.
50
51	=== Blocks in detail
52
53	@@ -183,3 +186,33 @@ An example of a block which uses all possible entries follows:
54	"instance": "eth0"
55	}
56	------------------------------------------
57	+
58	+=== Bidirectional communication
59	+
60	+If enabled i3bar will send you notifications about certain events, currently
61	+only one such notification is implmented: block_clicked.
62	+It is send if the user clicks on a block and looks like this:
63	+
64	+command::
65	+ Always block_clicked at the moment, but more are maybe added later.
66	+name::
67	+ Name of the block, if set
68	+instance::
69	+ Instance of the block, if set
70	+x, y::
71	+ X11 root window coordinates where the click occured
72	+button:
73	+ X11 button ID, either 1 or 3 for left or right mouse button,
74	+ respectively.
75	+
76	+Example:
77	+------------------------------------------
78	+{
79	+ "command": "block_clicked",
80	+ "name": "ethernet",
81	+ "instance": "eth0",
82	+ "button": 1,
83	+ "x": 1320,
84	+ "y": 1400
85	+}
86	+------------------------------------------

91	@@ -33,6 +33,12 @@ typedef struct {
92	* The signal requested by the client to inform it of theun hidden state of i3bar
93	*/
94	int cont_signal;
95	+
96	+ /**
97	+ * Enable bi-directional communication, i.e. on-click events
98	+ */
99	+ bool bidirectional;
100	+ int bidirectional_init;
101	} i3bar_child;
102
103	/*
104	@@ -68,4 +74,10 @@ void stop_child(void);
105	*/
106	void cont_child(void);
107
108	+/*
109	+ * ends the block_clicked command to the child
110	+ *
111	+ */
112	+void send_block_clicked(int button, const char name, const char instance, int x, int y);
113	+
114	#endif

305	@@ -31,6 +31,7 @@ static enum {
306	KEY_VERSION,
307	KEY_STOP_SIGNAL,
308	KEY_CONT_SIGNAL,
309	+ KEY_BIDIRECTIONAL,
310	NO_KEY
311	} current_key;
312
313	@@ -51,6 +52,8 @@ static int header_integer(void *ctx, long val) {
314	case KEY_CONT_SIGNAL:
315	child->cont_signal = val;
316	break;
317	+ case KEY_BIDIRECTIONAL:
318	+ child->bidirectional = val;
319	default:
320	break;
321	}
322	@@ -71,6 +74,8 @@ static int header_map_key(void ctx, const unsigned char stringval, unsigned in
323	current_key = KEY_STOP_SIGNAL;
324	} else if (CHECK_KEY("cont_signal")) {
325	current_key = KEY_CONT_SIGNAL;
326	+ } else if (CHECK_KEY("bidirectional")) {
327	+ current_key = KEY_BIDIRECTIONAL;
328	}
329	return 1;
330	}

335	@@ -160,7 +160,7 @@ void refresh_statusline(void) {
336	xcb_poly_fill_rectangle(xcb_connection, statusline_pm, statusline_clear, 1, &rect);
337
338	/* Draw the text of each block. */
339	- uint32_t x = 0;
340	+ uint32_t x = 0;
341	TAILQ_FOREACH(block, &statusline_head, blocks) {
342	if (i3string_get_num_bytes(block->full_text) == 0)
343	continue;
344	@@ -306,12 +306,14 @@ void handle_button(xcb_button_press_event_t *event) {
345	}
346
347	int32_t x = event->event_x >= 0 ? event->event_x : 0;
348	+ int32_t original_x = x;
349
350	DLOG("Got Button %d\n", event->detail);
351
352	switch (event->detail) {
353	case 1:
354	- /* Left Mousbutton. We determine, which button was clicked
355	+ case 3:
356	+ /* Left or right Mousbutton. We determine, which button was clicked
357	* and set cur_ws accordingly */
358	TAILQ_FOREACH(cur_ws, walk->workspaces, tailq) {
359	DLOG("x = %d\n", x);
360	@@ -321,8 +323,43 @@ void handle_button(xcb_button_press_event_t *event) {
361	x -= cur_ws->name_width + 11;
362	}
363	if (cur_ws == NULL) {
364	+ /* No workspace button was pressed.
365	+ * Check if a status block has been clicked.
366	+ * This of course only has an effect,
367	+ * if the child reported bidirectional protocol usage. */
368	+
369	+ /* First calculate width of tray area */
370	+ trayclient *trayclient;
371	+ int tray_width = 0;
372	+ TAILQ_FOREACH_REVERSE(trayclient, walk->trayclients, tc_head, tailq) {
373	+ if (!trayclient->mapped)
374	+ continue;
375	+ tray_width += (font.height + 2);
376	+ }
377	+
378	+ int block_x = 0, last_block_x;
379	+ int offset = (walk->rect.w - (statusline_width + tray_width)) - 10;
380	+
381	+ x = original_x - offset > 0 ? original_x - offset : 0;
382	+
383	+ struct status_block *block;
384	+
385	+ TAILQ_FOREACH(block, &statusline_head, blocks) {
386	+ last_block_x = block_x;
387	+ block_x += block->width + block->x_offset + block->x_append;
388	+
389	+ if(x <= block_x && x >= last_block_x) {
390	+ send_block_clicked(event->detail, block->name, block->instance, event->root_x, event->root_y);
391	+ return;
392	+ }
393	+ }
394	return;
395	}
396	+ if (event->detail == 3)
397	+ /* Don't actually switch the
398	+ * workspace if it was the right mouse button
399	+ */
400	+ return;
401	break;
402	case 4:
403	/* Mouse wheel up. We select the previous ws, if any.