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Refactor parse_command

Patch status: needinfo

Patch by Tony Crisci

Long description:

Change parse_command to make running commands easier and more efficient.

Caller is now responsible for allocating the yajl_gen and can pass NULL
if generating json is not required.

The CommandResult used as a return value has been typedeffed, contains
more information about the result of the command, and no longer contains
parsing state or a yajl gen.

The CommandResult used during command parsing itself has been renamed to
CommandResultIR to show that it is an intermediate representation of the
result used during parsing. The ConfigResult has been renamed similarly
for consistency.

To apply this patch, use:
curl http://cr.i3wm.org/patch/541/raw.patch | git am

b/generate-command-parser.pl

@@ -131,7 +131,7 @@ close($enumfh);
 
 # Third step: Generate the call function.
 open(my $callfh, '>', "GENERATED_${prefix}_call.h");
-my $resultname = uc(substr($prefix, 0, 1)) . substr($prefix, 1) . 'Result';
+my $resultname = uc(substr($prefix, 0, 1)) . substr($prefix, 1) . 'ResultIR';
 say $callfh "static void GENERATED_call(const int call_identifier, struct $resultname *result) {";
 say $callfh '    switch (call_identifier) {';
 my $call_id = 0;

b/include/commands.h

@@ -12,7 +12,7 @@
 #include "commands_parser.h"
 
 /** The beginning of the prototype for every cmd_ function. */
-#define I3_CMD Match *current_match, struct CommandResult *cmd_output
+#define I3_CMD Match *current_match, struct CommandResultIR *cmd_output
 
 /**
  * Initializes the specified 'Match' data structure and the initial state of

b/include/commands_parser.h

@@ -11,16 +11,11 @@
 
 #include <yajl/yajl_gen.h>
 
-/*
- * Holds the result of a call to any command. When calling
- * parse_command("floating enable, border none"), the parser will internally
- * use a struct CommandResult when calling cmd_floating and cmd_border.
- * parse_command will also return another struct CommandResult, whose
- * json_output is set to a map of individual json_outputs and whose
- * needs_tree_trender is true if any individual needs_tree_render was true.
- *
+/**
+ * An intermediate representation of the result of a command used during
+ * command parsing
  */
-struct CommandResult {
+struct CommandResultIR {
     /* The JSON generator to append a reply to. */
     yajl_gen json_gen;
 
@@ -33,4 +28,29 @@ struct CommandResult {
     bool needs_tree_render;
 };
 
-struct CommandResult *parse_command(const char *input);
+typedef struct CommandResult CommandResult;
+
+/**
+ * A struct that contains useful information about the result of a command
+ */
+struct CommandResult {
+    bool parse_error;
+    /* the error_message is currently only set for parse errors */
+    char *error_message;
+    bool needs_tree_render;
+};
+
+/**
+ * Parses and executes the given command. If a yajl_gen is passed, a json reply
+ * will be generated in the format specified by the ipc protocol. Pass NULL if
+ * no json reply is required.
+ *
+ * Returns a CommandResult struct with useful information about the result of
+ * the command. Free with command_result_free()
+ */
+CommandResult *parse_command(const char *input, yajl_gen gen);
+
+/**
+ * Frees a CommandResult
+ */
+void command_result_free(CommandResult *result);

b/include/config_directives.h

@@ -18,7 +18,7 @@
 uint32_t modifiers_from_str(const char *str);
 
 /** The beginning of the prototype for every cfg_ function. */
-#define I3_CFG Match *current_match, struct ConfigResult *result
+#define I3_CFG Match *current_match, struct ConfigResultIR *result
 
 /* Defines a configuration function, that is, anything that can be called by
  * using 'call cfg_foo()' in parser-specs/.*.spec. Useful so that we don’t need

b/include/config_parser.h

@@ -18,7 +18,7 @@ extern pid_t config_error_nagbar_pid;
  * will be useful in the future when we implement a config parsing IPC command.
  *
  */
-struct ConfigResult {
+struct ConfigResultIR {
     /* The JSON generator to append a reply to. */
     yajl_gen json_gen;
 
@@ -28,7 +28,7 @@ struct ConfigResult {
     int next_state;
 };
 
-struct ConfigResult *parse_config(const char *input, struct context *context);
+struct ConfigResultIR *parse_config(const char *input, struct context *context);
 
 /**
  * Parses the given file by first replacing the variables, then calling

b/src/assignments.c

@@ -45,13 +45,13 @@ void run_assignments(i3Window *window) {
             DLOG("execute command %s\n", current->dest.command);
             char *full_command;
             sasprintf(&full_command, "[id=\"%d\"] %s", window->id, current->dest.command);
-            struct CommandResult *command_output = parse_command(full_command);
+            CommandResult *command_output = parse_command(full_command, NULL);
             free(full_command);
 
             if (command_output->needs_tree_render)
                 needs_tree_render = true;
 
-            yajl_gen_free(command_output->json_gen);
+            command_result_free(command_output);
         }
 
         /* Store that we ran this assignment to not execute it again */

b/src/commands.c

@@ -16,22 +16,29 @@
 #include "shmlog.h"
 
 // Macros to make the YAJL API a bit easier to use.
-#define y(x, ...) yajl_gen_ ## x (cmd_output->json_gen, ##__VA_ARGS__)
-#define ystr(str) yajl_gen_string(cmd_output->json_gen, (unsigned char*)str, strlen(str))
-#define ysuccess(success) do { \
-    y(map_open); \
-    ystr("success"); \
-    y(bool, success); \
-    y(map_close); \
-} while (0)
-#define yerror(message) do { \
-    y(map_open); \
-    ystr("success"); \
-    y(bool, false); \
-    ystr("error"); \
-    ystr(message); \
-    y(map_close); \
-} while (0)
+#define y(x, ...) if (cmd_output->json_gen != NULL) yajl_gen_ ## x (cmd_output->json_gen, ##__VA_ARGS__);
+
+#define ystr(str) if (cmd_output->json_gen != NULL) yajl_gen_string(cmd_output->json_gen, (unsigned char*)str, strlen(str));
+
+#define ysuccess(success) if (cmd_output->json_gen != NULL) { \
+    do { \
+        y(map_open); \
+        ystr("success"); \
+        y(bool, success); \
+        y(map_close); \
+    } while (0); \
+}
+
+#define yerror(message) if (cmd_output->json_gen != NULL) { \
+    do { \
+        y(map_open); \
+        ystr("success"); \
+        y(bool, false); \
+        ystr("error"); \
+        ystr(message); \
+        y(map_close); \
+    } while (0); \
+}
 
 /** When the command did not include match criteria (!), we use the currently
  * focused container. Do not confuse this case with a command which included
@@ -95,7 +102,7 @@ static Output *get_output_of_con(Con *con) {
  * and return true, signaling that no further workspace switching should occur in the calling function.
  *
  */
-static bool maybe_back_and_forth(struct CommandResult *cmd_output, char *name) {
+static bool maybe_back_and_forth(struct CommandResultIR *cmd_output, char *name) {
     Con *ws = con_get_workspace(focused);
 
     /* If we switched to a different workspace, do nothing */

b/src/commands_parser.c

@@ -35,8 +35,8 @@
 #include "all.h"
 
 // Macros to make the YAJL API a bit easier to use.
-#define y(x, ...) yajl_gen_ ## x (command_output.json_gen, ##__VA_ARGS__)
-#define ystr(str) yajl_gen_string(command_output.json_gen, (unsigned char*)str, strlen(str))
+#define y(x, ...) if (command_output.json_gen != NULL) yajl_gen_ ## x (command_output.json_gen, ##__VA_ARGS__)
+#define ystr(str) if (command_output.json_gen != NULL) yajl_gen_string(command_output.json_gen, (unsigned char*)str, strlen(str))
 
 /*******************************************************************************
  * The data structures used for parsing. Essentially the current state and a
@@ -179,8 +179,8 @@ static cmdp_state state;
 #ifndef TEST_PARSER
 static Match current_match;
 #endif
-static struct CommandResult subcommand_output;
-static struct CommandResult command_output;
+static struct CommandResultIR subcommand_output;
+static struct CommandResultIR command_output;
 
 #include "GENERATED_command_call.h"
 
@@ -205,14 +205,24 @@ static void next_state(const cmdp_token *token) {
     }
 }
 
-struct CommandResult *parse_command(const char *input) {
+/*
+ * Parses and executes the given command. If a yajl_gen is passed, a json reply
+ * will be generated in the format specified by the ipc protocol. Pass NULL if
+ * no json reply is required.
+ *
+ * Returns a CommandResult struct with useful information about the result of
+ * the command. Free with command_result_free()
+ */
+CommandResult *parse_command(const char *input, yajl_gen gen) {
     DLOG("COMMAND: *%s*\n", input);
     state = INITIAL;
+    CommandResult *result = scalloc(sizeof(CommandResult));
 
     /* A YAJL JSON generator used for formatting replies. */
-    command_output.json_gen = yajl_gen_alloc(NULL);
+    command_output.json_gen = (gen != NULL ? gen : NULL);
 
     y(array_open);
+
     command_output.needs_tree_render = false;
 
     const char *walk = input;
@@ -378,6 +388,9 @@ struct CommandResult *parse_command(const char *input) {
             ELOG("Your command: %s\n", input);
             ELOG("              %s\n", position);
 
+            result->parse_error = true;
+            result->error_message = errormessage;
+
             /* Format this error message as a JSON reply. */
             y(map_open);
             ystr("success");
@@ -396,7 +409,6 @@ struct CommandResult *parse_command(const char *input) {
             y(map_close);
 
             free(position);
-            free(errormessage);
             clear_stack();
             break;
         }
@@ -404,7 +416,19 @@ struct CommandResult *parse_command(const char *input) {
 
     y(array_close);
 
-    return &command_output;
+    result->needs_tree_render = command_output.needs_tree_render;
+    return result;
+}
+
+/*
+ * Frees a CommandResult
+ */
+void command_result_free(CommandResult *result) {
+    if (result == NULL)
+        return;
+
+    FREE(result->error_message);
+    FREE(result);
 }
 
 /*******************************************************************************
@@ -442,6 +466,10 @@ int main(int argc, char *argv[]) {
         fprintf(stderr, "Syntax: %s <command>\n", argv[0]);
         return 1;
     }
-    parse_command(argv[1]);
+    yajl_gen gen = yajl_gen_alloc(NULL);
+
+    parse_command(argv[1], gen);
+
+    yajl_gen_free(gen);
 }
 #endif

b/src/config_parser.c

@@ -232,8 +232,8 @@ static void clear_criteria(void *unused_criteria) {
 
 static cmdp_state state;
 static Match current_match;
-static struct ConfigResult subcommand_output;
-static struct ConfigResult command_output;
+static struct ConfigResultIR subcommand_output;
+static struct ConfigResultIR command_output;
 
 /* A list which contains the states that lead to the current state, e.g.
  * INITIAL, WORKSPACE_LAYOUT.
@@ -304,7 +304,7 @@ static char *single_line(const char *start) {
     return result;
 }
 
-struct ConfigResult *parse_config(const char *input, struct context *context) {
+struct ConfigResultIR *parse_config(const char *input, struct context *context) {
     /* Dump the entire config file into the debug log. We cannot just use
      * DLOG("%s", input); because one log message must not exceed 4 KiB. */
     const char *dumpwalk = input;
@@ -1000,7 +1000,7 @@ void parse_file(const char *f) {
     context = scalloc(sizeof(struct context));
     context->filename = f;
 
-    struct ConfigResult *config_output = parse_config(new, context);
+    struct ConfigResultIR *config_output = parse_config(new, context);
     yajl_gen_free(config_output->json_gen);
 
     check_for_duplicate_bindings(context);

b/src/ipc.c

@@ -117,20 +117,24 @@ IPC_HANDLER(command) {
     char *command = scalloc(message_size + 1);
     strncpy(command, (const char*)message, message_size);
     LOG("IPC: received: *%s*\n", command);
-    struct CommandResult *command_output = parse_command((const char*)command);
+    yajl_gen gen = yajl_gen_alloc(NULL);
+
+    CommandResult *command_output = parse_command((const char*)command, gen);
     free(command);
 
     if (command_output->needs_tree_render)
         tree_render();
 
+    command_result_free(command_output);
+
     const unsigned char *reply;
     ylength length;
-    yajl_gen_get_buf(command_output->json_gen, &reply, &length);
+    yajl_gen_get_buf(gen, &reply, &length);
 
     ipc_send_message(fd, length, I3_IPC_REPLY_TYPE_COMMAND,
                      (const uint8_t*)reply);
 
-    yajl_gen_free(command_output->json_gen);
+    yajl_gen_free(gen);
 }
 
 static void dump_rect(yajl_gen gen, const char *name, Rect r) {

b/src/key_press.c

@@ -72,9 +72,12 @@ void handle_key_press(xcb_key_press_event_t *event) {
     if (bind == NULL)
         return;
 
+    yajl_gen gen = yajl_gen_alloc(NULL);
+
     char *command_copy = sstrdup(bind->command);
-    struct CommandResult *command_output = parse_command(command_copy);
+    CommandResult *command_output = parse_command(command_copy, gen);
     free(command_copy);
+    command_result_free(command_output);
 
     if (command_output->needs_tree_render)
         tree_render();
@@ -84,7 +87,7 @@ void handle_key_press(xcb_key_press_event_t *event) {
     const unsigned char *reply;
     size_t length;
     yajl_handle handle = yajl_alloc(&command_error_callbacks, NULL, NULL);
-    yajl_gen_get_buf(command_output->json_gen, &reply, &length);
+    yajl_gen_get_buf(gen, &reply, &length);
 
     current_nesting_level = 0;
     parse_error_key = false;
@@ -116,5 +119,5 @@ void handle_key_press(xcb_key_press_event_t *event) {
 
     yajl_free(handle);
 
-    yajl_gen_free(command_output->json_gen);
+    yajl_gen_free(gen);
 }

131	@@ -18,7 +18,7 @@ extern pid_t config_error_nagbar_pid;
132	* will be useful in the future when we implement a config parsing IPC command.
133	*
134	*/
135	-struct ConfigResult {
136	+struct ConfigResultIR {
137	/* The JSON generator to append a reply to. */
138	yajl_gen json_gen;
139
140	@@ -28,7 +28,7 @@ struct ConfigResult {
141	int next_state;
142	};
143
144	-struct ConfigResult parse_config(const char input, struct context *context);
145	+struct ConfigResultIR parse_config(const char input, struct context *context);
146
147	/**
148	* Parses the given file by first replacing the variables, then calling

153	@@ -45,13 +45,13 @@ void run_assignments(i3Window *window) {
154	DLOG("execute command %s\n", current->dest.command);
155	char *full_command;
156	sasprintf(&full_command, "[id=\"%d\"] %s", window->id, current->dest.command);
157	- struct CommandResult *command_output = parse_command(full_command);
158	+ CommandResult *command_output = parse_command(full_command, NULL);
159	free(full_command);
160
161	if (command_output->needs_tree_render)
162	needs_tree_render = true;
163
164	- yajl_gen_free(command_output->json_gen);
165	+ command_result_free(command_output);
166	}
167
168	/* Store that we ran this assignment to not execute it again */

173	@@ -16,22 +16,29 @@
174	#include "shmlog.h"
175
176	// Macros to make the YAJL API a bit easier to use.
177	-#define y(x, ...) yajl_gen_ ## x (cmd_output->json_gen, ##__VA_ARGS__)
178	-#define ystr(str) yajl_gen_string(cmd_output->json_gen, (unsigned char*)str, strlen(str))
179	-#define ysuccess(success) do { \
180	- y(map_open); \
181	- ystr("success"); \
182	- y(bool, success); \
183	- y(map_close); \
184	-} while (0)
185	-#define yerror(message) do { \
186	- y(map_open); \
187	- ystr("success"); \
188	- y(bool, false); \
189	- ystr("error"); \
190	- ystr(message); \
191	- y(map_close); \
192	-} while (0)
193	+#define y(x, ...) if (cmd_output->json_gen != NULL) yajl_gen_ ## x (cmd_output->json_gen, ##__VA_ARGS__);
194	+
195	+#define ystr(str) if (cmd_output->json_gen != NULL) yajl_gen_string(cmd_output->json_gen, (unsigned char*)str, strlen(str));
196	+
197	+#define ysuccess(success) if (cmd_output->json_gen != NULL) { \
198	+ do { \
199	+ y(map_open); \
200	+ ystr("success"); \
201	+ y(bool, success); \
202	+ y(map_close); \
203	+ } while (0); \
204	+}
205	+
206	+#define yerror(message) if (cmd_output->json_gen != NULL) { \
207	+ do { \
208	+ y(map_open); \
209	+ ystr("success"); \
210	+ y(bool, false); \
211	+ ystr("error"); \
212	+ ystr(message); \
213	+ y(map_close); \
214	+ } while (0); \
215	+}
216
217	/** When the command did not include match criteria (!), we use the currently
218	* focused container. Do not confuse this case with a command which included
219	@@ -95,7 +102,7 @@ static Output get_output_of_con(Con con) {
220	* and return true, signaling that no further workspace switching should occur in the calling function.
221	*
222	*/
223	-static bool maybe_back_and_forth(struct CommandResult cmd_output, char name) {
224	+static bool maybe_back_and_forth(struct CommandResultIR cmd_output, char name) {
225	Con *ws = con_get_workspace(focused);
226
227	/* If we switched to a different workspace, do nothing */

232	@@ -35,8 +35,8 @@
233	#include "all.h"
234
235	// Macros to make the YAJL API a bit easier to use.
236	-#define y(x, ...) yajl_gen_ ## x (command_output.json_gen, ##__VA_ARGS__)
237	-#define ystr(str) yajl_gen_string(command_output.json_gen, (unsigned char*)str, strlen(str))
238	+#define y(x, ...) if (command_output.json_gen != NULL) yajl_gen_ ## x (command_output.json_gen, ##__VA_ARGS__)
239	+#define ystr(str) if (command_output.json_gen != NULL) yajl_gen_string(command_output.json_gen, (unsigned char*)str, strlen(str))
240
241	/*******************************************************************************
242	* The data structures used for parsing. Essentially the current state and a
243	@@ -179,8 +179,8 @@ static cmdp_state state;
244	#ifndef TEST_PARSER
245	static Match current_match;
246	#endif
247	-static struct CommandResult subcommand_output;
248	-static struct CommandResult command_output;
249	+static struct CommandResultIR subcommand_output;
250	+static struct CommandResultIR command_output;
251
252	#include "GENERATED_command_call.h"
253
254	@@ -205,14 +205,24 @@ static void next_state(const cmdp_token *token) {
255	}
256	}
257
258	-struct CommandResult parse_command(const char input) {
259	+/*
260	+ * Parses and executes the given command. If a yajl_gen is passed, a json reply
261	+ * will be generated in the format specified by the ipc protocol. Pass NULL if
262	+ * no json reply is required.
263	+ *
264	+ * Returns a CommandResult struct with useful information about the result of
265	+ * the command. Free with command_result_free()
266	+ */
267	+CommandResult parse_command(const char input, yajl_gen gen) {
268	DLOG("COMMAND: %s\n", input);
269	state = INITIAL;
270	+ CommandResult *result = scalloc(sizeof(CommandResult));
271
272	/* A YAJL JSON generator used for formatting replies. */
273	- command_output.json_gen = yajl_gen_alloc(NULL);
274	+ command_output.json_gen = (gen != NULL ? gen : NULL);
275
276	y(array_open);
277	+
278	command_output.needs_tree_render = false;
279
280	const char *walk = input;
281	@@ -378,6 +388,9 @@ struct CommandResult parse_command(const char input) {
282	ELOG("Your command: %s\n", input);
283	ELOG(" %s\n", position);
284
285	+ result->parse_error = true;
286	+ result->error_message = errormessage;
287	+
288	/* Format this error message as a JSON reply. */
289	y(map_open);
290	ystr("success");
291	@@ -396,7 +409,6 @@ struct CommandResult parse_command(const char input) {
292	y(map_close);
293
294	free(position);
295	- free(errormessage);
296	clear_stack();
297	break;
298	}
299	@@ -404,7 +416,19 @@ struct CommandResult parse_command(const char input) {
300
301	y(array_close);
302
303	- return &command_output;
304	+ result->needs_tree_render = command_output.needs_tree_render;
305	+ return result;
306	+}
307	+
308	+/*
309	+ * Frees a CommandResult
310	+ */
311	+void command_result_free(CommandResult *result) {
312	+ if (result == NULL)
313	+ return;
314	+
315	+ FREE(result->error_message);
316	+ FREE(result);
317	}
318
319	/*******************************************************************************
320	@@ -442,6 +466,10 @@ int main(int argc, char *argv[]) {
321	fprintf(stderr, "Syntax: %s <command>\n", argv[0]);
322	return 1;
323	}
324	- parse_command(argv[1]);
325	+ yajl_gen gen = yajl_gen_alloc(NULL);
326	+
327	+ parse_command(argv[1], gen);
328	+
329	+ yajl_gen_free(gen);
330	}
331	#endif

336	@@ -232,8 +232,8 @@ static void clear_criteria(void *unused_criteria) {
337
338	static cmdp_state state;
339	static Match current_match;
340	-static struct ConfigResult subcommand_output;
341	-static struct ConfigResult command_output;
342	+static struct ConfigResultIR subcommand_output;
343	+static struct ConfigResultIR command_output;
344
345	/* A list which contains the states that lead to the current state, e.g.
346	* INITIAL, WORKSPACE_LAYOUT.
347	@@ -304,7 +304,7 @@ static char single_line(const char start) {
348	return result;
349	}
350
351	-struct ConfigResult parse_config(const char input, struct context *context) {
352	+struct ConfigResultIR parse_config(const char input, struct context *context) {
353	/* Dump the entire config file into the debug log. We cannot just use
354	* DLOG("%s", input); because one log message must not exceed 4 KiB. */
355	const char *dumpwalk = input;
356	@@ -1000,7 +1000,7 @@ void parse_file(const char *f) {
357	context = scalloc(sizeof(struct context));
358	context->filename = f;
359
360	- struct ConfigResult *config_output = parse_config(new, context);
361	+ struct ConfigResultIR *config_output = parse_config(new, context);
362	yajl_gen_free(config_output->json_gen);
363
364	check_for_duplicate_bindings(context);

36	@@ -131,7 +131,7 @@ close($enumfh);
37
38	# Third step: Generate the call function.
39	open(my $callfh, '>', "GENERATED_${prefix}_call.h");
40	-my $resultname = uc(substr($prefix, 0, 1)) . substr($prefix, 1) . 'Result';
41	+my $resultname = uc(substr($prefix, 0, 1)) . substr($prefix, 1) . 'ResultIR';
42	say $callfh "static void GENERATED_call(const int call_identifier, struct $resultname *result) {";
43	say $callfh ' switch (call_identifier) {';
44	my $call_id = 0;

49	@@ -12,7 +12,7 @@
50	#include "commands_parser.h"
51
52	/** The beginning of the prototype for every cmd_ function. */
53	-#define I3_CMD Match current_match, struct CommandResult cmd_output
54	+#define I3_CMD Match current_match, struct CommandResultIR cmd_output
55
56	/**
57	* Initializes the specified 'Match' data structure and the initial state of

62	@@ -11,16 +11,11 @@
63
64	#include <yajl/yajl_gen.h>
65
66	-/*
67	- * Holds the result of a call to any command. When calling
68	- * parse_command("floating enable, border none"), the parser will internally
69	- * use a struct CommandResult when calling cmd_floating and cmd_border.
70	- * parse_command will also return another struct CommandResult, whose
71	- * json_output is set to a map of individual json_outputs and whose
72	- * needs_tree_trender is true if any individual needs_tree_render was true.
73	- *
74	+/**
75	+ * An intermediate representation of the result of a command used during
76	+ * command parsing
77	*/
78	-struct CommandResult {
79	+struct CommandResultIR {
80	/* The JSON generator to append a reply to. */
81	yajl_gen json_gen;
82
83	@@ -33,4 +28,29 @@ struct CommandResult {
84	bool needs_tree_render;
85	};
86
87	-struct CommandResult parse_command(const char input);
88	+typedef struct CommandResult CommandResult;
89	+
90	+/**
91	+ * A struct that contains useful information about the result of a command
92	+ */
93	+struct CommandResult {
94	+ bool parse_error;
95	+ /* the error_message is currently only set for parse errors */
96	+ char *error_message;
97	+ bool needs_tree_render;
98	+};
99	+
100	+/**
101	+ * Parses and executes the given command. If a yajl_gen is passed, a json reply
102	+ * will be generated in the format specified by the ipc protocol. Pass NULL if
103	+ * no json reply is required.
104	+ *
105	+ * Returns a CommandResult struct with useful information about the result of
106	+ * the command. Free with command_result_free()
107	+ */
108	+CommandResult parse_command(const char input, yajl_gen gen);
109	+
110	+/**
111	+ * Frees a CommandResult
112	+ */
113	+void command_result_free(CommandResult *result);

118	@@ -18,7 +18,7 @@
119	uint32_t modifiers_from_str(const char *str);
120
121	/** The beginning of the prototype for every cfg_ function. */
122	-#define I3_CFG Match current_match, struct ConfigResult result
123	+#define I3_CFG Match current_match, struct ConfigResultIR result
124
125	/* Defines a configuration function, that is, anything that can be called by
126	* using 'call cfg_foo()' in parser-specs/.*.spec. Useful so that we don’t need

369	@@ -117,20 +117,24 @@ IPC_HANDLER(command) {
370	char *command = scalloc(message_size + 1);
371	strncpy(command, (const char*)message, message_size);
372	LOG("IPC: received: %s\n", command);
373	- struct CommandResult command_output = parse_command((const char)command);
374	+ yajl_gen gen = yajl_gen_alloc(NULL);
375	+
376	+ CommandResult command_output = parse_command((const char)command, gen);
377	free(command);
378
379	if (command_output->needs_tree_render)
380	tree_render();
381
382	+ command_result_free(command_output);
383	+
384	const unsigned char *reply;
385	ylength length;
386	- yajl_gen_get_buf(command_output->json_gen, &reply, &length);
387	+ yajl_gen_get_buf(gen, &reply, &length);
388
389	ipc_send_message(fd, length, I3_IPC_REPLY_TYPE_COMMAND,
390	(const uint8_t*)reply);
391
392	- yajl_gen_free(command_output->json_gen);
393	+ yajl_gen_free(gen);
394	}
395
396	static void dump_rect(yajl_gen gen, const char *name, Rect r) {

401	@@ -72,9 +72,12 @@ void handle_key_press(xcb_key_press_event_t *event) {
402	if (bind == NULL)
403	return;
404
405	+ yajl_gen gen = yajl_gen_alloc(NULL);
406	+
407	char *command_copy = sstrdup(bind->command);
408	- struct CommandResult *command_output = parse_command(command_copy);
409	+ CommandResult *command_output = parse_command(command_copy, gen);
410	free(command_copy);
411	+ command_result_free(command_output);
412
413	if (command_output->needs_tree_render)
414	tree_render();
415	@@ -84,7 +87,7 @@ void handle_key_press(xcb_key_press_event_t *event) {
416	const unsigned char *reply;
417	size_t length;
418	yajl_handle handle = yajl_alloc(&command_error_callbacks, NULL, NULL);
419	- yajl_gen_get_buf(command_output->json_gen, &reply, &length);
420	+ yajl_gen_get_buf(gen, &reply, &length);
421
422	current_nesting_level = 0;
423	parse_error_key = false;
424	@@ -116,5 +119,5 @@ void handle_key_press(xcb_key_press_event_t *event) {
425
426	yajl_free(handle);
427
428	- yajl_gen_free(command_output->json_gen);
429	+ yajl_gen_free(gen);
430	}