Fix segfault for bspc subscribe -f report

`sb->stream` is `NULL` in `add_subscriber` when called with `--fifo` option.
Also make first report message be taken into account for `--count` option.

src/messages.c

@@ -84,8 +84,6 @@ void handle_message(char *msg, int msg_len, FILE *rsp)
 
 void process_message(char **args, int num, FILE *rsp)
 {
-	int ret = SUBSCRIBE_FAILURE;
-
 	if (streq("node", *args)) {
 		cmd_node(++args, --num, rsp);
 	} else if (streq("desktop", *args)) {
@@ -95,7 +93,8 @@ void process_message(char **args, int num, FILE *rsp)
 	} else if (streq("query", *args)) {
 		cmd_query(++args, --num, rsp);
 	} else if (streq("subscribe", *args)) {
-		ret = cmd_subscribe(++args, --num, rsp);
+		cmd_subscribe(++args, --num, rsp);
+		return;
 	} else if (streq("wm", *args)) {
 		cmd_wm(++args, --num, rsp);
 	} else if (streq("rule", *args)) {
@@ -109,10 +108,7 @@ void process_message(char **args, int num, FILE *rsp)
 	}
 
 	fflush(rsp);
-
+	fclose(rsp);
-	if (ret != SUBSCRIBE_SOCKET) {
-		fclose(rsp);
-	}
 }
 
 void cmd_node(char **args, int num, FILE *rsp)
@@ -1237,52 +1233,68 @@ void cmd_wm(char **args, int num, FILE *rsp)
 	}
 }
 
-int cmd_subscribe(char **args, int num, FILE *rsp)
+void cmd_subscribe(char **args, int num, FILE *rsp)
 {
 	int field = 0;
 	int count = -1;
 	FILE *stream = rsp;
 	char *fifo_path = NULL;
+	subscriber_mask_t mask;
 
-	if (num < 1) {
+	while (num > 0) {
-		field = SBSC_MASK_REPORT;
+		if (streq("-c", *args) || streq("--count", *args)) {
-	} else {
-		subscriber_mask_t mask;
-		while (num > 0) {
-			if (streq("-c", *args) || streq("--count", *args)) {
-				num--, args++;
-				if (num < 1) {
-					fail(rsp, "subscribe %s: Not enough arguments.\n", *(args - 1));
-					return SUBSCRIBE_FAILURE;
-				}
-				if (sscanf(*args, "%i", &count) != 1 || count < 1) {
-					fail(rsp, "subscribe %s: Invalid argument: '%s'.\n", *(args - 1), *args);
-					return SUBSCRIBE_FAILURE;
-				}
-			} else if (streq("-f", *args) || streq("--fifo", *args)) {
-				fifo_path = mktempfifo(FIFO_TEMPLATE);
-				if (fifo_path == NULL) {
-					fail(rsp, "subscribe %s: Can't create FIFO.\n", *(args - 1));
-					return SUBSCRIBE_FAILURE;
-				}
-				stream = NULL;
-				fprintf(rsp, "%s\n", fifo_path);
-			} else if (parse_subscriber_mask(*args, &mask)) {
-				field |= mask;
-			} else {
-				fail(rsp, "subscribe: Invalid argument: '%s'.\n", *args);
-				return SUBSCRIBE_FAILURE;
-			}
 			num--, args++;
+			if (num < 1) {
+				fail(rsp, "subscribe %s: Not enough arguments.\n", *(args - 1));
+				goto failed;
+			}
+			if (sscanf(*args, "%i", &count) != 1 || count < 1) {
+				fail(rsp, "subscribe %s: Invalid argument: '%s'.\n", *(args - 1), *args);
+				goto failed;
+			}
+		} else if (streq("-f", *args) || streq("--fifo", *args)) {
+			fifo_path = mktempfifo(FIFO_TEMPLATE);
+			if (fifo_path == NULL) {
+				fail(rsp, "subscribe %s: Can't create FIFO.\n", *(args - 1));
+				goto failed;
+			}
+		} else if (parse_subscriber_mask(*args, &mask)) {
+			field |= mask;
+		} else {
+			fail(rsp, "subscribe: Invalid argument: '%s'.\n", *args);
+			goto failed;
+		}
+		num--, args++;
+	}
+
+	if (field == 0) {
+		field = SBSC_MASK_REPORT;
+	}
+
+	if (fifo_path) {
+		fprintf(rsp, "%s\n", fifo_path);
+		fflush(rsp);
+		fclose(rsp);
+
+		stream = fopen(fifo_path, "w");
+
+		if (stream == NULL) {
+			perror("subscribe: fopen");
+			goto free_fifo_path;
 		}
 	}
 
 	add_subscriber(stream, fifo_path, field, count);
+	return;
 
-	if (stream != NULL) {
+failed:
-		return SUBSCRIBE_SOCKET;
+	fflush(rsp);
-	} else {
+	fclose(rsp);
-		return SUBSCRIBE_FIFO;
+
+free_fifo_path:
+	if (fifo_path) {
+		unlink(fifo_path);
+		free(fifo_path);
 	}
 }
 

src/messages.h

@@ -28,12 +28,6 @@
 #include "types.h"
 #include "subscribe.h"
 
-enum {
-	SUBSCRIBE_SOCKET,
-	SUBSCRIBE_FIFO,
-	SUBSCRIBE_FAILURE
-};
-
 void handle_message(char *msg, int msg_len, FILE *rsp);
 void process_message(char **args, int num, FILE *rsp);
 void cmd_node(char **args, int num, FILE *rsp);
@@ -42,7 +36,7 @@ void cmd_monitor(char **args, int num, FILE *rsp);
 void cmd_query(char **args, int num, FILE *rsp);
 void cmd_rule(char **args, int num, FILE *rsp);
 void cmd_wm(char **args, int num, FILE *rsp);
-int cmd_subscribe(char **args, int num, FILE *rsp);
+void cmd_subscribe(char **args, int num, FILE *rsp);
 void cmd_quit(char **args, int num, FILE *rsp);
 void cmd_config(char **args, int num, FILE *rsp);
 void set_setting(coordinates_t loc, char *name, char *value, FILE *rsp);

src/subscribe.c

@@ -80,6 +80,9 @@ void add_subscriber(FILE *stream, char* fifo_path, int field, int count)
 	}
 	if (sb->field & SBSC_MASK_REPORT) {
 		print_report(sb->stream);
+		if (sb->count-- == 1) {
+			remove_subscriber(sb);
+		}
 	}
 }
 
@@ -137,9 +140,6 @@ void put_status(subscriber_mask_t mask, ...)
 			if (sb->count > 0) {
 				sb->count--;
 			}
-			if (sb->stream == NULL) {
-				sb->stream = fopen(sb->fifo_path, "w");
-			}
 			if (mask == SBSC_MASK_REPORT) {
 				ret = print_report(sb->stream);
 			} else {