From 57a742d82714b4a318cd37efee75469f381f6837 Mon Sep 17 00:00:00 2001
From: koekeishiya <aasvi93@hotmail.com>
Date: Sun, 1 Mar 2020 10:56:38 +0100
Subject: [PATCH] #173 support exclusion for command arguments of type REGEX

---
 CHANGELOG.md         |  1 +
 doc/yabai.1          | 36 +++++++++++-----------
 doc/yabai.asciidoc   | 32 ++++++++++----------
 src/event.c          | 15 +++++++---
 src/event.h          |  2 ++
 src/message.c        | 71 +++++++++++++++++++++++++++++++++++++++-----
 src/rule.h           |  2 ++
 src/window_manager.c |  7 +++--
 8 files changed, 118 insertions(+), 48 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8f3d4905..7d747a10 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 ### Changed
 - Properly return focus to the active window on the current space when a window is moved through a rule [#418](https://github.com/koekeishiya/yabai/issues/418)
 - Prevent space operations (create, destroy, focus, swap, move and send to display) from applying while mission-control is active or the display is animating [#417](https://github.com/koekeishiya/yabai/issues/417)
+- Support exclusion for command arguments of type REGEX [#173](https://github.com/koekeishiya/yabai/issues/173)
 
 ## [2.3.0] - 2020-02-14
 ### Added
diff --git a/doc/yabai.1 b/doc/yabai.1
index bbc4c23f..7bb069ad 100644
--- a/doc/yabai.1
+++ b/doc/yabai.1
@@ -2,12 +2,12 @@
 .\"     Title: yabai
 .\"    Author: [see the "AUTHOR(S)" section]
 .\" Generator: Asciidoctor 2.0.10
-.\"      Date: 2020-02-13
+.\"      Date: 2020-03-01
 .\"    Manual: Yabai Manual
 .\"    Source: Yabai
 .\"  Language: English
 .\"
-.TH "YABAI" "1" "2020-02-13" "Yabai" "Yabai Manual"
+.TH "YABAI" "1" "2020-03-01" "Yabai" "Yabai Manual"
 .ie \n(.g .ds Aq \(aq
 .el       .ds Aq '
 .ss \n[.ss] 0
@@ -494,12 +494,12 @@ Remove an existing rule with the given label.
 Label used to identify the rule with a unique name
 .RE
 .sp
-\fBapp=\fI<REGEX>\fP\fP
+\fBapp[!]=\fI<REGEX>\fP\fP
 .RS 4
 Name of application.
 .RE
 .sp
-\fBtitle=\fI<REGEX>\fP\fP
+\fBtitle[!]=\fI<REGEX>\fP\fP
 .RS 4
 Title of window.
 .RE
@@ -556,7 +556,7 @@ A signal is a simple way for the user to react to some event that has been proce
 yabai \-m signal \fI<COMMAND>\fP
 .SS "COMMAND"
 .sp
-\fB\-\-add event=\fI<EVENT>\fP action=\fI<ACTION>\fP [label=\fI<LABEL>\fP] [app=\fI<REGEX>\fP] [title=\fI<REGEX>\fP]\fP
+\fB\-\-add event=\fI<EVENT>\fP action=\fI<ACTION>\fP [label=\fI<LABEL>\fP] [app[!]=\fI<REGEX>\fP] [title[!]=\fI<REGEX>\fP]\fP
 .RS 4
 Add an optionally labelled signal to execute an action after processing an event of the given type. Some signals can be specified to trigger based on the application name and/or window title.
 .RE
@@ -569,12 +569,12 @@ Remove an existing signal with the given label.
 .sp
 \fBapplication_launched\fP
 .RS 4
-Triggered when a new application is launched. Eligible for \fBapp=\fP filter. Passes one argument: $YABAI_PROCESS_ID
+Triggered when a new application is launched. Eligible for \fBapp\fP filter. Passes one argument: $YABAI_PROCESS_ID
 .RE
 .sp
 \fBapplication_terminated\fP
 .RS 4
-Triggered when an application is terminated. Eligible for \fBapp=\fP filter Passes one argument: $YABAI_PROCESS_ID
+Triggered when an application is terminated. Eligible for \fBapp\fP filter Passes one argument: $YABAI_PROCESS_ID
 .RE
 .sp
 \fBapplication_front_switched\fP
@@ -584,27 +584,27 @@ Triggered when the front\-most application changes. Passes two arguments: $YABAI
 .sp
 \fBapplication_activated\fP
 .RS 4
-Triggered when an application is activated. Eligible for \fBapp=\fP filter. Passes one argument: $YABAI_PROCESS_ID
+Triggered when an application is activated. Eligible for \fBapp\fP filter. Passes one argument: $YABAI_PROCESS_ID
 .RE
 .sp
 \fBapplication_deactivated\fP
 .RS 4
-Triggered when an application is deactivated. Eligible for \fBapp=\fP filter. Passes one argument: $YABAI_PROCESS_ID
+Triggered when an application is deactivated. Eligible for \fBapp\fP filter. Passes one argument: $YABAI_PROCESS_ID
 .RE
 .sp
 \fBapplication_visible\fP
 .RS 4
-Triggered when an application is unhidden. Eligible for \fBapp=\fP filter. Passes one argument: $YABAI_PROCESS_ID
+Triggered when an application is unhidden. Eligible for \fBapp\fP filter. Passes one argument: $YABAI_PROCESS_ID
 .RE
 .sp
 \fBapplication_hidden\fP
 .RS 4
-Triggered when an application is hidden. Eligible for \fBapp=\fP filter. Passes one argument: $YABAI_PROCESS_ID
+Triggered when an application is hidden. Eligible for \fBapp\fP filter. Passes one argument: $YABAI_PROCESS_ID
 .RE
 .sp
 \fBwindow_created\fP
 .RS 4
-Triggered when a window is created. Eligible for both \fBapp=\fP and \fBtitle=\fP filter. Passes one argument: $YABAI_WINDOW_ID
+Triggered when a window is created. Eligible for both \fBapp\fP and \fBtitle\fP filter. Passes one argument: $YABAI_WINDOW_ID
 .RE
 .sp
 \fBwindow_destroyed\fP
@@ -614,32 +614,32 @@ Triggered when a window is destroyed. Passes one argument: $YABAI_WINDOW_ID
 .sp
 \fBwindow_focused\fP
 .RS 4
-Triggered when a window becomes the key\-window for its application. Eligible for both \fBapp=\fP and \fBtitle=\fP filter. Passes one argument: $YABAI_WINDOW_ID
+Triggered when a window becomes the key\-window for its application. Eligible for both \fBapp\fP and \fBtitle\fP filter. Passes one argument: $YABAI_WINDOW_ID
 .RE
 .sp
 \fBwindow_moved\fP
 .RS 4
-Triggered when a window changes position. Eligible for both \fBapp=\fP and \fBtitle=\fP filter. Passes one argument: $YABAI_WINDOW_ID
+Triggered when a window changes position. Eligible for both \fBapp\fP and \fBtitle\fP filter. Passes one argument: $YABAI_WINDOW_ID
 .RE
 .sp
 \fBwindow_resized\fP
 .RS 4
-Triggered when a window changes dimensions. Eligible for both \fBapp=\fP and \fBtitle=\fP filter. Passes one argument: $YABAI_WINDOW_ID
+Triggered when a window changes dimensions. Eligible for both \fBapp\fP and \fBtitle\fP filter. Passes one argument: $YABAI_WINDOW_ID
 .RE
 .sp
 \fBwindow_minimized\fP
 .RS 4
-Triggered when a window has been minimized. Eligible for both \fBapp=\fP and \fBtitle=\fP filter. Passes one argument: $YABAI_WINDOW_ID
+Triggered when a window has been minimized. Eligible for both \fBapp\fP and \fBtitle\fP filter. Passes one argument: $YABAI_WINDOW_ID
 .RE
 .sp
 \fBwindow_deminimized\fP
 .RS 4
-Triggered when a window has been deminimized. Eligible for both \fBapp=\fP and \fBtitle=\fP filter. Passes one argument: $YABAI_WINDOW_ID
+Triggered when a window has been deminimized. Eligible for both \fBapp\fP and \fBtitle\fP filter. Passes one argument: $YABAI_WINDOW_ID
 .RE
 .sp
 \fBwindow_title_changed\fP
 .RS 4
-Triggered when a window changes its title. Eligible for both \fBapp=\fP and \fBtitle=\fP filter. Passes one argument: $YABAI_WINDOW_ID
+Triggered when a window changes its title. Eligible for both \fBapp\fP and \fBtitle\fP filter. Passes one argument: $YABAI_WINDOW_ID
 .RE
 .sp
 \fBspace_changed\fP
diff --git a/doc/yabai.asciidoc b/doc/yabai.asciidoc
index 294a7192..ad0e4a32 100644
--- a/doc/yabai.asciidoc
+++ b/doc/yabai.asciidoc
@@ -377,10 +377,10 @@ ARGUMENT
 *label='<LABEL>'*::
     Label used to identify the rule with a unique name
 
-*app='<REGEX>'*::
+*app[!]='<REGEX>'*::
     Name of application.
 
-*title='<REGEX>'*::
+*title[!]='<REGEX>'*::
     Title of window.
 
 *display='[^]<DISPLAY_SEL>'*::
@@ -423,7 +423,7 @@ yabai -m signal '<COMMAND>'
 COMMAND
 ^^^^^^^
 
-*--add event='<EVENT>' action='<ACTION>' [label='<LABEL>'] [app='<REGEX>'] [title='<REGEX>']*::
+*--add event='<EVENT>' action='<ACTION>' [label='<LABEL>'] [app[!]='<REGEX>'] [title[!]='<REGEX>']*::
     Add an optionally labelled signal to execute an action after processing an event of the given type. Some signals can be specified to trigger based on the application name and/or window title.
 
 *--remove '<LABEL>'*::
@@ -433,49 +433,49 @@ EVENT
 ^^^^^
 
 *application_launched*::
-    Triggered when a new application is launched. Eligible for *app=* filter. Passes one argument: $YABAI_PROCESS_ID
+    Triggered when a new application is launched. Eligible for *app* filter. Passes one argument: $YABAI_PROCESS_ID
 
 *application_terminated*::
-    Triggered when an application is terminated. Eligible for *app=* filter Passes one argument: $YABAI_PROCESS_ID
+    Triggered when an application is terminated. Eligible for *app* filter Passes one argument: $YABAI_PROCESS_ID
 
 *application_front_switched*::
     Triggered when the front-most application changes. Passes two arguments: $YABAI_PROCESS_ID, $YABAI_RECENT_PROCESS_ID
 
 *application_activated*::
-    Triggered when an application is activated. Eligible for *app=* filter. Passes one argument: $YABAI_PROCESS_ID
+    Triggered when an application is activated. Eligible for *app* filter. Passes one argument: $YABAI_PROCESS_ID
 
 *application_deactivated*::
-    Triggered when an application is deactivated. Eligible for *app=* filter. Passes one argument: $YABAI_PROCESS_ID
+    Triggered when an application is deactivated. Eligible for *app* filter. Passes one argument: $YABAI_PROCESS_ID
 
 *application_visible*::
-    Triggered when an application is unhidden. Eligible for *app=* filter. Passes one argument: $YABAI_PROCESS_ID
+    Triggered when an application is unhidden. Eligible for *app* filter. Passes one argument: $YABAI_PROCESS_ID
 
 *application_hidden*::
-    Triggered when an application is hidden. Eligible for *app=* filter. Passes one argument: $YABAI_PROCESS_ID
+    Triggered when an application is hidden. Eligible for *app* filter. Passes one argument: $YABAI_PROCESS_ID
 
 *window_created*::
-    Triggered when a window is created. Eligible for both *app=* and *title=* filter. Passes one argument: $YABAI_WINDOW_ID
+    Triggered when a window is created. Eligible for both *app* and *title* filter. Passes one argument: $YABAI_WINDOW_ID
 
 *window_destroyed*::
     Triggered when a window is destroyed. Passes one argument: $YABAI_WINDOW_ID
 
 *window_focused*::
-    Triggered when a window becomes the key-window for its application. Eligible for both *app=* and *title=* filter. Passes one argument: $YABAI_WINDOW_ID
+    Triggered when a window becomes the key-window for its application. Eligible for both *app* and *title* filter. Passes one argument: $YABAI_WINDOW_ID
 
 *window_moved*::
-    Triggered when a window changes position. Eligible for both *app=* and *title=* filter. Passes one argument: $YABAI_WINDOW_ID
+    Triggered when a window changes position. Eligible for both *app* and *title* filter. Passes one argument: $YABAI_WINDOW_ID
 
 *window_resized*::
-    Triggered when a window changes dimensions. Eligible for both *app=* and *title=* filter. Passes one argument: $YABAI_WINDOW_ID
+    Triggered when a window changes dimensions. Eligible for both *app* and *title* filter. Passes one argument: $YABAI_WINDOW_ID
 
 *window_minimized*::
-    Triggered when a window has been minimized. Eligible for both *app=* and *title=* filter. Passes one argument: $YABAI_WINDOW_ID
+    Triggered when a window has been minimized. Eligible for both *app* and *title* filter. Passes one argument: $YABAI_WINDOW_ID
 
 *window_deminimized*::
-    Triggered when a window has been deminimized. Eligible for both *app=* and *title=* filter. Passes one argument: $YABAI_WINDOW_ID
+    Triggered when a window has been deminimized. Eligible for both *app* and *title* filter. Passes one argument: $YABAI_WINDOW_ID
 
 *window_title_changed*::
-    Triggered when a window changes its title. Eligible for both *app=* and *title=* filter. Passes one argument: $YABAI_WINDOW_ID
+    Triggered when a window changes its title. Eligible for both *app* and *title* filter. Passes one argument: $YABAI_WINDOW_ID
 
 *space_changed*::
     Triggered when the active space has changed. Passes two arguments: $YABAI_SPACE_ID, $YABAI_RECENT_SPACE_ID
diff --git a/src/event.c b/src/event.c
index 4ccbca5d..9820a391 100644
--- a/src/event.c
+++ b/src/event.c
@@ -128,7 +128,8 @@ static bool event_signal_filter(struct signal *signal, enum event_type type, str
         struct process *process = args->entity;
         if (!process) return true;
 
-        return regex_match(signal->app_regex_valid, &signal->app_regex, process->name) == REGEX_MATCH_NO;
+        int regex_match_app = signal->app_regex_exclude ? REGEX_MATCH_YES : REGEX_MATCH_NO;
+        return regex_match(signal->app_regex_valid, &signal->app_regex, process->name) == regex_match_app;
     } break;
     case APPLICATION_ACTIVATED:
     case APPLICATION_DEACTIVATED:
@@ -137,7 +138,8 @@ static bool event_signal_filter(struct signal *signal, enum event_type type, str
         struct application *application = args->entity;
         if (!application) return true;
 
-        return regex_match(signal->app_regex_valid, &signal->app_regex, application->name) == REGEX_MATCH_NO;
+        int regex_match_app = signal->app_regex_exclude ? REGEX_MATCH_YES : REGEX_MATCH_NO;
+        return regex_match(signal->app_regex_valid, &signal->app_regex, application->name) == regex_match_app;
     } break;
     case WINDOW_CREATED:
     case WINDOW_FOCUSED:
@@ -149,8 +151,13 @@ static bool event_signal_filter(struct signal *signal, enum event_type type, str
         struct window *window = args->entity;
         if (!window) return true;
 
-        return regex_match(signal->app_regex_valid,   &signal->app_regex,   window->application->name) == REGEX_MATCH_NO ||
-               regex_match(signal->title_regex_valid, &signal->title_regex, args->param1)              == REGEX_MATCH_NO;
+        int regex_match_app = signal->app_regex_exclude ? REGEX_MATCH_YES : REGEX_MATCH_NO;
+        bool app_no_match = regex_match(signal->app_regex_valid,   &signal->app_regex,   window->application->name) == regex_match_app;
+
+        int regex_match_title = signal->title_regex_exclude ? REGEX_MATCH_YES : REGEX_MATCH_NO;
+        bool title_no_match = regex_match(signal->title_regex_valid, &signal->title_regex, args->param1)            == regex_match_title;
+
+        return app_no_match || title_no_match;
     } break;
     }
 }
diff --git a/src/event.h b/src/event.h
index c0a00e3b..00a11d5f 100644
--- a/src/event.h
+++ b/src/event.h
@@ -185,6 +185,8 @@ struct signal
 {
     bool app_regex_valid;
     bool title_regex_valid;
+    bool app_regex_exclude;
+    bool title_regex_exclude;
     regex_t app_regex;
     regex_t title_regex;
     char *command;
diff --git a/src/message.c b/src/message.c
index b3355000..ffa72f58 100644
--- a/src/message.c
+++ b/src/message.c
@@ -279,20 +279,33 @@ static struct token get_token(char **message)
     return token;
 }
 
-static void get_key_value_pair(char *token, char **key, char **value)
+static void get_key_value_pair(char *token, char **key, char **value, bool *exclusion)
 {
     *key = token;
 
-    while (*token && *token != '=') {
+    while (*token) {
+        char fst = token[0];
+        char snd = token[1];
+
+        if (fst == '!' && snd == '=') {
+            break;
+        } else if (fst == '=') {
+            break;
+        }
+
         ++token;
     }
 
-    if (*token != '=') {
+    int index = (token[0] == '!' && token[1] == '=') ? 2 : 1;
+    char check = (index == 2) ? '!' : '=';
+
+    if (*token != check) {
         *key = NULL;
         *value = NULL;
-    } else if (token[1]) {
+    } else if (token[index]) {
         *token = '\0';
-        *value = token+1;
+        *value = token+index;
+        *exclusion = index == 2;
     } else {
         *value = NULL;
     }
@@ -1756,6 +1769,7 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
 {
     struct token command = get_token(&message);
     if (token_equals(command, COMMAND_RULE_ADD)) {
+        char *unsupported_exclusion = NULL;
         bool did_parse = true;
         bool has_filter = false;
         struct rule rule = {};
@@ -1764,7 +1778,8 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
         while (token.text && token.length > 0) {
             char *key = NULL;
             char *value = NULL;
-            get_key_value_pair(token.text, &key, &value);
+            bool exclusion = false;
+            get_key_value_pair(token.text, &key, &value, &exclusion);
 
             if (!key || !value) {
                 daemon_fail(rsp, "invalid key-value pair '%s'\n", token.text);
@@ -1773,9 +1788,11 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
             }
 
             if (string_equals(key, ARGUMENT_RULE_KEY_LABEL)) {
+                if (exclusion) unsupported_exclusion = key;
                 rule.label = string_copy(value);
             } else if (string_equals(key, ARGUMENT_RULE_KEY_APP)) {
                 has_filter = true;
+                rule.app_regex_exclude = exclusion;
                 rule.app_regex_valid = regcomp(&rule.app_regex, value, REG_EXTENDED) == 0;
                 if (!rule.app_regex_valid) {
                     daemon_fail(rsp, "invalid regex pattern '%s' for key '%s'\n", value, key);
@@ -1783,12 +1800,15 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_TITLE)) {
                 has_filter = true;
+                rule.title_regex_exclude = exclusion;
                 rule.title_regex_valid = regcomp(&rule.title_regex, value, REG_EXTENDED) == 0;
                 if (!rule.title_regex_valid) {
                     daemon_fail(rsp, "invalid regex pattern '%s' for key '%s'\n", value, key);
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_DISPLAY)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 if (value[0] == ARGUMENT_RULE_VALUE_SPACE) {
                     ++value;
                     rule.follow_space = true;
@@ -1801,6 +1821,8 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_SPACE)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 if (value[0] == ARGUMENT_RULE_VALUE_SPACE) {
                     ++value;
                     rule.follow_space = true;
@@ -1813,6 +1835,8 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_GRID)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 if ((sscanf(value, ARGUMENT_RULE_VALUE_GRID,
                             &rule.grid[0], &rule.grid[1],
                             &rule.grid[2], &rule.grid[3],
@@ -1821,11 +1845,15 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_ALPHA)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 if (sscanf(value, "%f", &rule.alpha) != 1) {
                     daemon_fail(rsp, "invalid value '%s' for key '%s'\n", value, key);
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_MANAGE)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 if (string_equals(value, ARGUMENT_COMMON_VAL_ON)) {
                     rule.manage = RULE_PROP_ON;
                 } else if (string_equals(value, ARGUMENT_COMMON_VAL_OFF)) {
@@ -1835,6 +1863,8 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_STICKY)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 if (string_equals(value, ARGUMENT_COMMON_VAL_ON)) {
                     rule.sticky = RULE_PROP_ON;
                 } else if (string_equals(value, ARGUMENT_COMMON_VAL_OFF)) {
@@ -1844,6 +1874,8 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_ON_TOP)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 if (string_equals(value, ARGUMENT_COMMON_VAL_ON)) {
                     rule.topmost = RULE_PROP_ON;
                 } else if (string_equals(value, ARGUMENT_COMMON_VAL_OFF)) {
@@ -1853,6 +1885,8 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_BORDER)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 if (string_equals(value, ARGUMENT_COMMON_VAL_ON)) {
                     rule.border = RULE_PROP_ON;
                 } else if (string_equals(value, ARGUMENT_COMMON_VAL_OFF)) {
@@ -1862,6 +1896,8 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_RULE_KEY_FULLSCR)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 if (string_equals(value, ARGUMENT_COMMON_VAL_ON)) {
                     rule.fullscreen = RULE_PROP_ON;
                 } else if (string_equals(value, ARGUMENT_COMMON_VAL_OFF)) {
@@ -1880,7 +1916,12 @@ static void handle_domain_rule(FILE *rsp, struct token domain, char *message)
         }
 
         if (!has_filter) {
-            daemon_fail(rsp, "missing required key-value pair 'app=..' or 'title=..'\n");
+            daemon_fail(rsp, "missing required key-value pair 'app[!]=..' or 'title[!]=..'\n");
+            did_parse = false;
+        }
+
+        if (unsupported_exclusion) {
+            daemon_fail(rsp, "unsupported token '!' (exclusion) given for key '%s'\n", unsupported_exclusion);
             did_parse = false;
         }
 
@@ -1908,6 +1949,7 @@ static void handle_domain_signal(FILE *rsp, struct token domain, char *message)
 {
     struct token command = get_token(&message);
     if (token_equals(command, COMMAND_SIGNAL_ADD)) {
+        char *unsupported_exclusion = NULL;
         bool did_parse = true;
         bool has_command = false;
         bool has_signal_type = false;
@@ -1918,7 +1960,8 @@ static void handle_domain_signal(FILE *rsp, struct token domain, char *message)
         while (token.text && token.length > 0) {
             char *key = NULL;
             char *value = NULL;
-            get_key_value_pair(token.text, &key, &value);
+            bool exclusion = false;
+            get_key_value_pair(token.text, &key, &value, &exclusion);
 
             if (!key || !value) {
                 daemon_fail(rsp, "invalid key-value pair '%s'\n", token.text);
@@ -1927,23 +1970,30 @@ static void handle_domain_signal(FILE *rsp, struct token domain, char *message)
             }
 
             if (string_equals(key, ARGUMENT_SIGNAL_KEY_LABEL)) {
+                if (exclusion) unsupported_exclusion = key;
                 signal.label = string_copy(value);
             } else if (string_equals(key, ARGUMENT_SIGNAL_KEY_APP)) {
+                signal.app_regex_exclude = exclusion;
                 signal.app_regex_valid = regcomp(&signal.app_regex, value, REG_EXTENDED) == 0;
                 if (!signal.app_regex_valid) {
                     daemon_fail(rsp, "invalid regex pattern '%s' for key '%s'\n", value, key);
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_SIGNAL_KEY_TITLE)) {
+                signal.title_regex_exclude = exclusion;
                 signal.title_regex_valid = regcomp(&signal.title_regex, value, REG_EXTENDED) == 0;
                 if (!signal.title_regex_valid) {
                     daemon_fail(rsp, "invalid regex pattern '%s' for key '%s'\n", value, key);
                     did_parse = false;
                 }
             } else if (string_equals(key, ARGUMENT_SIGNAL_KEY_ACTION)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 has_command = true;
                 signal.command = string_copy(value);
             } else if (string_equals(key, ARGUMENT_SIGNAL_KEY_EVENT)) {
+                if (exclusion) unsupported_exclusion = key;
+
                 has_signal_type = true;
                 signal_type = event_type_from_string(value);
                 if (signal_type == EVENT_TYPE_UNKNOWN) {
@@ -1969,6 +2019,11 @@ static void handle_domain_signal(FILE *rsp, struct token domain, char *message)
             did_parse = false;
         }
 
+        if (unsupported_exclusion) {
+            daemon_fail(rsp, "unsupported token '!' (exclusion) given for key '%s'\n", unsupported_exclusion);
+            did_parse = false;
+        }
+
         if (did_parse) {
             event_signal_add(signal_type, &signal);
         } else {
diff --git a/src/rule.h b/src/rule.h
index b1fc5dcb..a0635868 100644
--- a/src/rule.h
+++ b/src/rule.h
@@ -12,6 +12,8 @@ struct rule
     regex_t title_regex;
     bool app_regex_valid;
     bool title_regex_valid;
+    bool app_regex_exclude;
+    bool title_regex_exclude;
     bool follow_space;
     uint32_t did;
     uint64_t sid;
diff --git a/src/window_manager.c b/src/window_manager.c
index 4e0a7a2d..2f43a84f 100644
--- a/src/window_manager.c
+++ b/src/window_manager.c
@@ -119,8 +119,11 @@ void window_manager_query_windows_for_displays(FILE *rsp)
 
 void window_manager_apply_rule_to_window(struct space_manager *sm, struct window_manager *wm, struct window *window, struct rule *rule)
 {
-    if (regex_match(rule->app_regex_valid,   &rule->app_regex,   window->application->name) == REGEX_MATCH_NO) return;
-    if (regex_match(rule->title_regex_valid, &rule->title_regex, window_title(window))      == REGEX_MATCH_NO) return;
+    int regex_match_app = rule->app_regex_exclude ? REGEX_MATCH_YES : REGEX_MATCH_NO;
+    if (regex_match(rule->app_regex_valid,   &rule->app_regex,   window->application->name) == regex_match_app)   return;
+
+    int regex_match_title = rule->title_regex_exclude ? REGEX_MATCH_YES : REGEX_MATCH_NO;
+    if (regex_match(rule->title_regex_valid, &rule->title_regex, window_title(window))      == regex_match_title) return;
 
     if (rule->sid || rule->did) {
         if (!window_is_fullscreen(window) && !space_is_fullscreen(window_space(window))) {