add hotload functionality

The hotload feature is disabled by default and can be controlled via --hotload <boolean>.
When enabled, a change to any file in the CONFIG_DIR will lead to an automatic reload of the config.
When a hotload event occurs, all items are removed and all settings/defaults are reset.
Then the sketchybarrc is executed again, which gives the same effect as restarting the program manually.

makefile

@@ -14,7 +14,9 @@ SRC      = src
 _OBJ = alias.o background.o bar_item.o custom_events.o event.o graph.o \
        image.o mouse.o shadow.o font.o text.o message.o mouse.o bar.o color.o \
        window.o bar_manager.o display.o event_loop.o group.o mach.o popup.o \
-       animation.o workspace.om volume.o slider.o power.o wifi.om media.om
+       animation.o workspace.om volume.o slider.o power.o wifi.om media.om \
+			 hotload.o
+
 OBJ  = $(patsubst %, $(ODIR)/%, $(_OBJ))
 
 .PHONY: all clean arm x86 profile leak universal

src/animation.c

@@ -245,3 +245,18 @@ bool animator_update(struct animator* animator) {
 
   return needs_refresh;
 }
+
+void animator_destroy(struct animator* animator) {
+  if (animator->animation_count > 0) {
+    CFRunLoopRemoveTimer(CFRunLoopGetMain(),
+                         animator->clock,
+                         kCFRunLoopCommonModes);
+    CFRelease(animator->clock);
+
+    for (int i = 0; i < animator->animation_count; i++) {
+      animation_destroy(animator->animations[i]);
+    }
+  }
+
+  if (animator->animations) free(animator->animations);
+}

src/animation.h

@@ -120,3 +120,4 @@ bool animator_cancel(struct animator* animator, void* target, animator_function*
 void animator_cancel_locked(struct animator* animator, void* target, animator_function* function);
 bool animator_update(struct animator* animator);
 void animator_lock(struct animator* animator);
+void animator_destroy(struct animator* animator);

src/bar_item.c

@@ -760,7 +760,7 @@ void bar_item_inherit_from_item(struct bar_item* bar_item, struct bar_item* ance
   }
 }
 
-void bar_item_destroy(struct bar_item* bar_item) {
+void bar_item_destroy(struct bar_item* bar_item, bool free_memory) {
   if (bar_item->name) free(bar_item->name);
   if (bar_item->script) free(bar_item->script);
   if (bar_item->click_script) free(bar_item->click_script);
@@ -786,7 +786,7 @@ void bar_item_destroy(struct bar_item* bar_item) {
   }
   if (bar_item->windows) free(bar_item->windows);
 
-  free(bar_item);
+  if (free_memory) free(bar_item);
 }
 
 void bar_item_serialize(struct bar_item* bar_item, FILE* rsp) {

src/bar_item.h

@@ -99,7 +99,7 @@ struct bar_item* bar_item_create();
 void bar_item_inherit_from_item(struct bar_item* bar_item, struct bar_item* ancestor);
 void bar_item_init(struct bar_item* bar_item, struct bar_item* default_item);
 void bar_item_serialize(struct bar_item* bar_item, FILE* rsp);
-void bar_item_destroy(struct bar_item* bar_item);
+void bar_item_destroy(struct bar_item* bar_item, bool free_memory);
 
 bool bar_item_is_shown(struct bar_item* bar_item);
 void bar_item_needs_update(struct bar_item* bar_item);

src/bar_manager.c

@@ -23,6 +23,7 @@ void bar_manager_init(struct bar_manager* bar_manager) {
   bar_manager->bar_needs_update = false;
   bar_manager->bars = NULL;
   bar_manager->bar_count = 0;
+  bar_manager->bar_items = NULL;
   bar_manager->bar_item_count = 0;
   bar_manager->displays = DISPLAY_ALL_PATTERN;
   bar_manager->position = POSITION_TOP;
@@ -169,7 +170,7 @@ void bar_manager_remove_item(struct bar_manager* bar_manager, struct bar_item* b
            sizeof(struct bar_item*)*bar_manager->bar_item_count);
   }
 
-  bar_item_destroy(bar_item);
+  bar_item_destroy(bar_item, true);
 }
 
 bool bar_manager_set_margin(struct bar_manager* bar_manager, int margin) {
@@ -991,17 +992,27 @@ void bar_manager_handle_notification(struct bar_manager* bar_manager, struct not
 }
 
 void bar_manager_destroy(struct bar_manager* bar_manager) {
+  animator_destroy(&bar_manager->animator);
+
   for (int i = 0; i < bar_manager->bar_item_count; i++) {
-    bar_item_destroy(bar_manager->bar_items[i]);
+    bar_item_destroy(bar_manager->bar_items[i], true);
   }
   if (bar_manager->bar_items) free(bar_manager->bar_items);
   for (int i = 0; i < bar_manager->bar_count; i++) {
     bar_destroy(bar_manager->bars[i]);
   }
+
+  bar_item_destroy(&bar_manager->default_item, false);
   custom_events_destroy(&bar_manager->custom_events);
   background_destroy(&bar_manager->background);
 
   if (bar_manager->bars) free(bar_manager->bars);
+  CFRunLoopRemoveTimer(CFRunLoopGetMain(),
+                       bar_manager->clock,
+                       kCFRunLoopCommonModes);
+
+  CFRunLoopTimerInvalidate(bar_manager->clock);
+  CFRelease(bar_manager->clock);
 }
 
 void bar_manager_serialize(struct bar_manager* bar_manager, FILE* rsp) {

src/custom_events.c

@@ -17,6 +17,7 @@ void custom_event_destroy(struct custom_event* custom_event) {
 
 void custom_events_init(struct custom_events* custom_events) {
   custom_events->count = 0;
+  custom_events->events = NULL;
 
   // System Events
   custom_events_append(custom_events, string_copy(COMMAND_SUBSCRIBE_FRONT_APP_SWITCHED), NULL);

src/event.c

@@ -1,5 +1,6 @@
 #include "event.h"
 #include "event_loop.h"
+#include "hotload.h"
 
 extern struct event_loop g_event_loop;
 extern struct bar_manager g_bar_manager;
@@ -388,3 +389,11 @@ EVENT_CALLBACK(EVENT_HANDLER_MEDIA_CHANGED) {
   free(context);
   return EVENT_SUCCESS;
 }
+
+EVENT_CALLBACK(EVENT_HANDLER_HOTLOAD) {
+  bar_manager_destroy(&g_bar_manager);
+  bar_manager_init(&g_bar_manager);
+  bar_manager_begin(&g_bar_manager);
+  exec_config_file();
+  return EVENT_SUCCESS;
+}

src/event.h

@@ -33,6 +33,7 @@ EVENT_CALLBACK(EVENT_HANDLER_BRIGHTNESS_CHANGED);
 EVENT_CALLBACK(EVENT_HANDLER_POWER_SOURCE_CHANGED);
 EVENT_CALLBACK(EVENT_HANDLER_MEDIA_CHANGED);
 EVENT_CALLBACK(EVENT_HANDLER_DISTRIBUTED_NOTIFICATION);
+EVENT_CALLBACK(EVENT_HANDLER_HOTLOAD);
 
 #define EVENT_QUEUED     0x0
 #define EVENT_PROCESSED  0x1
@@ -70,6 +71,7 @@ enum event_type {
     POWER_SOURCE_CHANGED,
     MEDIA_CHANGED,
     DISTRIBUTED_NOTIFICATION,
+    HOTLOAD,
 
     EVENT_TYPE_COUNT
 };
@@ -101,6 +103,7 @@ static const char *event_type_str[] = {
     [POWER_SOURCE_CHANGED]           = "power_source_changed",
     [MEDIA_CHANGED]                  = "media_changed",
     [DISTRIBUTED_NOTIFICATION]       = "distributed_notification",
+    [HOTLOAD]                        = "hotload",
 
     [EVENT_TYPE_COUNT]               = "event_type_count"
 };
@@ -131,6 +134,7 @@ static event_callback *event_handler[] = {
     [SHELL_REFRESH]                  = EVENT_HANDLER_SHELL_REFRESH,
     [ANIMATOR_REFRESH]               = EVENT_HANDLER_ANIMATOR_REFRESH,
     [MACH_MESSAGE]                   = EVENT_HANDLER_MACH_MESSAGE,
+    [HOTLOAD]                        = EVENT_HANDLER_HOTLOAD,
 };
 
 struct event {

src/hotload.c

@@ -0,0 +1,101 @@
+#include "bar_manager.h"
+#include "event.h"
+#include <ApplicationServices/ApplicationServices.h>
+#include <libgen.h>
+
+extern char g_config_file[4096];
+extern char g_name[256];
+pthread_mutex_t hotload_lock;
+bool g_hotload = false;
+
+void hotload_set_state(int state) {
+  g_hotload = state;
+}
+
+int hotload_get_state() {
+  return g_hotload;
+}
+
+static bool get_config_file(char *restrict filename, char *restrict buffer, int buffer_size) {
+  char *xdg_home = getenv("XDG_CONFIG_HOME");
+  if (xdg_home && *xdg_home) {
+    snprintf(buffer, buffer_size, "%s/%s/%s", xdg_home, g_name, filename);
+    if (file_exists(buffer)) return true;
+  }
+
+  char *home = getenv("HOME");
+  if (!home) return false;
+
+  snprintf(buffer, buffer_size, "%s/.config/%s/%s", home, g_name, filename);
+  if (file_exists(buffer)) return true;
+
+  snprintf(buffer, buffer_size, "%s/.%s", home, filename);
+  return file_exists(buffer);
+}
+
+void exec_config_file() {
+  if (!*g_config_file
+    && !get_config_file("sketchybarrc", g_config_file, sizeof(g_config_file))) {
+    printf("could not locate config file..\n");
+    return;
+  }
+
+  if (!file_exists(g_config_file)) {
+    printf("file '%s' does not exist..\n", g_config_file);
+    return;
+  }
+
+  setenv("CONFIG_DIR", dirname(g_config_file), 1);
+
+  if (!ensure_executable_permission(g_config_file)) {
+    printf("could not set the executable permission bit for '%s'\n", g_config_file);
+    return;
+  }
+
+  if (!fork_exec(g_config_file, NULL)) {
+    printf("failed to execute file '%s'\n", g_config_file);
+    return;
+  }
+}
+
+static void handler(ConstFSEventStreamRef stream,
+             void* context,
+             size_t count,
+             void* paths,
+             const FSEventStreamEventFlags* flags,
+             const FSEventStreamEventId* ids) {
+  if (g_hotload && count > 0) {
+    struct event *event = event_create(&g_event_loop, HOTLOAD, NULL);
+    event_loop_post(&g_event_loop, event); 
+  }
+}
+
+int begin_receiving_config_change_events() {
+  char* file = dirname(g_config_file);
+  CFStringRef file_ref = CFStringCreateWithCString(
+                             kCFAllocatorDefault, file, kCFStringEncodingUTF8);
+
+  CFArrayRef paths = CFArrayCreate(NULL,
+                                   (const void**)&file_ref,
+                                   1,
+                                   &kCFTypeArrayCallBacks);
+
+  FSEventStreamRef stream = FSEventStreamCreate(
+                                         kCFAllocatorDefault,
+                                         handler,
+                                         NULL,
+                                         paths,
+                                         kFSEventStreamEventIdSinceNow,
+                                         0.5,
+                                         kFSEventStreamCreateFlagNoDefer
+                                         | kFSEventStreamCreateFlagFileEvents);
+
+  CFRelease(file_ref);
+  CFRelease(paths);
+
+  FSEventStreamScheduleWithRunLoop(stream, CFRunLoopGetCurrent(),
+                                           kCFRunLoopDefaultMode);
+
+  FSEventStreamStart(stream);
+  return 0;
+}

src/hotload.h

@@ -0,0 +1,9 @@
+#include <stdbool.h>
+
+#define HOTLOAD_STATE_ENABLED true
+#define HOTLOAD_STATE_DISABLED false
+
+void exec_config_file();
+void begin_receiving_config_change_events();
+void hotload_set_state(int state);
+int hotload_get_state();

src/message.c

@@ -1,5 +1,6 @@
 #include "message.h"
 #include "misc/defines.h"
+#include "hotload.h"
 
 extern struct event_loop g_event_loop;
 extern struct bar_manager g_bar_manager;
@@ -696,6 +697,9 @@ void handle_message_mach(struct mach_buffer* buffer) {
     } else if (token_equals(command, DOMAIN_EXIT)) {
       bar_manager_destroy(&g_bar_manager);
       exit(0);
+    } else if (token_equals(command, DOMAIN_HOTLOAD)) {
+      struct token token = get_token(&message);
+      hotload_set_state(evaluate_boolean_state(token, hotload_get_state()));
     } else {
       char* rbr_msg = get_batch_line(&message);
       respond(rsp, "[!] Unknown domain '%s'\n", command.text);

src/misc/defines.h

@@ -30,6 +30,8 @@
 
 #define DOMAIN_EXIT                            "--exit"
 
+#define DOMAIN_HOTLOAD                         "--hotload"
+
 #define SUB_DOMAIN_ICON                        "icon"
 #define SUB_DOMAIN_LABEL                       "label"
 #define SUB_DOMAIN_BACKGROUND                  "background"

src/sketchybar.c

@@ -7,22 +7,23 @@
 #include "power.h"
 #include "wifi.h"
 #include "misc/help.h"
-#include <libgen.h>
 #include "media.h"
+#include "hotload.h"
+#include <libgen.h>
 
-#define LCFILE_PATH_FMT         "/tmp/%s_%s.lock"
+#define LCFILE_PATH_FMT  "/tmp/%s_%s.lock"
 
-#define CLIENT_OPT_LONG         "--message"
-#define CLIENT_OPT_SHRT         "-m"
+#define CLIENT_OPT_LONG  "--message"
+#define CLIENT_OPT_SHRT  "-m"
 
-#define VERSION_OPT_LONG        "--version"
-#define VERSION_OPT_SHRT        "-v"
+#define VERSION_OPT_LONG "--version"
+#define VERSION_OPT_SHRT "-v"
 
-#define CONFIG_OPT_LONG         "--config"
-#define CONFIG_OPT_SHRT         "-c"
+#define CONFIG_OPT_LONG  "--config"
+#define CONFIG_OPT_SHRT  "-c"
 
-#define HELP_OPT_LONG           "--help"
-#define HELP_OPT_SHRT           "-h"
+#define HELP_OPT_LONG    "--help"
+#define HELP_OPT_SHRT    "-h"
 
 #define MAJOR 2
 #define MINOR 15
@@ -115,48 +116,6 @@ static void acquire_lockfile(void) {
   }
 }
 
-static bool get_config_file(char *restrict filename, char *restrict buffer, int buffer_size) {
-  char *xdg_home = getenv("XDG_CONFIG_HOME");
-  if (xdg_home && *xdg_home) {
-    snprintf(buffer, buffer_size, "%s/%s/%s", xdg_home, g_name, filename);
-    if (file_exists(buffer)) return true;
-  }
-
-  char *home = getenv("HOME");
-  if (!home) return false;
-
-  snprintf(buffer, buffer_size, "%s/.config/%s/%s", home, g_name, filename);
-  if (file_exists(buffer)) return true;
-
-  snprintf(buffer, buffer_size, "%s/.%s", home, filename);
-  return file_exists(buffer);
-}
-
-static void exec_config_file(void) {
-  if (!*g_config_file
-    && !get_config_file("sketchybarrc", g_config_file, sizeof(g_config_file))) {
-    printf("could not locate config file..\n");
-    return;
-  }
-
-  if (!file_exists(g_config_file)) {
-    printf("file '%s' does not exist..\n", g_config_file);
-    return;
-  }
-
-  setenv("CONFIG_DIR", dirname(g_config_file), 1);
-
-  if (!ensure_executable_permission(g_config_file)) {
-    printf("could not set the executable permission bit for '%s'\n", g_config_file);
-    return;
-  }
-
-  if (!fork_exec(g_config_file, NULL)) {
-    printf("failed to execute file '%s'\n", g_config_file);
-    return;
-  }
-}
-
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
 static inline void init_misc_settings(void) {
@@ -258,6 +217,8 @@ int main(int argc, char **argv) {
   initialize_media_events();
 
   exec_config_file();
+
+  begin_receiving_config_change_events();
   RunApplicationEventLoop();
   return 0;
 }