status: replace BSON with cJSON

Rather than relying on libbson to supply a convenient wrapper to
creating JSON fragments, instead use a dedicated/embeddable C API to
achieve the same result.

Although libbson might be fast, there simply isn't enough JSON being
used as an IPC mechanism for the overhead of using libbson.  By
overhead, this is referring to the fact that not every linux
distribution or BSD have packaged bson, or have a new enough version of
it.

Fixes #408

fvwm/builtins.c

@@ -27,6 +27,7 @@
 #include "libs/fvwm_x11.h"
 #include "libs/fvwmlib.h"
 #include "libs/fvwmsignal.h"
+#include "libs/cJSON.h"
 #include "libs/setpgrp.h"
 #include "libs/Grab.h"
 #include "libs/Parse.h"
@@ -129,86 +130,82 @@ static FILE *status_fp;
 void
 status_send(void)
 {
-	bson_t		 msg, screens;
-	bson_t		*desktops[256], *desk_doc[256], *individual_d[256];
-	int 		 i, d_count;
+	cJSON		*msg = NULL, *screens = NULL;
+	cJSON		*desk_doc[1024], *individual_d[1024];
+	int 		 m_count, d_count;
 	FvwmWindow	*fw_cur;
 	DesktopsInfo 	*di;
 	struct monitor	*m, *m_cur;
-	size_t		 json_len;
-	char		*as_json;
+	char		*as_json = NULL;
 
-	if (status_fp == NULL)
+	if (status_fp == NULL || !Scr.flags.are_windows_captured)
 		return;
 
-	memset(desktops, 0, sizeof(bson_t));
-	memset(individual_d, 0, sizeof(bson_t));
-	memset(desk_doc, 0, sizeof(bson_t));
+	memset(individual_d, 0, sizeof(cJSON));
+	memset(desk_doc, 0, sizeof(cJSON));
+
+	msg = cJSON_CreateObject();
 
 	m_cur = monitor_get_current();
 
-	bson_init(&msg);
-	BSON_APPEND_INT64(&msg, "version", 2);
-	BSON_APPEND_UTF8(&msg, "current_screen", m_cur->si->name);
-	BSON_APPEND_UTF8(&msg, "desktop_mode",
+	cJSON_AddNumberToObject(msg, "version", 2);
+	cJSON_AddStringToObject(msg, "current_screen", m_cur->si->name);
+	cJSON_AddStringToObject(msg, "desktop_mode",
 	    monitor_mode == MONITOR_TRACKING_G && is_tracking_shared ? "shared" :
 	    monitor_mode == MONITOR_TRACKING_G ? "global" :
 	    monitor_mode == MONITOR_TRACKING_M ? "per-monitor" :
 	    "unknown");
 
-	BSON_APPEND_DOCUMENT_BEGIN(&msg, "screens", &screens);
+	screens = cJSON_AddObjectToObject(msg, "screens");
 
-	d_count = 0;
+	d_count = 0, m_count = 0;
 	TAILQ_FOREACH(m, &monitor_q, entry) {
-		desktops[d_count] = bson_new();
-		desk_doc[d_count] = bson_new();
+		cJSON	*this_desktop;
+		if ((desk_doc[d_count] = cJSON_CreateObject()) == NULL)
+			goto out;
+
+		this_desktop = cJSON_AddObjectToObject(desk_doc[d_count],
+		    "desktops");
 
 		di = m->Desktops->next;
 		while (di != NULL) {
-			individual_d[d_count] = bson_new();
-			BSON_APPEND_INT64(individual_d[d_count], "number",
+			if ((individual_d[d_count] = cJSON_CreateObject()) == NULL)
+				goto out;
+			cJSON_AddNumberToObject(individual_d[d_count], "number",
 				di->desk);
-			BSON_APPEND_BOOL(individual_d[d_count], "is_current",
+			cJSON_AddBoolToObject(individual_d[d_count], "is_current",
 				di->desk == m->virtual_scr.CurrentDesk);
-			BSON_APPEND_BOOL(individual_d[d_count], "is_urgent",
+			cJSON_AddBoolToObject(individual_d[d_count], "is_urgent",
 				desk_get_fw_urgent(m, di->desk));
-			BSON_APPEND_INT64(individual_d[d_count],
+			cJSON_AddNumberToObject(individual_d[d_count],
 				"number_of_clients", desk_get_fw_count(m, di->desk));
-			BSON_APPEND_DOCUMENT(desktops[d_count], di->name,
-				individual_d[d_count]);
-			BSON_APPEND_DOCUMENT(desk_doc[d_count], "desktops",
-				desktops[d_count]);
+			cJSON_AddItemToObject(this_desktop, di->name, individual_d[d_count]);
 
 			di = di->next;
 		}
+
 		fw_cur = get_focus_window();
 		if (fw_cur != NULL && fw_cur->m == m) {
-			BSON_APPEND_UTF8(desk_doc[d_count], "current_client",
-				fw_cur->visible_name);
+			cJSON_AddStringToObject(desk_doc[d_count],
+			    "current_client", fw_cur->visible_name);
 		}
-		BSON_APPEND_DOCUMENT(&screens, m->si->name, desk_doc[d_count]);
+
+		cJSON_AddItemToObject(screens, m->si->name, desk_doc[d_count]);
+
 		d_count++;
+		m_count++;
 	}
-	bson_append_document_end(&msg, &screens);
-
-	if ((as_json = bson_as_relaxed_extended_json(&msg, &json_len)) == NULL)
+	if ((as_json = cJSON_PrintUnformatted(msg)) == NULL) {
 		goto out;
+	}
 
 	fflush(status_fp);
 	fprintf(status_fp, "%s\n", as_json);
 	fflush(status_fp);
 
 out:
-	bson_free(as_json);
-	for (i = 0; i < d_count; i++) {
-		if (desk_doc[i] != NULL)
-			bson_free(desk_doc[i]);
-		if (desktops[i] != NULL)
-			bson_free(desktops[i]);
-		if (individual_d[i] != NULL)
-			bson_free(individual_d[i]);
-	}
-	bson_destroy(&msg);
+	cJSON_free(as_json);
+	cJSON_Delete(msg);
 }
 
 #define PIPENAME "fvwm3.pipe"

fvwm/events.c

@@ -2559,7 +2559,6 @@ void HandleFocusIn(const evh_args_t *ea)
 				    fw->m->virtual_scr.CurrentDesk)
 					EWMH_SetCurrentDesktop(fw->m);
 			}
-			status_send();
 		}
 		last_focus_w = focus_w;
 		last_focus_fw = focus_fw;

libs/Makefile.am

@@ -16,6 +16,7 @@ libfvwm3_a_SOURCES = \
 	fsm.h ftime.h fvwm_sys_stat.h fvwm_x11.h fvwmlib.h fvwmrect.h fvwmsignal.h \
 	gravity.c gravity.h getpwuid.h lang-strings.h log.h modifiers.h queue.h \
 	safemalloc.h setpgrp.h strlcpy.h timeout.h vpacket.h wcontext.h wild.h \
+	cJSON.h \
 	\
 	BidiJoin.c Flocale.c PictureUtils.c FScreen.c Graphics.c \
 	PictureGraphics.c Bindings.c FlocaleCharset.c Parse.c \
@@ -26,7 +27,7 @@ libfvwm3_a_SOURCES = \
 	fvwmrect.c FRenderInit.c safemalloc.c  FBidi.c \
 	wild.c Grab.c Event.c ClientMsg.c setpgrp.c FShape.c \
 	FGettext.c Rectangles.c timeout.c flist.c charmap.c wcontext.c \
-	modifiers.c fsm.c FTips.c fio.c fvwmlib3.c strlcpy.c getpwuid.c
+	modifiers.c fsm.c FTips.c fio.c fvwmlib3.c strlcpy.c getpwuid.c cJSON.c
 
 libfvwm3_a_LIBADD = @LIBOBJS@