From e0da9966255a9499085555ab43b5277730cf2e02 Mon Sep 17 00:00:00 2001
From: Justinas Grigas <dev@jstnas.com>
Date: Sun, 10 May 2026 15:25:31 +0100
Subject: [PATCH] xresources: runtime X Resources loading

---
 config.def.h | 20 +++++++++++++++++-
 dmenu.c      | 59 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 78 insertions(+), 1 deletion(-)

diff --git a/config.def.h b/config.def.h
index 1edb647..30daf5a 100644
--- a/config.def.h
+++ b/config.def.h
@@ -6,7 +6,8 @@ static int topbar = 1;                      /* -b  option; if 0, dmenu appears a
 static const char *fonts[] = {
 	"monospace:size=10"
 };
-static const char *prompt      = NULL;      /* -p  option; prompt to the left of input field */
+/* -p  option; prompt to the left of input field */
+static char *prompt = NULL;
 static const char *colors[SchemeLast][2] = {
 	/*     fg         bg       */
 	[SchemeNorm] = { "#bbbbbb", "#222222" },
@@ -21,3 +22,20 @@ static unsigned int lines      = 0;
  * for example: " /?\"&[]"
  */
 static const char worddelimiters[] = " ";
+
+/*
+ * Xresources preferences to load at startup
+ */
+static const XResPref resources[] = {
+	/* name                  type    address */
+	{ "dmenu.font",          STRING, &fonts[0] },
+	{ "dmenu.prompt",        STRING, &prompt },
+	{ "dmenu.foreground",    STRING, &colors[SchemeNorm][ColFg] },
+	{ "dmenu.background",    STRING, &colors[SchemeNorm][ColBg] },
+	{ "dmenu.foregroundSel", STRING, &colors[SchemeSel][ColFg] },
+	{ "dmenu.backgroundSel", STRING, &colors[SchemeSel][ColBg] },
+	{ "dmenu.foregroundOut", STRING, &colors[SchemeOut][ColFg] },
+	{ "dmenu.backgroundOut", STRING, &colors[SchemeOut][ColBg] },
+	{ "dmenu.topbar",        INTEGER, &topbar },
+	{ "dmenu.lines",         INTEGER, &lines },
+};
diff --git a/dmenu.c b/dmenu.c
index 363d19f..0ca41bc 100644
--- a/dmenu.c
+++ b/dmenu.c
@@ -11,6 +11,7 @@
 #include <X11/Xlib.h>
 #include <X11/Xatom.h>
 #include <X11/Xutil.h>
+#include <X11/Xresource.h>
 #ifdef XINERAMA
 #include <X11/extensions/Xinerama.h>
 #endif
@@ -52,6 +53,15 @@ static XIC xic;
 static Drw *drw;
 static Clr *scheme[SchemeLast];
 
+/* Xresources preferences */
+static XrmDatabase xrdb;
+enum XResType { STRING, INTEGER, FLOAT };
+typedef struct {
+	const char *name;
+	enum XResType type;
+	void *dst;
+} XResPref;
+
 #include "config.h"
 
 static int (*fstrncmp)(const char *, const char *, size_t) = strncmp;
@@ -107,6 +117,7 @@ cleanup(void)
 		free(items[i].text);
 	free(items);
 	drw_free(drw);
+	XrmDestroyDatabase(xrdb);
 	XSync(dpy, False);
 	XCloseDisplay(dpy);
 }
@@ -718,12 +729,60 @@ usage(void)
 	    "             [-nb color] [-nf color] [-sb color] [-sf color] [-w windowid]");
 }
 
+void
+xresload(const XResPref *resource)
+{
+	char *type;
+	XrmValue ret;
+
+	if (!XrmGetResource(xrdb, resource->name, NULL, &type, &ret))
+		return;
+	if (!ret.addr || strncmp(type, "String", sizeof("String")))
+		return;
+
+	switch (resource->type) {
+	case STRING:
+		*(char **)resource->dst = ret.addr;
+		break;
+	case INTEGER:
+		*(int *)resource->dst = strtoul(ret.addr, NULL, 10);
+		break;
+	case FLOAT:
+		*(float *)resource->dst = strtof(ret.addr, NULL);
+		break;
+	}
+}
+
+void
+xresupdate(void)
+{
+	Display *display;
+	char *resm;
+	const XResPref *p;
+
+	display = XOpenDisplay(NULL);
+	if (!display)
+		return;
+	resm = XResourceManagerString(display);
+	if (resm) {
+		xrdb = XrmGetStringDatabase(resm);
+		if (xrdb) {
+			for (p = resources; p < resources + LENGTH(resources); ++p)
+				xresload(p);
+		}
+	}
+	XCloseDisplay(display);
+}
+
 int
 main(int argc, char *argv[])
 {
 	XWindowAttributes wa;
 	int i, fast = 0;
 
+	XrmInitialize();
+	xresupdate();
+
 	for (i = 1; i < argc; i++)
 		/* these options take no arguments */
 		if (!strcmp(argv[i], "-v")) {      /* prints version information */
-- 
2.53.0