Restart by shortcut

src/config.def.h

@@ -34,6 +34,7 @@ static const Layout layouts[] = {
 static Key keys[] = {
 	// WM
 	{ MODKEY|ControlMask|ShiftMask, XK_q,            quit,           {0} },
+	{ MODKEY|ControlMask|ShiftMask, XK_r,            dorestart,      {0} },
 	// Monitor
 	{ MODKEY,                       XK_bracketleft,  focusmon,       {.i = -1 } },
 	{ MODKEY,                       XK_bracketright, focusmon,       {.i = +1 } },

src/dwm.c

@@ -164,6 +164,7 @@ static Monitor *createmon();
 static void detach(Client *c);
 static void detachstack(Client *c);
 static Monitor *dirtomon(int dir);
+static void dorestart(const Arg *arg);
 static void focus(Client *c);
 static void focusmon(const Arg *arg);
 static void focusstack(const Arg *arg);
@@ -650,6 +651,11 @@ Monitor *dirtomon(int dir)
 	return m;
 }
 
+void dorestart(__attribute__((unused)) const Arg *const arg)
+{
+	restart();
+}
+
 void focus(Client *c)
 {
 	if (!c || !ISVISIBLE(c))

src/main.c

@@ -10,9 +10,12 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/wait.h>
+#include <unistd.h>
 
 #define PROGRAM_NAME "polytreewm"
 
+static char *program_exe = NULL;
+
 static void signal_callback(int signo);
 
 static void logger(const char *level, const char *fmt, ...);
@@ -30,6 +33,10 @@ int main(int argc, char *argv[])
 		exit(EXIT_FAILURE);
 	}
 
+	if (!(program_exe = argv[0])) {
+		fatal("no program executable name");
+	}
+
 	if (!setlocale(LC_CTYPE, "") || !dwm_has_locale_support()) {
 		warning("no locale support");
 	}
@@ -44,6 +51,7 @@ int main(int argc, char *argv[])
 		struct sigaction action;
 		memset(&action, 0, sizeof(action));
 		action.sa_handler = signal_callback;
+
 		if (sigaction(SIGCHLD, &action, NULL) != 0) {
 			fatal_perror("can't install SIGCHLD handler");
 		}
@@ -54,10 +62,20 @@ int main(int argc, char *argv[])
 
 void signal_callback(const int signo)
 {
-	if (signo != SIGCHLD) return;
+	switch (signo) {
+	case SIGCHLD:
+		// Clean up any zombies immediately.
+		while (waitpid(-1, NULL, WNOHANG) > 0);
+		break;
+	}
+}
 
-	// Clean up any zombies immediately.
-	while (waitpid(-1, NULL, WNOHANG) > 0);
+void restart()
+{
+	info("restarting");
+	char *args[] = { program_exe, NULL };
+	execvp(program_exe, args);
+	fatal_perror("restart with `execvp' failed");
 }
 
 void logger(const char *const level, const char *const fmt, ...)
@@ -136,3 +154,11 @@ void warning_perror(const char *const fmt, ...)
 	logger_perror("WARN", fmt, ap);
 	va_end(ap);
 }
+
+void info(const char *const fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	logger("INFO", fmt, ap);
+	va_end(ap);
+}

src/main.h

@@ -9,5 +9,9 @@ void fatal_nodie(const char *fmt, ...);
 void fatal_perror_nodie(const char *fmt, ...);
 void warning(const char *fmt, ...);
 void warning_perror(const char *fmt, ...);
+void info(const char *fmt, ...);
+
+__attribute__((noreturn))
+void restart();
 
 #endif // _MAIN_H