From 8eaf9e1d101d93c784b12902eb71d5b2985a6985 Mon Sep 17 00:00:00 2001
From: sewn <sewn@disroot.org>
Date: Sat, 12 Oct 2024 20:45:16 +0300
Subject: [PATCH] implement signals & turns

---
 config.def.h |  11 ++++--
 slstatus.c   | 108 ++++++++++++++++++++++++++++++++-------------------
 2 files changed, 75 insertions(+), 44 deletions(-)

diff --git a/config.def.h b/config.def.h
index d805331..a89127b 100644
--- a/config.def.h
+++ b/config.def.h
@@ -6,8 +6,8 @@ const unsigned int interval = 1000;
 /* text to show if no value can be retrieved */
 static const char unknown_str[] = "n/a";
 
-/* maximum output string length */
-#define MAXLEN 2048
+/* maximum command output length */
+#define CMDLEN 128
 
 /*
  * function            description                     argument (example)
@@ -64,6 +64,9 @@ static const char unknown_str[] = "n/a";
  * wifi_perc           WiFi signal in percent          interface name (wlan0)
  */
 static const struct arg args[] = {
-	/* function format          argument */
-	{ datetime, "%s",           "%F %T" },
+	/* function format          argument turn signal */
+	{ datetime, "%s",           "%F %T", 1,   -1 },
 };
+
+/* maximum output string length */
+#define MAXLEN CMDLEN * LEN(args)
diff --git a/slstatus.c b/slstatus.c
index fd31313..d5efd35 100644
--- a/slstatus.c
+++ b/slstatus.c
@@ -15,20 +15,19 @@ struct arg {
 	const char *(*func)(const char *);
 	const char *fmt;
 	const char *args;
+	unsigned int turn;
+	int signal;
 };
 
 char buf[1024];
-static volatile sig_atomic_t done;
+static int sflag = 0;
+static volatile sig_atomic_t done, upsigno;
 static Display *dpy;
 
 #include "config.h"
+#define MAXLEN CMDLEN * LEN(args)
 
-static void
-terminate(const int signo)
-{
-	if (signo != SIGUSR1)
-		done = 1;
-}
+static char statuses[LEN(args)][CMDLEN] = {0};
 
 static void
 difftimespec(struct timespec *res, struct timespec *a, struct timespec *b)
@@ -44,17 +43,61 @@ usage(void)
 	die("usage: %s [-v] [-s] [-1]", argv0);
 }
 
+static void
+printstatus(unsigned int iter)
+{
+	size_t i;
+	char status[MAXLEN];
+	const char *res;
+
+	for (i = 0; i < LEN(args); i++) {
+		if (!((!iter && !upsigno) || upsigno == SIGUSR1 ||
+			(!upsigno && args[i].turn > 0 && !(iter % args[i].turn)) ||
+			(args[i].signal >= 0 && upsigno - SIGRTMIN == args[i].signal)))
+			continue;
+
+		if (!(res = args[i].func(args[i].args)))
+			res = unknown_str;
+
+		if (esnprintf(statuses[i], sizeof(statuses[i]), args[i].fmt, res) < 0)
+			break;
+	}
+
+	status[0] = '\0';
+	for (i = 0; i < LEN(args); i++)
+		strcat(status, statuses[i]);
+	status[strlen(status)] = '\0';
+
+	if (sflag) {
+		puts(status);
+		fflush(stdout);
+		if (ferror(stdout))
+			die("puts:");
+	} else {
+		if (XStoreName(dpy, DefaultRootWindow(dpy), status) < 0)
+			die("XStoreName: Allocation failed");
+		XFlush(dpy);
+	}
+}
+
+
+static void
+sighandler(const int signo)
+{
+	if ((signo <= SIGRTMAX && signo >= SIGRTMIN) || signo == SIGUSR1)
+		upsigno = signo;
+	else
+		done = 1;
+}
+
 int
 main(int argc, char *argv[])
 {
 	struct sigaction act;
 	struct timespec start, current, diff, intspec, wait;
-	size_t i, len;
-	int sflag, ret;
-	char status[MAXLEN];
-	const char *res;
+	unsigned int iter = 0;
+	int i, ret;
 
-	sflag = 0;
 	ARGBEGIN {
 	case 'v':
 		die("slstatus-"VERSION);
@@ -72,11 +115,12 @@ main(int argc, char *argv[])
 		usage();
 
 	memset(&act, 0, sizeof(act));
-	act.sa_handler = terminate;
+	act.sa_handler = sighandler;
 	sigaction(SIGINT,  &act, NULL);
 	sigaction(SIGTERM, &act, NULL);
-	act.sa_flags |= SA_RESTART;
 	sigaction(SIGUSR1, &act, NULL);
+	for (i = SIGRTMIN; i <= SIGRTMAX; i++)
+		sigaction(i, &act, NULL);
 
 	if (!sflag && !(dpy = XOpenDisplay(NULL)))
 		die("XOpenDisplay: Failed to open display");
@@ -85,28 +129,7 @@ main(int argc, char *argv[])
 		if (clock_gettime(CLOCK_MONOTONIC, &start) < 0)
 			die("clock_gettime:");
 
-		status[0] = '\0';
-		for (i = len = 0; i < LEN(args); i++) {
-			if (!(res = args[i].func(args[i].args)))
-				res = unknown_str;
-
-			if ((ret = esnprintf(status + len, sizeof(status) - len,
-			                     args[i].fmt, res)) < 0)
-				break;
-
-			len += ret;
-		}
-
-		if (sflag) {
-			puts(status);
-			fflush(stdout);
-			if (ferror(stdout))
-				die("puts:");
-		} else {
-			if (XStoreName(dpy, DefaultRootWindow(dpy), status) < 0)
-				die("XStoreName: Allocation failed");
-			XFlush(dpy);
-		}
+		printstatus(iter++);
 
 		if (!done) {
 			if (clock_gettime(CLOCK_MONOTONIC, &current) < 0)
@@ -117,10 +140,15 @@ main(int argc, char *argv[])
 			intspec.tv_nsec = (interval % 1000) * 1E6;
 			difftimespec(&wait, &intspec, &diff);
 
-			if (wait.tv_sec >= 0 &&
-			    nanosleep(&wait, NULL) < 0 &&
-			    errno != EINTR)
-					die("nanosleep:");
+			do {
+					if (errno == EINTR) {
+						printstatus(0);
+						errno = upsigno = 0;
+					}
+					ret = nanosleep(&wait, &wait);
+			} while (wait.tv_sec >= 0 && ret < 0 && !done);
+			if (ret < 0 && errno != EINTR)
+				die("nanosleep:");
 		}
 	} while (!done);
 
-- 
2.46.2