Add support for SIGINT and SIGHUP

Signed-off-by: Mattias Andrée <m@maandree.se>

1 files changed, 179 insertions, 12 deletions

diff --git a/radharc.c b/radharc.c
index 37179b7..12f5ce8 100644
--- a/radharc.c
+++ b/radharc.c
@@ -3,6 +3,7 @@
 
 #include <sys/timerfd.h>
 #include <errno.h>
+#include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
@@ -91,6 +92,27 @@ static int dflag = 0;
  */
 static int xflag = 0;
 
+
+/**
+ * If 0, SIGINT has not been received,
+ * if 1, SIGINT has been received once as the effect
+ *       should be faded out and then the effect should
+ *       be removed and the program terminated,
+ * if 2, SIGINT has been received at least twice and
+ *       the effect should be removed immediately
+ *       and the program terminated
+ */
+static volatile sig_atomic_t sigint_received = 0;
+
+/**
+ * If 0, SIGHUP has not been received,
+ * if 1, SIGHUP has been received and the effect
+ *       shall be made `LIBCOOPGAMMA_UNTIL_REMOVAL` and
+ *       the program terminated
+ */
+static volatile sig_atomic_t sighup_received = 0;
+
+
 /**
  * Print usage information and exit
  */
@@ -104,6 +126,7 @@ usage(void)
 	exit(1);
 }
 
+
 /**
  * Parse a non-negative double encoded as a string
  * 
@@ -124,6 +147,7 @@ parse_double(double *out, const char *str)
 	return 0;
 }
 
+
 /**
  * Handle a command line option
  * 
@@ -209,6 +233,7 @@ handle_opt(char *opt, char *arg)
 	return 0;
 }
 
+
 /**
  * This function is called after the last
  * call to `handle_opt`
@@ -228,6 +253,7 @@ handle_args(int argc, char *argv[], char *prio)
 	(void) prio;
 }
 
+
 /**
  * Fill a filter
  * 
@@ -254,6 +280,7 @@ LIST_DEPTHS
 	}
 }
 
+
 /**
  * Set the gamma ramps
  * 
@@ -273,15 +300,19 @@ set_ramps(double red, double green, double blue)
 
 	libclut_model_standard_to_linear(&red, &green, &blue);
 	for (i = 0, r = 1; i < filters_n; i++) {
-		if (!(crtc_updates[i].master) || !(crtc_info[crtc_updates[i].crtc].supported))
+		if (!crtc_updates[i].master || !crtc_info[crtc_updates[i].crtc].supported)
 			continue;
-		fill_filter(&(crtc_updates[i].filter), red, green, blue);
-		r = update_filter(i, 0);
+		fill_filter(&crtc_updates[i].filter, red, green, blue);
+		do {
+			r = update_filter(i, 0);
+		} while (r == -1 && errno == EINTR);
 		if (r == -2 || (r == -1 && errno != EAGAIN))
 			return r;
 		if (crtc_updates[i].slaves) {
 			for (j = 0; crtc_updates[i].slaves[j] != 0; j++) {
-				r = update_filter(crtc_updates[i].slaves[j], 0);
+				do {
+					r = update_filter(crtc_updates[i].slaves[j], 0);
+				} while (r == -1 && errno == EINTR);
 				if (r == -2 || (r == -1 && errno != EAGAIN))
 					return r;
 			}
@@ -290,11 +321,13 @@ set_ramps(double red, double green, double blue)
 
 	while (r != 1)
 		if ((r = synchronise(-1)) < 0)
-			return r;
+			if (r != -1 || errno != EINTR)
+				return r;
 
 	return 0;
 }
 
+
 /**
  * Get the colour temperature for the current time
  * 
@@ -321,6 +354,32 @@ get_temperature(double *tp)
 
 
 /**
+ * Called when SIGINT is received
+ * 
+ * @param  sig  Always `SIGINT`
+ */
+static void
+sigint_handler(int sig)
+{
+	(void) sig;
+	sigint_received = sigint_received ? 2 : 1;
+}
+
+
+/**
+ * Called when SIGHUP is received
+ * 
+ * @param  sig  Always `SIGHUP`
+ */
+static void
+sighup_handler(int sig)
+{
+	(void) sig;
+	sighup_received = 1;
+}
+
+
+/**
  * The main function for the program-specific code
  * 
  * @return  0: Success
@@ -333,8 +392,20 @@ start(void)
 {
 	int r, tfd;
 	size_t i;
-	double temperature, red, green, blue;
+	double target_temperature;
+	long int original_temperature;
+	long int current_temperature = 6500;
+	double red = 1, green = 1, blue = 1;
 	uint64_t overrun;
+	struct sigaction sa;
+	struct timespec sleep_timeout;
+	const char *side;
+
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = &sigint_handler;
+	sigaction(SIGINT, &sa, NULL);
+	sa.sa_handler = &sighup_handler;
+	sigaction(SIGHUP, &sa, NULL);
 
 	if (xflag)
 		for (i = 0; i < filters_n; i++)
@@ -366,16 +437,26 @@ start(void)
 		return -1;
 
 	for (i = 0; i < (size_t)fade_in_cs;) {
+		if (sigint_received) {
+			double cs = (double)i / fade_in_cs * fade_out_cs + 0.5;
+			fade_out_cs = (unsigned long int)cs;
+			goto fade_out_have_timer;
+		}
+
 		if (i % 600 == 0)
-			if ((r = get_temperature(&temperature)) < 0)
+			if ((r = get_temperature(&target_temperature)) < 0)
 				return r;
-		if (libred_get_colour((long int)(6500 - (6500 - temperature) * i / fade_in_cs), &red, &green, &blue))
+		current_temperature = (long int)(6500 - (6500 - target_temperature) * i / fade_in_cs);
+		if (libred_get_colour(current_temperature, &red, &green, &blue))
 			return -1;
 		if ((r = set_ramps(red, green, blue)) < 0)
 			return r;
 
-		if (read(tfd, &overrun, sizeof(overrun)) != sizeof(overrun))
+		while (read(tfd, &overrun, sizeof(overrun)) != sizeof(overrun)) {
+			if (errno == EINTR)
+				continue;
 			return -1;
+		}
 		if (overrun > fade_in_cs - i)
 			overrun = fade_in_cs - i;
 		i += overrun;
@@ -385,9 +466,19 @@ start(void)
 
 no_fade_in:
 	for (;;) {
-		if ((r = get_temperature(&temperature)) < 0)
+		if (sigint_received)
+			goto fade_out;
+
+		if (sighup_received) {
+			for (i = 0; i < filters_n; i++)
+				crtc_updates[i].filter.lifespan = LIBCOOPGAMMA_UNTIL_REMOVAL;
+			return set_ramps(red, green, blue);
+		}
+
+		if ((r = get_temperature(&target_temperature)) < 0)
 			return r;
-		if (libred_get_colour((long int)temperature, &red, &green, &blue))
+		current_temperature = (long int)target_temperature;
+		if (libred_get_colour(current_temperature, &red, &green, &blue))
 			return -1;
 		if ((r = set_ramps(red, green, blue)) < 0)
 			return r;
@@ -395,6 +486,82 @@ no_fade_in:
 		if (!dflag)
 			return 0;
 
-		sleep(6);
+		sleep_timeout.tv_sec = 6;
+		sleep_timeout.tv_nsec = 0;
+		while ((errno = clock_nanosleep(CLOCK_BOOTTIME, 0, &sleep_timeout, &sleep_timeout))) {
+			if (errno == EINTR) {
+				if (sigint_received || sighup_received)
+					break;
+				continue;
+			}
+			return -1;
+		}
+	}
+
+fade_out:
+	tfd = timerfd_create(CLOCK_MONOTONIC, 0);
+	if (tfd < 0)
+		goto fade_out_fail;
+	if (timerfd_settime(tfd, 0, &(struct itimerspec){{0, 10000000L}, {0, 10000000L}}, NULL))
+		goto fade_out_fail;
+
+fade_out_have_timer:
+	original_temperature = current_temperature;
+	for (i = 0; i < (size_t)fade_out_cs;) {
+		if (sigint_received > 1)
+			break;
+
+		current_temperature = original_temperature + (double)(6500 - original_temperature) * i / fade_out_cs;
+		if (libred_get_colour(current_temperature, &red, &green, &blue))
+			goto fade_out_fail;
+		if ((r = set_ramps(red, green, blue)) < 0)
+			goto fade_out_fail_use_r;
+
+		while (read(tfd, &overrun, sizeof(overrun)) != sizeof(overrun)) {
+			if (errno == EINTR)
+				continue;
+			goto fade_out_fail;
+		}
+		if (overrun > fade_in_cs - i)
+			overrun = fade_in_cs - i;
+		i += overrun;
 	}
+
+	close(tfd);
+
+	for (i = 0; i < filters_n; i++)
+		crtc_updates[i].filter.lifespan = LIBCOOPGAMMA_REMOVE;
+	return set_ramps(1, 1, 1);
+
+fade_out_fail_use_r:
+	switch (r) {
+	case -1:
+	fade_out_fail:
+		perror(argv0);
+		break;
+	case -2:
+		side = cg.error.server_side ? "server" : "client";
+		if (cg.error.custom) {
+			if (cg.error.number && cg.error.description) {
+				fprintf(stderr, "%s: %s-side error number %" PRIu64 ": %s\n",
+					argv0, side, cg.error.number, cg.error.description);
+			} else if (cg.error.number) {
+				fprintf(stderr, "%s: %s-side error number %" PRIu64 "\n", argv0, side, cg.error.number);
+			} else if (cg.error.description) {
+				fprintf(stderr, "%s: %s-side error: %s\n", argv0, side, cg.error.description);
+			}
+		} else if (cg.error.description) {
+			fprintf(stderr, "%s: %s-side error: %s\n", argv0, side, cg.error.description);
+		} else {
+			fprintf(stderr, "%s: %s-side error: %s\n", argv0, side, strerror((int)cg.error.number));
+		}
+		break;
+	default:
+		break;
+	}
+
+	for (i = 0; i < filters_n; i++)
+		crtc_updates[i].filter.lifespan = LIBCOOPGAMMA_REMOVE;
+	r = set_ramps(1, 1, 1);
+	return r ? r : -3;
 }