stuff

 - fix memory leaks (except for those from libusb)
 - fix graceful shutdown
 - fix systemd weirdness

10 files changed, 220 insertions, 162 deletions

diff --git a/Makefile b/Makefile
index b17dec3..1e2e3bd 100644
--- a/Makefile
+++ b/Makefile
@@ -40,7 +40,7 @@ all: build
 include config.mk
 
 progs = freenect-server multipart-replace-http-server
-units = freenect-server-http.service freenect-server-http.socket freenect-server.service freenect-server@.socket
+units = freenect-server-http.service freenect-server-http.socket freenect-server.service
 
 build: $(addprefix src/,$(progs)) $(addprefix systemd/,$(units))
 .PHONY: build
@@ -53,12 +53,11 @@ CPPFLAGS += -MD -MF $(@D)/$(@F:%.o=.%.mk) -MP
 -include src/.*.mk
 
 # Dependencies that don't get figured out automatically
-src/freenect-server: src/util.o -lfreenect -lusb-1.0 -ljpeg
-src/multipart-replace-http-server: src/util.o src/wg.o src/multipart-replace.o -lpthread
+src/freenect-server: src/util.o -lsystemd -lfreenect -lusb-1.0 -ljpeg
+src/multipart-replace-http-server: src/util.o src/wg.o src/multipart-replace.o -lsystemd -lpthread
 systemd/freenect-server-http.service: .var.user .var.group .var.bindir
 systemd/freenect-server-http.socket: .var.httpstream
 systemd/freenect-server.service: .var.user .var.group .var.bindir
-systemd/freenect-server@.socket: .var.user .var.group
 
 # Rules to make things
 COPYING.GPL3:
diff --git a/src/freenect-server.c b/src/freenect-server.c
index a36701c..286455b 100644
--- a/src/freenect-server.c
+++ b/src/freenect-server.c
@@ -24,10 +24,13 @@
 #include <errno.h>
 #include <error.h>
 #include <inttypes.h>
+#include <stdbool.h>
 #include <stdio.h>
-#include <stdlib.h> /* atexit */
+#include <stdlib.h> /* atexit, EXIT_FAILURE */
 #include <unistd.h> /* dup2 */
 
+#include <systemd/sd-daemon.h>
+
 #include <libfreenect/libfreenect.h>
 #include <libusb-1.0/libusb.h>
 
@@ -35,10 +38,12 @@
 
 #include "util.h"
 
-FILE *depth_stream = NULL;
-FILE *video_stream = NULL;
-FILE *accel_stream = NULL;
-freenect_context *ctx;
+void stop(int sig);
+#define threaderror(stat, errnum, ...) do { \
+		error(0, errnum, __VA_ARGS__); \
+		exitcode = stat; \
+		stop(0); \
+	} while(0)
 
 struct mpjpg_encoder {
 	struct jpeg_error_mgr jpeg_encoder_err;
@@ -46,10 +51,17 @@ struct mpjpg_encoder {
 	unsigned char *jpeg_buf;
 	unsigned long jpeg_len;
 };
-
+
+int exitcode = 0;
+bool running = true;
+FILE *depth_stream = NULL;
+FILE *video_stream = NULL;
+FILE *accel_stream = NULL;
+freenect_context *ctx = NULL;
+freenect_device *dev = NULL;
 struct mpjpg_encoder depth_encoder;
 struct mpjpg_encoder video_encoder;
-
+
 void mpjpg_init(struct mpjpg_encoder *e) {
 	e->jpeg_encoder.err = jpeg_std_error(&e->jpeg_encoder_err);
 	jpeg_create_compress(&e->jpeg_encoder);
@@ -63,7 +75,12 @@ void mpjpg_init(struct mpjpg_encoder *e) {
 	jpeg_mem_dest(&e->jpeg_encoder, &e->jpeg_buf, &e->jpeg_len);
 }
 
-void write_imageframe(FILE *stream, struct mpjpg_encoder *e, JSAMPLE *data) {
+void mpjpg_destroy(struct mpjpg_encoder *e) {
+	jpeg_destroy_compress(&e->jpeg_encoder);
+	free(e->jpeg_buf);
+}
+
+void write_imageframe(const char *name, FILE *stream, struct mpjpg_encoder *e, JSAMPLE *data) {
 	JSAMPLE *row_pointers[480];
 	for (size_t i = 0; i < 480; i++)
 		row_pointers[i] = &data[i*640*3];
@@ -79,14 +96,14 @@ void write_imageframe(FILE *stream, struct mpjpg_encoder *e, JSAMPLE *data) {
 	            "Content-length: %lu\r\n"
 	            "\r\n",
 	            e->jpeg_len) < 1)
-		error(EXIT_FAILURE, ferror(stream), "writing header");
+		threaderror(EXIT_FAILURE, ferror(stream), "%s: writing header", name);
 	if (fwrite(e->jpeg_buf, e->jpeg_len, 1, stream) < 1)
-		error(EXIT_FAILURE, ferror(stream), "writing body");
+		threaderror(EXIT_FAILURE, ferror(stream), "%s: writing body", name);
 	if (fwrite("\r\n", 2, 1, stream) < 1)
-		error(EXIT_FAILURE, ferror(stream), "writing footer");
+		threaderror(EXIT_FAILURE, ferror(stream), "%s: writing footer", name);
 	fflush(stream);
 }
-
+
 void handle_accel(freenect_device *dev UNUSED, freenect_raw_tilt_state* data) {
 	double x, y, z, angle;
 	freenect_get_mks_accel(data, &x, &y, &z);
@@ -116,14 +133,16 @@ void handle_accel(freenect_device *dev UNUSED, freenect_raw_tilt_state* data) {
 	                 "	\"motor\": \"%s\" }\n",
 	                 x, y, z, angle, motor);
 	if (len < 0)
-		error(EXIT_FAILURE, errno, "asprintf");
-	fprintf(accel_stream,
+		threaderror(EXIT_FAILURE, errno, "accel.mjson: asprintf");
+	if (fprintf(accel_stream,
 	        "--ffserver\r\n"
 	        "Content-type: application/json\r\n"
 	        "Content-length: %d\r\n"
 	        "\r\n"
 	        "%s\r\n",
-	        len, json);
+	            len, json) < 0)
+		threaderror(EXIT_FAILURE, ferror(accel_stream), "accel.mjson: write");
+	free(json);
 	fflush(accel_stream);
 }
 
@@ -131,46 +150,28 @@ uint8_t depth_rgb[640*480*3];
 void handle_depth(freenect_device *dev, void *depth, uint32_t timestamp UNUSED) {
 	uint32_t size = freenect_get_current_depth_mode(dev).bytes;
 	if (size != 640*480*2)
-		error(EXIT_FAILURE, 0, "handle_depth: expected 640*480*2 byte frame, but got %"PRId32, size);
+		threaderror(EXIT_FAILURE, 0, "handle_depth: expected 640*480*2 byte frame, but got %"PRId32, size);
 	/* scale the 11-bit values into 8-bit values */
 	uint16_t *depth_grey = depth;
 	for (size_t i = 0; i < 640*480; i++)
 		depth_rgb[i*3+0] = depth_rgb[i*3+1] = depth_rgb[i*3+2] = (uint8_t)(depth_grey[i]*8.0/11.0);
 	/* write the image */
-	write_imageframe(depth_stream, &depth_encoder, depth_rgb);
+	write_imageframe("depth.mjpg", depth_stream, &depth_encoder, depth_rgb);
 }
 
 void handle_video(freenect_device *dev, void *rgb, uint32_t timestamp UNUSED) {
 	uint32_t size = freenect_get_current_video_mode(dev).bytes;
 	if (size != 640*480*3)
-		error(EXIT_FAILURE, 0, "handle_video: expected 640*480*3 byte frame, but got %"PRId32, size);
+		threaderror(EXIT_FAILURE, 0, "handle_video: expected 640*480*3 byte frame, but got %"PRId32, size);
 	/* write the image */
-	write_imageframe(video_stream, &video_encoder, rgb);
-}
-
-void print_mode(const char *name, freenect_frame_mode mode) {
-	/* This is just a courtesy function to let the user know the mode
-	   if it becomes a bother for maintainability just comment out the
-	   code in its body.  It will only break if struct entries go missing.
-	*/
-	printf("%s Mode: {%d, %d, {%d}, %d, %d, %d, %d, %d, %d, %d}\n", name,
-	       mode.reserved, (int)mode.resolution, (int)mode.video_format, mode.bytes, mode.width,
-	       mode.height, mode.data_bits_per_pixel, mode.padding_bits_per_pixel,
-	       mode.framerate, mode.is_valid);
+	write_imageframe("video.mjpg", video_stream, &video_encoder, rgb);
 }
-
-void cleanup() {
-	log("STOPPING=1");
-	if (ctx)
-		freenect_shutdown(ctx);
-	if (video_stream)
-		fclose(video_stream);
-	if (depth_stream)
-		fclose(depth_stream);
-	if (accel_stream)
-		fclose(accel_stream);
-	fflush(stderr);
-	sleep(5); /* work around systemd bug dropping log messages */
+
+void stop(int sig) {
+	if (sig != 0)
+		log("Caught %d", sig);
+	sd_notify(0, "STOPPING=1");
+	running = false;
 }
 
 FILE *xfopen(const char *path, const char *mode) {
@@ -194,10 +195,13 @@ void usage() {
 	printf("Usage: %s [-h] [-v video.mjpg|-V video_fd] [-d depth.mjpg|-D depth_fd] [-a accel.mjson|-A accel_fd]\n", program_invocation_name);
 }
 
+void cleanup(void);
+
 int main(int argc, char *argv[]) {
 	int res = 0;
-	freenect_device *dev;
 
+	mpjpg_init(&video_encoder);
+	mpjpg_init(&depth_encoder);
 	atexit(cleanup);
 
 	for (int i = 1; i < argc; i++) {
@@ -247,9 +251,6 @@ int main(int argc, char *argv[]) {
 		return EXIT_FAILURE;
 	}
 
-	mpjpg_init(&depth_encoder);
-	mpjpg_init(&video_encoder);
-
 	res = freenect_init(&ctx, 0);
 	if (res) {
 		error(EXIT_FAILURE, 0, "freenect_init: %s", libusb_strerror(res));
@@ -267,20 +268,26 @@ int main(int argc, char *argv[]) {
 	}
 
 	if (video_stream) {
-		print_mode("Video", freenect_find_video_mode(FREENECT_RESOLUTION_MEDIUM, FREENECT_VIDEO_RGB));
 		freenect_set_video_mode(dev, freenect_find_video_mode(FREENECT_RESOLUTION_MEDIUM, FREENECT_VIDEO_RGB));
 		freenect_start_video(dev);
 		freenect_set_video_callback(dev, handle_video);
 	}
 
 	if (depth_stream) {
-		print_mode("Depth", freenect_find_depth_mode(FREENECT_RESOLUTION_MEDIUM, FREENECT_DEPTH_11BIT));
 		freenect_set_depth_mode(dev, freenect_find_depth_mode(FREENECT_RESOLUTION_MEDIUM, FREENECT_DEPTH_11BIT));
 		freenect_start_depth(dev);
 		freenect_set_depth_callback(dev, handle_depth);
 	}
 
-	while (freenect_process_events(ctx) >= 0) {
+	signal(SIGPIPE, SIG_IGN);
+	signal(SIGTERM, stop);
+	signal(SIGQUIT, stop);
+	signal(SIGINT, stop);
+	while (running) {
+		if (freenect_process_events(ctx) < 0) {
+			stop(0);
+			continue;
+		}
 		if (accel_stream) {
 			freenect_raw_tilt_state* state;
 			freenect_update_tilt_state(dev);
@@ -288,8 +295,25 @@ int main(int argc, char *argv[]) {
 			handle_accel(dev, state);
 		}
 	}
+}
 
-	freenect_stop_depth(dev);
-	freenect_stop_video(dev);
-	freenect_close_device(dev);
+void cleanup() {
+	if (dev) {
+		freenect_stop_depth(dev);
+		freenect_stop_video(dev);
+		freenect_close_device(dev);
+	}
+	if (ctx)
+		freenect_shutdown(ctx);
+	if (video_stream)
+		fclose(video_stream);
+	if (depth_stream)
+		fclose(depth_stream);
+	if (accel_stream)
+		fclose(accel_stream);
+	mpjpg_destroy(&video_encoder);
+	mpjpg_destroy(&depth_encoder);
+	fflush(stderr);
+	if (sd_booted() > 0) sleep(5); /* work around systemd bug dropping log messages */
+	_exit(exitcode);
 }
diff --git a/src/multipart-replace-http-server.c b/src/multipart-replace-http-server.c
index 0541ff9..bc188b8 100644
--- a/src/multipart-replace-http-server.c
+++ b/src/multipart-replace-http-server.c
@@ -29,6 +29,8 @@
 #include <sys/un.h>
 #include <unistd.h>
 
+#include <systemd/sd-daemon.h>
+
 #include "util.h"
 #include "wg.h"
 #include "multipart-replace.h"
@@ -44,23 +46,28 @@ struct httpfile *filev = NULL;
 struct reader_thread_args {
 	struct multipart_replace_stream *stream;
 	int fd;
-	const char *filename;
-	const char *boundary;
+	char *filename;
+	char *boundary;
 };
 
-
+int exitcode = 0;
 bool running = true;
 int sock;
 struct wg wg;
 
 void stop(int sig) {
-	log("Caught %d", sig);
-	log("STOPPING=1");
+	if (sig != 0)
+		log("Caught %d", sig);
+	sd_notify(0, "STOPPING=1");
 	running = false;
 	close(sock);
 }
 
-#define threaderror(stat, errnum, ...) do { error(0, errnum, __VA_ARGS__); stop(0); } while(0)
+#define threaderror(stat, errnum, ...) do { \
+		error(0, errnum, __VA_ARGS__); \
+		exitcode = stat; \
+		stop(0); \
+	} while(0)
 
 void *reader_thread(void *args_anon) {
 	struct reader_thread_args *args = args_anon;
@@ -71,10 +78,12 @@ void *reader_thread(void *args_anon) {
 	pthread_setname_np(pthread_self(), name);
 	debug("starting thread: %s", name);
 
-	multipart_replace_reader(args->stream, args->fd, args->boundary);
-	sleep(5);
-	threaderror(EXIT_FAILURE, 0, "multipart_replace stream ended: %s", args->filename);
-	wg_sub(&wg, 1);
+	int ret = multipart_replace_reader(args->stream, args->fd, args->boundary);
+	threaderror(ret, 0, "multipart_replace stream ended: %s", args->filename);
+	free(args->filename);
+	free(args->boundary);
+	free(args);
+	wg_sub(&wg);
 	return NULL;
 }
 
@@ -83,9 +92,9 @@ void start_multipart_replace_reader(struct multipart_replace_stream *s, int fd,
 	args->stream = s;
 	args->fd = fd;
 	args->filename = strdup(filename);
-	args->boundary = boundary;
+	args->boundary = strdup(boundary);
 	pthread_t thread;
-	wg_add(&wg, 1);
+	wg_add(&wg);
 	pthread_create(&thread, NULL, reader_thread, args);
 }
 
@@ -132,13 +141,13 @@ void connection_handler(int fd) {
 		        "HTTP/1.1 405 Method Not Allowed\r\n"
 		        "Allow: GET\r\n"
 		        "\r\n");
-		close(fd);
+		fclose(netstream);
 		return;
 	}
 	char *version = &line_buf[4];
 	char *path = strsep(&version, " ");
 	if (strcmp(version, "HTTP/1.1\r\n") != 0 && strcmp(version, "HTTP/1.0\r\n")) {
-		close(fd);
+		fclose(netstream);
 		return;
 	}
 	path = strdupa(path);
@@ -146,6 +155,7 @@ void connection_handler(int fd) {
 	/* run through the rest of the headers */
 	while (strcmp(line_buf, "\r\n") != 0 && line_len >= 0)
 		line_len = getline(&line_buf, &line_cap, netstream);
+	free(line_buf);
 
 	if (strcmp(path, "/") == 0) {
 		log("200 %s", path);
@@ -167,7 +177,7 @@ void connection_handler(int fd) {
 		        "  </ul>\n"
 		        "</body>\n"
 		        "</html>\n");
-		close(fd);
+		fclose(netstream);
 		return;
 	}
 	struct multipart_replace_stream *vidstream = file_get(path);
@@ -187,7 +197,7 @@ void connection_handler(int fd) {
 	        "\r\n",
 	        boundary);
 	multipart_replace_writer(vidstream, fd, boundary);
-	close(fd);
+	fclose(netstream);
 }
 
 void *connection_thread(void *arg_anon) {
@@ -196,7 +206,7 @@ void *connection_thread(void *arg_anon) {
 	log("Connection %d opened", fd);
 	connection_handler(fd);
 	log("Connection %d closed", fd);
-	wg_sub(&wg, 1);
+	wg_sub(&wg);
 	return NULL;
 }
 
@@ -323,7 +333,8 @@ void usage() {
 
 void cleanup() {
 	fflush(stderr);
-	sleep(5); /* work around systemd bug dropping log messages */
+	if (sd_booted() > 0) sleep(5); /* work around systemd bug dropping log messages */
+	_exit(exitcode);
 }
 
 pthread_t main_thread;
@@ -372,12 +383,14 @@ int main(int argc, char *argv[]) {
 		if (conn < 0)
 			continue;
 		pthread_t thread;
-		wg_add(&wg, 1);
+		wg_add(&wg);
 		pthread_create(&thread, NULL, connection_thread, (void*)(intptr_t)conn);
 	}
 	wg_wait(&wg);
-	for (size_t i = 0; i < filec; i++)
+	for (size_t i = 0; i < filec; i++) {
 		destroy_multipart_replace_stream(filev[i].stream);
+		free(filev[i].stream);
+	}
 	free(filev);
 	return 0;
 }
diff --git a/src/multipart-replace.c b/src/multipart-replace.c
index b1fe662..fa893f2 100644
--- a/src/multipart-replace.c
+++ b/src/multipart-replace.c
@@ -27,7 +27,25 @@
 #include "multipart-replace.h"
 #include "util.h"
 
-#define error(stat, errnum, ...) do { error(0, errnum, __VA_ARGS__); goto end; } while(0)
+#define error(stat, errnum, ...) do { \
+		error(0, errnum, __VA_ARGS__); \
+		ret = stat; \
+		goto end; \
+	} while(0)
+#define stdioerror(stream, name) do {	  \
+		if (feof(stream)) { \
+			error(0, 0, "%s: EOF", name); \
+		} else { \
+			int err = ferror(stream); \
+			if (err != 0) { \
+				error(0, err, "%s", name); \
+			} else { \
+				error(0, errno, "%s: umm... what?  Not EOF, but also not error.  Here's errno", name); \
+			} \
+			ret = EXIT_FAILURE; \
+		} \
+		goto end; \
+	} while(0)
 
 static
 char *boundary_line(const char *old) {
@@ -57,7 +75,8 @@ ssize_t safe_atoi(char *str) {
 	return atoi(str);
 }
 
-void multipart_replace_reader(struct multipart_replace_stream *s, int fd, const char *_boundary) {
+int multipart_replace_reader(struct multipart_replace_stream *s, int fd, const char *_boundary) {
+	int ret = 0;
 	FILE *stream = fdopen(fd, "r");
 	char *boundary = boundary_line(_boundary);
 
@@ -66,33 +85,23 @@ void multipart_replace_reader(struct multipart_replace_stream *s, int fd, const
 	ssize_t line_len = 0;
 	ssize_t content_length = -1;
 
-	bool first = true;
 	while (running) {
 		content_length = -1;
 		/* scan for the first non-empty line */
 		do {
 			line_len = getline(&line_buf, &line_cap, stream);
 			if (line_len < 0)
-				error(EXIT_FAILURE, ferror(stream), "source hung up");
+				stdioerror(stream, "src");
 		} while (strcmp(line_buf, "\r\n") == 0);
 		/* make sure it matches the boundary separator */
-		if (first) {
-			while (strcmp(line_buf, boundary) != 0) {
-				line_len = getline(&line_buf, &line_cap, stream);
-				if (line_len < 0)
-					error(EXIT_FAILURE, ferror(stream), "source hung up");
-			}
-			first = false;
-		} else {
-			if (strcmp(line_buf, boundary) != 0)
-				error(EXIT_FAILURE, 0, "line does not match boundary: \"%s\"", line_buf);
-		}
+		if (strcmp(line_buf, boundary) != 0)
+			error(EXIT_FAILURE, 0, "line does not match boundary: \"%s\"", line_buf);
 		/* read the frame header (MIME headers) */
 		s->back->len = 0;
 		do {
 			line_len = getline(&line_buf, &line_cap, stream);
 			if (line_len < 0)
-				error(EXIT_FAILURE, ferror(stream), "source hung up");
+				stdioerror(stream, "src");
 			/* append the line to the frame contents */
 			if ((ssize_t)s->back->cap < s->back->len + line_len)
 				s->back->buf = xrealloc(s->back->buf, s->back->cap = s->back->len + line_len);
@@ -110,7 +119,7 @@ void multipart_replace_reader(struct multipart_replace_stream *s, int fd, const
 		if ((ssize_t)s->back->cap < s->back->len + content_length)
 			s->back->buf = xrealloc(s->back->buf, s->back->cap = s->back->len + content_length);
 		if (fread(&s->back->buf[s->back->len], content_length, 1, stream) != 1)
-			error(EXIT_FALURE, ferror(stream), "fread(%zd)", s->back->len);
+			stdioerror(stream, "src");
 		s->back->len += content_length;
 
 		/* swap the frames */
@@ -123,10 +132,13 @@ void multipart_replace_reader(struct multipart_replace_stream *s, int fd, const
 	}
  end:
 	free(boundary);
+	free(line_buf);
 	fclose(stream);
+	return ret;
 }
 
-void multipart_replace_writer(struct multipart_replace_stream *s, int fd, const char *_boundary) {
+int multipart_replace_writer(struct multipart_replace_stream *s, int fd, const char *_boundary) {
+	int ret = 0;
 	FILE *stream = fdopen(fd, "w");
 	struct frame myframe = { 0 };
 	long lastframe = 0;
@@ -145,12 +157,12 @@ void multipart_replace_writer(struct multipart_replace_stream *s, int fd, const
 
 		/* send the frame to the client */
 		if (fwrite(boundary, boundary_len, 1, stream) < 1)
-			error(EXIT_FAILURE, ferror(stream), "fwrite(boundary)");
+			stdioerror(stream, "dst <- boundary");
 		if (fwrite(myframe.buf, myframe.len, 1, stream) < 1)
-			error(EXIT_FAILURE, ferror(stream), "fwrite(frame.buf)");
+			stdioerror(stream, "dst <- frame");
 		/* send a blank line for pleasantness */
 		if (fwrite("\r\n", 2, 1, stream) < 1)
-			error(EXIT_FAILURE, ferror(stream), "fwrite(\"\\r\\n\")");
+			stdioerror(stream, "dst <- nl");
 		fflush(stream);
 
 		/* poll until there's a new frame */
@@ -166,6 +178,7 @@ void multipart_replace_writer(struct multipart_replace_stream *s, int fd, const
 	free(boundary);
 	free(myframe.buf);
 	fclose(stream);
+	return ret;
 }
 
 void init_multipart_replace_stream(struct multipart_replace_stream *s) {
diff --git a/src/multipart-replace.h b/src/multipart-replace.h
index 502cecc..e4cced0 100644
--- a/src/multipart-replace.h
+++ b/src/multipart-replace.h
@@ -34,8 +34,8 @@ struct multipart_replace_stream {
 	long framecount;
 };
 
-void multipart_replace_reader(struct multipart_replace_stream *s, int fd, const char *boundary);
-void multipart_replace_writer(struct multipart_replace_stream *s, int fd, const char *boundary);
+int multipart_replace_reader(struct multipart_replace_stream *s, int fd, const char *boundary);
+int multipart_replace_writer(struct multipart_replace_stream *s, int fd, const char *boundary);
 void init_multipart_replace_stream(struct multipart_replace_stream *s);
 void destroy_multipart_replace_stream(struct multipart_replace_stream *s);
 
diff --git a/src/wg.c b/src/wg.c
index c326f53..4e673b4 100644
--- a/src/wg.c
+++ b/src/wg.c
@@ -26,37 +26,75 @@
 
 /* pthread_cond_t is overly complicated. Just use a self-pipe. */
 
+static
+void *wg_gc(void *wg_anon) {
+	struct wg *wg = wg_anon;
+
+	pthread_t thread;
+	while (1) {
+		ssize_t r = read(wg->fd_threads[0], &thread, sizeof(thread));
+		if (r < 0) {
+			if (errno == EINTR)
+				continue;
+			error(EXIT_FAILURE, errno, "wg_gc: read");
+		} else if ((size_t)r < sizeof(thread)) {
+			error(EXIT_FAILURE, 0, "wg_gc: read: only read %zd/%zu", r, sizeof(thread));
+		}
+
+		pthread_join(thread, NULL);
+
+		int p;
+		if ((p = pthread_mutex_lock(&wg->lock)) != 0)
+			error(EXIT_FAILURE, p, "wg_gc: pthread_mutex_lock");
+		wg->count--;
+		if (wg->count == 0) {
+			if ((p = pthread_mutex_unlock(&wg->lock)) != 0)
+				error(EXIT_FAILURE, p, "wg_gc: pthread_mutex_unlock");
+			return NULL;
+		}
+		if ((p = pthread_mutex_unlock(&wg->lock)) != 0)
+			error(EXIT_FAILURE, p, "wg_gc: pthread_mutex_unlock");
+	}
+}
+
 void wg_init(struct wg *wg) {
 	wg->count = 0;
-	pthread_mutex_init(&wg->lock, NULL);
-	int fds[2];
-	if (pipe(fds) != 0)
-		error(EXIT_FAILURE, errno, "pipe");
-	wg->fd_wait = fds[0];
-	wg->fd_signal = fds[1];
+	int r;
+	if ((r = pthread_mutex_init(&wg->lock, NULL)) != 0)
+		error(EXIT_FAILURE, r, "wg_init: pthread_mutex_init");
+	if (pipe(wg->fd_threads) != 0)
+		error(EXIT_FAILURE, errno, "wg_init: pipe");
+	if ((r = pthread_create(&wg->gc, NULL, wg_gc, (void*)wg)) != 0)
+		error(EXIT_FAILURE, r, "wg_init: pthread_create");
 }
 
-void wg_add(struct wg *wg, unsigned int n) {
-	pthread_mutex_lock(&wg->lock);
-	wg->count += n;
-	pthread_mutex_unlock(&wg->lock);
+void wg_add(struct wg *wg) {
+	int r;
+	if ((r = pthread_mutex_lock(&wg->lock)) != 0)
+		error(EXIT_FAILURE, r, "wg_add: pthread_mutex_lock");
+	wg->count++;
+	if ((r = pthread_mutex_unlock(&wg->lock)) != 0)
+		error(EXIT_FAILURE, r, "wg_add: pthread_mutex_unlock");
 }
 
-void wg_sub(struct wg *wg, unsigned int n) {
-	pthread_mutex_lock(&wg->lock);
-	wg->count -= n;
-	if (wg->count == 0)
-		if (write(wg->fd_signal, " ", 1) < 1)
-			error(EXIT_FAILURE, errno, "write");
-	pthread_mutex_unlock(&wg->lock);
+void wg_sub(struct wg *wg) {
+	pthread_t thread = pthread_self();
+	ssize_t r = write(wg->fd_threads[1], &thread, sizeof(thread));
+	if (r < 0) {
+		error(EXIT_FAILURE, errno, "wg_sub: write");
+	} else if ((size_t)r < sizeof(thread)) {
+		error(EXIT_FAILURE, 0, "wg_sub: only wrote %zd/%zu", r, sizeof(thread));
+	}
 }
 
 void wg_wait(struct wg *wg) {
-	char b;
- retry:
-	if (read(wg->fd_wait, &b, 1) == -1) {
-		if (errno == EINTR)
-			goto retry;
-		error(EXIT_FAILURE, errno, "wg_wait");
-	}
+	int r;
+	if ((r = pthread_join(wg->gc, NULL)) != 0)
+		error(EXIT_FAILURE, r, "wg_wait: pthread_join");
+	if (close(wg->fd_threads[1]) != 0)
+		error(EXIT_FAILURE, errno, "wg_wait: close(fd_threads[1])");
+	if (close(wg->fd_threads[0]) != 0)
+		error(EXIT_FAILURE, errno, "wg_wait: close(fd_threads[0])");
+	if ((r = pthread_mutex_destroy(&wg->lock)) != 0)
+		error(EXIT_FAILURE, r, "wg_wait: pthread_mutex_destroy");
 }
diff --git a/src/wg.h b/src/wg.h
index c7efcb2..b2eb4c4 100644
--- a/src/wg.h
+++ b/src/wg.h
@@ -21,18 +21,17 @@
 
 #include <pthread.h>
 
-/* Thread management tools modeled on https://golang.org/pkg/sync/#WaitGroup */
-
-/* pthread_cond_t is overly complicated. Just use a self-pipe. */
+/* When you call wg_wait, the waitgroup is destroyed.  You must
+ * re-wg_init it if you want to reuse it. */
 
 struct wg {
 	int count;
 	pthread_mutex_t lock;
-	int fd_wait;
-	int fd_signal;
+	int fd_threads[2];
+	pthread_t gc;
 };
 
 void wg_init(struct wg *);
-void wg_add(struct wg *, unsigned int);
-void wg_sub(struct wg *, unsigned int);
+void wg_add(struct wg *);
+void wg_sub(struct wg *);
 void wg_wait(struct wg*);
diff --git a/systemd/freenect-server-http.service.in b/systemd/freenect-server-http.service.in
index 8bb5b44..2aa97d7 100644
--- a/systemd/freenect-server-http.service.in
+++ b/systemd/freenect-server-http.service.in
@@ -17,7 +17,6 @@
 Description=Kinect HTTP media streamer
 After=network.target
 Requires=freenect-server-http.socket freenect-server.service
-PartOf=freenect-server.service
 After=freenect-server.service
 
 [Service]
diff --git a/systemd/freenect-server.service.in b/systemd/freenect-server.service.in
index c6a719e..c0417b6 100644
--- a/systemd/freenect-server.service.in
+++ b/systemd/freenect-server.service.in
@@ -15,13 +15,11 @@
 
 [Unit]
 Description=Kinect media streamer backend
-After=network.target
-Requires=freenect-server@accel.mjson.socket freenect-server@depth.mjpg.socket freenect-server@video.mjpg.socket
 
 [Service]
 Type=simple
 User=@user@
 Group=@group@
-ExecStart=@bindir@/freenect-server -V systemd:freenect-server@video.mjpg.socket -D systemd:freenect-server@depth.mjpg.socket -A systemd:freenect-server@accel.mjson.socket
-
-Restart=always
+RuntimeDirectory=freenect-server
+ExecStartPre=/usr/bin/mkfifo /run/freenect-server/video.mjpg /run/freenect-server/depth.mjpg /run/freenect-server/accel.mjson
+ExecStart=@bindir@/freenect-server -v /run/freenect-server/video.mjpg -d /run/freenect-server/depth.mjpg -a /run/freenect-server/accel.mjson
diff --git a/systemd/freenect-server@.socket.in b/systemd/freenect-server@.socket.in
deleted file mode 100644
index 8be3205..0000000
--- a/systemd/freenect-server@.socket.in
+++ /dev/null
@@ -1,25 +0,0 @@
-# Copyright (C) 2016  Luke Shumaker
-#
-# This program is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-[Unit]
-Description=Kinect media streamer backend %I stream
-After=network.target
-
-[Socket]
-SocketUser=@user@
-SocketGroup=@group@
-ListenFIFO=/run/freenect-server/%I
-Service=freenect-server.service
-RemoveOnStop=true
\ No newline at end of file