Bump version: 0.59 → 0.60

.bumpversion.cfg

@@ -1,7 +1,7 @@
 [bumpversion]
 commit = True
 tag = True
-current_version = 0.56
+current_version = 0.60
 parse = (?P<major>\d+)\.(?P<minor>\d+)(\.(?P<patch>\d+)(\-(?P<release>[a-z]+))?)?
 serialize = 
 	{major}.{minor}

Makefile

@@ -7,7 +7,7 @@ CC ?= gcc
 
 # =====
 LIBS = -lm -ljpeg -pthread -levent -levent_pthreads -luuid
-override CFLAGS += -c -std=c99 -Wall -Wextra -D_GNU_SOURCE
+override CFLAGS += -c -std=c11 -Wall -Wextra -D_GNU_SOURCE
 SOURCES = $(shell ls src/*.c src/encoders/cpu/*.c src/encoders/hw/*.c)
 PROG = ustreamer
 

PKGBUILD

@@ -3,7 +3,7 @@
 
 
 pkgname=ustreamer
-pkgver=0.56
+pkgver=0.60
 pkgrel=1
 pkgdesc="Lightweight and fast MJPG-HTTP streamer"
 url="https://github.com/pi-kvm/ustreamer"

README.md

@@ -56,6 +56,8 @@ The recommended way of running µStreamer with [Auvidea B101](https://www.raspbe
 $ ./ustreamer \
     --format=uyvy \ # Device input format
     --encoder=omx \ # Hardware encoding with OpenMAX
+    --workers=3 \ # Maximum workers for OpenMAX
+    --persistent \ # Don't re-initialize device on timeout (for example when HDMI cable was disconnected)
     --dv-timings \ # Use DV-timings
     --drop-same-frames=30 # Save that traffic
 ```

README.ru.md

@@ -56,6 +56,8 @@ $ ./ustreamer --help
 $ ./ustreamer \
     --format=uyvy \ # Настройка входного формата устройства
     --encoder=omx \ # Использование аппаратного кодирования с помощью OpenMAX
+    --workers=3 \ # Максимум воркеров для OpenMAX
+    --persistent \ # Не переинициализировать устройство при таймауте (например, когда был отключен HDMI-кабель)
     --dv-timings \ # Включение DV-таймингов
     --drop-same-frames=30 # Экономим трафик
 ```

src/config.h

@@ -22,4 +22,4 @@
 
 #pragma once
 
-#define VERSION "0.56"
+#define VERSION "0.60"

src/device.c

@@ -95,7 +95,7 @@ struct device_t *device_init() {
 	dev->height = 480;
 	dev->format = V4L2_PIX_FMT_YUYV;
 	dev->standard = V4L2_STD_UNKNOWN;
-	dev->n_buffers = max_u(sysconf(_SC_NPROCESSORS_ONLN), 1) + 1;
+	dev->n_buffers = max_u(min_u(sysconf(_SC_NPROCESSORS_ONLN), 4), 1) + 1;
 	dev->n_workers = dev->n_buffers;
 	dev->timeout = 1;
 	dev->error_delay = 1;
@@ -177,8 +177,8 @@ void device_close(struct device_t *dev) {
 		for (unsigned index = 0; index < dev->run->n_buffers; ++index) {
 #			define HW_BUFFER(_next) dev->run->hw_buffers[index]._next
 
-			if (HW_BUFFER(size) > 0 && HW_BUFFER(data) != MAP_FAILED) {
-				if (munmap(HW_BUFFER(data), HW_BUFFER(size)) < 0) {
+			if (HW_BUFFER(allocated) > 0 && HW_BUFFER(data) != MAP_FAILED) {
+				if (munmap(HW_BUFFER(data), HW_BUFFER(allocated)) < 0) {
 					LOG_PERROR("Can't unmap device buffer %u", index);
 				}
 			}
@@ -201,6 +201,77 @@ void device_close(struct device_t *dev) {
 	}
 }
 
+int device_switch_capturing(struct device_t *dev, bool enable) {
+	if (enable != dev->run->capturing) {
+		enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+
+		LOG_DEBUG("Calling ioctl(%s) ...", (enable ? "VIDIOC_STREAMON" : "VIDIOC_STREAMOFF"));
+		if (xioctl(dev->run->fd, (enable ? VIDIOC_STREAMON : VIDIOC_STREAMOFF), &type) < 0) {
+			LOG_PERROR("Unable to %s capturing", (enable ? "start" : "stop"));
+			if (enable) {
+				return -1;
+			}
+		}
+
+		dev->run->capturing = enable;
+		LOG_INFO("Capturing %s", (enable ? "started" : "stopped"));
+	}
+    return 0;
+}
+
+int device_grab_buffer(struct device_t *dev) {
+	struct v4l2_buffer buf_info;
+
+	MEMSET_ZERO(buf_info);
+	buf_info.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	buf_info.memory = V4L2_MEMORY_MMAP;
+
+	LOG_DEBUG("Calling ioctl(VIDIOC_DQBUF) ...");
+	if (xioctl(dev->run->fd, VIDIOC_DQBUF, &buf_info) < 0) {
+		LOG_PERROR("Unable to dequeue buffer");
+		return -1;
+	}
+
+	LOG_DEBUG("Got a new frame in buffer index=%u; bytesused=%u", buf_info.index, buf_info.bytesused);
+	if (buf_info.index >= dev->run->n_buffers) {
+		LOG_ERROR("Got invalid buffer index=%u; nbuffers=%u", buf_info.index, dev->run->n_buffers);
+		return -1;
+	}
+
+	dev->run->hw_buffers[buf_info.index].used = buf_info.bytesused;
+	memcpy(&dev->run->hw_buffers[buf_info.index].buf_info, &buf_info, sizeof(struct v4l2_buffer));
+	return buf_info.index;
+}
+
+int device_release_buffer(struct device_t *dev, unsigned index) {
+	LOG_DEBUG("Calling ioctl(VIDIOC_QBUF) ...");
+	if (xioctl(dev->run->fd, VIDIOC_QBUF, &dev->run->hw_buffers[index].buf_info) < 0) {
+		LOG_PERROR("Unable to requeue buffer");
+		return -1;
+	}
+	dev->run->hw_buffers[index].used = 0;
+	return 0;
+}
+
+int device_consume_event(struct device_t *dev) {
+	struct v4l2_event event;
+
+	LOG_DEBUG("Calling ioctl(VIDIOC_DQEVENT) ...");
+	if (!xioctl(dev->run->fd, VIDIOC_DQEVENT, &event)) {
+		switch (event.type) {
+			case V4L2_EVENT_SOURCE_CHANGE:
+				LOG_INFO("Got V4L2_EVENT_SOURCE_CHANGE: source changed");
+				return -1;
+			case V4L2_EVENT_EOS:
+				LOG_INFO("Got V4L2_EVENT_EOS: end of stream (ignored)");
+				return 0;
+		}
+	} else {
+		LOG_PERROR("Got some V4L2 device event, but where is it? ");
+	}
+	return 0;
+}
+
 static int _device_open_check_cap(struct device_t *dev) {
 	struct v4l2_capability cap;
 	int input = dev->input; // Needs pointer to int for ioctl()
@@ -397,7 +468,7 @@ static int _device_open_mmap(struct device_t *dev) {
 			LOG_PERROR("Can't map device buffer %u", dev->run->n_buffers);
 			return -1;
 		}
-		HW_BUFFER(size) = buf_info.length;
+		HW_BUFFER(allocated) = buf_info.length;
 
 #		undef HW_BUFFER
 	}

src/device.h

@@ -42,13 +42,15 @@
 
 
 struct hw_buffer_t {
-	unsigned char	*data;
-	size_t			size;
+	unsigned char		*data;
+	size_t				used;
+	size_t				allocated;
+	struct v4l2_buffer	buf_info;
 };
 
 struct picture_t {
 	unsigned char	*data;
-	size_t			size;
+	size_t			used;
 	size_t			allocated;
 	long double		grab_time;
 	long double		encode_begin_time;
@@ -116,3 +118,8 @@ v4l2_std_id device_parse_standard(const char *str);
 
 int device_open(struct device_t *dev);
 void device_close(struct device_t *dev);
+
+int device_switch_capturing(struct device_t *dev, bool enable);
+int device_grab_buffer(struct device_t *dev);
+int device_release_buffer(struct device_t *dev, unsigned index);
+int device_consume_event(struct device_t *dev);

src/encoders/cpu/encoder.c

@@ -81,8 +81,8 @@ void cpu_encoder_compress_buffer(struct device_t *dev, unsigned index, unsigned
 
 #	define PICTURE(_next) dev->run->pictures[index]._next
 
-	PICTURE(size) = 0;
-	_jpeg_set_dest_picture(&jpeg, PICTURE(data), &PICTURE(size));
+	PICTURE(used) = 0;
+	_jpeg_set_dest_picture(&jpeg, PICTURE(data), &PICTURE(used));
 
 	jpeg.image_width = dev->run->width;
 	jpeg.image_height = dev->run->height;
@@ -112,8 +112,8 @@ void cpu_encoder_compress_buffer(struct device_t *dev, unsigned index, unsigned
 	// https://stackoverflow.com/questions/19857766/error-handling-in-libjpeg
 	jpeg_finish_compress(&jpeg);
 	jpeg_destroy_compress(&jpeg);
-	assert(PICTURE(size) > 0);
-	assert(PICTURE(size) <= dev->run->max_picture_size);
+	assert(PICTURE(used) > 0);
+	assert(PICTURE(used) <= dev->run->max_picture_size);
 }
 
 static void _jpeg_set_dest_picture(j_compress_ptr jpeg, unsigned char *picture, size_t *written) {

src/encoders/hw/encoder.c

@@ -69,8 +69,8 @@ void hw_encoder_compress_buffer(struct device_t *dev, unsigned index) {
 #	define PICTURE(_next)	dev->run->pictures[index]._next
 #	define HW_BUFFER(_next)	dev->run->hw_buffers[index]._next
 
-	assert(PICTURE(allocated) >= HW_BUFFER(size) + sizeof(HUFFMAN_TABLE));
-	PICTURE(size) = _memcpy_with_huffman(PICTURE(data), HW_BUFFER(data), HW_BUFFER(size));
+	assert(PICTURE(allocated) >= HW_BUFFER(used) + sizeof(HUFFMAN_TABLE));
+	PICTURE(used) = _memcpy_with_huffman(PICTURE(data), HW_BUFFER(data), HW_BUFFER(used));
 
 #	undef HW_BUFFER
 #	undef PICTURE

src/encoders/omx/encoder.c

@@ -42,8 +42,8 @@
 #include "encoder.h"
 
 
-#define INPUT_PORT 340
-#define OUTPUT_PORT 341
+static const OMX_U32 _INPUT_PORT = 340;
+static const OMX_U32 _OUTPUT_PORT = 341;
 
 
 static int _i_omx = 0;
@@ -178,7 +178,7 @@ int omx_encoder_compress_buffer(struct omx_encoder_t *omx, struct device_t *dev,
 #	define OUT(_next)		omx->output_buffer->_next
 
 	OMX_ERRORTYPE error;
-	size_t slice_size = IN(nAllocLen);
+	size_t slice_size = (IN(nAllocLen) < HW_BUFFER(used) ? IN(nAllocLen) : HW_BUFFER(used));
 	size_t pos = 0;
 
 	if ((error = OMX_FillThisBuffer(omx->encoder, omx->output_buffer)) != OMX_ErrorNone) {
@@ -186,7 +186,7 @@ int omx_encoder_compress_buffer(struct omx_encoder_t *omx, struct device_t *dev,
 		return -1;
 	}
 
-	PICTURE(size) = 0;
+	PICTURE(used) = 0;
 	omx->output_available = false;
 	omx->input_required = true;
 
@@ -198,9 +198,9 @@ int omx_encoder_compress_buffer(struct omx_encoder_t *omx, struct device_t *dev,
 		if (omx->output_available) {
 			omx->output_available = false;
 
-			assert(PICTURE(size) + OUT(nFilledLen) <= dev->run->max_picture_size);
-			memcpy(PICTURE(data) + PICTURE(size), OUT(pBuffer) + OUT(nOffset), OUT(nFilledLen));
-			PICTURE(size) += OUT(nFilledLen);
+			assert(PICTURE(used) + OUT(nFilledLen) <= dev->run->max_picture_size);
+			memcpy(PICTURE(data) + PICTURE(used), OUT(pBuffer) + OUT(nOffset), OUT(nFilledLen));
+			PICTURE(used) += OUT(nFilledLen);
 
 			if (OUT(nFlags) & OMX_BUFFERFLAG_ENDOFFRAME) {
 				OUT(nFlags) = 0;
@@ -216,7 +216,7 @@ int omx_encoder_compress_buffer(struct omx_encoder_t *omx, struct device_t *dev,
 		if (omx->input_required) {
 			omx->input_required = false;
 
-			if (pos == HW_BUFFER(size)) {
+			if (pos == HW_BUFFER(used)) {
 				continue;
 			}
 
@@ -226,8 +226,8 @@ int omx_encoder_compress_buffer(struct omx_encoder_t *omx, struct device_t *dev,
 
 			pos += slice_size;
 
-			if (pos + slice_size > HW_BUFFER(size)) {
-				slice_size = HW_BUFFER(size) - pos;
+			if (pos + slice_size > HW_BUFFER(used)) {
+				slice_size = HW_BUFFER(used) - pos;
 			}
 
 			if ((error = OMX_EmptyThisBuffer(omx->encoder, omx->input_buffer)) != OMX_ErrorNone) {
@@ -300,7 +300,7 @@ static int _omx_setup_input(struct omx_encoder_t *omx, struct device_t *dev) {
 
 	LOG_DEBUG("Setting up OMX JPEG input port ...");
 
-	if (component_get_portdef(&omx->encoder, &portdef, INPUT_PORT) < 0) {
+	if (component_get_portdef(&omx->encoder, &portdef, _INPUT_PORT) < 0) {
 		LOG_ERROR("... first");
 		return -1;
 	}
@@ -338,17 +338,17 @@ static int _omx_setup_input(struct omx_encoder_t *omx, struct device_t *dev) {
 		return -1;
 	}
 
-	if (component_get_portdef(&omx->encoder, &portdef, INPUT_PORT) < 0) {
+	if (component_get_portdef(&omx->encoder, &portdef, _INPUT_PORT) < 0) {
 		LOG_ERROR("... second");
 		return -1;
 	}
 
-	if (component_enable_port(&omx->encoder, INPUT_PORT) < 0) {
+	if (component_enable_port(&omx->encoder, _INPUT_PORT) < 0) {
 		return -1;
 	}
 	omx->i_input_port_enabled = true;
 
-	if ((error = OMX_AllocateBuffer(omx->encoder, &omx->input_buffer, INPUT_PORT, NULL, portdef.nBufferSize)) != OMX_ErrorNone) {
+	if ((error = OMX_AllocateBuffer(omx->encoder, &omx->input_buffer, _INPUT_PORT, NULL, portdef.nBufferSize)) != OMX_ErrorNone) {
 		LOG_OMX_ERROR(error, "Can't allocate OMX JPEG input buffer");
 		return -1;
 	}
@@ -361,7 +361,7 @@ static int _omx_setup_output(struct omx_encoder_t *omx, unsigned quality) {
 
 	LOG_DEBUG("Setting up OMX JPEG output port ...");
 
-	if (component_get_portdef(&omx->encoder, &portdef, OUTPUT_PORT) < 0) {
+	if (component_get_portdef(&omx->encoder, &portdef, _OUTPUT_PORT) < 0) {
 		LOG_ERROR("... first");
 		return -1;
 	}
@@ -374,7 +374,7 @@ static int _omx_setup_output(struct omx_encoder_t *omx, unsigned quality) {
 		return -1;
 	}
 
-	if (component_get_portdef(&omx->encoder, &portdef, OUTPUT_PORT) < 0) {
+	if (component_get_portdef(&omx->encoder, &portdef, _OUTPUT_PORT) < 0) {
 		LOG_ERROR("... second");
 		return -1;
 	}
@@ -395,7 +395,7 @@ static int _omx_setup_output(struct omx_encoder_t *omx, unsigned quality) {
 		OMX_PARAM_IJGSCALINGTYPE ijg;
 
 		OMX_INIT_STRUCTURE(ijg);
-		ijg.nPortIndex = OUTPUT_PORT;
+		ijg.nPortIndex = _OUTPUT_PORT;
 		ijg.bEnabled = OMX_TRUE;
 
 		if ((error = OMX_SetParameter(omx->encoder, OMX_IndexParamBrcmEnableIJGTableScaling, &ijg)) != OMX_ErrorNone) {
@@ -408,7 +408,7 @@ static int _omx_setup_output(struct omx_encoder_t *omx, unsigned quality) {
 		OMX_IMAGE_PARAM_QFACTORTYPE qfactor;
 
 		OMX_INIT_STRUCTURE(qfactor);
-		qfactor.nPortIndex = OUTPUT_PORT;
+		qfactor.nPortIndex = _OUTPUT_PORT;
 		qfactor.nQFactor = quality;
 
 		if ((error = OMX_SetParameter(omx->encoder, OMX_IndexParamQFactor, &qfactor)) != OMX_ErrorNone) {
@@ -417,12 +417,12 @@ static int _omx_setup_output(struct omx_encoder_t *omx, unsigned quality) {
 		}
 	}
 
-	if (component_enable_port(&omx->encoder, OUTPUT_PORT) < 0) {
+	if (component_enable_port(&omx->encoder, _OUTPUT_PORT) < 0) {
 		return -1;
 	}
 	omx->i_output_port_enabled = true;
 
-	if ((error = OMX_AllocateBuffer(omx->encoder, &omx->output_buffer, OUTPUT_PORT, NULL, portdef.nBufferSize)) != OMX_ErrorNone) {
+	if ((error = OMX_AllocateBuffer(omx->encoder, &omx->output_buffer, _OUTPUT_PORT, NULL, portdef.nBufferSize)) != OMX_ErrorNone) {
 		LOG_OMX_ERROR(error, "Can't allocate OMX JPEG output buffer");
 		return -1;
 	}
@@ -434,23 +434,23 @@ static int _omx_encoder_clear_ports(struct omx_encoder_t *omx) {
 	int retcode = 0;
 
 	if (omx->i_output_port_enabled) {
-		retcode -= component_disable_port(&omx->encoder, OUTPUT_PORT);
+		retcode -= component_disable_port(&omx->encoder, _OUTPUT_PORT);
 		omx->i_output_port_enabled = false;
 	}
 	if (omx->i_input_port_enabled) {
-		retcode -= component_disable_port(&omx->encoder, INPUT_PORT);
+		retcode -= component_disable_port(&omx->encoder, _INPUT_PORT);
 		omx->i_input_port_enabled = false;
 	}
 
 	if (omx->input_buffer) {
-		if ((error = OMX_FreeBuffer(omx->encoder, INPUT_PORT, omx->input_buffer)) != OMX_ErrorNone) {
+		if ((error = OMX_FreeBuffer(omx->encoder, _INPUT_PORT, omx->input_buffer)) != OMX_ErrorNone) {
 			LOG_OMX_ERROR(error, "Can't free OMX JPEG input buffer");
 			// retcode -= 1;
 		}
 		omx->input_buffer = NULL;
 	}
 	if (omx->output_buffer) {
-		if ((error = OMX_FreeBuffer(omx->encoder, OUTPUT_PORT, omx->output_buffer)) != OMX_ErrorNone) {
+		if ((error = OMX_FreeBuffer(omx->encoder, _OUTPUT_PORT, omx->output_buffer)) != OMX_ErrorNone) {
 			LOG_OMX_ERROR(error, "Can't free OMX JPEG output buffer");
 			// retcode -= 1;
 		}

src/http.c

@@ -22,6 +22,7 @@
 
 #include <stdlib.h>
 #include <stdbool.h>
+#include <stdatomic.h>
 #include <string.h>
 #include <strings.h>
 #include <unistd.h>
@@ -323,18 +324,22 @@ static void _http_callback_snapshot(struct evhttp_request *request, void *v_serv
 #	define EXPOSED(_next) server->run->exposed->_next
 
 	assert((buf = evbuffer_new()));
-	assert(!evbuffer_add(buf, (const void *)EXPOSED(picture.data), EXPOSED(picture.size)));
+	assert(!evbuffer_add(buf, (const void *)EXPOSED(picture.data), EXPOSED(picture.used)));
 
 	ADD_HEADER("Access-Control-Allow-Origin:", "*");
 	ADD_HEADER("Cache-Control", "no-store, no-cache, must-revalidate, proxy-revalidate, pre-check=0, post-check=0, max-age=0");
 	ADD_HEADER("Pragma", "no-cache");
 	ADD_HEADER("Expires", "Mon, 3 Jan 2000 12:34:56 GMT");
 
-#	define ADD_TIME_HEADER(_key, _value) \
-		{ sprintf(header_buf, "%.06Lf", _value); ADD_HEADER(_key, header_buf); }
+#	define ADD_TIME_HEADER(_key, _value) { \
+			sprintf(header_buf, "%.06Lf", _value); \
+			ADD_HEADER(_key, header_buf); \
+		}
 
-#	define ADD_UNSIGNED_HEADER(_key, _value) \
-		{ sprintf(header_buf, "%u", _value); ADD_HEADER(_key, header_buf); }
+#	define ADD_UNSIGNED_HEADER(_key, _value) { \
+			sprintf(header_buf, "%u", _value); \
+			ADD_HEADER(_key, header_buf); \
+		}
 
 	ADD_TIME_HEADER("X-Timestamp", get_now_real());
 
@@ -415,13 +420,8 @@ static void _http_callback_stream(struct evhttp_request *request, void *v_server
 		}
 
 		evhttp_connection_get_peer(conn, &client_addr, &client_port);
-		LOG_INFO("HTTP: Registered the new stream client: [%s]:%u; id=%s; advance_headers=%s; dual_final_frames=%s; clients now: %u",
-			client_addr,
-			client_port,
-			client->id,
-			bool_to_string(client->advance_headers),
-			bool_to_string(client->dual_final_frames),
-			server->run->stream_clients_count);
+		LOG_INFO("HTTP: Registered the new stream client: [%s]:%u; id=%s; clients now: %u",
+			client_addr, client_port, client->id, server->run->stream_clients_count);
 
 		buf_event = evhttp_connection_get_bufferevent(conn);
 		bufferevent_setcb(buf_event, NULL, NULL, _http_callback_stream_error, (void *)client);
@@ -471,8 +471,8 @@ static void _http_callback_stream_write(struct bufferevent *buf_event, void *v_c
 	// по тем же причинам, по которым у нас нет Content-Length.
 
 #	define ADD_ADVANCE_HEADERS \
-		{ assert(evbuffer_add_printf(buf, \
-		"Content-Type: image/jpeg" RN "X-Timestamp: %.06Lf" RN RN, get_now_real())); }
+		assert(evbuffer_add_printf(buf, \
+			"Content-Type: image/jpeg" RN "X-Timestamp: %.06Lf" RN RN, get_now_real()))
 
 	if (client->need_initial) {
 		assert(evbuffer_add_printf(buf,
@@ -505,7 +505,7 @@ static void _http_callback_stream_write(struct bufferevent *buf_event, void *v_c
 			"Content-Length: %zu" RN
 			"X-Timestamp: %.06Lf" RN
 			"%s",
-			EXPOSED(picture.size) * sizeof(*EXPOSED(picture.data)),
+			EXPOSED(picture.used) * sizeof(*EXPOSED(picture.data)),
 			get_now_real(), (client->extra_headers ? "" : RN)
 		));
 		if (client->extra_headers) {
@@ -541,7 +541,7 @@ static void _http_callback_stream_write(struct bufferevent *buf_event, void *v_c
 
 	assert(!evbuffer_add(buf,
 		(void *)EXPOSED(picture.data),
-		EXPOSED(picture.size) * sizeof(*EXPOSED(picture.data))
+		EXPOSED(picture.used) * sizeof(*EXPOSED(picture.data))
 	));
 	assert(evbuffer_add_printf(buf, RN "--" BOUNDARY RN));
 
@@ -652,13 +652,15 @@ static void _http_exposed_refresh(UNUSED int fd, UNUSED short what, void *v_serv
 	bool stream_updated = false;
 	bool picture_updated = false;
 
-#	define UNLOCK_STREAM \
-		{ server->run->stream->updated = false; A_MUTEX_UNLOCK(&server->run->stream->mutex); }
+#	define UNLOCK_STREAM { \
+			atomic_store(&server->run->stream->updated, false); \
+			A_MUTEX_UNLOCK(&server->run->stream->mutex); \
+		}
 
-	if (server->run->stream->updated) {
+	if (atomic_load(&server->run->stream->updated)) {
 		LOG_DEBUG("Refreshing HTTP exposed ...");
 		A_MUTEX_LOCK(&server->run->stream->mutex);
-		if (server->run->stream->picture.size > 0) { // If online
+		if (server->run->stream->picture.used > 0) { // If online
 			picture_updated = _expose_new_picture(server);
 			UNLOCK_STREAM;
 		} else {
@@ -681,19 +683,19 @@ static bool _expose_new_picture(struct http_server_t *server) {
 #	define STREAM(_next) server->run->stream->_next
 #	define EXPOSED(_next) server->run->exposed->_next
 
-	assert(STREAM(picture.size) > 0);
+	assert(STREAM(picture.used) > 0);
 	EXPOSED(captured_fps) = STREAM(captured_fps);
 	EXPOSED(expose_begin_time) = get_now_monotonic();
 
 #	define MEM_STREAM_TO_EXPOSED \
 		EXPOSED(picture.data), STREAM(picture.data), \
-		STREAM(picture.size) * sizeof(*STREAM(picture.data))
+		STREAM(picture.used) * sizeof(*STREAM(picture.data))
 
 	if (server->drop_same_frames) {
 		if (
 			EXPOSED(online)
 			&& EXPOSED(dropped) < server->drop_same_frames
-			&& EXPOSED(picture.size) == STREAM(picture.size)
+			&& EXPOSED(picture.used) == STREAM(picture.used)
 			&& !memcmp(MEM_STREAM_TO_EXPOSED)
 		) {
 			EXPOSED(expose_cmp_time) = get_now_monotonic();
@@ -718,7 +720,7 @@ static bool _expose_new_picture(struct http_server_t *server) {
 
 #	undef MEM_STREAM_TO_EXPOSED
 
-	EXPOSED(picture.size) = STREAM(picture.size);
+	EXPOSED(picture.used) = STREAM(picture.used);
 
 	EXPOSED(picture.grab_time) = STREAM(picture.grab_time);
 	EXPOSED(picture.encode_begin_time) = STREAM(picture.encode_begin_time);
@@ -746,7 +748,7 @@ static bool _expose_blank_picture(struct http_server_t *server) {
 	EXPOSED(expose_begin_time) = get_now_monotonic();
 	EXPOSED(expose_cmp_time) = EXPOSED(expose_begin_time);
 
-	if (EXPOSED(online) || EXPOSED(picture.size) == 0) {
+	if (EXPOSED(online) || EXPOSED(picture.used) == 0) {
 		if (EXPOSED(picture.allocated) < BLANK_JPEG_LEN) {
 			A_REALLOC(EXPOSED(picture.data), BLANK_JPEG_LEN);
 			EXPOSED(picture.allocated) = BLANK_JPEG_LEN;
@@ -754,7 +756,7 @@ static bool _expose_blank_picture(struct http_server_t *server) {
 
 		memcpy(EXPOSED(picture.data), BLANK_JPEG_DATA, BLANK_JPEG_LEN * sizeof(*EXPOSED(picture.data)));
 
-		EXPOSED(picture.size) = BLANK_JPEG_LEN;
+		EXPOSED(picture.used) = BLANK_JPEG_LEN;
 
 		EXPOSED(picture.grab_time) = 0;
 		EXPOSED(picture.encode_begin_time) = 0;

src/main.c

@@ -41,8 +41,8 @@
 #include "http.h"
 
 
-static const char _short_opts[] = "d:i:x:y:m:a:f:z:tb:w:q:c:s:p:u:ro:e:h";
-static const struct option _long_opts[] = {
+static const char _SHORT_OPTS[] = "d:i:x:y:m:a:f:z:ntb:w:q:c:s:p:u:ro:e:lhv";
+static const struct option _LONG_OPTS[] = {
 	{"device",					required_argument,	NULL,	'd'},
 	{"input",					required_argument,	NULL,	'i'},
 	{"width",					required_argument,	NULL,	'x'},
@@ -51,14 +51,14 @@ static const struct option _long_opts[] = {
 	{"tv-standard",				required_argument,	NULL,	'a'},
 	{"desired-fps",				required_argument,	NULL,	'f'},
 	{"min-frame-size",			required_argument,	NULL,	'z'},
+	{"persistent",				no_argument,		NULL,	'n'},
 	{"dv-timings",				no_argument,		NULL,	't'},
 	{"buffers",					required_argument,	NULL,	'b'},
 	{"workers",					required_argument,	NULL,	'w'},
 	{"quality",					required_argument,	NULL,	'q'},
 	{"encoder",					required_argument,	NULL,	'c'},
 	{"device-timeout",			required_argument,	NULL,	1000},
-	{"device-persistent",		no_argument,		NULL,	1001},
-	{"device-error-delay",		required_argument,	NULL,	1002},
+	{"device-error-delay",		required_argument,	NULL,	1001},
 
 	{"brightness",				required_argument,	NULL,	2000},
 	{"brightness-auto",			no_argument,		NULL,	2001},
@@ -80,7 +80,7 @@ static const struct option _long_opts[] = {
 	{"unix-rm",					no_argument,		NULL,	'r'},
 	{"unix-mode",				required_argument,	NULL,	'o'},
 	{"drop-same-frames",		required_argument,	NULL,	'e'},
-	{"slowdown",				no_argument,		NULL,	3000},
+	{"slowdown",				no_argument,		NULL,	'l'},
 	{"fake-width",				required_argument,	NULL,	3001},
 	{"fake-height",				required_argument,	NULL,	3002},
 	{"server-timeout",			required_argument,	NULL,	3003},
@@ -90,7 +90,7 @@ static const struct option _long_opts[] = {
 	{"debug",					no_argument,		NULL,	5002},
 	{"log-level",				required_argument,	NULL,	5010},
 	{"help",					no_argument,		NULL,	'h'},
-	{"version",					no_argument,		NULL,	6000},
+	{"version",					no_argument,		NULL,	'v'},
 	{NULL, 0, NULL, 0},
 };
 
@@ -106,78 +106,79 @@ static void _version(bool nl) {
 
 static void _help(struct device_t *dev, struct encoder_t *encoder, struct http_server_t *server) {
 	printf("\nuStreamer - Lightweight and fast MJPG-HTTP streamer\n");
-	printf("===================================================\n\n");
+	printf("═══════════════════════════════════════════════════\n\n");
 	printf("Version: ");
 	_version(false);
 	printf("; license: GPLv3\n");
 	printf("Copyright (C) 2018 Maxim Devaev <mdevaev@gmail.com>\n\n");
 	printf("Capturing options:\n");
-	printf("------------------\n");
-	printf("    -d|--device </dev/path>          -- Path to V4L2 device. Default: %s.\n\n", dev->path);
-	printf("    -i|--input <N>                   -- Input channel. Default: %u.\n\n", dev->input);
-	printf("    -x|--width <N>                   -- Initial image width. Default: %u.\n\n", dev->width);
-	printf("    -y|--height <N>                  -- Initial image height. Default: %u.\n\n", dev->height);
-	printf("    -m|--format <fmt>                -- Image format.\n");
-	printf("                                        Available: %s; default: YUYV.\n\n", FORMATS_STR);
-	printf("    -a|--tv-standard <std>           -- Force TV standard.\n");
-	printf("                                        Available: %s; default: disabled.\n\n", STANDARDS_STR);
-	printf("    -f|--desired-fps <N>             -- Desired FPS. Default: maximum as possible.\n\n");
-	printf("    -z|--min-frame-size <N>          -- Drop frames smaller then this limit.\n");
-	printf("                                        Useful if the device produces small-sized garbage frames.\n\n");
-	printf("    -t|--dv-timings                  -- Enable DV timings queriyng and events processing.\n");
-	printf("                                        Supports automatic resolution changing. Default: disabled.\n\n");
-	printf("    -b|--buffers <N>                 -- The number of buffers to receive data from the device.\n");
-	printf("                                        Each buffer may processed using an intermediate thread.\n");
-	printf("                                        Default: %u (number of CPU cores + 1)\n\n", dev->n_buffers);
-	printf("    -w|--workers <N>                 -- The number of compressing threads. Default: %u (== --buffers).\n\n", dev->n_workers);
-	printf("    -q|--quality <N>                 -- Set quality of JPEG encoding from 1 to 100 (best). Default: %u.\n\n", encoder->quality);
-	printf("    -c|--encoder <type>              -- Use specified encoder. It may affects to workers number.\n");
-	printf("                                     -- Available: %s; default: CPU.\n\n", ENCODER_TYPES_STR);
-	printf("    --device-timeout <seconds>       -- Timeout for device querying. Default: %u\n\n", dev->timeout);
-	printf("    --device-persistent              -- Don't re-initialize device on timeout. Default: disabled.\n\n");
-	printf("    --device-error-delay <seconds>   -- Delay before trying to connect to the device again\n");
-	printf("                                        after a timeout. Default: %u\n\n", dev->error_delay);
+	printf("══════════════════\n");
+	printf("    -d|--device </dev/path>  ──────── Path to V4L2 device. Default: %s.\n\n", dev->path);
+	printf("    -i|--input <N>  ───────────────── Input channel. Default: %u.\n\n", dev->input);
+	printf("    -x|--width <N>  ───────────────── Initial image width. Default: %u.\n\n", dev->width);
+	printf("    -y|--height <N>  ──────────────── Initial image height. Default: %u.\n\n", dev->height);
+	printf("    -m|--format <fmt>  ────────────── Image format.\n");
+	printf("                                      Available: %s; default: YUYV.\n\n", FORMATS_STR);
+	printf("    -a|--tv-standard <std>  ───────── Force TV standard.\n");
+	printf("                                      Available: %s; default: disabled.\n\n", STANDARDS_STR);
+	printf("    -f|--desired-fps <N>  ─────────── Desired FPS. Default: maximum as possible.\n\n");
+	printf("    -z|--min-frame-size <N>  ──────── Drop frames smaller then this limit.\n");
+	printf("                                      Useful if the device produces small-sized garbage frames.\n\n");
+	printf("    -n|--persistent  ──────────────── Don't re-initialize device on timeout. Default: disabled.\n\n");
+	printf("    -t|--dv-timings  ──────────────── Enable DV timings queriyng and events processing.\n");
+	printf("                                      Supports automatic resolution changing. Default: disabled.\n\n");
+	printf("    -b|--buffers <N>  ─────────────── The number of buffers to receive data from the device.\n");
+	printf("                                      Each buffer may processed using an intermediate thread.\n");
+	printf("                                      Default: %u (the number of CPU cores (but not more 4) + 1)\n\n", dev->n_buffers);
+	printf("    -w|--workers <N>  ─────────────── The number of worker threads. Default: %u (== --buffers).\n\n", dev->n_workers);
+	printf("    -q|--quality <N>  ─────────────── Set quality of JPEG encoding from 1 to 100 (best). Default: %u.\n\n", encoder->quality);
+	printf("    -c|--encoder <type>  ──────────── Use specified encoder. It may affects to workers number.\n");
+	printf("                                      Available: %s; default: CPU.\n\n", ENCODER_TYPES_STR);
+	printf("    --device-timeout <seconds>  ───── Timeout for device querying. Default: %u\n\n", dev->timeout);
+	printf("    --device-error-delay <seconds>  ─ Delay before trying to connect to the device again\n");
+	printf("                                      after timeout. Default: %u\n\n", dev->error_delay);
 	printf("Image control options:\n");
-	printf("---------------\n");
-	printf("    --brightness <N>             -- Set brightness. Default: no change.\n\n");
-	printf("    --brightness-auto            -- Enable automatic brightness control. Default: no change.\n\n");
-	printf("    --contrast <N>               -- Set contrast. Default: no change.\n\n");
-	printf("    --saturation <N>             -- Set saturation. Default: no change.\n\n");
-	printf("    --hue <N>                    -- Set hue. Default: no change.\n\n");
-	printf("    --hue-auto                   -- Enable automatic hue control. Default: no change.\n\n");
-	printf("    --gamma <N>                  -- Set gamma. Default: no change.\n\n");
-	printf("    --sharpness <N>              -- Set sharpness. Default: no change.\n\n");
-	printf("    --backlight-compensation <N> -- Set backlight compensation. Default: no change.\n\n");
-	printf("    --white-balance <N>          -- Set white balance. Default: no change.\n\n");
-	printf("    --white-balance-auto         -- Enable automatic white balance control. Default: no change.\n\n");
-	printf("    --gain <N>                   -- Set gain. Default: no change.\n\n");
-	printf("    --gain-auto                  -- Enable automatic gain control. Default: no change.\n\n");
+	printf("══════════════════════\n");
+	printf("    --brightness <N>  ───────────── Set brightness. Default: no change.\n\n");
+	printf("    --brightness-auto  ──────────── Enable automatic brightness control. Default: no change.\n\n");
+	printf("    --contrast <N>  ─────────────── Set contrast. Default: no change.\n\n");
+	printf("    --saturation <N>  ───────────── Set saturation. Default: no change.\n\n");
+	printf("    --hue <N>  ──────────────────── Set hue. Default: no change.\n\n");
+	printf("    --hue-auto  ─────────────────── Enable automatic hue control. Default: no change.\n\n");
+	printf("    --gamma <N>  ────────────────── Set gamma. Default: no change.\n\n");
+	printf("    --sharpness <N>  ────────────── Set sharpness. Default: no change.\n\n");
+	printf("    --backlight-compensation <N>  ─ Set backlight compensation. Default: no change.\n\n");
+	printf("    --white-balance <N>  ────────── Set white balance. Default: no change.\n\n");
+	printf("    --white-balance-auto  ───────── Enable automatic white balance control. Default: no change.\n\n");
+	printf("    --gain <N>  ─────────────────── Set gain. Default: no change.\n\n");
+	printf("    --gain-auto  ────────────────── Enable automatic gain control. Default: no change.\n\n");
 	printf("HTTP server options:\n");
-	printf("--------------------\n");
-	printf("    -s|--host <address>        -- Listen on Hostname or IP. Default: %s\n\n", server->host);
-	printf("    -p|--port <N>              -- Bind to this TCP port. Default: %u\n\n", server->port);
-	printf("    -u|--unix <path>           -- Bind to UNIX domain socket. Default: disabled\n\n");
-	printf("    -r|--unix-rm               -- Try to remove old UNIX socket file before binding. Default: disabled\n\n");
-	printf("    -o|--unix-mode <mode>      -- Set UNIX socket file permissions (like 777). Default: disabled\n\n");
-	printf("    -e|--drop-same-frames <N>  -- Don't send same frames to clients, but no more than specified number.\n");
+	printf("════════════════════\n");
+	printf("    -s|--host <address>  ──────── Listen on Hostname or IP. Default: %s\n\n", server->host);
+	printf("    -p|--port <N>  ────────────── Bind to this TCP port. Default: %u\n\n", server->port);
+	printf("    -u|--unix <path>  ─────────── Bind to UNIX domain socket. Default: disabled\n\n");
+	printf("    -r|--unix-rm  ─────────────── Try to remove old UNIX socket file before binding. Default: disabled\n\n");
+	printf("    -o|--unix-mode <mode>  ────── Set UNIX socket file permissions (like 777). Default: disabled\n\n");
+	printf("    -e|--drop-same-frames <N>  ── Don't send same frames to clients, but no more than specified number.\n");
 	printf("                                  It can significantly reduce the outgoing traffic, but will increase\n");
 	printf("                                  the CPU loading. Don't use this option with analog signal sources\n");
 	printf("                                  or webcams, it's useless. Default: disabled.\n\n");
-	printf("    --slowdown                 -- Slowdown capturing to 1 FPS or less when no stream clients connected.\n");
+	printf("    -l|--slowdown  ────────────── Slowdown capturing to 1 FPS or less when no stream clients connected.\n");
 	printf("                                  Useful to reduce CPU cosumption. Default: disabled.\n\n");
-	printf("    --fake-width <N>           -- Override image width for /state. Default: disabled\n\n");
-	printf("    --fake-height <N>          -- Override image height for /state. Default: disabled.\n\n");
-	printf("    --server-timeout <seconds> -- Timeout for client connections. Default: %u\n\n", server->timeout);
+	printf("    --fake-width <N>  ─────────── Override image width for /state. Default: disabled\n\n");
+	printf("    --fake-height <N>  ────────── Override image height for /state. Default: disabled.\n\n");
+	printf("    --server-timeout <seconds>  ─ Timeout for client connections. Default: %u\n\n", server->timeout);
 	printf("Misc options:\n");
-	printf("-------------\n");
-	printf("    --log-level <N> -- Verbosity level of messages from 0 (info) to 3 (debug).\n");
+	printf("═════════════\n");
+	printf("    --log-level <N>  ─ Verbosity level of messages from 0 (info) to 3 (debug).\n");
 	printf("                       Enabling debugging messages can slow down the program.\n");
 	printf("                       Available levels: 0=info, 1=performance, 2=verbose, 3=debug.\n");
 	printf("                       Default: %u.\n\n", log_level);
-	printf("    --perf          -- Enable performance messages (same as --log-level=1). Default: disabled.\n\n");
-	printf("    --verbose       -- Enable verbose messages and lower (same as --log-level=2). Default: disabled.\n\n");
-	printf("    --debug         -- Enable debug messages and lower (same as --log-level=3). Default: disabled.\n\n");
-	printf("    -h|--help       -- Print this messages and exit.\n\n");
+	printf("    --perf  ────────── Enable performance messages (same as --log-level=1). Default: disabled.\n\n");
+	printf("    --verbose  ─────── Enable verbose messages and lower (same as --log-level=2). Default: disabled.\n\n");
+	printf("    --debug  ───────── Enable debug messages and lower (same as --log-level=3). Default: disabled.\n\n");
+	printf("    -h|--help  ─────── Print this text and exit.\n\n");
+	printf("    -v|--version  ──── Print version and exit.\n\n");
 }
 
 static int _parse_options(int argc, char *argv[], struct device_t *dev, struct encoder_t *encoder, struct http_server_t *server) {
@@ -232,7 +233,7 @@ static int _parse_options(int argc, char *argv[], struct device_t *dev, struct e
 	int ch;
 
 	log_level = LOG_LEVEL_INFO;
-	while ((ch = getopt_long(argc, argv, _short_opts, _long_opts, &index)) >= 0) {
+	while ((ch = getopt_long(argc, argv, _SHORT_OPTS, _LONG_OPTS, &index)) >= 0) {
 		switch (ch) {
 			case 'd':	OPT_SET(dev->path, optarg);
 			case 'i':	OPT_UNSIGNED(dev->input, "--input", 0, 128);
@@ -245,14 +246,14 @@ static int _parse_options(int argc, char *argv[], struct device_t *dev, struct e
 			case 'a':	OPT_PARSE(dev->standard, device_parse_standard, STANDARD_UNKNOWN, "TV standard");
 			case 'f':	OPT_UNSIGNED(dev->desired_fps, "--desired-fps", 0, 30);
 			case 'z':	OPT_UNSIGNED(dev->min_frame_size, "--min-frame-size", 0, 8192);
+			case 'n':	OPT_SET(dev->persistent, true);
 			case 't':	OPT_SET(dev->dv_timings, true);
 			case 'b':	OPT_UNSIGNED(dev->n_buffers, "--buffers", 1, 32);
 			case 'w':	OPT_UNSIGNED(dev->n_workers, "--workers", 1, 32);
 			case 'q':	OPT_UNSIGNED(encoder->quality, "--quality", 1, 100);
 			case 'c':	OPT_PARSE(encoder->type, encoder_parse_type, ENCODER_TYPE_UNKNOWN, "encoder type");
 			case 1000:	OPT_UNSIGNED(dev->timeout, "--device-timeout", 1, 60);
-			case 1001:	OPT_SET(dev->persistent, true);
-			case 1002:	OPT_UNSIGNED(dev->error_delay, "--device-error-delay", 1, 60);
+			case 1001:	OPT_UNSIGNED(dev->error_delay, "--device-error-delay", 1, 60);
 
 			case 2000:	OPT_CTL(brightness);
 			case 2001:	OPT_CTL_AUTO(brightness);
@@ -284,7 +285,7 @@ static int _parse_options(int argc, char *argv[], struct device_t *dev, struct e
 			case 5002:	OPT_SET(log_level, LOG_LEVEL_DEBUG);
 			case 5010:	OPT_UNSIGNED(log_level, "--log-level", 0, 3);
 			case 'h':	_help(dev, encoder, server); return 1;
-			case 6000:	_version(true); return 1;
+			case 'v':	_version(true); return 1;
 			case 0:		break;
 			default:	_help(dev, encoder, server); return -1;
 		}

src/stream.c

@@ -20,6 +20,7 @@
 *****************************************************************************/
 
 
+#include <stdatomic.h>
 #include <unistd.h>
 #include <errno.h>
 #include <time.h>
@@ -48,21 +49,19 @@ static void _stream_init_workers(struct stream_t *stream, struct workers_pool_t
 static void *_stream_worker_thread(void *v_worker);
 static void _stream_destroy_workers(struct stream_t *stream, struct workers_pool_t *pool);
 
-static int _stream_control(struct device_t *dev, bool enable);
-static int _stream_grab_buffer(struct device_t *dev, struct v4l2_buffer *buf_info);
-static int _stream_release_buffer(struct device_t *dev, struct v4l2_buffer *buf_info);
-static int _stream_handle_event(struct device_t *dev);
-
 
 struct stream_t *stream_init(struct device_t *dev, struct encoder_t *encoder) {
 	struct process_t *proc;
 	struct stream_t *stream;
 
 	A_CALLOC(proc, 1);
+	atomic_init(&proc->stop, false);
+	atomic_init(&proc->slowdown, false);
 
 	A_CALLOC(stream, 1);
 	stream->dev = dev;
 	stream->encoder = encoder;
+	atomic_init(&stream->updated, false);
 	A_MUTEX_INIT(&stream->mutex);
 	stream->proc = proc;
 	return stream;
@@ -76,11 +75,10 @@ void stream_destroy(struct stream_t *stream) {
 
 void stream_loop(struct stream_t *stream) {
 	struct workers_pool_t pool;
-	bool workers_stop;
 
 	MEMSET_ZERO(pool);
+	atomic_init(&pool.workers_stop, false);
 	pool.encoder = stream->encoder;
-	pool.workers_stop = &workers_stop;
 
 	LOG_INFO("Using V4L2 device: %s", stream->dev->path);
 	LOG_INFO("Using desired FPS: %u", stream->dev->desired_fps);
@@ -99,7 +97,7 @@ void stream_loop(struct stream_t *stream) {
 
 		LOG_INFO("Capturing ...");
 
-		while (!stream->proc->stop) {
+		while (!atomic_load(&stream->proc->stop)) {
 			int free_worker_number = -1;
 
 			SEP_DEBUG('-');
@@ -109,7 +107,7 @@ void stream_loop(struct stream_t *stream) {
 			A_COND_WAIT_TRUE(pool.free_workers, &pool.free_workers_cond, &pool.free_workers_mutex);
 			A_MUTEX_UNLOCK(&pool.free_workers_mutex);
 
-			if (oldest_worker && !oldest_worker->has_job && oldest_worker->buf_index >= 0) {
+			if (oldest_worker && !atomic_load(&oldest_worker->has_job) && oldest_worker->buf_index >= 0) {
 				if (oldest_worker->job_failed) {
 					break;
 				}
@@ -123,7 +121,7 @@ void stream_loop(struct stream_t *stream) {
 			} else {
 				for (unsigned number = 0; number < stream->dev->n_workers; ++number) {
 					if (
-						!pool.workers[number].has_job && (
+						!atomic_load(&pool.workers[number].has_job) && (
 							free_worker_number == -1
 							|| pool.workers[free_worker_number].job_start_time < pool.workers[number].job_start_time
 						)
@@ -134,16 +132,16 @@ void stream_loop(struct stream_t *stream) {
 				}
 
 				assert(free_worker_number >= 0);
-				assert(!pool.workers[free_worker_number].has_job);
+				assert(!atomic_load(&pool.workers[free_worker_number].has_job));
 
 				LOG_PERF("----- Raw frame dropped;  worker = %u", free_worker_number);
 			}
 
-			if (stream->proc->stop) {
+			if (atomic_load(&stream->proc->stop)) {
 				break;
 			}
 
-			if (stream->proc->slowdown) {
+			if (atomic_load(&stream->proc->slowdown)) {
 				usleep(1000000);
 			}
 
@@ -188,22 +186,23 @@ void stream_loop(struct stream_t *stream) {
 				if (FD_ISSET(stream->dev->run->fd, &read_fds)) {
 					LOG_DEBUG("Frame is ready");
 
-					struct v4l2_buffer buf_info;
+					int buf_index;
 					long double now = get_now_monotonic();
 					long long now_second = floor_ms(now);
 
-					if (_stream_grab_buffer(stream->dev, &buf_info) < 0) {
+					if ((buf_index = device_grab_buffer(stream->dev)) < 0) {
 						break;
 					}
-					stream->dev->run->pictures[buf_info.index].grab_time = now;
+					stream->dev->run->pictures[buf_index].grab_time = now;
 
 					// Workaround for broken, corrupted frames:
 					// Under low light conditions corrupted frames may get captured.
 					// The good thing is such frames are quite small compared to the regular pictures.
 					// For example a VGA (640x480) webcam picture is normally >= 8kByte large,
 					// corrupted frames are smaller.
-					if (buf_info.bytesused < stream->dev->min_frame_size) {
-						LOG_DEBUG("Dropping too small frame sized %u bytes, assuming it as broken", buf_info.bytesused);
+					if (stream->dev->run->hw_buffers[buf_index].used < stream->dev->min_frame_size) {
+						LOG_DEBUG("Dropping too small frame sized %zu bytes, assuming it as broken",
+							stream->dev->run->hw_buffers[buf_index].used);
 						goto pass_frame;
 					}
 
@@ -231,8 +230,7 @@ void stream_loop(struct stream_t *stream) {
 
 #					define FREE_WORKER(_next) pool.workers[free_worker_number]._next
 
-					LOG_DEBUG("Grabbed a new frame to buffer %u", buf_info.index);
-					FREE_WORKER(buf_info) = buf_info;
+					LOG_DEBUG("Grabbed a new frame to buffer %u", buf_index);
 
 					if (!oldest_worker) {
 						oldest_worker = &pool.workers[free_worker_number];
@@ -251,8 +249,8 @@ void stream_loop(struct stream_t *stream) {
 					last_worker->order_next = NULL;
 
 					A_MUTEX_LOCK(&FREE_WORKER(has_job_mutex));
-					FREE_WORKER(buf_index) = buf_info.index;
-					FREE_WORKER(has_job) = true;
+					FREE_WORKER(buf_index) = buf_index;
+					atomic_store(&FREE_WORKER(has_job), true);
 					A_MUTEX_UNLOCK(&FREE_WORKER(has_job_mutex));
 					A_COND_SIGNAL(&FREE_WORKER(has_job_cond));
 
@@ -266,7 +264,7 @@ void stream_loop(struct stream_t *stream) {
 
 					pass_frame:
 
-					if (_stream_release_buffer(stream->dev, &buf_info) < 0) {
+					if (device_release_buffer(stream->dev, buf_index) < 0) {
 						break;
 					}
 				}
@@ -280,7 +278,7 @@ void stream_loop(struct stream_t *stream) {
 
 				if (FD_ISSET(stream->dev->run->fd, &error_fds)) {
 					LOG_INFO("Got V4L2 event");
-					if (_stream_handle_event(stream->dev) < 0) {
+					if (device_consume_event(stream->dev) < 0) {
 						break;
 					}
 				}
@@ -288,25 +286,25 @@ void stream_loop(struct stream_t *stream) {
 		}
 
 		A_MUTEX_LOCK(&stream->mutex);
-		stream->picture.size = 0; // On stream offline
+		stream->picture.used = 0; // On stream offline
 		free(stream->picture.data);
 		stream->width = 0;
 		stream->height = 0;
-		stream->updated = true;
+		atomic_store(&stream->updated, true);
 		A_MUTEX_UNLOCK(&stream->mutex);
 	}
 
 	_stream_destroy_workers(stream, &pool);
-	_stream_control(stream->dev, false);
+	device_switch_capturing(stream->dev, false);
 	device_close(stream->dev);
 }
 
 void stream_loop_break(struct stream_t *stream) {
-	stream->proc->stop = 1;
+	atomic_store(&stream->proc->stop, true);
 }
 
 void stream_switch_slowdown(struct stream_t *stream, bool slowdown) {
-	stream->proc->slowdown = slowdown;
+	atomic_store(&stream->proc->slowdown, slowdown);
 }
 
 static void _stream_expose_picture(struct stream_t *stream, unsigned buf_index) {
@@ -314,10 +312,10 @@ static void _stream_expose_picture(struct stream_t *stream, unsigned buf_index)
 
 	A_MUTEX_LOCK(&stream->mutex);
 
-	stream->picture.size = PICTURE(size);
+	stream->picture.used = PICTURE(used);
 	stream->picture.allocated = PICTURE(allocated);
 
-	memcpy(stream->picture.data, PICTURE(data), stream->picture.size * sizeof(*stream->picture.data));
+	memcpy(stream->picture.data, PICTURE(data), stream->picture.used * sizeof(*stream->picture.data));
 
 	stream->picture.grab_time = PICTURE(grab_time);
 	stream->picture.encode_begin_time = PICTURE(encode_begin_time);
@@ -325,7 +323,7 @@ static void _stream_expose_picture(struct stream_t *stream, unsigned buf_index)
 
 	stream->width = stream->dev->run->width;
 	stream->height = stream->dev->run->height;
-	stream->updated = true;
+	atomic_store(&stream->updated, true);
 
 	A_MUTEX_UNLOCK(&stream->mutex);
 
@@ -365,8 +363,8 @@ static long double _stream_get_fluency_delay(struct device_t *dev, struct worker
 static int _stream_init_loop(struct stream_t *stream, struct workers_pool_t *pool) {
 	int retval = -1;
 
-	LOG_DEBUG("%s: *stream->proc->stop = %d", __FUNCTION__, stream->proc->stop);
-	while (!stream->proc->stop) {
+	LOG_DEBUG("%s: stream->proc->stop = %d", __FUNCTION__, atomic_load(&stream->proc->stop));
+	while (!atomic_load(&stream->proc->stop)) {
 		if ((retval = _stream_init(stream, pool)) < 0) {
 			LOG_INFO("Sleeping %u seconds before new stream init ...", stream->dev->error_delay);
 			sleep(stream->dev->error_delay);
@@ -381,13 +379,13 @@ static int _stream_init(struct stream_t *stream, struct workers_pool_t *pool) {
 	SEP_INFO('=');
 
 	_stream_destroy_workers(stream, pool);
-	_stream_control(stream->dev, false);
+	device_switch_capturing(stream->dev, false);
 	device_close(stream->dev);
 
 	if (device_open(stream->dev) < 0) {
 		goto error;
 	}
-	if (_stream_control(stream->dev, true) < 0) {
+	if (device_switch_capturing(stream->dev, true) < 0) {
 		goto error;
 	}
 
@@ -405,7 +403,7 @@ static int _stream_init(struct stream_t *stream, struct workers_pool_t *pool) {
 static void _stream_init_workers(struct stream_t *stream, struct workers_pool_t *pool) {
 	LOG_INFO("Spawning %u workers ...", stream->dev->n_workers);
 
-	*pool->workers_stop = false;
+	atomic_store(&pool->workers_stop, false);
 	A_CALLOC(pool->workers, stream->dev->n_workers);
 
 	A_MUTEX_INIT(&pool->free_workers_mutex);
@@ -417,11 +415,12 @@ static void _stream_init_workers(struct stream_t *stream, struct workers_pool_t
 		pool->free_workers += 1;
 
 		A_MUTEX_INIT(&WORKER(has_job_mutex));
+		atomic_init(&WORKER(has_job), false);
 		A_COND_INIT(&WORKER(has_job_cond));
 
 		WORKER(number)			= number;
-		WORKER(proc_stop)		= (sig_atomic_t *volatile)&(stream->proc->stop);
-		WORKER(workers_stop)	= pool->workers_stop;
+		WORKER(proc_stop)		= &stream->proc->stop;
+		WORKER(workers_stop)	= &pool->workers_stop;
 
 		WORKER(free_workers_mutex)	= &pool->free_workers_mutex;
 		WORKER(free_workers)		= &pool->free_workers;
@@ -441,13 +440,13 @@ static void *_stream_worker_thread(void *v_worker) {
 
 	LOG_DEBUG("Hello! I am a worker #%u ^_^", worker->number);
 
-	while (!*worker->proc_stop && !*worker->workers_stop) {
+	while (!atomic_load(worker->proc_stop) && !atomic_load(worker->workers_stop)) {
 		LOG_DEBUG("Worker %u waiting for a new job ...", worker->number);
 		A_MUTEX_LOCK(&worker->has_job_mutex);
-		A_COND_WAIT_TRUE(worker->has_job, &worker->has_job_cond, &worker->has_job_mutex);
+		A_COND_WAIT_TRUE(atomic_load(&worker->has_job), &worker->has_job_cond, &worker->has_job_mutex);
 		A_MUTEX_UNLOCK(&worker->has_job_mutex);
 
-		if (!*worker->workers_stop) {
+		if (!atomic_load(worker->workers_stop)) {
 #			define PICTURE(_next) worker->dev->run->pictures[worker->buf_index]._next
 
 			LOG_DEBUG("Worker %u compressing JPEG from buffer %u ...", worker->number, worker->buf_index);
@@ -458,9 +457,9 @@ static void *_stream_worker_thread(void *v_worker) {
 			}
 			PICTURE(encode_end_time) = get_now_monotonic();
 
-			if (_stream_release_buffer(worker->dev, &worker->buf_info) == 0) {
+			if (device_release_buffer(worker->dev, worker->buf_index) == 0) {
 				worker->job_start_time = PICTURE(encode_begin_time);
-				worker->has_job = false;
+				atomic_store(&worker->has_job, false);
 
 				long double last_comp_time = PICTURE(encode_end_time) - worker->job_start_time;
 
@@ -469,10 +468,10 @@ static void *_stream_worker_thread(void *v_worker) {
 				A_MUTEX_UNLOCK(&worker->last_comp_time_mutex);
 
 				LOG_VERBOSE("Compressed JPEG size=%zu; time=%0.3Lf; worker=%u; buffer=%u",
-					PICTURE(size), last_comp_time, worker->number, worker->buf_index);
+					PICTURE(used), last_comp_time, worker->number, worker->buf_index);
 			} else {
 				worker->job_failed = true;
-				worker->has_job = false;
+				atomic_store(&worker->has_job, false);
 			}
 
 #			undef PICTURE
@@ -492,12 +491,12 @@ static void _stream_destroy_workers(struct stream_t *stream, struct workers_pool
 	if (pool->workers) {
 		LOG_INFO("Destroying workers ...");
 
-		*pool->workers_stop = true;
+		atomic_store(&pool->workers_stop, true);
 		for (unsigned number = 0; number < stream->dev->n_workers; ++number) {
 #			define WORKER(_next) pool->workers[number]._next
 
 			A_MUTEX_LOCK(&WORKER(has_job_mutex));
-			WORKER(has_job) = true; // Final job: die
+			atomic_store(&WORKER(has_job), true); // Final job: die
 			A_MUTEX_UNLOCK(&WORKER(has_job_mutex));
 			A_COND_SIGNAL(&WORKER(has_job_cond));
 
@@ -516,68 +515,3 @@ static void _stream_destroy_workers(struct stream_t *stream, struct workers_pool
 	pool->free_workers = 0;
 	pool->workers = NULL;
 }
-
-static int _stream_control(struct device_t *dev, bool enable) {
-	if (enable != dev->run->capturing) {
-		enum v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-
-		LOG_DEBUG("Calling ioctl(%s) ...", (enable ? "VIDIOC_STREAMON" : "VIDIOC_STREAMOFF"));
-		if (xioctl(dev->run->fd, (enable ? VIDIOC_STREAMON : VIDIOC_STREAMOFF), &type) < 0) {
-			LOG_PERROR("Unable to %s capturing", (enable ? "start" : "stop"));
-			if (enable) {
-				return -1;
-			}
-		}
-
-		dev->run->capturing = enable;
-		LOG_INFO("Capturing %s", (enable ? "started" : "stopped"));
-	}
-    return 0;
-}
-
-static int _stream_grab_buffer(struct device_t *dev, struct v4l2_buffer *buf_info) {
-	MEMSET_ZERO_PTR(buf_info);
-	buf_info->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-	buf_info->memory = V4L2_MEMORY_MMAP;
-
-	LOG_DEBUG("Calling ioctl(VIDIOC_DQBUF) ...");
-	if (xioctl(dev->run->fd, VIDIOC_DQBUF, buf_info) < 0) {
-		LOG_PERROR("Unable to dequeue buffer");
-		return -1;
-	}
-
-	LOG_DEBUG("Got a new frame in buffer index=%u; bytesused=%u", buf_info->index, buf_info->bytesused);
-	if (buf_info->index >= dev->run->n_buffers) {
-		LOG_ERROR("Got invalid buffer index=%u; nbuffers=%u", buf_info->index, dev->run->n_buffers);
-		return -1;
-	}
-	return 0;
-}
-
-static int _stream_release_buffer(struct device_t *dev, struct v4l2_buffer *buf_info) {
-	LOG_DEBUG("Calling ioctl(VIDIOC_QBUF) ...");
-	if (xioctl(dev->run->fd, VIDIOC_QBUF, buf_info) < 0) {
-		LOG_PERROR("Unable to requeue buffer");
-		return -1;
-	}
-	return 0;
-}
-
-static int _stream_handle_event(struct device_t *dev) {
-	struct v4l2_event event;
-
-	LOG_DEBUG("Calling ioctl(VIDIOC_DQEVENT) ...");
-	if (!xioctl(dev->run->fd, VIDIOC_DQEVENT, &event)) {
-		switch (event.type) {
-			case V4L2_EVENT_SOURCE_CHANGE:
-				LOG_INFO("Got V4L2_EVENT_SOURCE_CHANGE: source changed");
-				return -1;
-			case V4L2_EVENT_EOS:
-				LOG_INFO("Got V4L2_EVENT_EOS: end of stream (ignored)");
-				return 0;
-		}
-	} else {
-		LOG_PERROR("Got some V4L2 device event, but where is it? ");
-	}
-	return 0;
-}

src/stream.h

@@ -23,7 +23,7 @@
 #pragma once
 
 #include <stdbool.h>
-#include <signal.h>
+#include <stdatomic.h>
 
 #include <pthread.h>
 
@@ -34,16 +34,15 @@
 struct worker_t {
 	pthread_t			tid;
 	unsigned			number;
-	sig_atomic_t		*volatile proc_stop;
-	bool				*workers_stop;
+	atomic_bool			*proc_stop;
+	atomic_bool			*workers_stop;
 
 	pthread_mutex_t		last_comp_time_mutex;
 	long double			last_comp_time;
 
 	pthread_mutex_t		has_job_mutex;
 	int					buf_index;
-	struct v4l2_buffer	buf_info;
-	bool				has_job;
+	atomic_bool			has_job;
 	bool				job_failed;
 	long double			job_start_time;
 	pthread_cond_t		has_job_cond;
@@ -61,7 +60,7 @@ struct worker_t {
 
 struct workers_pool_t {
 	struct worker_t		*workers;
-	bool				*workers_stop;
+	atomic_bool			workers_stop;
 
 	pthread_mutex_t		free_workers_mutex;
 	unsigned			free_workers;
@@ -71,8 +70,8 @@ struct workers_pool_t {
 };
 
 struct process_t {
-	sig_atomic_t volatile	stop;
-	bool					slowdown;
+	atomic_bool stop;
+	atomic_bool slowdown;
 };
 
 struct stream_t {
@@ -80,7 +79,7 @@ struct stream_t {
 	unsigned			width;
 	unsigned			height;
 	unsigned			captured_fps;
-	bool				updated;
+	atomic_bool			updated;
 	pthread_mutex_t		mutex;
 
 	struct process_t	*proc;

src/tools.h

@@ -51,7 +51,6 @@
 #define A_CALLOC(_dest, _nmemb)		assert((_dest = calloc(_nmemb, sizeof(*(_dest)))))
 #define A_REALLOC(_dest, _nmemb)	assert((_dest = realloc(_dest, _nmemb * sizeof(*(_dest)))))
 #define MEMSET_ZERO(_obj)			memset(&(_obj), 0, sizeof(_obj))
-#define MEMSET_ZERO_PTR(_ptr)		memset(_ptr, 0, sizeof(*(_ptr)))
 
 #define ARRAY_LEN(_array) (sizeof(_array) / sizeof(_array[0]))
 
@@ -63,12 +62,16 @@ INLINE char *bool_to_string(bool flag) {
 	return (flag ? "true" : "false");
 }
 
+INLINE unsigned min_u(unsigned a, unsigned b) {
+	return (a < b ? a : b);
+}
+
 INLINE unsigned max_u(unsigned a, unsigned b) {
 	return (a > b ? a : b);
 }
 
 INLINE long long floor_ms(long double now) {
-	return (long long) now - (now < (long long) now); // floor()
+	return (long long)now - (now < (long long)now); // floor()
 }
 
 INLINE void get_now(clockid_t clk_id, time_t *sec, long *msec) {