Added libevdev node

Makefile

@@ -1,4 +1,4 @@
-DEPS =
+DEPS = libevdev
 CFLAGS = -Wall -Wextra
 ifdef DEBUG
 	CFLAGS += -Og -gdwarf-2
@@ -10,7 +10,7 @@ CPPFLAGS += $(shell pkg-config --cflags $(DEPS))
 LDLIBS += $(shell pkg-config --libs $(DEPS))
 INTERP ?=
 MAIN = main
-OBJS = main.o events.o processing.o graph.o nodes/getchar.o nodes/print.o
+OBJS = main.o events.o processing.o graph.o nodes/getchar.o nodes/print.o nodes/evdev.o
 
 all: $(MAIN)
 

main.c

@@ -1,6 +1,7 @@
 #include "processing.h"
 #include "nodes/print.h"
 #include "nodes/getchar.h"
+#include "nodes/evdev.h"
 
 int
 main(int argc, char ** argv)
@@ -17,15 +18,19 @@ main(int argc, char ** argv)
 
 	GraphNode * input_node = graph_node_new(&nodespec_getchar);
 	GraphNode * output_node = graph_node_new(&nodespec_print);
-	GraphChannel chan;
-	graph_channel_init(&chan, input_node, 0, output_node, 0);
+	GraphNode * evdev_node = graph_node_new(&nodespec_evdev);
+	GraphChannel chan[2];
+	graph_channel_init(&chan[0], input_node, 0, output_node, 0);
+	graph_channel_init(&chan[1], evdev_node, 0, output_node, 1);
 	graph_node_register_io(input_node, &state);
 	graph_node_register_io(output_node, &state);
+	graph_node_register_io(evdev_node, &state);
 
 	while (true) {
 		process_iteration(&state);
 	}
 
+	graph_node_delete(evdev_node);
 	graph_node_delete(output_node);
 	graph_node_delete(input_node);
 

nodes/evdev.c

@@ -0,0 +1,129 @@
+#include <libevdev/libevdev.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdio.h>
+#include "evdev.h"
+#include "../processing.h"
+
+typedef struct {
+	GraphNode as_GraphNode;
+	IOHandling subscription;
+	struct libevdev *dev;
+	int fd;
+} EvdevGraphNode;
+
+static void
+handle_io(EventPositionBase * self, int fd, bool is_output)
+{
+	(void) is_output;
+	(void) fd;
+	EvdevGraphNode * node = DOWNCAST(EvdevGraphNode, GraphNode, DOWNCAST(GraphNode, EventPositionBase, self));
+	int err = 0;
+	AbsoluteTime realtime;
+	clock_gettime(CLOCK_REALTIME, &realtime.absolute);
+	AbsoluteTime monotime = get_current_time();
+	RelativeTime realtime_adj = absolute_time_sub_absolute(realtime, monotime);
+	while (!err) {
+		struct input_event buf;
+		err = libevdev_next_event(node->dev, LIBEVDEV_READ_FLAG_NORMAL, &buf);
+		if (err) {
+			if (err == -EAGAIN || err == 1) {
+				break;
+			}
+			node->subscription.enabled = false;
+			if (err < 0) {
+				errno = -err;
+				perror("Failed to read evdev event");
+			}
+			break;
+		}
+		realtime.absolute.tv_sec = buf.time.tv_sec;
+		realtime.absolute.tv_nsec = buf.time.tv_usec * (long) 1000;
+		monotime = absolute_time_sub_relative(realtime, realtime_adj);
+		EventData data = {
+			.code = {
+				.ns = 1,
+				.value = (((int32_t) buf.type) << 16) | buf.code,
+			},
+			.ttl = 100,
+			.priority = 10,
+			.payload = buf.value,
+			.modifiers = EMPTY_MODIFIER_SET,
+			.time = monotime,
+		};
+		for (size_t i = 0; i < node->as_GraphNode.outputs.length; ++i) {
+			EventNode *ev = event_create(&data);
+			if (!ev) {
+				perror("Failed to create event");
+				break;
+			}
+			ev->position = &node->as_GraphNode.outputs.elements[i]->as_EventPositionBase;
+		}
+	}
+}
+
+static GraphNode *
+create(GraphNodeSpecification * spec)
+{
+	EvdevGraphNode * node = calloc(1, sizeof(EvdevGraphNode));
+	if (!node) {
+		return NULL;
+	}
+	int fd = open("/dev/input/event7", O_RDONLY | O_NONBLOCK);
+	int err;
+	if ((err = libevdev_new_from_fd(fd, &node->dev)) < 0) {
+		errno = -err;
+		free(node);
+		return NULL;
+	}
+	*node = (EvdevGraphNode) {
+		.as_GraphNode = {
+			.as_EventPositionBase = {
+				.handle_event = NULL,
+				.waiting_new_event = false,
+			},
+			.specification = spec,
+			.inputs = EMPTY_GRAPH_CHANNEL_LIST,
+			.outputs = EMPTY_GRAPH_CHANNEL_LIST,
+		},
+		.subscription = {
+			.self = &node->as_GraphNode.as_EventPositionBase,
+			.handle_io = handle_io,
+			.enabled = true,
+		},
+		.dev = node->dev,
+		.fd = fd,
+	};
+	return &node->as_GraphNode;
+}
+
+static void destroy
+(GraphNodeSpecification * self, GraphNode * target)
+{
+	(void) self;
+	EvdevGraphNode * node = DOWNCAST(EvdevGraphNode, GraphNode, target);
+	if (node->dev) {
+		libevdev_free(node->dev);
+		node->dev = NULL;
+		close(node->fd);
+	}
+	free(target);
+}
+
+static void
+register_io(GraphNodeSpecification * self, GraphNode * target, ProcessingState * state)
+{
+	(void) self;
+	EvdevGraphNode * node = DOWNCAST(EvdevGraphNode, GraphNode, target);
+	io_subscription_list_add(&state->wait_input, node->fd, &node->subscription);
+}
+
+GraphNodeSpecification nodespec_evdev = (GraphNodeSpecification) {
+	.create = &create,
+	.destroy = &destroy,
+	.register_io = &register_io,
+	.name = "evdev",
+};

nodes/evdev.h

@@ -0,0 +1,8 @@
+#ifndef NODES_EVDEV_H_
+#define NODES_EVDEV_H_
+
+#include "../graph.h"
+
+extern GraphNodeSpecification nodespec_evdev;
+
+#endif /* end of include guard: NODES_EVDEV_H_ */