Create separate input module

build.sh

@@ -8,4 +8,4 @@ defs="-D_POSIX_C_SOURCE=200809L"
 
 $cc $flags $libs $defs \
 	-o asteroids \
-	fb.c main.c renderer.c
+	fb.c input.c main.c renderer.c

input.c

@@ -0,0 +1,56 @@
+#include "input.h"
+
+#include <assert.h>
+#include <fcntl.h>
+#include <linux/input.h>
+#include <string.h>
+#include <unistd.h>
+
+enum {
+	RELEASE = 0,
+	PRESS = 1,
+	REPEAT = 2,
+	NCALLBACKS,
+};
+
+static int input_fd;
+static input_callback_t callbacks[NCALLBACKS];
+
+int input_init()
+{
+	input_fd = open("/dev/input/event0", O_RDONLY);
+	assert(input_fd != -1);
+	memset(callbacks, 0, sizeof(callbacks));
+	return input_fd;
+}
+
+void input_cleanup()
+{
+	close(input_fd);
+}
+
+void input_on_press(input_callback_t cb)
+{
+	callbacks[PRESS] = cb;
+}
+
+void input_on_release(input_callback_t cb)
+{
+	callbacks[RELEASE] = cb;
+}
+
+void input_on_repeat(input_callback_t cb)
+{
+	callbacks[REPEAT] = cb;
+}
+
+void input_handle()
+{
+	struct input_event ev;
+	const int len = read(input_fd, &ev, sizeof(ev));
+	assert(len == sizeof(ev));
+	if (ev.type == EV_KEY && 0 <= ev.value && ev.value < NCALLBACKS) {
+		if (callbacks[ev.value] != nullptr)
+			callbacks[ev.value](ev.code);
+	}
+}

input.h

@@ -0,0 +1,15 @@
+#ifndef INPUT_H
+#define INPUT_H
+
+typedef void (*input_callback_t)(int key);
+
+int input_init();
+void input_cleanup();
+
+void input_on_press(input_callback_t cb);
+void input_on_release(input_callback_t cb);
+void input_on_repeat(input_callback_t cb);
+
+void input_handle();
+
+#endif

main.c

@@ -1,46 +1,47 @@
+#include "input.h"
 #include "renderer.h"
 
-#include <assert.h>
-#include <fcntl.h>
-#include <linux/input.h>
+#include <linux/input-event-codes.h>
 #include <sys/select.h>
-#include <unistd.h>
 
 #define MAX(a, b) ((a) < (b) ? (b) : (a))
 
+static bool quit = false;
+
+static void key_press_callback(int key)
+{
+	switch (key) {
+	case KEY_Q:
+		quit = true;
+		break;
+
+	default:
+		break;
+	}
+}
+
 int main()
 {
-	int err;
-
-	const int input_fd = open("/dev/input/event0", O_RDONLY);
-	assert(input_fd != -1);
+	const int input_fd = input_init();
+	input_on_press(key_press_callback);
 
 	const renderer_params_t renderer_params = renderer_init();
 	const int drm_fd = renderer_params.drm_fd;
-
 	renderer_clear();
 	renderer_swap();
 
 	const int max_fd = MAX(input_fd, drm_fd);
 	fd_set set;
-	bool running = true;
-	while (running) {
+
+	while (!quit) {
 		FD_ZERO(&set);
 		FD_SET(input_fd, &set);
 		FD_SET(drm_fd, &set);
 
 		select(max_fd + 1, &set, nullptr, nullptr, nullptr);
 
-		if (FD_ISSET(input_fd, &set)) {
-			struct input_event ev;
-			const int len = read(input_fd, &ev, sizeof(ev));
-			assert(len == sizeof(ev));
-
-			if (ev.type == EV_KEY && ev.value >= 0 && ev.value <= 2) {
-				if (ev.code == KEY_Q && ev.value == 1)
-					running = false;
-			}
-		}
+		if (FD_ISSET(input_fd, &set))
+			input_handle();
 
 		if (FD_ISSET(drm_fd, &set)) {
 			renderer_handle();
@@ -50,7 +51,7 @@ int main()
 	}
 
 	renderer_cleanup();
-	close(input_fd);
+	input_cleanup();
 
 	return 0;
 }