Drop from_fd, replace with from_udev_device

We don't need the evdev fd, it's more flexible to start with a udev device.
This changes ratbag-command to take a /sys path as well, but for not it'll
do.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

src/libratbag-private.h

@@ -43,7 +43,6 @@ struct ratbag {
 	char *name;
 	struct udev_device *udev_device;
 	struct udev_device *udev_hidraw;
-	int evdev_fd;
 	int hidraw_fd;
 	int refcount;
 	struct input_id ids;
@@ -103,8 +102,6 @@ struct ratbag_button {
 	enum ratbag_button_action_type action_type;
 };
 
-void ratbag_device_init(struct ratbag *rb, int fd);
-
 static inline void
 ratbag_set_drv_data(struct ratbag *ratbag, void *drv_data)
 {

src/libratbag-util.c

@@ -69,3 +69,19 @@ list_empty(const struct list *list)
 {
 	return list->next == list;
 }
+
+const char *
+udev_prop_value(struct udev_device *device,
+		const char *prop_name)
+{
+	struct udev_device *parent;
+	const char *prop_value = NULL;
+
+	parent = device;
+	while (parent && !prop_value) {
+		prop_value = udev_device_get_property_value(parent, prop_name);
+		parent = udev_device_get_parent(parent);
+	}
+
+	return prop_value;
+}

src/libratbag-util.h

@@ -25,6 +25,7 @@
 #define LIBRATBAG_UTIL_H
 
 #include <unistd.h>
+#include <libudev.h>
 
 /*
  * This list data structure is a verbatim copy from wayland-util.h from the
@@ -117,4 +118,7 @@ long_set_bit_state(unsigned long *array, int bit, int state)
 		long_clear_bit(array, bit);
 }
 
+const char *
+udev_prop_value(struct udev_device *device,
+		const char *property_name);
 #endif /* LIBRATBAG_UTIL_H */

src/libratbag.c

@@ -158,17 +158,12 @@ out:
 }
 
 static int
-ratbag_device_init_udev(struct libratbag *libratbag, struct ratbag *ratbag, int fd)
+ratbag_device_init_udev(struct libratbag *libratbag, struct ratbag *ratbag,
+			struct udev_device *udev_device)
 {
-	struct udev_device *udev_device;
 	struct udev_device *hidraw_udev;
 	int rc = -ENODEV;
 
-	udev_device = udev_device_from_devnode(libratbag, ratbag, fd);
-	if (!udev_device) {
-		log_bug_client(libratbag, "Invalid path %s\n", fd);
-		return -ENODEV;
-	}
 	ratbag->udev_device = udev_device_ref(udev_device);
 
 	hidraw_udev = udev_find_hidraw(libratbag, ratbag);
@@ -188,10 +183,9 @@ out:
 	return rc;
 }
 
-void
-ratbag_device_init(struct ratbag *rb, int fd)
+static void
+ratbag_device_init(struct ratbag *rb)
 {
-	rb->evdev_fd = fd;
 	rb->hidraw_fd = -1;
 	rb->refcount = 1;
 	list_init(&rb->profiles);
@@ -243,13 +237,46 @@ ratbag_find_driver(struct libratbag *libratbag, struct ratbag *ratbag,
 	return NULL;
 }
 
+static inline char*
+get_device_name(struct udev_device *device)
+{
+	const char *prop;
+
+	prop = udev_prop_value(device, "NAME");
+	if (!prop)
+		return NULL;
+
+	/* udev name is inclosed by " */
+	return strndup(&prop[1], strlen(prop) - 2);
+}
+
+static inline int
+get_product_id(struct udev_device *device, struct input_id *id)
+{
+	const char *product;
+	struct input_id ids;
+	int rc;
+
+	product = udev_prop_value(device, "PRODUCT");
+	if (!product)
+		return -1;
+
+	rc = sscanf(product, "%hx/%hx/%hx/%hx", &ids.bustype,
+		    &ids.vendor, &ids.product, &ids.version);
+	if (rc != 4)
+		return -1;
+
+	*id = ids;
+	return 0;
+}
+
 LIBRATBAG_EXPORT struct ratbag*
-ratbag_new_from_fd(struct libratbag *libratbag, int fd)
+ratbag_new_from_udev_device(struct libratbag *libratbag,
+			    struct udev_device *device)
 {
 	int rc;
 	struct ratbag *ratbag = NULL;
 	struct ratbag_driver *driver;
-	char buf[256];
 
 	if (!libratbag) {
 		fprintf(stderr, "libratbag is NULL\n");
@@ -261,25 +288,17 @@ ratbag_new_from_fd(struct libratbag *libratbag, int fd)
 		return NULL;
 
 	ratbag->libratbag = libratbag_ref(libratbag);
-
-	rc = ioctl(fd, EVIOCGID, &ratbag->ids);
-	if (rc < 0)
+	if (get_product_id(device, &ratbag->ids) != 0)
 		goto out_err;
-
-	memset(buf, 0, sizeof(buf));
-	rc = ioctl(fd, EVIOCGNAME(sizeof(buf) - 1), buf);
-	if (rc < 0)
-		goto out_err;
-
 	free(ratbag->name);
-	ratbag->name = strdup(buf);
+	ratbag->name = get_device_name(device);
 	if (!ratbag->name) {
 		errno = ENOMEM;
 		goto out_err;
 	}
 
-	ratbag_device_init(ratbag, fd);
-	rc = ratbag_device_init_udev(libratbag, ratbag, fd);
+	ratbag_device_init(ratbag);
+	rc = ratbag_device_init_udev(libratbag, ratbag, device);
 	if (rc)
 		goto out_err;
 

src/libratbag.h

@@ -30,6 +30,7 @@ extern "C" {
 
 #include <stdlib.h>
 #include <stdarg.h>
+#include <libudev.h>
 
 #define LIBRATBAG_ATTRIBUTE_PRINTF(_format, _args) \
 	__attribute__ ((format (printf, _format, _args)))
@@ -169,11 +170,11 @@ libratbag_unref(struct libratbag *libratbag);
 /**
  * @ingroup base
  *
- * Create a new ratbag context from the given fd. The file descriptor must
- * point to a /dev/input/eventX event node and be opened in O_RDWR.
+ * Create a new ratbag context from the given udev device.
  */
 struct ratbag*
-ratbag_new_from_fd(struct libratbag *libratbag, int fd);
+ratbag_new_from_udev_device(struct libratbag *libratbag,
+			    struct udev_device *device);
 
 /**
  * @ingroup base

src/libratbag.sym

@@ -14,7 +14,7 @@ global:
 	ratbag_get_num_buttons;
 	ratbag_get_profile_by_index;
 	ratbag_has_capability;
-	ratbag_new_from_fd;
+	ratbag_new_from_udev_device;
 	ratbag_set_active_profile;
 	ratbag_profile_ref;
 	ratbag_profile_unref;

tools/ratbag-command.c

@@ -33,7 +33,7 @@
 static void
 list_ratbags_usage(void)
 {
-	printf("Usage: %s [options] /dev/input/eventX\n"
+	printf("Usage: %s [options] /sys/class/input/eventX\n"
 	       "/path/to/device .... open the given device only\n"
 	       "\n"
 	       "Features:\n"
@@ -52,9 +52,10 @@ main(int argc, char **argv)
 	struct ratbag_profile *profile;
 	struct ratbag_button *button;
 	char *path;
-	int fd;
 	int i;
 	int retval = 0;
+	struct udev *udev;
+	struct udev_device *udev_device;
 
 	if (argc < 2) {
 		list_ratbags_usage();
@@ -62,8 +63,9 @@ main(int argc, char **argv)
 	}
 
 	path = argv[1];
-	fd = open(path, O_RDWR);
-	if (fd <= 0) {
+	udev = udev_new();
+	udev_device = udev_device_new_from_syspath(udev, path);
+	if (!udev_device) {
 		fprintf(stderr, "Can't open '%s': %s\n", path, strerror(errno));
 		return 1;
 	}
@@ -74,7 +76,7 @@ main(int argc, char **argv)
 		return 1;
 	}
 
-	rb = ratbag_new_from_fd(libratbag, fd);
+	rb = ratbag_new_from_udev_device(libratbag, udev_device);
 
 	if (!rb) {
 		fprintf(stderr, "Looks like '%s' is not supported\n", path);
@@ -98,6 +100,6 @@ main(int argc, char **argv)
 out:
 	rb = ratbag_unref(rb);
 	libratbag_unref(libratbag);
-	close(fd);
+	udev_unref(udev);
 	return retval;
 }