Switch the buttons to a GHashTable

Slightly simpler to manage, we keep a hashtable around with the alphabetic
button as key and a new struct with flags + code as value. This removes the
need for all the seperate array + length tracking.

Minor regression: a caller passing invalid button codes will simply return the
zero values now, without a glib error message.

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

3 files changed, 137 insertions, 95 deletions

diff --git a/libwacom/libwacom-database.c b/libwacom/libwacom-database.c
index d3c2366..569b0d5 100644
--- a/libwacom/libwacom-database.c
+++ b/libwacom/libwacom-database.c
@@ -422,6 +422,7 @@ libwacom_parse_buttons_key(WacomDevice      *device,
 		return;
 	for (i = 0; vals[i] != NULL; i++) {
 		char val;
+		WacomButton *button;
 
 		val = *vals[i];
 		if (strlen (vals[i]) > 1 ||
@@ -430,85 +431,118 @@ libwacom_parse_buttons_key(WacomDevice      *device,
 			g_warning ("Ignoring value '%s' in key '%s'", vals[i], key);
 			continue;
 		}
-		val -= 'A';
-		device->buttons[(int) val] |= flag;
+
+		button = g_hash_table_lookup(device->buttons, GINT_TO_POINTER(val));
+		if (!button) {
+			button = g_new0(WacomButton, 1);
+			g_hash_table_insert(device->buttons, GINT_TO_POINTER(val), button);
+		}
+
+		button->flags |= flag;
 	}
 
 	g_strfreev (vals);
 }
 
+static void
+reset_code(gpointer key, gpointer value, gpointer user_data)
+{
+	WacomButton *button = value;
+	button->code = 0;
+}
+
 static inline bool
 set_button_codes_from_string(WacomDevice *device, char **strvals)
 {
-	gint i;
+	bool success = false;
 
 	assert(strvals);
 
-	for (i = 0; i < device->num_buttons; i++) {
-		gint val;
+	for (guint i = 0; i < g_hash_table_size(device->buttons); i++) {
+		char key = 'A' + i;
+		int code;
+		WacomButton *button = g_hash_table_lookup(device->buttons, GINT_TO_POINTER(key));
+
+		if (!button) {
+			g_error("%s: Button %c is not defined, ignoring all codes\n",
+				device->name, key);
+			goto out;
+		}
 
 		if (!strvals[i]) {
 			g_error ("%s: Missing EvdevCode for button %d, ignoring all codes\n",
 				 device->name, i);
-			return false;
+			goto out;
 		}
 
-		if (!safe_atoi_base (strvals[i], &val, 16) || val < BTN_MISC || val >= BTN_DIGI) {
-			g_warning ("%s: Invalid EvdevCode %s for button %d, ignoring all codes\n",
-				   device->name, strvals[i], i);
-			return false;
+		if (!safe_atoi_base (strvals[i], &code, 16) || code < BTN_MISC || code >= BTN_DIGI) {
+			g_warning ("%s: Invalid EvdevCode %s for button %c, ignoring all codes\n",
+				   device->name, strvals[i], key);
+			goto out;
 		}
-		device->button_codes[i] = val;
+		button->code = code;
 	}
+	success = true;
 
-	return true;
+out:
+	if (!success)
+		g_hash_table_foreach(device->buttons, reset_code, NULL);
+
+	return success;
 }
 
 static inline void
 set_button_codes_from_heuristics(WacomDevice *device)
 {
-	gint i;
-	for (i = 0; i < device->num_buttons; i++) {
+	for (char key = 'A'; key <= 'Z'; key++) {
+		int code = 0;
+		WacomButton *button;
+
+		button = g_hash_table_lookup(device->buttons, GINT_TO_POINTER(key));
+		if (!button)
+			continue;
+
 		if (device->cls == WCLASS_BAMBOO ||
 		    device->cls == WCLASS_GRAPHIRE) {
-			switch (i) {
-			case 0:
-				device->button_codes[i] = BTN_LEFT;
-				break;
-			case 1:
-				device->button_codes[i] = BTN_RIGHT;
-				break;
-			case 2:
-				device->button_codes[i] = BTN_FORWARD;
-				break;
-			case 3:
-				device->button_codes[i] = BTN_BACK;
-				break;
+			switch (key) {
+			case 'A': code = BTN_LEFT; break;
+			case 'B': code = BTN_RIGHT; break;
+			case 'C': code = BTN_FORWARD; break;
+			case 'D': code = BTN_BACK; break;
 			default:
-				device->button_codes[i] = 0;
 				break;
 			}
 		} else {
 			/* Assume traditional ExpressKey ordering */
-			switch (i) {
-			case 0 ... 9:
-				device->button_codes[i] = BTN_0 + i;
-				break;
-			case 10 ... 15:
-				device->button_codes[i] = BTN_A + (i-10);
-				break;
-			case 16:
-			case 17:
-				device->button_codes[i] = BTN_BASE + (i-16);
-				break;
+			switch (key) {
+			case 'A': code = BTN_0; break;
+			case 'B': code = BTN_1; break;
+			case 'C': code = BTN_2; break;
+			case 'D': code = BTN_3; break;
+			case 'E': code = BTN_4; break;
+			case 'F': code = BTN_5; break;
+			case 'G': code = BTN_6; break;
+			case 'H': code = BTN_7; break;
+			case 'I': code = BTN_8; break;
+			case 'J': code = BTN_9; break;
+			case 'K': code = BTN_A; break;
+			case 'L': code = BTN_B; break;
+			case 'M': code = BTN_C; break;
+			case 'N': code = BTN_X; break;
+			case 'O': code = BTN_Y; break;
+			case 'P': code = BTN_Z; break;
+			case 'Q': code = BTN_BASE; break;
+			case 'R': code = BTN_BASE2; break;
 			default:
-				device->button_codes[i] = 0;
 				break;
 			}
 		}
 
-		if (device->button_codes[i] == 0)
-			g_warning ("Unable to determine evdev code for button %d (%s)", i, device->name);
+		if (code == 0)
+			g_warning ("Unable to determine evdev code for button %c (%s)",
+				   key, device->name);
+
+		button->code = code;
 	}
 }
 
@@ -519,8 +553,7 @@ libwacom_parse_button_codes(WacomDevice *device,
 	char **vals;
 
 	vals = g_key_file_get_string_list(keyfile, BUTTONS_GROUP, "EvdevCodes", NULL, NULL);
-	if (!vals ||
-	    !set_button_codes_from_string(device, vals))
+	if (!vals || !set_button_codes_from_string(device, vals))
 		set_button_codes_from_heuristics(device);
 
 	g_strfreev (vals);
@@ -532,16 +565,21 @@ libwacom_parse_num_modes (WacomDevice      *device,
 			  const char       *key,
 			  WacomButtonFlags  flag)
 {
+	GHashTableIter iter;
 	int num;
-	int i;
+	gpointer k, v;
 
 	num = g_key_file_get_integer (keyfile, BUTTONS_GROUP, key, NULL);
 	if (num > 0)
 		return num;
-	for (i = 0; i < device->num_buttons; i++) {
-		if (device->buttons[i] & flag)
+
+	g_hash_table_iter_init(&iter, device->buttons);
+	while (g_hash_table_iter_next(&iter, &k, &v)) {
+		WacomButton *button = v;
+		if (button->flags & flag)
 			num++;
 	}
+
 	return num;
 }
 
@@ -621,6 +659,7 @@ libwacom_parse_tablet_keyfile(WacomDeviceDatabase *db,
 	char *paired;
 	char **string_list;
 	bool success = FALSE;
+	int num_buttons;
 
 	keyfile = g_key_file_new();
 
@@ -760,17 +799,18 @@ libwacom_parse_tablet_keyfile(WacomDeviceDatabase *db,
 		g_warning ("Tablet '%s' has touch switch but no touch tool. This is impossible", libwacom_get_match(device));
 
 	device->num_strips = g_key_file_get_integer(keyfile, FEATURES_GROUP, "NumStrips", NULL);
-	device->num_buttons = g_key_file_get_integer(keyfile, FEATURES_GROUP, "Buttons", &error);
-	if (device->num_buttons == 0 &&
+
+	num_buttons = g_key_file_get_integer(keyfile, FEATURES_GROUP, "Buttons", &error);
+	if (num_buttons == 0 &&
 	    g_error_matches (error, G_KEY_FILE_ERROR, G_KEY_FILE_ERROR_KEY_NOT_FOUND)) {
 		g_warning ("Tablet '%s' has no buttons defined, do something!", libwacom_get_match(device));
 		g_clear_error (&error);
 	}
-	if (device->num_buttons > 0) {
-		device->buttons = g_new0 (WacomButtonFlags, device->num_buttons);
-		device->button_codes = g_new0 (gint, device->num_buttons);
+
+	device->buttons = g_hash_table_new_full(g_direct_hash, g_direct_equal,
+						NULL, g_free);
+	if (num_buttons > 0)
 		libwacom_parse_buttons(device, keyfile);
-	}
 
 	string_list = g_key_file_get_string_list(keyfile, FEATURES_GROUP, "StatusLEDs", NULL, NULL);
 	if (string_list) {
diff --git a/libwacom/libwacom.c b/libwacom/libwacom.c
index b151fb3..9f6aa0d 100644
--- a/libwacom/libwacom.c
+++ b/libwacom/libwacom.c
@@ -311,6 +311,8 @@ static WacomDevice *
 libwacom_copy(const WacomDevice *device)
 {
 	WacomDevice *d;
+	GHashTableIter iter;
+	gpointer k, v;
 
 	d = g_new0 (WacomDevice, 1);
 	g_atomic_int_inc(&d->refcnt);
@@ -343,10 +345,16 @@ libwacom_copy(const WacomDevice *device)
 		g_array_append_val(d->styli, id);
 	}
 	d->num_leds = device->num_leds;
-	d->status_leds = g_memdup2 (device->status_leds, sizeof(WacomStatusLEDs) * device->num_leds);
-	d->num_buttons = device->num_buttons;
-	d->buttons = g_memdup2 (device->buttons, sizeof(WacomButtonFlags) * device->num_buttons);
-	d->button_codes = g_memdup2 (device->button_codes, sizeof(int) * device->num_buttons);
+	d->status_leds = g_memdup2(device->status_leds, sizeof(WacomStatusLEDs) * device->num_leds);
+
+	d->buttons = g_hash_table_new_full(g_direct_hash, g_direct_equal,
+					   NULL, g_free);
+	g_hash_table_iter_init(&iter, device->buttons);
+	while (g_hash_table_iter_next(&iter, &k, &v)) {
+		WacomButton *a = v;
+		WacomButton *b = g_memdup2(a, sizeof(WacomButton));
+		g_hash_table_insert(d->buttons, k, b);
+	}
 	return d;
 }
 
@@ -401,6 +409,9 @@ libwacom_same_layouts (const WacomDevice *a, const WacomDevice *b)
 LIBWACOM_EXPORT int
 libwacom_compare(const WacomDevice *a, const WacomDevice *b, WacomCompareFlags flags)
 {
+	GHashTableIter iter;
+	gpointer k, v;
+
 	g_return_val_if_fail(a || b, 0);
 
 	if (!a || !b)
@@ -439,7 +450,7 @@ libwacom_compare(const WacomDevice *a, const WacomDevice *b, WacomCompareFlags f
 	if (a->ring2_num_modes != b->ring2_num_modes)
 		return 1;
 
-	if (a->num_buttons != b->num_buttons)
+	if (g_hash_table_size(a->buttons) != g_hash_table_size(b->buttons))
 		return 1;
 
 	if (a->styli->len != b->styli->len)
@@ -454,11 +465,14 @@ libwacom_compare(const WacomDevice *a, const WacomDevice *b, WacomCompareFlags f
 	if (memcmp(a->status_leds, b->status_leds, sizeof(WacomStatusLEDs) * a->num_leds) != 0)
 		return 1;
 
-	if (memcmp(a->buttons, b->buttons, sizeof(WacomButtonFlags) * a->num_buttons) != 0)
-		return 1;
+	g_hash_table_iter_init(&iter, a->buttons);
+	while (g_hash_table_iter_next(&iter, &k, &v)) {
+		WacomButton *ba = v;
+		WacomButton *bb = g_hash_table_lookup(b->buttons, k);
 
-	if (memcmp(a->button_codes, b->button_codes, sizeof(int) * a->num_buttons) != 0)
-		return 1;
+		if (!bb || ba->flags != bb->flags || ba->code != bb->code)
+			return 1;
+	}
 
 	if ((a->paired == NULL && b->paired != NULL) ||
 	    (a->paired != NULL && b->paired == NULL) ||
@@ -880,8 +894,8 @@ libwacom_unref(WacomDevice *device)
 	g_array_free (device->matches, TRUE);
 	g_array_free (device->styli, TRUE);
 	g_free (device->status_leds);
-	g_free (device->buttons);
-	g_free (device->button_codes);
+	if (device->buttons)
+		g_hash_table_destroy (device->buttons);
 	g_free (device);
 
 	return NULL;
@@ -1048,7 +1062,7 @@ libwacom_has_touch(const WacomDevice *device)
 LIBWACOM_EXPORT int
 libwacom_get_num_buttons(const WacomDevice *device)
 {
-	return device->num_buttons;
+	return g_hash_table_size(device->buttons);
 }
 
 LIBWACOM_EXPORT const int *
@@ -1114,24 +1128,18 @@ struct {
 LIBWACOM_EXPORT int
 libwacom_get_button_led_group (const WacomDevice *device, char button)
 {
-	int button_index, led_index;
-	WacomButtonFlags button_flags;
-
-	g_return_val_if_fail (device->num_buttons > 0, -1);
-	g_return_val_if_fail (button >= 'A', -1);
-	g_return_val_if_fail (button < 'A' + device->num_buttons, -1);
-
-	button_index = button - 'A';
-	button_flags = device->buttons[button_index];
+	int led_index;
+	WacomButton *b = g_hash_table_lookup(device->buttons,
+					     GINT_TO_POINTER(button));
 
-	if (!(button_flags & WACOM_BUTTON_MODESWITCH))
+	if (!(b->flags & WACOM_BUTTON_MODESWITCH))
 		return -1;
 
 	for (led_index = 0; led_index < device->num_leds; led_index++) {
 		guint n;
 
 		for (n = 0; n < G_N_ELEMENTS (button_status_leds); n++) {
-			if ((button_flags & button_status_leds[n].button_flags) &&
+			if ((b->flags & button_status_leds[n].button_flags) &&
 			    (device->status_leds[led_index] == button_status_leds[n].status_leds)) {
 				return led_index;
 			}
@@ -1179,29 +1187,20 @@ libwacom_get_bustype(const WacomDevice *device)
 LIBWACOM_EXPORT WacomButtonFlags
 libwacom_get_button_flag(const WacomDevice *device, char button)
 {
-	int index;
+	WacomButton *b = g_hash_table_lookup(device->buttons,
+					     GINT_TO_POINTER(button));
 
-	g_return_val_if_fail (device->num_buttons > 0, WACOM_BUTTON_NONE);
-	g_return_val_if_fail (button >= 'A', WACOM_BUTTON_NONE);
-	g_return_val_if_fail (button < 'A' + device->num_buttons, WACOM_BUTTON_NONE);
 
-	index = button - 'A';
-
-	return device->buttons[index];
+	return b ? b->flags : WACOM_BUTTON_NONE;
 }
 
 LIBWACOM_EXPORT int
 libwacom_get_button_evdev_code(const WacomDevice *device, char button)
 {
-	int index;
-
-	g_return_val_if_fail (device->num_buttons > 0, 0);
-	g_return_val_if_fail (button >= 'A', 0);
-	g_return_val_if_fail (button < 'A' + device->num_buttons, 0);
-
-	index = button - 'A';
+	WacomButton *b = g_hash_table_lookup(device->buttons,
+					     GINT_TO_POINTER(button));
 
-	return device->button_codes[index];
+	return b ? b->code : 0;
 }
 
 LIBWACOM_EXPORT const
diff --git a/libwacom/libwacomint.h b/libwacom/libwacomint.h
index f5041a2..47574b0 100644
--- a/libwacom/libwacomint.h
+++ b/libwacom/libwacomint.h
@@ -61,6 +61,12 @@ struct _WacomMatch {
 	uint32_t product_id;
 };
 
+/* Used in the device->buttons hashtable */
+typedef struct _WacomButton {
+	WacomButtonFlags flags;
+	int code;
+} WacomButton;
+
 /* WARNING: When adding new members to this struct
  * make sure to update libwacom_copy() and
  * libwacom_print_device_description() ! */
@@ -85,10 +91,7 @@ struct _WacomDevice {
 	int ring2_num_modes;
 
 	GArray *styli;
-
-	int num_buttons;
-	WacomButtonFlags *buttons;
-	int *button_codes;
+	GHashTable *buttons; /* 'A' : WacomButton */
 
 	int num_leds;
 	WacomStatusLEDs *status_leds;