1 files changed, 232 insertions, 0 deletions
diff --git a/sway/desktop/transaction.c b/sway/desktop/transaction.c
new file mode 100644
index 00000000..07bfbf7a
--- /dev/null
+++ b/sway/desktop/transaction.c
@@ -0,0 +1,232 @@
+#define _POSIX_C_SOURCE 200809L
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <wlr/types/wlr_linux_dmabuf.h>
+#include "sway/debug.h"
+#include "sway/desktop/transaction.h"
+#include "sway/output.h"
+#include "sway/tree/container.h"
+#include "sway/tree/view.h"
+#include "list.h"
+#include "log.h"
+
+/**
+ * How long we should wait for views to respond to the configure before giving
+ * up and applying the transaction anyway.
+ */
+#define TIMEOUT_MS 200
+
+struct sway_transaction {
+	struct wl_event_source *timer;
+	list_t *instructions;   // struct sway_transaction_instruction *
+	list_t *damage;         // struct wlr_box *
+	size_t num_waiting;
+};
+
+struct sway_transaction_instruction {
+	struct sway_transaction *transaction;
+	struct sway_container *container;
+	struct sway_container_state state;
+	uint32_t serial;
+};
+
+struct sway_transaction *transaction_create() {
+	struct sway_transaction *transaction =
+		calloc(1, sizeof(struct sway_transaction));
+	transaction->instructions = create_list();
+	transaction->damage = create_list();
+	return transaction;
+}
+
+static void transaction_destroy(struct sway_transaction *transaction) {
+	int i;
+	// Free instructions
+	for (i = 0; i < transaction->instructions->length; ++i) {
+		struct sway_transaction_instruction *instruction =
+			transaction->instructions->items[i];
+		if (instruction->container->type == C_VIEW) {
+			struct sway_view *view = instruction->container->sway_view;
+			for (int j = 0; j < view->instructions->length; ++j) {
+				if (view->instructions->items[j] == instruction) {
+					list_del(view->instructions, j);
+					break;
+				}
+			}
+		}
+		free(instruction);
+	}
+	list_free(transaction->instructions);
+
+	// Free damage
+	for (i = 0; i < transaction->damage->length; ++i) {
+		struct wlr_box *box = transaction->damage->items[i];
+		free(box);
+	}
+	list_free(transaction->damage);
+
+	free(transaction);
+}
+
+void transaction_add_container(struct sway_transaction *transaction,
+		struct sway_container *container) {
+	struct sway_transaction_instruction *instruction =
+		calloc(1, sizeof(struct sway_transaction_instruction));
+	instruction->transaction = transaction;
+	instruction->container = container;
+
+	// Copy the container's main (pending) properties into the instruction state
+	struct sway_container_state *state = &instruction->state;
+	state->layout = container->layout;
+	state->swayc_x = container->x;
+	state->swayc_y = container->y;
+	state->swayc_width = container->width;
+	state->swayc_height = container->height;
+	state->has_gaps = container->has_gaps;
+	state->current_gaps = container->current_gaps;
+	state->gaps_inner = container->gaps_inner;
+	state->gaps_outer = container->gaps_outer;
+
+	if (container->type == C_VIEW) {
+		struct sway_view *view = container->sway_view;
+		state->view_x = view->x;
+		state->view_y = view->y;
+		state->view_width = view->width;
+		state->view_height = view->height;
+		state->is_fullscreen = view->is_fullscreen;
+		state->border = view->border;
+		state->border_thickness = view->border_thickness;
+		state->border_top = view->border_top;
+		state->border_left = view->border_left;
+		state->border_right = view->border_right;
+		state->border_bottom = view->border_bottom;
+	}
+
+	list_add(transaction->instructions, instruction);
+}
+
+void transaction_add_damage(struct sway_transaction *transaction,
+		struct wlr_box *_box) {
+	struct wlr_box *box = calloc(1, sizeof(struct wlr_box));
+	memcpy(box, _box, sizeof(struct wlr_box));
+	list_add(transaction->damage, box);
+}
+
+static void save_view_texture(struct sway_view *view) {
+	wlr_texture_destroy(view->saved_texture);
+	view->saved_texture = NULL;
+
+	// TODO: Copy the texture and store it in view->saved_texture.
+}
+
+static void remove_saved_view_texture(struct sway_view *view) {
+	wlr_texture_destroy(view->saved_texture);
+	view->saved_texture = NULL;
+}
+
+/**
+ * Apply a transaction to the "current" state of the tree.
+ *
+ * This is mostly copying stuff from the pending state into the main swayc
+ * properties, but also includes reparenting and deleting containers.
+ */
+static void transaction_apply(struct sway_transaction *transaction) {
+	int i;
+	for (i = 0; i < transaction->instructions->length; ++i) {
+		struct sway_transaction_instruction *instruction =
+			transaction->instructions->items[i];
+		struct sway_container *container = instruction->container;
+
+		memcpy(&instruction->container->current, &instruction->state,
+				sizeof(struct sway_container_state));
+
+		if (container->type == C_VIEW) {
+			remove_saved_view_texture(container->sway_view);
+		}
+	}
+
+	// Damage
+	for (i = 0; i < transaction->damage->length; ++i) {
+		struct wlr_box *box = transaction->damage->items[i];
+		for (int j = 0; j < root_container.children->length; ++j) {
+			struct sway_container *output = root_container.children->items[j];
+			output_damage_box(output->sway_output, box);
+		}
+	}
+
+	update_debug_tree();
+}
+
+static int handle_timeout(void *data) {
+	struct sway_transaction *transaction = data;
+	wlr_log(L_DEBUG, "Transaction %p timed out (%li waiting), applying anyway",
+			transaction, transaction->num_waiting);
+	transaction_apply(transaction);
+	transaction_destroy(transaction);
+	return 0;
+}
+
+void transaction_commit(struct sway_transaction *transaction) {
+	wlr_log(L_DEBUG, "Transaction %p committing with %i instructions",
+			transaction, transaction->instructions->length);
+	transaction->num_waiting = 0;
+	for (int i = 0; i < transaction->instructions->length; ++i) {
+		struct sway_transaction_instruction *instruction =
+			transaction->instructions->items[i];
+		struct sway_container *con = instruction->container;
+		if (con->type == C_VIEW &&
+				(con->current.view_width != instruction->state.view_width ||
+				 con->current.view_height != instruction->state.view_height)) {
+			instruction->serial = view_configure(con->sway_view,
+					instruction->state.view_x,
+					instruction->state.view_y,
+					instruction->state.view_width,
+					instruction->state.view_height);
+			if (instruction->serial) {
+				save_view_texture(con->sway_view);
+				list_add(con->sway_view->instructions, instruction);
+				++transaction->num_waiting;
+			}
+		}
+	}
+	if (!transaction->num_waiting) {
+		// This can happen if the transaction only contains xwayland views
+		wlr_log(L_DEBUG, "Transaction %p has nothing to wait for, applying",
+				transaction);
+		transaction_apply(transaction);
+		transaction_destroy(transaction);
+		return;
+	}
+
+	// Set up a timer which the views must respond within
+	transaction->timer = wl_event_loop_add_timer(server.wl_event_loop,
+			handle_timeout, transaction);
+	wl_event_source_timer_update(transaction->timer, TIMEOUT_MS);
+}
+
+void transaction_notify_view_ready(struct sway_view *view, uint32_t serial) {
+	// Find the instruction
+	struct sway_transaction_instruction *instruction = NULL;
+	for (int i = 0; i < view->instructions->length; ++i) {
+		struct sway_transaction_instruction *tmp_instruction =
+			view->instructions->items[i];
+		if (tmp_instruction->serial == serial) {
+			instruction = tmp_instruction;
+			list_del(view->instructions, i);
+			break;
+		}
+	}
+	if (!instruction) {
+		// This can happen if the view acknowledges the configure after the
+		// transaction has timed out and applied.
+		return;
+	}
+	// If all views are ready, apply the transaction
+	struct sway_transaction *transaction = instruction->transaction;
+	if (--transaction->num_waiting == 0) {
+		wlr_log(L_DEBUG, "Transaction %p is ready, applying", transaction);
+		wl_event_source_timer_update(transaction->timer, 0);
+		transaction_apply(transaction);
+		transaction_destroy(transaction);
+	}
+}