5 files changed, 42 insertions, 22 deletions

diff --git a/common/list.c b/common/list.c
index 39cc10e1..cab10c1e 100644
--- a/common/list.c
+++ b/common/list.c
@@ -62,6 +62,13 @@ void list_cat(list_t *list, list_t *source) {
         }
 }
 
+void list_empty(list_t *list) {
+        list->capacity = 10;
+        list->length = 0;
+        free(list->items);
+        list->items = malloc(sizeof(void*) * list->capacity);
+}
+
 void list_qsort(list_t *list, int compare(const void *left, const void *right)) {
         qsort(list->items, list->length, sizeof(void *), compare);
 }
diff --git a/include/list.h b/include/list.h
index 7eead4ac..d352dbd5 100644
--- a/include/list.h
+++ b/include/list.h
@@ -14,6 +14,7 @@ void list_add(list_t *list, void *item);
 void list_insert(list_t *list, int index, void *item);
 void list_del(list_t *list, int index);
 void list_cat(list_t *list, list_t *source);
+void list_empty(list_t *list);
 // See qsort. Remember to use *_qsort functions as compare functions,
 // because they dereference the left and right arguments first!
 void list_qsort(list_t *list, int compare(const void *left, const void *right));
diff --git a/include/sway/server.h b/include/sway/server.h
index bd96b085..0efc6baa 100644
--- a/include/sway/server.h
+++ b/include/sway/server.h
@@ -47,7 +47,7 @@ struct sway_server {
 
         bool debug_txn_timings;
 
-        struct sway_transaction *head_transaction; // singly linked list
+        list_t *transactions;
 
         // When a view is being destroyed and is waiting for a transaction to
         // complete it will be stored here.
diff --git a/sway/desktop/transaction.c b/sway/desktop/transaction.c
index c29b6661..7a2e78e5 100644
--- a/sway/desktop/transaction.c
+++ b/sway/desktop/transaction.c
@@ -32,7 +32,6 @@ struct sway_transaction {
         list_t *instructions;   // struct sway_transaction_instruction *
         size_t num_waiting;
         size_t num_configures;
-        struct sway_transaction *next;
         struct timespec create_time;
         struct timespec commit_time;
 };
@@ -225,16 +224,24 @@ static void transaction_apply(struct sway_transaction *transaction) {
         }
 }
 
+/**
+ * For simplicity, we only progress the queue if it can be completely flushed.
+ */
 static void transaction_progress_queue() {
-        struct sway_transaction *transaction = server.head_transaction;
-        struct sway_transaction *next = NULL;
-        while (transaction && !transaction->num_waiting) {
-                next = transaction->next;
+        // We iterate this list in reverse because we're more likely to find a
+        // waiting transactions at the end of the list.
+        for (int i = server.transactions->length - 1; i >= 0; --i) {
+                struct sway_transaction *transaction = server.transactions->items[i];
+                if (transaction->num_waiting) {
+                        return;
+                }
+        }
+        for (int i = 0; i < server.transactions->length; ++i) {
+                struct sway_transaction *transaction = server.transactions->items[i];
                 transaction_apply(transaction);
                 transaction_destroy(transaction);
-                transaction = next;
         }
-        server.head_transaction = transaction;
+        list_empty(server.transactions);
 }
 
 static int handle_timeout(void *data) {
@@ -295,18 +302,8 @@ void transaction_commit(struct sway_transaction *transaction) {
         if (server.debug_txn_timings) {
                 clock_gettime(CLOCK_MONOTONIC, &transaction->commit_time);
         }
-        if (server.head_transaction) {
-                // There is another transaction in progress - we must add this one to
-                // the queue so we complete after it.
-                struct sway_transaction *tail = server.head_transaction;
-                while (tail->next) {
-                        tail = tail->next;
-                }
-                tail->next = transaction;
-        } else if (transaction->num_waiting) {
-                // There are no other transactions, but we're not applying immediately
-                // so we must jump in the queue so others will queue behind us.
-                server.head_transaction = transaction;
+        if (server.transactions->length || transaction->num_waiting) {
+                list_add(server.transactions, transaction);
         } else {
                 // There are no other transactions in progress, and this one has nothing
                 // to wait for, so we can skip the queue.
@@ -359,12 +356,24 @@ static void set_instruction_ready(
         }
 }
 
+/**
+ * Mark all of the view's instructions as ready up to and including the
+ * instruction at the given index. This allows the view to skip a configure.
+ */
+static void set_instructions_ready(struct sway_view *view, int index) {
+        for (int i = 0; i <= index; ++i) {
+                struct sway_transaction_instruction *instruction =
+                        view->swayc->instructions->items[i];
+                set_instruction_ready(instruction);
+        }
+}
+
 void transaction_notify_view_ready(struct sway_view *view, uint32_t serial) {
         for (int i = 0; i < view->swayc->instructions->length; ++i) {
                 struct sway_transaction_instruction *instruction =
                         view->swayc->instructions->items[i];
                 if (instruction->serial == serial && !instruction->ready) {
-                        set_instruction_ready(instruction);
+                        set_instructions_ready(view, i);
                         return;
                 }
         }
@@ -377,7 +386,7 @@ void transaction_notify_view_ready_by_size(struct sway_view *view,
                         view->swayc->instructions->items[i];
                 if (!instruction->ready && instruction->state.view_width == width &&
                                 instruction->state.view_height == height) {
-                        set_instruction_ready(instruction);
+                        set_instructions_ready(view, i);
                         return;
                 }
         }
diff --git a/sway/server.c b/sway/server.c
index a2bc5702..884d971e 100644
--- a/sway/server.c
+++ b/sway/server.c
@@ -119,6 +119,8 @@ bool server_init(struct sway_server *server) {
         }
         server->destroying_containers = create_list();
 
+        server->transactions = create_list();
+
         input_manager = input_manager_create(server);
         return true;
 }
@@ -127,6 +129,7 @@ void server_fini(struct sway_server *server) {
         // TODO: free sway-specific resources
         wl_display_destroy(server->wl_display);
         list_free(server->destroying_containers);
+        list_free(server->transactions);
 }
 
 void server_run(struct sway_server *server) {