PriorityQueue

Author: Matter Labs

The library provides the API to interact with the priority queue container

Order of processing operations from queue - FIFO (Fist in - first out)

Note: security-contact: security@matterlabs.dev

Functions

Returns zero if and only if no operations were processed from the queue

function getFirstUnprocessedPriorityTx(Queue storage _queue)
  internal
  view
  returns (uint256);

Returns

Name	Type	Description
`<none>`	`uint256`	Index of the oldest priority operation that wasn't processed yet

function getTotalPriorityTxs(Queue storage _queue)
  internal
  view
  returns (uint256);

Returns

Name	Type	Description
`<none>`	`uint256`	The total number of priority operations that were added to the priority queue, including all processed ones

function getSize(Queue storage _queue) internal view returns (uint256);

Returns

Name	Type	Description
`<none>`	`uint256`	The total number of unprocessed priority operations in a priority queue

function isEmpty(Queue storage _queue) internal view returns (bool);

Returns

Name	Type	Description
`<none>`	`bool`	Whether the priority queue contains no operations

Add the priority operation to the end of the priority queue

function pushBack(Queue storage _queue, PriorityOperation memory _operation)
  internal;

function front(Queue storage _queue)
  internal
  view
  returns (PriorityOperation memory);

Returns

Name	Type	Description
`<none>`	`PriorityOperation`	The first unprocessed priority operation from the queue

Remove the first unprocessed priority operation from the queue

function popFront(Queue storage _queue)
  internal
  returns (PriorityOperation memory priorityOperation);

Returns

Name	Type	Description
`priorityOperation`	`PriorityOperation`	that was popped from the priority queue

Container that stores priority operations

struct Queue {
  mapping(uint256 priorityOpId => PriorityOperation priorityOp) data;
  uint256 tail;
  uint256 head;
}

Properties

Name	Type	Description
`data`	`mapping(uint256 priorityOpId => PriorityOperation priorityOp)`	The inner mapping that saves priority operation by its index
`tail`	`uint256`	The pointer to the free slot
`head`	`uint256`	The pointer to the first unprocessed priority operation, equal to the tail if the queue is empty