| 1 | module yank_stack_module |
| 2 | use iso_fortran_env, only: int32 |
| 3 | implicit none |
| 4 | private |
| 5 | |
| 6 | public :: yank_stack_t, init_yank_stack, cleanup_yank_stack |
| 7 | public :: push_yank, pop_yank, peek_yank, clear_yank_stack |
| 8 | |
| 9 | integer, parameter :: MAX_YANK_SIZE = 1024 * 1024 ! 1MB max per entry |
| 10 | integer, parameter :: MAX_YANK_ENTRIES = 100 |
| 11 | |
| 12 | type :: yank_entry_t |
| 13 | character(len=:), allocatable :: text |
| 14 | end type yank_entry_t |
| 15 | |
| 16 | type :: yank_stack_t |
| 17 | type(yank_entry_t), allocatable :: entries(:) |
| 18 | integer :: top = 0 |
| 19 | integer :: capacity = MAX_YANK_ENTRIES |
| 20 | end type yank_stack_t |
| 21 | |
| 22 | contains |
| 23 | |
| 24 | subroutine init_yank_stack(stack) |
| 25 | type(yank_stack_t), intent(out) :: stack |
| 26 | |
| 27 | allocate(stack%entries(stack%capacity)) |
| 28 | stack%top = 0 |
| 29 | end subroutine init_yank_stack |
| 30 | |
| 31 | subroutine cleanup_yank_stack(stack) |
| 32 | type(yank_stack_t), intent(inout) :: stack |
| 33 | integer :: i |
| 34 | |
| 35 | if (allocated(stack%entries)) then |
| 36 | do i = 1, stack%top |
| 37 | if (allocated(stack%entries(i)%text)) then |
| 38 | deallocate(stack%entries(i)%text) |
| 39 | end if |
| 40 | end do |
| 41 | deallocate(stack%entries) |
| 42 | end if |
| 43 | stack%top = 0 |
| 44 | end subroutine cleanup_yank_stack |
| 45 | |
| 46 | subroutine push_yank(stack, text) |
| 47 | type(yank_stack_t), intent(inout) :: stack |
| 48 | character(len=*), intent(in) :: text |
| 49 | integer :: i |
| 50 | |
| 51 | ! Check if we need to grow the stack |
| 52 | if (stack%top >= stack%capacity) then |
| 53 | ! Shift entries down, losing the oldest |
| 54 | do i = 1, stack%capacity - 1 |
| 55 | if (allocated(stack%entries(i)%text)) then |
| 56 | deallocate(stack%entries(i)%text) |
| 57 | end if |
| 58 | if (allocated(stack%entries(i+1)%text)) then |
| 59 | allocate(character(len=len(stack%entries(i+1)%text)) :: stack%entries(i)%text) |
| 60 | stack%entries(i)%text = stack%entries(i+1)%text |
| 61 | end if |
| 62 | end do |
| 63 | stack%top = stack%capacity - 1 |
| 64 | end if |
| 65 | |
| 66 | ! Add new entry |
| 67 | stack%top = stack%top + 1 |
| 68 | if (allocated(stack%entries(stack%top)%text)) then |
| 69 | deallocate(stack%entries(stack%top)%text) |
| 70 | end if |
| 71 | |
| 72 | ! Limit text size |
| 73 | if (len(text) > MAX_YANK_SIZE) then |
| 74 | allocate(character(len=MAX_YANK_SIZE) :: stack%entries(stack%top)%text) |
| 75 | stack%entries(stack%top)%text = text(1:MAX_YANK_SIZE) |
| 76 | else |
| 77 | allocate(character(len=len(text)) :: stack%entries(stack%top)%text) |
| 78 | stack%entries(stack%top)%text = text |
| 79 | end if |
| 80 | end subroutine push_yank |
| 81 | |
| 82 | function pop_yank(stack) result(text) |
| 83 | type(yank_stack_t), intent(inout) :: stack |
| 84 | character(len=:), allocatable :: text |
| 85 | |
| 86 | if (stack%top > 0) then |
| 87 | if (allocated(stack%entries(stack%top)%text)) then |
| 88 | allocate(character(len=len(stack%entries(stack%top)%text)) :: text) |
| 89 | text = stack%entries(stack%top)%text |
| 90 | deallocate(stack%entries(stack%top)%text) |
| 91 | else |
| 92 | text = '' |
| 93 | end if |
| 94 | stack%top = stack%top - 1 |
| 95 | else |
| 96 | text = '' |
| 97 | end if |
| 98 | end function pop_yank |
| 99 | |
| 100 | function peek_yank(stack) result(text) |
| 101 | type(yank_stack_t), intent(in) :: stack |
| 102 | character(len=:), allocatable :: text |
| 103 | |
| 104 | if (stack%top > 0) then |
| 105 | if (allocated(stack%entries(stack%top)%text)) then |
| 106 | allocate(character(len=len(stack%entries(stack%top)%text)) :: text) |
| 107 | text = stack%entries(stack%top)%text |
| 108 | else |
| 109 | text = '' |
| 110 | end if |
| 111 | else |
| 112 | text = '' |
| 113 | end if |
| 114 | end function peek_yank |
| 115 | |
| 116 | subroutine clear_yank_stack(stack) |
| 117 | type(yank_stack_t), intent(inout) :: stack |
| 118 | integer :: i |
| 119 | |
| 120 | do i = 1, stack%top |
| 121 | if (allocated(stack%entries(i)%text)) then |
| 122 | deallocate(stack%entries(i)%text) |
| 123 | end if |
| 124 | end do |
| 125 | stack%top = 0 |
| 126 | end subroutine clear_yank_stack |
| 127 | |
| 128 | end module yank_stack_module |