/usr/share/ada/adainclude/opentoken/opentoken-token-linked_list.adb is in libopentoken5-dev 6.0b-4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 | -------------------------------------------------------------------------------
--
-- Copyright (C) 2009 Stephe Leake
-- Copyright (C) 1999, 2000 Ted Dennison
--
-- This file is part of the OpenToken package.
--
-- The OpenToken package is free software; you can redistribute it and/or
-- modify it under the terms of the GNU General Public License as published
-- by the Free Software Foundation; either version 3, or (at your option)
-- any later version. The OpenToken package is distributed in the hope that
-- it will be useful, but WITHOUT ANY WARRANTY; without even the implied
-- warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-- GNU General Public License for more details. You should have received
-- a copy of the GNU General Public License distributed with the OpenToken
-- package; see file GPL.txt. If not, write to the Free Software Foundation,
-- 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
--
-- As a special exception, if other files instantiate generics from
-- this unit, or you link this unit with other files to produce an
-- executable, this unit does not by itself cause the resulting
-- executable to be covered by the GNU General Public License. This
-- exception does not however invalidate any other reasons why the
-- executable file might be covered by the GNU Public License.
--
-------------------------------------------------------------------------------
with Ada.Unchecked_Deallocation;
package body OpenToken.Token.Linked_List is
procedure Free is new Ada.Unchecked_Deallocation (List_Node, List_Node_Ptr);
function Only (Subject : in OpenToken.Token.Handle) return Instance is
New_Node : constant List_Node_Ptr :=
new List_Node'(Token => Subject,
Count => 1,
Next => null
);
begin
return (Ada.Finalization.Controlled with
Head => New_Node,
Tail => New_Node
);
end Only;
function "&" (Left : in OpenToken.Token.Handle;
Right : in OpenToken.Token.Handle) return Instance is
Right_Node : constant List_Node_Ptr :=
new List_Node'(Token => Right,
Count => 1,
Next => null
);
begin
return (Ada.Finalization.Controlled with
Head => new List_Node'(Token => Left,
Count => 1,
Next => Right_Node
),
Tail => Right_Node
);
end "&";
function "&"
(Left : in OpenToken.Token.Handle;
Right : in Instance)
return Instance
is
Left_Node : constant List_Node_Ptr :=
new List_Node'(Token => Left,
Count => 1,
Next => Right.Head
);
Last_Node : List_Node_Ptr := Right.Tail;
begin
Right.Head.Count := Right.Head.Count + 1;
if Last_Node = null then
Last_Node := Left_Node;
end if;
return (Ada.Finalization.Controlled with
Head => Left_Node,
Tail => Last_Node
);
end "&";
function "&" (Left : in Instance;
Right : in OpenToken.Token.Handle) return Instance is
New_Node : constant List_Node_Ptr :=
new List_Node'(Token => Right,
Count => 1,
Next => null
);
First_Node : List_Node_Ptr;
begin
Left.Head.Count := Left.Head.Count + 1;
if Left.Tail = null then
First_Node := New_Node;
else
First_Node := Left.Head;
Left.Tail.Next := New_Node;
end if;
return (Ada.Finalization.Controlled with
Head => First_Node,
Tail => New_Node
);
end "&";
function "&" (Left : in Instance;
Right : in Instance) return Instance is
begin
Left.Tail.Next := Right.Head;
Left.Head.Count := Left.Head.Count + 1;
Right.Head.Count := Right.Head.Count + 1;
return (Ada.Finalization.Controlled with
Head => Left.Head,
Tail => Right.Tail
);
end "&";
procedure Enqueue
(List : in out Instance;
Token : in OpenToken.Token.Handle)
is
New_Node : constant List_Node_Ptr :=
new List_Node'(Token => Token,
Count => 1,
Next => List.Head
);
begin
if List.Tail = null then
List.Tail := New_Node;
end if;
List.Head := New_Node;
end Enqueue;
procedure Clean (List : in out Instance) is
Node : List_Node_Ptr := List.Head;
Next : List_Node_Ptr;
begin
-- Deallocate all the nodes in the list, along with all their tokens
while Node /= null loop
Next := Node.Next;
Free (Node);
Node := Next;
end loop;
List.Head := null;
List.Tail := null;
end Clean;
--------------------------------------------------------------------------
-- A controlled object gets adjusted during an assignment,
-- immediately after making a bit-wise copy from the value on the
-- right hand side to the object on the left hand side.
--
-- When we assign one list object to another, we have to increment
-- the reference count, because there is now one more object
-- referring to that node
--
----------------------------------------------------------------------------
overriding procedure Adjust (List : in out Instance) is
begin
if List.Head /= null then
List.Head.Count := List.Head.Count + 1;
end if;
end Adjust;
--------------------------------------------------------------------------
-- Dereferencing of one node can cause a chain reaction of node
-- dereferences to occur. When the reference count for a node
-- drops to zero, you have to return the node to storage. That
-- means there's one less reference to the next node, so that next
-- node needs to have its reference count decremented. But if its
-- count goes to zero, then you have to dereference its next node,
-- and so on.
--
-- The recursion terminates when you decrement a node whose
-- reference count is greater than one, or you fall off the end of
-- the list (because the reference counts of all the nodes in the
-- list were one).
--
----------------------------------------------------------------------------
procedure Dereference (Node : in out List_Node_Ptr) is
begin
Node.Count := Node.Count - 1;
if Node.Count = 0 then
if Node.Next /= null then
Dereference (Node.Next);
end if;
-- Free the dynamicly allocated memory
Free (Node);
end if;
end Dereference;
--------------------------------------------------------------------------
-- A controlled object gets finalized immediately prior to the
-- bit-wise copy, and when the scope in which the object is
-- declared ends. When a list object is finalized, it means there
-- is one less list object pointing to the first node, so you have
-- to decrement the reference Count.
--
----------------------------------------------------------------------------
overriding procedure Finalize (List : in out Instance) is
begin
if List.Head /= null then
Dereference (List.Head);
if List.Head = null then
List.Tail := null;
end if;
end if;
end Finalize;
function Initial_Iterator (List : in Instance) return List_Iterator is
begin
return List_Iterator (List.Head);
end Initial_Iterator;
procedure Next_Token (Iterator : in out List_Iterator) is
begin
if Iterator /= null then
Iterator := List_Iterator (Iterator.Next);
end if;
end Next_Token;
function Token_Handle (Iterator : in List_Iterator) return OpenToken.Token.Handle is
begin
if Iterator = null then
return null;
end if;
return Iterator.Token;
end Token_Handle;
function Names (List : in List_Iterator) return String
is
Next_Iteration : List_Iterator := List;
This_Name : constant String := Name_Dispatch (Token_Handle (List));
begin
Next_Token (Next_Iteration);
if Next_Iteration = Null_Iterator then
return This_Name;
else
return This_Name & ", " & Names (Next_Iteration);
end if;
end Names;
function Names (List : in Instance) return String
is begin
return Names (Initial_Iterator (List));
end Names;
end OpenToken.Token.Linked_List;
|