This file is indexed.

/usr/share/ada/adainclude/gnatvsn/table.adb is in libgnatvsn7-dev 7.3.0-16ubuntu3.

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
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                                T A B L E                                 --
--                                                                          --
--                                 B o d y                                  --
--                                                                          --
--          Copyright (C) 1992-2016, Free Software Foundation, Inc.         --
--                                                                          --
-- GNAT is free software;  you can  redistribute it  and/or modify it under --
-- terms of the  GNU General Public License as published  by the Free Soft- --
-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
--                                                                          --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception,   --
-- version 3.1, as published by the Free Software Foundation.               --
--                                                                          --
-- You should have received a copy of the GNU General Public License and    --
-- a copy of the GCC Runtime Library Exception along with this program;     --
-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
-- <http://www.gnu.org/licenses/>.                                          --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
--                                                                          --
------------------------------------------------------------------------------

with Debug;   use Debug;
with Opt;     use Opt;
with Output;  use Output;
with System;  use System;
with Tree_IO; use Tree_IO;

with System.Memory; use System.Memory;

with Unchecked_Conversion;

pragma Elaborate_All (Output);

package body Table is
   package body Table is

      Min : constant Int := Int (Table_Low_Bound);
      --  Subscript of the minimum entry in the currently allocated table

      Length : Int := 0;
      --  Number of entries in currently allocated table. The value of zero
      --  ensures that we initially allocate the table.

      -----------------------
      -- Local Subprograms --
      -----------------------

      procedure Reallocate;
      --  Reallocate the existing table according to the current value stored
      --  in Max. Works correctly to do an initial allocation if the table
      --  is currently null.

      function Tree_Get_Table_Address return Address;
      --  Return Null_Address if the table length is zero,
      --  Table (First)'Address if not.

      pragma Warnings (Off);
      --  Turn off warnings. The following unchecked conversions are only used
      --  internally in this package, and cannot never result in any instances
      --  of improperly aliased pointers for the client of the package.

      function To_Address is new Unchecked_Conversion (Table_Ptr, Address);
      function To_Pointer is new Unchecked_Conversion (Address, Table_Ptr);

      pragma Warnings (On);

      ------------
      -- Append --
      ------------

      procedure Append (New_Val : Table_Component_Type) is
      begin
         Set_Item (Table_Index_Type (Last_Val + 1), New_Val);
      end Append;

      ----------------
      -- Append_All --
      ----------------

      procedure Append_All (New_Vals : Table_Type) is
      begin
         for J in New_Vals'Range loop
            Append (New_Vals (J));
         end loop;
      end Append_All;

      --------------------
      -- Decrement_Last --
      --------------------

      procedure Decrement_Last is
      begin
         Last_Val := Last_Val - 1;
      end Decrement_Last;

      ----------
      -- Free --
      ----------

      procedure Free is
      begin
         Free (To_Address (Table));
         Table := null;
         Length := 0;
      end Free;

      --------------------
      -- Increment_Last --
      --------------------

      procedure Increment_Last is
      begin
         Last_Val := Last_Val + 1;

         if Last_Val > Max then
            Reallocate;
         end if;
      end Increment_Last;

      ----------
      -- Init --
      ----------

      procedure Init is
         Old_Length : constant Int := Length;

      begin
         Locked   := False;
         Last_Val := Min - 1;
         Max      := Min + (Table_Initial * Table_Factor) - 1;
         Length   := Max - Min + 1;

         --  If table is same size as before (happens when table is never
         --  expanded which is a common case), then simply reuse it. Note
         --  that this also means that an explicit Init call right after
         --  the implicit one in the package body is harmless.

         if Old_Length = Length then
            return;

         --  Otherwise we can use Reallocate to get a table of the right size.
         --  Note that Reallocate works fine to allocate a table of the right
         --  initial size when it is first allocated.

         else
            Reallocate;
         end if;
      end Init;

      ----------
      -- Last --
      ----------

      function Last return Table_Index_Type is
      begin
         return Table_Index_Type (Last_Val);
      end Last;

      ----------------
      -- Reallocate --
      ----------------

      procedure Reallocate is
         New_Size   : Memory.size_t;
         New_Length : Long_Long_Integer;

      begin
         if Max < Last_Val then
            pragma Assert (not Locked);

            --  Make sure that we have at least the initial allocation. This
            --  is needed in cases where a zero length table is written out.

            Length := Int'Max (Length, Table_Initial);

            --  Now increment table length until it is sufficiently large. Use
            --  the increment value or 10, which ever is larger (the reason
            --  for the use of 10 here is to ensure that the table does really
            --  increase in size (which would not be the case for a table of
            --  length 10 increased by 3% for instance). Do the intermediate
            --  calculation in Long_Long_Integer to avoid overflow.

            while Max < Last_Val loop
               New_Length :=
                 Long_Long_Integer (Length) *
                    (100 + Long_Long_Integer (Table_Increment)) / 100;
               Length := Int'Max (Int (New_Length), Length + 10);
               Max := Min + Length - 1;
            end loop;

            if Debug_Flag_D then
               Write_Str ("--> Allocating new ");
               Write_Str (Table_Name);
               Write_Str (" table, size = ");
               Write_Int (Max - Min + 1);
               Write_Eol;
            end if;
         end if;

         --  Do the intermediate calculation in size_t to avoid signed overflow

         New_Size :=
           Memory.size_t (Max - Min + 1) *
                                    (Table_Type'Component_Size / Storage_Unit);

         if Table = null then
            Table := To_Pointer (Alloc (New_Size));

         elsif New_Size > 0 then
            Table :=
              To_Pointer (Realloc (Ptr  => To_Address (Table),
                                   Size => New_Size));
         end if;

         if Length /= 0 and then Table = null then
            Set_Standard_Error;
            Write_Str ("available memory exhausted");
            Write_Eol;
            Set_Standard_Output;
            raise Unrecoverable_Error;
         end if;
      end Reallocate;

      -------------
      -- Release --
      -------------

      procedure Release is
         Extra_Length : Int;
         Size         : Memory.size_t;

      begin
         Length := Last_Val - Int (Table_Low_Bound) + 1;
         Size   := Memory.size_t (Length) *
                     (Table_Type'Component_Size / Storage_Unit);

         --  If the size of the table exceeds the release threshold then leave
         --  space to store as many extra elements as 0.1% of the table length.

         if Release_Threshold > 0
           and then Size > Memory.size_t (Release_Threshold)
         then
            Extra_Length := Length / 1000;
            Length := Length + Extra_Length;
            Max    := Int (Table_Low_Bound) + Length - 1;

            if Debug_Flag_D then
               Write_Str ("--> Release_Threshold reached (length=");
               Write_Int (Int (Size));
               Write_Str ("): leaving room space for ");
               Write_Int (Extra_Length);
               Write_Str (" components");
               Write_Eol;
            end if;
         else
            Max := Last_Val;
         end if;

         Reallocate;
      end Release;

      -------------
      -- Restore --
      -------------

      procedure Restore (T : Saved_Table) is
      begin
         Free (To_Address (Table));
         Last_Val := T.Last_Val;
         Max      := T.Max;
         Table    := T.Table;
         Length   := Max - Min + 1;
      end Restore;

      ----------
      -- Save --
      ----------

      function Save return Saved_Table is
         Res : Saved_Table;

      begin
         Res.Last_Val := Last_Val;
         Res.Max      := Max;
         Res.Table    := Table;

         Table  := null;
         Length := 0;
         Init;
         return Res;
      end Save;

      --------------
      -- Set_Item --
      --------------

      procedure Set_Item
         (Index : Table_Index_Type;
          Item  : Table_Component_Type)
      is
         --  If Item is a value within the current allocation, and we are going
         --  to reallocate, then we must preserve an intermediate copy here
         --  before calling Increment_Last. Otherwise, if Table_Component_Type
         --  is passed by reference, we are going to end up copying from
         --  storage that might have been deallocated from Increment_Last
         --  calling Reallocate.

         subtype Allocated_Table_T is
           Table_Type (Table'First .. Table_Index_Type (Max + 1));
         --  A constrained table subtype one element larger than the currently
         --  allocated table.

         Allocated_Table_Address : constant System.Address :=
                                     Table.all'Address;
         --  Used for address clause below (we can't use non-static expression
         --  Table.all'Address directly in the clause because some older
         --  versions of the compiler do not allow it).

         Allocated_Table : Allocated_Table_T;
         pragma Import (Ada, Allocated_Table);
         pragma Suppress (Range_Check, On => Allocated_Table);
         for Allocated_Table'Address use Allocated_Table_Address;
         --  Allocated_Table represents the currently allocated array, plus one
         --  element (the supplementary element is used to have a convenient
         --  way of computing the address just past the end of the current
         --  allocation). Range checks are suppressed because this unit
         --  uses direct calls to System.Memory for allocation, and this can
         --  yield misaligned storage (and we cannot rely on the bootstrap
         --  compiler supporting specifically disabling alignment checks, so we
         --  need to suppress all range checks). It is safe to suppress this
         --  check here because we know that a (possibly misaligned) object
         --  of that type does actually exist at that address.
         --  ??? We should really improve the allocation circuitry here to
         --  guarantee proper alignment.

         Need_Realloc : constant Boolean := Int (Index) > Max;
         --  True if this operation requires storage reallocation (which may
         --  involve moving table contents around).

      begin
         --  If we're going to reallocate, check whether Item references an
         --  element of the currently allocated table.

         if Need_Realloc
           and then Allocated_Table'Address <= Item'Address
           and then Item'Address <
                      Allocated_Table (Table_Index_Type (Max + 1))'Address
         then
            --  If so, save a copy on the stack because Increment_Last will
            --  reallocate storage and might deallocate the current table.

            declare
               Item_Copy : constant Table_Component_Type := Item;
            begin
               Set_Last (Index);
               Table (Index) := Item_Copy;
            end;

         else
            --  Here we know that either we won't reallocate (case of Index <
            --  Max) or that Item is not in the currently allocated table.

            if Int (Index) > Last_Val then
               Set_Last (Index);
            end if;

            Table (Index) := Item;
         end if;
      end Set_Item;

      --------------
      -- Set_Last --
      --------------

      procedure Set_Last (New_Val : Table_Index_Type) is
      begin
         if Int (New_Val) < Last_Val then
            Last_Val := Int (New_Val);

         else
            Last_Val := Int (New_Val);

            if Last_Val > Max then
               Reallocate;
            end if;
         end if;
      end Set_Last;

      ----------------------------
      -- Tree_Get_Table_Address --
      ----------------------------

      function Tree_Get_Table_Address return Address is
      begin
         if Length = 0 then
            return Null_Address;
         else
            return Table (First)'Address;
         end if;
      end Tree_Get_Table_Address;

      ---------------
      -- Tree_Read --
      ---------------

      --  Note: we allocate only the space required to accommodate the data
      --  actually written, which means that a Tree_Write/Tree_Read sequence
      --  does an implicit Release.

      procedure Tree_Read is
      begin
         Tree_Read_Int (Max);
         Last_Val := Max;
         Length := Max - Min + 1;
         Reallocate;

         Tree_Read_Data
           (Tree_Get_Table_Address,
             (Last_Val - Int (First) + 1) *

               --  Note the importance of parenthesizing the following division
               --  to avoid the possibility of intermediate overflow.

               (Table_Type'Component_Size / Storage_Unit));
      end Tree_Read;

      ----------------
      -- Tree_Write --
      ----------------

      --  Note: we write out only the currently valid data, not the entire
      --  contents of the allocated array. See note above on Tree_Read.

      procedure Tree_Write is
      begin
         Tree_Write_Int (Int (Last));
         Tree_Write_Data
           (Tree_Get_Table_Address,
            (Last_Val - Int (First) + 1) *
              (Table_Type'Component_Size / Storage_Unit));
      end Tree_Write;

   begin
      Init;
   end Table;
end Table;