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
|
------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- S Y S T E M . H T A B L E --
-- --
-- B o d y --
-- --
-- Copyright (C) 1995-2010, AdaCore --
-- --
-- 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 2, 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. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING. If not, write --
-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
-- Boston, MA 02110-1301, 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. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
pragma Compiler_Unit;
with Ada.Unchecked_Deallocation;
with System.String_Hash;
package body System.HTable is
-------------------
-- Static_HTable --
-------------------
package body Static_HTable is
Table : array (Header_Num) of Elmt_Ptr;
Iterator_Index : Header_Num;
Iterator_Ptr : Elmt_Ptr;
Iterator_Started : Boolean := False;
function Get_Non_Null return Elmt_Ptr;
-- Returns Null_Ptr if Iterator_Started is false or the Table is empty.
-- Returns Iterator_Ptr if non null, or the next non null element in
-- table if any.
---------
-- Get --
---------
function Get (K : Key) return Elmt_Ptr is
Elmt : Elmt_Ptr;
begin
Elmt := Table (Hash (K));
loop
if Elmt = Null_Ptr then
return Null_Ptr;
elsif Equal (Get_Key (Elmt), K) then
return Elmt;
else
Elmt := Next (Elmt);
end if;
end loop;
end Get;
---------------
-- Get_First --
---------------
function Get_First return Elmt_Ptr is
begin
Iterator_Started := True;
Iterator_Index := Table'First;
Iterator_Ptr := Table (Iterator_Index);
return Get_Non_Null;
end Get_First;
--------------
-- Get_Next --
--------------
function Get_Next return Elmt_Ptr is
begin
if not Iterator_Started then
return Null_Ptr;
end if;
Iterator_Ptr := Next (Iterator_Ptr);
return Get_Non_Null;
end Get_Next;
------------------
-- Get_Non_Null --
------------------
function Get_Non_Null return Elmt_Ptr is
begin
while Iterator_Ptr = Null_Ptr loop
if Iterator_Index = Table'Last then
Iterator_Started := False;
return Null_Ptr;
end if;
Iterator_Index := Iterator_Index + 1;
Iterator_Ptr := Table (Iterator_Index);
end loop;
return Iterator_Ptr;
end Get_Non_Null;
------------
-- Remove --
------------
procedure Remove (K : Key) is
Index : constant Header_Num := Hash (K);
Elmt : Elmt_Ptr;
Next_Elmt : Elmt_Ptr;
begin
Elmt := Table (Index);
if Elmt = Null_Ptr then
return;
elsif Equal (Get_Key (Elmt), K) then
Table (Index) := Next (Elmt);
else
loop
Next_Elmt := Next (Elmt);
if Next_Elmt = Null_Ptr then
return;
elsif Equal (Get_Key (Next_Elmt), K) then
Set_Next (Elmt, Next (Next_Elmt));
return;
else
Elmt := Next_Elmt;
end if;
end loop;
end if;
end Remove;
-----------
-- Reset --
-----------
procedure Reset is
begin
for J in Table'Range loop
Table (J) := Null_Ptr;
end loop;
end Reset;
---------
-- Set --
---------
procedure Set (E : Elmt_Ptr) is
Index : Header_Num;
begin
Index := Hash (Get_Key (E));
Set_Next (E, Table (Index));
Table (Index) := E;
end Set;
end Static_HTable;
-------------------
-- Simple_HTable --
-------------------
package body Simple_HTable is
type Element_Wrapper;
type Elmt_Ptr is access all Element_Wrapper;
type Element_Wrapper is record
K : Key;
E : Element;
Next : Elmt_Ptr;
end record;
procedure Free is new
Ada.Unchecked_Deallocation (Element_Wrapper, Elmt_Ptr);
procedure Set_Next (E : Elmt_Ptr; Next : Elmt_Ptr);
function Next (E : Elmt_Ptr) return Elmt_Ptr;
function Get_Key (E : Elmt_Ptr) return Key;
package Tab is new Static_HTable (
Header_Num => Header_Num,
Element => Element_Wrapper,
Elmt_Ptr => Elmt_Ptr,
Null_Ptr => null,
Set_Next => Set_Next,
Next => Next,
Key => Key,
Get_Key => Get_Key,
Hash => Hash,
Equal => Equal);
---------
-- Get --
---------
function Get (K : Key) return Element is
Tmp : constant Elmt_Ptr := Tab.Get (K);
begin
if Tmp = null then
return No_Element;
else
return Tmp.E;
end if;
end Get;
---------------
-- Get_First --
---------------
function Get_First return Element is
Tmp : constant Elmt_Ptr := Tab.Get_First;
begin
if Tmp = null then
return No_Element;
else
return Tmp.E;
end if;
end Get_First;
procedure Get_First (K : in out Key; E : out Element) is
Tmp : constant Elmt_Ptr := Tab.Get_First;
begin
if Tmp = null then
E := No_Element;
else
K := Tmp.K;
E := Tmp.E;
end if;
end Get_First;
-------------
-- Get_Key --
-------------
function Get_Key (E : Elmt_Ptr) return Key is
begin
return E.K;
end Get_Key;
--------------
-- Get_Next --
--------------
function Get_Next return Element is
Tmp : constant Elmt_Ptr := Tab.Get_Next;
begin
if Tmp = null then
return No_Element;
else
return Tmp.E;
end if;
end Get_Next;
procedure Get_Next (K : in out Key; E : out Element) is
Tmp : constant Elmt_Ptr := Tab.Get_Next;
begin
if Tmp = null then
E := No_Element;
else
K := Tmp.K;
E := Tmp.E;
end if;
end Get_Next;
----------
-- Next --
----------
function Next (E : Elmt_Ptr) return Elmt_Ptr is
begin
return E.Next;
end Next;
------------
-- Remove --
------------
procedure Remove (K : Key) is
Tmp : Elmt_Ptr;
begin
Tmp := Tab.Get (K);
if Tmp /= null then
Tab.Remove (K);
Free (Tmp);
end if;
end Remove;
-----------
-- Reset --
-----------
procedure Reset is
E1, E2 : Elmt_Ptr;
begin
E1 := Tab.Get_First;
while E1 /= null loop
E2 := Tab.Get_Next;
Free (E1);
E1 := E2;
end loop;
Tab.Reset;
end Reset;
---------
-- Set --
---------
procedure Set (K : Key; E : Element) is
Tmp : constant Elmt_Ptr := Tab.Get (K);
begin
if Tmp = null then
Tab.Set (new Element_Wrapper'(K, E, null));
else
Tmp.E := E;
end if;
end Set;
--------------
-- Set_Next --
--------------
procedure Set_Next (E : Elmt_Ptr; Next : Elmt_Ptr) is
begin
E.Next := Next;
end Set_Next;
end Simple_HTable;
----------
-- Hash --
----------
function Hash (Key : String) return Header_Num is
type Uns is mod 2 ** 32;
function Hash_Fun is
new System.String_Hash.Hash (Character, String, Uns);
begin
return Header_Num'First +
Header_Num'Base (Hash_Fun (Key) mod Header_Num'Range_Length);
end Hash;
end System.HTable;
|
