1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME COMPONENTS --
5 -- A D A . S T R I N G S . S E A R C H --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
30 ------------------------------------------------------------------------------
32 -- Note: This code is derived from the ADAR.CSH public domain Ada 83
33 -- versions of the Appendix C string handling packages (code extracted
34 -- from Ada.Strings.Fixed). A significant change is that we optimize the
35 -- case of identity mappings for Count and Index, and also Index_Non_Blank
36 -- is specialized (rather than using the general Index routine).
38 with Ada.Strings.Maps; use Ada.Strings.Maps;
39 with System; use System;
41 package body Ada.Strings.Search is
43 -----------------------
44 -- Local Subprograms --
45 -----------------------
49 Set : Maps.Character_Set;
50 Test : Membership) return Boolean;
51 pragma Inline (Belongs);
52 -- Determines if the given element is in (Test = Inside) or not in
53 -- (Test = Outside) the given character set.
61 Set : Maps.Character_Set;
62 Test : Membership) return Boolean
66 return Is_In (Element, Set);
68 return not Is_In (Element, Set);
79 Mapping : Maps.Character_Mapping := Maps.Identity) return Natural
81 PL1 : constant Integer := Pattern'Length - 1;
96 if Mapping'Address = Maps.Identity'Address then
97 while Ind <= Source'Last - PL1 loop
98 if Pattern = Source (Ind .. Ind + PL1) then
100 Ind := Ind + Pattern'Length;
109 while Ind <= Source'Last - PL1 loop
111 for K in Pattern'Range loop
112 if Pattern (K) /= Value (Mapping, Source (Cur)) then
121 Ind := Ind + Pattern'Length;
136 Mapping : Maps.Character_Mapping_Function) return Natural
138 PL1 : constant Integer := Pattern'Length - 1;
148 -- Check for null pointer in case checks are off
150 if Mapping = null then
151 raise Constraint_Error;
156 while Ind <= Source'Last - PL1 loop
158 for K in Pattern'Range loop
159 if Pattern (K) /= Mapping (Source (Cur)) then
168 Ind := Ind + Pattern'Length;
179 Set : Maps.Character_Set) return Natural
184 for J in Source'Range loop
185 if Is_In (Source (J), Set) then
199 Set : Maps.Character_Set;
201 First : out Positive;
205 for J in Source'Range loop
206 if Belongs (Source (J), Set, Test) then
209 for K in J + 1 .. Source'Last loop
210 if not Belongs (Source (K), Set, Test) then
216 -- Here if J indexes first char of token, and all chars after J
224 -- Here if no token found
226 First := Source'First;
237 Going : Direction := Forward;
238 Mapping : Maps.Character_Mapping := Maps.Identity) return Natural
240 PL1 : constant Integer := Pattern'Length - 1;
244 -- Index for start of match check. This can be negative if the pattern
245 -- length is greater than the string length, which is why this variable
246 -- is Integer instead of Natural. In this case, the search loops do not
247 -- execute at all, so this Ind value is never used.
256 if Going = Forward then
259 -- Unmapped forward case
261 if Mapping'Address = Maps.Identity'Address then
262 for J in 1 .. Source'Length - PL1 loop
263 if Pattern = Source (Ind .. Ind + PL1) then
270 -- Mapped forward case
273 for J in 1 .. Source'Length - PL1 loop
276 for K in Pattern'Range loop
277 if Pattern (K) /= Value (Mapping, Source (Cur)) then
294 -- Unmapped backward case
296 Ind := Source'Last - PL1;
298 if Mapping'Address = Maps.Identity'Address then
299 for J in reverse 1 .. Source'Length - PL1 loop
300 if Pattern = Source (Ind .. Ind + PL1) then
307 -- Mapped backward case
310 for J in reverse 1 .. Source'Length - PL1 loop
313 for K in Pattern'Range loop
314 if Pattern (K) /= Value (Mapping, Source (Cur)) then
329 -- Fall through if no match found. Note that the loops are skipped
330 -- completely in the case of the pattern being longer than the source.
338 Going : Direction := Forward;
339 Mapping : Maps.Character_Mapping_Function) return Natural
341 PL1 : constant Integer := Pattern'Length - 1;
350 -- Check for null pointer in case checks are off
352 if Mapping = null then
353 raise Constraint_Error;
356 -- If Pattern longer than Source it can't be found
358 if Pattern'Length > Source'Length then
364 if Going = Forward then
366 for J in 1 .. Source'Length - PL1 loop
369 for K in Pattern'Range loop
370 if Pattern (K) /= Mapping.all (Source (Cur)) then
386 Ind := Source'Last - PL1;
387 for J in reverse 1 .. Source'Length - PL1 loop
390 for K in Pattern'Range loop
391 if Pattern (K) /= Mapping.all (Source (Cur)) then
405 -- Fall through if no match found. Note that the loops are skipped
406 -- completely in the case of the pattern being longer than the source.
413 Set : Maps.Character_Set;
414 Test : Membership := Inside;
415 Going : Direction := Forward) return Natural
420 if Going = Forward then
421 for J in Source'Range loop
422 if Belongs (Source (J), Set, Test) then
430 for J in reverse Source'Range loop
431 if Belongs (Source (J), Set, Test) then
437 -- Fall through if no match
446 Going : Direction := Forward;
447 Mapping : Maps.Character_Mapping := Maps.Identity) return Natural
450 if Going = Forward then
451 if From < Source'First then
456 Index (Source (From .. Source'Last), Pattern, Forward, Mapping);
459 if From > Source'Last then
464 Index (Source (Source'First .. From), Pattern, Backward, Mapping);
472 Going : Direction := Forward;
473 Mapping : Maps.Character_Mapping_Function) return Natural
476 if Going = Forward then
477 if From < Source'First then
482 (Source (From .. Source'Last), Pattern, Forward, Mapping);
485 if From > Source'Last then
490 (Source (Source'First .. From), Pattern, Backward, Mapping);
496 Set : Maps.Character_Set;
498 Test : Membership := Inside;
499 Going : Direction := Forward) return Natural
502 if Going = Forward then
503 if From < Source'First then
508 Index (Source (From .. Source'Last), Set, Test, Forward);
511 if From > Source'Last then
516 Index (Source (Source'First .. From), Set, Test, Backward);
520 ---------------------
521 -- Index_Non_Blank --
522 ---------------------
524 function Index_Non_Blank
526 Going : Direction := Forward) return Natural
529 if Going = Forward then
530 for J in Source'Range loop
531 if Source (J) /= ' ' then
536 else -- Going = Backward
537 for J in reverse Source'Range loop
538 if Source (J) /= ' ' then
544 -- Fall through if no match
549 function Index_Non_Blank
552 Going : Direction := Forward) return Natural
555 if Going = Forward then
556 if From < Source'First then
561 Index_Non_Blank (Source (From .. Source'Last), Forward);
564 if From > Source'Last then
569 Index_Non_Blank (Source (Source'First .. From), Backward);
573 end Ada.Strings.Search;