*************************************************************************
Copyright (C) Olivetti 1989
All Rights reserved
Use and copy of this software and preparation of derivative works based
upon this software are permitted to any person, provided this same
copyright notice and the following Olivetti warranty disclaimer are
included in any copy of the software or any modification thereof or
derivative work therefrom made by any person.
This software is made available AS IS and Olivetti disclaims all
warranties with respect to this software, whether expressed or implied
under any law, including all implied warranties of merchantibility and
fitness for any purpose. In no event shall Olivetti be liable for any
damages whatsoever resulting from loss of use, data or profits or
otherwise arising out of or in connection with the use or performance
of this software.
*************************************************************************
Copyright (C) 1993, Digital Equipment Corporation
All rights reserved.
See the file COPYRIGHT for a full description.
UNSAFE MODULE M3LFingerPrint;
IMPORT Text, TextExtras, ASCII;
IMPORT M3LTypeToText, FingerPrint;
TYPE
Handle = RECORD
texts: REF ARRAY OF TEXT;
components: REF ARRAY OF INTEGER;
count: CARDINAL;
END;
PROCEDURE Incremental(
VAR handle: Handle;
text: Text.T;
VAR f: T)
RAISES {}=
VAR
prev: CARDINAL;
length := Text.Length(text);
pos: CARDINAL := 0;
BEGIN
REPEAT
prev := pos;
WITH endOfText =
NOT TextExtras.FindCharSet(text,
LOOPHOLE(M3LTypeToText.TypeIndexChars, ASCII.Set), pos) DO
WITH sectionLength = pos - prev DO
IF sectionLength # 0 THEN
FingerPrint.TextSubIncremental(
text, prev, sectionLength, f.f1, f.f2);
INC(handle.count, sectionLength);
END;
END;
IF endOfText THEN EXIT END;
END;
VAR
limit: CARDINAL;
index: CARDINAL := 0;
BEGIN
CASE Text.GetChar (text, pos) OF <*NOWARN*>
| M3LTypeToText.TypeIndexOneCh => limit := pos + 1;
| M3LTypeToText.TypeIndexTwoCh => limit := pos + 2;
| M3LTypeToText.TypeIndexThreeCh => limit := pos + 3;
| M3LTypeToText.TypeIndexManyCh => limit := LAST(CARDINAL);
END;
LOOP
INC(pos);
IF pos > limit THEN EXIT END;
WITH ch = Text.GetChar(text, pos) DO
IF ch = M3LTypeToText.TypeIndexManyCh THEN INC(pos); EXIT END;
index := index * M3LTypeToText.TypeIndexBase +
(ORD(Text.GetChar(text, pos)) - ORD(M3LTypeToText.TypeIndexFirstDigitCh));
END;
END;
WITH component = handle.components[index] DO
IF component = -1 THEN
component := index (* was "handle.count" *);
Incremental(handle, handle.texts[index], f);
ELSE
FingerPrint.Incremental(
ORD(M3LTypeToText.TypeIndexOneCh), f.f1, f.f2);
FingerPrint.DataIncremental(
ADR(component), BYTESIZE(component), f.f1, f.f2);
END;
END;
END;
UNTIL pos >= length;
END Incremental;
PROCEDURE Generate(texts: REF ARRAY OF TEXT): REF ARRAY OF T RAISES {}=
VAR
handle: Handle;
res := NEW(REF ARRAY OF T, NUMBER(texts^));
BEGIN
handle.texts := texts;
handle.components := NEW(REF ARRAY OF INTEGER, NUMBER(texts^));
FOR i := 0 TO LAST(texts^) DO
handle.count := 0;
FOR i := 0 TO LAST(handle.components^) DO
handle.components[i] := -1;
END;
Incremental(handle, texts[i], res[i]);
END; (* for *)
RETURN res;
END Generate;
BEGIN
END M3LFingerPrint.