<> <> <> <> <> <> <> <> DIRECTORY Basics, RopeReader, RopeFrom, Rope, RopePrivate; RopeReaderMiscImpl: CEDAR MONITOR IMPORTS Basics, RopeReader, Rope, RopePrivate, RopeFrom EXPORTS RopeReader SHARES RopeReader, Rope = BEGIN OPEN RopeReader, RopePrivate; EqSubstrs: PUBLIC PROC [r1,r2: ROPE, start1,start2,len: Offset, rdr1,rdr2: Ref _ NIL] RETURNS [eq: BOOLEAN] = { <<-- uses readers rdr1 and rdr2 to read ropes r1 and r2 to test for equality>> <<-- returns TRUE if r1 is same as len chars of r2 starting at start>> free1, free2: BOOLEAN _ FALSE; size1: Offset _ Rope.InlineSize[r1]; size2: Offset _ Rope.InlineSize[r2]; start1 _ MIN[start1,size1]; start2 _ MIN[start2,size2]; IF len=MaxLen THEN { IF (len _ size1-start1) # size2-start2 THEN RETURN [FALSE] } ELSE IF start1+len > size1 THEN RETURN [FALSE] ELSE IF start2+len > size2 THEN RETURN [FALSE]; IF rdr1 = NIL THEN { rdr1 _ GetRopeReader[]; free1 _ TRUE }; IF rdr2 = NIL THEN { rdr2 _ GetRopeReader[]; free2 _ TRUE }; SetPosition[rdr1,r1,start1]; SetPosition[rdr2,r2,start2]; eq _ TRUE; WHILE len > 0 DO num: NAT _ Short[MIN[len,LAST[NAT]]]; -- loop on NAT instead of Offset len _ len-num; THROUGH [0..num) DO IF Get[rdr1]#Get[rdr2] THEN { eq _ FALSE; GOTO Finis }; ENDLOOP; REPEAT Finis => NULL; ENDLOOP; IF free1 THEN FreeRopeReader[rdr1]; IF free2 THEN FreeRopeReader[rdr2]; }; CompareSubstrs: PUBLIC PROC [ r1, r2: ROPE, start1, len1, start2, len2: Offset, rdr1, rdr2: Ref _ NIL, case: BOOLEAN _ TRUE] RETURNS [result: Basics.Comparison] = { <<-- uses readers rdr1 and rdr2 to compare ropes r1 and r2>> <<-- if ~case then all characters forced lowercase for comparison>> size1: Offset _ Rope.InlineSize[r1]; size2: Offset _ Rope.InlineSize[r2]; rem, rem1, rem2: Offset; free1, free2: BOOLEAN _ FALSE; rem1 _ IF start1 > size1 THEN 0 ELSE size1-start1; rem2 _ IF start2 > size2 THEN 0 ELSE size2-start2; IF rdr1 = NIL THEN { rdr1 _ GetRopeReader[]; free1 _ TRUE }; IF rdr2 = NIL THEN { rdr2 _ GetRopeReader[]; free2 _ TRUE }; len1 _ MIN[len1,rem1]; len2 _ MIN[len2,rem2]; rem _ MIN[len1,len2]; SetPosition[rdr1,r1,start1]; SetPosition[rdr2,r2,start2]; result _ equal; WHILE rem > 0 DO num: NAT _ Short[MIN[rem,LAST[NAT]]]; rem _ rem-num; THROUGH [0..num) DO c1: CHARACTER _ Get[rdr1]; c2: CHARACTER _ Get[rdr2]; IF ~case THEN { <> IF LOOPHOLE[c1-'A, CARDINAL] <= ('Z-'A) THEN c1 _ LOOPHOLE[LOOPHOLE[c1, CARDINAL] + ('a-'A), CHAR]; IF LOOPHOLE[c2-'A, CARDINAL] <= ('Z-'A) THEN c2 _ LOOPHOLE[LOOPHOLE[c2, CARDINAL] + ('a-'A), CHAR]; }; IF c1 # c2 THEN { result _ Basics.CompareCard[LOOPHOLE[c1, CARDINAL], LOOPHOLE[c2, CARDINAL]]; GO TO Finis; }; ENDLOOP; REPEAT Finis => NULL; ENDLOOP; IF free1 THEN FreeRopeReader[rdr1]; IF free2 THEN FreeRopeReader[rdr2]; IF result # equal THEN RETURN; -- if a character differerence, then return it RETURN [Basics.CompareINT[len1, len2]]; -- if equal so far, the length determines }; <<-- implementation of ropes using character arrays>> numCharsArrays: INT _ 0; -- number allocated spacesFinalized: INT _ 0; charsFinalized: INT _ 0; CharsRope: PUBLIC SAFE PROC [chars: Chars] RETURNS [ROPE] = TRUSTED { RETURN [Rope.MakeRope[LOOPHOLE[chars], charsPerArray, CharsFetch, CharsMap]]; }; CharsFetch: SAFE PROC [data: REF, index: Offset] RETURNS [c:CHAR] = TRUSTED { WITH data SELECT FROM x: Chars => RETURN[x[Short[index]]]; ENDCASE => ERROR Rope.NoRope }; CharsMap: SAFE PROC [base: REF, start,len: Offset, action: PROC [CHAR] RETURNS [BOOLEAN]] RETURNS [BOOLEAN] = TRUSTED { WITH base SELECT FROM x: Chars => { st: NAT _ Short[start]; FOR i: NAT IN [st..st+Short[len]) DO IF action[x[i]] THEN RETURN [TRUE]; ENDLOOP }; ENDCASE => ERROR Rope.NoRope; RETURN [FALSE] }; <<-- ***** rope reader cache>> Create: PUBLIC PROC RETURNS [Ref] = { RETURN[RopeFrom.qZone.NEW[Body]] }; roperdr1, roperdr2, roperdr3: Ref; -- shared rope readers GetRopeReader: PUBLIC ENTRY PROC RETURNS [reader: Ref] = { IF roperdr3 # NIL THEN { reader _ roperdr3; roperdr3 _ NIL } ELSE IF roperdr2 # NIL THEN { reader _ roperdr2; roperdr2 _ NIL } ELSE IF roperdr1 # NIL THEN { reader _ roperdr1; roperdr1 _ NIL } ELSE reader _ Create[] }; FreeRopeReader: PUBLIC ENTRY PROC [reader: Ref] = { SetPosition[reader, NIL]; reader.charForEndOfRope _ FALSE; IF roperdr3 = reader OR roperdr2 = reader OR roperdr1 = reader THEN ERROR; IF roperdr3 = NIL THEN roperdr3 _ reader ELSE IF roperdr2 = NIL THEN roperdr2 _ reader ELSE IF roperdr1 = NIL THEN roperdr1 _ reader }; <<-- ***** Initialization>> StartRopeReaderMisc: PUBLIC PROC = TRUSTED { }; END.