[_CDMiwok_01_]<cedarcommon2.0>Waterlily>Waterlily.mesa!8

Waterlily.mesa

Swinehart, November 18, 1985 2:35:32 pm PST

Russ Atkinson (RRA) December 17, 1991 7:43 pm PST

Last tweaked by Mike Spreitzer on October 17, 1988 4:48:07 pm PDT

Bill Jackson (bj) November 17, 1988 5:14:01 pm PST

Jules Bloomenthal August 5, 1991 12:21 pm PDT

Michael Plass, February 21, 1991 9:56 am PST

Willie-s, February 17, 1992 12:51 pm PST

Part of this algorithm cribbed from Heckel, Paul. A Technique For Isolating Differences Between Files. Comm. ACM 21,4 (April 1978), 264-268. Pointer to which courtesy of Ed Taft.

DIRECTORY

BasicTime USING [Now],

Commander USING [CommandProc, Register],

CommanderOps USING [ArgumentVector, Failed, Parse],

EditSpan USING [Copy],

FileNames USING [ResolveRelativePath],

FS USING [defaultStreamOptions, Error, FileInfo, StreamOpen, StreamOptions],

IO USING [Close, EndOfStream, GetBlock, GetCedarToken, GetCedarTokenRope, GetChar, GetIndex, noWhereStream, PeekChar, Put, PutChar, PutF, PutRope, RIS, RopeFromROS, ROS, SetIndex, SkipWhitespace, STREAM, TokenKind],

NodeProps USING [PutProp],

Process USING [CheckForAbort],

PutGet USING [FromFile, WritePlain],

RefText USING [AppendRope, Equal, Fetch, InlineAppendChar, Length, TrustTextAsRope],

Rope USING [Cat, Concat, Equal, Fetch, Flatten, FromRefText, Length, Match, ROPE],

SymTab USING [Create, EachPairAction, Fetch, FetchText, Insert, Pairs, Ref],

TextNode USING [LastWithin, Level, MakeNodeLoc, MakeNodeSpan, NodeRope, Ref, StepForward],

TiogaFileOps USING [AddLooks, CreateRoot, InsertAsLastChild, Ref, SetContents, Store];

Waterlily: CEDAR PROGRAM

IMPORTS BasicTime, Commander, CommanderOps, EditSpan, FileNames, FS, IO, NodeProps, Process, PutGet, RefText, Rope, SymTab, TextNode, TiogaFileOps = {

ROPE: TYPE = Rope.ROPE;

STREAM: TYPE = IO.STREAM;

SymbolTableEntry: TYPE = REF SymbolTableEntryRep;

SymbolTableEntryRep: TYPE = RECORD[

oldList: InstanceList, -- the old instances

newList: InstanceList, -- the new instances

key: ROPE -- the key used for the lookup

];

InstanceList: TYPE = LIST OF InstanceRep;

InstanceRep: TYPE = RECORD [

line: INT, -- -1 => not yet assigned

pos: INT, -- -1 => not yet assigned (node number if mergeFiles)

node: TextNode.Ref←NIL, -- the node, if mergeFiles, instead of line

len: NAT, -- length of original token

peek: CHAR -- non-blank character after this token

];

FileArray: TYPE = REF FileArrayRep;

FileArrayRep: TYPE = RECORD [entry: SEQUENCE index: NAT OF FileArrayEntry];

FileArrayEntry: TYPE = REF FileArrayEntryRep;

FileArrayEntryRep: TYPE = RECORD [

symEntry: SymbolTableEntry,

instance: InstanceList,

otherIndex: INT,

node: TextNode.Ref←NIL,

typeOfPntr: {symTable, lineNum},

len: NAT ← 0];

Ref: TYPE = TextNode.Ref;

Node: TYPE = REF NodeBody;

NodeBody: TYPE = RECORD [root: Ref←NIL, node: Ref←NIL ];

LongHelpMsgW: ROPE =

"Waterlily compares two source files. The command format is one of:
Waterlily file1 file2
Waterlily difFile ← file1 file2
where switches are syntactically before any argument. Differences found are written on the difFile, with default extension '.dif'. The available switches are:
t Tioga format files (default: TRUE)
b Bravo format files (default: FALSE)
u Unformatted files
i Ignore blank lines (default: TRUE)
s Strip digits trailing a ← char (for c2c)
x Output file is a merger of input files (ran out of mnemonics already!)
p Treat Tioga file as plain text (ie, compare comments too)
Input files must be Tioga-format files.
#m # of matching lines (default: 3)
#c # of trailing context lines (default: 1)
";

LongHelpMsgC: ROPE =

"CedarLily compares two Cedar-program source files. Comparison is made at the source-language token level, so that only lexical differences will be found (formatting changes and modified comments will not affect the comparison). The command format is one of:
CedarLily file1 file2
CedarLily difFile ← file1 file2
where switches are syntactically before any argument. Differences found are written on the difFile, with default extension '.dif'. The available switches are:
u Unformatted files
i Ignore blank lines (default: TRUE)
p Treat Tioga file as plain text (ie, compare comments too)
#m # of matching lines (default: 3)
#c # of trailing context lines (default: 1)
";

LongHelpMsgM: ROPE =

"Tigerlily produces a merged version of two Tioga-format files. Nodes unique to file1 are included and indicated by overstriking. Nodes unique to file2 are included and indicated by underlining. Nodes that are common to both files are unchanged. The command format is one of:
Tigerlily file1 file2
Tigerlily mergedFile ← file1 file2
where switches are syntactically before any argument. The merged file is written on the mergedFile, with default extension '.merger'. The available switches are:
p Treat Tioga file as plain text (ie, compare comments too)
#m # of matching lines (default: 3)
#c # of trailing context lines (default: 1)
";

repeats: NAT ← 1;

Make this greater to experiment with multiple phases of match finding

debugging: BOOL ← FALSE;

Turn this on to get different characters for different phases of the process.

WaterlilyProc: Commander.CommandProc = {

PROC [cmd: Handle] RETURNS [result: REF ← NIL, msg: ROPE ← NIL];

Alarm: ERROR = CODE;

oldArray: FileArray;

newArray: FileArray;

out: STREAM ← cmd.out;

pData: REF ← cmd.procData.clientData;

totalNewLines: INT ← 0;

totalOldLines: INT ← 0;

posInNewFile: INT ← 0;

posInOldFile: INT ← 0;

nodeCount: INT ← 0;

newFile: REF; -- IO.STREAM or Node;

oldFile: REF; -- IO.STREAM or Node;

difFile: STREAM;

difFileNode: Node ← NIL;

newFileName: ROPE ← NIL;

oldFileName: ROPE ← NIL;

difFileName: ROPE ← NIL;

Asterisks: ROPE = "**************************************";

filler: ROPE = "->->->->->->";

these switches are global or local.

FileType: TYPE = {tioga, bravo, unform};

switchNewFileType, switchOldFileType: FileType ← tioga;

switchIgnoreEmptyLinesNewFile, switchIgnoreEmptyLinesOldFile: BOOL ← TRUE;

switchTokens: BOOL ← FALSE;

switchMergeFiles: BOOL ← FALSE;

stripLeadingBlanks: BOOL ← FALSE;

stripDigitsTrailingArrow: BOOL ← FALSE;

these switches are global only.

switchLinesForMatch: NAT ← 3;

switchLinesForContext: NAT ← 1;

anyDifferencesSeen: BOOL ← FALSE;

indexN: INT;

indexO: INT;

LineType: TYPE = {new, old, both};

Vintage: TYPE = LineType[new..old];

SetSymbolTableEntry: PROC
[key: ROPE, node: TextNode.Ref, newOrOld: Vintage,
line: INT, pos: INT, len: NAT, peek: CHAR] = {

symTabEntry: SymbolTableEntry ← NIL;

list: InstanceList ← LIST[[line: line, pos: pos, len: len, node: node, peek: peek]];

WITH SymTab.Fetch[symbolTable, key].val SELECT FROM

x: SymbolTableEntry => symTabEntry ← x;

ENDCASE => {

symTabEntry ← NEW[SymbolTableEntryRep ← [

oldList: NIL, newList: NIL, key: key]];

[] ← SymTab.Insert[symbolTable, key, symTabEntry];

};

SELECT newOrOld FROM

new => {

list.rest ← symTabEntry.newList;

symTabEntry.newList ← list;

};

old => {

list.rest ← symTabEntry.oldList;

symTabEntry.oldList ← list;

};

ENDCASE => ERROR;

};

PruneList: PROC [list: InstanceList, pos: INT] RETURNS [pruned: InstanceList] = {

IF list = NIL THEN RETURN [NIL];

IF list.first.pos = pos THEN RETURN [list.rest];

pruned ← list;

lag: InstanceList ← list;

list ← list.rest;

IF list = NIL THEN RETURN;

IF list.first.pos = pos THEN {lag.rest ← list.rest; RETURN};

ENDLOOP;

};

ConnectEntries: PROC [symTabEntry: SymbolTableEntry, indexO, indexN: INT, entryO, entryN: FileArrayEntry] = {

entryN.typeOfPntr ← entryO.typeOfPntr ← lineNum;

entryN.otherIndex ← indexO;

entryO.otherIndex ← indexN;

symTabEntry.newList ← PruneList[symTabEntry.newList, entryN.instance.first.pos];

symTabEntry.oldList ← PruneList[symTabEntry.oldList, entryO.instance.first.pos];

};

EndOfFile: ERROR = CODE;

token: REF TEXT ← NEW[TEXT[128]];

GetLine: PROC [stream: STREAM, token: REF TEXT] RETURNS [REF TEXT] = {

token.length ← 0;

c: CHAR;

IF lineBufferPos >= lineBufferLen THEN {

We need a new buffer

lineBuffer.length ← 0;

lineBufferLen ← IO.GetBlock[stream, lineBuffer, 0, lineBufferSize

! IO.EndOfStream => EXIT];

IF lineBufferLen = 0 THEN {

We are at the end of the stream. If the token is empty, then raise EndOfStream.

IF token.length = 0 THEN ERROR IO.EndOfStream[stream];

EXIT;

};

lineBuffer.length ← lineBufferLen;

lineBufferPos ← 0;

};

c ← lineBuffer[lineBufferPos];

lineBufferPos ← lineBufferPos + 1;

inputPos ← inputPos + 1;

IF IsEndOfLine[c] THEN EXIT;

token ← RefText.InlineAppendChar[token, c];

ENDLOOP;

RETURN [token];

};

lineBufferSize: NAT ← 1024;

lineBuffer: REF TEXT ← NEW[TEXT[lineBufferSize]];

lineBufferPos: NAT ← 0;

lineBufferLen: NAT ← 0;

inputPos: INT ← 0;

ReadLineFromFile: PROC
[source: REF, localFileType: FileType, localIgnoreEmpties: BOOL]
RETURNS [key: ROPE, node: TextNode.Ref, peek: CHAR, pos: INT, len: NAT] = {

SetToken: PROC [value: ROPE, append: BOOL ← FALSE] = {

IF NOT append THEN token.length ← 0;

token ← RefText.AppendRope[token, value];

};

in: STREAM;

inNode: Node;

WITH source SELECT FROM

str: STREAM => in ← str;

ref: Node => inNode ← ref;

ENDCASE => ERROR;

key ← NIL;

node ← NIL;

pos ← -1;

len ← 0;

peek ← 0C;

Process.CheckForAbort[];

SELECT pData FROM

$Cedar => {

Special processing for Cedar tokens

kind: IO.TokenKind;

token.length ← 0;

[] ← IO.SkipWhitespace[stream: in, flushComments: TRUE

! IO.EndOfStream => CONTINUE];

pos ← IO.GetIndex[in];

[tokenKind: kind, token: token, charsSkipped: ] ← IO.GetCedarToken[in, token

! IO.EndOfStream => ERROR EndOfFile];

IF kind = tokenEOF THEN ERROR EndOfFile;

len ← IO.GetIndex[in] - pos;

Now do a little canonicalization to avoid reporting meaningless differences.

SELECT kind FROM

tokenROPE => {

len: NAT ~ RefText.Length[token];

lastChar: CHAR ~ IF ( len # 0 ) THEN RefText.Fetch[token, len.PRED] ELSE 0C;

SELECT lastChar FROM

'L => { token.length ← len.PRED }; -- disregard frame specifiers for strings!

'G => { token.length ← len.PRED }; -- disregard frame specifiers for strings!

ENDCASE;

};

tokenSINGLE => {

char: CHAR ← token[0];

SELECT char FROM

'← => token[0] ← '¬; -- Character code finesse

'^ => token[0] ← '; -- Character code finesse

'; => LOOP;

Semicolons are quite common, but not very important, and are often optional. So we can safely ignore them.

'} => {

This may just be the end of the interesting part of the file.

[] ← IO.SkipWhitespace[stream: in, flushComments: TRUE

! IO.EndOfStream => CONTINUE];

peek ← IO.PeekChar[in

! IO.EndOfStream => {peek ← 0C; CONTINUE}];

IF peek = '. THEN ERROR EndOfFile;

};

ENDCASE;

};

tokenID => {

char: CHAR ← token[0];

[] ← IO.SkipWhitespace[stream: in, flushComments: TRUE

! IO.EndOfStream => CONTINUE];

peek ← IO.PeekChar[in

! IO.EndOfStream => {peek ← 0C; CONTINUE}];

SELECT char FROM

'B => SELECT TRUE FROM

RefText.Equal[token, "BEGIN"] => SetToken["{"];

RefText.Equal[token, "BOOLEAN"] => SetToken["BOOL"];

ENDCASE;

'C => SELECT TRUE FROM

RefText.Equal[token, "CHARACTER"] => SetToken["CHAR"];

RefText.Equal[token, "CARD"] => SetToken["CARD32"];

ENDCASE;

'E => SELECT TRUE FROM

RefText.Equal[token, "END"] => {

This may just be the end of the interesting part of the file.

SetToken["}"];

IF peek = '. THEN ERROR EndOfFile;

};

ENDCASE;

'I => SELECT TRUE FROM

RefText.Equal[token, "INT"] => SetToken["INT32"];

ENDCASE;

'L => SELECT TRUE FROM

RefText.Equal[token, "LONG"] => {

key ← IO.GetCedarTokenRope[in].token;

SELECT TRUE FROM

Rope.Equal[key, "CARDINAL"] => SetToken["CARD32"];

Rope.Equal[key, "INTEGER"] => SetToken["INT32"];

ENDCASE => {SetToken["LONG "]; SetToken[key, TRUE]};

};

ENDCASE;

'P => SELECT TRUE FROM

RefText.Equal[token, "PROCEDURE"] => SetToken["PROC"];

ENDCASE;

This is an interesting little hack. It tends to improve token uniqueness by appending the peek character, tends to reduce the number of tokens in the table (by swallowing lots of single-character tokens), and thereby improves matching.

SELECT peek FROM

'← => {

Character code finesse

ch: CHAR ← IO.GetChar[in];

peek ← '¬;

};

'^ => {

Character code finesse

ch: CHAR ← IO.GetChar[in];

peek ← ';

};

':, '¬, ', '., ',, '~ => {

peek ← IO.GetChar[in];

};

ENDCASE => GO TO noHack;

token ← RefText.InlineAppendChar[token, peek];

len ← IO.GetIndex[in] - pos;

EXITS noHack => {};

};

ENDCASE;

WITH SymTab.FetchText[symbolTable, token].val SELECT FROM

symTabEntry: SymbolTableEntry => key ← symTabEntry.key;

ENDCASE => key ← Rope.FromRefText[token];

EXIT;

};

ENDCASE;

We only get here when we are using full lines as tokens.

IF switchMergeFiles

THEN {

pos ← nodeCount;

nodeCount ← nodeCount+1;

node ← inNode.node ← inNode.node.StepForward[];

IF node = NIL THEN ERROR EndOfFile;

token.length ← 0;

token ← RefText.AppendRope[token, node.NodeRope[]];

}

ELSE {

pos ← inputPos;

token ← GetLine[in, token ! IO.EndOfStream => ERROR EndOfFile];

len ← token.length;

};

IF stripDigitsTrailingArrow OR stripLeadingBlanks OR localFileType = bravo THEN {

Here we process the token to make it canonical

srcPos: NAT ← 0;

dstPos: NAT ← 0;

tLen: NAT = token.length;

IF stripLeadingBlanks THEN

WHILE srcPos < tLen DO

SELECT token[srcPos] FROM

' , '\t => srcPos ← srcPos + 1;

ENDCASE => EXIT;

ENDLOOP;

IF stripDigitsTrailingArrow OR localFileType = bravo THEN {

skipDigits: BOOL ← FALSE;

WHILE srcPos < tLen DO

c: CHAR ← token[srcPos];

srcPos ← srcPos + 1;

SELECT c FROM

'← => skipDigits ← stripDigitsTrailingArrow;

IN ['0..'9] => IF skipDigits THEN LOOP;

'\032 => IF localFileType = bravo THEN EXIT;

ENDCASE => skipDigits ← FALSE;

token[dstPos] ← c;

dstPos ← dstPos + 1;

ENDLOOP;

};

len ← srcPos;

IF stripLeadingBlanks THEN

WHILE dstPos # 0 DO

SELECT token[dstPos-1] FROM

' , '\t => dstPos ← dstPos - 1;

ENDCASE => EXIT;

ENDLOOP;

token.length ← dstPos;

};

WITH SymTab.FetchText[symbolTable, token].val SELECT FROM

symTabEntry: SymbolTableEntry => key ← symTabEntry.key;

ENDCASE => key ← Rope.FromRefText[token];

IF localIgnoreEmpties THEN {

FOR i: NAT IN [0..token.length) DO

SELECT token[i] FROM

' , '\t => {};

ENDCASE => GO TO Gotit;

ENDLOOP;

peek ← peek;

}

ELSE GOTO Gotit;

ENDLOOP;

len ← len;

EXITS Gotit => pos ← pos

};

FinishUp: PROC [difMsg: ROPE] = {

IO.PutRope[out, difMsg];

IO.PutRope[out, "\n"];

IF switchMergeFiles THEN RETURN;

IF difFile = NIL THEN OpenDifFileAndWriteHeader[];

IO.PutRope[difFile, difMsg];

IO.PutRope[difFile, "\n"];

IO.Close[difFile];

};

WorkingMsg: PROC [char: CHAR] = {

Process.CheckForAbort[];

IO.PutChar[out, IF debugging THEN char ELSE '.];

};

OpenDifFileAndWriteHeader: PROC = {

IF anyDifferencesSeen THEN RETURN;

anyDifferencesSeen ← TRUE;

difFileName ← DefaultExtension[difFileName,
IF switchMergeFiles THEN ".merger" ELSE ".dif", TRUE];

IF switchMergeFiles THEN {

difFile ← IO.noWhereStream;

difFileNode ← NewNode[];

RETURN;

};

difFile ← FS.StreamOpen[difFileName, $create];

IO.PutRope[difFile, IF pData = $Cedar THEN "\nCedarlily" ELSE "\nWaterlily"];

IO.PutF[difFile, "\n run on %g\n File 1: %g\n File 2: %g\n\n",

[time[BasicTime.Now[]]], [rope[oldFileName]], [rope[newFileName]]];

};

OpenFile: PROC [tempFileName: ROPE, switchFileType: FileType, writePlain: BOOL]
RETURNS [fileName: ROPE, file: REF] = {

streamOptions: FS.StreamOptions ← FS.defaultStreamOptions;

streamOptions[tiogaRead] ← (switchFileType = tioga);

tempFileName ← DefaultExtension[tempFileName, ".mesa", FALSE];

fileName ← FS.FileInfo[tempFileName].fullFName;

SELECT TRUE FROM

switchMergeFiles => file ← NodeFromFile[fileName];

writePlain => {

root: TextNode.Ref ← PutGet.FromFile[fileName];

s: IO.STREAM ← IO.ROS[];

PutGet.WritePlain[s, root];

file ← IO.RIS[IO.RopeFromROS[s]];

};

ENDCASE => file ← FS.StreamOpen[fileName, $read, streamOptions];

};

start here.

symbolTable: SymTab.Ref ← SymTab.Create[mod: 1023, case: TRUE];

fillerNode: Node ← NewNode[];

fillerNode.node ← TR[TiogaFileOps.InsertAsLastChild[FR[fillerNode.root]]];

TiogaFileOps.SetContents[FR[fillerNode.node], filler];

TiogaFileOps.AddLooks[FR[fillerNode.node], 0, filler.Length[], 'b, FR[fillerNode.root]];

NodeProps.PutProp[fillerNode.node, $Comment, NEW[BOOL←TRUE]];

result ← NIL;

msg ← NIL;

Process arguments

{

args: CommanderOps.ArgumentVector ← CommanderOps.Parse[cmd

! CommanderOps.Failed => {msg ← "Syntax error."; GO TO fatalError}

];

fileCount: NAT ← 0;

writePlain: BOOL ← FALSE;

defaultFileType: FileType ← tioga;

ignoreEmptyLines: BOOL ← TRUE;

IF pData=$Merge THEN { switchMergeFiles ← TRUE; ignoreEmptyLines ← FALSE; };

FOR i: NAT IN [1..args.argc) DO

arg: ROPE = args[i];

sense: BOOL ← TRUE;

IF Rope.Match["-*", arg] THEN {

Switches specified here

len: NAT ← Rope.Length[arg];

number: INT ← 0;

FOR i: NAT IN [1..len) DO

c: CHAR ← Rope.Fetch[arg, i];

SELECT c FROM

'~ => sense ← NOT sense;

'b, 'B => defaultFileType ← bravo;

't, 'T => defaultFileType ← tioga;

'u, 'U => defaultFileType ← unform;

'i, 'I => ignoreEmptyLines ← sense;

's, 'S => stripDigitsTrailingArrow ← stripLeadingBlanks ← sense;

'x, 'X => {

switchMergeFiles ← sense;

IF sense THEN ignoreEmptyLines ← FALSE;

};

IN ['0..'9] => {number ← number*10 + (c-'0); LOOP};

'm, 'M => IF number >= 1 THEN switchLinesForMatch ← number;

'c, 'C => IF number >= 1 THEN switchLinesForContext ← number;

'p, 'P => writePlain ← TRUE;

ENDCASE;

number ← 0;

ENDLOOP;

LOOP;

};

IF Rope.Match["←", arg] THEN {

The old file name is really the dif file name

IF fileCount # 1 THEN GO TO usageError;

fileCount ← 0;

difFileName ← oldFileName;

LOOP;

};

SELECT fileCount FROM

0 => {

fileCount ← 1;

switchOldFileType ← defaultFileType;

switchIgnoreEmptyLinesOldFile ← ignoreEmptyLines;

oldFileName ← FileNames.ResolveRelativePath[arg];

IF difFileName = NIL THEN difFileName ← ShortName[arg];

};

1 => {

fileCount ← 2;

switchNewFileType ← defaultFileType;

switchIgnoreEmptyLinesNewFile ← ignoreEmptyLines;

newFileName ← FileNames.ResolveRelativePath[arg];

};

ENDCASE => {GO TO usageError};

ENDLOOP;

IF fileCount # 2 THEN GO TO usageError;

out.PutRope["Comparing "];

{

ENABLE FS.Error => {

IF error.group # bug THEN msg ← error.explanation;

GO TO fatalError;

};

[oldFileName, oldFile] ← OpenFile[oldFileName, switchOldFileType, writePlain];

[newFileName, newFile] ← OpenFile[newFileName, switchNewFileType, writePlain];

};

WorkingMsg['-];

};

Pass 1 & 2

{

Pass 1

In Pass 1 we scan the new file (the second one mentioned in the command line) for lines (or tokens), and enter them into the symbol table.

nextLine: ROPE ← NIL;

nextNode: TextNode.Ref ← NIL;

peek: CHAR;

inputPos ← 0;

lineBufferLen ← 0;

lineBufferPos ← 0;

key: ROPE;

len: NAT;

[key, nextNode, peek, posInNewFile, len] ← ReadLineFromFile[newFile, switchNewFileType, switchIgnoreEmptyLinesNewFile

! EndOfFile => EXIT];

SetSymbolTableEntry[key, nextNode, new, totalNewLines, posInNewFile, len, peek];

totalNewLines ← totalNewLines + 1;

ENDLOOP;

IF totalNewLines = 0 THEN GOTO emptyfile;

newArray ← NEW[FileArrayRep[totalNewLines]];

WorkingMsg['!];

Pass 2

Pass 2 is like Pass1, except that we are scanning the old file (the first one mentioned in the command line).

inputPos ← 0;

lineBufferLen ← 0;

lineBufferPos ← 0;

key: ROPE;

len: NAT;

[key, nextNode, peek, posInOldFile, len] ← ReadLineFromFile[oldFile, switchOldFileType, switchIgnoreEmptyLinesOldFile

! EndOfFile => EXIT];

SetSymbolTableEntry[key, nextNode, old, totalOldLines, posInOldFile, len, peek];

totalOldLines ← totalOldLines + 1;

ENDLOOP;

IF totalOldLines = 0 THEN GOTO emptyfile;

oldArray ← NEW[FileArrayRep[totalOldLines]];

WorkingMsg['@];

Pass 3

In Pass 3 we transform all of the instances into file array entries.

{

Test: SymTab.EachPairAction = {

[key: SymTab.Key, val: SymTab.Val] RETURNS [quit: BOOL]

symTabEntry: SymbolTableEntry ← NARROW[val];

newList: InstanceList ← symTabEntry.newList;

oldList: InstanceList ← symTabEntry.oldList;

FOR each: InstanceList ← newList, each.rest WHILE each # NIL DO

newArray[each.first.line] ← NEW[FileArrayEntryRep ← [

symEntry: symTabEntry,

instance: each,

otherIndex: -1,

node: each.first.node,

typeOfPntr: symTable,

len: each.first.len]];

ENDLOOP;

FOR each: InstanceList ← oldList, each.rest WHILE each # NIL DO

oldArray[each.first.line] ← NEW[FileArrayEntryRep ← [

symEntry: symTabEntry,

instance: each,

otherIndex: -1,

node: each.first.node,

typeOfPntr: symTable,

len: each.first.len]];

ENDLOOP;

RETURN[FALSE];

};

[] ← SymTab.Pairs[symbolTable, Test];

WorkingMsg['#];

};

EXITS emptyfile => {

FinishUp["At least one of these files is effectively empty."];

RETURN;

};

THROUGH [0..repeats) DO

Pass 4

In Pass 4 we run through the symbol table to connect all lines (or tokens) that appear only once in both files (OR appear once with a given peek char). Those lines (or tokens) are the places where the files are known to coincide.

{

Test: SymTab.EachPairAction = {

[key: SymTab.Key, val: SymTab.Val] RETURNS [quit: BOOL]

symTabEntry: SymbolTableEntry ← NARROW[val];

newList: InstanceList ← symTabEntry.newList;

oldList: InstanceList ← symTabEntry.oldList;

Process.CheckForAbort[];

SELECT TRUE FROM

newList = NIL, oldList = NIL => {};

newList.rest # NIL, oldList.rest # NIL => {

};

ENDCASE => {

indexO ← oldList.first.line;

indexN ← newList.first.line;

ConnectEntries[symTabEntry, indexO, indexN, oldArray[indexO], newArray[indexN]];

};

RETURN[FALSE];

};

[] ← SymTab.Pairs[symbolTable, Test];

WorkingMsg['$];

};

Pass 5

In Pass 5 we extend matching entries outwards by scanning forwards.

{

indexN ← 0;

WHILE indexN < totalNewLines DO

entry: FileArrayEntry = newArray[indexN];

Process.CheckForAbort[];

indexN ← indexN + 1;

IF entry.typeOfPntr = lineNum THEN {

indexO ← entry.otherIndex + 1;

WHILE indexN < totalNewLines AND indexO < totalOldLines DO

entryN: FileArrayEntry = newArray[indexN];

entryO: FileArrayEntry = oldArray[indexO];

symEntry: SymbolTableEntry ← entryN.symEntry;

SELECT TRUE FROM

entryN.typeOfPntr = symTable
AND entryO.typeOfPntr = symTable
AND symEntry = entryO.symEntry =>

ConnectEntries[symEntry, indexO, indexN, entryO, entryN];

entryN.typeOfPntr # lineNum
OR entryO.typeOfPntr # lineNum
OR entryN.otherIndex # indexO
OR entryO.otherIndex # indexN => EXIT;

ENDCASE;

indexN ← indexN + 1;

indexO ← indexO + 1;

ENDLOOP;

};

ENDLOOP;

WorkingMsg['%];

};

Pass 6

In Pass 6 we extend matching entries outwards by scanning backwards.

{

indexN ← totalNewLines - 1;

WHILE indexN >= 0 DO

entry: FileArrayEntry = newArray[indexN];

Process.CheckForAbort[];

indexN ← indexN - 1;

IF entry.typeOfPntr = lineNum THEN {

indexO ← entry.otherIndex - 1;

WHILE indexN >= 0 AND indexO >= 0 DO

entryN: FileArrayEntry = newArray[indexN];

entryO: FileArrayEntry = oldArray[indexO];

symEntry: SymbolTableEntry ← entryN.symEntry;

Process.CheckForAbort[];

SELECT TRUE FROM

entryN.typeOfPntr = symTable
AND entryO.typeOfPntr = symTable
AND symEntry = entryO.symEntry => {

ConnectEntries[symEntry, indexO, indexN, entryO, entryN];

};

entryN.typeOfPntr # lineNum
OR entryO.typeOfPntr # lineNum
OR entryN.otherIndex # indexO
OR entryO.otherIndex # indexN =>

EXIT;

ENDCASE;

indexN ← indexN - 1;

indexO ← indexO - 1;

ENDLOOP;

};

ENDLOOP;

WorkingMsg['~];

};

ENDLOOP;

Passes 7 and 8

{

CancelMatch: PROC [array1, array2: FileArray, totalNumOfLinesFile1, index: INT] = {

entry1: FileArrayEntry ← array1[index];

IF entry1.typeOfPntr = symTable THEN EXIT;

entry1.typeOfPntr ← symTable;

array2[entry1.otherIndex].typeOfPntr ← symTable;

index ← index + 1;

IF ((index >= totalNumOfLinesFile1)
OR (entry1.otherIndex # array1[index - 1].otherIndex + 1)) THEN EXIT;

ENDLOOP;

};

Pass 7

In Pass 7 we cancel matches that don't extend far enough. This is to prevent excessive context switching in reporting differences.

IF switchLinesForMatch > 1 THEN {

indexN ← 0;

oldIndexN: INT ← indexN;

indexN ← indexN + 1;

Process.CheckForAbort[];

IF indexN >= totalNewLines THEN EXIT;

IF newArray[indexN].typeOfPntr = lineNum THEN {

WHILE ((indexN < totalNewLines)
AND (newArray[indexN].otherIndex = newArray[indexN-1].otherIndex + 1)) DO

indexN ← indexN + 1;

ENDLOOP;

IF (indexN - oldIndexN) < switchLinesForMatch AND indexN < totalNewLines THEN

CancelMatch[newArray, oldArray, totalNewLines, oldIndexN];

};

ENDLOOP;

};

WorkingMsg['&];

Pass 8

In Pass 8 we actually print the differences, skipping over the matches.

{

LeadingNumber: PROC [char: CHAR, number: INT] = {

must be a better way to do this.

leadingZeroes: INTEGER ← columns - 1;

tempIndex: INT ← number;

IF switchMergeFiles THEN RETURN;

Process.CheckForAbort[];

difFile.PutF["%g/", [character[char]]];

IF tempIndex < 10 THEN EXIT;

tempIndex ← tempIndex/10;

leadingZeroes ← leadingZeroes - 1;

ENDLOOP;

THROUGH [0..leadingZeroes) DO difFile.PutChar['0]; ENDLOOP;

difFile.Put[[integer[number]]];

difFile.PutRope[") "];

};

PrintDelta: PROC [file: REF, which: CHAR, entry: FileArrayEntry] = {

Dump out the line indicated by the entry

st: STREAM = NARROW[file];

pos: INT = entry.instance.first.pos;

LeadingNumber[which, pos];

IO.SetIndex[st, pos];

THROUGH [0..entry.len) DO

c: CHAR ← IO.GetChar[st ! IO.EndOfStream => EXIT];

IO.PutChar[difFile, c];

ENDLOOP;

IO.PutChar[difFile, '\n];

};

PrintCedarDelta: PROC [file: REF, index, start, total: INT, array: FileArray]
RETURNS [INT] = {

Dump out the difference indicated, extending the difference through the start of the line containing the first token, and through the end of the line containing the last token. Return the index after the last token on the last line printed.

st: STREAM = NARROW[file];

IF start < total THEN {

leadChar: CHAR ← IF file = oldFile THEN '1 ELSE '2;

lastChar: CHAR ← 0C;

lastIndex: INT ← MIN[index+1, total] - 1;

lastEntry: FileArrayEntry = array[lastIndex];

pos: INT ← array[start].instance.first.pos;

end: INT ← lastEntry.instance.first.pos+lastEntry.instance.first.len;

First, get to the preceding line start by scanning backwards

WHILE pos > 0 DO

IO.SetIndex[st, pos - 1];

lastChar ← IO.GetChar[st];

IF IsEndOfLine[lastChar] THEN EXIT;

pos ← pos - 1;

ENDLOOP;

Now, put out lines until the rem count is exhausted

LeadingNumber[leadChar, pos];

IO.SetIndex[st, pos];

lastChar ← IO.GetChar[st ! IO.EndOfStream => EXIT];

IF IsEndOfLine[lastChar]

THEN {

IF pos >= end THEN EXIT;

IO.PutChar[difFile, '\n];

LeadingNumber[leadChar, pos];

}

ELSE IO.PutChar[difFile, lastChar];

pos ← pos + 1;

ENDLOOP;

IO.PutChar[difFile, '\n];

Now skip over tokens we inadvertently covered during our printing to the end of line. The index returned is the one after the one we printed.

WHILE index < total DO

IF array[index].instance.first.pos >= end THEN EXIT;

index ← index + 1;

ENDLOOP;

};

RETURN [index];

};

DumpOutDiffAndMoveAhead: PROC = {

IF NOT anyDifferencesSeen THEN {

OpenDifFileAndWriteHeader[];

difFile.PutF["%g%g\n", [rope[Asterisks]], [rope[Asterisks]]];

};

SELECT TRUE FROM

(indexN >= totalNewLines) OR (indexO >= totalOldLines) => {

indexN ← totalNewLines;

indexO ← totalOldLines;

};

newArray[indexN].typeOfPntr = lineNum =>

indexO ← newArray[indexN].otherIndex

ENDCASE =>

indexN ← oldArray[indexO].otherIndex;

SELECT pData FROM

$Cedar => {

indexO ← PrintCedarDelta[oldFile, indexO, startDifO, totalOldLines, oldArray];

difFile.PutF["%g\n", [rope[Asterisks]]];

indexN ← PrintCedarDelta[newFile, indexN, startDifN, totalNewLines, newArray];

};

ENDCASE => {

IF switchMergeFiles

THEN CopySpan[oldArray, startDifO, indexO-1, oldFile, old, totalOldLines]

ELSE {

FOR index: INT IN [startDifO..indexO) DO

entry: FileArrayEntry = oldArray[index];

PrintDelta[oldFile, '1, entry];

ENDLOOP;

FOR index: INT IN [indexO..indexO + switchLinesForContext)
WHILE (index < totalOldLines) DO

entry: FileArrayEntry = oldArray[index];

PrintDelta[oldFile, '1, entry];

ENDLOOP;

};

indexO ← indexO + switchLinesForContext;

difFile.PutF["%g\n", [rope[Asterisks]]];

IF switchMergeFiles

THEN CopySpan[newArray, startDifN, indexN-1, newFile, new, totalNewLines]

ELSE {

FOR index: INT IN [startDifN..indexN) DO

entry: FileArrayEntry = newArray[index];

PrintDelta[newFile, '2, entry];

ENDLOOP;

FOR index: INT IN [indexN..indexN + switchLinesForContext)
WHILE (index < totalNewLines) DO

entry: FileArrayEntry = newArray[index];

PrintDelta[newFile, '2, entry];

ENDLOOP;

};

indexN ← indexN + switchLinesForContext;

};

difFile.PutF["\n%g%g\n", [rope[Asterisks]], [rope[Asterisks]]];

If merging, print the context lines here.

IF switchMergeFiles THEN

CopySpan[newArray, indexN-switchLinesForContext, indexN-1, newFile, both, totalNewLines];

Move ahead to get beyond the last line from the old file.

startDifN ← indexN;

WHILE indexN < totalNewLines AND newArray[indexN].typeOfPntr # symTable DO

IF newArray[indexN].otherIndex
# newArray[indexN - 1].otherIndex + 1 THEN EXIT;

indexN ← indexN + 1;

indexO ← indexO + 1;

ENDLOOP;

IF switchMergeFiles AND indexN>startDifN THEN

CopySpan[newArray, startDifN, indexN-1, newFile, both, totalNewLines];

startDifN ← indexN;

startDifO ← indexO;

};

TryToResolveConflicts: PROC [array1, array2: FileArray, index1, index2: INT]
RETURNS [okToDumpDiff: BOOL] = {

entry1: FileArrayEntry ← array1[index1];

lastRange1: INT ← index1 + entry1.otherIndex - index2;

FOR tempIndex: INT IN [index2..entry1.otherIndex) DO

entry2: FileArrayEntry ← array2[tempIndex];

IF entry2.typeOfPntr = lineNum THEN {

IF entry2.otherIndex > lastRange1

THEN CancelMatch[array2, array1, totalOldLines, tempIndex]

ELSE {

CancelMatch[array1, array2, totalNewLines, index1];

RETURN[FALSE];

};

ENDLOOP;

RETURN [TRUE];

};

CopySpan: PROC [array: FileArray, index1, index2: INT, in: REF, lineType: LineType ← both, limit: INT←-1] = {

inNode: Node = NARROW[in];

nesting: INT;

IF limit>=0 THEN { IF index1 >= limit THEN RETURN; index2 ← MIN[index2, limit-1]; };

IF index1>index2 THEN RETURN;

nesting ← TextNode.Level[array[index1].node] - TextNode.Level[difFileNode.node];

WHILE nesting > 1 DO

[]�itSpan.Copy[difFileNode.root, fillerNode.root, TextNode.MakeNodeLoc[difFileNode.node], TextNode.MakeNodeSpan[fillerNode.node, fillerNode.node], after, 1];

nesting ← nesting - 1;

ENDLOOP;

[]�itSpan.Copy[difFileNode.root, inNode.root, TextNode.MakeNodeLoc[difFileNode.node], TextNode.MakeNodeSpan[array[index1].node, array[index2].node], after, nesting];

IF lineType=both

THEN difFileNode.node ← TextNode.LastWithin[difFileNode.root]

ELSE {

node: TextNode.Ref;

WHILE (node←TextNode.StepForward[difFileNode.node])#NIL DO

len: INT = Rope.Length[TextNode.NodeRope[node]];

difFileNode.node ← node;

SELECT lineType FROM

old => TiogaFileOps.AddLooks[FR[node], 0, len, 'y];

new => TiogaFileOps.AddLooks[FR[node], 0, len, 'z];

ENDCASE;

ENDLOOP;

};

startDifN: INT;

startDifO: INT;

dumpDiff: BOOL;

columns: NAT ← 1;

max: INT ← MAX[posInNewFile, posInOldFile];

IF max < 10 THEN EXIT;

max ← max/10;

columns ← columns + 1;

ENDLOOP;

indexN ← 0;

indexO ← 0;

IF switchMergeFiles THEN OpenDifFileAndWriteHeader[];

IF indexN >= totalNewLines OR indexO >= totalOldLines

THEN EXIT

ELSE {

entryN: FileArrayEntry ← newArray[indexN];

entryO: FileArrayEntry ← oldArray[indexO];

IF entryN.typeOfPntr # lineNum THEN EXIT;

IF entryO.typeOfPntr # lineNum THEN EXIT;

IF entryN.otherIndex # indexO THEN EXIT;

IF entryO.otherIndex # indexN THEN EXIT;

indexN ← indexN + 1;

indexO ← indexO + 1;

};

ENDLOOP;

IF switchMergeFiles AND indexN>0 THEN

CopySpan[newArray, 0, indexN-1, newFile, both];

startDifN ← indexN;

startDifO ← indexO;

dumpDiff ← FALSE;

WHILE ((indexN < totalNewLines) AND (indexO < totalOldLines)) DO

entryN: FileArrayEntry = newArray[indexN];

entryO: FileArrayEntry = oldArray[indexO];

IF entryN.typeOfPntr = lineNum OR entryO.typeOfPntr = lineNum THEN {

IF entryN.typeOfPntr = lineNum AND entryO.typeOfPntr = lineNum THEN {

IF entryN.otherIndex = indexO AND entryO.otherIndex = indexN THEN GOTO dumpoutthedifference;

IF (entryN.otherIndex - indexO) > (entryO.otherIndex - indexN)

THEN CancelMatch[newArray, oldArray, totalNewLines, indexN]

ELSE CancelMatch[oldArray, newArray, totalOldLines, indexO];

};

IF entryN.typeOfPntr = lineNum

THEN dumpDiff ← TryToResolveConflicts[newArray, oldArray, indexN, indexO]

ELSE dumpDiff ← TryToResolveConflicts[oldArray, newArray, indexO, indexN];

EXITS dumpoutthedifference => dumpDiff ← TRUE;

};

IF dumpDiff

THEN {

DumpOutDiffAndMoveAhead[];

dumpDiff ← FALSE;

}

ELSE {

indexN ← indexN + 1;

indexO ← indexO + 1;

};

ENDLOOP;

IF startDifN < totalNewLines OR startDifO < totalOldLines THEN

DumpOutDiffAndMoveAhead[];

WorkingMsg['*];

IF switchMergeFiles THEN TiogaFileOps.Store[FR[difFileNode.root], difFileName];

};

IF anyDifferencesSeen

THEN FinishUp[Rope.Cat[IF switchMergeFiles THEN "merged version written on file " ELSE " differences written on file ", difFileName, ".\n"]]

ELSE {FinishUp[" no differences encountered.\n"]; result ← $NoAction};

IF ~switchMergeFiles THEN {

IO.Close[NARROW[oldFile]];

IO.Close[NARROW[newFile]];

}

};

EXITS

usageError => {msg ← "Usage error: Waterlily file1 file2\n"; result ← $Failure};

fatalError => {result ← $Failure};

};

ShortName: PROC [name: ROPE] RETURNS [ROPE] = {

bang: INT ← Rope.Length[name];

pos: INT ← bang;

WHILE (pos ← pos - 1) > 0 DO

SELECT Rope.Fetch[name, pos] FROM

'>, '/, '] => {pos ← pos + 1; EXIT};

'!, '. => bang ← pos;

ENDCASE;

ENDLOOP;

RETURN [Rope.Flatten[name, pos, bang - pos]];

};

DefaultExtension: PROC [name: ROPE, ext: ROPE, forceExt: BOOL] RETURNS [ROPE] = {

len: INT ← Rope.Length[name];

pos: INT ← len;

WHILE (pos ← pos - 1) > 0 DO

SELECT Rope.Fetch[name, pos] FROM

'>, '/, '] => EXIT;

'., '! => RETURN [name];

ENDCASE;

ENDLOOP;

IF forceExt THEN RETURN[Rope.Concat[name, ext]];

[] ← FS.FileInfo[name ! FS.Error => GOTO NoFile];

RETURN [name]; -- if file exists, don't change its name

EXITS NoFile => RETURN[Rope.Concat[name, ext]];

};

Node Management

TR: PROC[ref: REF] RETURNS [TextNode.Ref] = TRUSTED INLINE {

RETURN[LOOPHOLE[ref]]; };

FR: PROC[ref: REF] RETURNS [TiogaFileOps.Ref] = TRUSTED INLINE {

RETURN[LOOPHOLE[ref]]; };

NewNode: PROC RETURNS [node: Node] = {

node ← NEW[NodeBody ← [TR[TiogaFileOps.CreateRoot[]]]];

node.node ← node.root;

NodeProps.PutProp[n: NARROW[node.root, TextNode.Ref], name: $NewlineDelimiter, value: Rope.Flatten["\n"]];

};

NodeFromFile: PROC[fileName: ROPE] RETURNS [node: Node] = {

node ← NEW[NodeBody ← []];

node.root ← PutGet.FromFile[fileName];

node.node ← node.root;

};

IsEndOfLine: PROC [c: CHAR] RETURNS [BOOL] = INLINE {

RETURN [c = '\n OR c = 015C OR c = 012C];

};

Commander.Register[key: "Waterlily", proc: WaterlilyProc, doc: LongHelpMsgW, clientData: NIL];

Commander.Register[key: "Cedarlily", proc: WaterlilyProc, doc: LongHelpMsgC, clientData: $Cedar];

Commander.Register[key: "Tigerlily",

proc: WaterlilyProc, doc: LongHelpMsgM, clientData: $Merge];

Commander.Register[key: "MergeLily",

proc: WaterlilyProc, doc: LongHelpMsgM, clientData: $Merge]; -- The old name