public IWhitespaceManager GetOrCreateWhitespaceManager(
ITextBuffer buffer,
NewlineState initialNewlineState,
LeadingWhitespaceState initialLeadingWhitespaceState)
{
return(buffer.Properties.GetOrCreateSingletonProperty(
typeof(IWhitespaceManager),
() => new WhitespaceManager(buffer, initialNewlineState, initialLeadingWhitespaceState)));
}
public WhitespaceManager(ITextBuffer documentBuffer, NewlineState newlineState, LeadingWhitespaceState leadingWhitespaceState)
{
documentBuffer.Changed += this.OnDocumentBufferChanged;
NewlineState = newlineState;
LeadingWhitespaceState = leadingWhitespaceState;
}
internal static StringRebuilder Load(TextReader reader, long fileSize,
out NewlineState newlineState,
out LeadingWhitespaceState leadingWhitespaceState,
out int longestLineLength,
int blockSize = 0,
int minCompressedBlockSize = TextImageLoader.BlockSize, // Exposed for unit tests
bool throwOnInvalidCharacters = false)
{
newlineState = new NewlineState();
leadingWhitespaceState = new LeadingWhitespaceState();
int currentLineLength = 0;
longestLineLength = 0;
char thresholdForInvalidCharacters = throwOnInvalidCharacters ? '\u0001' : '\0'; // Basically the only invalid character is \0, if we are looking for invalid characters.
bool useCompressedStringRebuilders = (fileSize >= TextModelOptions.CompressedStorageFileSizeThreshold);
if (blockSize == 0)
{
blockSize = useCompressedStringRebuilders ? TextModelOptions.CompressedStoragePageSize : TextImageLoader.BlockSize;
}
PageManager pageManager = null;
char[] buffer;
if (useCompressedStringRebuilders)
{
pageManager = new PageManager();
buffer = new char[blockSize];
}
else
{
buffer = TextImageLoader.AcquireBuffer(blockSize);
}
StringRebuilder content = StringRebuilderForChars.Empty;
try
{
bool nextCharIsStartOfLine = true;
while (true)
{
int read = TextImageLoader.LoadNextBlock(reader, buffer);
if (read == 0)
{
break;
}
var lineBreaks = TextImageLoader.ParseBlock(
buffer,
read,
thresholdForInvalidCharacters,
ref newlineState,
ref leadingWhitespaceState,
ref currentLineLength,
ref longestLineLength,
ref nextCharIsStartOfLine);
char[] bufferForStringBuilder = buffer;
if (read < (buffer.Length / 2))
{
// We read far less characters than buffer so copy the contents to a new buffer and reuse the original buffer.
bufferForStringBuilder = new char[read];
Array.Copy(buffer, bufferForStringBuilder, read);
}
else
{
// We're using most of buffer so allocate a new block for the next chunk.
buffer = new char[blockSize];
}
var newContent = (useCompressedStringRebuilders && (read > minCompressedBlockSize))
? StringRebuilderForCompressedChars.Create(new Page(pageManager, bufferForStringBuilder, read), lineBreaks)
: StringRebuilderForChars.Create(bufferForStringBuilder, read, lineBreaks);
content = content.Insert(content.Length, newContent);
}
longestLineLength = Math.Max(longestLineLength, currentLineLength);
}
finally
{
if (!useCompressedStringRebuilders)
{
TextImageLoader.ReleaseBuffer(buffer);
}
}
return(content);
}
// Evil performance hack (but we are on a hot path here):
// thresholdForInvalidCharacters should be '\u0001' if we are throwing on invalid characters.
// should be '\0' if we are not.
// (otherwise we need to check both a throwOnInvalidCharacters boolean and that c == 0).
private static ILineBreaks ParseBlock(char[] buffer, int length, char thresholdForInvalidCharacters,
ref NewlineState newlineState,
ref LeadingWhitespaceState leadingWhitespaceState,
ref int currentLineLength,
ref int longestLineLength,
ref bool nextCharIsStartOfLine)
{
// Note that the lineBreaks created here will (internally) use the pooled list of line breaks.
IPooledLineBreaksEditor lineBreaks = LineBreakManager.CreatePooledLineBreakEditor(length);
int index = 0;
while (index < length)
{
int breakLength = TextUtilities.LengthOfLineBreak(buffer, index, length);
if (breakLength == 0)
{
char c = buffer[index];
// If we are checking for invalid characters, throw if we encounter a \0
if (c < thresholdForInvalidCharacters)
{
throw new FileFormatException("File contains NUL characters");
}
++currentLineLength;
++index;
if (nextCharIsStartOfLine)
{
switch (c)
{
case ' ':
leadingWhitespaceState.Increment(LeadingWhitespaceState.LineLeadingCharacter.Space, 1);
break;
case '\t':
leadingWhitespaceState.Increment(LeadingWhitespaceState.LineLeadingCharacter.Tab, 1);
break;
default:
leadingWhitespaceState.Increment(LeadingWhitespaceState.LineLeadingCharacter.Printable, 1);
break;
}
nextCharIsStartOfLine = false;
}
}
else
{
lineBreaks.Add(index, breakLength);
longestLineLength = Math.Max(longestLineLength, currentLineLength);
currentLineLength = 0;
if (breakLength == 2)
{
newlineState.Increment(NewlineState.LineEnding.CRLF, 1);
}
else
{
switch (buffer[index])
{
// This code needs to be kep consistent with TextUtilities.LengthOfLineBreak()
case '\r': newlineState.Increment(NewlineState.LineEnding.CR, 1); break;
case '\n': newlineState.Increment(NewlineState.LineEnding.LF, 1); break;
case '\u0085': newlineState.Increment(NewlineState.LineEnding.NEL, 1); break;
case '\u2028': newlineState.Increment(NewlineState.LineEnding.LS, 1); break;
case '\u2029': newlineState.Increment(NewlineState.LineEnding.PS, 1); break;
default: throw new InvalidOperationException("Unexpected line ending");
}
}
if (nextCharIsStartOfLine)
{
leadingWhitespaceState.Increment(LeadingWhitespaceState.LineLeadingCharacter.Empty, 1);
}
nextCharIsStartOfLine = true;
}
index += breakLength;
}
lineBreaks.ReleasePooledLineBreaks();
return(lineBreaks);
}
