/// <summary>
/// Client to acquire a state at the point where line is broken by line breaking process;
/// can be null when the line ends by the ending of the paragraph. Client may pass this
/// value back to TextFormatter as an input argument to TextFormatter.FormatLine when
/// formatting the next line within the same paragraph.
/// </summary>
/// <remarks>
/// TextLineBreak is a finalizable object which may contain a reference to an unmanaged
/// structure called break record. Break record can be acquired thru ploline. This method
/// acquire break record only when the passing ploline object is not NULL.
///
/// Not all situations requires break record. Single-line formatting without complex text
/// object does not need it, but optimal break session does. For performance reason, we
/// should not produce break record unnecessarily because it makes TextLineBreak become
/// finalizable, which therefore unnecessarily put additional pressure to GC since each
/// finalizable object wakes finalizer thread and requires double GC collections.
/// </remarks>
internal TextLineBreak GetTextLineBreak(IntPtr ploline)
{
IntPtr pbreakrec = IntPtr.Zero;
if (ploline != IntPtr.Zero)
{
LsErr lserr = UnsafeNativeMethods.LoAcquireBreakRecord(ploline, out pbreakrec);
if (lserr != LsErr.None)
{
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.AcquireBreakRecordFailure, lserr), lserr);
}
}
if (_lastRun != null &&
_lastRun.TextModifierScope != null &&
!(_lastRun.TextRun is TextEndOfParagraph))
{
return(new TextLineBreak(
_lastRun.TextModifierScope,
new SecurityCriticalDataForSet <IntPtr>(pbreakrec)
));
}
return((pbreakrec != IntPtr.Zero) ? new TextLineBreak(null, new SecurityCriticalDataForSet <IntPtr>(pbreakrec)) : null);
}
private bool _penalizedAsJustified; // flag indicating whether the paragraph should be penalized as fully-justified one
/// <summary>
/// Construct a paragraph cache to be used during optimal paragraph formatting
/// </summary>
internal TextParagraphCache(
FormatSettings settings,
int firstCharIndex,
int paragraphWidth
)
{
Invariant.Assert(settings != null);
// create full text
_finiteFormatWidth = settings.GetFiniteFormatWidth(paragraphWidth);
_fullText = FullTextState.Create(settings, firstCharIndex, _finiteFormatWidth);
// acquiring LS context
TextFormatterContext context = settings.Formatter.AcquireContext(_fullText, IntPtr.Zero);
_fullText.SetTabs(context);
IntPtr ploparabreakValue = IntPtr.Zero;
LsErr lserr = context.CreateParaBreakingSession(
firstCharIndex,
_finiteFormatWidth,
// breakrec is not needed before the first cp of para cache
// since we handle Bidi break ourselves.
IntPtr.Zero,
ref ploparabreakValue,
ref _penalizedAsJustified
);
// get the exception in context before it is released
Exception callbackException = context.CallbackException;
// release the context
context.Release();
if (lserr != LsErr.None)
{
GC.SuppressFinalize(this);
if (callbackException != null)
{
// rethrow exception thrown in callbacks
throw new InvalidOperationException(SR.Get(SRID.CreateParaBreakingSessionFailure, lserr), callbackException);
}
else
{
// throw with LS error codes
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.CreateParaBreakingSessionFailure, lserr), lserr);
}
}
_ploparabreak.Value = ploparabreakValue;
// keep context alive till here
GC.KeepAlive(context);
}
internal TextPenaltyModule(SecurityCriticalDataForSet <IntPtr> ploc)
{
IntPtr ploPenaltyModule;
LsErr lserr = UnsafeNativeMethods.LoAcquirePenaltyModule(ploc.Value, out ploPenaltyModule);
if (lserr != LsErr.None)
{
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.AcquirePenaltyModuleFailure, lserr), lserr);
}
_ploPenaltyModule.Value = ploPenaltyModule;
}
internal override SecurityCriticalDataForSet <IntPtr> GetTextPenaltyResource()
{
if (_isDisposed)
{
throw new ObjectDisposedException(SR.Get(SRID.TextBreakpointHasBeenDisposed));
}
LsErr lserr = UnsafeNativeMethods.LoRelievePenaltyResource(_ploline.Value);
if (lserr != LsErr.None)
{
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.RelievePenaltyResourceFailure, lserr), lserr);
}
return(_penaltyResource);
}
public TextLineBreak Clone()
{
IntPtr pbreakrec = IntPtr.Zero;
if (_breakRecord.Value != IntPtr.Zero)
{
LsErr lserr = UnsafeNativeMethods.LoCloneBreakRecord(_breakRecord.Value, out pbreakrec);
if (lserr != LsErr.None)
{
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.CloneBreakRecordFailure, lserr), lserr);
}
}
return(new TextLineBreak(_currentScope, new SecurityCriticalDataForSet <IntPtr>(pbreakrec)));
}
internal IntPtr DangerousGetHandle()
{
if (_isDisposed)
{
throw new ObjectDisposedException(SR.Get(SRID.TextPenaltyModuleHasBeenDisposed));
}
IntPtr penaltyModuleInternalHandle;
LsErr lserr = UnsafeNativeMethods.LoGetPenaltyModuleInternalHandle(_ploPenaltyModule.Value, out penaltyModuleInternalHandle);
if (lserr != LsErr.None)
{
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.GetPenaltyModuleHandleFailure, lserr), lserr);
}
GC.KeepAlive(this);
return(penaltyModuleInternalHandle);
}
internal static IList <TextBreakpoint> CreateMultiple(
TextParagraphCache paragraphCache,
int firstCharIndex,
int maxLineWidth,
TextLineBreak previousLineBreak,
IntPtr penaltyRestriction,
out int bestFitIndex
)
{
Invariant.Assert(paragraphCache != null);
// grab full text state from paragraph cache
FullTextState fullText = paragraphCache.FullText;
Invariant.Assert(fullText != null);
FormatSettings settings = fullText.TextStore.Settings;
Invariant.Assert(settings != null);
// update formatting parameters at line start
settings.UpdateSettingsForCurrentLine(
maxLineWidth,
previousLineBreak,
(firstCharIndex == fullText.TextStore.CpFirst)
);
Invariant.Assert(settings.Formatter != null);
// acquiring LS context
TextFormatterContext context = settings.Formatter.AcquireContext(fullText, IntPtr.Zero);
IntPtr previousBreakRecord = IntPtr.Zero;
if (settings.PreviousLineBreak != null)
{
previousBreakRecord = settings.PreviousLineBreak.BreakRecord.Value;
}
// need not consider marker as tab since marker does not affect line metrics and it wasnt drawn.
fullText.SetTabs(context);
LsBreaks lsbreaks = new LsBreaks();
LsErr lserr = context.CreateBreaks(
fullText.GetBreakpointInternalCp(firstCharIndex),
previousBreakRecord,
paragraphCache.Ploparabreak.Value, // para breaking session
penaltyRestriction,
ref lsbreaks,
out bestFitIndex
);
// get the exception in context before it is released
Exception callbackException = context.CallbackException;
// release the context
context.Release();
if (lserr != LsErr.None)
{
if (callbackException != null)
{
// rethrow exception thrown in callbacks
throw callbackException;
}
else
{
// throw with LS error codes
TextFormatterContext.ThrowExceptionFromLsError(SR.Get(SRID.CreateBreaksFailure, lserr), lserr);
}
}
// keep context alive at least till here
GC.KeepAlive(context);
TextBreakpoint[] breakpoints = new TextBreakpoint[lsbreaks.cBreaks];
for (int i = 0; i < lsbreaks.cBreaks; i++)
{
breakpoints[i] = new FullTextBreakpoint(
fullText,
firstCharIndex,
maxLineWidth,
ref lsbreaks,
i // the current break
);
}
return(breakpoints);
}