public void ReadTableRecord(MemoryStream ms)
{
_validationStatus = OTFile.OTFileValidation_PartialValidation;
if (ms.Length - ms.Position < TableRecordSize)
{
_validationStatus |= OTFile.OTFileValidation_StructureLengthOutOfRange;
}
try
{
_tableTag = OTTag.ReadTag(ms);
_checksum = OTFile.ReadUInt32(ms);
_tableOffset = OTFile.ReadUInt32(ms);
_tableLength = OTFile.ReadUInt32(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTRecordParseException("OT parse error: unable to read table record", e);
}
} // ReadTableRecord
public static UInt32 CalcTableCheckSum(MemoryStream ms, UInt32 offset, UInt32 length, UInt32 leftPriorSum)
{
// C# addition is left associative, not left-and-right. To combine checksums
// computed on separate adjacent portions of memory, following UInt32s must
// be added to the prior sum as the right operand: priorSum + nextVal, not
// nextVal + priorSum. The leftPriorSum parameter is a starting left-operand
// value.
ms.Seek(offset, SeekOrigin.Begin);
UInt32 sum = leftPriorSum;
// greedy: length is expected to be multiple of 4 with 0 padding
UInt32 count = ((length + 3U) & ~3U) / sizeof(UInt32);
for (int i = 0; i < count; i++)
{
unchecked // allow overflow
{
sum += OTFile.ReadUInt32(ms);
}
}
return(sum);
}
protected override void ReadTable_Internal()
{
// Base class constructor ran partial validations on the table record,
// including checking that the offset and length are within bounds
if ((_validationStatus & OTFile.OTFileValidation_StructureOffsetOutOfRange) != 0)
{
// out of range so can't read anything
return;
}
MemoryStream ms = _parentFont.MemoryStream;
// Read header fields
// Table has 16-bit (minor) version field, so any version has known fields
if (_tableRecord.Length < _colr_0_headerLength)
_validationStatus |= OTFile.OTFileValidation_TableLengthTooShort;
try
{
ms.Seek(_tableRecord.Offset, SeekOrigin.Begin);
_version = OTFile.ReadUInt16(ms);
_numBaseGlyphRecords = OTFile.ReadUInt16(ms);
_baseGlyphRecordsOffset = OTFile.ReadUInt32(ms);
_layerRecordsOffset = OTFile.ReadUInt32(ms);
_numLayerRecords = OTFile.ReadUInt16(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTDataIncompleteReadException("OT parse error: unable to read " + _tableTag + " table", e);
}
if (_version > _latestKnownMinorVersion)
_validationStatus |= OTFile.OTFileValidation_StructureMinorVersionUnknown;
// check length then read base glyph records
uint requiredLength = _baseGlyphRecordsOffset + _numBaseGlyphRecords * _baseGlyphRecordLength;
if (_tableRecord.Length < requiredLength)
_validationStatus |= OTFile.OTFileValidation_TableLengthTooShort;
try
{
ms.Seek(_tableRecord.Offset + _baseGlyphRecordsOffset, SeekOrigin.Begin);
_baseGlyphRecords = new BaseGlyphRecord[_numBaseGlyphRecords];
for (uint i = 0; i < _numBaseGlyphRecords; i++)
{
_baseGlyphRecords[i].ReadBaseGlyphRecord(ms);
}
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTDataIncompleteReadException("OT parse error: unable to read " + _tableTag + " table", e);
}
// check length then read layer records
requiredLength = _layerRecordsOffset + _numLayerRecords * _layerRecordLength;
if (_tableRecord.Length < requiredLength)
_validationStatus |= OTFile.OTFileValidation_TableLengthTooShort;
try
{
ms.Seek(_tableRecord.Offset + _layerRecordsOffset, SeekOrigin.Begin);
_layerRecords = new LayerRecord[_numLayerRecords];
for (uint i = 0; i < _numLayerRecords; i++)
{
_layerRecords[i].ReadLayerRecord(ms);
}
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTDataIncompleteReadException("OT parse error: unable to read " + _tableTag + " table", e);
}
}
} // Validate
#endregion
#region Private instance methods
protected override void ReadTable_Internal()
{
// Base class constructor ran partial validations on the table record,
// including checking that the offset and length are within bounds
if ((_validationStatus & OTFile.OTFileValidation_StructureOffsetOutOfRange) != 0)
{
// out of range so can't read anything
return;
}
MemoryStream ms = _parentFont.MemoryStream;
// Get the version and check that before continuing
try
{
ms.Seek(_tableRecord.Offset, SeekOrigin.Begin);
_version = OTFixed.ReadFixed(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTFileParseException("OT parse error: unable to read " + _tableTag + " table", e);
}
if (_version.Mantissa != 2)
{
_validationStatus |= OTFile.OTFileValidation_StructureVersionNotSupported;
throw new OTUnknownVersionException("OT parse error: unrecognized " + _tableTag + " version");
}
if (_version.FixedTableMinorVersionToInteger() > _fmtx_2_latestKnownMinorVersion)
{
_validationStatus |= OTFile.OTFileValidation_StructureMinorVersionUnknown;
}
if (_tableRecord.Length < _fmtx_2_0_headerLength)
{
_validationStatus |= OTFile.OTFileValidation_TableLengthTooShort;
}
// Known version, OK to continue
try
{
_glyphIndex = OTFile.ReadUInt32(ms);
_horizontalBefore = OTFile.ReadUInt8(ms);
_horizontalAfter = OTFile.ReadUInt8(ms);
_horizontalCaretHead = OTFile.ReadUInt8(ms);
_horizontalCaretBase = OTFile.ReadUInt8(ms);
_verticalBefore = OTFile.ReadUInt8(ms);
_verticalAfter = OTFile.ReadUInt8(ms);
_verticalCaretHead = OTFile.ReadUInt8(ms);
_verticalCaretBase = OTFile.ReadUInt8(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTFileParseException("OT parse error: unable to read " + _tableTag + " table", e);
}
} // ReadTable_Internal
public void ReadTtcHeader(MemoryStream ms)
{
// Makes sure we're at the start of the file.
ms.Seek(0, SeekOrigin.Begin);
_fileOffset = 0;
_validationStatus = OTFile.OTFileValidation_PartialValidation;
if (ms.Length < (4 + 2 * sizeof(UInt16)))
{
_validationStatus |= OTFile.OTFileValidation_TtcHeaderLengthOutOfRange | OTFile.OTFileValidation_StructureLengthOutOfRange;
}
try
{
_tag = new byte[4];
if (ms.Read(_tag) < 4)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTDataIncompleteReadException("OT parse error: unable to read sufficient bytes to TTC header tag");
}
_majorVersion = OTFile.ReadUInt16(ms);
_minorVersion = OTFile.ReadUInt16(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTFileParseException("OT parse error: unable to read TTC header", e);
}
if (_majorVersion != 1 && _majorVersion != 2)
{
_validationStatus |= OTFile.OTFileValidation_StructureVersionNotSupported;
throw new OTUnknownVersionException("OT parse error: unrecognized TTC header version");
}
if (ms.Length < (4 + 2 * sizeof(UInt16) + sizeof(UInt32)))
{
_validationStatus |= OTFile.OTFileValidation_TtcHeaderLengthOutOfRange | OTFile.OTFileValidation_StructureLengthOutOfRange;
}
try
{
_numFonts = OTFile.ReadUInt32(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTFileParseException("OT parse error: unable to read TTC header", e);
}
if (ms.Length < (4 + 2 * sizeof(UInt16) + (_numFonts + 1) * sizeof(UInt32)))
{
_validationStatus |= OTFile.OTFileValidation_TtcHeaderLengthOutOfRange | OTFile.OTFileValidation_StructureLengthOutOfRange;
}
_offsetTableOffsets = new uint[_numFonts];
for (UInt32 i = 0; i < _numFonts; i++)
{
try
{
_offsetTableOffsets[i] = OTFile.ReadUInt32(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTFileParseException("OT parse error: unable to read TTC header", e);
}
} // loop over offsets array
if (_majorVersion == 2)
{
// may have DSIG table
if (ms.Length < (4 + 2 * sizeof(UInt16) + (_numFonts + 4) * sizeof(UInt32)))
{
_validationStatus |= OTFile.OTFileValidation_TtcHeaderLengthOutOfRange | OTFile.OTFileValidation_StructureLengthOutOfRange;
}
try
{
_dsigTag = new byte[4];
if (ms.Read(_dsigTag) < 4)
{
throw new OTDataIncompleteReadException("OT parse error: unable to read sufficient bytes to DSIG tag");
}
_dsigLength = OTFile.ReadUInt32(ms);
_dsigOffset = OTFile.ReadUInt32(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTFileParseException("OT parse error: unable to read TTC header", e);
}
} // version 2.x
} // ReadTtcHeader
} // Validate
#endregion
#region Private instance methods
protected override void ReadTable_Internal()
{
// Base class constructor ran partial validations on the table record,
// including checking that the offset and length are within bounds
if ((_validationStatus & OTFile.OTFileValidation_StructureOffsetOutOfRange) != 0)
{
// out of range so can't read anything
return;
}
MemoryStream ms = _parentFont.MemoryStream;
// Get the version and check that before continuing
try
{
ms.Seek(_tableRecord.Offset, SeekOrigin.Begin);
_majorVersion = OTFile.ReadUInt16(ms);
_minorVersion = OTFile.ReadUInt16(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTFileParseException("OT parse error: unable to read " + _tableTag + " table", e);
}
if (_majorVersion != 1)
{
_validationStatus |= OTFile.OTFileValidation_StructureVersionNotSupported;
throw new OTUnknownVersionException("OT parse error: unrecognized " + _tableTag + " version");
}
if (_minorVersion > _head_1_latestKnownMinorVersion)
{
_validationStatus |= OTFile.OTFileValidation_StructureMinorVersionUnknown;
}
if (_tableRecord.Length < _head_1_0_headerLength)
{
_validationStatus |= OTFile.OTFileValidation_TableLengthTooShort;
}
// Known version, OK to continue
try
{
_fontRevision = OTFixed.ReadFixed(ms);
_checkSumAdjustment = OTFile.ReadUInt32(ms);
_magicNumber = OTFile.ReadUInt32(ms);
_flagsRaw = OTFile.ReadUInt16(ms);
_unitsPerEm = OTFile.ReadUInt16(ms);
_createdRaw = OTFile.ReadOTLongDateTimeAsInt64(ms);
_modifiedRaw = OTFile.ReadOTLongDateTimeAsInt64(ms);
_xMin = OTFile.ReadInt16(ms);
_yMin = OTFile.ReadInt16(ms);
_xMax = OTFile.ReadInt16(ms);
_yMax = OTFile.ReadInt16(ms);
_macStyleRaw = OTFile.ReadUInt16(ms);
_lowestRecPPEm = OTFile.ReadUInt16(ms);
_fontDirectionHint = OTFile.ReadInt16(ms);
_indexToLocFormat = OTFile.ReadInt16(ms);
_glyphDataFormat = OTFile.ReadInt16(ms);
}
catch (OTDataIncompleteReadException e)
{
_validationStatus |= OTFile.OTFileValidation_ReadTrunctated;
throw new OTFileParseException("OT parse error: unable to read " + _tableTag + " table", e);
}
SetHeadFlagValues(); // set HeadFlags struct values
SetHeadMacStyleValues(); // set HeadMacStyle struct values
} // ReadTable_Internal