public MetadataBuilder(
int userStringHeapStartOffset = 0,
int stringHeapStartOffset = 0,
int blobHeapStartOffset = 0,
int guidHeapStartOffset = 0)
{
// -1 for the 0 we always write at the beginning of the heap:
if (userStringHeapStartOffset >= UserStringHeapSizeLimit - 1)
{
throw ImageFormatLimitationException.HeapSizeLimitExceeded(HeapIndex.UserString);
}
// Add zero-th entry to all heaps, even in EnC delta.
// We don't want generation-relative handles to ever be IsNil.
// In both full and delta metadata all nil heap handles should have zero value.
// There should be no blob handle that references the 0 byte added at the
// beginning of the delta blob.
_userStringBuilder.WriteByte(0);
_blobs.Add(ImmutableArray <byte> .Empty, default(BlobHandle));
_blobHeapSize = 1;
// When EnC delta is applied #US, #String and #Blob heaps are appended.
// Thus indices of strings and blobs added to this generation are offset
// by the sum of respective heap sizes of all previous generations.
_userStringHeapStartOffset = userStringHeapStartOffset;
_stringHeapStartOffset = stringHeapStartOffset;
_blobHeapStartOffset = blobHeapStartOffset;
// Unlike other heaps, #Guid heap in EnC delta is zero-padded.
_guidBuilder.WriteBytes(0, guidHeapStartOffset);
}
private int GetNewUserStringHeapOffset(int stringLength)
{
int startPosition = _userStringWriter.Position;
int offset = startPosition + _userStringHeapStartOffset;
// Native metadata emitter allows strings to exceed the heap size limit as long
// as the index is within the limits (see https://github.com/dotnet/roslyn/issues/9852)
if (offset > UserStringHeapSizeLimit)
{
ImageFormatLimitationException.ThrowHeapSizeLimitExceeded(HeapIndex.UserString);
}
return(offset);
}
/// <exception cref="ImageFormatLimitationException">The remaining space on the heap is too small to fit the string.</exception>
public UserStringHandle GetOrAddUserString(string str)
{
int index;
if (!_userStrings.TryGetValue(str, out index))
{
Debug.Assert(!_streamsAreComplete);
int startPosition = _userStringBuilder.Count;
int encodedLength = str.Length * 2 + 1;
index = startPosition + _userStringHeapStartOffset;
// Native metadata emitter allows strings to exceed the heap size limit as long
// as the index is within the limits (see https://github.com/dotnet/roslyn/issues/9852)
if (index >= UserStringHeapSizeLimit)
{
throw ImageFormatLimitationException.HeapSizeLimitExceeded(HeapIndex.UserString);
}
_userStrings.Add(str, index);
_userStringBuilder.WriteCompressedInteger(encodedLength);
_userStringBuilder.WriteUTF16(str);
// Write out a trailing byte indicating if the string is really quite simple
byte stringKind = 0;
foreach (char ch in str)
{
if (ch >= 0x7F)
{
stringKind = 1;
}
else
{
switch ((int)ch)
{
case 0x1:
case 0x2:
case 0x3:
case 0x4:
case 0x5:
case 0x6:
case 0x7:
case 0x8:
case 0xE:
case 0xF:
case 0x10:
case 0x11:
case 0x12:
case 0x13:
case 0x14:
case 0x15:
case 0x16:
case 0x17:
case 0x18:
case 0x19:
case 0x1A:
case 0x1B:
case 0x1C:
case 0x1D:
case 0x1E:
case 0x1F:
case 0x27:
case 0x2D:
stringKind = 1;
break;
default:
continue;
}
}
break;
}
_userStringBuilder.WriteByte(stringKind);
}
return(MetadataTokens.UserStringHandle(index));
}
