internal static char[]? EscapeString(
ReadOnlySpan <char> stringToEscape,
char[]?dest, ref int destPos,
bool checkExistingEscaped, char forceEscape1 = '\0', char forceEscape2 = '\0')
{
// Get the table of characters that do not need to be escaped.
ReadOnlySpan <bool> noEscape = stackalloc bool[0];
if ((forceEscape1 | forceEscape2) == 0)
{
noEscape = UnreservedReservedTable;
}
else
{
Span <bool> tmp = stackalloc bool[0x80];
UnreservedReservedTable.CopyTo(tmp);
tmp[forceEscape1] = false;
tmp[forceEscape2] = false;
noEscape = tmp;
}
// If the whole string is made up of ASCII unreserved chars, take a fast pasth. Per the contract, if
// dest is null, just return it. If it's not null, copy everything to it and update destPos accordingly;
// if that requires resizing it, do so.
Debug.Assert(!noEscape['%'], "Need to treat % specially in case checkExistingEscaped is true");
int i = 0;
char c;
for (; i < stringToEscape.Length && (c = stringToEscape[i]) <= 0x7F && noEscape[c]; i++)
{
;
}
if (i == stringToEscape.Length)
{
if (dest != null)
{
EnsureCapacity(dest, destPos, stringToEscape.Length);
stringToEscape.CopyTo(dest.AsSpan(destPos));
destPos += stringToEscape.Length;
}
return(dest);
}
// Otherwise, create a ValueStringBuilder to store the escaped data into,
// append to it all of the noEscape chars we already iterated through, and
// escape the rest into the ValueStringBuilder.
var vsb = new ValueStringBuilder(stackalloc char[256]);
vsb.Append(stringToEscape.Slice(0, i));
EscapeStringToBuilder(stringToEscape.Slice(i), ref vsb, noEscape, checkExistingEscaped);
// Finally update dest with the result.
EnsureCapacity(dest, destPos, vsb.Length);
vsb.TryCopyTo(dest.AsSpan(destPos), out int charsWritten);
destPos += charsWritten;
return(dest);
internal static unsafe void EscapeString(ReadOnlySpan <char> stringToEscape, ref ValueStringBuilder dest,
bool checkExistingEscaped, char forceEscape1 = '\0', char forceEscape2 = '\0')
{
// Get the table of characters that do not need to be escaped.
ReadOnlySpan <bool> noEscape = stackalloc bool[0];
if ((forceEscape1 | forceEscape2) == 0)
{
noEscape = UnreservedReservedTable;
}
else
{
Span <bool> tmp = stackalloc bool[0x80];
UnreservedReservedTable.CopyTo(tmp);
tmp[forceEscape1] = false;
tmp[forceEscape2] = false;
noEscape = tmp;
}
// If the whole string is made up of ASCII unreserved chars, take a fast pasth. Per the contract, if
// dest is null, just return it. If it's not null, copy everything to it and update destPos accordingly;
// if that requires resizing it, do so.
Debug.Assert(!noEscape['%'], "Need to treat % specially in case checkExistingEscaped is true");
int i = 0;
char c;
for (; i < stringToEscape.Length && (c = stringToEscape[i]) <= 0x7F && noEscape[c]; i++)
{
;
}
if (i == stringToEscape.Length)
{
dest.Append(stringToEscape);
}
else
{
dest.Append(stringToEscape.Slice(0, i));
// CS8350 & CS8352: We can't pass `noEscape` and `dest` as arguments together as that could leak the scope of the above stackalloc
// As a workaround, re-create the Span in a way that avoids analysis
ReadOnlySpan <bool> noEscapeCopy = MemoryMarshal.CreateReadOnlySpan(ref MemoryMarshal.GetReference(noEscape), noEscape.Length);
EscapeStringToBuilder(stringToEscape.Slice(i), ref dest, noEscapeCopy, checkExistingEscaped);
}
}