/// \brief Common function to setup function interface for a 16 bit "UCS2" input stream.
///
/// \param input Input stream context pointer
///
/// \remark
/// - Strictly speaking, there is no such thing as a UCS2 input stream as the term
/// tends to confuse the notions of character encoding, unicode and so on. However
/// because there will possibly be a need for a UTF-16 stream, I needed to identify 16 bit
/// streams that do not support surrogate encodings and UCS2 is how it is mostly referred to.
/// For instance Java, Oracle and others use a 16 bit encoding of characters and so this type
/// of stream is very common.
/// Take it to mean, therefore, a straight 16 bit uncomplicated encoding of Unicode code points.
///
void
antlr3UCS2SetupStream (pANTLR3_INPUT_STREAM input, ANTLR3_UINT32 type)
{
// Build a string factory for this stream. This is a 16 bit string "UCS2" factory which is a standard
// part of the ANTLR3 string. The string factory is then passed through the whole chain of lexer->parser->tree->treeparser
// and so on.
//
input->strFactory = antlr3UCS2StringFactoryNew();
// Install function pointers for an 8 bit ASCII input, which are good for almost
// all input stream functions. We will then override those that won't work for 16 bit characters.
//
antlr3GenericSetupStream (input, type);
// Intstream API overrides for UCS2
//
input->istream->consume = antlr3UCS2Consume; // Consume the next 16 bit character in the buffer
input->istream->_LA = antlr3UCS2LA; // Return the UTF32 character at offset n (1 based)
input->istream->index = antlr3UCS2Index; // Calculate current index in input stream, 16 bit based
input->istream->seek = antlr3UCS2Seek; // How to seek to a specific point in the stream
// Charstream API overrides for UCS2
//
input->substr = antlr3UCS2Substr; // Return a string from the input stream
input->charByteSize = 2; // Size in bytes of characters in this stream.
}
/// \brief Common function to setup function interface for an 8 bit ASCII input stream.
///
/// \param input Input stream context pointer
///
/// \remark
/// - Many of the 8 bit ASCII oriented file stream handling functions will be usable
/// by any or at least some other input streams. Therefore it is perfectly acceptable
/// to call this function to install the ASCII handler then override just those functions
/// that would not work for the particular input encoding, such as consume for instance.
///
void
antlr3AsciiSetupStream (pANTLR3_INPUT_STREAM input, ANTLR3_UINT32 type)
{
// Build a string factory for this stream
//
input->strFactory = antlr3StringFactoryNew();
// Default stream set up is for ASCII, therefore there is nothing else
// to do but set it up as such
//
antlr3GenericSetupStream(input, type);
}
static pANTLR3_INPUT_STREAM
antlr3CreateLineBufferedStream(std::istream& in)
{
// Pointer to the input stream we are going to create
//
pANTLR3_INPUT_STREAM input;
if (!in)
{
return NULL;
}
// Allocate memory for the input stream structure
//
input = (pANTLR3_INPUT_STREAM)
ANTLR3_CALLOC(1, sizeof(ANTLR3_LINE_BUFFERED_INPUT_STREAM));
if (input == NULL)
{
return NULL;
}
// Structure was allocated correctly, now we can install the pointer
//
input->data = malloc(1024);
input->isAllocated = ANTLR3_FALSE;
((pANTLR3_LINE_BUFFERED_INPUT_STREAM)input)->in = ∈
// Call the common 8 bit input stream handler
// initialization.
//
#ifdef CVC4_ANTLR3_OLD_INPUT_STREAM
antlr3AsciiSetupStream(input, ANTLR3_CHARSTREAM);
#else /* CVC4_ANTLR3_OLD_INPUT_STREAM */
antlr38BitSetupStream(input);
// In some libantlr3c 3.4-beta versions, this call is not included in the above.
// This is probably an erroneously-deleted line in the libantlr3c source since 3.2.
antlr3GenericSetupStream(input);
#endif /* CVC4_ANTLR3_OLD_INPUT_STREAM */
return input;
}