string m_printf_buffer; //ovectorstream m_printf_buffer; // persistent buffer for formatted output
protected core_text_file(uint32_t openflags)
{
m_openflags = openflags;
m_text_type = text_file_type.OSD;
m_back_char_head = 0;
m_back_char_tail = 0;
m_printf_buffer = "";
}
/*-------------------------------------------------
* getc - read a character from a file
* -------------------------------------------------*/
public override int getc()
{
// refresh buffer, if necessary
if (m_back_char_head == m_back_char_tail)
{
// do we need to check the byte order marks?
uint64_t pos;
if (!tell(out pos))
{
if (pos == 0)
{
size_t readlen;
MemoryU8 bom = new MemoryU8(4, true); //std::uint8_t bom[4];
read(new PointerU8(bom), 4, out readlen);
if (readlen == 4)
{
if (bom[0] == 0xef && bom[1] == 0xbb && bom[2] == 0xbf)
{
m_text_type = text_file_type.UTF8;
pos = 3;
}
else if (bom[0] == 0x00 && bom[1] == 0x00 && bom[2] == 0xfe && bom[3] == 0xff)
{
m_text_type = text_file_type.UTF32BE;
pos = 4;
}
else if (bom[0] == 0xff && bom[1] == 0xfe && bom[2] == 0x00 && bom[3] == 0x00)
{
m_text_type = text_file_type.UTF32LE;
pos = 4;
}
else if (bom[0] == 0xfe && bom[1] == 0xff)
{
m_text_type = text_file_type.UTF16BE;
pos = 2;
}
else if (bom[0] == 0xff && bom[1] == 0xfe)
{
m_text_type = text_file_type.UTF16LE;
pos = 2;
}
else
{
m_text_type = text_file_type.OSD;
pos = 0;
}
}
seek((int64_t)pos, SEEK_SET); // FIXME: don't assume seeking is possible, check for errors
}
}
// fetch the next character
// FIXME: all of this plays fast and loose with error checking and seeks backwards far too frequently
MemoryU8 utf16_buffer = new MemoryU8(UTF16_CHAR_MAX, true); //char16_t utf16_buffer[UTF16_CHAR_MAX];
var uchar = char32_t.MaxValue; //auto uchar = char32_t(~0);
switch (m_text_type)
{
default:
case text_file_type.OSD:
{
MemoryU8 default_buffer = new MemoryU8(16, true); //char default_buffer[16];
size_t readlen;
read(new PointerU8(default_buffer), (size_t)default_buffer.Count, out readlen); //read(default_buffer, sizeof(default_buffer), readlen);
if (readlen > 0)
{
//auto const charlen = osd_uchar_from_osdchar(&uchar, default_buffer, readlen / sizeof(default_buffer[0]));
uchar = default_buffer[0];
var charlen = 1;
seek((int64_t)(charlen * 1) - (int64_t)readlen, SEEK_CUR); //seek(std::int64_t(charlen * sizeof(default_buffer[0])) - readlen, SEEK_CUR);
}
}
break;
case text_file_type.UTF8:
{
MemoryU8 utf8_buffer = new MemoryU8(UTF8_CHAR_MAX, true); //char utf8_buffer[UTF8_CHAR_MAX];
size_t readlen;
read(new PointerU8(utf8_buffer), (size_t)utf8_buffer.Count, out readlen);
if (readlen > 0)
{
//auto const charlen = uchar_from_utf8(&uchar, utf8_buffer, readlen / sizeof(utf8_buffer[0]));
uchar = utf8_buffer[0];
var charlen = 1;
seek((int64_t)(charlen * 1) - (int64_t)readlen, SEEK_CUR); //seek(std::int64_t(charlen * sizeof(utf8_buffer[0])) - readlen, SEEK_CUR);
}
}
break;
case text_file_type.UTF16BE:
{
size_t readlen;
read(new PointerU8(utf16_buffer), (size_t)utf16_buffer.Count, out readlen); //read(utf16_buffer, sizeof(utf16_buffer), readlen);
if (readlen > 0)
{
throw new emu_unimplemented();
}
}
break;
case text_file_type.UTF16LE:
{
size_t readlen;
read(new PointerU8(utf16_buffer), (size_t)utf16_buffer.Count, out readlen); //read(utf16_buffer, sizeof(utf16_buffer), readlen);
if (readlen > 0)
{
throw new emu_unimplemented();
}
}
break;
case text_file_type.UTF32BE:
{
// FIXME: deal with read returning short
size_t readlen;
MemoryU8 ucharTemp = new MemoryU8(4, true);
read(new PointerU8(ucharTemp), 4, out readlen); //read(&uchar, sizeof(uchar), readlen);
if (4 == readlen) //if (sizeof(uchar) == readlen)
{
throw new emu_unimplemented();
}
}
break;
case text_file_type.UTF32LE:
{
// FIXME: deal with read returning short
size_t readlen;
MemoryU8 ucharTemp = new MemoryU8(4, true);
read(new PointerU8(ucharTemp), 4, out readlen); //read(&uchar, sizeof(uchar), readlen);
if (4 == readlen) //if (sizeof(uchar) == readlen)
{
uchar = little_endianize_int32(ucharTemp.GetUInt32());
}
}
break;
}
if (uchar != char32_t.MaxValue) //if (uchar != ~0)
{
// place the new character in the ring buffer
m_back_char_head = 0;
m_back_char_tail = utf8_from_uchar(out string back_chars, uchar); //m_back_char_tail = utf8_from_uchar(m_back_chars, std::size(m_back_chars), uchar);
back_chars.CopyTo(0, m_back_chars, 0, back_chars.Length);
//assert(file->back_char_tail != -1);
}
}
// now read from the ring buffer
int result;
if (m_back_char_head == m_back_char_tail)
{
result = EOF;
}
else
{
result = m_back_chars[m_back_char_head++];
m_back_char_head %= (int)std.size(m_back_chars);
}
return(result);
}
