void
SmallMem::free(void* addr) {
if (addr == nullptr) {
return;
}
ptrdiff_t offset = char_ptr(addr) - sizeof(mem_info) - char_ptr(reserved_mem);
mem_info* info = get_mem_info(addr);
ptrdiff_t end = (char_ptr(addr) + info->size) - char_ptr(reserved_mem);
for (ptrdiff_t i = offset; i < end; i++) {
clear_bit(i);
}
}
/// return a code point (max 16 bits?) and the len in code units of the character at pos
wchar_t char_at(const ::std::string& text_utf8, unsigned pos, unsigned * len)
{
const char* ptr;
if (pos)
{
ptr = char_ptr(text_utf8, pos);
if (!ptr)
return 0;
}
else
ptr = text_utf8.c_str();
const wchar_t uch = *reinterpret_cast<const unsigned char*>(ptr);
if (uch < 0x80)
{
if (len)
*len = 1;
return *ptr;
}
if (uch < 0xC0)
{
if (len)
*len = 0;
return 0;
}
const auto end = text_utf8.c_str() + text_utf8.size();
if (uch < 0xE0 && (ptr + 1 <= end))
{
if (len)
*len = 2;
return (wchar_t(uch & 0x1F) << 6) | (reinterpret_cast<const unsigned char*>(ptr)[1] & 0x3F);
}
else if (uch < 0xF0 && (ptr + 2 <= end))
{
if (len)
*len = 3;
return ((((uch & 0xF) << 6) | (reinterpret_cast<const unsigned char*>(ptr)[1] & 0x3F)) << 6) | (reinterpret_cast<const unsigned char*>(ptr)[2] & 0x3F);
}
else if (uch < 0x1F && (ptr + 3 <= end))
{
if (len)
*len = 4;
return ((((((uch & 0x7) << 6) | (reinterpret_cast<const unsigned char*>(ptr)[1] & 0x3F)) << 6) | (reinterpret_cast<const unsigned char*>(ptr)[2] & 0x3F)) << 6) | (reinterpret_cast<const unsigned char*>(ptr)[3] & 0x3F);
}
if (len)
*len = 0;
return 0;
}
/// return a code point (max 16 bits?) and the len in code units of the character at pos
wchar_t char_at(const char* text_utf8, unsigned pos, unsigned * len)
{
if (!text_utf8)
return 0;
if (pos)
{
text_utf8 = char_ptr(text_utf8, pos);
if (!text_utf8)
return 0;
}
const wchar_t uch = *reinterpret_cast<const unsigned char*>(text_utf8);
if (uch < 0x80)
{
if (len)
*len = 1;
return *text_utf8; // uch ?
}
if (uch < 0xC0) // use police or ??
{
if (len)
*len = 0;
return 0;
}
const auto end = text_utf8 + std::strlen(text_utf8);
if (uch < 0xE0 && (text_utf8 + 1 <= end))
{
if (len)
*len = 2;
return (wchar_t(uch & 0x1F) << 6) | (reinterpret_cast<const unsigned char*>(text_utf8)[1] & 0x3F);
}
else if (uch < 0xF0 && (text_utf8 + 2 <= end))
{
if (len)
*len = 3;
return ((((uch & 0xF) << 6) | (reinterpret_cast<const unsigned char*>(text_utf8)[1] & 0x3F)) << 6) | (reinterpret_cast<const unsigned char*>(text_utf8)[2] & 0x3F);
}
else if (uch < 0x1F && (text_utf8 + 3 <= end))
{
if (len)
*len = 4;
return ((((((uch & 0x7) << 6) | (reinterpret_cast<const unsigned char*>(text_utf8)[1] & 0x3F)) << 6) | (reinterpret_cast<const unsigned char*>(text_utf8)[2] & 0x3F)) << 6) | (reinterpret_cast<const unsigned char*>(text_utf8)[3] & 0x3F);
}
if (len)
*len = 0;
return 0;
}
constexpr bigmem_info* get_mem_info(void* ptr) { return reinterpret_cast<bigmem_info*>(char_ptr(ptr) - sizeof(bigmem_info)); }
constexpr mem_info* get_mem_info(T* ptr) { return reinterpret_cast<mem_info*>(char_ptr(ptr) - sizeof(mem_info)); }
