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/*
* MRustC - Mutabah's Rust Compiler
* - By John Hodge (Mutabah/thePowersGang)
*
* rc_string.cpp
* - Reference-counted string
*/
#include <rc_string.hpp>
#include <cstring>
#include <string>
#include <iostream>
#include <algorithm> // std::max
RcString::RcString(const char* s, unsigned int len):
m_ptr(nullptr)
{
if( len > 0 )
{
m_ptr = new unsigned int[2 + (len+1 + sizeof(unsigned int)-1) / sizeof(unsigned int)];
m_ptr[0] = 1;
m_ptr[1] = len;
char* data_mut = reinterpret_cast<char*>(m_ptr + 2);
for(unsigned int j = 0; j < len; j ++ )
data_mut[j] = s[j];
data_mut[len] = '\0';
//::std::cout << "RcString(" << m_ptr << " \"" << *this << "\") - " << *m_ptr << " (creation)" << ::std::endl;
}
}
RcString::~RcString()
{
if(m_ptr)
{
*m_ptr -= 1;
//::std::cout << "RcString(" << m_ptr << " \"" << *this << "\") - " << *m_ptr << " refs left (drop)" << ::std::endl;
if( *m_ptr == 0 )
{
delete[] m_ptr;
m_ptr = nullptr;
}
}
}
Ordering RcString::ord(const char* s, size_t len) const
{
if( m_ptr == nullptr )
return (len == 0 ? OrdEqual : OrdLess);
if( len == 0 )
return OrdGreater;
assert(this->size() > 0);
assert(len > 0);
int cmp = memcmp(this->c_str(), s, ::std::min(len, this->size()));
if(cmp == 0)
return ::ord(this->size(), len);
return ::ord(cmp, 0);
}
Ordering RcString::ord(const char* s) const
{
if( m_ptr == nullptr )
return (*s == '\0' ? OrdEqual : OrdLess);
int cmp = strncmp(this->c_str(), s, this->size());
if( cmp == 0 )
{
if( s[this->size()] == '\0' )
return OrdEqual;
else
return OrdLess;
}
return ::ord(cmp, 0);
}
::std::ostream& operator<<(::std::ostream& os, const RcString& x)
{
for(size_t i = 0; i < x.size(); i ++)
{
os << x.c_str()[i];
}
return os;
}
::std::set<RcString> RcString_interned_strings;
RcString RcString::new_interned(const ::std::string& s)
{
#if 0
auto it = RcString_interned_strings.find(s);
if( it == RcString_interned_strings.end() )
{
it = RcString_interned_strings.insert(RcString(s)).first;
}
return *it;
#else
// TODO: interning flag, so comparisons can just be a pointer comparison
// - Only want to set this flag on the cached instance
return *RcString_interned_strings.insert(RcString(s)).first;
#endif
}
RcString RcString::new_interned(const char* s)
{
#if 0
auto it = RcString_interned_strings.find(s);
if( it == RcString_interned_strings.end() )
{
it = RcString_interned_strings.insert(RcString(s)).first;
}
return *it;
#else
// TODO: interning flag, so comparisons can just be a pointer comparison
// - Only want to set this flag on the cached instance
return *RcString_interned_strings.insert(RcString(s)).first;
#endif
}
size_t std::hash<RcString>::operator()(const RcString& s) const noexcept
{
// http://www.cse.yorku.ca/~oz/hash.html "djb2"
size_t h = 5381;
for(auto c : s) {
h = h * 33 + (unsigned)c;
}
return h;
//return hash<std::string_view>(s.c_str(), s.size());
}
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