home/src/shared_string.hh
2016-02-05 09:38:33 +00:00

78 lines
1.9 KiB
C++

#ifndef shared_string_hh_INCLUDED
#define shared_string_hh_INCLUDED
#include "string.hh"
#include "ref_ptr.hh"
#include "utils.hh"
#include "unordered_map.hh"
namespace Kakoune
{
struct StringData : UseMemoryDomain<MemoryDomain::SharedString>
{
int refcount;
int length;
uint32_t hash;
StringData(int ref, int len) : refcount(ref), length(len) {}
[[gnu::always_inline]]
char* data() { return reinterpret_cast<char*>(this + 1); }
[[gnu::always_inline]]
const char* data() const { return reinterpret_cast<const char*>(this + 1); }
[[gnu::always_inline]]
StringView strview() const { return {data(), length}; }
static RefPtr<StringData> create(StringView str, char back = 0)
{
const int len = (int)str.length() + (back != 0 ? 1 : 0);
void* ptr = StringData::operator new(sizeof(StringData) + len + 1);
StringData* res = new (ptr) StringData(0, len);
std::copy(str.begin(), str.end(), res->data());
if (back != 0)
res->data()[len-1] = back;
res->data()[len] = 0;
res->hash = hash_data(res->data(), res->length);
return RefPtr<StringData>(res);
}
static void destroy(StringData* s)
{
StringData::operator delete(s, sizeof(StringData) + s->length + 1);
}
friend void inc_ref_count(StringData* s, void*)
{
++s->refcount;
}
friend void dec_ref_count(StringData* s, void*)
{
if (--s->refcount == 0)
StringData::destroy(s);
}
};
using StringDataPtr = RefPtr<StringData>;
class StringRegistry : public Singleton<StringRegistry>
{
public:
void debug_stats() const;
StringDataPtr intern(StringView str);
void purge_unused();
private:
UnorderedMap<StringView, StringDataPtr, MemoryDomain::SharedString> m_strings;
};
inline StringDataPtr intern(StringView str)
{
return StringRegistry::instance().intern(str);
}
}
#endif // shared_string_hh_INCLUDED