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SingularityViewer/indra/llcommon/lluuid.h

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/**
* @file lluuid.h
*
* $LicenseInfo:firstyear=2000&license=viewerlgpl$
* Second Life Viewer Source Code
* Copyright (C) 2010, Linden Research, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License only.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA
* $/LicenseInfo$
*/
#ifndef LL_LLUUID_H
#define LL_LLUUID_H
#include <iostream>
#include <set>
#include <vector>
#include <functional>
#include <boost/functional/hash.hpp>
#include <boost/unordered_set.hpp>
#include "stdtypes.h"
#include "llpreprocessor.h"
#include <absl/hash/hash.h>
class LLMutex;
const S32 UUID_BYTES = 16;
const S32 UUID_WORDS = 4;
const S32 UUID_STR_LENGTH = 37; // actually wrong, should be 36 and use size below
const S32 UUID_STR_SIZE = 37;
const S32 UUID_BASE85_LENGTH = 21; // including the trailing NULL.
struct uuid_time_t {
U32 high;
U32 low;
};
class LL_COMMON_API LLUUID
{
public:
//
// CREATORS
//
LLUUID();
explicit LLUUID(const char *in_string); // Convert from string.
explicit LLUUID(const std::string& in_string); // Convert from string.
LLUUID(const LLUUID &in) = default;
LLUUID &operator=(const LLUUID &rhs) = default;
~LLUUID() = default;
//
// MANIPULATORS
//
void generate(); // Generate a new UUID
void generate(const std::string& stream); //Generate a new UUID based on hash of input stream
static LLUUID generateNewID(std::string stream = ""); //static version of above for use in initializer expressions such as constructor params, etc.
BOOL set(const char *in_string, BOOL emit = TRUE); // Convert from string, if emit is FALSE, do not emit warnings
BOOL set(const std::string& in_string, BOOL emit = TRUE); // Convert from string, if emit is FALSE, do not emit warnings
void setNull(); // Faster than setting to LLUUID::null.
S32 cmpTime(uuid_time_t *t1, uuid_time_t *t2);
static void getSystemTime(uuid_time_t *timestamp);
void getCurrentTime(uuid_time_t *timestamp);
//
// ACCESSORS
//
BOOL isNull() const; // Faster than comparing to LLUUID::null.
BOOL notNull() const; // Faster than comparing to LLUUID::null.
// JC: This is dangerous. It allows UUIDs to be cast automatically
// to integers, among other things. Use isNull() or notNull().
// operator bool() const;
// JC: These must return real bool's (not BOOLs) or else use of the STL
// will generate bool-to-int performance warnings.
bool operator==(const LLUUID &rhs) const;
bool operator!=(const LLUUID &rhs) const;
bool operator<(const LLUUID &rhs) const;
bool operator>(const LLUUID &rhs) const;
template <typename H>
friend H AbslHashValue(H h, const LLUUID& id) {
return H::combine_contiguous(std::move(h), id.mData, UUID_BYTES);
}
// xor functions. Useful since any two random uuids xored together
// will yield a determinate third random unique id that can be
// used as a key in a single uuid that represents 2.
const LLUUID& operator^=(const LLUUID& rhs);
LLUUID operator^(const LLUUID& rhs) const;
// similar to functions above, but not invertible
// yields a third random UUID that can be reproduced from the two inputs
// but which, given the result and one of the inputs can't be used to
// deduce the other input
LLUUID combine(const LLUUID& other) const;
void combine(const LLUUID& other, LLUUID& result) const;
friend LL_COMMON_API std::ostream& operator<<(std::ostream& s, const LLUUID &uuid);
friend LL_COMMON_API std::istream& operator>>(std::istream& s, LLUUID &uuid);
void toString(std::string& out) const;
void toCompressedString(std::string& out) const;
std::string asString() const;
std::string getString() const;
U16 getCRC16() const;
U32 getCRC32() const;
inline size_t hash() const
{
size_t seed = 0;
for (U8 i = 0; i < 4; ++i)
{
seed ^= static_cast<size_t>(mData[i * 4]) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
seed ^= static_cast<size_t>(mData[i * 4 + 1]) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
seed ^= static_cast<size_t>(mData[i * 4 + 2]) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
seed ^= static_cast<size_t>(mData[i * 4 + 3]) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
}
return seed;
}
static BOOL validate(const std::string& in_string); // Validate that the UUID string is legal.
static const LLUUID null;
static LLMutex * mMutex;
static U32 getRandomSeed();
static S32 getNodeID(unsigned char * node_id);
static BOOL parseUUID(const std::string& buf, LLUUID* value);
U8 mData[UUID_BYTES];
};
// Construct
inline LLUUID::LLUUID()
{
setNull();
}
// Faster than copying from memory
inline void LLUUID::setNull()
{
memset(mData, 0, sizeof(mData)); // <alchemy/>
}
// Compare
inline bool LLUUID::operator==(const LLUUID& rhs) const
{
return !memcmp(mData, rhs.mData, sizeof(mData)); // <alchemy/>
}
inline bool LLUUID::operator!=(const LLUUID& rhs) const
{
return !!memcmp(mData, rhs.mData, sizeof(mData)); // <alchemy/>
}
/*
// JC: This is dangerous. It allows UUIDs to be cast automatically
// to integers, among other things. Use isNull() or notNull().
inline LLUUID::operator bool() const
{
U32 *word = (U32 *)mData;
return (word[0] | word[1] | word[2] | word[3]) > 0;
}
*/
inline BOOL LLUUID::notNull() const
{
return !!memcmp(mData, null.mData, sizeof(mData)); // <alchemy/>
}
// Faster than == LLUUID::null because doesn't require
// as much memory access.
inline BOOL LLUUID::isNull() const
{
return !memcmp(mData, null.mData, sizeof(mData)); // <alchemy/>
}
inline LLUUID::LLUUID(const char *in_string)
{
if (!in_string || in_string[0] == 0)
{
setNull();
return;
}
set(in_string);
}
inline LLUUID::LLUUID(const std::string& in_string)
{
if (in_string.empty())
{
setNull();
return;
}
set(in_string);
}
// IW: DON'T "optimize" these w/ U32s or you'll scoogie the sort order
// IW: this will make me very sad
inline bool LLUUID::operator<(const LLUUID &rhs) const
{
U32 i;
for( i = 0; i < (UUID_BYTES - 1); i++ )
{
if( mData[i] != rhs.mData[i] )
{
return (mData[i] < rhs.mData[i]);
}
}
return (mData[UUID_BYTES - 1] < rhs.mData[UUID_BYTES - 1]);
}
inline bool LLUUID::operator>(const LLUUID &rhs) const
{
U32 i;
for( i = 0; i < (UUID_BYTES - 1); i++ )
{
if( mData[i] != rhs.mData[i] )
{
return (mData[i] > rhs.mData[i]);
}
}
return (mData[UUID_BYTES - 1] > rhs.mData[UUID_BYTES - 1]);
}
inline U16 LLUUID::getCRC16() const
{
// A UUID is 16 bytes, or 8 shorts.
U16 *short_data = (U16*)mData;
U16 out = 0;
out += short_data[0];
out += short_data[1];
out += short_data[2];
out += short_data[3];
out += short_data[4];
out += short_data[5];
out += short_data[6];
out += short_data[7];
return out;
}
inline U32 LLUUID::getCRC32() const
{
// <alchemy/>
U32 ret = 0;
for(U32 i = 0;i < 4;++i)
{
ret += (mData[i*4]) | (mData[i*4+1]) << 8 | (mData[i*4+2]) << 16 | (mData[i*4+3]) << 24;
}
return ret;
// </alchemy>
}
static_assert(std::is_trivially_copyable<LLUUID>::value, "LLUUID must be a trivially copyable type");
typedef std::vector<LLUUID> uuid_vec_t;
typedef boost::unordered_set<LLUUID> uuid_set_t;
// Helper structure for ordering lluuids in stl containers. eg:
// std::map<LLUUID, LLWidget*, lluuid_less> widget_map;
//
// (isn't this the default behavior anyway? I think we could
// everywhere replace these with uuid_set_t, but someone should
// verify.)
struct lluuid_less
{
bool operator()(const LLUUID& lhs, const LLUUID& rhs) const
{
return (lhs < rhs) ? true : false;
}
};
typedef std::set<LLUUID, lluuid_less> uuid_list_t;
namespace std {
template <> struct hash<LLUUID>
{
size_t operator()(const LLUUID & id) const
{
return absl::Hash<LLUUID>{}(id);
}
};
}
namespace boost {
template<> struct hash<LLUUID>
{
size_t operator()(const LLUUID& id) const
{
return absl::Hash<LLUUID>{}(id);
}
};
}
/*
* Sub-classes for keeping transaction IDs and asset IDs
* straight.
*/
typedef LLUUID LLAssetID;
class LL_COMMON_API LLTransactionID : public LLUUID
{
public:
LLTransactionID() : LLUUID() { }
static const LLTransactionID tnull;
LLAssetID makeAssetID(const LLUUID& session) const;
};
#endif