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// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// https://developers.google.com/protocol-buffers/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Author: kenton@google.com (Kenton Varda)
//
// Deals with the fact that hash_map is not defined everywhere.
#ifndef GOOGLE_PROTOBUF_STUBS_HASH_H__
#define GOOGLE_PROTOBUF_STUBS_HASH_H__
#include <string.h>
#include <google/protobuf/stubs/common.h>
#include <google/protobuf/stubs/pbconfig.h>
#if defined(GOOGLE_PROTOBUF_HAVE_HASH_MAP) && \
defined(GOOGLE_PROTOBUF_HAVE_HASH_SET)
#include GOOGLE_PROTOBUF_HASH_MAP_H
#include GOOGLE_PROTOBUF_HASH_SET_H
#else
#define GOOGLE_PROTOBUF_MISSING_HASH
#include <map>
#include <set>
#endif
namespace google {
namespace protobuf {
#ifdef GOOGLE_PROTOBUF_MISSING_HASH
// This system doesn't have hash_map or hash_set. Emulate them using map and
// set.
// Make hash<T> be the same as less<T>. Note that everywhere where custom
// hash functions are defined in the protobuf code, they are also defined such
// that they can be used as "less" functions, which is required by MSVC anyway.
template <typename Key>
struct hash {
// Dummy, just to make derivative hash functions compile.
int operator()(const Key& key) {
GOOGLE_LOG(FATAL) << "Should never be called.";
return 0;
}
inline bool operator()(const Key& a, const Key& b) const {
return a < b;
}
};
// Make sure char* is compared by value.
template <>
struct hash<const char*> {
// Dummy, just to make derivative hash functions compile.
int operator()(const char* key) {
GOOGLE_LOG(FATAL) << "Should never be called.";
return 0;
}
inline bool operator()(const char* a, const char* b) const {
return strcmp(a, b) < 0;
}
};
template <typename Key, typename Data,
typename HashFcn = hash<Key>,
typename EqualKey = std::equal_to<Key>,
typename Alloc = std::allocator< std::pair<const Key, Data> > >
class hash_map : public std::map<Key, Data, HashFcn, EqualKey, Alloc> {
public:
hash_map(int = 0, const HashFcn& = HashFcn(), const EqualKey& = EqualKey(),
const Alloc& = Alloc()) {}
};
template <typename Key,
typename HashFcn = hash<Key>,
typename EqualKey = std::equal_to<Key> >
class hash_set : public std::set<Key, HashFcn> {
public:
hash_set(int = 0) {}
};
#elif defined(_MSC_VER) && !defined(_STLPORT_VERSION)
template <typename Key>
struct hash : public GOOGLE_PROTOBUF_HASH_NAMESPACE::hash_compare<Key> {
};
// MSVC's hash_compare<const char*> hashes based on the string contents but
// compares based on the string pointer. WTF?
class CstringLess {
public:
inline bool operator()(const char* a, const char* b) const {
return strcmp(a, b) < 0;
}
};
template <>
struct hash<const char*>
: public GOOGLE_PROTOBUF_HASH_NAMESPACE::hash_compare<
const char*, CstringLess> {};
template <typename Key, typename Data,
typename HashFcn = hash<Key>,
typename EqualKey = std::equal_to<Key>,
typename Alloc = std::allocator< std::pair<const Key, Data> > >
class hash_map
: public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_MAP_CLASS<
Key, Data, HashFcn, EqualKey, Alloc> {
public:
hash_map(int = 0, const HashFcn& = HashFcn(), const EqualKey& = EqualKey(),
const Alloc& = Alloc()) {}
};
template <typename Key, typename HashFcn = hash<Key>,
typename EqualKey = std::equal_to<Key> >
class hash_set
: public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_SET_CLASS<
Key, HashFcn, EqualKey> {
public:
hash_set(int = 0) {}
};
#else
template <typename Key>
struct hash : public GOOGLE_PROTOBUF_HASH_NAMESPACE::hash<Key> {
};
template <typename Key>
struct hash<const Key*> {
inline size_t operator()(const Key* key) const {
return reinterpret_cast<size_t>(key);
}
};
// Unlike the old SGI version, the TR1 "hash" does not special-case char*. So,
// we go ahead and provide our own implementation.
template <>
struct hash<const char*> {
inline size_t operator()(const char* str) const {
size_t result = 0;
for (; *str != '\0'; str++) {
result = 5 * result + *str;
}
return result;
}
};
template <typename Key, typename Data,
typename HashFcn = hash<Key>,
typename EqualKey = std::equal_to<Key>,
typename Alloc = std::allocator< std::pair<const Key, Data> > >
class hash_map
: public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_MAP_CLASS<
Key, Data, HashFcn, EqualKey, Alloc> {
public:
hash_map(int = 0, const HashFcn& = HashFcn(), const EqualKey& = EqualKey(),
const Alloc& = Alloc()) {}
};
template <typename Key, typename HashFcn = hash<Key>,
typename EqualKey = std::equal_to<Key> >
class hash_set
: public GOOGLE_PROTOBUF_HASH_NAMESPACE::GOOGLE_PROTOBUF_HASH_SET_CLASS<
Key, HashFcn, EqualKey> {
public:
hash_set(int = 0) {}
};
#undef GOOGLE_PROTOBUF_MISSING_HASH
#endif // !GOOGLE_PROTOBUF_MISSING_HASH
template <>
struct hash<string> {
inline size_t operator()(const string& key) const {
return hash<const char*>()(key.c_str());
}
static const size_t bucket_size = 4;
static const size_t min_buckets = 8;
inline size_t operator()(const string& a, const string& b) const {
return a < b;
}
};
template <typename First, typename Second>
struct hash<pair<First, Second> > {
inline size_t operator()(const pair<First, Second>& key) const {
size_t first_hash = hash<First>()(key.first);
size_t second_hash = hash<Second>()(key.second);
// FIXME(kenton): What is the best way to compute this hash? I have
// no idea! This seems a bit better than an XOR.
return first_hash * ((1 << 16) - 1) + second_hash;
}
static const size_t bucket_size = 4;
static const size_t min_buckets = 8;
inline size_t operator()(const pair<First, Second>& a,
const pair<First, Second>& b) const {
return a < b;
}
};
// Used by GCC/SGI STL only. (Why isn't this provided by the standard
// library? :( )
struct streq {
inline bool operator()(const char* a, const char* b) const {
return strcmp(a, b) == 0;
}
};
} // namespace protobuf
} // namespace google
#endif // GOOGLE_PROTOBUF_STUBS_HASH_H__