hash-str.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef COMMON_HASH_STR_H
#define COMMON_HASH_STR_H

#include "common/hashmap.h"
#include "common/str.h"

namespace Common {

uint hashit(const char *str);
uint hashit_lower(const char *str); // Generate a hash based on the lowercase version of the string
inline uint hashit_lower(const String &str) { return hashit_lower(str.c_str()); }

// FIXME: The following functors obviously are not consistently named

struct CaseSensitiveString_EqualTo {
    bool operator()(const String& x, const String& y) const { return x.equals(y); }
};

struct CaseSensitiveString_Hash {
    uint operator()(const String& x) const { return x.hash(); }
};


struct IgnoreCase_EqualTo {
    bool operator()(const String& x, const String& y) const { return x.equalsIgnoreCase(y); }
};

struct IgnoreCase_Hash {
    uint operator()(const String& x) const { return hashit_lower(x.c_str()); }
};

// Specalization of the Hash functor for String objects.
// We do case sensitve hashing here, because that is what
// the default EqualTo is compatible with. If one wants to use
// case insensitve hashing, then only because one wants to use
// IgnoreCase_EqualTo, and then one has to specify a custom
// hash anyway.
template<>
struct Hash<String> {
    uint operator()(const String& s) const {
        return s.hash();
    }
};

template<>
struct Hash<U32String> {
    uint operator()(const U32String& s) const {
        return s.hash();
    }
};

template<>
struct Hash<const char *> {
    uint operator()(const char *s) const {
        return hashit(s);
    }
};

// String map -- by default case insensitive
typedef HashMap<String, String, IgnoreCase_Hash, IgnoreCase_EqualTo> StringMap;

} // End of namespace Common

#endif