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// namespace-inl.h

/**
*    Copyright (C) 2009 10gen Inc.
*
*    This program is free software: you can redistribute it and/or  modify
*    it under the terms of the GNU Affero General Public License, version 3,
*    as published by the Free Software Foundation.
*
*    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 Affero General Public License for more details.
*
*    You should have received a copy of the GNU Affero General Public License
*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*
*    As a special exception, the copyright holders give permission to link the
*    code of portions of this program with the OpenSSL library under certain
*    conditions as described in each individual source file and distribute
*    linked combinations including the program with the OpenSSL library. You
*    must comply with the GNU Affero General Public License in all respects for
*    all of the code used other than as permitted herein. If you modify file(s)
*    with this exception, you may extend this exception to your version of the
*    file(s), but you are not obligated to do so. If you do not wish to do so,
*    delete this exception statement from your version. If you delete this
*    exception statement from all source files in the program, then also delete
*    it in the license file.
*/

#pragma once

#include <boost/filesystem/path.hpp>

#include "mongo/util/assert_util.h"

namespace mongo {

inline Namespace& Namespace::operator=(StringData ns) {
    // we fill the remaining space with all zeroes here.  as the full Namespace struct is in
    // the datafiles (the .ns files specifically), that is helpful as then they are deterministic
    // in the bytes they have for a given sequence of operations.  that makes testing and debugging
    // the data files easier.
    //
    // if profiling indicates this method is a significant bottleneck, we could have a version we
    // use for reads which does not fill with zeroes, and keep the zeroing behavior on writes.
    //
    memset(buf, 0, sizeof(buf));
    uassert(10080, "ns name too long, max size is 127 bytes", ns.size() <= MaxNsLen);
    uassert(17380, "ns name can't contain embedded '\0' byte", ns.find('\0') == std::string::npos);
    ns.copyTo(buf, true);
    return *this;
}

inline std::string Namespace::extraName(int i) const {
    char ex[] = "$extra";
    ex[5] += i;
    std::string s = std::string(buf) + ex;
    massert(10348, "$extra: ns name too long", s.size() <= MaxNsLen);
    return s;
}

inline bool Namespace::isExtra() const {
    const char* p = strstr(buf, "$extr");
    return p && p[5] &&
        p[6] == 0;  //==0 important in case an index uses name "$extra_1" for example
}

inline int Namespace::hash() const {
    unsigned x = 0;
    const char* p = buf;
    while (*p) {
        x = x * 131 + *p;
        p++;
    }
    return (x & 0x7fffffff) | 0x8000000;  // must be > 0
}

}  // namespace mongo