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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
namespace mongo {
inline Namespace& Namespace::operator=(const 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
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