// todo: this is called a lot. streamline the common case
MongoDataFile* Database::getFile( int n, int sizeNeeded , bool preallocateOnly) {
assert(this);
DEV assertDbAtLeastReadLocked(this);
namespaceIndex.init();
if ( n < 0 || n >= DiskLoc::MaxFiles ) {
out() << "getFile(): n=" << n << endl;
massert( 10295 , "getFile(): bad file number value (corrupt db?): run repair", false);
}
DEV {
if ( n > 100 ) {
out() << "getFile(): n=" << n << endl;
}
}
MongoDataFile* p = 0;
if ( !preallocateOnly ) {
while ( n >= (int) _files.size() ) {
DEV if( !d.dbMutex.isWriteLocked() ) {
log() << "error: getFile() called in a read lock, yet file to return is not yet open" << endl;
log() << " getFile(" << n << ") _files.size:" <<_files.size() << ' ' << fileName(n).string() << endl;
log() << " context ns: " << cc().ns() << " openallfiles:" << _openAllFiles << endl;
}
assertDbWriteLocked(this);
_files.push_back(0);
}
p = _files[n];
}
if ( p == 0 ) {
assertDbWriteLocked(this);
boost::filesystem::path fullName = fileName( n );
string fullNameString = fullName.string();
p = new MongoDataFile(n);
int minSize = 0;
if ( n != 0 && _files[ n - 1 ] )
minSize = _files[ n - 1 ]->getHeader()->fileLength;
if ( sizeNeeded + DataFileHeader::HeaderSize > minSize )
minSize = sizeNeeded + DataFileHeader::HeaderSize;
try {
p->open( fullNameString.c_str(), minSize, preallocateOnly );
}
catch ( AssertionException& ) {
delete p;
throw;
}
if ( preallocateOnly )
delete p;
else
_files[n] = p;
}
return preallocateOnly ? 0 : p;
}
MongoDataFile* Database::addAFile( int sizeNeeded, bool preallocateNextFile ) {
assertDbWriteLocked(this);
int n = (int) _files.size();
MongoDataFile *ret = getFile( n, sizeNeeded );
if ( preallocateNextFile )
preallocateAFile();
return ret;
}