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pdfile.cpp
2018 lines (1767 loc) · 74.9 KB
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pdfile.cpp
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// pdfile.cpp
/**
* Copyright (C) 2008 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/>.
*/
/*
todo:
_ table scans must be sequential, not next/prev pointers
_ coalesce deleted
_ disallow system* manipulations from the database.
*/
#include "pch.h"
#include "pdfile.h"
#include "db.h"
#include "../util/mmap.h"
#include "../util/hashtab.h"
#include "../util/file_allocator.h"
#include "../util/processinfo.h"
#include "btree.h"
#include <algorithm>
#include <list>
#include "query.h"
#include "repl.h"
#include "dbhelpers.h"
#include "namespace-inl.h"
#include "queryutil.h"
#include "extsort.h"
#include "curop-inl.h"
#include "background.h"
namespace mongo {
bool inDBRepair = false;
struct doingRepair {
doingRepair(){
assert( ! inDBRepair );
inDBRepair = true;
}
~doingRepair(){
inDBRepair = false;
}
};
map<string, unsigned> BackgroundOperation::dbsInProg;
set<string> BackgroundOperation::nsInProg;
bool BackgroundOperation::inProgForDb(const char *db) {
assertInWriteLock();
return dbsInProg[db] != 0;
}
bool BackgroundOperation::inProgForNs(const char *ns) {
assertInWriteLock();
return nsInProg.count(ns) != 0;
}
void BackgroundOperation::assertNoBgOpInProgForDb(const char *db) {
uassert(12586, "cannot perform operation: a background operation is currently running for this database",
!inProgForDb(db));
}
void BackgroundOperation::assertNoBgOpInProgForNs(const char *ns) {
uassert(12587, "cannot perform operation: a background operation is currently running for this collection",
!inProgForNs(ns));
}
BackgroundOperation::BackgroundOperation(const char *ns) : _ns(ns) {
assertInWriteLock();
dbsInProg[_ns.db]++;
assert( nsInProg.count(_ns.ns()) == 0 );
nsInProg.insert(_ns.ns());
}
BackgroundOperation::~BackgroundOperation() {
assertInWriteLock();
dbsInProg[_ns.db]--;
nsInProg.erase(_ns.ns());
}
void BackgroundOperation::dump(stringstream& ss) {
if( nsInProg.size() ) {
ss << "\n<b>Background Jobs in Progress</b>\n";
for( set<string>::iterator i = nsInProg.begin(); i != nsInProg.end(); i++ )
ss << " " << *i << '\n';
}
for( map<string,unsigned>::iterator i = dbsInProg.begin(); i != dbsInProg.end(); i++ ) {
if( i->second )
ss << "database " << i->first << ": " << i->second << '\n';
}
}
/* ----------------------------------------- */
string dbpath = "/data/db/";
bool directoryperdb = false;
string repairpath;
string pidfilepath;
DataFileMgr theDataFileMgr;
DatabaseHolder dbHolder;
int MAGIC = 0x1000;
extern int otherTraceLevel;
void addNewNamespaceToCatalog(const char *ns, const BSONObj *options = 0);
void ensureIdIndexForNewNs(const char *ns) {
if ( ( strstr( ns, ".system." ) == 0 || legalClientSystemNS( ns , false ) ) &&
strstr( ns, ".$freelist" ) == 0 ){
log( 1 ) << "adding _id index for collection " << ns << endl;
ensureHaveIdIndex( ns );
}
}
string getDbContext() {
stringstream ss;
Client * c = currentClient.get();
if ( c ){
Client::Context * cx = c->getContext();
if ( cx ){
Database *database = cx->db();
if ( database ) {
ss << database->name << ' ';
ss << cx->ns() << ' ';
}
}
}
return ss.str();
}
/*---------------------------------------------------------------------*/
// inheritable class to implement an operation that may be applied to all
// files in a database using _applyOpToDataFiles()
class FileOp {
public:
virtual ~FileOp() {}
// Return true if file exists and operation successful
virtual bool apply( const boost::filesystem::path &p ) = 0;
virtual const char * op() const = 0;
};
void _applyOpToDataFiles( const char *database, FileOp &fo, bool afterAllocator = false, const string& path = dbpath );
void _deleteDataFiles(const char *database) {
if ( directoryperdb ) {
BOOST_CHECK_EXCEPTION( boost::filesystem::remove_all( boost::filesystem::path( dbpath ) / database ) );
return;
}
class : public FileOp {
virtual bool apply( const boost::filesystem::path &p ) {
return boost::filesystem::remove( p );
}
virtual const char * op() const {
return "remove";
}
} deleter;
_applyOpToDataFiles( database, deleter, true );
}
int Extent::initialSize(int len) {
long long sz = len * 16;
if ( len < 1000 ) sz = len * 64;
if ( sz > 1000000000 )
sz = 1000000000;
int z = ((int)sz) & 0xffffff00;
assert( z > len );
return z;
}
bool _userCreateNS(const char *ns, const BSONObj& options, string& err, bool *deferIdIndex) {
if ( nsdetails(ns) ) {
err = "collection already exists";
return false;
}
log(1) << "create collection " << ns << ' ' << options << '\n';
/* todo: do this only when we have allocated space successfully? or we could insert with a { ok: 0 } field
and then go back and set to ok : 1 after we are done.
*/
bool isFreeList = strstr(ns, ".$freelist") != 0;
if( !isFreeList )
addNewNamespaceToCatalog(ns, options.isEmpty() ? 0 : &options);
long long size = Extent::initialSize(128);
{
BSONElement e = options.getField("size");
if ( e.isNumber() ) {
size = e.numberLong();
size += 256;
size &= 0xffffffffffffff00LL;
}
}
uassert( 10083 , "invalid size spec", size > 0 );
bool newCapped = false;
int mx = 0;
if( options.getBoolField("capped") ) {
newCapped = true;
BSONElement e = options.getField("max");
if ( e.isNumber() ) {
mx = e.numberInt();
}
}
// $nExtents just for debug/testing.
BSONElement e = options.getField( "$nExtents" );
Database *database = cc().database();
if ( e.type() == Array ) {
// We create one extent per array entry, with size specified
// by the array value.
BSONObjIterator i( e.embeddedObject() );
while( i.more() ) {
BSONElement e = i.next();
int size = int( e.number() );
assert( size <= 0x7fffffff );
// $nExtents is just for testing - always allocate new extents
// rather than reuse existing extents so we have some predictibility
// in the extent size used by our tests
database->suitableFile( (int) size, false )->createExtent( ns, (int) size, newCapped );
}
} else if ( int( e.number() ) > 0 ) {
// We create '$nExtents' extents, each of size 'size'.
int nExtents = int( e.number() );
assert( size <= 0x7fffffff );
for ( int i = 0; i < nExtents; ++i ) {
assert( size <= 0x7fffffff );
// $nExtents is just for testing - always allocate new extents
// rather than reuse existing extents so we have some predictibility
// in the extent size used by our tests
database->suitableFile( (int) size, false )->createExtent( ns, (int) size, newCapped );
}
} else {
// This is the non test case, where we don't have a $nExtents spec.
while ( size > 0 ) {
int max = MongoDataFile::maxSize() - DataFileHeader::HeaderSize;
int desiredExtentSize = (int) (size > max ? max : size);
Extent *e = database->allocExtent( ns, desiredExtentSize, newCapped );
size -= e->length;
}
}
NamespaceDetails *d = nsdetails(ns);
assert(d);
bool ensure = false;
if ( options.getField( "autoIndexId" ).type() ) {
if ( options["autoIndexId"].trueValue() ){
ensure = true;
}
} else {
if ( !newCapped ) {
ensure=true;
}
}
if( ensure ) {
if( deferIdIndex )
*deferIdIndex = true;
else
ensureIdIndexForNewNs( ns );
}
if ( mx > 0 )
getDur().writingInt( d->max ) = mx;
return true;
}
/** { ..., capped: true, size: ..., max: ... }
@param deferIdIndex - if not not, defers id index creation. sets the bool value to true if we wanted to create the id index.
@return true if successful
*/
bool userCreateNS(const char *ns, BSONObj options, string& err, bool logForReplication, bool *deferIdIndex) {
const char *coll = strchr( ns, '.' ) + 1;
massert( 10356 , str::stream() << "invalid ns: " << ns , coll && *coll );
char cl[ 256 ];
nsToDatabase( ns, cl );
bool ok = _userCreateNS(ns, options, err, deferIdIndex);
if ( logForReplication && ok ) {
if ( options.getField( "create" ).eoo() ) {
BSONObjBuilder b;
b << "create" << coll;
b.appendElements( options );
options = b.obj();
}
string logNs = string( cl ) + ".$cmd";
logOp("c", logNs.c_str(), options);
}
return ok;
}
/*---------------------------------------------------------------------*/
int MongoDataFile::maxSize() {
if ( sizeof( int* ) == 4 ) {
return 512 * 1024 * 1024;
} else if ( cmdLine.smallfiles ) {
return 0x7ff00000 >> 2;
} else {
return 0x7ff00000;
}
}
void MongoDataFile::badOfs2(int ofs) const {
stringstream ss;
ss << "bad offset:" << ofs << " accessing file: " << mmf.filename() << " - consider repairing database";
uasserted(13441, ss.str());
}
void MongoDataFile::badOfs(int ofs) const {
stringstream ss;
ss << "bad offset:" << ofs << " accessing file: " << mmf.filename() << " - consider repairing database";
uasserted(13440, ss.str());
}
int MongoDataFile::defaultSize( const char *filename ) const {
int size;
if ( fileNo <= 4 )
size = (64*1024*1024) << fileNo;
else
size = 0x7ff00000;
if ( strstr(filename, "_hudsonSmall") ) {
int mult = 1;
if ( fileNo > 1 && fileNo < 1000 )
mult = fileNo;
size = 1024 * 512 * mult;
log() << "Warning : using small files for _hudsonSmall" << endl;
}
else if ( cmdLine.smallfiles ){
size = size >> 2;
}
return size;
}
void MongoDataFile::open( const char *filename, int minSize, bool preallocateOnly ) {
{
/* check quotas
very simple temporary implementation for now
*/
if ( cmdLine.quota && fileNo > cmdLine.quotaFiles && !MMF::exists(filename) ) {
/* todo: if we were adding / changing keys in an index did we do some
work previously that needs cleaning up? Possible. We should
check code like that and have it catch the exception and do
something reasonable.
*/
string s = "db disk space quota exceeded ";
Database *database = cc().database();
if ( database )
s += database->name;
uasserted(12501,s);
}
}
long size = defaultSize( filename );
while ( size < minSize ) {
if ( size < maxSize() / 2 )
size *= 2;
else {
size = maxSize();
break;
}
}
if ( size > maxSize() )
size = maxSize();
assert( size >= 64*1024*1024 || cmdLine.smallfiles );
assert( size % 4096 == 0 );
if ( preallocateOnly ) {
if ( cmdLine.prealloc ) {
theFileAllocator().requestAllocation( filename, size );
}
return;
}
{
assert( _mb == 0 );
unsigned long long sz = size;
if( mmf.create(filename, sz, false) )
_mb = mmf.getView();
assert( sz <= 0x7fffffff );
size = (int) sz;
}
//header = (DataFileHeader *) _p;
if( sizeof(char *) == 4 )
uassert( 10084 , "can't map file memory - mongo requires 64 bit build for larger datasets", _mb != 0);
else
uassert( 10085 , "can't map file memory", _mb != 0);
header()->init(fileNo, size);
}
void MongoDataFile::flush( bool sync ){
mmf.flush( sync );
}
void addNewExtentToNamespace(const char *ns, Extent *e, DiskLoc eloc, DiskLoc emptyLoc, bool capped) {
NamespaceIndex *ni = nsindex(ns);
NamespaceDetails *details = ni->details(ns);
if ( details ) {
assert( !details->lastExtent.isNull() );
assert( !details->firstExtent.isNull() );
getDur().writingDiskLoc(e->xprev) = details->lastExtent;
getDur().writingDiskLoc(details->lastExtent.ext()->xnext) = eloc;
assert( !eloc.isNull() );
getDur().writingDiskLoc(details->lastExtent) = eloc;
}
else {
ni->add_ns(ns, eloc, capped);
details = ni->details(ns);
}
{
NamespaceDetails *dw = details->writingWithoutExtra();
dw->lastExtentSize = e->length;
}
details->addDeletedRec(emptyLoc.drec(), emptyLoc);
}
Extent* MongoDataFile::createExtent(const char *ns, int approxSize, bool newCapped, int loops) {
massert( 10357 , "shutdown in progress", ! inShutdown() );
massert( 10358 , "bad new extent size", approxSize >= 0 && approxSize <= Extent::maxSize() );
massert( 10359 , "header==0 on new extent: 32 bit mmap space exceeded?", header() ); // null if file open failed
int ExtentSize = approxSize <= header()->unusedLength ? approxSize : header()->unusedLength;
DiskLoc loc;
if ( ExtentSize <= 0 ) {
/* not there could be a lot of looping here is db just started and
no files are open yet. we might want to do something about that. */
if ( loops > 8 ) {
assert( loops < 10000 );
out() << "warning: loops=" << loops << " fileno:" << fileNo << ' ' << ns << '\n';
}
log() << "newExtent: " << ns << " file " << fileNo << " full, adding a new file\n";
return cc().database()->addAFile( 0, true )->createExtent(ns, approxSize, newCapped, loops+1);
}
int offset = header()->unused.getOfs();
DataFileHeader *h = getDur().writing(header());
h->unused.set( fileNo, offset + ExtentSize );
h->unusedLength -= ExtentSize;
loc.set(fileNo, offset);
Extent *e = _getExtent(loc);
DiskLoc emptyLoc = getDur().writing(e)->init(ns, ExtentSize, fileNo, offset);
addNewExtentToNamespace(ns, e, loc, emptyLoc, newCapped);
DEV tlog(1) << "new extent " << ns << " size: 0x" << hex << ExtentSize << " loc: 0x" << hex << offset
<< " emptyLoc:" << hex << emptyLoc.getOfs() << dec << endl;
return e;
}
Extent* DataFileMgr::allocFromFreeList(const char *ns, int approxSize, bool capped) {
string s = cc().database()->name + ".$freelist";
NamespaceDetails *f = nsdetails(s.c_str());
if( f ) {
int low, high;
if( capped ) {
// be strict about the size
low = approxSize;
if( low > 2048 ) low -= 256;
high = (int) (approxSize * 1.05) + 256;
}
else {
low = (int) (approxSize * 0.8);
high = (int) (approxSize * 1.4);
}
if( high < 0 ) high = approxSize;
int n = 0;
Extent *best = 0;
int bestDiff = 0x7fffffff;
{
DiskLoc L = f->firstExtent;
while( !L.isNull() ) {
Extent * e = L.ext();
if( e->length >= low && e->length <= high ) {
int diff = abs(e->length - approxSize);
if( diff < bestDiff ) {
bestDiff = diff;
best = e;
if( diff == 0 )
break;
}
}
L = e->xnext;
++n;
}
}
OCCASIONALLY if( n > 512 ) log() << "warning: newExtent " << n << " scanned\n";
if( best ) {
Extent *e = best;
// remove from the free list
if( !e->xprev.isNull() )
e->xprev.ext()->xnext.writing() = e->xnext;
if( !e->xnext.isNull() )
e->xnext.ext()->xprev.writing() = e->xprev;
if( f->firstExtent == e->myLoc )
f->firstExtent.writing() = e->xnext;
if( f->lastExtent == e->myLoc )
f->lastExtent.writing() = e->xprev;
// use it
OCCASIONALLY if( n > 512 ) log() << "warning: newExtent " << n << " scanned\n";
DiskLoc emptyLoc = e->reuse(ns);
addNewExtentToNamespace(ns, e, e->myLoc, emptyLoc, capped);
return e;
}
}
return 0;
// return createExtent(ns, approxSize, capped);
}
/*---------------------------------------------------------------------*/
DiskLoc Extent::reuse(const char *nsname) {
return getDur().writing(this)->_reuse(nsname);
}
DiskLoc Extent::_reuse(const char *nsname) {
log(3) << "reset extent was:" << nsDiagnostic.toString() << " now:" << nsname << '\n';
massert( 10360 , "Extent::reset bad magic value", magic == 0x41424344 );
xnext.Null();
xprev.Null();
nsDiagnostic = nsname;
firstRecord.Null();
lastRecord.Null();
DiskLoc emptyLoc = myLoc;
emptyLoc.inc( (int) (_extentData-(char*)this) );
int delRecLength = length - (_extentData - (char *) this);
DeletedRecord *empty = DataFileMgr::makeDeletedRecord(emptyLoc, delRecLength);//(DeletedRecord *) getRecord(emptyLoc);
empty = getDur().writing(empty);
empty->lengthWithHeaders = delRecLength;
empty->extentOfs = myLoc.getOfs();
empty->nextDeleted.Null();
return emptyLoc;
}
/* assumes already zeroed -- insufficient for block 'reuse' perhaps */
DiskLoc Extent::init(const char *nsname, int _length, int _fileNo, int _offset) {
magic = 0x41424344;
myLoc.set(_fileNo, _offset);
xnext.Null();
xprev.Null();
nsDiagnostic = nsname;
length = _length;
firstRecord.Null();
lastRecord.Null();
DiskLoc emptyLoc = myLoc;
emptyLoc.inc( (int) (_extentData-(char*)this) );
int l = _length - (_extentData - (char *) this);
DeletedRecord *empty = getDur().writing( DataFileMgr::makeDeletedRecord(emptyLoc, l) );
empty->lengthWithHeaders = l;
empty->extentOfs = myLoc.getOfs();
return emptyLoc;
}
/*
Record* Extent::newRecord(int len) {
if( firstEmptyRegion.isNull() )8
return 0;
assert(len > 0);
int newRecSize = len + Record::HeaderSize;
DiskLoc newRecordLoc = firstEmptyRegion;
Record *r = getRecord(newRecordLoc);
int left = r->netLength() - len;
if( left < 0 ) {
//
firstEmptyRegion.Null();
return 0;
}
DiskLoc nextEmpty = r->next.getNextEmpty(firstEmptyRegion);
r->lengthWithHeaders = newRecSize;
r->next.markAsFirstOrLastInExtent(this); // we're now last in the extent
if( !lastRecord.isNull() ) {
assert(getRecord(lastRecord)->next.lastInExtent()); // it was the last one
getRecord(lastRecord)->next.set(newRecordLoc); // until now
r->prev.set(lastRecord);
}
else {
r->prev.markAsFirstOrLastInExtent(this); // we are the first in the extent
assert( firstRecord.isNull() );
firstRecord = newRecordLoc;
}
lastRecord = newRecordLoc;
if( left < Record::HeaderSize + 32 ) {
firstEmptyRegion.Null();
}
else {
firstEmptyRegion.inc(newRecSize);
Record *empty = getRecord(firstEmptyRegion);
empty->next.set(nextEmpty); // not for empty records, unless in-use records, next and prev can be null.
empty->prev.Null();
empty->lengthWithHeaders = left;
}
return r;
}
*/
int Extent::maxSize() {
int maxExtentSize = 0x7ff00000;
if ( cmdLine.smallfiles ) {
maxExtentSize >>= 2;
}
return maxExtentSize;
}
/*---------------------------------------------------------------------*/
shared_ptr<Cursor> DataFileMgr::findAll(const char *ns, const DiskLoc &startLoc) {
NamespaceDetails * d = nsdetails( ns );
if ( ! d )
return shared_ptr<Cursor>(new BasicCursor(DiskLoc()));
DiskLoc loc = d->firstExtent;
Extent *e = getExtent(loc);
DEBUGGING {
out() << "listing extents for " << ns << endl;
DiskLoc tmp = loc;
set<DiskLoc> extents;
while ( 1 ) {
Extent *f = getExtent(tmp);
out() << "extent: " << tmp.toString() << endl;
extents.insert(tmp);
tmp = f->xnext;
if ( tmp.isNull() )
break;
f = f->getNextExtent();
}
out() << endl;
d->dumpDeleted(&extents);
}
if ( d->capped )
return shared_ptr<Cursor>( new ForwardCappedCursor( d , startLoc ) );
if ( !startLoc.isNull() )
return shared_ptr<Cursor>(new BasicCursor( startLoc ));
while ( e->firstRecord.isNull() && !e->xnext.isNull() ) {
/* todo: if extent is empty, free it for reuse elsewhere.
that is a bit complicated have to clean up the freelists.
*/
RARELY out() << "info DFM::findAll(): extent " << loc.toString() << " was empty, skipping ahead " << ns << endl;
// find a nonempty extent
// it might be nice to free the whole extent here! but have to clean up free recs then.
e = e->getNextExtent();
}
return shared_ptr<Cursor>(new BasicCursor( e->firstRecord ));
}
/* get a table scan cursor, but can be forward or reverse direction.
order.$natural - if set, > 0 means forward (asc), < 0 backward (desc).
*/
shared_ptr<Cursor> findTableScan(const char *ns, const BSONObj& order, const DiskLoc &startLoc) {
BSONElement el = order.getField("$natural"); // e.g., { $natural : -1 }
if ( el.number() >= 0 )
return DataFileMgr::findAll(ns, startLoc);
// "reverse natural order"
NamespaceDetails *d = nsdetails(ns);
if ( !d )
return shared_ptr<Cursor>(new BasicCursor(DiskLoc()));
if ( !d->capped ) {
if ( !startLoc.isNull() )
return shared_ptr<Cursor>(new ReverseCursor( startLoc ));
Extent *e = d->lastExtent.ext();
while ( e->lastRecord.isNull() && !e->xprev.isNull() ) {
OCCASIONALLY out() << " findTableScan: extent empty, skipping ahead" << endl;
e = e->getPrevExtent();
}
return shared_ptr<Cursor>(new ReverseCursor( e->lastRecord ));
} else {
return shared_ptr<Cursor>( new ReverseCappedCursor( d, startLoc ) );
}
}
void printFreeList() {
string s = cc().database()->name + ".$freelist";
log() << "dump freelist " << s << '\n';
NamespaceDetails *freeExtents = nsdetails(s.c_str());
if( freeExtents == 0 ) {
log() << " freeExtents==0" << endl;
return;
}
DiskLoc a = freeExtents->firstExtent;
while( !a.isNull() ) {
Extent *e = a.ext();
log() << " " << a.toString() << " len:" << e->length << " prev:" << e->xprev.toString() << '\n';
a = e->xnext;
}
log() << " end freelist" << endl;
}
/* drop a collection/namespace */
void dropNS(const string& nsToDrop) {
NamespaceDetails* d = nsdetails(nsToDrop.c_str());
uassert( 10086 , (string)"ns not found: " + nsToDrop , d );
BackgroundOperation::assertNoBgOpInProgForNs(nsToDrop.c_str());
NamespaceString s(nsToDrop);
assert( s.db == cc().database()->name );
if( s.isSystem() ) {
if( s.coll == "system.profile" )
uassert( 10087 , "turn off profiling before dropping system.profile collection", cc().database()->profile == 0 );
else
uasserted( 12502, "can't drop system ns" );
}
{
// remove from the system catalog
BSONObj cond = BSON( "name" << nsToDrop ); // { name: "colltodropname" }
string system_namespaces = cc().database()->name + ".system.namespaces";
/*int n = */ deleteObjects(system_namespaces.c_str(), cond, false, false, true);
// no check of return code as this ns won't exist for some of the new storage engines
}
// free extents
if( !d->firstExtent.isNull() ) {
string s = cc().database()->name + ".$freelist";
NamespaceDetails *freeExtents = nsdetails(s.c_str());
if( freeExtents == 0 ) {
string err;
_userCreateNS(s.c_str(), BSONObj(), err, 0);
freeExtents = nsdetails(s.c_str());
massert( 10361 , "can't create .$freelist", freeExtents);
}
if( freeExtents->firstExtent.isNull() ) {
freeExtents->firstExtent.writing() = d->firstExtent;
freeExtents->lastExtent.writing() = d->lastExtent;
}
else {
DiskLoc a = freeExtents->firstExtent;
assert( a.ext()->xprev.isNull() );
getDur().writingDiskLoc( a.ext()->xprev ) = d->lastExtent;
getDur().writingDiskLoc( d->lastExtent.ext()->xnext ) = a;
getDur().writingDiskLoc( freeExtents->firstExtent ) = d->firstExtent;
getDur().writingDiskLoc( d->firstExtent ).setInvalid();
getDur().writingDiskLoc( d->lastExtent ).setInvalid();
}
}
// remove from the catalog hashtable
cc().database()->namespaceIndex.kill_ns(nsToDrop.c_str());
}
void dropCollection( const string &name, string &errmsg, BSONObjBuilder &result ) {
log(1) << "dropCollection: " << name << endl;
NamespaceDetails *d = nsdetails(name.c_str());
if( d == 0 )
return;
BackgroundOperation::assertNoBgOpInProgForNs(name.c_str());
if ( d->nIndexes != 0 ) {
try {
assert( dropIndexes(d, name.c_str(), "*", errmsg, result, true) );
}
catch( DBException& e ) {
stringstream ss;
ss << "drop: dropIndexes for collection failed - consider trying repair ";
ss << " cause: " << e.what();
uasserted(12503,ss.str());
}
assert( d->nIndexes == 0 );
}
log(1) << "\t dropIndexes done" << endl;
result.append("ns", name.c_str());
ClientCursor::invalidate(name.c_str());
Top::global.collectionDropped( name );
dropNS(name);
}
int nUnindexes = 0;
/* unindex all keys in index for this record. */
static void _unindexRecord(IndexDetails& id, BSONObj& obj, const DiskLoc& dl, bool logMissing = true) {
BSONObjSetDefaultOrder keys;
id.getKeysFromObject(obj, keys);
for ( BSONObjSetDefaultOrder::iterator i=keys.begin(); i != keys.end(); i++ ) {
BSONObj j = *i;
if ( otherTraceLevel >= 5 ) {
out() << "_unindexRecord() " << obj.toString();
out() << "\n unindex:" << j.toString() << endl;
}
nUnindexes++;
bool ok = false;
try {
ok = id.head.btree()->unindex(id.head, id, j, dl);
}
catch (AssertionException& e) {
problem() << "Assertion failure: _unindex failed " << id.indexNamespace() << endl;
out() << "Assertion failure: _unindex failed: " << e.what() << '\n';
out() << " obj:" << obj.toString() << '\n';
out() << " key:" << j.toString() << '\n';
out() << " dl:" << dl.toString() << endl;
sayDbContext();
}
if ( !ok && logMissing ) {
out() << "unindex failed (key too big?) " << id.indexNamespace() << '\n';
}
}
}
/* unindex all keys in all indexes for this record. */
static void unindexRecord(NamespaceDetails *d, Record *todelete, const DiskLoc& dl, bool noWarn = false) {
BSONObj obj(todelete);
int n = d->nIndexes;
for ( int i = 0; i < n; i++ )
_unindexRecord(d->idx(i), obj, dl, !noWarn);
if( d->backgroundIndexBuildInProgress ) {
// always pass nowarn here, as this one may be missing for valid reasons as we are concurrently building it
_unindexRecord(d->idx(n), obj, dl, false);
}
}
/* deletes a record, just the pdfile portion -- no index cleanup, no cursor cleanup, etc.
caller must check if capped
*/
void DataFileMgr::_deleteRecord(NamespaceDetails *d, const char *ns, Record *todelete, const DiskLoc& dl)
{
/* remove ourself from the record next/prev chain */
{
if ( todelete->prevOfs != DiskLoc::NullOfs )
getDur().writingInt( todelete->getPrev(dl).rec()->nextOfs ) = todelete->nextOfs;
if ( todelete->nextOfs != DiskLoc::NullOfs )
getDur().writingInt( todelete->getNext(dl).rec()->prevOfs ) = todelete->prevOfs;
}
/* remove ourself from extent pointers */
{
Extent *e = getDur().writing( todelete->myExtent(dl) );
if ( e->firstRecord == dl ) {
if ( todelete->nextOfs == DiskLoc::NullOfs )
e->firstRecord.Null();
else
e->firstRecord.set(dl.a(), todelete->nextOfs);
}
if ( e->lastRecord == dl ) {
if ( todelete->prevOfs == DiskLoc::NullOfs )
e->lastRecord.Null();
else
e->lastRecord.set(dl.a(), todelete->prevOfs);
}
}
/* add to the free list */
{
{
NamespaceDetails::Stats *s = getDur().writing(&d->stats);
s->datasize -= todelete->netLength();
s->nrecords--;
}
if ( strstr(ns, ".system.indexes") ) {
/* temp: if in system.indexes, don't reuse, and zero out: we want to be
careful until validated more, as IndexDetails has pointers
to this disk location. so an incorrectly done remove would cause
a lot of problems.
*/
memset(getDur().writingPtr(todelete, todelete->lengthWithHeaders), 0, todelete->lengthWithHeaders);
}
else {
DEV {
unsigned long long *p = (unsigned long long *) todelete->data;
*getDur().writing(p) = 0;
//DEV memset(todelete->data, 0, todelete->netLength()); // attempt to notice invalid reuse.
}
d->addDeletedRec((DeletedRecord*)todelete, dl);
}
}
}
void DataFileMgr::deleteRecord(const char *ns, Record *todelete, const DiskLoc& dl, bool cappedOK, bool noWarn)
{
dassert( todelete == dl.rec() );
NamespaceDetails* d = nsdetails(ns);
if ( d->capped && !cappedOK ) {
out() << "failing remove on a capped ns " << ns << endl;
uassert( 10089 , "can't remove from a capped collection" , 0 );
return;
}
/* check if any cursors point to us. if so, advance them. */
ClientCursor::aboutToDelete(dl);
unindexRecord(d, todelete, dl, noWarn);
_deleteRecord(d, ns, todelete, dl);
NamespaceDetailsTransient::get_w( ns ).notifyOfWriteOp();
}
/** Note: if the object shrinks a lot, we don't free up space, we leave extra at end of the record.
*/
const DiskLoc DataFileMgr::updateRecord(
const char *ns,
NamespaceDetails *d,
NamespaceDetailsTransient *nsdt,
Record *toupdate, const DiskLoc& dl,
const char *_buf, int _len, OpDebug& debug, bool god)
{
StringBuilder& ss = debug.str;
dassert( toupdate == dl.rec() );
BSONObj objOld(toupdate);
BSONObj objNew(_buf);
DEV assert( objNew.objsize() == _len );
DEV assert( objNew.objdata() == _buf );
if( !objNew.hasElement("_id") && objOld.hasElement("_id") ) {
/* add back the old _id value if the update removes it. Note this implementation is slow
(copies entire object multiple times), but this shouldn't happen often, so going for simple
code, not speed.
*/
BSONObjBuilder b;
BSONElement e;
assert( objOld.getObjectID(e) );
b.append(e); // put _id first, for best performance
b.appendElements(objNew);
objNew = b.obj();
}
/* duplicate key check. we descend the btree twice - once for this check, and once for the actual inserts, further
below. that is suboptimal, but it's pretty complicated to do it the other way without rollbacks...
*/
vector<IndexChanges> changes;
bool changedId = false;
getIndexChanges(changes, *d, objNew, objOld, changedId);
uassert( 13596 , str::stream() << "cannot change _id of a document old:" << objOld << " new:" << objNew , ! changedId );
dupCheck(changes, *d, dl);
if ( toupdate->netLength() < objNew.objsize() ) {
// doesn't fit. reallocate -----------------------------------------------------
uassert( 10003 , "failing update: objects in a capped ns cannot grow", !(d && d->capped));
d->paddingTooSmall();
if ( cc().database()->profile )
ss << " moved ";
deleteRecord(ns, toupdate, dl);
return insert(ns, objNew.objdata(), objNew.objsize(), god);
}
nsdt->notifyOfWriteOp();
d->paddingFits();
/* have any index keys changed? */
{
unsigned keyUpdates = 0;
int z = d->nIndexesBeingBuilt();
for ( int x = 0; x < z; x++ ) {
IndexDetails& idx = d->idx(x);
for ( unsigned i = 0; i < changes[x].removed.size(); i++ ) {
try {
idx.head.btree()->unindex(idx.head, idx, *changes[x].removed[i], dl);
}
catch (AssertionException&) {
ss << " exception update unindex ";
problem() << " caught assertion update unindex " << idx.indexNamespace() << endl;
}
}
assert( !dl.isNull() );
BSONObj idxKey = idx.info.obj().getObjectField("key");
Ordering ordering = Ordering::make(idxKey);
keyUpdates += changes[x].added.size();