/** caller handles locking */
static bool PREPLOGBUFFER(AlignedBuilder& bb) {
bb.reset();
unsigned *lenInBlockHeader;
{
// JSectHeader
bb.appendStr("\nHH\n", false);
lenInBlockHeader = (unsigned *) bb.skip(4);
}
string lastFilePath;
{
scoped_lock lk(privateViews._mutex());
for( vector<WriteIntent>::iterator i = wi._writes.begin(); i != wi._writes.end(); i++ ) {
size_t ofs;
MongoMMF *mmf = privateViews._find(i->p, ofs);
if( mmf == 0 ) {
journalingFailure("view pointer cannot be resolved");
}
else {
if( !mmf->dirty() )
mmf->dirty() = true; // usually it will already be dirty so don't bother writing then
{
size_t ofs = ((char *)i->p) - ((char*)mmf->getView().p);
i->w_ptr = ((char*)mmf->view_write()) + ofs;
}
if( mmf->filePath() != lastFilePath ) {
lastFilePath = mmf->filePath();
JDbContext c;
bb.appendStruct(c);
bb.appendStr(lastFilePath);
}
JEntry e;
e.len = i->len;
e.fileNo = mmf->fileSuffixNo();
bb.appendStruct(e);
bb.appendBuf(i->p, i->len);
}
}
}
{
JSectFooter f;
f.hash = 0;
bb.appendStruct(f);
}
{
unsigned L = (bb.len() + 8191) & 0xffffe000; // fill to alignment
dassert( L >= (unsigned) bb.len() );
*lenInBlockHeader = L;
unsigned padding = L - bb.len();
bb.skip(padding);
dassert( bb.len() % 8192 == 0 );
}
return true;
}
/** caller handles locking */
static bool PREPLOGBUFFER(BufBuilder& bb) {
if( writes.empty() )
return false;
bb.reset();
unsigned *lenInBlockHeader;
{
// JSectHeader
bb.appendStr("\nHH\n", false);
lenInBlockHeader = (unsigned *) bb.skip(4);
}
string lastFilePath;
{
scoped_lock lk(privateViews._mutex());
for( vector<WriteIntent>::iterator i = writes.begin(); i != writes.end(); i++ ) {
size_t ofs;
MongoMMF *mmf = privateViews._find(i->p, ofs);
if( mmf == 0 ) {
journalingFailure("view pointer cannot be resolved");
}
else {
if( mmf->filePath() != lastFilePath ) {
lastFilePath = mmf->filePath();
JDbContext c;
bb.appendStruct(c);
bb.appendStr(lastFilePath);
}
JEntry e;
e.len = i->len;
e.fileNo = mmf->fileSuffixNo();
bb.appendStruct(e);
bb.appendBuf(i->p, i->len);
}
}
}
{
JSectFooter f;
f.hash = 0;
bb.appendStruct(f);
}
{
unsigned L = (bb.len() + 8191) & 0xffffe000; // fill to alignment
dassert( L >= (unsigned) bb.len() );
*lenInBlockHeader = L;
unsigned padding = L - bb.len();
bb.skip(padding);
dassert( bb.len() % 8192 == 0 );
}
writes.clear();
alreadyNoted.clear();
return true;
}
/** we will build an output buffer ourself and then use O_DIRECT
we could be in read lock for this
caller handles locking
*/
static void PREPLOGBUFFER() {
assert( cmdLine.dur );
AlignedBuilder& bb = commitJob._ab;
bb.reset();
unsigned lenOfs;
// JSectHeader
{
bb.appendStr("\nHH\n", false);
lenOfs = bb.skip(4);
}
// ops other than basic writes
{
for( vector< shared_ptr<DurOp> >::iterator i = commitJob.ops().begin(); i != commitJob.ops().end(); ++i ) {
(*i)->serialize(bb);
}
}
// write intents
{
scoped_lock lk(privateViews._mutex());
string lastFilePath;
for( vector<WriteIntent>::iterator i = commitJob.writes().begin(); i != commitJob.writes().end(); i++ ) {
size_t ofs;
MongoMMF *mmf = privateViews._find(i->p, ofs);
if( mmf == 0 ) {
string s = str::stream() << "view pointer cannot be resolved " << (size_t) i->p;
journalingFailure(s.c_str()); // asserts
return;
}
if( !mmf->willNeedRemap() ) {
mmf->willNeedRemap() = true; // usually it will already be dirty so don't bother writing then
}
//size_t ofs = ((char *)i->p) - ((char*)mmf->getView().p);
i->w_ptr = ((char*)mmf->view_write()) + ofs;
if( mmf->filePath() != lastFilePath ) {
lastFilePath = mmf->filePath();
JDbContext c;
bb.appendStruct(c);
bb.appendStr(lastFilePath);
}
JEntry e;
e.len = i->len;
assert( ofs <= 0x80000000 );
e.ofs = (unsigned) ofs;
e.fileNo = mmf->fileSuffixNo();
bb.appendStruct(e);
bb.appendBuf(i->p, i->len);
}
}
{
JSectFooter f(bb.buf(), bb.len());
bb.appendStruct(f);
}
{
assert( 0xffffe000 == (~(Alignment-1)) );
unsigned L = (bb.len() + Alignment-1) & (~(Alignment-1)); // fill to alignment
dassert( L >= (unsigned) bb.len() );
*((unsigned*)bb.atOfs(lenOfs)) = L;
unsigned padding = L - bb.len();
bb.skip(padding);
dassert( bb.len() % Alignment == 0 );
}
return;
}