void FileAllocator::ensureLength(int fd , long size) {
#if !defined(_WIN32)
if (useSparseFiles(fd)) {
LOG(1) << "using ftruncate to create a sparse file" << endl;
int ret = ftruncate(fd, size);
uassert(16063, "ftruncate failed: " + errnoWithDescription(), ret == 0);
return;
}
#endif
#if defined(__linux__)
int ret = posix_fallocate(fd,0,size);
if ( ret == 0 )
return;
log() << "FileAllocator: posix_fallocate failed: " << errnoWithDescription( ret ) << " falling back" << endl;
#endif
off_t filelen = lseek( fd, 0, SEEK_END );
if ( filelen < size ) {
if (filelen != 0) {
stringstream ss;
ss << "failure creating new datafile; lseek failed for fd " << fd << " with errno: " << errnoWithDescription();
uassert( 10440 , ss.str(), filelen == 0 );
}
// Check for end of disk.
uassert( 10441 , str::stream() << "Unable to allocate new file of size " << size << ' ' << errnoWithDescription(),
size - 1 == lseek(fd, size - 1, SEEK_SET) );
uassert( 10442 , str::stream() << "Unable to allocate new file of size " << size << ' ' << errnoWithDescription(),
1 == write(fd, "", 1) );
// File expansion is completed here. Do not do the zeroing out on OS-es where there
// is no risk of triggering allocation-related bugs such as
// http://support.microsoft.com/kb/2731284.
//
if (!ProcessInfo::isDataFileZeroingNeeded()) {
return;
}
lseek(fd, 0, SEEK_SET);
const long z = 256 * 1024;
const boost::scoped_array<char> buf_holder (new char[z]);
char* buf = buf_holder.get();
memset(buf, 0, z);
long left = size;
while ( left > 0 ) {
long towrite = left;
if ( towrite > z )
towrite = z;
int written = write( fd , buf , towrite );
uassert( 10443 , errnoWithPrefix("FileAllocator: file write failed" ), written > 0 );
left -= written;
}
}
}
void FileAllocator::ensureLength(int fd , long size) {
#if !defined(_WIN32)
if (useSparseFiles(fd)) {
LOG(1) << "using ftruncate to create a sparse file" << endl;
int ret = ftruncate(fd, size);
uassert(16063, "ftruncate failed: " + errnoWithDescription(), ret == 0);
return;
}
#endif
#if defined(__linux__)
int ret = posix_fallocate(fd,0,size);
if ( ret == 0 )
return;
log() << "FileAllocator: posix_fallocate failed: " << errnoWithDescription( ret ) << " falling back" << endl;
#endif
off_t filelen = lseek( fd, 0, SEEK_END );
if ( filelen < size ) {
if (filelen != 0) {
stringstream ss;
ss << "failure creating new datafile; lseek failed for fd " << fd << " with errno: " << errnoWithDescription();
uassert( 10440 , ss.str(), filelen == 0 );
}
// Check for end of disk.
uassert( 10441 , str::stream() << "Unable to allocate new file of size " << size << ' ' << errnoWithDescription(),
size - 1 == lseek(fd, size - 1, SEEK_SET) );
uassert( 10442 , str::stream() << "Unable to allocate new file of size " << size << ' ' << errnoWithDescription(),
1 == write(fd, "", 1) );
lseek(fd, 0, SEEK_SET);
const long z = 256 * 1024;
const boost::scoped_array<char> buf_holder (new char[z]);
char* buf = buf_holder.get();
memset(buf, 0, z);
long left = size;
while ( left > 0 ) {
long towrite = left;
if ( towrite > z )
towrite = z;
int written = write( fd , buf , towrite );
uassert( 10443 , errnoWithPrefix("FileAllocator: file write failed" ), written > 0 );
left -= written;
}
}
}
