Style changes:
- use std algorithm for some stringOps internals
- pass SubStrings iterators by const reference
ENH: special nullptr handling for ISstream getLine
- pass through to istream::ignore to support read and discard
- avoid stealing autoPtr in interpolationTable copy operations
- improve local memory requirements of readers
- make OpenFOAM table reader default constructible
- more code alignment between csvTableReader and Function1::CSV
(fix#1498 for csvTableReader as well)
- now indicate that the dictionary entry is missing, not that it is
an unknown function type.
STYLE: adjust PatchFunction1New.C to have logic structure look similar
- makes the intent clearer and avoids the need for additional
constructor casting. Eg,
labelList(10, Zero) vs. labelList(10, 0)
scalarField(10, Zero) vs. scalarField(10, scalar(0))
vectorField(10, Zero) vs. vectorField(10, vector::zero)
- more dictionary-like methods, enforce keyType::LITERAL for all
lookups to avoid any spurious keyword matching.
- new readEntry, readIfPresent methods
- The get() method replaces the now deprecate lookup() method.
- Deprecate lookupOrFailsafe()
Failsafe behaviour is now an optional parameter for lookupOrDefault,
which makes it easier to tailor behaviour at runtime.
- output of the names is now always flatted without line-breaks.
Thus,
os << flatOutput(someEnumNames.names()) << nl;
os << someEnumNames << nl;
both generate the same output.
- Constructor now uses C-string (const char*) directly instead of
Foam::word in its initializer_list.
- Remove special enum + initializer_list constructor form since
it can create unbounded lookup indices.
- Removd old hasEnum, hasName forms that were provided during initial
transition from NamedEnum.
- Added static_assert on Enum contents to restrict to enum or
integral values. Should not likely be using this class to enumerate
other things since it internally uses an 'int' for its values.
Changed volumeType accordingly to enumerate on its type (enum),
not the class itself.
- use keyType::option enum to consolidate searching options.
These enumeration names should be more intuitive to use
and improve code readability.
Eg, lookupEntry(key, keyType::REGEX);
vs lookupEntry(key, false, true);
or
Eg, lookupEntry(key, keyType::LITERAL_RECURSIVE);
vs lookupEntry(key, true, false);
- new findEntry(), findDict(), findScoped() methods with consolidated
search options for shorter naming and access names more closely
aligned with other components. Behave simliarly to the
methods lookupEntryPtr(), subDictPtr(), lookupScopedEntryPtr(),
respectively. Default search parameters consistent with lookupEntry().
Eg, const entry* e = dict.findEntry(key);
vs const entry* e = dict.lookupEntryPtr(key, false, true);
- added '*' and '->' dereference operators to dictionary searchers.
- use the dictionary 'get' methods instead of readScalar for
additional checking
Unchecked: readScalar(dict.lookup("key"));
Checked: dict.get<scalar>("key");
- In templated classes that also inherit from a dictionary, an additional
'template' keyword will be required. Eg,
this->coeffsDict().template get<scalar>("key");
For this common use case, the predefined getXXX shortcuts may be
useful. Eg,
this->coeffsDict().getScalar("key");
- instead of dict.lookup(name) >> val;
can use dict.readEntry(name, val);
for checking of input token sizes.
This helps catch certain types of input errors:
{
key1 ; // <- Missing value
key2 1234 // <- Missing ';' terminator
key3 val;
}
STYLE: readIfPresent() instead of 'if found ...' in a few more places.
- Always used for optional dictionary entries, since these are individual
values, and not meant to be embedded in a larger stream of tokens.
Methods:
- lookupOrDefault, lookupOrAddDefault, lookupOrDefaultCompat
- readIfPresent, readIfPresentCompat
- Handling mandatory dictionary entries is slightly more complex,
since these may be part of larger stream of tokens, and are often
used in a constructor context. For example,
word modelType(dict.lookup("type"));
Or they are used without a definite context. For example,
dict.lookup("format") >> outputFormat;
Newly introduced methods for mandatory dictionary entries:
- get, getCompat
- read, readCompat
In a constructor or assignment context:
word modelType(dict.get<word>("type"));
outputFormat = dict.lookup("format");
without copy/move (similar to readIfPresent):
dict.read("format", outputFormat);
- both autoPtr and tmp are defined with an implicit construct from
nullptr (but with explicit construct from a pointer to null).
Thus is it safe to use 'nullptr' when returning an empty autoPtr or tmp.
Improve alignment of its behaviour with std::shared_ptr
- element_type typedef
- swap, reset methods
* additional reference access methods:
cref()
returns a const reference, synonymous with operator().
This provides a more verbose alternative to using the '()' operator
when that is desired.
Mnemonic: a const form of 'ref()'
constCast()
returns a non-const reference, regardless if the underlying object
itself is a managed pointer or a const object.
This is similar to ref(), but more permissive.
Mnemonic: const_cast<>
Using the constCast() method greatly reduces the amount of typing
and reading. And since the data type is already defined via the tmp
template parameter, the type deduction is automatically known.
Previously,
const tmp<volScalarField>& tfld;
const_cast<volScalarField&>(tfld()).rename("name");
volScalarField& fld = const_cast<volScalarField&>(tfld());
Now,
tfld.constCast().rename("name");
auto& fld = tfld.constCast();
--
BUG: attempts to move tmp value that may still be shared.
- old code simply checked isTmp() to decide if the contents could be
transfered. However, this means that the content of a shared tmp
would be removed, leaving other instances without content.
* movable() method checks that for a non-null temporary that is
unique (not shared).
Improve alignment of its behaviour with std::unique_ptr
- element_type typedef
- release() method - identical to ptr() method
- get() method to get the pointer without checking and without releasing it.
- operator*() for dereferencing
Method name changes
- renamed rawPtr() to get()
- renamed rawRef() to ref(), removed unused const version.
Removed methods/operators
- assignment from a raw pointer was deleted (was rarely used).
Can be convenient, but uncontrolled and potentially unsafe.
Do allow assignment from a literal nullptr though, since this
can never leak (and also corresponds to the unique_ptr API).
Additional methods
- clone() method: forwards to the clone() method of the underlying
data object with argument forwarding.
- reset(autoPtr&&) as an alternative to operator=(autoPtr&&)
STYLE: avoid implicit conversion from autoPtr to object type in many places
- existing implementation has the following:
operator const T&() const { return operator*(); }
which means that the following code works:
autoPtr<mapPolyMesh> map = ...;
updateMesh(*map); // OK: explicit dereferencing
updateMesh(map()); // OK: explicit dereferencing
updateMesh(map); // OK: implicit dereferencing
for clarity it may preferable to avoid the implicit dereferencing
- prefer operator* to operator() when deferenced a return value
so it is clearer that a pointer is involve and not a function call
etc Eg, return *meshPtr_; vs. return meshPtr_();
Temporal variation of Ta is generally more useful than spatial variation but
a run-time switch between the two modes of operation could be implemented in
needed.
Original commit message:
------------------------
Parallel IO: New collated file format
When an OpenFOAM simulation runs in parallel, the data for decomposed fields and
mesh(es) has historically been stored in multiple files within separate
directories for each processor. Processor directories are named 'processorN',
where N is the processor number.
This commit introduces an alternative "collated" file format where the data for
each decomposed field (and mesh) is collated into a single file, which is
written and read on the master processor. The files are stored in a single
directory named 'processors'.
The new format produces significantly fewer files - one per field, instead of N
per field. For large parallel cases, this avoids the restriction on the number
of open files imposed by the operating system limits.
The file writing can be threaded allowing the simulation to continue running
while the data is being written to file. NFS (Network File System) is not
needed when using the the collated format and additionally, there is an option
to run without NFS with the original uncollated approach, known as
"masterUncollated".
The controls for the file handling are in the OptimisationSwitches of
etc/controlDict:
OptimisationSwitches
{
...
//- Parallel IO file handler
// uncollated (default), collated or masterUncollated
fileHandler uncollated;
//- collated: thread buffer size for queued file writes.
// If set to 0 or not sufficient for the file size threading is not used.
// Default: 2e9
maxThreadFileBufferSize 2e9;
//- masterUncollated: non-blocking buffer size.
// If the file exceeds this buffer size scheduled transfer is used.
// Default: 2e9
maxMasterFileBufferSize 2e9;
}
When using the collated file handling, memory is allocated for the data in the
thread. maxThreadFileBufferSize sets the maximum size of memory in bytes that
is allocated. If the data exceeds this size, the write does not use threading.
When using the masterUncollated file handling, non-blocking MPI communication
requires a sufficiently large memory buffer on the master node.
maxMasterFileBufferSize sets the maximum size in bytes of the buffer. If the
data exceeds this size, the system uses scheduled communication.
The installation defaults for the fileHandler choice, maxThreadFileBufferSize
and maxMasterFileBufferSize (set in etc/controlDict) can be over-ridden within
the case controlDict file, like other parameters. Additionally the fileHandler
can be set by:
- the "-fileHandler" command line argument;
- a FOAM_FILEHANDLER environment variable.
A foamFormatConvert utility allows users to convert files between the collated
and uncollated formats, e.g.
mpirun -np 2 foamFormatConvert -parallel -fileHandler uncollated
An example case demonstrating the file handling methods is provided in:
$FOAM_TUTORIALS/IO/fileHandling
The work was undertaken by Mattijs Janssens, in collaboration with Henry Weller.
