From cfa58e08195b881f60a6bdffda0d530a55affa83 Mon Sep 17 00:00:00 2001
From: mattijs <mattijs>
Date: Mon, 21 Feb 2011 11:25:13 +0000
Subject: [PATCH] ENH: codeStream: documentation
---
ReleaseNotes-dev | 39 ++++++
doc/changes/onTheFly.txt | 122 ++++++++++++++++++
src/OpenFOAM/db/IOstreams/Sstreams/ISstream.C | 2 +-
.../codedFixedValueFvPatchScalarField.C | 2 +-
4 files changed, 163 insertions(+), 2 deletions(-)
create mode 100644 doc/changes/onTheFly.txt
diff --git a/ReleaseNotes-dev b/ReleaseNotes-dev
index 230a1168263..06a9bb7c776 100644
--- a/ReleaseNotes-dev
+++ b/ReleaseNotes-dev
@@ -134,6 +134,28 @@
+ single integer reduction instead of one reduction per monitored file.
+ only files that can be re-read are being checked. Drastic reduction of
number of files to check.
+*** *New* #codeStream dictionary entry method. Uses on-the-fly compilation
+ of OpenFOAM C++ code to construct dictionary.
+ E.g. in blockMeshDict:
+
+ convertToMeters 0.001;
+
+ vertices #codeStream
+ {
+ code
+ #{
+ label nVerts =
+ readLabel(dict.lookup("nx"))
+ * readLabel(dict.lookup("ny"))
+ * readLabel(dict.lookup("nz"));
+ pointField verts(nVerts);
+ // Now fill verts here
+ // ..
+ os << verts;
+ #};
+ }
+ See also doc/changes/onTheFly.txt
+
* Solvers
A number of new solvers have been developed for a range of engineering
applications. There has been a set of improvements to certain classes of
@@ -163,6 +185,23 @@
+ takes optional fieldName to sample
+ directMapped patch added 'normal' method to calculate sample points
to e.g. sample fields just above wall (e.g. for streaklines)
+ + *New* codedFixedValue: Uses the on-the-fly code compilation from #codeStream
+ to provide an in-line fixedValueFvPatchScalarField. E.g.
+
+ outlet
+ {
+ type codedFixedValue;
+ value uniform 0;
+ redirectType fixedValue10;
+
+ code
+ #{
+ operator==(min(10, 0.1*this->db().time().value()));
+ #};
+ }
+
+ See doc/changes/onTheFly.txt
+
* Utilities
There have been some utilities added and updated in this release.
*** *New* utilities
diff --git a/doc/changes/onTheFly.txt b/doc/changes/onTheFly.txt
new file mode 100644
index 00000000000..51665755aa4
--- /dev/null
+++ b/doc/changes/onTheFly.txt
@@ -0,0 +1,122 @@
+On-the-fly code compilation
+---------------------------
+
+1. #codeStream
+This is a dictionary preprocessing directive ('functionEntry') which provides
+a snippet of OpenFOAM
+C++ code which gets compiled and executed to provide the actual dictionary
+entry. The snippet gets provided as three sections of C++ code which just gets
+inserted into a template:
+- 'code' section: the actual body of the code. It gets called with
+ arguments
+
+ const dictionary& dict,
+ OStream& os
+
+ and the C++ code can do a dict.lookup to find current dictionary values.
+
+- optional 'codeInclude' section: any #include statements to include
+OpenFOAM files.
+
+- optional 'codeOptions' section: any extra compilation flags to be added to
+EXE_INC in Make/options
+
+To ease inputting mulit-line code there is the #{ #} syntax. Anything
+inbetween these two delimiters becomes a string with all newlines, quotes etc
+preserved.
+
+Example: Look up dictionary entries and do some calculation
+
+ startTime 0;
+ endTime 100;
+ ..
+ writeInterval #codeStream
+ {
+ code
+ #{
+ scalar start = readScalar(dict["startTime"]);
+ scalar end = readScalar(dict["endTime"]);
+ label nDumps = 5;
+ label interval = end-start
+ os << ((start-end)/nDumps)
+ #}
+ };
+
+
+
+2. Implementation
+- the #codeStream entry reads the dictionary following it, extracts the
+code, codeInclude, codeOptions sections (these are just strings) and
+calculates the SHA1 checksum of the contents.
+- it writes library source files to constant/codeStream/<sha1> and compiles it
+using 'wmake libso'.
+- the resulting library gets loaded (dlopen, dlsym) and the function
+executed
+- the function will have written its output into the Ostream which then
+gets used to construct the entry to replace the whole #codeStream section.
+- using the sha1 means that same code will only be compiled & loaded once.
+
+
+3. codedFixedValue
+This uses the code from codeStream to have an in-line specialised
+fixedValueFvPatchScalarField:
+
+ outlet
+ {
+ type codedFixedValue;
+ value uniform 0;
+ redirectType fixedValue10;
+
+ code
+ #{
+ operator==(min(10, 0.1*this->db().time().value()));
+ #};
+ }
+
+It by default always includes fvCFD.H and adds the finiteVolume library
+to the include search path.
+
+
+4. Security
+Allowing the case to execute C++ code does introduce security risks.
+A thirdparty case might have a #codeStream{#code system("rm -rf .");};
+hidden somewhere in a dictionary. #codeStream is therefore not enabled by
+default - you have to enable it by setting in the system-wide controlDict
+
+ InfoSwitches
+ {
+ // Allow case-supplied c++ code (#codeStream, codedFixedValue)
+ allowSystemOperations 1;
+ }
+
+
+5. Field manipulation.
+Fields are read in as IOdictionary so can be upcast to provide access to the
+mesh:
+
+internalField #codeStream
+{
+ codeInclude
+ #{
+ #include "fvCFD.H"
+ #};
+
+ code
+ #{
+ const IOdictionary& d = refCast<const IOdictionary&>(dict);
+ const fvMesh& mesh = refCast<const fvMesh>(d.db());
+ scalarField fld(mesh.nCells(), 0.0);
+ fld.writeEntry("", os);
+ #};
+
+ codeOptions
+ #{
+ -I$(LIB_SRC)/finiteVolume/lnInclude
+ #};
+};
+
+
+
+6. Other
+- the implementation is still a bit raw - it compiles code overly much
+- parallel running not tested a lot. What about distributed data parallel.
diff --git a/src/OpenFOAM/db/IOstreams/Sstreams/ISstream.C b/src/OpenFOAM/db/IOstreams/Sstreams/ISstream.C
index 6bbb130a49a..135f61823af 100644
--- a/src/OpenFOAM/db/IOstreams/Sstreams/ISstream.C
+++ b/src/OpenFOAM/db/IOstreams/Sstreams/ISstream.C
@@ -550,7 +550,7 @@ Foam::Istream& Foam::ISstream::read(string& str)
Foam::Istream& Foam::ISstream::readVerbatim(string& str)
{
- static const int maxLen = 1024;
+ static const int maxLen = 8000;
static const int errLen = 80; // truncate error message for readability
static char buf[maxLen];
diff --git a/src/finiteVolume/fields/fvPatchFields/derived/codedFixedValue/codedFixedValueFvPatchScalarField.C b/src/finiteVolume/fields/fvPatchFields/derived/codedFixedValue/codedFixedValueFvPatchScalarField.C
index 80a8096fa3e..388d013b553 100644
--- a/src/finiteVolume/fields/fvPatchFields/derived/codedFixedValue/codedFixedValueFvPatchScalarField.C
+++ b/src/finiteVolume/fields/fvPatchFields/derived/codedFixedValue/codedFixedValueFvPatchScalarField.C
@@ -165,7 +165,7 @@ void Foam::codedFixedValueFvPatchScalarField::updateLibrary()
}
const fileName dir =
- db().time().constantPath()/"codedFixedValue"/redirectType_;
+ db().time().constantPath()/"codeStream"/redirectType_;
//Info<< "dir:" << dir << endl;
const fileName libPath
--
GitLab