Clang.jl provides a Julia language wrapper for libclang: the stable, C-exported interface to (a subset of) the LLVM Clang compiler. The libclang API documentation provides background on the functionality available through libclang, and thus through the Julia wrapper. The Clang.jl repository also hosts related tools built on top of libclang functionality.
Installation requirements are listed down page.
Parsing C with Clang and Julia
Clang.jl includes a generator to create Julia wrappers for C libraries from a collection of header files. The following declarations are currently supported:
-
function: translated to Julia ccall, with full type translation
-
typedef: translated to Julia typealias to underlying intrinsic type
-
enum: translated to const value symbol
-
struct: partial struct support may be enabled by setting WrapContext.options.wrap_structs = true
- note: struct support is limited to intrinsic types. Unsupported constructs presently include: nested structs and unions, as well as fixed-size arrays.
Please see the following repositories for examples of the wrapper driver scripts and generator output:
- Sundials.jl: interface to the LLNL "SUite of Nonlinear and DIfferential/ALgebraic equation Solvers" package
- libCURL.jl: wrapper of cURL
libclang and libclang-dev (versions >= 3.1) are required. libclang may
optionally be built by the Julia build system by setting
BUILD_LLVM_CLANG=1 in julia/Make.user.
When using a distribution packaged version, note the latest version may only be available from an optional pre-release archive (e.g. Ubuntu PPA).
To install using the Julia package manager, use: Pkg.add("Clang"). You can use an external LLVM/Clang to build Clang.jl by specifying a llvm-config:
ENV["LLVM_CONFIG"]="/usr/lib/llvm-3.3/bin/llvm-config"
Pkg.add("Clang")
The cindex.jl libclang wrapper encompasses most CXType, CXCursor, and C++ related functions. A small convenience API is provided for basic tasks related to index generation, and retrieval of cursor kind and type information.
All testing and development so far has been on Ubuntu 12.04.1 (64-bit)
using Clang.cindex
julia> topcu = cindex.parse("Index.h") # Parse Index.h, returning the root cursor
julia> topcl = children(topcu)
julia> topcl.size
595
julia> cu = topcl[350]
julia> cu_kind(cu) == CIndex.CurKind.FUNCTIONDECL
true
julia> name(topcl[350])
"clang_parseTranslationUnit(CXIndex, const char *, const char *const *, int, struct CXUnsavedFile *, unsigned int, unsigned int)"See the examples/ and util/ folders for further usage scenarios. Clang.jl is partially self-generating, including parsing of the enums (util/genCIndex_h.jl)
There is a small convenience API exported by CIndex:
tu_init # init and parse file to TranslationUnit
tu_cursor # get top cursor from TranslationUnit
children # gets CXCursor children; accessed by ref.
cu_kind # CIndex.CurKind enum
ty_kind # CIndex.TypKind enum
name # get the DisplayName of a CXCursor
spelling # get spelling of a CXCursor or CXType
cu_file # file in which cursor was declared
is_function # CXCursor or CXType
is_null # CXCursor
For documentation of wrapped CIndex functions, see:
http://clang.llvm.org/doxygen/group__CINDEX.html
For a nice introduction to some capabilities and limitations (fewer now) of the libclang API, see this post:
http://eli.thegreenplace.net/2011/07/03/parsing-c-in-python-with-clang/
Most libclang functions accept and return small structs by value. As Julia does not (yet) have full struct support, the current Clang.jl implementation includes a C++ wrapper. clang functions are wrapped by a C++ function that memcpys data to/from a Julia-owned memory array (passed by pointer)
see src/cindex_base.jl and deps/src/wrapclang.h for generated wrappers.
Some functions are manually wrapped for convenience and ease of implementation, or to provide a more Julia-friendly API.
see src/Clang.jl and deps/src/wrapclang.cpp
Clang.jl is licensed under the MIT license.