Sealang (fork of pybee/sealang)

Sealang is a fork of the official Python 3 bindings for libclang, patched for proper handling of literals and operators.

Installation

To compile Sealang, you'll need to:

1. Make sure you have Python >= 3.7

2. Install LLVM 11.0 (with clang)

   Note about Windows: You might need to compile the project. Follow the steps here to compile it (You must enable the clang project)

3. Set the environment variable LLVM_HOME to the root of the compiled LLVM project
4. pip install git+https://github.com/gtors/sealang#egg=sealang-11.0

Usage

Sealang provides a superset of the functionality provided by libclang. Those features are:

• Cursor objects have 4 additional attributes:
  • literal - the value of a literal expression. Available on IntegerLiteral, FloatingLiteral, StringLiteral, CharacterLiteral, and CXXBooleanLiteral nodes.
  • operator - the printable version of an operator. Only available on BinaryOperator, UnaryOperator, and CompoundAssignOperator cursor nodes.
  • binary_operator - an enumeration value describing a BinaryOperator or CompoundAssignOperator node.
  • unary_operator - an enumeration value describing a UnaryOperator node.
• BinaryOperator - An enumeration for the types of binary operators:
  • BinaryOperator.INVALID
  • BinaryOperator.PTRMEMD
  • BinaryOperator.PTRMEMI
  • BinaryOperator.MUL
  • BinaryOperator.DIV
  • BinaryOperator.REM
  • BinaryOperator.ADD
  • BinaryOperator.SUB
  • BinaryOperator.SHL
  • BinaryOperator.SHR
  • BinaryOperator.LT
  • BinaryOperator.GT
  • BinaryOperator.LE
  • BinaryOperator.GE
  • BinaryOperator.EQ
  • BinaryOperator.NE
  • BinaryOperator.AND
  • BinaryOperator.XOR
  • BinaryOperator.OR
  • BinaryOperator.LAND
  • BinaryOperator.LOR
  • BinaryOperator.ASSIGN
  • BinaryOperator.MULASSIGN
  • BinaryOperator.DIVASSIGN
  • BinaryOperator.REMASSIGN
  • BinaryOperator.ADDASSIGN
  • BinaryOperator.SUBASSIGN
  • BinaryOperator.SHLASSIGN
  • BinaryOperator.SHRASSIGN
  • BinaryOperator.ANDASSIGN
  • BinaryOperator.XORASSIGN
  • BinaryOperator.ORASSIGN
  • BinaryOperator.COMMA
  • BinaryOperator.UNKNOWN
• UnaryOperator - An enumeration for the types of binary operators:
  • UnaryOperator.INVALID
  • UnaryOperator.POSTINC
  • UnaryOperator.POSTDEC
  • UnaryOperator.PREINC
  • UnaryOperator.PREDEC
  • UnaryOperator.ADDROF
  • UnaryOperator.DEREF
  • UnaryOperator.PLUS
  • UnaryOperator.MINUS
  • UnaryOperator.NOT
  • UnaryOperator.LNOT
  • UnaryOperator.REAL
  • UnaryOperator.IMAG
  • UnaryOperator.EXTENSION
  • UnaryOperator.UNKNOWN

How it works

Sealang is a bit of a nasty hack. libclang is a set of C bindings to a C++ API; Python ctypes are then used to wrap the C API. However, while the C++ API is quite rich, libclang is less so.

Sealang bridges this gap by providing C wrappers around the C++ calls that provide the useful functionality. This library of C functions is wrapped up as a Python C module for delivery purposes - this C module contains no exposed Python objects or methods, but because it's a module, the underlying compiled sealang.so file is easy to find. ctypes are then used to expose the sealang wrapper functions;

Internally, Sealang reproduces some minor pieces of the libclang API; these are methods (such as the string creation and manipulation methods) that aren't exposed as symbols for third-party use.

Relationship to Clang

This project aims to mirror what is currently available in the Python bindings to libclang. The version number for this project is drawn from the version of the official clang repository.

Any changes made upstream to libclang will be mirrored here.

Contributing

If you experience problems with Sealang, log them on GitHub. If you want to contribute code, please fork the code and submit a pull request.