Noise

Building & Testing

git clone https://github.com/ervanalb/noise
cd nzlib
make
cd ..
make

LD_LIBRARY_PATH=.:nzlib ./noise_test_unison

cd ui
LD_LIBRARY_PATH=.. python3 ui.py

Typesystem

• typedef void nz_obj; -- nz_obj represents an object/value that is part of the typesystem. You don't get type checking in C, though :(

See src/types.md.

Blocks & Graphs

• nz_obj * NZ_PULL(struct nz_block self, int port_index, nz_obj * result); -- returns NULL on failure, result on success.

  • The caller owns result and needs to ensure that there is enough memory allocated to hold the result.
  • Types are checked at connect-time, not pull-time. There is no type checking in the C code (sadly...)

• struct nz_context keeps track of the available typeclasses & blockclasses. These can be loaded at runtime from a shared library. Currently there is only the standard library, nzlib.

Conventions

Little conventions that are used that make the code easier to follow. Break them when appropriate.

• If using noise as a library, you only need to #include "libnoise.h".
• All extern symbols are prefixed with nz_ to facilitate including as a library.
• An rsprintf function is used to allocate memory for a formatted string (like asprintf, with a strdup-like API)
• Error handling
  • If a function can error, it will return an nz_rc, which is typedef'd to int.
  • On success, it will return 0 / NZ_SUCCESS. On failure it will return a (positive) error code
    • Error codes defined in noise.h
  • (Functions which test something and return a boolean will return 0 for false, and 1 for true!)
• Carefully document when pointer ownership transfers! It should be very obvious from signature/name.
• OOP-y data:
  • Preference for nz_rc xxx_init(struct xxx *, ...) and void xxx_term(struct xxx *) functions, which initialize & deinitialize an already-allocated struct.
  • For opaque structs, use struct xxx * xxx_create(...) and void xxx_destroy(struct xxx *) functions.
  • structs have members in the form struct nz_xxx { int xxx_yyy; ... } to make code infinitely more greppable
• Dealing with pointers to structs is nice, but so is having them on the stack. struct xxx x[1]; solves this, making x be accessible as (almost) a struct xxx *.