Generate FFI bindings for R's C API

Parses R's header files (Rinternals.h, R.h, Rmath.h) and generates R bindings that allow calling R's internal C functions directly via FFI.

Usage

bindgen_r_api(
  output_file = NULL,
  headers = c("Rinternals.h", "R.h", "Rmath.h"),
  include_path = R.home("include"),
  load_r_lib = .is_windows,
  verbose = FALSE
)

Arguments

output_file

Path to write the generated R bindings. If NULL, returns the parsed results without writing.

headers

Character vector of header names to parse. Default includes "Rinternals.h", "R.h", and "Rmath.h".

include_path

Path to R's include directory. Defaults to R.home("include").

load_r_lib

Logical. If TRUE (default on Windows), attempt to load the R shared library to ensure symbols are available.

verbose

Logical. If TRUE, print progress messages.

Value

Invisibly returns a list with parsed results for each header:

structs

Named list of struct definitions

functions

Named list of function signatures

typedefs

Named list of typedef mappings

enums

Named list of enum definitions

Details

On Unix-like systems (Linux, macOS), R's symbols are typically available in the running process. On Windows, the R.dll may need to be explicitly loaded. Set load_r_lib = TRUE to handle this automatically.

The generated bindings create wrapper functions that use ffi_function() to call the underlying C functions. Each wrapper includes roxygen2 documentation with parameter types and return values.

Available Headers

Rinternals.h

Core R internals: SEXP manipulation, memory management, type checking functions (Rf_isInteger, Rf_length, etc.)

R.h

Main R header, includes standard utilities

Rmath.h

Statistical distribution functions (dnorm, pnorm, qnorm, gamma, beta, etc.)

See also

ffi_parse_header(), generate_r_bindings(), ffi_function()

Examples

if (FALSE) { # \dontrun{
# Generate bindings to a file
bindgen_r_api(output_file = "r_api_bindings.R")

# Parse without writing (for inspection)
result <- bindgen_r_api(verbose = TRUE)
names(result$Rinternals$functions)

# Generate only Rmath bindings
bindgen_r_api(
    output_file = "rmath_bindings.R",
    headers = "Rmath.h"
)

# After sourcing generated bindings:
# source("r_api_bindings.R")
# r_Rf_dnorm4(0, 0, 1, 0L)  # same as dnorm(0, 0, 1)
} # }