C FFI

C FFI

The ffi feature exposes a C ABI documented in ycallr.h (generated by cbindgen in CI).

Build

cargo build --features ffi

Regenerate the header:

cargo build --features ffi
cbindgen --crate ycallr-core -l c -o ycallr.h

Main entry points

Symbol	Purpose
ycallr_parse_yaml	Parse YAML at compile or debug time
ycallr_install_yaml_file	Install profile from YAML path
ycallr_load_installed	Load installed .pb by name
ycallr_parse_proto	Load from protobuf bytes
ycallr_client_new	Create HTTP client
ycallr_call	Execute command
ycallr_set_base_url	Override base URL at runtime
ycallr_get_last_error	Thread-local error string

Error handling

Functions return null or negative codes on failure. Read ycallr_get_last_error() for details.

Strings returned by the API must be freed with ycallr_string_free when documented as owned.

Safe helpers (Rust)

c_string_to_str(ptr) decodes NUL-terminated FFI return pointers into Option<String> without exposing raw pointer rules to callers.

Consumers

• ycallr-cli (thin FFI frontend)
• C, Go, Python, or other languages via the same header

The CLI does not call YcallrClient directly; it only uses symbols from ycallr.h.