wickra/examples/c

Wickra — C / C++ examples

The Wickra C ABI is a single shared/static library plus a generated header (bindings/c/include/wickra.h). Any C-capable language links against the same artifact; these examples show the plain-C path.

Build the library

From the workspace root:

cargo build -p wickra-c --release

This produces, in target/release/:

Platform	Shared library	Link target
Linux	libwickra.so	-lwickra
macOS	libwickra.dylib	-lwickra
Windows (MSVC)	wickra.dll	wickra.dll.lib (import lib)

A static library (libwickra.a / wickra.lib) is emitted alongside.

Build and run the smoke example

With CMake (portable, used by CI)

cmake -S examples/c -B examples/c/build -DWICKRA_LIB_DIR="$PWD/target/release"
cmake --build examples/c/build
ctest --test-dir examples/c/build --output-on-failure

Directly with a compiler

# Linux / macOS
cc examples/c/smoke.c -I bindings/c/include -L target/release -lwickra -lm -o smoke
LD_LIBRARY_PATH=target/release ./smoke        # macOS: DYLD_LIBRARY_PATH

# Windows (MinGW gcc, linking the DLL directly)
gcc examples/c/smoke.c -I bindings/c/include target/release/wickra.dll -lm -o smoke.exe

Expected output:

OK: wickra C ABI smoke passed (SMA streaming + batch + reset + NULL-safety + free)

The examples

Example	What it does
smoke.c	Links the boundary and asserts SMA streaming / batch / reset / NULL-safety values.
streaming.c	Feeds a synthetic price series through SMA / EMA / RSI / MACD tick by tick.
backtest.c	Runs an indicator basket over an OHLCV CSV (defaults to the bundled daily dataset).
multi_timeframe.c	Resamples the bundled 1-minute CSV to 5m / 15m / 1h / 4h / 1d and prints indicators per timeframe.
parallel_assets.c	Serial vs OpenMP fan-out over a synthetic panel (one handle per asset), with speedup.
strategy_rsi_mean_reversion.c	Hourly RSI(14) mean-reversion with a PnL / Sharpe / max-drawdown summary.
strategy_macd_adx.c	Hourly MACD crossover gated by ADX(14) > 20.
strategy_bollinger_squeeze.c	Daily Bollinger-squeeze breakout with an ATR(14) stop.
fetch_btcusdt.c	Downloads BTCUSDT klines from the Binance REST API into examples/data/ (shells out to curl).
live_binance.c	Polls the Binance REST klines endpoint via curl and streams closed candles through RSI(14).
smoke.cpp	C++ RAII via wickra::Handle from wickra.hpp.

ctest builds and runs every example except fetch_btcusdt and live_binance, which reach the network and are built only — run those two by hand. The C ABI exposes only the indicators, not the wickra-data IO layer, so the examples read CSV (wickra_csv.h) and resample themselves; the network ones shell out to the system curl rather than adding an HTTP/TLS dependency.

Usage shape

Every indicator follows the same five-function pattern over an opaque handle:

#include "wickra.h"

struct Sma *sma = wickra_sma_new(14);     /* NULL on invalid params */
double v = wickra_sma_update(sma, 42.0);  /* NaN during warmup */
wickra_sma_reset(sma);                     /* back to fresh state */
wickra_sma_free(sma);                      /* exactly once per _new */

There is no RAII across the C boundary: every wickra_<ind>_new must be paired with exactly one wickra_<ind>_free. All functions are NULL-safe (a NULL handle yields NaN / a no-op, never a crash).