initial commit

loader.go

@@ -0,0 +1,85 @@
+package talib
+
+import (
+	"fmt"
+	"log/slog"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"github.com/ebitengine/purego"
+)
+
+func Load() (uintptr, error) {
+	var (
+		path string
+		ptr  uintptr
+		err  error
+	)
+
+	if path, err = getExpectedLibraryPath(); err != nil {
+		return 0, err
+	}
+
+	slog.Debug("Loading TA-Lib library", "path", path)
+	if ptr, err = purego.Dlopen(path, purego.RTLD_NOW|purego.RTLD_GLOBAL); err != nil {
+		return 0, err
+	}
+
+	// Register the functions we need from the TA-Lib library
+	purego.RegisterLibFunc(&ht_dcperiod, ptr, "TA_HT_DCPERIOD")
+	purego.RegisterLibFunc(&ht_dcphase, ptr, "TA_HT_DCPHASE")
+	purego.RegisterLibFunc(&ht_phasor, ptr, "TA_HT_PHASOR")
+	purego.RegisterLibFunc(&ht_sine, ptr, "TA_HT_SINE")
+	purego.RegisterLibFunc(&ht_trendmode, ptr, "TA_HT_TRENDMODE")
+	purego.RegisterLibFunc(&add, ptr, "TA_ADD")
+
+	return ptr, nil
+}
+
+func getExpectedLibraryName() (string, error) {
+	switch runtime.GOOS {
+	case "windows":
+		return "libta-lib.dll", nil
+	case "darwin":
+		return "libta-lib.dylib", nil
+	case "linux":
+		return "libta-lib.so", nil
+	default:
+		return "", fmt.Errorf("unsupported platform: %s", runtime.GOOS)
+	}
+}
+
+func getExpectedLibraryPath() (string, error) {
+	libName, err := getExpectedLibraryName()
+	if err != nil {
+		return "", err
+	}
+
+	isExist := func(path string) bool {
+		_, err := os.Stat(path)
+		return err == nil
+	}
+
+	if envpath, ok := os.LookupEnv("TA_LIB_PATH"); ok {
+		p := filepath.Join(envpath, libName)
+		if isExist(p) {
+			return p, nil
+		}
+
+		slog.Debug("TA_LIB_PATH environment variable is set but library not found", "path", p)
+	}
+
+	for _, dir := range []string{
+		".",
+		"/usr/local/lib",
+		"/usr/lib",
+	} {
+		p := filepath.Join(dir, libName)
+		if isExist(p) {
+			return p, nil
+		}
+	}
+
+	return "", fmt.Errorf("library not found: %s", libName)
+}