Interpreter lifecycle

.gitignore

@@ -10,3 +10,4 @@
 
 # Output of the go coverage tool, specifically when used with LiteIDE
 *.out
+vendor

lifecycle.go

@@ -0,0 +1,280 @@
+package python3
+
+/*
+#include "Python.h"
+*/
+import "C"
+import (
+	"fmt"
+	"unsafe"
+)
+
+// The argument for Py_SetProgramName, Py_SetPath and Py_SetPythonHome should point to a zero-terminated wide character string in static storage
+// whose contents will not change for the duration of the program’s execution
+var (
+	programName *C.wchar_t
+	pythonPath  *C.wchar_t
+	pythonHome  *C.wchar_t
+)
+
+//Py_Initialize : https://docs.python.org/3/c-api/init.html#c.Py_Initialize
+func Py_Initialize() {
+	C.Py_Initialize()
+}
+
+//Py_InitializeEx : https://docs.python.org/3/c-api/init.html#c.Py_InitializeEx
+func Py_InitializeEx(initsigs bool) {
+	if initsigs {
+		C.Py_InitializeEx(1)
+	} else {
+		C.Py_InitializeEx(0)
+	}
+}
+
+//Py_IsInitialized : https://docs.python.org/3/c-api/init.html#c.Py_IsInitialized
+func Py_IsInitialized() bool {
+	return C.Py_IsInitialized() != 0
+}
+
+//Py_FinalizeEx : https://docs.python.org/3/c-api/init.html#c.Py_FinalizeEx
+func Py_FinalizeEx() int {
+	return int(C.Py_FinalizeEx())
+}
+
+//Py_Finalize : https://docs.python.org/3/c-api/init.html#c.Py_Finalize
+func Py_Finalize() {
+	C.Py_Finalize()
+}
+
+//Py_SetStandardStreamEncoding : https://docs.python.org/3/c-api/init.html#c.Py_SetStandardStreamEncoding
+func Py_SetStandardStreamEncoding(encoding, errors string) int {
+	cencoding := C.CString(encoding)
+	defer C.free(unsafe.Pointer(cencoding))
+
+	cerrors := C.CString(errors)
+	defer C.free(unsafe.Pointer(cerrors))
+
+	return int(C.Py_SetStandardStreamEncoding(cencoding, cerrors))
+
+}
+
+//Py_SetProgramName : https://docs.python.org/3/c-api/init.html#c.Py_SetProgramName
+func Py_SetProgramName(name string) error {
+	cname := C.CString(name)
+	defer C.free(unsafe.Pointer(cname))
+
+	newProgramName := C.Py_DecodeLocale(cname, nil)
+	if newProgramName == nil {
+		return fmt.Errorf("fail to call Py_DecodeLocale on '%s'", name)
+	}
+	C.Py_SetProgramName(newProgramName)
+
+	//no operation is performed if nil
+	C.PyMem_RawFree(unsafe.Pointer(programName))
+	programName = newProgramName
+
+	return nil
+}
+
+//Py_GetProgramName : https://docs.python.org/3/c-api/init.html#c.Py_GetProgramName
+func Py_GetProgramName() (string, error) {
+	wcname := C.Py_GetProgramName()
+	if wcname == nil {
+		return "", nil
+	}
+	cname := C.Py_EncodeLocale(wcname, nil)
+	if cname == nil {
+		return "", fmt.Errorf("fail to call Py_EncodeLocale")
+	}
+	defer C.PyMem_Free(unsafe.Pointer(cname))
+
+	return C.GoString(cname), nil
+}
+
+//Py_GetPrefix : https://docs.python.org/3/c-api/init.html#c.Py_GetPrefix
+func Py_GetPrefix() (string, error) {
+	wcname := C.Py_GetPrefix()
+	if wcname == nil {
+		return "", nil
+	}
+	cname := C.Py_EncodeLocale(wcname, nil)
+	if cname == nil {
+		return "", fmt.Errorf("fail to call Py_EncodeLocale")
+	}
+	defer C.PyMem_Free(unsafe.Pointer(cname))
+
+	return C.GoString(cname), nil
+}
+
+//Py_GetExecPrefix : https://docs.python.org/3/c-api/init.html#c.Py_GetExecPrefix
+func Py_GetExecPrefix() (string, error) {
+	wcname := C.Py_GetExecPrefix()
+	if wcname == nil {
+		return "", nil
+	}
+	cname := C.Py_EncodeLocale(wcname, nil)
+	if cname == nil {
+		return "", fmt.Errorf("fail to call Py_EncodeLocale")
+	}
+	defer C.PyMem_Free(unsafe.Pointer(cname))
+
+	return C.GoString(cname), nil
+}
+
+//Py_GetProgramFullPath : https://docs.python.org/3/c-api/init.html#c.Py_GetProgramFullPath
+func Py_GetProgramFullPath() (string, error) {
+	wcname := C.Py_GetProgramFullPath()
+	if wcname == nil {
+		return "", nil
+	}
+	cname := C.Py_EncodeLocale(wcname, nil)
+	if cname == nil {
+		return "", fmt.Errorf("fail to call Py_EncodeLocale")
+	}
+	defer C.PyMem_Free(unsafe.Pointer(cname))
+
+	return C.GoString(cname), nil
+}
+
+//Py_GetPath : https://docs.python.org/3/c-api/init.html#c.Py_GetPath
+func Py_GetPath() (string, error) {
+	wcname := C.Py_GetPath()
+	if wcname == nil {
+		return "", nil
+	}
+	cname := C.Py_EncodeLocale(wcname, nil)
+	if cname == nil {
+		return "", fmt.Errorf("fail to call Py_EncodeLocale")
+	}
+	defer C.PyMem_Free(unsafe.Pointer(cname))
+
+	return C.GoString(cname), nil
+}
+
+//Py_SetPath : https://docs.python.org/3/c-api/init.html#c.Py_SetPath
+func Py_SetPath(path string) error {
+	cpath := C.CString(path)
+	defer C.free(unsafe.Pointer(cpath))
+
+	newPath := C.Py_DecodeLocale(cpath, nil)
+	if newPath == nil {
+		return fmt.Errorf("fail to call Py_DecodeLocale on '%s'", path)
+	}
+	C.Py_SetPath(newPath)
+
+	C.PyMem_RawFree(unsafe.Pointer(pythonPath))
+	pythonHome = newPath
+
+	return nil
+}
+
+//Py_GetVersion : https://docs.python.org/3/c-api/init.html#c.Py_GetVersion
+func Py_GetVersion() string {
+	cversion := C.Py_GetVersion()
+	return C.GoString(cversion)
+}
+
+//Py_GetPlatform : https://docs.python.org/3/c-api/init.html#c.Py_GetPlatform
+func Py_GetPlatform() string {
+	cplatform := C.Py_GetPlatform()
+	return C.GoString(cplatform)
+}
+
+//Py_GetCopyright : https://docs.python.org/3/c-api/init.html#c.Py_GetCopyright
+func Py_GetCopyright() string {
+	ccopyright := C.Py_GetCopyright()
+	return C.GoString(ccopyright)
+}
+
+//Py_GetCompiler : https://docs.python.org/3/c-api/init.html#c.Py_GetCompiler
+func Py_GetCompiler() string {
+	ccompiler := C.Py_GetCompiler()
+	return C.GoString(ccompiler)
+}
+
+//Py_GetBuildInfo : https://docs.python.org/3/c-api/init.html#c.Py_GetBuildInfo
+func Py_GetBuildInfo() string {
+	cbuildInfo := C.Py_GetBuildInfo()
+	return C.GoString(cbuildInfo)
+}
+
+//PySys_SetArgvEx : https://docs.python.org/3/c-api/init.html#c.PySys_SetArgvEx
+func PySys_SetArgvEx(args []string, updatepath bool) error {
+	argc := C.int(len(args))
+	argv := make([]*C.wchar_t, argc, argc)
+	for i, arg := range args {
+		carg := C.CString(arg)
+		defer C.free(unsafe.Pointer(carg))
+
+		warg := C.Py_DecodeLocale(carg, nil)
+		if warg == nil {
+			return fmt.Errorf("fail to call Py_DecodeLocale on '%s'", arg)
+		}
+		// Py_DecodeLocale requires a call to PyMem_RawFree to free the memory
+		defer C.PyMem_RawFree(unsafe.Pointer(warg))
+
+		argv[i] = warg
+	}
+
+	if updatepath {
+		C.PySys_SetArgvEx(argc, (**C.wchar_t)(unsafe.Pointer(&argv[0])), 1)
+	} else {
+		C.PySys_SetArgvEx(argc, (**C.wchar_t)(unsafe.Pointer(&argv[0])), 0)
+	}
+
+	return nil
+}
+
+//PySys_SetArgv : https://docs.python.org/3/c-api/init.html#c.PySys_SetArgv
+func PySys_SetArgv(args []string) error {
+	argc := C.int(len(args))
+	argv := make([]*C.wchar_t, argc, argc)
+	for i, arg := range args {
+		carg := C.CString(arg)
+		defer C.free(unsafe.Pointer(carg))
+
+		warg := C.Py_DecodeLocale(carg, nil)
+		if warg == nil {
+			return fmt.Errorf("fail to call Py_DecodeLocale on '%s'", arg)
+		}
+		// Py_DecodeLocale requires a call to PyMem_RawFree to free the memory
+		defer C.PyMem_RawFree(unsafe.Pointer(warg))
+
+		argv[i] = warg
+	}
+	C.PySys_SetArgv(argc, (**C.wchar_t)(unsafe.Pointer(&argv[0])))
+
+	return nil
+}
+
+//Py_SetPythonHome : https://docs.python.org/3/c-api/init.html#c.Py_SetPythonHome
+func Py_SetPythonHome(home string) error {
+	chome := C.CString(home)
+	defer C.free(unsafe.Pointer(chome))
+
+	newHome := C.Py_DecodeLocale(chome, nil)
+	if newHome == nil {
+		return fmt.Errorf("fail to call Py_DecodeLocale on '%s'", home)
+	}
+	C.Py_SetPythonHome(newHome)
+
+	C.PyMem_RawFree(unsafe.Pointer(pythonHome))
+	pythonHome = newHome
+
+	return nil
+}
+
+//Py_GetPythonHome : https://docs.python.org/3/c-api/init.html#c.Py_GetPythonHome
+func Py_GetPythonHome() (string, error) {
+	wchome := C.Py_GetPythonHome()
+	if wchome == nil {
+		return "", nil
+	}
+	chome := C.Py_EncodeLocale(wchome, nil)
+	if chome == nil {
+		return "", fmt.Errorf("fail to call Py_EncodeLocale")
+	}
+	defer C.PyMem_Free(unsafe.Pointer(chome))
+
+	return C.GoString(chome), nil
+}

lifecycle_test.go

@@ -0,0 +1,114 @@
+package python3
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestInitialization(t *testing.T) {
+
+	Py_Initialize()
+	assert.True(t, Py_IsInitialized())
+	Py_Finalize()
+	assert.False(t, Py_IsInitialized())
+
+}
+
+func TestInitializationEx(t *testing.T) {
+
+	Py_Initialize()
+	assert.True(t, Py_IsInitialized())
+	assert.Zero(t, Py_FinalizeEx())
+	assert.False(t, Py_IsInitialized())
+
+}
+
+func TestProgramName(t *testing.T) {
+	Py_Finalize()
+
+	defaultName, err := Py_GetProgramName()
+	defer Py_SetProgramName(defaultName)
+
+	assert.Nil(t, err)
+	name := "py3é"
+	Py_SetProgramName(name)
+	newName, err := Py_GetProgramName()
+	assert.Nil(t, err)
+	assert.Equal(t, name, newName)
+
+}
+
+func TestPrefix(t *testing.T) {
+	prefix, err := Py_GetPrefix()
+	assert.Nil(t, err)
+	assert.IsType(t, "", prefix)
+
+}
+
+func TestExecPrefix(t *testing.T) {
+	execPrefix, err := Py_GetExecPrefix()
+	assert.Nil(t, err)
+	assert.IsType(t, "", execPrefix)
+
+}
+
+func TestProgramFullPath(t *testing.T) {
+	programFullPath, err := Py_GetProgramFullPath()
+	assert.Nil(t, err)
+	assert.IsType(t, "", programFullPath)
+
+}
+
+func TestPath(t *testing.T) {
+	Py_Finalize()
+
+	defaultPath, err := Py_GetPath()
+	defer Py_SetPath(defaultPath)
+
+	assert.Nil(t, err)
+	name := "påth"
+	Py_SetPath(name)
+	newName, err := Py_GetPath()
+	assert.Nil(t, err)
+	assert.Equal(t, name, newName)
+
+}
+
+func TestVersion(t *testing.T) {
+	version := Py_GetVersion()
+	assert.IsType(t, "", version)
+}
+
+func TestPlatform(t *testing.T) {
+	platform := Py_GetPlatform()
+	assert.IsType(t, "", platform)
+}
+
+func TestCopyright(t *testing.T) {
+	copyright := Py_GetCopyright()
+	assert.IsType(t, "", copyright)
+}
+
+func TestCompiler(t *testing.T) {
+	compiler := Py_GetCompiler()
+	assert.IsType(t, "", compiler)
+}
+
+func TestBuildInfo(t *testing.T) {
+	buildInfo := Py_GetBuildInfo()
+	assert.IsType(t, "", buildInfo)
+}
+
+func TestPythonHome(t *testing.T) {
+	name := "høme"
+
+	defaultHome, err := Py_GetPythonHome()
+	defer Py_SetPythonHome(defaultHome)
+
+	assert.Nil(t, err)
+	Py_SetPythonHome(name)
+	newName, err := Py_GetPythonHome()
+	assert.Nil(t, err)
+	assert.Equal(t, name, newName)
+}