all: split unix/windows support

Author: sbinet

README.md

@@ -55,9 +55,9 @@ ex:
  $ gopy gen github.com/go-python/gopy/_examples/hi
 
 Options:
-  -lang="py2": target language for bindings
+  -api="cpython": bindings API to use (cpython, cffi)
   -output="": output directory for bindings
-
+  -vm="python": path to python interpreter
 
 $ gopy help bind
 Usage: gopy bind <go-package-name>
@@ -69,8 +69,11 @@ ex:
  $ gopy bind github.com/go-python/gopy/_examples/hi
 
 Options:
-  -lang="py2": python version to use for bindings (python2|py2|python3|py3|cffi)
+  -api="cpython": bindings API to use (cpython, cffi)
   -output="": output directory for bindings
+  -symbols=true: include symbols in output
+  -vm="python": path to python interpreter
+  -work=false: print the name of temporary work directory and do not delete it when exiting
 ```
 
 

appveyor.yml

@@ -27,8 +27,7 @@ build_script:
   - "%CPYTHON3DIR%\\python -m pip install --upgrade pip"
   - "%CPYTHON2DIR%\\python -m pip install cffi"
   - "%CPYTHON3DIR%\\python -m pip install cffi"
-    #  - go get -v -t -tags purego ./... ## FIXME(sbinet)
+  - go get -v -t ./...
 
 test_script:
-  - go env
-    #  - go test -tags purego ./... ## FIXME(sbinet)
+  - go test ./...

bind/bind.go

@@ -27,12 +27,13 @@ func (list ErrorList) Error() string {
 }
 
 // GenCPython generates a (C)Python package from a Go package
-func GenCPython(w io.Writer, fset *token.FileSet, pkg *Package, lang int) error {
+func GenCPython(w io.Writer, fset *token.FileSet, pkg *Package, vm string, lang int) error {
 	gen := &cpyGen{
 		decl: &printer{buf: new(bytes.Buffer), indentEach: []byte("\t")},
 		impl: &printer{buf: new(bytes.Buffer), indentEach: []byte("\t")},
 		fset: fset,
 		pkg:  pkg,
+		vm:   vm,
 		lang: lang,
 	}
 	err := gen.gen()
@@ -60,11 +61,12 @@ func GenCPython(w io.Writer, fset *token.FileSet, pkg *Package, lang int) error
 // GenCFFI generates a wrapper python script by 2 steps.
 // First, GenCFFI analyzes which interfaces should be exposed from the Go package.
 // Then, GenCFFI writes a wrapper python script.
-func GenCFFI(w io.Writer, fset *token.FileSet, pkg *Package, lang int) error {
+func GenCFFI(w io.Writer, fset *token.FileSet, pkg *Package, vm string, lang int) error {
 	gen := &cffiGen{
 		wrapper: &printer{buf: new(bytes.Buffer), indentEach: []byte("    ")},
 		fset:    fset,
 		pkg:     pkg,
+		vm:      vm,
 		lang:    lang,
 	}
 
@@ -82,12 +84,13 @@ func GenCFFI(w io.Writer, fset *token.FileSet, pkg *Package, lang int) error {
 }
 
 // GenGo generates a cgo package from a Go package
-func GenGo(w io.Writer, fset *token.FileSet, pkg *Package, lang int, capi string) error {
+func GenGo(w io.Writer, fset *token.FileSet, pkg *Package, lang int, vm, capi string) error {
 	buf := new(bytes.Buffer)
 	gen := &goGen{
 		printer: &printer{buf: buf, indentEach: []byte("\t")},
 		fset:    fset,
 		pkg:     pkg,
+		vm:      vm,
 		lang:    lang,
 		capi:    capi,
 	}

bind/bind_unix.go

@@ -0,0 +1,11 @@
+// Copyright 2019 The go-python Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !windows
+
+package bind
+
+const (
+	shlibExt = ".so"
+)

bind/bind_windows.go

@@ -0,0 +1,11 @@
+// Copyright 2019 The go-python Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package bind
+
+const (
+	shlibExt = ".dll"
+)

bind/gencffi.go

@@ -66,7 +66,7 @@ extern void cgo_pkg_%[2]s_init();
 class _cffi_helper(object):
 
     here = os.path.dirname(os.path.abspath(__file__))
-    lib = ffi.dlopen(os.path.join(here, "_%[1]s.so"))
+    lib = ffi.dlopen(os.path.join(here, "_%[1]s%[2]s"))
 
     @staticmethod
     def cffi_cgopy_cnv_py2c_bool(o):
@@ -227,7 +227,8 @@ type cffiGen struct {
 	pkg  *Package
 	err  ErrorList
 
-	lang int // c-python api version (2,3)
+	vm   string // python interpreter
+	lang int    // c-python api version (2,3)
 }
 
 func (g *cffiGen) gen() error {
@@ -306,7 +307,7 @@ func (g *cffiGen) genCffiCdef() {
 
 func (g *cffiGen) genWrappedPy() {
 	n := g.pkg.pkg.Name()
-	g.wrapper.Printf(cffiHelperPreamble, n)
+	g.wrapper.Printf(cffiHelperPreamble, n, shlibExt)
 	g.wrapper.Indent()
 
 	// first, process slices, arrays

bind/gencpy.go

@@ -12,7 +12,7 @@ import (
 const (
 	cPreamble = `/*
   C stubs for package %[1]s.
-  gopy gen -lang=python %[1]s
+  gopy gen -api=cpython %[1]s
 
   File is generated by gopy gen. Do not edit.
 */
@@ -180,7 +180,8 @@ type cpyGen struct {
 	pkg  *Package
 	err  ErrorList
 
-	lang int // c-python api version (2,3)
+	vm   string // python interpreter
+	lang int    // c-python api version (2,3)
 }
 
 func (g *cpyGen) gen() error {

bind/gengo.go

@@ -43,7 +43,7 @@ func _cgopy_CheckGoVersion() {
 }
 `
 	goPreamble = `// Package main is an autogenerated binder stub for package %[1]s.
-// gopy gen -lang=go %[1]s
+// gopy gen %[1]s
 //
 // File is generated by gopy gen. Do not edit.
 package main
@@ -182,7 +182,8 @@ type goGen struct {
 
 	fset *token.FileSet
 	pkg  *Package
-	lang int // python's version API (2 or 3)
+	vm   string // python interpreter used to generate the bindings
+	lang int    // python's version API (2 or 3)
 	err  ErrorList
 	capi string
 }
@@ -1125,14 +1126,21 @@ func (g *goGen) genPreamble() {
 		pkgimport = fmt.Sprintf("_ %q", g.pkg.pkg.Path())
 	}
 
-	var pkgcfg string
-	var err error
+	var (
+		pkgcfg string
+		err    error
+	)
+
 	if g.capi == "cpython" {
-		pkgcfg, err = getPkgConfig(g.lang)
+		var pycfg pyconfig
+		pycfg, err = getPythonConfig(g.vm)
 		if err != nil {
 			panic(err)
 		}
-		pkgcfg = "//#cgo pkg-config: " + pkgcfg
+		pkgcfg = fmt.Sprintf(`//
+//#cgo CFLAGS: %s
+//#cgo LDFLAGS: %s
+//`, pycfg.cflags, pycfg.ldflags)
 	}
 
 	version := runtime.Version()

bind/utils.go

@@ -5,16 +5,17 @@
 package bind
 
 import (
-	"bufio"
 	"bytes"
+	"encoding/json"
 	"fmt"
 	"go/types"
-	"io"
+	"os"
 	"os/exec"
 	"regexp"
-	"sort"
 	"strconv"
 	"strings"
+
+	"github.com/pkg/errors"
 )
 
 func isErrorType(typ types.Type) bool {
@@ -83,68 +84,77 @@ func isConstructor(sig *types.Signature) bool {
 	return false
 }
 
-// getPkgConfig returns the name of the pkg-config python's pc file
-func getPkgConfig(vers int) (string, error) {
-	bin, err := exec.LookPath("pkg-config")
+type pyconfig struct {
+	version int
+	cflags  string
+	ldflags string
+}
+
+// getPythonConfig returns the needed python configuration for the given
+// python VM (python, python2, python3, pypy, etc...)
+func getPythonConfig(vm string) (pyconfig, error) {
+	code := `import sys
+import distutils.sysconfig as ds
+import json
+print(json.dumps({
+	"version": sys.version_info.major,
+	"incdir":  ds.get_python_inc(),
+	"libdir":  ds.get_config_var("LIBDIR"),
+	"libpy":   ds.get_config_var("LIBRARY"),
+	"shlibs":  ds.get_config_var("SHLIBS"),
+	"syslibs": ds.get_config_var("SYSLIBS"),
+	"shlinks": ds.get_config_var("LINKFORSHARED"),
+}))
+`
+
+	var cfg pyconfig
+	bin, err := exec.LookPath(vm)
 	if err != nil {
-		return "", fmt.Errorf(
-			"gopy: could not locate 'pkg-config' executable (err: %v)",
-			err,
-		)
+		return cfg, errors.Wrapf(err, "could not locate python vm %q", vm)
 	}
 
-	out, err := exec.Command(bin, "--list-all").Output()
+	buf := new(bytes.Buffer)
+	cmd := exec.Command(bin, "-c", code)
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = buf
+	cmd.Stderr = os.Stderr
+	err = cmd.Run()
 	if err != nil {
-		return "", fmt.Errorf(
-			"gopy: error retrieving the list of packages known to pkg-config (err: %v)",
-			err,
-		)
+		return cfg, errors.Wrap(err, "could not run python-config script")
 	}
 
-	pkgs := []string{}
-	re := regexp.MustCompile(fmt.Sprintf(`^python(\s|-|\.|)%d.*?`, vers))
-	s := bufio.NewScanner(bytes.NewReader(out))
-	for s.Scan() {
-		err = s.Err()
-		if err != nil {
-			if err == io.EOF {
-				err = nil
-			}
-			break
-		}
-
-		line := s.Bytes()
-		if !bytes.HasPrefix(line, []byte("python")) {
-			continue
-		}
-
-		if !re.Match(line) {
-			continue
-		}
-
-		pkg := bytes.Split(line, []byte(" "))
-		pkgs = append(pkgs, string(pkg[0]))
+	var raw struct {
+		Version int    `json:"version"`
+		IncDir  string `json:"incdir"`
+		LibDir  string `json:"libdir"`
+		LibPy   string `json:"libpy"`
+		ShLibs  string `json:"shlibs"`
+		SysLibs string `json:"syslibs"`
 	}
-
+	err = json.NewDecoder(buf).Decode(&raw)
 	if err != nil {
-		return "", fmt.Errorf(
-			"gopy: error scanning pkg-config output (err: %v)",
-			err,
-		)
+		return cfg, errors.Wrapf(err, "could not decode JSON script output")
 	}
 
-	if len(pkgs) <= 0 {
-		return "", fmt.Errorf(
-			"gopy: could not find pkg-config file (no python.pc installed?)",
-		)
+	if strings.HasSuffix(raw.LibPy, ".a") {
+		raw.LibPy = raw.LibPy[:len(raw.LibPy)-len(".a")]
+	}
+	if strings.HasPrefix(raw.LibPy, "lib") {
+		raw.LibPy = raw.LibPy[len("lib"):]
 	}
 
-	sort.Strings(pkgs)
-
-	// FIXME(sbinet): make sure we take the latest version?
-	pkgcfg := pkgs[0]
-
-	return pkgcfg, nil
+	cfg.version = raw.Version
+	cfg.cflags = strings.Join([]string{
+		"-I" + raw.IncDir,
+	}, " ")
+	cfg.ldflags = strings.Join([]string{
+		"-L" + raw.LibDir,
+		"-l" + raw.LibPy,
+		raw.ShLibs,
+		raw.SysLibs,
+	}, " ")
+
+	return cfg, nil
 }
 
 func getGoVersion(version string) (int64, int64, error) {

bind/utils_test.go

@@ -69,3 +69,29 @@ func TestExtractPythonName(t *testing.T) {
 		}
 	}
 }
+
+func TestPythonConfig(t *testing.T) {
+	t.Skip()
+
+	for _, tc := range []struct {
+		vm   string
+		want pyconfig
+	}{
+		{
+			vm: "python2",
+		},
+		{
+			vm: "python3",
+		},
+	} {
+		t.Run(tc.vm, func(t *testing.T) {
+			cfg, err := getPythonConfig(tc.vm)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if cfg != tc.want {
+				t.Fatalf("error:\ngot= %#v\nwant=%#v\n", cfg, tc.want)
+			}
+		})
+	}
+}