1 files changed, 444 insertions, 0 deletions
diff --git a/src/pkg/go/build/build.go b/src/pkg/go/build/build.go
new file mode 100644
index 000000000..97f92bfb6
--- /dev/null
+++ b/src/pkg/go/build/build.go
@@ -0,0 +1,444 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package build provides tools for building Go packages.
+package build
+
+import (
+	"bytes"
+	"exec"
+	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
+	"runtime"
+	"strings"
+)
+
+// Build produces a build Script for the given package.
+func Build(tree *Tree, pkg string, info *DirInfo) (*Script, os.Error) {
+	s := &Script{}
+	b := &build{
+		script: s,
+		path:   filepath.Join(tree.SrcDir(), pkg),
+	}
+	b.obj = b.abs("_obj") + string(filepath.Separator)
+
+	b.goarch = runtime.GOARCH
+	if g := os.Getenv("GOARCH"); g != "" {
+		b.goarch = g
+	}
+	var err os.Error
+	b.arch, err = ArchChar(b.goarch)
+	if err != nil {
+		return nil, err
+	}
+
+	// add import object files to list of Inputs
+	for _, pkg := range info.Imports {
+		t, p, err := FindTree(pkg)
+		if err != nil && err != ErrNotFound {
+			// FindTree should always be able to suggest an import
+			// path and tree. The path must be malformed
+			// (for example, an absolute or relative path).
+			return nil, os.NewError("build: invalid import: " + pkg)
+		}
+		s.addInput(filepath.Join(t.PkgDir(), p+".a"))
+	}
+
+	// .go files to be built with gc
+	gofiles := b.abss(info.GoFiles...)
+	s.addInput(gofiles...)
+
+	var ofiles []string // object files to be linked or packed
+
+	// make build directory
+	b.mkdir(b.obj)
+	s.addIntermediate(b.obj)
+
+	// cgo
+	if len(info.CgoFiles) > 0 {
+		cgoFiles := b.abss(info.CgoFiles...)
+		s.addInput(cgoFiles...)
+		cgoCFiles := b.abss(info.CFiles...)
+		s.addInput(cgoCFiles...)
+		outGo, outObj := b.cgo(cgoFiles, cgoCFiles)
+		gofiles = append(gofiles, outGo...)
+		ofiles = append(ofiles, outObj...)
+		s.addIntermediate(outGo...)
+		s.addIntermediate(outObj...)
+	}
+
+	// compile
+	if len(gofiles) > 0 {
+		ofile := b.obj + "_go_." + b.arch
+		b.gc(ofile, gofiles...)
+		ofiles = append(ofiles, ofile)
+		s.addIntermediate(ofile)
+	}
+
+	// assemble
+	for _, sfile := range info.SFiles {
+		ofile := b.obj + sfile[:len(sfile)-1] + b.arch
+		sfile = b.abs(sfile)
+		s.addInput(sfile)
+		b.asm(ofile, sfile)
+		ofiles = append(ofiles, ofile)
+		s.addIntermediate(ofile)
+	}
+
+	if len(ofiles) == 0 {
+		return nil, os.NewError("make: no object files to build")
+	}
+
+	// choose target file
+	var targ string
+	if info.IsCommand() {
+		// use the last part of the import path as binary name
+		_, bin := filepath.Split(pkg)
+		if runtime.GOOS == "windows" {
+			bin += ".exe"
+		}
+		targ = filepath.Join(tree.BinDir(), bin)
+	} else {
+		targ = filepath.Join(tree.PkgDir(), pkg+".a")
+	}
+
+	// make target directory
+	targDir, _ := filepath.Split(targ)
+	b.mkdir(targDir)
+
+	// link binary or pack object
+	if info.IsCommand() {
+		b.ld(targ, ofiles...)
+	} else {
+		b.gopack(targ, ofiles...)
+	}
+	s.Output = append(s.Output, targ)
+
+	return b.script, nil
+}
+
+// A Script describes the build process for a Go package.
+// The Input, Intermediate, and Output fields are lists of absolute paths.
+type Script struct {
+	Cmd          []*Cmd
+	Input        []string
+	Intermediate []string
+	Output       []string
+}
+
+func (s *Script) addInput(file ...string) {
+	s.Input = append(s.Input, file...)
+}
+
+func (s *Script) addIntermediate(file ...string) {
+	s.Intermediate = append(s.Intermediate, file...)
+}
+
+// Run runs the Script's Cmds in order.
+func (s *Script) Run() os.Error {
+	for _, c := range s.Cmd {
+		if err := c.Run(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Stale returns true if the build's inputs are newer than its outputs.
+func (s *Script) Stale() bool {
+	var latest int64
+	// get latest mtime of outputs
+	for _, file := range s.Output {
+		fi, err := os.Stat(file)
+		if err != nil {
+			// any error reading output files means stale
+			return true
+		}
+		if m := fi.Mtime_ns; m > latest {
+			latest = m
+		}
+	}
+	for _, file := range s.Input {
+		fi, err := os.Stat(file)
+		if err != nil || fi.Mtime_ns > latest {
+			// any error reading input files means stale
+			// (attempt to rebuild to figure out why)
+			return true
+		}
+	}
+	return false
+}
+
+// Clean removes the Script's Intermediate files.
+// It tries to remove every file and returns the first error it encounters.
+func (s *Script) Clean() (err os.Error) {
+	// Reverse order so that directories get removed after the files they contain.
+	for i := len(s.Intermediate) - 1; i >= 0; i-- {
+		if e := os.Remove(s.Intermediate[i]); err == nil {
+			err = e
+		}
+	}
+	return
+}
+
+// Nuke removes the Script's Intermediate and Output files.
+// It tries to remove every file and returns the first error it encounters.
+func (s *Script) Nuke() (err os.Error) {
+	// Reverse order so that directories get removed after the files they contain.
+	for i := len(s.Output) - 1; i >= 0; i-- {
+		if e := os.Remove(s.Output[i]); err == nil {
+			err = e
+		}
+	}
+	if e := s.Clean(); err == nil {
+		err = e
+	}
+	return
+}
+
+// A Cmd describes an individual build command.
+type Cmd struct {
+	Args   []string // command-line
+	Stdout string   // write standard output to this file, "" is passthrough
+	Dir    string   // working directory
+	Env    []string // environment
+	Input  []string // file paths (dependencies)
+	Output []string // file paths
+}
+
+func (c *Cmd) String() string {
+	return strings.Join(c.Args, " ")
+}
+
+// Run executes the Cmd.
+func (c *Cmd) Run() os.Error {
+	if c.Args[0] == "mkdir" {
+		for _, p := range c.Output {
+			if err := os.MkdirAll(p, 0777); err != nil {
+				return fmt.Errorf("command %q: %v", c, err)
+			}
+		}
+		return nil
+	}
+	out := new(bytes.Buffer)
+	cmd := exec.Command(c.Args[0], c.Args[1:]...)
+	cmd.Dir = c.Dir
+	cmd.Env = c.Env
+	cmd.Stdout = out
+	cmd.Stderr = out
+	if c.Stdout != "" {
+		f, err := os.Create(c.Stdout)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+		cmd.Stdout = f
+	}
+	if err := cmd.Run(); err != nil {
+		return fmt.Errorf("command %q: %v\n%v", c, err, out)
+	}
+	return nil
+}
+
+// ArchChar returns the architecture character for the given goarch.
+// For example, ArchChar("amd64") returns "6".
+func ArchChar(goarch string) (string, os.Error) {
+	switch goarch {
+	case "386":
+		return "8", nil
+	case "amd64":
+		return "6", nil
+	case "arm":
+		return "5", nil
+	}
+	return "", os.NewError("unsupported GOARCH " + goarch)
+}
+
+type build struct {
+	script *Script
+	path   string
+	obj    string
+	goarch string
+	arch   string
+}
+
+func (b *build) abs(file string) string {
+	if filepath.IsAbs(file) {
+		return file
+	}
+	return filepath.Join(b.path, file)
+}
+
+func (b *build) abss(file ...string) []string {
+	s := make([]string, len(file))
+	for i, f := range file {
+		s[i] = b.abs(f)
+	}
+	return s
+}
+
+func (b *build) add(c Cmd) {
+	b.script.Cmd = append(b.script.Cmd, &c)
+}
+
+func (b *build) mkdir(name string) {
+	b.add(Cmd{
+		Args:   []string{"mkdir", "-p", name},
+		Output: []string{name},
+	})
+}
+
+func (b *build) gc(ofile string, gofiles ...string) {
+	gc := b.arch + "g"
+	args := append([]string{gc, "-o", ofile}, gcImportArgs...)
+	args = append(args, gofiles...)
+	b.add(Cmd{
+		Args:   args,
+		Input:  gofiles,
+		Output: []string{ofile},
+	})
+}
+
+func (b *build) asm(ofile string, sfile string) {
+	asm := b.arch + "a"
+	b.add(Cmd{
+		Args:   []string{asm, "-o", ofile, sfile},
+		Input:  []string{sfile},
+		Output: []string{ofile},
+	})
+}
+
+func (b *build) ld(targ string, ofiles ...string) {
+	ld := b.arch + "l"
+	args := append([]string{ld, "-o", targ}, ldImportArgs...)
+	args = append(args, ofiles...)
+	b.add(Cmd{
+		Args:   args,
+		Input:  ofiles,
+		Output: []string{targ},
+	})
+}
+
+func (b *build) gopack(targ string, ofiles ...string) {
+	b.add(Cmd{
+		Args:   append([]string{"gopack", "grc", targ}, ofiles...),
+		Input:  ofiles,
+		Output: []string{targ},
+	})
+}
+
+func (b *build) cc(ofile string, cfiles ...string) {
+	cc := b.arch + "c"
+	dir := fmt.Sprintf("%s_%s", runtime.GOOS, runtime.GOARCH)
+	inc := filepath.Join(runtime.GOROOT(), "pkg", dir)
+	args := []string{cc, "-FVw", "-I", inc, "-o", ofile}
+	b.add(Cmd{
+		Args:   append(args, cfiles...),
+		Input:  cfiles,
+		Output: []string{ofile},
+	})
+}
+
+func (b *build) gccCompile(ofile, cfile string) {
+	b.add(Cmd{
+		Args:   b.gccArgs("-o", ofile, "-c", cfile),
+		Input:  []string{cfile},
+		Output: []string{ofile},
+	})
+}
+
+func (b *build) gccLink(ofile string, ofiles ...string) {
+	b.add(Cmd{
+		Args:   append(b.gccArgs("-o", ofile), ofiles...),
+		Input:  ofiles,
+		Output: []string{ofile},
+	})
+}
+
+func (b *build) gccArgs(args ...string) []string {
+	// TODO(adg): HOST_CC
+	a := []string{"gcc", "-I", b.path, "-g", "-fPIC", "-O2"}
+	switch b.arch {
+	case "8":
+		a = append(a, "-m32")
+	case "6":
+		a = append(a, "-m64")
+	}
+	return append(a, args...)
+}
+
+var cgoRe = regexp.MustCompile(`[/\\:]`)
+
+func (b *build) cgo(cgofiles, cgocfiles []string) (outGo, outObj []string) {
+	// cgo
+	// TODO(adg): CGOPKGPATH
+	// TODO(adg): CGO_FLAGS
+	gofiles := []string{b.obj + "_cgo_gotypes.go"}
+	cfiles := []string{b.obj + "_cgo_main.c", b.obj + "_cgo_export.c"}
+	for _, fn := range cgofiles {
+		f := b.obj + cgoRe.ReplaceAllString(fn[:len(fn)-2], "_")
+		gofiles = append(gofiles, f+"cgo1.go")
+		cfiles = append(cfiles, f+"cgo2.c")
+	}
+	defunC := b.obj + "_cgo_defun.c"
+	output := append([]string{defunC}, cfiles...)
+	output = append(output, gofiles...)
+	b.add(Cmd{
+		Args:   append([]string{"cgo", "--"}, cgofiles...),
+		Dir:    b.path,
+		Env:    append(os.Environ(), "GOARCH="+b.goarch),
+		Input:  cgofiles,
+		Output: output,
+	})
+	outGo = append(outGo, gofiles...)
+	exportH := filepath.Join(b.path, "_cgo_export.h")
+	b.script.addIntermediate(defunC, exportH, b.obj+"_cgo_flags")
+	b.script.addIntermediate(cfiles...)
+
+	// cc _cgo_defun.c
+	defunObj := b.obj + "_cgo_defun." + b.arch
+	b.cc(defunObj, defunC)
+	outObj = append(outObj, defunObj)
+
+	// gcc
+	linkobj := make([]string, 0, len(cfiles))
+	for _, cfile := range cfiles {
+		ofile := cfile[:len(cfile)-1] + "o"
+		b.gccCompile(ofile, cfile)
+		linkobj = append(linkobj, ofile)
+		if !strings.HasSuffix(ofile, "_cgo_main.o") {
+			outObj = append(outObj, ofile)
+		} else {
+			b.script.addIntermediate(ofile)
+		}
+	}
+	for _, cfile := range cgocfiles {
+		ofile := b.obj + cgoRe.ReplaceAllString(cfile[:len(cfile)-1], "_") + "o"
+		b.gccCompile(ofile, cfile)
+		linkobj = append(linkobj, ofile)
+		outObj = append(outObj, ofile)
+	}
+	dynObj := b.obj + "_cgo_.o"
+	b.gccLink(dynObj, linkobj...)
+	b.script.addIntermediate(dynObj)
+
+	// cgo -dynimport
+	importC := b.obj + "_cgo_import.c"
+	b.add(Cmd{
+		Args:   []string{"cgo", "-dynimport", dynObj},
+		Stdout: importC,
+		Input:  []string{dynObj},
+		Output: []string{importC},
+	})
+	b.script.addIntermediate(importC)
+
+	// cc _cgo_import.ARCH
+	importObj := b.obj + "_cgo_import." + b.arch
+	b.cc(importObj, importC)
+	outObj = append(outObj, importObj)
+
+	return
+}