build packages in obj/ subdirectory that mimics $GOROOT/pkg.

for example, if building in src/lib/container,
objects go in obj/container/, so that 6g -Iobj
will find "container/vector".

install packages in hierarchy in $GOROOT.

this change only updates gobuild.
another change will have to update all
the sources to refer to "container/vector" etc
and regenerate all the Makefiles.

there are some pretty lame functions here
(e.g., Mkdir, Remove, the Getenv("PWD"))
but i will implement better ones in another CL.

R=r
DELTA=117  (99 added, 2 deleted, 16 changed)
OCL=27550
CL=27574

src/cmd/gobuild/Makefile

@@ -46,14 +46,29 @@ $(O1): newpkg
 $(O2): a1
 $(O3): a2
 
-gobuild: main.$O gobuild.a
+# zzgobuild is a fake target that will always run, even if
+# "gobuild" existed at the beginning of the make.
+# The problem is that if you "make install" and install
+# depends on gobuild and this rule says gobuild,
+# and gobuild.a depends on phases, "phases" gets
+# run, which cleans everything and then rebuilds
+# gobuild.a.  So now make thinks gobuild was up to date
+# to begin with (and it ran "phases" just for good measure)
+# but in fact gobuild is gone ("phases" removed it).
+#
+# Calling the target zzgobuild instead means that
+# make will always run this rule, rebuilding gobuild
+# before trying to install it.  Sigh.
+zzgobuild: main.$O gobuild.a
 	$(LD) -o gobuild main.$O
 
-main.$O: gobuild.a
+gobuild: zzgobuild
+
+main.$O: phases
 
 nuke: clean
 	rm -f $(HOME)/bin/gobuild
 
-install: gobuild
+install: zzgobuild
 	cp gobuild $(HOME)/bin/gobuild
 

src/cmd/gobuild/gobuild.go

@@ -45,6 +45,8 @@ type Phase struct {
 type Info struct {
 	Args []string;
 	Char string;
+	Dir string;
+	ObjDir string;
 	Pkgmap map[string] *Pkg;
 	Packages []*Pkg;
 	Files map[string] *File;
@@ -99,6 +101,30 @@ func (a FileArray) Swap(i, j int) {
 	a[i], a[j] = a[j], a[i]
 }
 
+// If current directory is under $GOROOT/src/lib, return the
+// path relative to there.  Otherwise return "".
+func PkgDir() string {
+	goroot, err := os.Getenv("GOROOT");
+	if err != nil || goroot == "" {
+		return ""
+	}
+	srcroot := path.Clean(goroot + "/src/lib/");
+	pwd, err1 := os.Getenv("PWD");	// TODO(rsc): real pwd
+	if err1 != nil || pwd == "" {
+		return ""
+	}
+	if pwd == srcroot {
+		return ""
+	}
+	n := len(srcroot);
+	if len(pwd) < n || pwd[n] != '/' || pwd[0:n] != srcroot {
+		return ""
+	}
+
+	dir := pwd[n+1:len(pwd)];
+	return dir;
+}
+
 func ScanFiles(filenames []string) *Info {
 	// Build list of imports, local packages, and files.
 	// Exclude *_test.go and anything in package main.
@@ -106,7 +132,9 @@ func ScanFiles(filenames []string) *Info {
 
 	z := new(Info);
 	z.Args = sys.Args;
-	z.Char = theChar;
+	z.Dir = PkgDir();
+	z.Char = theChar;	// for template
+	z.ObjDir = ObjDir;	// for template
 	z.Pkgmap = make(map[string] *Pkg);
 	z.Files = make(map[string] *File);
 	z.Imports = make(map[string] bool);
@@ -114,7 +142,7 @@ func ScanFiles(filenames []string) *Info {
 	// Read Go files to find out packages and imports.
 	var pkg *Pkg;
 	for _, filename := range filenames {
-		if strings.HasSuffix(filename, "_test.go") {
+		if strings.Index(filename, "_test.") >= 0 {
 			continue;
 		}
 		f := new(File);
@@ -168,6 +196,14 @@ func ScanFiles(filenames []string) *Info {
 		}
 	}
 
+	// Update destination directory.
+	// If destination directory has same
+	// name as package name, cut it off.
+	dir, name := path.Split(z.Dir);
+	if len(z.Packages) == 1 && z.Packages[0].Name == name {
+		z.Dir = dir;
+	}
+
 	return z;
 }
 
@@ -176,9 +212,14 @@ func PackageObj(pkg string) string {
 }
 
 func (z *Info) Build() {
+	// Create empty object directory tree.
+	RemoveAll(ObjDir);
+	obj := path.Join(ObjDir, z.Dir) + "/";
+	MkdirAll(obj);
+
 	// Create empty archives.
 	for pkgname := range z.Pkgmap {
-		ar := PackageObj(pkgname);
+		ar := obj + PackageObj(pkgname);
 		os.Remove(ar);
 		Archive(ar, nil);
 	}
@@ -239,7 +280,7 @@ func (z *Info) Build() {
 				f.Phase = phase;
 			}
 			if len(arfiles) > 0 {
-				Archive(pkg.Name + ".a", arfiles);
+				Archive(obj + pkg.Name + ".a", arfiles);
 
 				n := len(p.ArCmds);
 				p.ArCmds = p.ArCmds[0:n+1];
@@ -255,6 +296,7 @@ func (z *Info) Build() {
 }
 
 func (z *Info) Clean() {
+	RemoveAll(ObjDir);
 	for pkgname := range z.Pkgmap {
 		os.Remove(PackageObj(pkgname));
 	}

src/cmd/gobuild/makefile.go

@@ -16,13 +16,15 @@ var makefileTemplate =
 	"# DO NOT EDIT.  Automatically generated by gobuild.\n"
 	"{Args|args} >Makefile\n"
 	"\n"
+	"D={.section Dir}/{@}{.end}\n"
+	"\n"
 	"O_arm=5\n"	// TODO(rsc): include something here?
 	"O_amd64=6\n"
 	"O_386=8\n"
 	"OS=568vq\n"
 	"\n"
 	"O=$(O_$(GOARCH))\n"
-	"GC=$(O)g\n"
+	"GC=$(O)g -I{ObjDir}\n"
 	"CC=$(O)c -FVw\n"
 	"AS=$(O)a\n"
 	"AR=6ar\n"
@@ -30,7 +32,7 @@ var makefileTemplate =
 	"default: packages\n"
 	"\n"
 	"clean:\n"
-	"	rm -f *.[$(OS)] *.a [$(OS)].out\n"
+	"	rm -rf *.[$(OS)] *.a [$(OS)].out {ObjDir}\n"
 	"\n"
 	"test: packages\n"
 	"	gotest\n"
@@ -60,21 +62,22 @@ var makefileTemplate =
 	"\n"
 	"phases:{.repeated section Phases} a{Phase}{.end}\n"
 	"{.repeated section Packages}\n"
-	"{Name}.a: phases\n"
+	"{ObjDir}$D/{Name}.a: phases\n"
 	"{.end}\n"
 	"\n"
 	"{.repeated section Phases}\n"
 	"a{Phase}: $(O{Phase})\n"
 	"{.repeated section ArCmds}\n"
-	"	$(AR) grc {.section Pkg}{Name}.a{.end}{.repeated section Files} {Name|basename}.$O{.end}\n"
+	"	$(AR) grc {ObjDir}$D/{.section Pkg}{Name}.a{.end}{.repeated section Files} {Name|basename}.$O{.end}\n"
 	"{.end}\n"
 	"	rm -f $(O{Phase})\n"
 	"\n"
 	"{.end}\n"
 	"\n"
 	"newpkg: clean\n"
+	"	mkdir -p {ObjDir}$D\n"
 	"{.repeated section Packages}\n"
-	"	$(AR) grc {Name}.a\n"
+	"	$(AR) grc {ObjDir}$D/{Name}.a\n"
 	"{.end}\n"
 	"\n"
 	"$(O1): newpkg\n"
@@ -83,13 +86,14 @@ var makefileTemplate =
 	"{.end}\n"
 	"\n"
 	"nuke: clean\n"
-	"	rm -f{.repeated section Packages} $(GOROOT)/pkg/{Name}.a{.end}\n"
+	"	rm -f{.repeated section Packages} $(GOROOT)/pkg$D/{Name}.a{.end}\n"
 	"\n"
-	"packages:{.repeated section Packages} {Name}.a{.end}\n"
+	"packages:{.repeated section Packages} {ObjDir}$D/{Name}.a{.end}\n"
 	"\n"
 	"install: packages\n"
+	"	test -d $(GOROOT)/pkg && mkdir -p $(GOROOT)/pkg$D\n"
 	"{.repeated section Packages}\n"
-	"	cp {Name}.a $(GOROOT)/pkg/{Name}.a\n"
+	"	cp {ObjDir}$D/{Name}.a $(GOROOT)/pkg$D/{Name}.a\n"
 	"{.end}\n"
 
 func argsFmt(w io.Write, x interface{}, format string) {

src/cmd/gobuild/util.go

@@ -6,11 +6,11 @@
 package gobuild
 
 import (
-	"ast";
 	"exec";
 	"fmt";
+	"go/ast";
+	"go/parser";
 	"os";
-	"parser";
 	"path";
 	"sort";
 	"strconv";
@@ -30,6 +30,8 @@ var theChars = map[string] string {
 	"arm": "5"
 }
 
+const ObjDir = "_obj"
+
 func fatal(args ...) {
 	fmt.Fprintf(os.Stderr, "gobuild: %s\n", fmt.Sprint(args));
 	sys.Exit(1);
@@ -124,7 +126,7 @@ func Archive(pkg string, files []string) {
 func Compiler(file string) []string {
 	switch {
 	case strings.HasSuffix(file, ".go"):
-		return []string{ theChar + "g" };
+		return []string{ theChar + "g", "-I", ObjDir };
 	case strings.HasSuffix(file, ".c"):
 		return []string{ theChar + "c", "-FVw" };
 	case strings.HasSuffix(file, ".s"):
@@ -242,3 +244,37 @@ func SourceFiles(dir string) ([]string, *os.Error) {
 	sort.SortStrings(out);
 	return out, nil;
 }
+
+// TODO(rsc): Implement these for real as
+// os.MkdirAll and os.RemoveAll and then
+// make these wrappers that call fatal on error.
+
+func MkdirAll(name string) {
+	p, err := exec.Run("/bin/mkdir", []string{"mkdir", "-p", name}, os.Environ(), exec.DevNull, exec.PassThrough, exec.PassThrough);
+	if err != nil {
+		fatal("run /bin/mkdir: %v", err);
+	}
+	w, err1 := p.Wait(0);
+	if err1 != nil {
+		fatal("wait /bin/mkdir: %v", err);
+	}
+	if !w.Exited() || w.ExitStatus() != 0 {
+		fatal("/bin/mkdir: %v", w);
+	}
+}
+
+func RemoveAll(name string) {
+	p, err := exec.Run("/bin/rm", []string{"rm", "-rf", name}, os.Environ(), exec.DevNull, exec.PassThrough, exec.PassThrough);
+	if err != nil {
+		fatal("run /bin/rm: %v", err);
+	}
+	w, err1 := p.Wait(0);
+	if err1 != nil {
+		fatal("wait /bin/rm: %v", err);
+	}
+	if !w.Exited() || w.ExitStatus() != 0 {
+		fatal("/bin/rm: %v", w);
+	}
+
+}
+