devtools/src/jehanne/cmd/build/build.go

670 lines
16 KiB
Go

// Build builds code as directed by json files.
// We slurp in the JSON, and recursively process includes.
// At the end, we issue a single cc command for all the files.
// Compilers are fast.
//
// ENVIRONMENT
//
// Needed: JEHANNE, ARCH
//
// JEHANNE should point to a Jehanne root.
// Currently only "amd64" is a valid ARCH.
// A best-effort to autodetect the Jehanne root is made if not explicitly set.
//
// Optional: CC, AR, LD, RANLIB, STRIP, SH, TOOLPREFIX
//
// These all control how the needed tools are found.
//
package main
import (
"encoding/json"
"flag"
"fmt"
"io"
"io/ioutil"
"log"
"os"
"os/exec"
"path"
"path/filepath"
"regexp"
"sort"
"strings"
)
type kernconfig struct {
Code []string
Dev []string
Ip []string
Link []string
Sd []string
Uart []string
VGA []string
}
type kernel struct {
CodeFile string
Systab string
Config kernconfig
Ramfiles map[string]string
}
type build struct {
// jsons is unexported so can not be set in a .json file
jsons map[string]bool
path string
name string
// Projects name a whole subproject which is built independently of
// this one. We'll need to be able to use environment variables at some point.
Projects []string
Pre []string
Post []string
Cflags []string
Oflags []string
Include []string
SourceFiles []string
ObjectFiles []string
Libs []string
Env []string
// cmd's
SourceFilesCmd []string
// Targets.
Program string
Library string
Install string // where to place the resulting binary/lib
Kernel *kernel
}
type buildfile map[string]build
// UnmarshalJSON works like the stdlib unmarshal would, except it adjusts all
// paths.
func (bf *buildfile) UnmarshalJSON(s []byte) error {
r := make(map[string]build)
if err := json.Unmarshal(s, &r); err != nil {
return err
}
for k, b := range r {
// we're getting a copy of the struct, remember.
b.jsons = make(map[string]bool)
b.Projects = adjust(b.Projects)
b.Libs = adjust(b.Libs)
b.Cflags = adjust(b.Cflags)
b.SourceFiles = b.SourceFiles
b.SourceFilesCmd = b.SourceFilesCmd
b.ObjectFiles = b.ObjectFiles
b.Include = adjust(b.Include)
b.Install = fromRoot(b.Install)
for i, e := range b.Env {
b.Env[i] = os.ExpandEnv(e)
}
r[k] = b
}
*bf = r
return nil
}
var (
cwd string
jehanne string
regexpAll = []*regexp.Regexp{regexp.MustCompile(".")}
// findTools looks at all env vars and absolutizes these paths
// also respects TOOLPREFIX
tools = map[string]string{
"cc": "gcc",
"ar": "ar",
"ld": "ld",
"ranlib": "ranlib",
"strip": "strip",
"sh": "sh",
}
arch = map[string]bool{
"amd64": true,
}
debugPrint = flag.Bool("debug", false, "enable debug prints")
shellhack = flag.Bool("shellhack", false, "spawn every command in a shell (forced on if LD_PRELOAD is set)")
)
func debug(fmt string, s ...interface{}) {
if *debugPrint {
log.Printf(fmt, s...)
}
}
// fail with message, if err is not nil
func failOn(err error) {
if err != nil {
log.Fatalf("%v\n", err)
}
}
func isValueInList(value string, list []string) bool {
for _, v := range list {
if v == value {
return true
}
}
return false
}
func adjust(s []string) []string {
for i, v := range s {
s[i] = fromRoot(v)
}
return s
}
func buildEnv(b *build) func(string) string{
return func(v string) string {
search := v + "="
for _, s := range b.Env {
if strings.Index(s, search) == 0 {
return strings.Replace(s, search, "", 1)
}
}
return os.Getenv(v)
}
}
// return the given absolute path as an absolute path rooted at the jehanne tree.
func fromRoot(p string) string {
p = os.ExpandEnv(p)
if path.IsAbs(p) {
return path.Join(jehanne, p)
}
return p
}
// Sh sends cmd to a shell. It's needed to enable $LD_PRELOAD tricks,
// see https://github.com/Harvey-OS/jehanne/issues/8#issuecomment-131235178
func sh(cmd *exec.Cmd) {
shell := exec.Command(tools["sh"])
shell.Env = cmd.Env
if cmd.Args[0] == tools["sh"] && cmd.Args[1] == "-c" {
cmd.Args = cmd.Args[2:]
}
commandString := strings.Join(cmd.Args, " ")
if shStdin, e := shell.StdinPipe(); e == nil {
go func() {
defer shStdin.Close()
io.WriteString(shStdin, commandString)
}()
} else {
log.Fatalf("cannot pipe [%v] to %s: %v", commandString, tools["sh"], e)
}
shell.Stderr = os.Stderr
shell.Stdout = os.Stdout
debug("%q | sh\n", commandString)
failOn(shell.Run())
}
func mergeKernel(k *kernel, defaults *kernel) *kernel {
if k == nil {
return defaults
}
if defaults == nil {
return k
}
// The custom kernel Code will be added after the default from includes
// so that it has a chance to change de default behaviour.
k.Config.Code = append(defaults.Config.Code, k.Config.Code...)
k.Config.Dev = append(k.Config.Dev, defaults.Config.Dev...)
k.Config.Ip = append(k.Config.Ip, defaults.Config.Ip...)
k.Config.Link = append(k.Config.Link, defaults.Config.Link...)
k.Config.Sd = append(k.Config.Sd, defaults.Config.Sd...)
k.Config.Uart = append(k.Config.Uart, defaults.Config.Uart...)
k.Config.VGA = append(k.Config.VGA, defaults.Config.VGA...)
if k.CodeFile == "" {
k.CodeFile = defaults.CodeFile
}
if k.Systab == "" {
k.Systab = defaults.Systab
}
for name, path := range defaults.Ramfiles {
if _, ok := k.Ramfiles[name]; ok == false {
k.Ramfiles[name] = path
}
}
return k
}
func include(f string, b *build) {
if b.jsons[f] {
return
}
b.jsons[f] = true
log.Printf("Including %v", f)
d, err := ioutil.ReadFile(f)
failOn(err)
var builds buildfile
failOn(json.Unmarshal(d, &builds))
for n, build := range builds {
log.Printf("Merging %v", n)
b.SourceFiles = append(b.SourceFiles, build.SourceFiles...)
b.Cflags = append(b.Cflags, build.Cflags...)
b.Oflags = append(b.Oflags, build.Oflags...)
b.Pre = append(b.Pre, build.Pre...)
b.Post = append(b.Post, build.Post...)
b.Libs = append(b.Libs, build.Libs...)
b.Projects = append(b.Projects, build.Projects...)
b.Env = append(b.Env, build.Env...)
b.SourceFilesCmd = append(b.SourceFilesCmd, build.SourceFilesCmd...)
b.Program += build.Program
b.Library += build.Library
b.Kernel = mergeKernel(b.Kernel, build.Kernel)
if build.Install != "" {
if b.Install != "" {
log.Fatalf("In file %s (target %s) included by %s (target %s): redefined Install.", f, n, build.path, build.name)
}
b.Install = build.Install
}
b.ObjectFiles = append(b.ObjectFiles, build.ObjectFiles...)
// For each source file, assume we create an object file with the last char replaced
// with 'o'. We can get smarter later.
for _, v := range build.SourceFiles {
f := path.Base(v)
o := f[:len(f)-1] + "o"
b.ObjectFiles = append(b.ObjectFiles, o)
}
for _, v := range build.Include {
if !path.IsAbs(v) {
wd := path.Dir(f)
v = path.Join(wd, v)
}
include(v, b)
}
}
}
func appendIfMissing(s []string, v string) []string {
for _, a := range s {
if a == v {
return s
}
}
return append(s, v)
}
func process(f string, r []*regexp.Regexp) []build {
log.Printf("Processing %v", f)
var builds buildfile
var results []build
d, err := ioutil.ReadFile(f)
failOn(err)
failOn(json.Unmarshal(d, &builds))
// Sort keys alphabetically (GoLang does not preserve the JSON order)
var keys []string
for n := range builds {
keys = append(keys, n)
}
sort.Strings(keys)
for _, n := range keys {
build := builds[n]
build.name = n
build.jsons = make(map[string]bool)
skip := true
for _, re := range r {
if re.MatchString(build.name) {
skip = false
break
}
}
if skip {
continue
}
log.Printf("Run %v", build.name)
build.jsons[f] = true
build.path = path.Dir(f)
// For each source file, assume we create an object file with the last char replaced
// with 'o'. We can get smarter later.
for _, v := range build.SourceFiles {
f := path.Base(v)
o := f[:len(f)-1] + "o"
build.ObjectFiles = appendIfMissing(build.ObjectFiles, o)
}
for _, v := range build.Include {
include(v, &build)
}
results = append(results, build)
}
return results
}
func buildkernel(b *build) {
if b.Kernel == nil {
return
}
envFunc := buildEnv(b)
for name, path := range b.Kernel.Ramfiles {
b.Kernel.Ramfiles[name] = os.Expand(path, envFunc);
}
codebuf := confcode(b.path, b.Kernel)
if b.Kernel.CodeFile == "" {
log.Fatalf("Missing Kernel.CodeFile in %v\n", b.path)
}
failOn(ioutil.WriteFile(b.Kernel.CodeFile, codebuf, 0666))
}
func wrapInQuote(args []string) []string {
var res []string
for _, a := range(args){
if strings.Contains(a, "=") {
res = append(res, "'" + a + "'")
} else {
res = append(res, a)
}
}
return res
}
func convertLibPathsToArgs(b *build) []string {
libLocations := make([]string, 0)
args := make([]string, 0)
defaultLibLocation := fromRoot("/arch/$ARCH/lib")
for _, lib := range b.Libs {
ldir := filepath.Dir(lib)
if ldir != defaultLibLocation {
if !isValueInList(ldir, libLocations) {
libLocations = append(libLocations, ldir)
args = append(args, "-L", ldir)
}
}
lib = strings.Replace(lib, ldir + "/lib", "-l", 1)
lib = strings.Replace(lib, ".a", "", 1)
args = append(args, lib)
}
return args
}
func compile(b *build) {
log.Printf("Building %s\n", b.name)
// N.B. Plan 9 has a very well defined include structure, just three things:
// /amd64/include, /sys/include, .
args := b.SourceFiles
args = append(args, b.Cflags...)
if !isValueInList("-c", b.Cflags) {
args = append(args, convertLibPathsToArgs(b)...)
args = append(args, b.Oflags...)
}
if len(b.SourceFilesCmd) > 0 {
for _, i := range b.SourceFilesCmd {
largs := make([]string, 3)
largs[0] = i
largs[1] = "-o"
largs[2] = strings.Replace(filepath.Base(i), filepath.Ext(i), "", 1)
cmd := exec.Command(tools["cc"], append(largs, args...)...)
run(b, *shellhack, cmd)
}
return
}
if !isValueInList("-c", b.Cflags) {
args = append(args, "-o", b.Program)
}
cmd := exec.Command(tools["cc"], args...)
run(b, *shellhack, cmd)
}
func link(b *build) {
if !isValueInList("-c", b.Cflags) {
return
}
log.Printf("Linking %s\n", b.name)
if len(b.SourceFilesCmd) > 0 {
for _, n := range b.SourceFilesCmd {
// Split off the last element of the file
var ext = filepath.Ext(n)
if len(ext) == 0 {
log.Fatalf("refusing to overwrite extension-less source file %v", n)
continue
}
n = n[:len(n)-len(ext)]
f := path.Base(n)
o := f[:len(f)] + ".o"
args := []string{"-o", n, o}
args = append(args, b.Oflags...)
args = append(args, b.Libs...)
run(b, *shellhack, exec.Command(tools["ld"], args...))
}
return
}
args := []string{"-o", b.Program}
args = append(args, b.ObjectFiles...)
args = append(args, b.Oflags...)
args = append(args, b.Libs...)
run(b, *shellhack, exec.Command(tools["ld"], args...))
}
func install(b *build) {
if b.Install == "" {
return
}
log.Printf("Installing %s\n", b.name)
failOn(os.MkdirAll(b.Install, 0755))
switch {
case len(b.SourceFilesCmd) > 0:
for _, n := range b.SourceFilesCmd {
ext := filepath.Ext(n)
exe := n[:len(n)-len(ext)]
move(exe, b.Install)
}
case len(b.Program) > 0:
move(b.Program, b.Install)
case len(b.Library) > 0:
ofiles := []string{}
for _, o := range b.ObjectFiles {
os.Rename(o, b.Library + "-" + o)
ofiles = append(ofiles, b.Library + "-" + o)
}
libpath := path.Join(b.Install, b.Library)
args := append([]string{"-rs", libpath}, ofiles...)
run(b, *shellhack, exec.Command(tools["ar"], args...))
run(b, *shellhack, exec.Command(tools["ranlib"], libpath))
}
}
func move(from, to string) {
final := path.Join(to, from)
log.Printf("move %s %s\n", from, final)
_ = os.Remove(final)
failOn(os.Link(from, final))
failOn(os.Remove(from))
}
func run(b *build, pipe bool, cmd *exec.Cmd) {
if b != nil {
cmd.Env = append(os.Environ(), b.Env...)
}
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
if pipe {
// Sh sends cmd to a shell. It's needed to enable $LD_PRELOAD tricks, see https://github.com/Harvey-OS/jehanne/issues/8#issuecomment-131235178
shell := exec.Command(tools["sh"])
shell.Env = cmd.Env
shell.Stderr = os.Stderr
shell.Stdout = os.Stdout
commandString := cmd.Args[0]
commandString += " " + strings.Join(wrapInQuote(cmd.Args[1:]), " ")
shStdin, err := shell.StdinPipe()
if err != nil {
log.Fatalf("cannot pipe [%v] to %s: %v", commandString, tools["sh"], err)
}
go func() {
defer shStdin.Close()
io.WriteString(shStdin, commandString)
}()
log.Printf("%q | %s\n", commandString, tools["sh"])
failOn(shell.Run())
return
}
log.Println(strings.Join(cmd.Args, " "))
failOn(cmd.Run())
}
func projects(b *build, r []*regexp.Regexp) {
for _, v := range b.Projects {
f, _ := findBuildfile(v)
log.Printf("Doing %s\n", f)
project(f, r, b)
}
}
// assumes we are in the wd of the project.
func project(bf string, which []*regexp.Regexp, container *build) {
cwd, err := os.Getwd()
failOn(err)
debug("Start new project cwd is %v", cwd)
defer os.Chdir(cwd)
dir := path.Dir(bf)
root := path.Base(bf)
debug("CD to %v and build using %v", dir, root)
failOn(os.Chdir(dir))
builds := process(root, which)
debug("Processing %v: %d target", root, len(builds))
for _, b := range builds {
debug("Processing %v: %v", b.name, b)
if container != nil {
b.Env = append(container.Env, b.Env...)
}
projects(&b, regexpAll)
for _, c := range b.Pre {
// this is a hack: we just pass the command through as an exec.Cmd
run(&b, true, exec.Command(c))
}
envFunc := buildEnv(&b);
b.Program = os.Expand(b.Program, envFunc)
for i, s := range b.SourceFiles {
b.SourceFiles[i] = fromRoot(os.Expand(s, envFunc));
}
for i, s := range b.SourceFilesCmd {
b.SourceFilesCmd[i] = fromRoot(os.Expand(s, envFunc));
}
for i, s := range b.ObjectFiles {
b.ObjectFiles[i] = fromRoot(os.Expand(s, envFunc));
}
buildkernel(&b)
if len(b.SourceFiles) > 0 || len(b.SourceFilesCmd) > 0 {
compile(&b)
}
if b.Program != "" || len(b.SourceFilesCmd) > 0 {
link(&b)
}
install(&b)
for _, c := range b.Post {
run(&b, true, exec.Command(c))
}
}
}
func main() {
// A small amount of setup is done in the paths*.go files. They are
// OS-specific path setup/manipulation. "jehanne" is set there and $PATH is
// adjusted.
var err error
findTools(os.Getenv("TOOLPREFIX"))
flag.Parse()
cwd, err = os.Getwd()
failOn(err)
a := os.Getenv("ARCH")
if a == "" || !arch[a] {
s := []string{}
for i := range arch {
s = append(s, i)
}
log.Fatalf("You need to set the ARCH environment variable from: %v", s)
}
// ensure this is exported, in case we used a default value
os.Setenv("JEHANNE", jehanne)
if os.Getenv("LD_PRELOAD") != "" {
log.Println("Using shellhack")
*shellhack = true
}
// If no args, assume 'build.json'
// Otherwise the first argument is either
// - the path to a json file
// - a directory containing a 'build.json' file
// - a regular expression to apply assuming 'build.json'
// Further arguments are regular expressions.
consumedArgs := 0;
bf := ""
if len(flag.Args()) == 0 {
f, err := findBuildfile("build.json")
failOn(err)
bf = f
} else {
f, err := findBuildfile(flag.Arg(0))
failOn(err)
if f == "" {
f, err := findBuildfile("build.json")
failOn(err)
bf = f
} else {
consumedArgs = 1
bf = f
}
}
re := []*regexp.Regexp{regexp.MustCompile(".")}
if len(flag.Args()) > consumedArgs {
re = re[:0]
for _, r := range flag.Args()[consumedArgs:] {
rx, err := regexp.Compile(r)
failOn(err)
re = append(re, rx)
}
}
project(bf, re, nil)
}
func findTools(toolprefix string) {
var err error
for k, v := range tools {
if x := os.Getenv(strings.ToUpper(k)); x != "" {
v = x
}
if toolprefix != "" && v != "sh" && !strings.Contains(v, toolprefix) {
v = toolprefix + v;
}
v, err = exec.LookPath(v)
failOn(err)
tools[k] = v
}
}
// disambiguate the buildfile argument
func findBuildfile(f string) (string, error) {
if strings.HasSuffix(f, ".json"){
if fi, err := os.Stat(f); err == nil && !fi.IsDir() {
return f, nil
}
return "", fmt.Errorf("unable to find buildfile %s", f)
}
if strings.Contains(f, "/") {
return findBuildfile(path.Join(f, "build.json"))
}
return "", nil
}