From 4e2456bc0977b5510f9c35610f0c2d89ce9cd3c3 Mon Sep 17 00:00:00 2001
From: Dan Willemsen <dwillemsen@google.com>
Date: Thu, 3 Oct 2019 16:45:58 -0700
Subject: [PATCH] Fix dumpvars $PATH / $TMPDIR

Instead of just using the host $PATH during dumpvars, use our path
configuration from the regular build. But instead of creating a ton of
symlinks to the interposer, just use a small directory of symlinks. This
only takes ~3ms (vs ~300ms), at the expense of error logging. Since we
do just about the same product configuration at the start of the build,
we can just rely on the logging there.

This fixes warnings printed by the Mac build, since we using the host
`date` instead of the toybox version:

usage: date [-jnRu] [-d dst] [-r seconds] [-t west] [-v[+|-]val[ymwdHMS]] ...
            [-f fmt date | [[[mm]dd]HH]MM[[cc]yy][.ss]] [+format]
usage: date [-jnRu] [-d dst] [-r seconds] [-t west] [-v[+|-]val[ymwdHMS]] ...
            [-f fmt date | [[[mm]dd]HH]MM[[cc]yy][.ss]] [+format]

TMPDIR was being shared with the main build, but we're allowed to run in
parallel. If a build is started while we're running, our TMPDIR may be
cleared. Instead, create our own temporary directory, which doesn't need
to be a stable value (as we never do caching here).

Fixes: 141893400
Test: (on mac) source build/envsetup.sh; lunch
Change-Id: I0ff536e71dc5649cae26daa0087eb80861704021
---
 ui/build/dumpvars.go | 14 +++++++++++++-
 ui/build/path.go     | 46 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+), 1 deletion(-)

diff --git a/ui/build/dumpvars.go b/ui/build/dumpvars.go
index 82b275010..1925e87b9 100644
--- a/ui/build/dumpvars.go
+++ b/ui/build/dumpvars.go
@@ -17,6 +17,8 @@ package build
 import (
 	"bytes"
 	"fmt"
+	"io/ioutil"
+	"os"
 	"strings"
 
 	"android/soong/ui/metrics"
@@ -51,7 +53,17 @@ func DumpMakeVars(ctx Context, config Config, goals, vars []string) (map[string]
 
 	var ret map[string]string
 	if len(makeVars) > 0 {
-		var err error
+		tmpDir, err := ioutil.TempDir("", "dumpvars")
+		if err != nil {
+			return nil, err
+		}
+		defer os.RemoveAll(tmpDir)
+
+		// It's not safe to use the same TMPDIR as the build, as that can be removed.
+		config.Environment().Set("TMPDIR", tmpDir)
+
+		SetupLitePath(ctx, config)
+
 		ret, err = dumpMakeVars(ctx, config, goals, makeVars, false)
 		if err != nil {
 			return ret, err
diff --git a/ui/build/path.go b/ui/build/path.go
index 0e1c02cac..c34ba1b52 100644
--- a/ui/build/path.go
+++ b/ui/build/path.go
@@ -18,6 +18,7 @@ import (
 	"fmt"
 	"io/ioutil"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"runtime"
 	"strings"
@@ -53,6 +54,51 @@ func parsePathDir(dir string) []string {
 	return ret
 }
 
+// A "lite" version of SetupPath used for dumpvars, or other places that need
+// minimal overhead (but at the expense of logging).
+func SetupLitePath(ctx Context, config Config) {
+	if config.pathReplaced {
+		return
+	}
+
+	ctx.BeginTrace(metrics.RunSetupTool, "litepath")
+	defer ctx.EndTrace()
+
+	origPath, _ := config.Environment().Get("PATH")
+	myPath, _ := config.Environment().Get("TMPDIR")
+	myPath = filepath.Join(myPath, "path")
+	ensureEmptyDirectoriesExist(ctx, myPath)
+
+	os.Setenv("PATH", origPath)
+	for name, pathConfig := range paths.Configuration {
+		if !pathConfig.Symlink {
+			continue
+		}
+
+		origExec, err := exec.LookPath(name)
+		if err != nil {
+			continue
+		}
+		origExec, err = filepath.Abs(origExec)
+		if err != nil {
+			continue
+		}
+
+		err = os.Symlink(origExec, filepath.Join(myPath, name))
+		if err != nil {
+			ctx.Fatalln("Failed to create symlink:", err)
+		}
+	}
+
+	myPath, _ = filepath.Abs(myPath)
+
+	prebuiltsPath, _ := filepath.Abs("prebuilts/build-tools/path/" + runtime.GOOS + "-x86")
+	myPath = prebuiltsPath + string(os.PathListSeparator) + myPath
+
+	config.Environment().Set("PATH", myPath)
+	config.pathReplaced = true
+}
+
 func SetupPath(ctx Context, config Config) {
 	if config.pathReplaced {
 		return