blob: dc6177c122d9399da6f647ff70f02c44e92bc6f8 [file] [log] [blame]
// Copyright 2018 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 packagesdriver fetches type sizes for go/packages and go/analysis.
package packagesdriver
import (
"bytes"
"context"
"encoding/json"
"fmt"
"go/types"
"os/exec"
"strings"
"golang.org/x/tools/internal/gocommand"
)
var debug = false
func GetSizes(ctx context.Context, buildFlags, env []string, gocmdRunner *gocommand.Runner, dir string) (types.Sizes, error) {
// TODO(matloob): Clean this up. This code is mostly a copy of packages.findExternalDriver.
const toolPrefix = "GOPACKAGESDRIVER="
tool := ""
for _, env := range env {
if val := strings.TrimPrefix(env, toolPrefix); val != env {
tool = val
}
}
if tool == "" {
var err error
tool, err = exec.LookPath("gopackagesdriver")
if err != nil {
// We did not find the driver, so use "go list".
tool = "off"
}
}
if tool == "off" {
return GetSizesGolist(ctx, buildFlags, env, gocmdRunner, dir)
}
req, err := json.Marshal(struct {
Command string `json:"command"`
Env []string `json:"env"`
BuildFlags []string `json:"build_flags"`
}{
Command: "sizes",
Env: env,
BuildFlags: buildFlags,
})
if err != nil {
return nil, fmt.Errorf("failed to encode message to driver tool: %v", err)
}
buf := new(bytes.Buffer)
cmd := exec.CommandContext(ctx, tool)
cmd.Dir = dir
cmd.Env = env
cmd.Stdin = bytes.NewReader(req)
cmd.Stdout = buf
cmd.Stderr = new(bytes.Buffer)
if err := cmd.Run(); err != nil {
return nil, fmt.Errorf("%v: %v: %s", tool, err, cmd.Stderr)
}
var response struct {
// Sizes, if not nil, is the types.Sizes to use when type checking.
Sizes *types.StdSizes
}
if err := json.Unmarshal(buf.Bytes(), &response); err != nil {
return nil, err
}
return response.Sizes, nil
}
func GetSizesGolist(ctx context.Context, buildFlags, env []string, gocmdRunner *gocommand.Runner, dir string) (types.Sizes, error) {
inv := gocommand.Invocation{
Verb: "list",
Args: []string{"-f", "{{context.GOARCH}} {{context.Compiler}}", "--", "unsafe"},
Env: env,
BuildFlags: buildFlags,
WorkingDir: dir,
}
stdout, stderr, friendlyErr, rawErr := gocmdRunner.RunRaw(ctx, inv)
var goarch, compiler string
if rawErr != nil {
if strings.Contains(rawErr.Error(), "cannot find main module") {
// User's running outside of a module. All bets are off. Get GOARCH and guess compiler is gc.
// TODO(matloob): Is this a problem in practice?
inv := gocommand.Invocation{
Verb: "env",
Args: []string{"GOARCH"},
Env: env,
WorkingDir: dir,
}
envout, enverr := gocmdRunner.Run(ctx, inv)
if enverr != nil {
return nil, enverr
}
goarch = strings.TrimSpace(envout.String())
compiler = "gc"
} else {
return nil, friendlyErr
}
} else {
fields := strings.Fields(stdout.String())
if len(fields) < 2 {
return nil, fmt.Errorf("could not parse GOARCH and Go compiler in format \"<GOARCH> <compiler>\":\nstdout: <<%s>>\nstderr: <<%s>>",
stdout.String(), stderr.String())
}
goarch = fields[0]
compiler = fields[1]
}
return types.SizesFor(compiler, goarch), nil
}