blob: 9feddd00c4b4d018e68fed15380c2a3be4bcd17d [file] [log] [blame] [edit]
// Copyright 2016 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.
// +build ignore
// mkpost processes the output of cgo -godefs to
// modify the generated types. It is used to clean up
// the sys API in an architecture specific manner.
//
// mkpost is run after cgo -godefs; see README.md.
package main
import (
"bytes"
"fmt"
"go/format"
"io/ioutil"
"log"
"os"
"regexp"
)
func main() {
// Get the OS and architecture (using GOARCH_TARGET if it exists)
goos := os.Getenv("GOOS")
goarch := os.Getenv("GOARCH_TARGET")
if goarch == "" {
goarch = os.Getenv("GOARCH")
}
// Check that we are using the Docker-based build system if we should be.
if goos == "linux" {
if os.Getenv("GOLANG_SYS_BUILD") != "docker" {
os.Stderr.WriteString("In the Docker-based build system, mkpost should not be called directly.\n")
os.Stderr.WriteString("See README.md\n")
os.Exit(1)
}
}
b, err := ioutil.ReadAll(os.Stdin)
if err != nil {
log.Fatal(err)
}
// Intentionally export __val fields in Fsid and Sigset_t
valRegex := regexp.MustCompile(`type (Fsid|Sigset_t) struct {(\s+)X__val(\s+\S+\s+)}`)
b = valRegex.ReplaceAll(b, []byte("type $1 struct {${2}Val$3}"))
// Intentionally export __fds_bits field in FdSet
fdSetRegex := regexp.MustCompile(`type (FdSet) struct {(\s+)X__fds_bits(\s+\S+\s+)}`)
b = fdSetRegex.ReplaceAll(b, []byte("type $1 struct {${2}Bits$3}"))
// If we have empty Ptrace structs, we should delete them. Only s390x emits
// nonempty Ptrace structs.
ptraceRexexp := regexp.MustCompile(`type Ptrace((Psw|Fpregs|Per) struct {\s*})`)
b = ptraceRexexp.ReplaceAll(b, nil)
// Replace the control_regs union with a blank identifier for now.
controlRegsRegex := regexp.MustCompile(`(Control_regs)\s+\[0\]uint64`)
b = controlRegsRegex.ReplaceAll(b, []byte("_ [0]uint64"))
// Remove fields that are added by glibc
// Note that this is unstable as the identifers are private.
removeFieldsRegex := regexp.MustCompile(`X__glibc\S*`)
b = removeFieldsRegex.ReplaceAll(b, []byte("_"))
// Convert [65]int8 to [65]byte in Utsname members to simplify
// conversion to string; see golang.org/issue/20753
convertUtsnameRegex := regexp.MustCompile(`((Sys|Node|Domain)name|Release|Version|Machine)(\s+)\[(\d+)\]u?int8`)
b = convertUtsnameRegex.ReplaceAll(b, []byte("$1$3[$4]byte"))
// Convert [1024]int8 to [1024]byte in Ptmget members
convertPtmget := regexp.MustCompile(`([SC]n)(\s+)\[(\d+)\]u?int8`)
b = convertPtmget.ReplaceAll(b, []byte("$1[$3]byte"))
// Remove spare fields (e.g. in Statx_t)
spareFieldsRegex := regexp.MustCompile(`X__spare\S*`)
b = spareFieldsRegex.ReplaceAll(b, []byte("_"))
// Remove cgo padding fields
removePaddingFieldsRegex := regexp.MustCompile(`Pad_cgo_\d+`)
b = removePaddingFieldsRegex.ReplaceAll(b, []byte("_"))
// Remove padding, hidden, or unused fields
removeFieldsRegex = regexp.MustCompile(`\b(X_\S+|Padding)`)
b = removeFieldsRegex.ReplaceAll(b, []byte("_"))
// Remove the first line of warning from cgo
b = b[bytes.IndexByte(b, '\n')+1:]
// Modify the command in the header to include:
// mkpost, our own warning, and a build tag.
replacement := fmt.Sprintf(`$1 | go run mkpost.go
// Code generated by the command above; see README.md. DO NOT EDIT.
// +build %s,%s`, goarch, goos)
cgoCommandRegex := regexp.MustCompile(`(cgo -godefs .*)`)
b = cgoCommandRegex.ReplaceAll(b, []byte(replacement))
// gofmt
b, err = format.Source(b)
if err != nil {
log.Fatal(err)
}
os.Stdout.Write(b)
}