1// Copyright 2016 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5//go:build ignore
6
7// mkpost processes the output of cgo -godefs to
8// modify the generated types. It is used to clean up
9// the syscall API in an architecture specific manner.
10//
11// mkpost is run after cgo -godefs by mkall.sh.
12package main
13
14import (
15	"fmt"
16	"go/format"
17	"io"
18	"log"
19	"os"
20	"regexp"
21	"strings"
22)
23
24func main() {
25	b, err := io.ReadAll(os.Stdin)
26	if err != nil {
27		log.Fatal(err)
28	}
29	s := string(b)
30
31	goarch := os.Getenv("GOARCH")
32	goos := os.Getenv("GOOS")
33	switch {
34	case goarch == "s390x" && goos == "linux":
35		// Export the types of PtraceRegs fields.
36		re := regexp.MustCompile("ptrace(Psw|Fpregs|Per)")
37		s = re.ReplaceAllString(s, "Ptrace$1")
38
39		// Replace padding fields inserted by cgo with blank identifiers.
40		re = regexp.MustCompile("Pad_cgo[A-Za-z0-9_]*")
41		s = re.ReplaceAllString(s, "_")
42
43		// We want to keep the X_ fields that are already consistently exported
44		// for the other linux GOARCH settings.
45		// Hide them and restore later.
46		s = strings.Replace(s, "X__val", "MKPOSTFSIDVAL", 1)
47		s = strings.Replace(s, "X__ifi_pad", "MKPOSTIFIPAD", 1)
48		s = strings.Replace(s, "X_f", "MKPOSTSYSINFOTF", 1)
49
50		// Replace other unwanted fields with blank identifiers.
51		re = regexp.MustCompile("X_[A-Za-z0-9_]*")
52		s = re.ReplaceAllString(s, "_")
53
54		// Restore preserved fields.
55		s = strings.Replace(s, "MKPOSTFSIDVAL", "X__val", 1)
56		s = strings.Replace(s, "MKPOSTIFIPAD", "X__ifi_pad", 1)
57		s = strings.Replace(s, "MKPOSTSYSINFOTF", "X_f", 1)
58
59		// Force the type of RawSockaddr.Data to [14]int8 to match
60		// the existing gccgo API.
61		re = regexp.MustCompile("(Data\\s+\\[14\\])uint8")
62		s = re.ReplaceAllString(s, "${1}int8")
63
64	case goos == "freebsd":
65		// Keep pre-FreeBSD 10 / non-POSIX 2008 names for timespec fields
66		re := regexp.MustCompile("(A|M|C|Birth)tim\\s+Timespec")
67		s = re.ReplaceAllString(s, "${1}timespec Timespec")
68	}
69
70	// gofmt
71	b, err = format.Source([]byte(s))
72	if err != nil {
73		log.Fatal(err)
74	}
75
76	// Append this command to the header to show where the new file
77	// came from.
78	re := regexp.MustCompile("(cgo -godefs [a-zA-Z0-9_]+\\.go.*)")
79	s = re.ReplaceAllString(string(b), "$1 | go run mkpost.go")
80
81	fmt.Print(s)
82}
83