1// Copyright 2020 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
5package goobj
6
7import (
8	"bufio"
9	"bytes"
10	"fmt"
11	"internal/buildcfg"
12	"internal/testenv"
13	"os"
14	"testing"
15
16	"cmd/internal/bio"
17	"cmd/internal/objabi"
18)
19
20func dummyWriter(buf *bytes.Buffer) *Writer {
21	wr := &bio.Writer{Writer: bufio.NewWriter(buf)} // hacky: no file, so cannot seek
22	return NewWriter(wr)
23}
24
25func TestReadWrite(t *testing.T) {
26	// Test that we get the same data in a write-read roundtrip.
27
28	// Write a symbol, a relocation, and an aux info.
29	var buf bytes.Buffer
30	w := dummyWriter(&buf)
31
32	var s Sym
33	s.SetABI(1)
34	s.SetType(uint8(objabi.STEXT))
35	s.SetFlag(0x12)
36	s.SetSiz(12345)
37	s.SetAlign(8)
38	s.Write(w)
39
40	var r Reloc
41	r.SetOff(12)
42	r.SetSiz(4)
43	r.SetType(uint16(objabi.R_ADDR))
44	r.SetAdd(54321)
45	r.SetSym(SymRef{11, 22})
46	r.Write(w)
47
48	var a Aux
49	a.SetType(AuxFuncInfo)
50	a.SetSym(SymRef{33, 44})
51	a.Write(w)
52
53	w.wr.Flush()
54
55	// Read them back and check.
56	b := buf.Bytes()
57	var s2 Sym
58	s2.fromBytes(b)
59	if s2.ABI() != 1 || s2.Type() != uint8(objabi.STEXT) || s2.Flag() != 0x12 || s2.Siz() != 12345 || s2.Align() != 8 {
60		t.Errorf("read Sym2 mismatch: got %v %v %v %v %v", s2.ABI(), s2.Type(), s2.Flag(), s2.Siz(), s2.Align())
61	}
62
63	b = b[SymSize:]
64	var r2 Reloc
65	r2.fromBytes(b)
66	if r2.Off() != 12 || r2.Siz() != 4 || r2.Type() != uint16(objabi.R_ADDR) || r2.Add() != 54321 || r2.Sym() != (SymRef{11, 22}) {
67		t.Errorf("read Reloc2 mismatch: got %v %v %v %v %v", r2.Off(), r2.Siz(), r2.Type(), r2.Add(), r2.Sym())
68	}
69
70	b = b[RelocSize:]
71	var a2 Aux
72	a2.fromBytes(b)
73	if a2.Type() != AuxFuncInfo || a2.Sym() != (SymRef{33, 44}) {
74		t.Errorf("read Aux2 mismatch: got %v %v", a2.Type(), a2.Sym())
75	}
76}
77
78var issue41621prolog = `
79package main
80var lines = []string{
81`
82
83var issue41621epilog = `
84}
85func getLines() []string {
86	return lines
87}
88func main() {
89	println(getLines())
90}
91`
92
93func TestIssue41621LargeNumberOfRelocations(t *testing.T) {
94	if testing.Short() || (buildcfg.GOARCH != "amd64") {
95		t.Skipf("Skipping large number of relocations test in short mode or on %s", buildcfg.GOARCH)
96	}
97	testenv.MustHaveGoBuild(t)
98
99	tmpdir, err := os.MkdirTemp("", "lotsofrelocs")
100	if err != nil {
101		t.Fatalf("can't create temp directory: %v\n", err)
102	}
103	defer os.RemoveAll(tmpdir)
104
105	// Emit testcase.
106	var w bytes.Buffer
107	fmt.Fprintf(&w, issue41621prolog)
108	for i := 0; i < 1048576+13; i++ {
109		fmt.Fprintf(&w, "\t\"%d\",\n", i)
110	}
111	fmt.Fprintf(&w, issue41621epilog)
112	err = os.WriteFile(tmpdir+"/large.go", w.Bytes(), 0666)
113	if err != nil {
114		t.Fatalf("can't write output: %v\n", err)
115	}
116
117	// Emit go.mod
118	w.Reset()
119	fmt.Fprintf(&w, "module issue41621\n\ngo 1.12\n")
120	err = os.WriteFile(tmpdir+"/go.mod", w.Bytes(), 0666)
121	if err != nil {
122		t.Fatalf("can't write output: %v\n", err)
123	}
124	w.Reset()
125
126	// Build.
127	cmd := testenv.Command(t, testenv.GoToolPath(t), "build", "-o", "large")
128	cmd.Dir = tmpdir
129	out, err := cmd.CombinedOutput()
130	if err != nil {
131		t.Fatalf("Build failed: %v, output: %s", err, out)
132	}
133}
134