1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
|
package pidfile
import (
"errors"
"os"
"os/exec"
"path/filepath"
"runtime"
"strconv"
"testing"
)
func TestWrite(t *testing.T) {
path := filepath.Join(t.TempDir(), "testfile")
err := Write(path, 0)
if err == nil {
t.Fatal("writing PID < 1 should fail")
}
err = Write(path, os.Getpid())
if err != nil {
t.Fatal("Could not create test file", err)
}
err = Write(path, os.Getpid())
if err == nil {
t.Error("Test file creation not blocked")
}
pid, err := Read(path)
if err != nil {
t.Error(err)
}
if pid != os.Getpid() {
t.Errorf("expected pid %d, got %d", os.Getpid(), pid)
}
}
func TestRead(t *testing.T) {
tmpDir := t.TempDir()
t.Run("non-existing pidFile", func(t *testing.T) {
_, err := Read(filepath.Join(tmpDir, "nosuchfile"))
if !errors.Is(err, os.ErrNotExist) {
t.Errorf("expected an os.ErrNotExist, got: %+v", err)
}
})
// Verify that we ignore a malformed PID in the file.
t.Run("malformed pid", func(t *testing.T) {
// Not using Write here, to test Read in isolation.
pidFile := filepath.Join(tmpDir, "pidfile-malformed")
err := os.WriteFile(pidFile, []byte("something that's not an integer"), 0o644)
if err != nil {
t.Fatal(err)
}
pid, err := Read(pidFile)
if err != nil {
t.Error(err)
}
if pid != 0 {
t.Errorf("expected pid %d, got %d", 0, pid)
}
})
t.Run("zero pid", func(t *testing.T) {
// Not using Write here, to test Read in isolation.
pidFile := filepath.Join(tmpDir, "pidfile-zero")
err := os.WriteFile(pidFile, []byte(strconv.Itoa(0)), 0o644)
if err != nil {
t.Fatal(err)
}
pid, err := Read(pidFile)
if err != nil {
t.Error(err)
}
if pid != 0 {
t.Errorf("expected pid %d, got %d", 0, pid)
}
})
t.Run("negative pid", func(t *testing.T) {
// Not using Write here, to test Read in isolation.
pidFile := filepath.Join(tmpDir, "pidfile-negative")
err := os.WriteFile(pidFile, []byte(strconv.Itoa(-1)), 0o644)
if err != nil {
t.Fatal(err)
}
pid, err := Read(pidFile)
if err != nil {
t.Error(err)
}
if pid != 0 {
t.Errorf("expected pid %d, got %d", 0, pid)
}
})
t.Run("current process pid", func(t *testing.T) {
// Not using Write here, to test Read in isolation.
pidFile := filepath.Join(tmpDir, "pidfile")
err := os.WriteFile(pidFile, []byte(strconv.Itoa(os.Getpid())), 0o644)
if err != nil {
t.Fatal(err)
}
pid, err := Read(pidFile)
if err != nil {
t.Error(err)
}
if pid != os.Getpid() {
t.Errorf("expected pid %d, got %d", os.Getpid(), pid)
}
})
// Verify that we don't return a PID if the process exited.
t.Run("exited process", func(t *testing.T) {
if runtime.GOOS == "windows" {
t.Skip("TODO: make this work on Windows")
}
// Get a PID of an exited process.
cmd := exec.Command("echo", "hello world")
err := cmd.Run()
if err != nil {
t.Fatal(err)
}
exitedPID := cmd.ProcessState.Pid()
// Not using Write here, to test Read in isolation.
pidFile := filepath.Join(tmpDir, "pidfile-exited")
err = os.WriteFile(pidFile, []byte(strconv.Itoa(exitedPID)), 0o644)
if err != nil {
t.Fatal(err)
}
pid, err := Read(pidFile)
if err != nil {
t.Error(err)
}
if pid != 0 {
t.Errorf("expected pid %d, got %d", 0, pid)
}
})
}
|
