Golang结构体知识

1 container.Lock()

1 // container/container.go
 2 type Container struct {
 3     StreamConfig *stream.Config
 4     // embed for Container to support states directly.
 5     *State          `json:"State"`          // Needed for Engine API version <= 1.11
 6     Root            string                  `json:"-"` // Path to the "home" of the container, including metadata.
 7     BaseFS          containerfs.ContainerFS `json:"-"` // interface containing graphdriver mount
 8     RWLayer         layer.RWLayer           `json:"-"`
 9     ....   
10 }
11 
12 // container/state.go
13 type State struct {
14     sync.Mutex
15     // Note that `Running` and `Paused` are not mutually exclusive:
16     // When pausing a container (on Linux), the cgroups freezer is used to suspend
17     // all processes in the container. Freezing the process requires the process to
18     // be running. As a result, paused containers are both `Running` _and_ `Paused`.
19     Running           bool
20     Paused            bool
21     Restarting        bool
22     OOMKilled         bool
23     RemovalInProgress bool // Not need for this to be persistent on disk.
24     Dead              bool
25     Pid               int
26     ExitCodeValue     int    `json:"ExitCode"`
27     ErrorMsg          string `json:"Error"` // contains last known error during container start, stop, or remove
28     StartedAt         time.Time
29     FinishedAt        time.Time
30     Health            *Health
31 
32     waitStop   chan struct{}
33     waitRemove chan struct{}
34 }

 1 package main
 2 
 3 import (
 4     "fmt"
 5     "sync"
 6 )
 7 
 8 type State struct {
 9     sync.Mutex
10     Running bool
11     Paused bool
12 }
13 
14 type Container struct {
15     *State
16     ID string
17 }
18 
19 func NewState() *State {
20     return &State{
21         Running: false,
22         Paused: false,
23     }
24 }
25 
26 func (c *Container) getInfo() error {
27     c.Lock()
28     defer c.Unlock()  // defer 可以另写一篇文章说一下
29     fmt.Println("container is locked")
30     return nil
31 }
32 
33 func main() {
34     c := Container{State: NewState()}
35     c.getInfo()
36
37    c.Lock()
38     fmt.Println("second lock")
39     c.Unlock()
40 }