1
0
Fork 0
mirror of https://github.com/moby/moby.git synced 2022-11-09 12:21:53 -05:00
moby--moby/runconfig/opts/opts.go
Michael Crosby ee3ac3aa66 Add init process for zombie fighting
This adds a small C binary for fighting zombies.  It is mounted under
`/dev/init` and is prepended to the args specified by the user.  You
enable it via a daemon flag, `dockerd --init`, as it is disable by
default for backwards compat.

You can also override the daemon option or specify this on a per
container basis with `docker run --init=true|false`.

You can test this by running a process like this as the pid 1 in a
container and see the extra zombie that appears in the container as it
is running.

```c

int main(int argc, char ** argv) {
	pid_t pid = fork();
	if (pid == 0) {
		pid = fork();
		if (pid == 0) {
			exit(0);
		}
		sleep(3);
		exit(0);
	}
	printf("got pid %d and exited\n", pid);
	sleep(20);
}
```

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
2016-09-19 17:33:50 -07:00

86 lines
2.3 KiB
Go

package opts
import (
"fmt"
"net"
"os"
"strings"
fopts "github.com/docker/docker/opts"
)
// ValidateAttach validates that the specified string is a valid attach option.
func ValidateAttach(val string) (string, error) {
s := strings.ToLower(val)
for _, str := range []string{"stdin", "stdout", "stderr"} {
if s == str {
return s, nil
}
}
return val, fmt.Errorf("valid streams are STDIN, STDOUT and STDERR")
}
// ValidateEnv validates an environment variable and returns it.
// If no value is specified, it returns the current value using os.Getenv.
//
// As on ParseEnvFile and related to #16585, environment variable names
// are not validate what so ever, it's up to application inside docker
// to validate them or not.
func ValidateEnv(val string) (string, error) {
arr := strings.Split(val, "=")
if len(arr) > 1 {
return val, nil
}
if !doesEnvExist(val) {
return val, nil
}
return fmt.Sprintf("%s=%s", val, os.Getenv(val)), nil
}
func doesEnvExist(name string) bool {
for _, entry := range os.Environ() {
parts := strings.SplitN(entry, "=", 2)
if parts[0] == name {
return true
}
}
return false
}
// ValidateArg validates a build-arg variable and returns it.
// Build-arg is in the form of <varname>=<value> where <varname> is required.
func ValidateArg(val string) (string, error) {
arr := strings.Split(val, "=")
if len(arr) > 1 && isNotEmpty(arr[0]) {
return val, nil
}
return "", fmt.Errorf("bad format for build-arg: %s", val)
}
func isNotEmpty(val string) bool {
return len(val) > 0
}
// ValidateExtraHost validates that the specified string is a valid extrahost and returns it.
// ExtraHost is in the form of name:ip where the ip has to be a valid ip (IPv4 or IPv6).
func ValidateExtraHost(val string) (string, error) {
// allow for IPv6 addresses in extra hosts by only splitting on first ":"
arr := strings.SplitN(val, ":", 2)
if len(arr) != 2 || len(arr[0]) == 0 {
return "", fmt.Errorf("bad format for add-host: %q", val)
}
if _, err := fopts.ValidateIPAddress(arr[1]); err != nil {
return "", fmt.Errorf("invalid IP address in add-host: %q", arr[1])
}
return val, nil
}
// ValidateMACAddress validates a MAC address.
func ValidateMACAddress(val string) (string, error) {
_, err := net.ParseMAC(strings.TrimSpace(val))
if err != nil {
return "", err
}
return val, nil
}