containerd/cmd/ctr/utils.go
Jess Valarezo 16855eedf7 ctr: move resolver to commands package
Signed-off-by: Jess Valarezo <valarezo.jessica@gmail.com>
2017-10-26 16:31:58 -04:00

83 lines
1.9 KiB
Go

package main
import (
"encoding/csv"
"fmt"
"strings"
specs "github.com/opencontainers/runtime-spec/specs-go"
)
// parseMountFlag parses a mount string in the form "type=foo,source=/path,destination=/target,options=rbind:rw"
func parseMountFlag(m string) (specs.Mount, error) {
mount := specs.Mount{}
r := csv.NewReader(strings.NewReader(m))
fields, err := r.Read()
if err != nil {
return mount, err
}
for _, field := range fields {
v := strings.Split(field, "=")
if len(v) != 2 {
return mount, fmt.Errorf("invalid mount specification: expected key=val")
}
key := v[0]
val := v[1]
switch key {
case "type":
mount.Type = val
case "source", "src":
mount.Source = val
case "destination", "dst":
mount.Destination = val
case "options":
mount.Options = strings.Split(val, ":")
default:
return mount, fmt.Errorf("mount option %q not supported", key)
}
}
return mount, nil
}
// replaceOrAppendEnvValues returns the defaults with the overrides either
// replaced by env key or appended to the list
func replaceOrAppendEnvValues(defaults, overrides []string) []string {
cache := make(map[string]int, len(defaults))
for i, e := range defaults {
parts := strings.SplitN(e, "=", 2)
cache[parts[0]] = i
}
for _, value := range overrides {
// Values w/o = means they want this env to be removed/unset.
if !strings.Contains(value, "=") {
if i, exists := cache[value]; exists {
defaults[i] = "" // Used to indicate it should be removed
}
continue
}
// Just do a normal set/update
parts := strings.SplitN(value, "=", 2)
if i, exists := cache[parts[0]]; exists {
defaults[i] = value
} else {
defaults = append(defaults, value)
}
}
// Now remove all entries that we want to "unset"
for i := 0; i < len(defaults); i++ {
if defaults[i] == "" {
defaults = append(defaults[:i], defaults[i+1:]...)
i--
}
}
return defaults
}