moby/container/env.go
Daniel Nephin 4f0d95fa6e Add canonical import comment
Signed-off-by: Daniel Nephin <dnephin@docker.com>
2018-02-05 16:51:57 -05:00

43 lines
1.1 KiB
Go

package container // import "github.com/docker/docker/container"
import (
"strings"
)
// 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
}