| #![allow(dead_code)] |
| #![unstable(feature = "process_internals", issue = "0")] |
| |
| use crate::collections::BTreeMap; |
| use crate::env; |
| use crate::ffi::{OsStr, OsString}; |
| use crate::sys::process::EnvKey; |
| |
| // Stores a set of changes to an environment |
| #[derive(Clone, Debug)] |
| pub struct CommandEnv { |
| clear: bool, |
| saw_path: bool, |
| vars: BTreeMap<EnvKey, Option<OsString>>, |
| } |
| |
| impl Default for CommandEnv { |
| fn default() -> Self { |
| CommandEnv { clear: false, saw_path: false, vars: Default::default() } |
| } |
| } |
| |
| impl CommandEnv { |
| // Capture the current environment with these changes applied |
| pub fn capture(&self) -> BTreeMap<EnvKey, OsString> { |
| let mut result = BTreeMap::<EnvKey, OsString>::new(); |
| if !self.clear { |
| for (k, v) in env::vars_os() { |
| result.insert(k.into(), v); |
| } |
| } |
| for (k, maybe_v) in &self.vars { |
| if let &Some(ref v) = maybe_v { |
| result.insert(k.clone(), v.clone()); |
| } else { |
| result.remove(k); |
| } |
| } |
| result |
| } |
| |
| // Apply these changes directly to the current environment |
| pub fn apply(&self) { |
| if self.clear { |
| for (k, _) in env::vars_os() { |
| env::remove_var(k); |
| } |
| } |
| for (key, maybe_val) in self.vars.iter() { |
| if let &Some(ref val) = maybe_val { |
| env::set_var(key, val); |
| } else { |
| env::remove_var(key); |
| } |
| } |
| } |
| |
| pub fn is_unchanged(&self) -> bool { |
| !self.clear && self.vars.is_empty() |
| } |
| |
| pub fn capture_if_changed(&self) -> Option<BTreeMap<EnvKey, OsString>> { |
| if self.is_unchanged() { None } else { Some(self.capture()) } |
| } |
| |
| // The following functions build up changes |
| pub fn set(&mut self, key: &OsStr, value: &OsStr) { |
| self.maybe_saw_path(&key); |
| self.vars.insert(key.to_owned().into(), Some(value.to_owned())); |
| } |
| |
| pub fn remove(&mut self, key: &OsStr) { |
| self.maybe_saw_path(&key); |
| if self.clear { |
| self.vars.remove(key); |
| } else { |
| self.vars.insert(key.to_owned().into(), None); |
| } |
| } |
| |
| pub fn clear(&mut self) { |
| self.clear = true; |
| self.vars.clear(); |
| } |
| |
| pub fn have_changed_path(&self) -> bool { |
| self.saw_path || self.clear |
| } |
| |
| fn maybe_saw_path(&mut self, key: &OsStr) { |
| if !self.saw_path && key == "PATH" { |
| self.saw_path = true; |
| } |
| } |
| } |