refact: terminal, win, run as admin (#12300)

Signed-off-by: fufesou <linlong1266@gmail.com>

src/flutter_ffi.rs

@@ -138,7 +138,7 @@ pub fn session_add_sync(
     is_shared_password: bool,
     conn_token: Option<String>,
 ) -> SyncReturn<String> {
-    if let Err(e) = session_add(
+    let add_res = session_add(
         &session_id,
         &id,
         is_file_transfer,
@@ -151,7 +151,14 @@ pub fn session_add_sync(
         password,
         is_shared_password,
         conn_token,
-    ) {
+    );
+    // We can't put the remove call together with `std::env::var("IS_TERMINAL_ADMIN")`.
+    // Because there are some `bail!` in `session_add()`, we must make sure `IS_TERMINAL_ADMIN` is removed at last.
+    if is_terminal {
+        std::env::remove_var("IS_TERMINAL_ADMIN");
+    }
+
+    if let Err(e) = add_res {
         SyncReturn(format!("Failed to add session with id {}, {}", &id, e))
     } else {
         SyncReturn("".to_owned())
@@ -1067,6 +1074,35 @@ pub fn main_get_env(key: String) -> SyncReturn<String> {
     SyncReturn(std::env::var(key).unwrap_or_default())
 }
 
+// Dart does not support changing environment variables.
+// `Platform.environment['MY_VAR'] = 'VAR';` will throw an error
+// `Unsupported operation: Cannot modify unmodifiable map`.
+//
+// And we need to share the environment variables between rust and dart isolates sometimes.
+pub fn main_set_env(key: String, value: Option<String>) -> SyncReturn<()> {
+    let is_valid_key = !key.is_empty() && !key.contains('=') && !key.contains('\0');
+    debug_assert!(is_valid_key, "Invalid environment variable key: {}", key);
+    if !is_valid_key {
+        log::error!("Invalid environment variable key: {}", key);
+        return SyncReturn(());
+    }
+
+    match value {
+        Some(v) => {
+            let is_valid_value = !v.contains('\0');
+            debug_assert!(is_valid_value, "Invalid environment variable value: {}", v);
+            if !is_valid_value {
+                log::error!("Invalid environment variable value: {}", v);
+                return SyncReturn(());
+            }
+            std::env::set_var(key, v);
+        }
+        None => std::env::remove_var(key),
+    }
+
+    SyncReturn(())
+}
+
 pub fn main_set_local_option(key: String, value: String) {
     let is_texture_render_key = key.eq(config::keys::OPTION_TEXTURE_RENDER);
     let is_d3d_render_key = key.eq(config::keys::OPTION_ALLOW_D3D_RENDER);