Ben Konyi
8d41c9b677
Avoid a race condition between async setenv/unsetenv calls on the VM thread and concurrent getenv/environ reads on the main thread. In glibc, setenv and getenv are not thread-safe against each other. VmInteropHandler.setEnvironmentVariable previously sent a message to the VM thread to call setenv/unsetenv asynchronously, while the main thread immediately proceeded to access Platform.environment or Platform.localeName (which calls getenv). This could cause a crash (SIGSEGV) in getenv. This CL makes VmInteropHandler.setEnvironmentVariable synchronous by awaiting a reply from the VM thread before returning. TEST=pkg/dartdev/test/environment_test.dart Fixes https://github.com/dart-lang/sdk/issues/63460 Change-Id: Ic8211897ce26ffbdc142fa594cd397189a61f061 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/506800 Commit-Queue: Ben Konyi <bkonyi@google.com> Reviewed-by: Ryan Macnak <rmacnak@google.com> Auto-Submit: Ben Konyi <bkonyi@google.com>