From 7af29abbc1c2531d4172a9c69f250007c2ff1037 Mon Sep 17 00:00:00 2001
From: Camelid <camelidcamel@gmail.com>
Date: Sun, 10 Jan 2021 13:16:06 -0800
Subject: [PATCH] log-color: Detect TTY based on stderr, not stdout
Logging goes to stderr, not stdout, so we should base our automated
detection on stderr instead of stdout.
Thanks to Ralf Jung for noticing and reporting the bug!
---
compiler/rustc_driver/src/lib.rs | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/compiler/rustc_driver/src/lib.rs b/compiler/rustc_driver/src/lib.rs
index d57ab2433ad..c2a0d8ef7ea 100644
--- a/compiler/rustc_driver/src/lib.rs
+++ b/compiler/rustc_driver/src/lib.rs
@@ -566,6 +566,25 @@ fn stdout_isatty() -> bool {
}
}
+// FIXME remove these and use winapi 0.3 instead
+#[cfg(unix)]
+fn stderr_isatty() -> bool {
+ unsafe { libc::isatty(libc::STDERR_FILENO) != 0 }
+}
+
+#[cfg(windows)]
+fn stderr_isatty() -> bool {
+ use winapi::um::consoleapi::GetConsoleMode;
+ use winapi::um::processenv::GetStdHandle;
+ use winapi::um::winbase::STD_ERROR_HANDLE;
+
+ unsafe {
+ let handle = GetStdHandle(STD_ERROR_HANDLE);
+ let mut out = 0;
+ GetConsoleMode(handle, &mut out) != 0
+ }
+}
+
fn handle_explain(registry: Registry, code: &str, output: ErrorOutputType) {
let normalised =
if code.starts_with('E') { code.to_string() } else { format!("E{0:0>4}", code) };
@@ -1290,7 +1309,7 @@ pub fn init_env_logger(env: &str) {
Ok(value) => match value.as_ref() {
"always" => true,
"never" => false,
- "auto" => stdout_isatty(),
+ "auto" => stderr_isatty(),
_ => early_error(
ErrorOutputType::default(),
&format!(
@@ -1299,7 +1318,7 @@ pub fn init_env_logger(env: &str) {
),
),
},
- Err(std::env::VarError::NotPresent) => stdout_isatty(),
+ Err(std::env::VarError::NotPresent) => stderr_isatty(),
Err(std::env::VarError::NotUnicode(_value)) => early_error(
ErrorOutputType::default(),
"non-Unicode log color value: expected one of always, never, or auto",