diff options
Diffstat (limited to 'vendor/backtrace/tests/current-exe-mismatch.rs')
-rw-r--r-- | vendor/backtrace/tests/current-exe-mismatch.rs | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/vendor/backtrace/tests/current-exe-mismatch.rs b/vendor/backtrace/tests/current-exe-mismatch.rs new file mode 100644 index 0000000..b655827 --- /dev/null +++ b/vendor/backtrace/tests/current-exe-mismatch.rs @@ -0,0 +1,134 @@ +// rust-lang/rust#101913: when you run your program explicitly via `ld.so`, +// `std::env::current_exe` will return the path of *that* program, and not +// the Rust program itself. + +use std::io::{BufRead, BufReader}; +use std::path::{Path, PathBuf}; +use std::process::Command; + +mod common; + +fn main() { + if std::env::var(VAR).is_err() { + // the parent waits for the child; then we then handle either printing + // "test result: ok", "test result: ignored", or panicking. + match parent() { + Ok(()) => { + println!("test result: ok"); + } + Err(EarlyExit::IgnoreTest(_)) => { + println!("test result: ignored"); + } + Err(EarlyExit::IoError(e)) => { + println!("{} parent encoutered IoError: {:?}", file!(), e); + panic!(); + } + } + } else { + // println!("{} running child", file!()); + child().unwrap(); + } +} + +const VAR: &str = "__THE_TEST_YOU_ARE_LUKE"; + +#[derive(Debug)] +enum EarlyExit { + IgnoreTest(String), + IoError(std::io::Error), +} + +impl From<std::io::Error> for EarlyExit { + fn from(e: std::io::Error) -> Self { + EarlyExit::IoError(e) + } +} + +fn parent() -> Result<(), EarlyExit> { + // If we cannot re-exec this test, there's no point in trying to do it. + if common::cannot_reexec_the_test() { + return Err(EarlyExit::IgnoreTest("(cannot reexec)".into())); + } + + let me = std::env::current_exe().unwrap(); + let ld_so = find_interpreter(&me)?; + + // use interp to invoke current exe, yielding child test. + // + // (if you're curious what you might compare this against, you can try + // swapping in the below definition for `result`, which is the easy case of + // not using the ld.so interpreter directly that Rust handled fine even + // prior to resolution of rust-lang/rust#101913.) + // + // let result = Command::new(me).env(VAR, "1").output()?; + let result = Command::new(ld_so).env(VAR, "1").arg(&me).output().unwrap(); + + if result.status.success() { + return Ok(()); + } + println!("stdout:\n{}", String::from_utf8_lossy(&result.stdout)); + println!("stderr:\n{}", String::from_utf8_lossy(&result.stderr)); + println!("code: {}", result.status); + panic!(); +} + +fn child() -> Result<(), EarlyExit> { + let bt = backtrace::Backtrace::new(); + println!("{:?}", bt); + + let mut found_my_name = false; + + let my_filename = file!(); + 'frames: for frame in bt.frames() { + let symbols = frame.symbols(); + if symbols.is_empty() { + continue; + } + + for sym in symbols { + if let Some(filename) = sym.filename() { + if filename.ends_with(my_filename) { + // huzzah! + found_my_name = true; + break 'frames; + } + } + } + } + + assert!(found_my_name); + + Ok(()) +} + +// we use the `readelf` command to extract the path to the interpreter requested +// by our binary. +// +// if we cannot `readelf` for some reason, or if we fail to parse its output, +// then we will just give up on this test (and not treat it as a test failure). +fn find_interpreter(me: &Path) -> Result<PathBuf, EarlyExit> { + let result = Command::new("readelf") + .arg("-l") + .arg(me) + .output() + .map_err(|_err| EarlyExit::IgnoreTest("readelf invocation failed".into()))?; + if result.status.success() { + let r = BufReader::new(&result.stdout[..]); + for line in r.lines() { + let line = line?; + let line = line.trim(); + let prefix = "[Requesting program interpreter: "; + if let Some((_, suffix)) = line.split_once(prefix) { + if let Some((found_path, _)) = suffix.rsplit_once("]") { + return Ok(found_path.into()); + } + } + } + + Err(EarlyExit::IgnoreTest( + "could not find interpreter from readelf output".into(), + )) + } else { + Err(EarlyExit::IgnoreTest("readelf returned non-success".into())) + } +} |