Merge #251 #271

251: Support mounting on SELinux r=reitermarkus a=cyplo

This should allow `cross` to work on both non-SELinux enabled systems
and SELinux ones.

I've tested on Fedora 29 for SELinux system.

Fixes #112 that was originally reported from Fedora as well I believe.

271: Minor improvements to wording r=reitermarkus a=spl

* Fix a typo in "QEMU bug sand"
* Add a link for QEMU
* Clarify and simplify various other things about the wording

The diff looks worse than the changes are. I tried to keep to the 80-column width since it looked like the rest of the text was that way. GitHub's “rich diff” seems to help here.

Co-authored-by: Cyryl Płotnicki <cyplo@cyplo.net>
Co-authored-by: Sean Leather <sean.leather@gmail.com>

README.md

@@ -177,17 +177,18 @@ that only support `xargo`.
 A target is considered as "supported" if `cross` can cross compile a
 "non-trivial" (binary) crate, usually Cargo, for that target.
 
-Testing support is more complicated. It relies on QEMU user emulation, so
-testing may sometimes fail due to QEMU bug sand not because there's a bug in the
-crate. That being said, `cross test` is assumed to "work" (`test` column in the
-table below) if it can successfully
-run [compiler-builtins](https://github.com/rust-lang-nursery/compiler-builtins)
-test suite.
-
-Also, testing is very slow. `cross` will actually run units tests *sequentially*
-because QEMU gets upset when you spawn several threads. This also means that, if
-one of your unit tests spawns several threads then it's more likely to fail or,
-worst, "hang" (never terminate).
+Testing support (`cross test`) is more complicated. It relies on [QEMU]
+emulation, so testing may fail due to QEMU bugs rather than bugs in your crate.
+That said, a target has a ✓ in `test` column of the table below if it can run
+the [`compiler-builtins`] test suite.
+
+[QEMU]: https://www.qemu.org/
+[`compiler-builtins`]: https://github.com/rust-lang-nursery/compiler-builtins
+
+Also, testing is very slow. `cross test` runs units tests *sequentially* because
+QEMU gets upset when you spawn multiple threads. This means that, if one of your
+unit tests spawns threads, then it's more likely to fail or, worst, never
+terminate.
 
 | Target                               |  libc  |   GCC   | OpenSSL | C++ | QEMU  | `test` |
 |--------------------------------------|--------|---------|---------|:---:|-------|:------:|

src/docker.rs

@@ -153,12 +153,12 @@ pub fn run(target: &Target,
 
     docker
         .args(&["-e", &format!("CROSS_RUNNER={}", runner.unwrap_or_else(|| String::new()))])
-        .args(&["-v", &format!("{}:/xargo", xargo_dir.display())])
-        .args(&["-v", &format!("{}:/cargo", cargo_dir.display())])
+        .args(&["-v", &format!("{}:/xargo:Z", xargo_dir.display())])
+        .args(&["-v", &format!("{}:/cargo:Z", cargo_dir.display())])
         .args(&["-v", "/cargo/bin"]) // Prevent `bin` from being mounted inside the Docker container.
-        .args(&["-v", &format!("{}:/project:ro", root.display())])
-        .args(&["-v", &format!("{}:/rust:ro", sysroot.display())])
-        .args(&["-v", &format!("{}:/target", target_dir.display())])
+        .args(&["-v", &format!("{}:/project:Z,ro", root.display())])
+        .args(&["-v", &format!("{}:/rust:Z,ro", sysroot.display())])
+        .args(&["-v", &format!("{}:/target:Z", target_dir.display())])
         .args(&["-w", "/project"])
         .args(&["-it", &image(toml, target)?])
         .args(&["sh", "-c", &format!("PATH=$PATH:/rust/bin {:?}", cmd)])