auto merge of #8645 : alexcrichton/rust/issue-6436-run-non-blocking, r=brson

This overhauls `std::run` to instead run on top of libuv. This is *not* in a mergeable state, I've been attempting to diagnose failures in the compiletest suite. I've managed to find a fair number of bugs so far, but I still  don't seem to be done yet.

Notable changes:
* This requires upgrading libuv. From the discussion on #6567, I took libuv master from a few days ago, applied one patch to fix process spawning with multiple event loops in libuv, and pushed to my own fork
* The build system for libuv has changed since we last used it. There's some extra checkout from a google build system which apparently does all the magic if you don't want to require autotools, and the google system just requires python. I updated the Makefile to get this build system and build libuv with it instead. This is untested on windows and arm, and both will probably need to see some improvement.
* This required adding some pipe bindings to libuv as well. Currently the support is pretty simple and probably completely unsafe for pipes, but you at least get read/write methods. This is necessary for capturing output of processes.
* I didn't redesign `std::run` at all, I simply tried to reimplement all the existing functionality on top of libuv. Some functions ended up dying, but nothing major. All uses of `std::run` in the compiler still work just fine.

I'm not quite sure how the rest of the runtime deals with this, but I marked process structures as `no_send` because the waiting/waking up has to happen in the same event loop right now. If processes start migrating between event loops then very bad things can happen. This may be what threadsafe I/O would fix, and I would be more than willing to rebase on that if it lands first.

Anyway, for now I wanted to put this up for review, I'm still investigating the corruption/deadlock bugs, but this is in an *almost* workable state. Once I find the bugs I'll also rebase on the current master.

2 files changed, 9 insertions, 7 deletions

diff --git a/src/librustpkg/source_control.rs b/src/librustpkg/source_control.rs
index caa004a53b2..c67a8158139 100644
--- a/src/librustpkg/source_control.rs
+++ b/src/librustpkg/source_control.rs
@@ -89,7 +89,7 @@ pub fn git_clone_general(source: &str, target: &Path, v: &Version) -> bool {
 
 fn process_output_in_cwd(prog: &str, args: &[~str], cwd: &Path) -> ProcessOutput {
     let mut prog = Process::new(prog, args, ProcessOptions{ dir: Some(cwd)
-                                ,..ProcessOptions::new()});
+                                ,..ProcessOptions::new()}).unwrap();
     prog.finish_with_output()
 }
 
diff --git a/src/librustpkg/tests.rs b/src/librustpkg/tests.rs
index 98999da41c8..b0d996ea0af 100644
--- a/src/librustpkg/tests.rs
+++ b/src/librustpkg/tests.rs
@@ -112,13 +112,14 @@ fn mk_temp_workspace(short_name: &Path, version: &Version) -> Path {
 
 fn run_git(args: &[~str], env: Option<~[(~str, ~str)]>, cwd: &Path, err_msg: &str) {
     let cwd = (*cwd).clone();
-    let mut prog = run::Process::new("git", args, run::ProcessOptions {
+    let prog = run::Process::new("git", args, run::ProcessOptions {
         env: env,
         dir: Some(&cwd),
         in_fd: None,
         out_fd: None,
         err_fd: None
     });
+    let mut prog = prog.unwrap();
     let rslt = prog.finish_with_output();
     if rslt.status != 0 {
         fail!("%s [git returned %?, output = %s, error = %s]", err_msg,
@@ -226,7 +227,7 @@ fn command_line_test_with_env(args: &[~str], cwd: &Path, env: Option<~[(~str, ~s
         in_fd: None,
         out_fd: None,
         err_fd: None
-    });
+    }).unwrap();
     let output = prog.finish_with_output();
     debug!("Output from command %s with args %? was %s {%s}[%?]",
                     cmd, args, str::from_bytes(output.output),
@@ -1027,16 +1028,17 @@ fn test_extern_mod() {
                      test_sysroot().to_str(),
                      exec_file.to_str());
 
-    let mut prog = run::Process::new(rustc.to_str(), [main_file.to_str(),
-                                                      ~"--sysroot", test_sysroot().to_str(),
-                                               ~"-o", exec_file.to_str()],
-                                     run::ProcessOptions {
+    let prog = run::Process::new(rustc.to_str(), [main_file.to_str(),
+                                                  ~"--sysroot", test_sysroot().to_str(),
+                                                  ~"-o", exec_file.to_str()],
+                                 run::ProcessOptions {
         env: env,
         dir: Some(&dir),
         in_fd: None,
         out_fd: None,
         err_fd: None
     });
+    let mut prog = prog.unwrap();
     let outp = prog.finish_with_output();
     if outp.status != 0 {
         fail!("output was %s, error was %s",