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.

1 files changed, 36 insertions, 9 deletions

diff --git a/src/rt/rust_uv.cpp b/src/rt/rust_uv.cpp
index 8ef4572f810..a181e76df5c 100644
--- a/src/rt/rust_uv.cpp
+++ b/src/rt/rust_uv.cpp
@@ -329,20 +329,13 @@ rust_uv_get_len_from_buf(uv_buf_t buf) {
     return buf.len;
 }
 
-extern "C" uv_err_t
-rust_uv_last_error(uv_loop_t* loop) {
-    return uv_last_error(loop);
-}
-
 extern "C" const char*
-rust_uv_strerror(uv_err_t* err_ptr) {
-    uv_err_t err = *err_ptr;
+rust_uv_strerror(int err) {
     return uv_strerror(err);
 }
 
 extern "C" const char*
-rust_uv_err_name(uv_err_t* err_ptr) {
-    uv_err_t err = *err_ptr;
+rust_uv_err_name(int err) {
     return uv_err_name(err);
 }
 
@@ -553,3 +546,37 @@ extern "C" uv_loop_t*
 rust_uv_get_loop_from_fs_req(uv_fs_t* req) {
   return req->loop;
 }
+extern "C" int
+rust_uv_spawn(uv_loop_t *loop, uv_process_t *p, uv_process_options_t options) {
+  return uv_spawn(loop, p, options);
+}
+
+extern "C" int
+rust_uv_process_kill(uv_process_t *p, int signum) {
+  return uv_process_kill(p, signum);
+}
+
+extern "C" void
+rust_set_stdio_container_flags(uv_stdio_container_t *c, int flags) {
+  c->flags = (uv_stdio_flags) flags;
+}
+
+extern "C" void
+rust_set_stdio_container_fd(uv_stdio_container_t *c, int fd) {
+  c->data.fd = fd;
+}
+
+extern "C" void
+rust_set_stdio_container_stream(uv_stdio_container_t *c, uv_stream_t *stream) {
+  c->data.stream = stream;
+}
+
+extern "C" int
+rust_uv_process_pid(uv_process_t* p) {
+  return p->pid;
+}
+
+extern "C" int
+rust_uv_pipe_init(uv_loop_t *loop, uv_pipe_t* p, int ipc) {
+  return uv_pipe_init(loop, p, ipc);
+}