rt: Add RUST_DEBUG_MEM to rust_env to avoid races

src/libcore/cleanup.rs

@@ -145,11 +145,7 @@ unsafe fn each_live_alloc(f: &fn(box: *mut BoxRepr, uniq: bool) -> bool) {
 
 #[cfg(unix)]
 fn debug_mem() -> bool {
-    use os;
+    ::rt::env::get().debug_mem
-    use libc;
-    do os::as_c_charp("RUST_DEBUG_MEM") |p| {
-        unsafe { libc::getenv(p) != null() }
-    }
 }
 
 #[cfg(windows)]

src/libcore/rt/env.rs

@@ -0,0 +1,47 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! Runtime environment settings
+
+use libc::{size_t, c_char, c_int};
+
+pub struct Environment {
+    /// The number of threads to use by default
+    num_sched_threads: size_t,
+    /// The minimum size of a stack segment
+    min_stack_size: size_t,
+    /// The maximum amount of total stack per task before aborting
+    max_stack_size: size_t,
+    /// The default logging configuration
+    logspec: *c_char,
+    /// Record and report detailed information about memory leaks
+    detailed_leaks: bool,
+    /// Seed the random number generator
+    rust_seed: *c_char,
+    /// Poison allocations on free
+    poison_on_free: bool,
+    /// The argc value passed to main
+    argc: c_int,
+    /// The argv value passed to main
+    argv: **c_char,
+    /// Print GC debugging info
+    debug_mem: bool
+}
+
+/// Get the global environment settings
+/// # Safety Note
+/// This will abort the process if run outside of task context
+pub fn get() -> &Environment {
+    unsafe { rust_get_rt_env() }
+}
+
+extern {
+    fn rust_get_rt_env() -> &Environment;
+}

src/libcore/rt/mod.rs

@@ -45,3 +45,4 @@ mod work_queue;
 mod stack;
 mod context;
 mod thread;
+pub mod env;

src/rt/rust_builtin.cpp

@@ -876,6 +876,11 @@ rust_dbg_extern_identity_u8(char u) {
     return u;
 }
 
+extern "C" rust_env*
+rust_get_rt_env() {
+    rust_task *task = rust_get_current_task();
+    return task->kernel->env;
+}
 
 //
 // Local Variables:

src/rt/rust_env.cpp

@@ -23,6 +23,7 @@
 #define DETAILED_LEAKS "DETAILED_LEAKS"
 #define RUST_SEED "RUST_SEED"
 #define RUST_POISON_ON_FREE "RUST_POISON_ON_FREE"
+#define RUST_DEBUG_MEM "RUST_DEBUG_MEM"
 
 #if defined(__WIN32__)
 static int
@@ -128,6 +129,7 @@ load_env(int argc, char **argv) {
     env->poison_on_free = getenv(RUST_POISON_ON_FREE) != NULL;
     env->argc = argc;
     env->argv = argv;
+    env->debug_mem = getenv(RUST_DEBUG_MEM) != NULL;
     return env;
 }
 

src/rt/rust_env.h

@@ -14,16 +14,20 @@
 
 #include "rust_globals.h"
 
+// Avoiding 'bool' type here since I'm not sure it has a standard size
+typedef uint8_t rust_bool;
+
 struct rust_env {
     size_t num_sched_threads;
     size_t min_stack_size;
     size_t max_stack_size;
     char* logspec;
-    bool detailed_leaks;
+    rust_bool detailed_leaks;
     char* rust_seed;
-    bool poison_on_free;
+    rust_bool poison_on_free;
     int argc;
     char **argv;
+    rust_bool debug_mem;
 };
 
 rust_env* load_env(int argc, char **argv);

src/rt/rustrt.def.in

@@ -201,3 +201,4 @@ rust_dbg_extern_identity_u64
 rust_dbg_extern_identity_TwoU64s
 rust_dbg_extern_identity_double
 rust_dbg_extern_identity_u8
+rust_get_rt_env