From 900b1f60596c93f7cf02817e51da669555f391f2 Mon Sep 17 00:00:00 2001
From: Jim Blandy <jimb@mozilla.com>
Date: Tue, 14 Jun 2011 19:21:47 -0700
Subject: [PATCH] Bug 661567: Implement RuntimeAllocPolicy, providing proper
 memory accounting in GC'd objects that live longer than a JSContext. r=luke

---
 js/src/jscntxt.h | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/js/src/jscntxt.h b/js/src/jscntxt.h
index 8067aedf2ad..285fc0430dd 100644
--- a/js/src/jscntxt.h
+++ b/js/src/jscntxt.h
@@ -1430,6 +1430,28 @@ struct JSContext
 
 namespace js {
 
+/*
+ * Allocation policy that uses JSRuntime::malloc_ and friends, so that
+ * memory pressure is properly accounted for. This is suitable for
+ * long-lived objects owned by the JSRuntime.
+ *
+ * Since it doesn't hold a JSContext (those may not live long enough), it
+ * can't report out-of-memory conditions itself; the caller must check for
+ * OOM and take the appropriate action.
+ */
+class RuntimeAllocPolicy
+{
+    JSRuntime *const runtime;
+
+  public:
+    RuntimeAllocPolicy(JSRuntime *rt) : runtime(rt) {}
+    RuntimeAllocPolicy(JSContext *cx) : runtime(cx->runtime) {}
+    void *malloc_(size_t bytes) { return runtime->malloc_(bytes); }
+    void *realloc_(void *p, size_t bytes) { return runtime->realloc_(p, bytes); }
+    void free_(void *p) { runtime->free_(p); }
+    void reportAllocOverflow() const {}
+};
+
 #ifdef JS_THREADSAFE
 # define JS_THREAD_ID(cx)       ((cx)->thread() ? (cx)->thread()->id : 0)
 #endif