Modify the NaCl_page_alloc_hint function to use VirtualQuery to check

src/trusted/service_runtime/arch/x86_32/sel_addrspace_x86_32.c

Index: src/trusted/service_runtime/arch/x86_32/sel_addrspace_x86_32.c
===================================================================
--- src/trusted/service_runtime/arch/x86_32/sel_addrspace_x86_32.c	(revision 6420)
+++ src/trusted/service_runtime/arch/x86_32/sel_addrspace_x86_32.c	(working copy)
@@ -9,7 +9,6 @@
 #include "native_client/src/trusted/service_runtime/sel_memory.h"
 #include "native_client/src/trusted/service_runtime/sel_ldr.h"
 
-
 NaClErrorCode NaClAllocateSpace(void **mem, size_t addrsp_size) {
   int result;
 
@@ -26,6 +25,18 @@
   *mem = (void *) NACL_TRAMPOLINE_START;
   result = NaCl_page_alloc_at_addr(mem, addrsp_size);
   *mem = 0;
+#elif NACL_WINDOWS && NACL_BUILD_SUBARCH == 32
+  /*
+   * On 32 bit Windows XP, a 1Gb region of address space is reserved before

[Mark Seaborn, 2011/08/16 20:18:43]

Just say "32-bit Windows".  It's not just XP.

+   * starting up this process to make sure we can get a contiguous block. Look
+   * for it and if found, pass the address to NaCl_page_alloc_at_addr so it can
+   * use this pre-reserved block.
+   */
+  if (0 == NaCl_find_prereserved_sandbox_memory(mem, addrsp_size)) {
+    result = NaCl_page_alloc_at_addr(mem, addrsp_size);
+  } else {
+    result = NaCl_page_alloc(mem, addrsp_size);
+  }
 #else
   result = NaCl_page_alloc(mem, addrsp_size);
 #endif