Give base::SharedMemory::CreateAnonymous an executable flag

NaCl on Mac and Linux needs to create a shared memory object that it can
later make executable with mprotect.  Express this need in the interface it
uses.  Add a test that pages mapped from such an object can later be passed
to mprotect with PROT_EXEC.

This lays the groundwork for a later change that will sometimes use a
different method to allocate an object on Linux when it needs to be
executable.  On some Linux distributions, shm_open yields objects whose
mappings cannot be made executable.

BUG= http://code.google.com/p/chromium/issues/detail?id=103377
TEST= SharedMemory.AnonymousExecutable

R=mark@chromium.org,jam@chromium.org,amit@chromium.org,ben@chromium.org

Review URL: http://codereview.chromium.org/8585002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@112570 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 4 insertions, 3 deletions

diff --git a/base/shared_memory_android.cc b/base/shared_memory_android.cc
index 72c3a56..8e55e3a 100644
--- a/base/shared_memory_android.cc
+++ b/base/shared_memory_android.cc
@@ -16,12 +16,13 @@ namespace base {
 // all the file descriptors from different processes associated with the region
 // are closed, the memory buffer will go away.
 
-bool SharedMemory::CreateNamed(const std::string& name,
-                               bool open_existing, uint32 size) {
+bool SharedMemory::Create(const SharedMemoryCreateOptions& options) {
   DCHECK_EQ(-1, mapped_file_ );
 
   // "name" is just a label in ashmem. It is visible in /proc/pid/maps.
-  mapped_file_ = ashmem_create_region(name.c_str(), size);
+  mapped_file_ = ashmem_create_region(
+      options.name == NULL ? "" : options.name.c_str(),
+      options.size);
   if (-1 == mapped_file_) {
     DLOG(ERROR) << "Shared memory creation failed";
     return false;