Add UMA for testing whether device supports memory mapping APK files with executable permissions.

third_party/android_crazy_linker/src/src/crazy_linker_api.cpp

Index: third_party/android_crazy_linker/src/src/crazy_linker_api.cpp
diff --git a/third_party/android_crazy_linker/src/src/crazy_linker_api.cpp b/third_party/android_crazy_linker/src/src/crazy_linker_api.cpp
index 10a64bfa63ee9b6290ba88a64ec33340d48073e4..162f00cf220bcb420a18cd7fee036d6540d4905f 100644
--- a/third_party/android_crazy_linker/src/src/crazy_linker_api.cpp
+++ b/third_party/android_crazy_linker/src/src/crazy_linker_api.cpp
@@ -6,6 +6,7 @@
 
 #include <crazy_linker.h>
 
+#include <limits.h>
 #include <string.h>
 
 #include "crazy_linker_error.h"
@@ -24,6 +25,7 @@ using crazy::Error;
 using crazy::SearchPathList;
 using crazy::ScopedGlobalLock;
 using crazy::LibraryView;
+using crazy::FileDescriptor;
 
 //
 // crazy_context_t
@@ -387,4 +389,20 @@ void crazy_library_close_with_context(crazy_library_t* library,
   }
 }
 
+crazy_status_t crazy_linker_test_load_from_apk(const char* apkfile_name) {
+  FileDescriptor fd(apkfile_name);
+
+  LOG("%s: Memory mapping the first page of %s\n", __FUNCTION__, apkfile_name);
+  void* address = fd.Map(NULL, PAGE_SIZE, PROT_EXEC, MAP_PRIVATE, 0);
+
+  crazy_status_t status = CRAZY_STATUS_FAILURE;
+  if (address != MAP_FAILED) {
+    status = CRAZY_STATUS_SUCCESS;
+    munmap(address, PAGE_SIZE);
+  }

[picksi1, 2014/10/10 10:52:18]

I think this would be clearer is we swapped the if/else round and remove the
default status assignment, e.g.

crazy_status_t status;
if (address == MAP_FAILED) {
   status = CRAZY_STATUS_FAILURE
}
else {
   status = CRAZY_STATUS_SUCCESS;
   munmap(address, PAGE_SIZE);
}

[petrcermak, 2014/10/10 14:20:14]

Done.

+
+  LOG("  %s\n", status == CRAZY_STATUS_SUCCESS ? "supported" : "NOT supported");
+  return status;
+}
+
 }  // extern "C"