Add some type safety to other pagemap accesses.

Introduce a descriptor for the pagemap config and check that the source descriptor is compatible with the destination type.
2019-04-09 14:59:09 +01:00
parent 51fbdf3a44
commit a93f43fd2f
5 changed files with 79 additions and 2 deletions
--- a/src/override/malloc.cc
+++ b/src/override/malloc.cc
@@ -206,8 +206,16 @@ extern "C"
  }

 #ifdef SNMALLOC_EXPOSE_PAGEMAP
-  SNMALLOC_EXPORT void* SNMALLOC_NAME_MANGLE(snmalloc_get_global_pagemap)(void)
+  SNMALLOC_EXPORT void* SNMALLOC_NAME_MANGLE(snmalloc_get_global_pagemap)(
+    PagemapConfig const** config)
  {
+    if (config)
+    {
+      *config = &decltype(snmalloc::global_pagemap)::config;
+      assert(
+        decltype(snmalloc::global_pagemap)::cast_to_pagemap(
+          &snmalloc::global_pagemap, *config) == &snmalloc::global_pagemap);
+    }
    return &snmalloc::global_pagemap;
  }
 #endif