Merge branch 'json-view/16-view-simd' into json-view/19-edit-set

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

include/nlohmann/detail/view/document_data.hpp

@@ -13,9 +13,10 @@
 #include <cstdint> // uint32_t
 #include <cstring> // memcpy
 #include <functional> // less
+#include <limits> // numeric_limits
 #include <map> // map
 #include <memory> // unique_ptr
-#include <new> // operator new, placement new
+#include <new> // bad_alloc, operator new, placement new
 #include <string> // string
 #include <vector> // vector
 
@@ -121,13 +122,30 @@ struct document_data
         tape_cap = inline_cap;
     }
 
-    /// make room for n nodes; keeps the first tape_size nodes
+    /// the largest node count whose size in bytes fits a std::size_t
+    static constexpr std::size_t max_nodes() noexcept
+    {
+        return (std::numeric_limits<std::size_t>::max)() / sizeof(node);
+    }
+
+    [[noreturn]] NLOHMANN_VIEW_NOINLINE static void throw_bad_alloc()
+    {
+        NLOHMANN_VIEW_THROW(std::bad_alloc());
+    }
+
+    /// make room for n nodes; keeps the first tape_size nodes (throws
+    /// std::bad_alloc for a count that does not fit the address space,
+    /// instead of wrapping around in n * sizeof(node))
     void reserve(std::size_t n)
     {
         if (n <= tape_cap)
         {
             return;
         }
+        if (NLOHMANN_VIEW_UNLIKELY(n > max_nodes()))
+        {
+            throw_bad_alloc();
+        }
         node* fresh = static_cast<node*>(::operator new (n * sizeof(node)));
         if (tape_size != 0)
         {