Use WITH_MADVISE and WITH_FALLOCATE pp defines to bypass.

Author: evoskuil

src/memory/map.cpp

@@ -562,7 +562,11 @@ bool map::resize_(size_t size) NOEXCEPT
     // TODO: implement fallocate for macOS (open and write a byte per block).
     if (::ftruncate(opened_, size) == fail)
 #else
+    #if defined (WITH_FALLOCATE)
     if (::fallocate(opened_, 0, capacity_, size - capacity_) == fail)
+    #else
+    if (::ftruncate(opened_, size) == fail)
+    #endif
 #endif
     {
         // Disk full is the only restartable store failure (leave mapped).
@@ -594,6 +598,7 @@ bool map::finalize_(size_t size) NOEXCEPT
         return false;
     }
 
+#if defined (WITH_MADVISE)
 #if !defined(HAVE_MSC)
     // Get page size (usually 4KB).
     const int page_size = ::sysconf(_SC_PAGESIZE);
@@ -629,6 +634,7 @@ bool map::finalize_(size_t size) NOEXCEPT
         }
     }
 #endif
+#endif // WITH_MADVISE
 
     loaded_ = true;
     capacity_ = size;