Add new option max_length for strings (issue #107)

Max_size is the allocated size, so users had to add +1 for
the null terminator. Max_length does the +1 automatically
in the generator.

1 files changed, 4 insertions, 0 deletions

diff --git a/generator/nanopb_generator.py b/generator/nanopb_generator.py
index 6e5ebaf9..ca60c03a 100755
--- a/generator/nanopb_generator.py
+++ b/generator/nanopb_generator.py
@@ -270,6 +270,10 @@ class Field:
         # Parse field options
         if field_options.HasField("max_size"):
             self.max_size = field_options.max_size
+        
+        if desc.type == FieldD.TYPE_STRING and field_options.HasField("max_length"):
+            # max_length overrides max_size for strings
+            self.max_size = field_options.max_length + 1
 
         if field_options.HasField("max_count"):
             self.max_count = field_options.max_count