Add PB_MANY_FIELDS option for supporting fields > 255.

[apps/agl-service-can-low-level.git] / generator / nanopb_generator.py

diff --git a/generator/nanopb_generator.py b/generator/nanopb_generator.py
index 337b32a..405feda 100644 (file)
--- a/generator/nanopb_generator.py
+++ b/generator/nanopb_generator.py
@@ -1,7 +1,27 @@
 '''Generate header file for nanopb from a ProtoBuf FileDescriptorSet.'''
 
-import google.protobuf.descriptor_pb2 as descriptor
-import nanopb_pb2
+try:
+    import google.protobuf.descriptor_pb2 as descriptor
+except:
+    print
+    print "*************************************************************"
+    print "*** Could not import the Google protobuf Python libraries ***"
+    print "*** Try installing package 'python-protobuf' or similar.  ***"
+    print "*************************************************************"
+    print
+    raise
+
+try:
+    import nanopb_pb2
+except:
+    print
+    print "***************************************************************"
+    print "*** Could not import the precompiled nanopb_pb2.py.         ***"
+    print "*** Run 'make' in the 'generator' folder to update the file.***"
+    print "***************************************************************"
+    print
+    raise
+
 import os.path
 
 # Values are tuple (c type, pb ltype)
@@ -231,6 +251,20 @@ class Field:
             result += '\n    &%s_default}' % (self.struct_name + self.name)
         
         return result
+    
+    def needs_32bit_pb_field_t(self):
+        '''Determine if this field needs 32bit pb_field_t structure to compile properly.
+        Returns True, False or a C-expression for assert.'''
+        if self.tag > 255 or self.max_size > 255:
+            return True
+        
+        if self.ltype == 'PB_LTYPE_SUBMESSAGE':
+            if self.htype == 'PB_HTYPE_ARRAY':
+                return 'pb_membersize(%s, %s[0]) > 255' % (self.struct_name, self.name)
+            else:
+                return 'pb_membersize(%s, %s) > 255' % (self.struct_name, self.name)
+        
+        return False
 
 class Message:
     def __init__(self, names, desc):
@@ -323,7 +357,7 @@ def toposort2(data):
     '''
     for k, v in data.items():
         v.discard(k) # Ignore self dependencies
-    extra_items_in_deps = reduce(set.union, data.values()) - set(data.keys())
+    extra_items_in_deps = reduce(set.union, data.values(), set()) - set(data.keys())
     data.update(dict([(item, set()) for item in extra_items_in_deps]))
     while True:
         ordered = set(item for item,dep in data.items() if not dep)
@@ -347,7 +381,7 @@ def sort_dependencies(messages):
         if msgname in message_by_name:
             yield message_by_name[msgname]
 
-def generate_header(headername, enums, messages):
+def generate_header(dependencies, headername, enums, messages):
     '''Generate content for a header file.
     Generates strings, which should be concatenated and stored to file.
     '''
@@ -359,6 +393,11 @@ def generate_header(headername, enums, messages):
     yield '#define _PB_%s_\n' % symbol
     yield '#include <pb.h>\n\n'
     
+    for dependency in dependencies:
+        noext = os.path.splitext(dependency)[0]
+        yield '#include "%s.pb.h"\n' % noext
+    yield '\n'
+    
     yield '/* Enum definitions */\n'
     for enum in enums:
         yield str(enum) + '\n\n'
@@ -377,6 +416,40 @@ def generate_header(headername, enums, messages):
     for msg in messages:
         yield msg.fields_declaration() + '\n'
     
+    count_required_fields = lambda m: len([f for f in msg.fields if f.htype == 'PB_HTYPE_REQUIRED'])
+    largest_msg = max(messages, key = count_required_fields)
+    largest_count = count_required_fields(largest_msg)
+    if largest_count > 64:
+        yield '\n/* Check that missing required fields will be properly detected */\n'
+        yield '#if PB_MAX_REQUIRED_FIELDS < %d\n' % largest_count
+        yield '#warning Properly detecting missing required fields in %s requires \\\n' % largest_msg.name
+        yield '         setting PB_MAX_REQUIRED_FIELDS to %d or more.\n' % largest_count
+        yield '#endif\n'
+    
+    worst = False
+    worst_field = ''
+    for msg in messages:
+        for field in msg.fields:
+            status = field.needs_32bit_pb_field_t()
+            if status == True:
+                worst = True
+                worst_field = str(field.struct_name) + '.' + str(field.name)
+            elif status != False:
+                if worst == False:
+                    worst = status
+                elif worst != True:
+                    worst += ' || ' + status
+
+    if worst != False:
+        yield '\n/* Check that field information fits in pb_field_t */\n'
+        yield '#ifndef PB_MANY_FIELDS\n'
+        if worst == True:
+            yield '#error Field descriptor for %s is too large. Define PB_MANY_FIELDS to fix this.\n' % worst_field
+        else:
+            yield 'STATIC_ASSERT(!(%s), YOU_MUST_DEFINE_PB_MANY_FIELDS)\n' % worst
+        yield '#endif\n'
+    
+    # End of header
     yield '\n#endif\n'
 
 def generate_source(headername, enums, messages):
@@ -415,8 +488,13 @@ if __name__ == '__main__':
     
     print "Writing to " + headername + " and " + sourcename
     
+    # List of .proto files that should not be included in the C header file
+    # even if they are mentioned in the source .proto.
+    excludes = ['nanopb.proto', 'google/protobuf/descriptor.proto']
+    dependencies = [d for d in fdesc.file[0].dependency if d not in excludes]
+    
     header = open(headername, 'w')
-    for part in generate_header(headerbasename, enums, messages):
+    for part in generate_header(dependencies, headerbasename, enums, messages):
         header.write(part)
 
     source = open(sourcename, 'w')