API: Add support for type aliases

Previously all types are compound. This adds support for aliases,
so one can do things like:

typedef u32 interface_index;

or
typedef u8 ip4_address[4];

Change-Id: I0455cad0123fc88acb491d2a3ea2725426bdb246
Signed-off-by: Ole Troan <ot@cisco.com>
Signed-off-by: Klement Sekera <ksekera@cisco.com>

3 files changed, 40 insertions, 3 deletions

diff --git a/src/tools/vppapigen/vppapigen.py b/src/tools/vppapigen/vppapigen.py
index 9d04ec24cfc..3f882c455e6 100755
--- a/src/tools/vppapigen/vppapigen.py
+++ b/src/tools/vppapigen/vppapigen.py
@@ -151,6 +151,25 @@ class Typedef():
         return self.name + str(self.flags) + str(self.block)
 
 
+class Using():
+    def __init__(self, name, alias):
+        global global_crc
+        self.name = name
+
+        if isinstance(alias, Array):
+            a = { 'type': alias.fieldtype,
+                  'length': alias.length }
+        else:
+            a = { 'type': alias.fieldtype }
+        self.alias = a
+        self.crc = binascii.crc32(str(alias)) & 0xffffffff
+        global_crc = binascii.crc32(str(alias), global_crc)
+        global_type_add(name)
+
+    def __repr__(self):
+        return self.name + str(self.alias)
+
+
 class Union():
     def __init__(self, name, block):
         self.type = 'Union'
@@ -457,6 +476,10 @@ class VPPAPIParser(object):
         '''typedef : TYPEDEF ID '{' block_statements_opt '}' ';' '''
         p[0] = Typedef(p[2], [], p[4])
 
+    def p_typedef_alias(self, p):
+        '''typedef : TYPEDEF declaration '''
+        p[0] = Using(p[2].fieldname, p[2])
+
     def p_block_statements_opt(self, p):
         '''block_statements_opt : block_statements '''
         p[0] = p[1]
@@ -594,6 +617,7 @@ class VPPAPI(object):
         s['Service'] = []
         s['types'] = []
         s['Import'] = []
+        s['Alias'] = {}
         for o in objs:
             tname = o.__class__.__name__
             if isinstance(o, Define):
@@ -608,6 +632,8 @@ class VPPAPI(object):
                         s['Service'].append(o2)
             elif isinstance(o, Enum) or isinstance(o, Typedef) or isinstance(o, Union):
                 s['types'].append(o)
+            elif isinstance(o, Using):
+                s['Alias'][o.name] = o.alias
             else:
                 if tname not in s:
                     raise ValueError('Unknown class type: {} {}'.format(tname, o))
@@ -686,7 +712,8 @@ class VPPAPI(object):
             if in_import and not (isinstance(o, Enum) or
                                   isinstance(o, Union) or
                                   isinstance(o, Typedef) or
-                                  isinstance(o, Import)):
+                                  isinstance(o, Import) or
+                                  isinstance(o, Using)):
                 continue
             if isinstance(o, Import):
                 self.process_imports(o.result, True, result)
diff --git a/src/tools/vppapigen/vppapigen_c.py b/src/tools/vppapigen/vppapigen_c.py
index b56e0722122..2a66ff3159e 100644
--- a/src/tools/vppapigen/vppapigen_c.py
+++ b/src/tools/vppapigen/vppapigen_c.py
@@ -94,7 +94,7 @@ def duplicate_wrapper_tail():
     return '#endif\n\n'
 
 
-def typedefs(objs, filename):
+def typedefs(objs, aliases, filename):
     name = filename.replace('.', '_')
     output = '''\
 
@@ -106,6 +106,15 @@ def typedefs(objs, filename):
 #define included_{module}
 '''
     output = output.format(module=name)
+
+    for k, v in aliases.items():
+        output += duplicate_wrapper_head(k)
+        if 'length' in v:
+            output +=  'typedef %s vl_api_%s_t[%s];\n' % (v['type'], k, v['length'])
+        else:
+            output += 'typedef %s vl_api_%s_t;\n' % (v['type'], k)
+        output += duplicate_wrapper_tail()
+
     for o in objs:
         tname = o.__class__.__name__
         output += duplicate_wrapper_head(o.name)
@@ -276,7 +285,7 @@ def run(input_filename, s, file_crc):
     output += msg_ids(s)
     output += msg_names(s)
     output += msg_name_crc_list(s, filename)
-    output += typedefs(s['types'] + s['Define'], filename + file_extension)
+    output += typedefs(s['types'] + s['Define'], s['Alias'], filename + file_extension)
     output += printfun(s['types'] + s['Define'])
     output += endianfun(s['types'] + s['Define'])
     output += version_tuple(s, basename)
diff --git a/src/tools/vppapigen/vppapigen_json.py b/src/tools/vppapigen/vppapigen_json.py
index 2991bec57ac..b57e16c990d 100644
--- a/src/tools/vppapigen/vppapigen_json.py
+++ b/src/tools/vppapigen/vppapigen_json.py
@@ -65,5 +65,6 @@ def run(filename, s, file_crc):
     j['unions'] = walk_defs([o for o in s['types'] if o.__class__.__name__ == 'Union'])
     j['enums'] = walk_enums([o for o in s['types'] if o.__class__.__name__ == 'Enum'])
     j['services'] = walk_services(s['Service'])
+    j['aliases'] = s['Alias']
     j['vl_api_version'] = hex(file_crc)
     return json.dumps(j, indent=4, separators=(',', ': '))