generate proper API structs for GDNative extension extensions

The GDNative C API gets passed to libraries in a struct of function
pointers. To provide stable binary compatibility, each extension not
part of the core API is separated into its own sub-struct.

These structs aren't meant to be changed in order to keep binary
compatibility.

In case of an API extension, the structs include a `next` pointer
which can point to a new struct with additional function pointers.

Godot's build system generates the API structs automatically at
build time, but so far there has no support for the mentioned `next`
pointers.

This commit changes the API struct generation in such a way that code
that used previous headers will compile without problem with the new
headers.

The new extension-extensions (weird name, but that's what it is) get
generated recursively and include the version in the struct-name.
This commit is contained in:
karroffel 2018-02-09 11:44:54 +01:00
parent cbdd410a6f
commit 2fb66df669
1 changed files with 43 additions and 15 deletions

View File

@ -66,19 +66,30 @@ def _build_gdnative_api_struct_header(api):
out += ['};', '']
for name in api['extensions']:
out += [
'typedef struct godot_gdnative_ext_' + name + '_api_struct {',
def generate_extension_struct(name, ext, include_version=True):
ret_val = []
if ext['next']:
ret_val += generate_extension_struct(name, ext['next'])
ret_val += [
'typedef struct godot_gdnative_ext_' + name + ('' if not include_version else ('_{0}_{1}'.format(ext['version']['major'], ext['version']['minor']))) + '_api_struct {',
'\tunsigned int type;',
'\tgodot_gdnative_api_version version;',
'\tconst godot_gdnative_api_struct *next;'
]
for funcdef in api['extensions'][name]['api']:
for funcdef in ext['api']:
args = ', '.join(['%s%s' % (_spaced(t), n) for t, n in funcdef['arguments']])
out.append('\t%s(*%s)(%s);' % (_spaced(funcdef['return_type']), funcdef['name'], args))
ret_val.append('\t%s(*%s)(%s);' % (_spaced(funcdef['return_type']), funcdef['name'], args))
out += ['} godot_gdnative_ext_' + name + '_api_struct;', '']
ret_val += ['} godot_gdnative_ext_' + name + ('' if not include_version else ('_{0}_{1}'.format(ext['version']['major'], ext['version']['minor']))) + '_api_struct;', '']
return ret_val
for name in api['extensions']:
out += generate_extension_struct(name, api['extensions'][name], False)
out += [
'typedef struct godot_gdnative_core_api_struct {',
@ -113,18 +124,35 @@ def _build_gdnative_api_struct_source(api):
''
]
for name in api['extensions']:
out += [
'extern const godot_gdnative_ext_' + name + '_api_struct api_extension_' + name + '_struct = {',
'\tGDNATIVE_EXT_' + api['extensions'][name]['type'] + ',',
'\t{' + str(api['extensions'][name]['version']['major']) + ', ' + str(api['extensions'][name]['version']['minor']) + '},',
'\tNULL,'
def get_extension_struct_name(name, ext, include_version=True):
return 'godot_gdnative_ext_' + name + ('' if not include_version else ('_{0}_{1}'.format(ext['version']['major'], ext['version']['minor']))) + '_api_struct'
def get_extension_struct_instance_name(name, ext, include_version=True):
return 'api_extension_' + name + ('' if not include_version else ('_{0}_{1}'.format(ext['version']['major'], ext['version']['minor']))) + '_struct'
def get_extension_struct_definition(name, ext, include_version=True):
ret_val = []
if ext['next']:
ret_val += get_extension_struct_definition(name, ext['next'])
ret_val += [
'extern const ' + get_extension_struct_name(name, ext, include_version) + ' ' + get_extension_struct_instance_name(name, ext, include_version) + ' = {',
'\tGDNATIVE_EXT_' + ext['type'] + ',',
'\t{' + str(ext['version']['major']) + ', ' + str(ext['version']['minor']) + '},',
'\t' + ('NULL' if not ext['next'] else ('(const godot_gdnative_api_struct *)&' + get_extension_struct_instance_name(name, ext['next']))) + ','
]
for funcdef in api['extensions'][name]['api']:
out.append('\t%s,' % funcdef['name'])
for funcdef in ext['api']:
ret_val.append('\t%s,' % funcdef['name'])
out += ['};\n']
ret_val += ['};\n']
return ret_val
for name in api['extensions']:
out += get_extension_struct_definition(name, api['extensions'][name], False)
out += ['', 'const godot_gdnative_api_struct *gdnative_extensions_pointers[] = {']