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#!/usr/bin/env python3
"""
Automatically generate declarations for the FFI layer
(C) 2019, 2023 Jack Lloyd
Botan is released under the Simplified BSD License (see license.txt)
"""
import traceback
from pycparser import c_ast, parse_file
ffi_header = 'src/lib/ffi/ffi.h'
def to_ctype(typ, is_ptr):
if typ.startswith('botan_') and typ.endswith('_t'):
return 'c_void_p'
if typ == 'botan_view_ctx':
return 'c_void_p'
if typ == 'botan_view_bin_fn':
return 'VIEW_BIN_CALLBACK'
if typ == 'botan_view_str_fn':
return 'VIEW_STR_CALLBACK'
if is_ptr is False:
if typ == 'uint32':
return 'c_uint32'
elif typ == 'size_t':
return 'c_size_t'
elif typ == 'uint8_t':
return 'c_uint8'
elif typ == 'uint32_t':
return 'c_uint32'
elif typ == 'uint64_t':
return 'c_uint64'
elif typ == 'int':
return 'c_int'
elif typ == 'unsigned':
return 'c_uint'
else:
if typ == 'void':
return 'c_void_p'
elif typ in ['char', 'uint8_t']: # hack
return 'c_char_p'
elif typ == 'size_t':
return 'POINTER(c_size_t)'
#elif typ == 'uint8_t':
# return 'POINTER(c_uint8)'
elif typ == 'uint32_t':
return 'POINTER(c_uint32)'
elif typ == 'uint64_t':
return 'POINTER(c_uint64)'
elif typ == 'int':
return 'POINTER(c_int)'
raise Exception("Unknown type %s/%d" % (typ, is_ptr))
class FuncDefVisitor(c_ast.NodeVisitor):
def __init__(self):
self.fn_decls = []
def emit_decls(self):
decls = ''
for (fn_name, fn_args) in self.fn_decls:
decl = " ffi_api(dll.%s," % (fn_name)
if len(fn_args) > 4:
decl += "\n "
else:
decl += ' '
decl += '[' + ', '.join(fn_args) + '])\n'
decls += decl
return decls
def visit_FuncDecl(self, node):
if not isinstance(node.type, c_ast.TypeDecl):
#print("ignoring", node.type)
return
if node.type.type.names != ['int']:
#print("ignoring", node.type)
return
# all functions returning ints:
fn_name = node.type.declname
ignored = [
'botan_view_bin_fn',
'botan_view_str_fn',
'botan_same_mem', # deprecated
'botan_mceies_encrypt', # dead
'botan_mceies_decrypt', # dead
'botan_rng_init_custom', # fixme
]
if fn_name in ignored:
return
fn_args = []
try:
for param in node.args.params:
is_ptr = False
typ = None
if isinstance(param.type, c_ast.PtrDecl):
is_ptr = True
if isinstance(param.type.type, c_ast.PtrDecl):
typ = param.type.type.type.type.names[0]
else:
typ = param.type.type.type.names[0]
elif isinstance(param.type, c_ast.ArrayDecl):
is_ptr = True
typ = param.type.type.type.names[0]
else:
typ = param.type.type.names[0]
ctype = to_ctype(typ, is_ptr)
fn_args.append(ctype)
self.fn_decls.append((fn_name, fn_args))
except Exception as e:
print(traceback.format_exc())
print("FAILED for '%s': %s" % (fn_name, e))
ast = parse_file(ffi_header, use_cpp=True, cpp_args=['-Ibuild/include', '-std=c89', '-DBOTAN_DLL=', '-DBOTAN_NO_DEPRECATED_WARNINGS'])
#print(ast)
v = FuncDefVisitor()
v.visit(ast)
#print("\n".join(v.fn_decls))
print(v.emit_decls())