Parsing script

1 files changed, 89 insertions, 0 deletions

diff --git a/src/scripts/ffi_decls.py b/src/scripts/ffi_decls.py
new file mode 100755
index 000000000..70bd8e2cf
--- /dev/null
+++ b/src/scripts/ffi_decls.py
@@ -0,0 +1,89 @@
+#!/usr/bin/python
+
+"""
+Automatically generate declarations for the FFI layer
+
+(C) 2019 Jack Lloyd
+
+Botan is released under the Simplified BSD License (see license.txt)
+"""
+
+from pycparser import c_parser, 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 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']:
+            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 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
+
+        fn_args = [fn_name]
+
+        for param in node.args.params:
+
+            is_ptr = False
+            typ = None
+            if isinstance(param.type, c_ast.PtrDecl):
+                is_ptr = True
+                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)
+
+        print(fn_args)
+
+ast = parse_file(ffi_header, use_cpp=True, cpp_args=['-Ibuild/include', '-std=c89', '-DBOTAN_DLL='])
+v = FuncDefVisitor()
+v.visit(ast)