+ case OP_OBJC_SELECTOR:
+ { /* Objective C @selector operator. */
+ char *sel = &exp->elts[pc + 2].string;
+ int len = longest_to_int (exp->elts[pc + 1].longconst);
+
+ (*pos) += 3 + BYTES_TO_EXP_ELEM (len + 1);
+ if (noside == EVAL_SKIP)
+ goto nosideret;
+
+ if (sel[len] != 0)
+ sel[len] = 0; /* Make sure it's terminated. */
+ return value_from_longest (lookup_pointer_type (builtin_type_void),
+ lookup_child_selector (sel));
+ }
+
+ case OP_OBJC_MSGCALL:
+ { /* Objective C message (method) call. */
+
+ static CORE_ADDR responds_selector = 0;
+ static CORE_ADDR method_selector = 0;
+
+ CORE_ADDR selector = 0;
+
+ int using_gcc = 0;
+ int struct_return = 0;
+ int sub_no_side = 0;
+
+ static struct value *msg_send = NULL;
+ static struct value *msg_send_stret = NULL;
+ static int gnu_runtime = 0;
+
+ struct value *target = NULL;
+ struct value *method = NULL;
+ struct value *called_method = NULL;
+
+ struct type *selector_type = NULL;
+
+ struct value *ret = NULL;
+ CORE_ADDR addr = 0;
+
+ selector = exp->elts[pc + 1].longconst;
+ nargs = exp->elts[pc + 2].longconst;
+ argvec = (struct value **) alloca (sizeof (struct value *)
+ * (nargs + 5));
+
+ (*pos) += 3;
+
+ selector_type = lookup_pointer_type (builtin_type_void);
+ if (noside == EVAL_AVOID_SIDE_EFFECTS)
+ sub_no_side = EVAL_NORMAL;
+ else
+ sub_no_side = noside;
+
+ target = evaluate_subexp (selector_type, exp, pos, sub_no_side);
+
+ if (value_as_long (target) == 0)
+ return value_from_longest (builtin_type_long, 0);
+
+ if (lookup_minimal_symbol ("objc_msg_lookup", 0, 0))
+ gnu_runtime = 1;
+
+ /* Find the method dispatch (Apple runtime) or method lookup
+ (GNU runtime) function for Objective-C. These will be used
+ to lookup the symbol information for the method. If we
+ can't find any symbol information, then we'll use these to
+ call the method, otherwise we can call the method
+ directly. The msg_send_stret function is used in the special
+ case of a method that returns a structure (Apple runtime
+ only). */
+ if (gnu_runtime)
+ {
+ struct type *type;
+ type = lookup_pointer_type (builtin_type_void);
+ type = lookup_function_type (type);
+ type = lookup_pointer_type (type);
+ type = lookup_function_type (type);
+ type = lookup_pointer_type (type);
+
+ msg_send = find_function_in_inferior ("objc_msg_lookup");
+ msg_send_stret = find_function_in_inferior ("objc_msg_lookup");
+
+ msg_send = value_from_pointer (type, value_as_address (msg_send));
+ msg_send_stret = value_from_pointer (type,
+ value_as_address (msg_send_stret));
+ }
+ else
+ {
+ msg_send = find_function_in_inferior ("objc_msgSend");
+ /* Special dispatcher for methods returning structs */
+ msg_send_stret = find_function_in_inferior ("objc_msgSend_stret");
+ }
+
+ /* Verify the target object responds to this method. The
+ standard top-level 'Object' class uses a different name for
+ the verification method than the non-standard, but more
+ often used, 'NSObject' class. Make sure we check for both. */
+
+ responds_selector = lookup_child_selector ("respondsToSelector:");
+ if (responds_selector == 0)
+ responds_selector = lookup_child_selector ("respondsTo:");
+
+ if (responds_selector == 0)
+ error (_("no 'respondsTo:' or 'respondsToSelector:' method"));
+
+ method_selector = lookup_child_selector ("methodForSelector:");
+ if (method_selector == 0)
+ method_selector = lookup_child_selector ("methodFor:");
+
+ if (method_selector == 0)
+ error (_("no 'methodFor:' or 'methodForSelector:' method"));
+
+ /* Call the verification method, to make sure that the target
+ class implements the desired method. */
+
+ argvec[0] = msg_send;
+ argvec[1] = target;
+ argvec[2] = value_from_longest (builtin_type_long, responds_selector);
+ argvec[3] = value_from_longest (builtin_type_long, selector);
+ argvec[4] = 0;
+
+ ret = call_function_by_hand (argvec[0], 3, argvec + 1);
+ if (gnu_runtime)
+ {
+ /* Function objc_msg_lookup returns a pointer. */
+ argvec[0] = ret;
+ ret = call_function_by_hand (argvec[0], 3, argvec + 1);
+ }
+ if (value_as_long (ret) == 0)
+ error (_("Target does not respond to this message selector."));
+
+ /* Call "methodForSelector:" method, to get the address of a
+ function method that implements this selector for this
+ class. If we can find a symbol at that address, then we
+ know the return type, parameter types etc. (that's a good
+ thing). */
+
+ argvec[0] = msg_send;
+ argvec[1] = target;
+ argvec[2] = value_from_longest (builtin_type_long, method_selector);
+ argvec[3] = value_from_longest (builtin_type_long, selector);
+ argvec[4] = 0;
+
+ ret = call_function_by_hand (argvec[0], 3, argvec + 1);
+ if (gnu_runtime)
+ {
+ argvec[0] = ret;
+ ret = call_function_by_hand (argvec[0], 3, argvec + 1);
+ }
+
+ /* ret should now be the selector. */
+
+ addr = value_as_long (ret);
+ if (addr)
+ {
+ struct symbol *sym = NULL;
+ /* Is it a high_level symbol? */
+
+ sym = find_pc_function (addr);
+ if (sym != NULL)
+ method = value_of_variable (sym, 0);
+ }
+
+ /* If we found a method with symbol information, check to see
+ if it returns a struct. Otherwise assume it doesn't. */
+
+ if (method)
+ {
+ struct block *b;
+ CORE_ADDR funaddr;
+ struct type *value_type;
+
+ funaddr = find_function_addr (method, &value_type);
+
+ b = block_for_pc (funaddr);
+
+ /* If compiled without -g, assume GCC 2. */
+ using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b));
+
+ CHECK_TYPEDEF (value_type);
+
+ if ((value_type == NULL)
+ || (TYPE_CODE(value_type) == TYPE_CODE_ERROR))
+ {
+ if (expect_type != NULL)
+ value_type = expect_type;
+ }
+
+ struct_return = using_struct_return (value_type, using_gcc);
+ }
+ else if (expect_type != NULL)
+ {
+ struct_return = using_struct_return (check_typedef (expect_type), using_gcc);
+ }
+
+ /* Found a function symbol. Now we will substitute its
+ value in place of the message dispatcher (obj_msgSend),
+ so that we call the method directly instead of thru
+ the dispatcher. The main reason for doing this is that
+ we can now evaluate the return value and parameter values
+ according to their known data types, in case we need to
+ do things like promotion, dereferencing, special handling
+ of structs and doubles, etc.
+
+ We want to use the type signature of 'method', but still
+ jump to objc_msgSend() or objc_msgSend_stret() to better
+ mimic the behavior of the runtime. */
+
+ if (method)
+ {
+ if (TYPE_CODE (value_type (method)) != TYPE_CODE_FUNC)
+ error (_("method address has symbol information with non-function type; skipping"));
+ if (struct_return)
+ VALUE_ADDRESS (method) = value_as_address (msg_send_stret);
+ else
+ VALUE_ADDRESS (method) = value_as_address (msg_send);
+ called_method = method;
+ }
+ else
+ {
+ if (struct_return)
+ called_method = msg_send_stret;
+ else
+ called_method = msg_send;
+ }
+
+ if (noside == EVAL_SKIP)
+ goto nosideret;
+
+ if (noside == EVAL_AVOID_SIDE_EFFECTS)
+ {
+ /* If the return type doesn't look like a function type,
+ call an error. This can happen if somebody tries to
+ turn a variable into a function call. This is here
+ because people often want to call, eg, strcmp, which
+ gdb doesn't know is a function. If gdb isn't asked for
+ it's opinion (ie. through "whatis"), it won't offer
+ it. */
+
+ struct type *type = value_type (called_method);
+ if (type && TYPE_CODE (type) == TYPE_CODE_PTR)
+ type = TYPE_TARGET_TYPE (type);
+ type = TYPE_TARGET_TYPE (type);
+
+ if (type)
+ {
+ if ((TYPE_CODE (type) == TYPE_CODE_ERROR) && expect_type)
+ return allocate_value (expect_type);
+ else
+ return allocate_value (type);
+ }
+ else
+ error (_("Expression of type other than \"method returning ...\" used as a method"));
+ }
+
+ /* Now depending on whether we found a symbol for the method,
+ we will either call the runtime dispatcher or the method
+ directly. */
+
+ argvec[0] = called_method;
+ argvec[1] = target;
+ argvec[2] = value_from_longest (builtin_type_long, selector);
+ /* User-supplied arguments. */
+ for (tem = 0; tem < nargs; tem++)
+ argvec[tem + 3] = evaluate_subexp_with_coercion (exp, pos, noside);
+ argvec[tem + 3] = 0;
+
+ if (gnu_runtime && (method != NULL))
+ {
+ /* Function objc_msg_lookup returns a pointer. */
+ deprecated_set_value_type (argvec[0],
+ lookup_function_type (lookup_pointer_type (value_type (argvec[0]))));
+ argvec[0] = call_function_by_hand (argvec[0], nargs + 2, argvec + 1);
+ }
+
+ ret = call_function_by_hand (argvec[0], nargs + 2, argvec + 1);
+ return ret;
+ }
+ break;
+
projects / deliverable / binutils-gdb.git / blobdiff