[RFC v2 05/12] kunit: mock: add parameter list manipulation macros
From: Daniel Latypov
Date: Mon Oct 12 2020 - 18:21:41 EST
From: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
Add macros for parsing and manipulating parameter lists needed for
generating mocks.
Signed-off-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
Signed-off-by: Daniel Latypov <dlatypov@xxxxxxxxxx>
---
include/kunit/params.h | 305 ++++++++++++++++++++++++++++++++++++
lib/kunit/Makefile | 3 +-
lib/kunit/mock-macro-test.c | 150 ++++++++++++++++++
3 files changed, 457 insertions(+), 1 deletion(-)
create mode 100644 include/kunit/params.h
create mode 100644 lib/kunit/mock-macro-test.c
diff --git a/include/kunit/params.h b/include/kunit/params.h
new file mode 100644
index 000000000000..06efcb58c2c0
--- /dev/null
+++ b/include/kunit/params.h
@@ -0,0 +1,305 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Macros for parsing and manipulating parameter lists needed for generating
+ * mocks.
+ *
+ * Copyright (C) 2020, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
+ */
+
+#ifndef _KUNIT_PARAMS_H
+#define _KUNIT_PARAMS_H
+
+#define NUM_VA_ARGS_IMPL(__dummy, \
+ __1, \
+ __2, \
+ __3, \
+ __4, \
+ __5, \
+ __6, \
+ __7, \
+ __8, \
+ __9, \
+ __10, \
+ __11, \
+ __12, \
+ __13, \
+ __14, \
+ __15, \
+ __16, \
+ __nargs, args...) __nargs
+
+#define NUM_VA_ARGS(args...) NUM_VA_ARGS_IMPL(__dummy, ##args, \
+ 16, \
+ 15, \
+ 14, \
+ 13, \
+ 12, \
+ 11, \
+ 10, \
+ 9, \
+ 8, \
+ 7, \
+ 6, \
+ 5, \
+ 4, \
+ 3, \
+ 2, \
+ 1, \
+ 0)
+
+#define CONCAT_INTERNAL(left, right) left##right
+#define CONCAT(left, right) CONCAT_INTERNAL(left, right)
+
+#define EMPTY()
+
+/*
+ * Takes the name of a function style macro such as FOO() and prevents it from
+ * being evaluated on the current pass.
+ *
+ * This is useful when you need to write a "recursive" macro since a macro name
+ * becomes painted after it is pasted. If a different macro is pasted, this
+ * different macro won't be pasted; if we then defer the evaluation of the this
+ * "indirection macro", we can prevent the original definition from getting
+ * painted.
+ *
+ * Example:
+ * #define EXAMPLE EXPAND(FOO()) // FOO() is evaluated on 1st pass.
+ * #define EXAMPLE EXPAND(DEFER(FOO)()) // FOO() is evaluated on the second
+ * // pass.
+ */
+#define DEFER(macro_id) macro_id EMPTY()
+
+/*
+ * Takes the name of a function style macro such as FOO() and prevents it from
+ * being evaluated on the current or following pass.
+ *
+ * This is useful when you need to DEFER inside an operation which causes an
+ * extra pass, like IF.
+ *
+ * Example:
+ * #define EXAMPLE EXPAND(FOO()) // FOO() is evaluated on 1st pass.
+ * #define EXAMPLE EXPAND(DEFER(FOO)()) // FOO() is evaluated on the second
+ * // pass.
+ * #define EXAMPLE EXPAND(OBSTRUCT(FOO)()) // FOO() is evaluated on the third
+ * // pass.
+ */
+#define OBSTRUCT(macro_id) macro_id DEFER(EMPTY)()
+
+#define EXPAND_1(args...) args
+#define EXPAND_2(args...) EXPAND_1(EXPAND_1(args))
+#define EXPAND_4(args...) EXPAND_2(EXPAND_2(args))
+#define EXPAND_8(args...) EXPAND_4(EXPAND_4(args))
+#define EXPAND_16(args...) EXPAND_8(EXPAND_8(args))
+
+/*
+ * Causes multiple evaluation passes of a macro.
+ *
+ * CPP is implemented as a push down automaton. It consumes a stream of tokens
+ * and as it comes across macros, it either evaluates them and pastes the
+ * result, or if the macro is a function macro, it pushes the macro to a stack,
+ * it evaluates the input to the function macro, pops the state from the stack
+ * and continues.
+ *
+ * This macro serves the function of making the cursor return to the beginging
+ * of a macro that requires mulitple passes to evaluate. It is most useful when
+ * used with DEFER(...) and OBSTRUCT(...).
+ */
+#define EXPAND(args...) EXPAND_16(args)
+
+#define INC(id) INC_##id
+#define INC_0 1
+#define INC_1 2
+#define INC_2 3
+#define INC_3 4
+#define INC_4 5
+#define INC_5 6
+#define INC_6 7
+#define INC_7 8
+#define INC_8 9
+#define INC_9 10
+#define INC_10 11
+#define INC_11 12
+#define INC_12 13
+#define INC_13 14
+#define INC_14 15
+#define INC_15 16
+#define INC_16 17
+
+#define DEC(id) DEC_##id
+#define DEC_1 0
+#define DEC_2 1
+#define DEC_3 2
+#define DEC_4 3
+#define DEC_5 4
+#define DEC_6 5
+#define DEC_7 6
+#define DEC_8 7
+#define DEC_9 8
+#define DEC_10 9
+#define DEC_11 10
+#define DEC_12 11
+#define DEC_13 12
+#define DEC_14 13
+#define DEC_15 14
+#define DEC_16 15
+
+#define DROP_FIRST_ARG_INTERNAL(dropped, x, args...) x
+#define DROP_FIRST_ARG(args...) DROP_FIRST_ARG_INTERNAL(args)
+
+#define EQUAL(left, right) EQUAL_##left##_##right
+#define EQUAL_0_0 dropped, 1
+#define EQUAL_1_1 dropped, 1
+#define EQUAL_2_2 dropped, 1
+#define EQUAL_3_3 dropped, 1
+#define EQUAL_4_4 dropped, 1
+#define EQUAL_5_5 dropped, 1
+#define EQUAL_6_6 dropped, 1
+#define EQUAL_7_7 dropped, 1
+#define EQUAL_8_8 dropped, 1
+#define EQUAL_9_9 dropped, 1
+#define EQUAL_10_10 dropped, 1
+#define EQUAL_11_11 dropped, 1
+#define EQUAL_12_12 dropped, 1
+#define EQUAL_13_13 dropped, 1
+#define EQUAL_14_14 dropped, 1
+#define EQUAL_15_15 dropped, 1
+#define EQUAL_16_16 dropped, 1
+
+#define IS_EQUAL(left, right) DROP_FIRST_ARG(EQUAL(left, right), 0)
+
+#define NOT_INTERNAL(condition) NOT_##condition
+#define NOT(condition) NOT_INTERNAL(condition)
+#define NOT_0 1
+#define NOT_1 0
+
+#define IS_NOT_EQUAL(left, right) NOT(IS_EQUAL(left, right))
+
+#define EMPTY_IMPL(tokens) CONCAT(EMPTY_, tokens)
+#define IS_EMPTY(tokens)
+
+#define OR_INTERNAL(left, right) OR_##left##_##right
+#define OR(left, right) OR_INTERNAL(left, right)
+#define OR_0_0 0
+#define OR_0_1 1
+#define OR_1_0 1
+#define OR_1_1 1
+
+#define IF(condition) CONCAT(IF_, condition)
+#define IF_0(body)
+#define IF_1(body) body
+
+#define COMMA() ,
+
+#define APPLY_TOKENS_INTERNAL(tokens, yield_token, seen_token) \
+ IF(yield_token)(IF(seen_token)(COMMA()) tokens)
+#define APPLY_TOKENS(tokens, yield_token, seen_token) \
+ APPLY_TOKENS_INTERNAL(tokens, yield_token, seen_token)
+
+/*
+ * Provides the indirection to keep the PARAM_LIST_RECURSE_INTERNAL from getting
+ * pasted, only useful if used with DEFER(...) or OBSTRUCT(...).
+ */
+#define PARAM_LIST_RECURSE_INDIRECT() PARAM_LIST_RECURSE_INTERNAL
+
+/*
+ * Given a starting index, a number of args, a MACRO to apply, and a list of
+ * types (with at least one element) this will call MACRO with the first type in
+ * the list and index; it will then call itself again on all remaining types, if
+ * any, while incrementing index, and decrementing nargs.
+ *
+ * Assumes nargs is the number of types in the list.
+ */
+#define PARAM_LIST_RECURSE_INTERNAL(index, \
+ nargs, \
+ MACRO, \
+ FILTER, \
+ context, \
+ seen_token, \
+ type, \
+ args...) \
+ APPLY_TOKENS(MACRO(context, type, index), \
+ FILTER(context, type, index), \
+ seen_token) \
+ IF(IS_NOT_EQUAL(nargs, 1)) \
+ (OBSTRUCT(PARAM_LIST_RECURSE_INDIRECT)() \
+ (INC(index), DEC(nargs), \
+ MACRO, FILTER, context, \
+ OR(seen_token, FILTER(context, type, index)), \
+ args))
+
+#define PARAM_LIST_RECURSE(index, nargs, MACRO, FILTER, context, args...) \
+ IF(IS_NOT_EQUAL(nargs, 0)) \
+ (OBSTRUCT(PARAM_LIST_RECURSE_INTERNAL)(index, \
+ nargs, \
+ MACRO, \
+ FILTER, \
+ context, \
+ 0, \
+ args))
+
+#define FILTER_NONE(context, type, index) 1
+
+#define FILTER_INDEX_INTERNAL(index_to_drop, type, index) \
+ IS_NOT_EQUAL(index, index_to_drop)
+#define FILTER_INDEX(index_to_drop, type, index) \
+ FILTER_INDEX_INTERNAL(index_to_drop, type, index)
+
+/*
+ * Applies a MACRO which takes a type and the index of the type and outputs a
+ * sequence of tokens to a list of types.
+ */
+#define FOR_EACH_PARAM(MACRO, FILTER, context, args...) \
+ EXPAND(PARAM_LIST_RECURSE(0,\
+ NUM_VA_ARGS(args),\
+ MACRO,\
+ FILTER,\
+ context,\
+ args))
+
+#define PRODUCE_TYPE_AND_ARG(context, type, index) type arg##index
+#define PARAM_LIST_FROM_TYPES(args...) \
+ FOR_EACH_PARAM(PRODUCE_TYPE_AND_ARG, \
+ FILTER_NONE, \
+ not_used, \
+ args)
+
+#define PRODUCE_TYPE_NAME(context, type, index) #type
+#define TYPE_NAMES_FROM_TYPES(handle_index, args...) \
+ FOR_EACH_PARAM(PRODUCE_TYPE_NAME, \
+ FILTER_INDEX, \
+ handle_index, \
+ args)
+
+#define PRODUCE_PTR_TO_ARG(context, type, index) &arg##index
+#define PTR_TO_ARG_FROM_TYPES(handle_index, args...) \
+ FOR_EACH_PARAM(PRODUCE_PTR_TO_ARG, \
+ FILTER_INDEX, \
+ handle_index, \
+ args)
+
+#define PRODUCE_MATCHER_AND_ARG(ctrl_index, type, index) \
+ IF(IS_EQUAL(index, ctrl_index))(struct mock *arg##ctrl_index) \
+ IF(IS_NOT_EQUAL(index, ctrl_index))( \
+ struct mock_param_matcher *arg##index)
+#define MATCHER_PARAM_LIST_FROM_TYPES(ctrl_index, args...) \
+ FOR_EACH_PARAM(PRODUCE_MATCHER_AND_ARG, \
+ FILTER_NONE, \
+ ctrl_index, \
+ args)
+
+#define PRODUCE_ARG(context, type, index) arg##index
+#define ARG_NAMES_FROM_TYPES(ctrl_index, args...) \
+ FOR_EACH_PARAM(PRODUCE_ARG, \
+ FILTER_INDEX, \
+ ctrl_index, \
+ args)
+
+#define PRODUCE_ARRAY_ACCESSOR(context, type, index) *((type *) params[index])
+#define ARRAY_ACCESSORS_FROM_TYPES(args...) \
+ FOR_EACH_PARAM(PRODUCE_ARRAY_ACCESSOR, \
+ FILTER_NONE, \
+ not_used, \
+ args)
+
+#endif /* _KUNIT_PARAMS_H */
diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile
index 523a7b0f9783..1707660c8b1c 100644
--- a/lib/kunit/Makefile
+++ b/lib/kunit/Makefile
@@ -10,7 +10,8 @@ ifeq ($(CONFIG_KUNIT_DEBUGFS),y)
kunit-objs += debugfs.o
endif
-obj-$(CONFIG_KUNIT_TEST) += kunit-test.o
+obj-$(CONFIG_KUNIT_TEST) += kunit-test.o \
+ mock-macro-test.o
# string-stream-test compiles built-in only.
ifeq ($(CONFIG_KUNIT_TEST),y)
diff --git a/lib/kunit/mock-macro-test.c b/lib/kunit/mock-macro-test.c
new file mode 100644
index 000000000000..6c3dc2193edb
--- /dev/null
+++ b/lib/kunit/mock-macro-test.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test for parameter list parsing macros.
+ *
+ * Copyright (C) 2020, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
+ */
+
+#include <kunit/test.h>
+#include <kunit/params.h>
+
+#define TO_STR_INTERNAL(...) #__VA_ARGS__
+#define TO_STR(...) TO_STR_INTERNAL(__VA_ARGS__)
+
+static void mock_macro_is_equal(struct kunit *test)
+{
+ KUNIT_EXPECT_STREQ(test, "dropped, 1", TO_STR(EQUAL(1, 1)));
+ KUNIT_EXPECT_EQ(test, 1, DROP_FIRST_ARG(dropped, 1, 0));
+ KUNIT_EXPECT_EQ(test, 0, DROP_FIRST_ARG(1, 0));
+ KUNIT_EXPECT_EQ(test, 0, DROP_FIRST_ARG(EQUAL(1, 0), 0));
+ KUNIT_EXPECT_EQ(test, 1, IS_EQUAL(1, 1));
+ KUNIT_EXPECT_EQ(test, 0, IS_EQUAL(1, 0));
+}
+
+static void mock_macro_if(struct kunit *test)
+{
+ KUNIT_EXPECT_STREQ(test, "body", ""IF(1)("body"));
+ KUNIT_EXPECT_STREQ(test, "", ""IF(0)("body"));
+ KUNIT_EXPECT_STREQ(test, "body", ""IF(IS_EQUAL(1, 1))("body"));
+ KUNIT_EXPECT_STREQ(test, "", ""IF(IS_EQUAL(0, 1))("body"));
+}
+
+static void mock_macro_apply_tokens(struct kunit *test)
+{
+ KUNIT_EXPECT_STREQ(test, "type", TO_STR(APPLY_TOKENS(type, 1, 0)));
+ KUNIT_EXPECT_STREQ(test, ", type", TO_STR(APPLY_TOKENS(type, 1, 1)));
+ KUNIT_EXPECT_STREQ(test, "", TO_STR(APPLY_TOKENS(type, 0, 1)));
+}
+
+#define IDENTITY(context, type, index) type
+
+static void mock_macro_param_list_recurse(struct kunit *test)
+{
+ KUNIT_EXPECT_STREQ(test, "", TO_STR(PARAM_LIST_RECURSE(0,
+ 0,
+ IDENTITY,
+ FILTER_NONE,
+ not_used)));
+ KUNIT_EXPECT_STREQ(test,
+ "type",
+ TO_STR(EXPAND(PARAM_LIST_RECURSE(0,
+ 1,
+ IDENTITY,
+ FILTER_NONE,
+ not_used,
+ type))));
+ KUNIT_EXPECT_STREQ(test,
+ "type0 , type1 , type2 , type3 , type4 , type5 , "
+ "type6 , type7 , type8 , type9 , type10 , type11 , "
+ "type12 , type13 , type14 , type15",
+ TO_STR(EXPAND(PARAM_LIST_RECURSE(0, 16,
+ IDENTITY,
+ FILTER_NONE,
+ not_used,
+ type0, type1, type2,
+ type3, type4, type5,
+ type6, type7, type8,
+ type9, type10,
+ type11, type12,
+ type13, type14,
+ type15))));
+}
+
+static void mock_macro_for_each_param(struct kunit *test)
+{
+ KUNIT_EXPECT_STREQ(test,
+ "type0 , type1",
+ TO_STR(FOR_EACH_PARAM(IDENTITY,
+ FILTER_NONE,
+ not_used,
+ type0,
+ type1)));
+ KUNIT_EXPECT_STREQ(test,
+ "type1",
+ TO_STR(FOR_EACH_PARAM(IDENTITY,
+ FILTER_INDEX,
+ 0,
+ type0,
+ type1)));
+}
+
+static void mock_macro_param_list_from_types_basic(struct kunit *test)
+{
+ KUNIT_EXPECT_STREQ(test, "", TO_STR(PARAM_LIST_FROM_TYPES()));
+ KUNIT_EXPECT_STREQ(test, "int arg0",
+ TO_STR(PARAM_LIST_FROM_TYPES(int)));
+ KUNIT_EXPECT_STREQ(test, "struct kunit_struct * arg0 , int arg1",
+ TO_STR(PARAM_LIST_FROM_TYPES(struct kunit_struct *,
+ int)));
+ KUNIT_EXPECT_STREQ(test,
+ "type0 arg0 , type1 arg1 , type2 arg2 , type3 arg3 , "
+ "type4 arg4 , type5 arg5 , type6 arg6 , type7 arg7 , "
+ "type8 arg8 , type9 arg9 , type10 arg10 , "
+ "type11 arg11 , type12 arg12 , type13 arg13 , "
+ "type14 arg14 , type15 arg15",
+ TO_STR(PARAM_LIST_FROM_TYPES(type0, type1, type2,
+ type3, type4, type5,
+ type6, type7, type8,
+ type9, type10, type11,
+ type12, type13, type14,
+ type15)));
+}
+
+static void mock_macro_arg_names_from_types(struct kunit *test)
+{
+ KUNIT_EXPECT_STREQ(test, "", TO_STR(ARG_NAMES_FROM_TYPES(0)));
+ KUNIT_EXPECT_STREQ(test, "", TO_STR(ARG_NAMES_FROM_TYPES(0, int)));
+ KUNIT_EXPECT_STREQ(test,
+ "arg1",
+ TO_STR(ARG_NAMES_FROM_TYPES(0,
+ struct kunit_struct *,
+ int)));
+ KUNIT_EXPECT_STREQ(test,
+ "arg0 , arg1 , arg3 , arg4 , arg5 , arg6 , arg7 , "
+ "arg8 , arg9 , arg10 , arg11 , arg12 , arg13 , "
+ "arg14 , arg15",
+ TO_STR(ARG_NAMES_FROM_TYPES(2, type0, type1, type2,
+ type3, type4, type5,
+ type6, type7, type8,
+ type9, type10, type11,
+ type12, type13, type14,
+ type15)));
+}
+
+static struct kunit_case mock_macro_test_cases[] = {
+ KUNIT_CASE(mock_macro_is_equal),
+ KUNIT_CASE(mock_macro_if),
+ KUNIT_CASE(mock_macro_apply_tokens),
+ KUNIT_CASE(mock_macro_param_list_recurse),
+ KUNIT_CASE(mock_macro_for_each_param),
+ KUNIT_CASE(mock_macro_param_list_from_types_basic),
+ KUNIT_CASE(mock_macro_arg_names_from_types),
+ {}
+};
+
+static struct kunit_suite mock_macro_test_suite = {
+ .name = "mock-macro-test",
+ .test_cases = mock_macro_test_cases,
+};
+kunit_test_suite(mock_macro_test_suite);
--
2.28.0.1011.ga647a8990f-goog