On 8/4/22 2:58 AM, Maíra Canal wrote:
> Currently, in order to compare memory blocks in KUnit, the KUNIT_EXPECT_EQ
> or KUNIT_EXPECT_FALSE macros are used in conjunction with the memcmp
> function, such as:
> KUNIT_EXPECT_EQ(test, memcmp(foo, bar, size), 0);
>
> Although this usage produces correct results for the test cases, when
> the expectation fails, the error message is not very helpful,
> indicating only the return of the memcmp function.
>
> Therefore, create a new set of macros KUNIT_EXPECT_MEMEQ and
> KUNIT_EXPECT_MEMNEQ that compare memory blocks until a specified size.
> In case of expectation failure, those macros print the hex dump of the
> memory blocks, making it easier to debug test failures for memory blocks.
>
> That said, the expectation
>
> KUNIT_EXPECT_EQ(test, memcmp(foo, bar, size), 0);
>
> would translate to the expectation
>
> KUNIT_EXPECT_MEMEQ(test, foo, bar, size);
>
> Signed-off-by: Maíra Canal <mairacanal@xxxxxxxxxx>
> Reviewed-by: Daniel Latypov <dlatypov@xxxxxxxxxx>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
> ---
> v1 -> v2:
> - Change "determinated" to "specified" (Daniel Latypov).
> - Change the macro KUNIT_EXPECT_ARREQ to KUNIT_EXPECT_MEMEQ, in order to make
> it easier for users to infer the right size unit (Daniel Latypov).
> - Mark the different bytes on the failure message with a <> (Daniel Latypov).
>
> v2 -> v3:
> - Make the bytes aligned at output.
> - Add KUNIT_SUBSUBTEST_INDENT to the output for the indentation (Daniel Latypov).
> - Line up the trailing \ at macros using tabs (Daniel Latypov).
> - Line up the params to the functions (Daniel Latypov).
> ---
> include/kunit/assert.h | 34 +++++++++++++++++++
> include/kunit/test.h | 76 ++++++++++++++++++++++++++++++++++++++++++
> lib/kunit/assert.c | 56 +++++++++++++++++++++++++++++++
> 3 files changed, 166 insertions(+)
>
> diff --git a/include/kunit/assert.h b/include/kunit/assert.h
> index 4b52e12c2ae8..4b817a8eb619 100644
> --- a/include/kunit/assert.h
> +++ b/include/kunit/assert.h
> @@ -256,4 +256,38 @@ void kunit_binary_str_assert_format(const struct kunit_assert *assert,
> const struct va_format *message,
> struct string_stream *stream);
>
> +#define KUNIT_INIT_MEM_ASSERT_STRUCT(text_, left_val, right_val, size_) \
> + { \
> + .assert = { .format = kunit_mem_assert_format }, \
> + .text = text_, \
> + .left_value = left_val, \
> + .right_value = right_val, .size = size_, \
> + }
> +
> +/**
> + * struct kunit_mem_assert - An expectation/assertion that compares two
> + * memory blocks.
> + * @assert: The parent of this type.
> + * @text: Holds the textual representations of the operands and comparator.
> + * @left_value: The actual evaluated value of the expression in the left slot.
> + * @right_value: The actual evaluated value of the expression in the right slot.
> + * @size: Size of the memory block analysed in bytes.
> + *
> + * Represents an expectation/assertion that compares two memory blocks. For
> + * example, to expect that the first three bytes of foo is equal to the
> + * first three bytes of bar, you can use the expectation
> + * KUNIT_EXPECT_MEMEQ(test, foo, bar, 3);
> + */
> +struct kunit_mem_assert {
> + struct kunit_assert assert;
> + const struct kunit_binary_assert_text *text;
> + const void *left_value;
> + const void *right_value;
> + const size_t size;
> +};
> +
> +void kunit_mem_assert_format(const struct kunit_assert *assert,
> + const struct va_format *message,
> + struct string_stream *stream);
> +
> #endif /* _KUNIT_ASSERT_H */
> diff --git a/include/kunit/test.h b/include/kunit/test.h
> index 8ffcd7de9607..02eeaff1c58e 100644
> --- a/include/kunit/test.h
> +++ b/include/kunit/test.h
> @@ -684,6 +684,36 @@ do { \
> ##__VA_ARGS__); \
> } while (0)
>
> +#define KUNIT_MEM_ASSERTION(test, \
> + assert_type, \
> + left, \
> + op, \
> + right, \
> + size, \
> + fmt, \
> + ...) \
> +do { \
> + const void *__left = (left); \
> + const void *__right = (right); \
> + const size_t __size = (size); \
> + static const struct kunit_binary_assert_text __text = { \
> + .operation = #op, \
> + .left_text = #left, \
> + .right_text = #right, \
> + }; \
> + \
> + KUNIT_ASSERTION(test, \
> + assert_type, \
> + memcmp(__left, __right, __size) op 0, \
> + kunit_mem_assert, \
> + KUNIT_INIT_MEM_ASSERT_STRUCT(&__text, \
> + __left, \
> + __right, \
> + __size), \
> + fmt, \
> + ##__VA_ARGS__); \
> +} while (0)
> +
> #define KUNIT_PTR_NOT_ERR_OR_NULL_MSG_ASSERTION(test, \
> assert_type, \
> ptr, \
> @@ -952,6 +982,52 @@ do { \
> fmt, \
> ##__VA_ARGS__)
>
> +/**
> + * KUNIT_EXPECT_MEMEQ() - Expects that the first @size bytes of @left and @right are equal.
> + * @test: The test context object.
> + * @left: An arbitrary expression that evaluates to the specified size.
> + * @right: An arbitrary expression that evaluates to the specified size.
> + * @size: Number of bytes compared.
> + *
> + * Sets an expectation that the values that @left and @right evaluate to are
> + * equal. This is semantically equivalent to
> + * KUNIT_EXPECT_TRUE(@test, !memcmp((@left), (@right), (@size))). See
> + * KUNIT_EXPECT_TRUE() for more information.
> + */
> +#define KUNIT_EXPECT_MEMEQ(test, left, right, size) \
> + KUNIT_EXPECT_MEMEQ_MSG(test, left, right, size, NULL)
> +
> +#define KUNIT_EXPECT_MEMEQ_MSG(test, left, right, size, fmt, ...) \
> + KUNIT_MEM_ASSERTION(test, \
> + KUNIT_EXPECTATION, \
> + left, ==, right, \
> + size, \
> + fmt, \
> + ##__VA_ARGS__)
> +
> +/**
> + * KUNIT_EXPECT_MEMNEQ() - Expects that the first @size bytes of @left and @right are not equal.
> + * @test: The test context object.
> + * @left: An arbitrary expression that evaluates to the specified size.
> + * @right: An arbitrary expression that evaluates to the specified size.
> + * @size: Number of bytes compared.
> + *
> + * Sets an expectation that the values that @left and @right evaluate to are
> + * not equal. This is semantically equivalent to
> + * KUNIT_EXPECT_TRUE(@test, memcmp((@left), (@right), (@size))). See
> + * KUNIT_EXPECT_TRUE() for more information.
> + */
> +#define KUNIT_EXPECT_MEMNEQ(test, left, right, size) \
> + KUNIT_EXPECT_MEMNEQ_MSG(test, left, right, size, NULL)
> +
> +#define KUNIT_EXPECT_MEMNEQ_MSG(test, left, right, size, fmt, ...) \
> + KUNIT_MEM_ASSERTION(test, \
> + KUNIT_EXPECTATION, \
> + left, !=, right, \
> + size, \
> + fmt, \
> + ##__VA_ARGS__)
> +
> /**
> * KUNIT_EXPECT_NULL() - Expects that @ptr is null.
> * @test: The test context object.
> diff --git a/lib/kunit/assert.c b/lib/kunit/assert.c
> index d00d6d181ee8..c346a8d7fa6e 100644
> --- a/lib/kunit/assert.c
> +++ b/lib/kunit/assert.c
> @@ -204,3 +204,59 @@ void kunit_binary_str_assert_format(const struct kunit_assert *assert,
> kunit_assert_print_msg(message, stream);
> }
> EXPORT_SYMBOL_GPL(kunit_binary_str_assert_format);
> +
> +/* Adds a hexdump of a buffer to a string_stream comparing it with
> + * a second buffer. The different bytes are marked with <>.
> + */
> +static void kunit_assert_hexdump(struct string_stream *stream,
> + const void *buf,
> + const void *compared_buf,
> + const size_t len)
> +{
> + size_t i;
> + const u8 *buf1 = buf;
> + const u8 *buf2 = compared_buf;
> +
> + string_stream_add(stream, KUNIT_SUBSUBTEST_INDENT);
> +
> + for (i = 0; i < len; ++i) {
> + if (!(i % 16) && i)
> + string_stream_add(stream, "\n" KUNIT_SUBSUBTEST_INDENT);
> +
> + if (buf1[i] != buf2[i])
> + string_stream_add(stream, "<%02x>", buf1[i]);
> + else
> + string_stream_add(stream, " %02x ", buf1[i]);
> + }
> +}
> +
> +void kunit_mem_assert_format(const struct kunit_assert *assert,
> + const struct va_format *message,
> + struct string_stream *stream)
> +{
> + struct kunit_mem_assert *mem_assert;
> +
> + mem_assert = container_of(assert, struct kunit_mem_assert,
> + assert);
> +
> + string_stream_add(stream,
> + KUNIT_SUBTEST_INDENT "Expected %s %s %s, but\n",
> + mem_assert->text->left_text,
> + mem_assert->text->operation,
> + mem_assert->text->right_text);
> +
> + string_stream_add(stream, KUNIT_SUBSUBTEST_INDENT "%s ==\n",
> + mem_assert->text->left_text);
> + kunit_assert_hexdump(stream, mem_assert->left_value,
> + mem_assert->right_value, mem_assert->size);
> +
> + string_stream_add(stream, "\n");
> +
> + string_stream_add(stream, KUNIT_SUBSUBTEST_INDENT "%s ==\n",
> + mem_assert->text->right_text);
> + kunit_assert_hexdump(stream, mem_assert->right_value,
> + mem_assert->left_value, mem_assert->size);
> +
> + kunit_assert_print_msg(message, stream);
> +}
> +EXPORT_SYMBOL_GPL(kunit_mem_assert_format);
> --
> 2.37.1
>
--
Muhammad Usama Anjum
