From: Brendan Higgins brendanhiggins@google.com
A lot of the expectation and assertion infrastructure prints out fairly complicated test failure messages, so add a C++ style log library for for logging test results called `struct kunit_stream`.
kunit_stream allows us to construct a message before we know whether we want to print it out; this can be extremely handy if there is information you might need for a failure message that is easiest to collect in the steps leading up to the actual check.
Note that kunit_stream is distinct from string_stream: whereas string_stream is really just a string builder, kunit_stream is specifically used for constructing expectation/assertion (introduced later in this series) messages to a user of KUnit.
Patch was previously reviewed at https://lore.kernel.org/linux-fsdevel/20190712081744.87097-5-brendanhiggins@... Primary differences are * kunit/ => lib/kunit/ * re-expose string_stream_clear(), which was made static since then
Signed-off-by: Brendan Higgins brendanhiggins@google.com Signed-off-by: Daniel Latypov dlatypov@google.com Cc: Stephen Boyd sboyd@kernel.org --- include/kunit/kunit-stream.h | 94 +++++++++++++++++++++++++++++ include/kunit/string-stream.h | 2 + include/kunit/test.h | 1 + lib/kunit/Makefile | 1 + lib/kunit/kunit-stream.c | 110 ++++++++++++++++++++++++++++++++++ lib/kunit/string-stream.c | 2 +- 6 files changed, 209 insertions(+), 1 deletion(-) create mode 100644 include/kunit/kunit-stream.h create mode 100644 lib/kunit/kunit-stream.c
diff --git a/include/kunit/kunit-stream.h b/include/kunit/kunit-stream.h new file mode 100644 index 000000000000..9a768732a04b --- /dev/null +++ b/include/kunit/kunit-stream.h @@ -0,0 +1,94 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * C++ stream style string formatter and printer used in KUnit for outputting + * KUnit messages. + * + * Copyright (C) 2020, Google LLC. + * Author: Brendan Higgins brendanhiggins@google.com + */ + +#ifndef _KUNIT_KUNIT_STREAM_H +#define _KUNIT_KUNIT_STREAM_H + +#include <linux/types.h> +#include <kunit/string-stream.h> + +struct kunit; + +/** + * struct kunit_stream - a std::stream style string builder. + * + * A std::stream style string builder. Allows messages to be built up and + * printed all at once. Note that the intention is to only use + * &struct kunit_stream to communicate with a user of KUnit, most often to + * communicate something about an expectation or an assertion to the user. If + * you want a similar interface, but aren't sure if this is the right class for + * you to use, you probably want to use the related string_stream class, which + * is allowed for generic string construction in a similar manner. This class is + * really only for the KUnit library to communicate certain kinds of information + * to KUnit users and should not be used by anyone else. + * + * A note on &struct kunit_stream's usage: a kunit_stream will generally + * accompany *one* expectation or assertion. Multiple expectations/assertions + * may be validated concurrently at any given time, even within a single test + * case, so sharing a kunit_stream between expectations/assertions may result in + * unintended consequences. + */ +struct kunit_stream { + /* private: internal use only. */ + struct kunit *test; + struct string_stream *internal_stream; +}; + +/** + * alloc_kunit_stream() - constructs a new &struct kunit_stream. + * @test: The test context object. + * @gfp: The GFP flags to use for internal allocations. + * + * Constructs a new test managed &struct kunit_stream. + */ +struct kunit_stream *alloc_kunit_stream(struct kunit *test, + gfp_t gfp); + +/** + * kunit_stream_add(): adds the formatted input to the internal buffer. + * @kstream: the stream being operated on. + * @fmt: printf style format string to append to stream. + * + * Appends the formatted string, @fmt, to the internal buffer. + */ +void __printf(2, 3) kunit_stream_add(struct kunit_stream *kstream, + const char *fmt, ...); + +/** + * kunit_stream_append(): appends the contents of @other to @kstream. + * @kstream: the stream to which @other is appended. + * @other: the stream whose contents are appended to @kstream. + * + * Appends the contents of @other to @kstream. + */ +void kunit_stream_append(struct kunit_stream *kstream, + struct kunit_stream *other); + +/** + * kunit_stream_commit(): prints out the internal buffer to the user. + * @kstream: the stream being operated on. + * + * Outputs the contents of the internal buffer as a kunit_printk formatted + * output. KUNIT_STREAM ONLY OUTPUTS ITS BUFFER TO THE USER IF COMMIT IS + * CALLED!!! The reason for this is that it allows us to construct a message + * before we know whether we want to print it out; this can be extremely handy + * if there is information you might need for a failure message that is easiest + * to collect in the steps leading up to the actual check. + */ +void kunit_stream_commit(struct kunit_stream *kstream); + +/** + * kunit_stream_clear(): clears the internal buffer. + * @kstream: the stream being operated on. + * + * Clears the contents of the internal buffer. + */ +void kunit_stream_clear(struct kunit_stream *kstream); + +#endif /* _KUNIT_KUNIT_STREAM_H */ diff --git a/include/kunit/string-stream.h b/include/kunit/string-stream.h index fe98a00b75a9..44677c386890 100644 --- a/include/kunit/string-stream.h +++ b/include/kunit/string-stream.h @@ -46,6 +46,8 @@ int string_stream_append(struct string_stream *stream,
bool string_stream_is_empty(struct string_stream *stream);
+void string_stream_clear(struct string_stream *stream); + int string_stream_destroy(struct string_stream *stream);
#endif /* _KUNIT_STRING_STREAM_H */ diff --git a/include/kunit/test.h b/include/kunit/test.h index 59f3144f009a..687782fa44d9 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -10,6 +10,7 @@ #define _KUNIT_TEST_H
#include <kunit/assert.h> +#include <kunit/kunit-stream.h> #include <kunit/try-catch.h> #include <linux/kernel.h> #include <linux/module.h> diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile index 724b94311ca3..523a7b0f9783 100644 --- a/lib/kunit/Makefile +++ b/lib/kunit/Makefile @@ -3,6 +3,7 @@ obj-$(CONFIG_KUNIT) += kunit.o kunit-objs += test.o \ string-stream.o \ assert.o \ + kunit-stream.o \ try-catch.o
ifeq ($(CONFIG_KUNIT_DEBUGFS),y) diff --git a/lib/kunit/kunit-stream.c b/lib/kunit/kunit-stream.c new file mode 100644 index 000000000000..744798693f39 --- /dev/null +++ b/lib/kunit/kunit-stream.c @@ -0,0 +1,110 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * C++ stream style string formatter and printer used in KUnit for outputting + * KUnit messages. + * + * Copyright (C) 2020, Google LLC. + * Author: Brendan Higgins brendanhiggins@google.com + */ + +#include <kunit/test.h> +#include <kunit/kunit-stream.h> +#include <kunit/string-stream.h> + +void kunit_stream_add(struct kunit_stream *kstream, const char *fmt, ...) +{ + va_list args; + struct string_stream *stream = kstream->internal_stream; + + va_start(args, fmt); + + if (string_stream_vadd(stream, fmt, args)) + kunit_err(kstream->test, + "Failed to allocate fragment: %s\n", + fmt); + + va_end(args); +} + +void kunit_stream_append(struct kunit_stream *kstream, + struct kunit_stream *other) +{ + int ret; + + ret = string_stream_append(kstream->internal_stream, + other->internal_stream); + + if (ret) + kunit_err(kstream->test, + "Failed to append other stream: %d\n", ret); +} + +void kunit_stream_clear(struct kunit_stream *kstream) +{ + string_stream_clear(kstream->internal_stream); +} + +void kunit_stream_commit(struct kunit_stream *kstream) +{ + struct string_stream *stream = kstream->internal_stream; + struct string_stream_fragment *fragment; + struct kunit *test = kstream->test; + char *buf; + + buf = string_stream_get_string(stream); + if (!buf) { + kunit_err(test, + "Could not allocate buffer, dumping stream:\n"); + list_for_each_entry(fragment, &stream->fragments, node) { + kunit_err(test, "%s", fragment->fragment); + } + kunit_err(test, "\n"); + } else { + kunit_err(test, "%s", buf); + } + + kunit_stream_clear(kstream); +} + +struct kunit_stream_alloc_context { + struct kunit *test; + gfp_t gfp; +}; + +static int kunit_stream_init(struct kunit_resource *res, void *context) +{ + struct kunit_stream_alloc_context *ctx = context; + struct kunit_stream *stream; + + stream = kunit_kzalloc(ctx->test, sizeof(*stream), ctx->gfp); + if (!stream) + return -ENOMEM; + + stream->test = ctx->test; + stream->internal_stream = alloc_string_stream(ctx->test, ctx->gfp); + if (!stream->internal_stream) + return -ENOMEM; + + res->data = stream; + return 0; +} + +static void kunit_stream_free(struct kunit_resource *res) +{ + /* Do nothing because cleanup is handled by KUnit managed resources */ +} + +struct kunit_stream *alloc_kunit_stream(struct kunit *test, + gfp_t gfp) +{ + struct kunit_stream_alloc_context ctx = { + .test = test, + .gfp = gfp + }; + + return kunit_alloc_resource(test, + kunit_stream_init, + kunit_stream_free, + gfp, + &ctx); +} diff --git a/lib/kunit/string-stream.c b/lib/kunit/string-stream.c index 151a0e7ac349..a94004134928 100644 --- a/lib/kunit/string-stream.c +++ b/lib/kunit/string-stream.c @@ -112,7 +112,7 @@ int string_stream_add(struct string_stream *stream, const char *fmt, ...) return result; }
-static void string_stream_clear(struct string_stream *stream) +void string_stream_clear(struct string_stream *stream) { struct string_stream_fragment *frag_container, *frag_container_safe;