Commit Graph

256 Commits

Author SHA1 Message Date
Aditya Srivastava
e86bdb2437 scripts: kernel-doc: reduce repeated regex expressions into variables
There are some regex expressions in the kernel-doc script, which are used
repeatedly in the script.

Reduce such expressions into variables, which can be used everywhere.

A quick manual check found that no errors and warnings were added/removed
in this process.

Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Link: https://lore.kernel.org/r/20210514144244.25341-1-yashsri421@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-05-17 11:21:16 -06:00
Matthew Wilcox
80342d484a kernel-doc: Add support for __deprecated
The current linux-next tree has a new error:

./Documentation/gpu/drm-mm:445: ./drivers/gpu/drm/drm_prime.c:994: WARNING: Error in declarator or parameters
Invalid C declaration: Expecting "(" in parameters. [error at 17]
  int __deprecated drm_prime_sg_to_page_array (struct sg_table *sgt, struct page **pages, int max_entries)
  -----------------^

While we might consider that documenting a deprecated interface is not
necessarily best practice, removing the error is easy.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

Link: https://lore.kernel.org/r/20210427114828.GY235567@casper.infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-04-27 09:59:04 -06:00
Aditya Srivastava
f9bbc12ccb scripts: kernel-doc: improve parsing for kernel-doc comments syntax
Currently kernel-doc does not identify some cases of probable kernel
doc comments, for e.g. pointer used as declaration type for identifier,
space separated identifier, etc.

Some example of these cases in files can be:
i)" *  journal_t * jbd2_journal_init_dev() - creates and initialises a journal structure"
in fs/jbd2/journal.c

ii) "*      dget, dget_dlock -      get a reference to a dentry" in
include/linux/dcache.h

iii) "  * DEFINE_SEQLOCK(sl) - Define a statically allocated seqlock_t"
in include/linux/seqlock.h

Also improve identification for non-kerneldoc comments. For e.g.,

i) " *	The following functions allow us to read data using a swap map"
in kernel/power/swap.c does follow the kernel-doc like syntax, but the
content inside does not adheres to the expected format.

Improve parsing by adding support for these probable attempts to write
kernel-doc comment.

Suggested-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/lkml/87mtujktl2.fsf@meer.lwn.net
Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Link: https://lore.kernel.org/r/20210414192529.9080-1-yashsri421@gmail.com
[ jc: fixed some line-length issues ]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-04-15 15:26:06 -06:00
Aditya Srivastava
3e58e83915 scripts: kernel-doc: add warning for comment not following kernel-doc syntax
Currently, kernel-doc start parsing the comment as a kernel-doc comment if
it starts with '/**', but does not take into account if the content inside
the comment too, adheres with the expected format.
This results in unexpected and unclear warnings for the user.

E.g., running scripts/kernel-doc -none mm/memcontrol.c emits:
"mm/memcontrol.c:961: warning: expecting prototype for do not fallback to current(). Prototype was for get_mem_cgroup_from_current() instead"

Here kernel-doc parses the corresponding comment as a kernel-doc comment
and expects prototype for it in the next lines, and as a result causing
this warning.

Provide a clearer warning message to the users regarding the same, if the
content inside the comment does not follow the kernel-doc expected format.

Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Link: https://lore.kernel.org/r/20210329092945.13152-1-yashsri421@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-29 17:08:28 -06:00
Jonathan Corbet
212209cff8 docs: kernel-doc: properly recognize parameter lines with colons
The previous attempt to properly handle literal blocks broke parsing of
parameter lines containing colons; fix it by tweaking the regex to
specifically exclude the "::" pattern while accepting lines containing
colons in general.  Add a little documentation to the regex while in the
neighborhood.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 8d295fbad6 ("kernel-doc: better handle '::' sequences")
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-26 13:16:35 -06:00
Mauro Carvalho Chehab
8d295fbad6 kernel-doc: better handle '::' sequences
Right now, if one of the following headers end with a '::', the
kernel-doc script will do the wrong thing:

	description|context|returns?|notes?|examples?

The real issue is with examples, as people could try to write
something like:

	example::

		/* Some C code */

and this won't be properly evaluated. So, improve the regex
to not catch '\w+::' regex for the above identifiers.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/2cf44cf1fa42588632735d4fbc8e84304bdc235f.1616696051.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-25 12:50:27 -06:00
Mauro Carvalho Chehab
0b54c2e34b scripts/kernel-doc: ignore identifier on anonymous enums
When anonymous enums are used, the identifier is empty.

While, IMO, it should be avoided the usage of such enums,
adding support for it is not hard.

So, postpone the check for empty identifiers to happen
only at the dump phase.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/055ad57879f1b9381b90879e00f72fde1c3a5647.1614760910.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-08 17:10:24 -07:00
Aditya Srivastava
084aa00162 scripts: kernel-doc: fix attribute capture in function parsing
Currently, kernel-doc warns for function prototype parsing on the
presence of attributes "__attribute_const__" and "__flatten" in the
definition.

There are 166 occurrences in ~70 files in the kernel tree for
"__attribute_const__" and 5 occurrences in 4 files for "__flatten".

Out of 166, there are 3 occurrences in three different files with
"__attribute_const__" and a preceding kernel-doc; and, 1 occurrence in
./mm/percpu.c for "__flatten" with a preceding kernel-doc. All other
occurrences have no preceding kernel-doc.

Add support for  "__attribute_const__" and "__flatten" attributes.

A quick evaluation by running 'kernel-doc -none' on kernel-tree reveals
that no additional warning or error has been added or removed by the fix.

Suggested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Link: https://lore.kernel.org/r/20210306113510.31023-1-yashsri421@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-08 16:04:20 -07:00
Aditya Srivastava
a746fe32cd scripts: kernel-doc: fix typedef support for struct/union parsing
Currently, there are ~1290 occurrences in 447 files in the kernel tree
'typedef struct/union' syntax for defining some struct/union. However,
kernel-doc currently does not support that syntax. Of the ~1290
occurrences, there are four occurrences in ./include/linux/zstd.h with
typedef struct/union syntax and a preceding kernel-doc; all other
occurrences have no preceding kernel-doc.

Add support for parsing struct/union following this syntax.

Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Link: https://lore.kernel.org/r/20210225145033.11431-1-yashsri421@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-03-06 17:36:51 -07:00
Aditya Srivastava
336ced2de6 scripts: kernel-doc: fix array element capture in pointer-to-func parsing
Currently, kernel-doc causes an unexpected error when array element (i.e.,
"type (*foo[bar])(args)") is present as pointer parameter in
pointer-to-function parsing.

For e.g., running kernel-doc -none on kernel/gcov/gcc_4_7.c causes this
error:
"Use of uninitialized value $param in regexp compilation at ...", in
combination with:
"warning: Function parameter or member '' not described in 'gcov_info'"

Here, the parameter parsing does not take into account the presence of
array element (i.e. square brackets) in $param.

Provide a simple fix by adding square brackets in the regex, responsible
for capturing $param.

A quick evaluation, by running 'kernel-doc -none' on entire kernel-tree,
reveals that no additional warning or error has been added or removed by
the fix.

Suggested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Tested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20210217145625.14006-1-yashsri421@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-02-22 14:20:36 -07:00
Michal Wajdeczko
06a755d626 scripts/kernel-doc: add internal hyperlink to DOC: sections
While DOC: section titles are not converted into RST headings
sections and are only decorated with strong emphasis markup,
nothing stops us from generating internal hyperlinks for them,
to mimic implicit hyperlinks to RST headings.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://lore.kernel.org/r/20210118110813.1490-1-michal.wajdeczko@intel.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-28 16:35:00 -07:00
Mauro Carvalho Chehab
52042e2db4 scripts: kernel-doc: validate kernel-doc markup with the actual names
Kernel-doc currently expects that the kernel-doc markup to come
just before the function/enum/struct/union/typedef prototype.

Yet, if it find things like:

	/**
	 * refcount_add - add a value to a refcount
	 * @i: the value to add to the refcount
	 * @r: the refcount
	 */
	static inline void __refcount_add(int i, refcount_t *r, int *oldp);
	static inline void refcount_add(int i, refcount_t *r);

Kernel-doc will do the wrong thing:

	foobar.h:6: warning: Function parameter or member 'oldp' not described in '__refcount_add'
	.. c:function:: void __refcount_add (int i, refcount_t *r, int *oldp)

	   add a value to a refcount

	**Parameters**

	``int i``
	  the value to add to the refcount

	``refcount_t *r``
	  the refcount

	``int *oldp``
	  *undescribed*

Basically, it will document "__refcount_add" with the kernel-doc
markup for refcount_add.

If both functions have the same arguments, this won't even
produce any warning!

Add a logic to check if the kernel-doc identifier matches the actual
name of the C function or data structure that will be documented.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/081546f141a496d6cabb99a4adc140444c705e93.1610610937.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-01-18 13:33:26 -07:00
Mauro Carvalho Chehab
7d2c6b1edf scripts: kernel-doc: fix parsing function-like typedefs
Changeset 6b80975c63 ("scripts: kernel-doc: fix typedef parsing")
added support for things like:

	typedef unsigned long foo();

However, it caused a regression on this prototype:

	typedef bool v4l2_check_dv_timings_fnc(const struct v4l2_dv_timings *t, void *handle);

This is only noticed after adding a patch that checks if the
kernel-doc identifier matches the typedef:

	./scripts/kernel-doc -none $(git grep '^.. kernel-doc::' Documentation/ |cut -d ' ' -f 3|sort|uniq) 2>&1|grep expecting
	include/media/v4l2-dv-timings.h:38: warning: expecting prototype for typedef v4l2_check_dv_timings_fnc. Prototype was for typedef nc instead

The problem is that, with the new parsing logic, it is not
checking for complete words at the type part.

Fix it by adding a \b at the end of each type word at the
regex.

fixes: 6b80975c63 ("scripts: kernel-doc: fix typedef parsing")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/218ff56dcb8e73755005d3fb64586eb1841a276b.1606896997.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-03 15:56:14 -07:00
Andy Shevchenko
ae5b17e464 scripts: kernel-doc: Restore anonymous enum parsing
The commit d38c8cfb05 ("scripts: kernel-doc: add support for typedef enum")
broke anonymous enum parsing. Restore it by relying on members rather than
its name.

Fixes: d38c8cfb05 ("scripts: kernel-doc: add support for typedef enum")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Cc: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/20201102170637.36138-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-11-13 15:09:19 -07:00
Mauro Carvalho Chehab
72b97d0b91 scripts: kernel-doc: use :c:union when needed
Sphinx C domain code after 3.2.1 will start complaning if :c:struct
would be used for an union type:

	.../Documentation/gpu/drm-kms-helpers:352: ../drivers/video/hdmi.c:851: WARNING: C 'identifier' cross-reference uses wrong tag: reference name is 'union hdmi_infoframe' but found name is 'struct hdmi_infoframe'. Full reference name is 'union hdmi_infoframe'. Full found name is 'struct hdmi_infoframe'.

So, let's address this issue too in advance, in order to
avoid future issues.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/6e4ec3eec914df62389a299797a3880ae4490f35.1603791716.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-10-28 11:26:09 -06:00
Mauro Carvalho Chehab
7efc6c4295 scripts: kernel-doc: split typedef complex regex
The typedef regex for function prototypes are very complex.
Split them into 3 separate regex and then join them using
qr.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/3a4af999a0d62d4ab9dfae1cdefdfcad93383356.1603792384.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-10-28 11:13:34 -06:00
Mauro Carvalho Chehab
6b80975c63 scripts: kernel-doc: fix typedef parsing
The include/linux/genalloc.h file defined this typedef:

	typedef unsigned long (*genpool_algo_t)(unsigned long *map,unsigned long size,unsigned long start,unsigned int nr,void *data, struct gen_pool *pool, unsigned long start_addr);

Because it has a type composite of two words (unsigned long),
the parser gets the typedef name wrong:

.. c:macro:: long

   **Typedef**: Allocation callback function type definition

Fix the regex in order to accept composite types when
defining a typedef for a function pointer.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/328e8018041cc44f7a1684e57f8d111230761c4f.1603792384.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-10-28 11:13:29 -06:00
Mauro Carvalho Chehab
6e9e415854 scripts: kernel-doc: try to use c:function if possible
There are a few namespace clashes by using c:macro everywhere:

basically, when using it, we can't have something like:

	.. c:struct:: pwm_capture

	.. c:macro:: pwm_capture

So, we need to use, instead:

	.. c:function:: int pwm_capture (struct pwm_device * pwm, struct pwm_capture * result, unsigned long timeout)

for the function declaration.

The kernel-doc change was proposed by Jakob Lykke Andersen here:

	6fd2076ec0

Although I did a different implementation.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:37 +02:00
Mauro Carvalho Chehab
5ef09c96d4 scripts: kernel-doc: fix line number handling
Address several issues related to pointing to the wrong line
number:

1) ensure that line numbers will always be initialized

   When section is the default (Description), the line number
   is not initializing, producing this:

	$ ./scripts/kernel-doc --enable-lineno ./drivers/media/v4l2-core/v4l2-mem2mem.c|less

	**Description**

	#define LINENO 0
	In case of streamoff or release called on any context,
	1] If the context is currently running, then abort job will be called
	2] If the context is queued, then the context will be removed from
	   the job_queue

  Which is not right. Ensure that the line number will always
  be there. After applied, the result now points to the right location:

	**Description**

	#define LINENO 410
	In case of streamoff or release called on any context,
	1] If the context is currently running, then abort job will be called
	2] If the context is queued, then the context will be removed from
	   the job_queue

2) The line numbers for function prototypes are always + 1,
   because it is taken at the line after handling the prototype.
   Change the logic to point to the next line after the /** */
   block;

3) The "DOC:" line number should point to the same line as this
   markup is found, and not to the next one.

Probably part of the issues were due to a but that was causing
the line number offset to be incremented by one, if --export
were used.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:37 +02:00
Mauro Carvalho Chehab
93351d4196 scripts: kernel-doc: allow passing desired Sphinx C domain dialect
When kernel-doc is called via kerneldoc.py, there's no need to
auto-detect the Sphinx version, as the Sphinx module already
knows it. So, add an optional parameter to allow changing the
Sphinx dialect.

As kernel-doc can also be manually called, keep the auto-detection
logic if the parameter was not specified. On such case, emit
a warning if sphinx-build can't be found at PATH.

I ended using a suggestion from Joe for using a more readable
regex, instead of using a complex one with a hidden group like:

	m/^(\d+)\.(\d+)(?:\.?(\d+)?)/

in order to get the optional <patch> argument.

Thanks-to: Joe Perches <joe@perches.com>
Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:36 +02:00
Mauro Carvalho Chehab
ed8348e23a scripts: kernel-doc: don't mangle with parameter list
While kernel-doc needs to parse parameters in order to
identify its name, it shouldn't be touching the type,
as parsing it is very difficult, and errors happen.

One current error is when parsing this parameter:

	const u32 (*tab)[256]

Found at ./lib/crc32.c, on this function:

	u32 __pure crc32_be_generic (u32 crc, unsigned char const *p, size_t len, const u32 (*tab)[256], u32 polynomial);

The current logic mangles it, producing this output:

	const u32 ( *tab

That's something that it is not recognizeable.

So, instead, let's push the argument as-is, and use it
when printing the function prototype and when describing
each argument.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:36 +02:00
Mauro Carvalho Chehab
47bcacfd2b scripts: kernel-doc: fix typedef identification
Some typedef expressions are output as normal functions.

As we need to be clearer about the type with Sphinx 3.x,
detect such cases.

While here, fix a wrongly-indented block.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:36 +02:00
Mauro Carvalho Chehab
eab795ddd8 scripts: kernel-doc: reimplement -nofunction argument
Right now, the build system doesn't use -nofunction, as
it is pretty much useless, because it doesn't consider
the other output modes (extern, internal), working only
with all.

Also, it is limited to exclude functions.

Re-implement it in order to allow excluding any symbols from
the document output, no matter what mode is used.

The parameter was also renamed to "-nosymbol", as it express
better its meaning.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:36 +02:00
Mauro Carvalho Chehab
dbe8ba00e5 scripts: kernel-doc: fix troubles with line counts
There's currently a bug with the way kernel-doc script
counts line numbers that can be seen with:

	$ ./scripts/kernel-doc -rst  -enable-lineno include/linux/math64.h >all && ./scripts/kernel-doc -rst -internal -enable-lineno include/linux/math64.h >int && diff -U0 int all

	--- int	2020-09-28 12:58:08.927486808 +0200
	+++ all	2020-09-28 12:58:08.905486845 +0200
	@@ -1 +1 @@
	-#define LINENO 27
	+#define LINENO 26
	@@ -3 +3 @@
	-#define LINENO 16
	+#define LINENO 15
	@@ -9 +9 @@
	-#define LINENO 17
	+#define LINENO 16
	...

This is happening with perl version 5.30.3, but I'm not
so sure if this is a perl bug, or if this is due to something
else.

In any case, fixing it is easy. Basically, when "-internal"
parameter is used, the process_export_file() function opens the
handle "IN". This makes the line number to be incremented, as the
handler for the main open is also "IN".

Fix the problem by using a different handler for the
main open().

While here, add a missing close for it.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:36 +02:00
Mauro Carvalho Chehab
e3ad05fe6e scripts: kernel-doc: use a less pedantic markup for funcs on Sphinx 3.x
Unfortunately, Sphinx 3.x parser for c functions is too pedantic:

	https://github.com/sphinx-doc/sphinx/issues/8241

While it could be relaxed with some configurations, there are
several corner cases that it would make it hard to maintain,
and will require teaching conf.py about several macros.

So, let's instead use the :c:macro notation. This will
produce an output that it is not as nice as currently, but it
should still be acceptable, and will provide cross-references,
removing thousands of warnings when building with newer
versions of Sphinx.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:35 +02:00