[libcamera-devel,v2] clang-format: Regroup sort orders
diff mbox series

Message ID 20210809161425.1885984-1-kieran.bingham@ideasonboard.com
State Accepted
Headers show
Series
  • [libcamera-devel,v2] clang-format: Regroup sort orders
Related show

Commit Message

Kieran Bingham Aug. 9, 2021, 4:14 p.m. UTC
Utilise the clang-format header sort to provide a regex based pattern
match for our header inclusion coding style.

Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
---
A sample of all headers from the project (+ a couple of extra tests)
parsed through this can be seen at 
   https://paste.ubuntu.com/p/Bt87C6M77y/

This was generated by:
 git grep -h "^#include" | sort | uniq  > all-headers.cpp
 git add all-headers.cpp
 git commit all-headers.cpp -m "Header Test"
 ./utils/checkstyle.py | patch -p0

While some false positives are visible in this list
 (for instance <camera_metadata_hidden.h> in c/system headers section)
this provides a great deal of the checks automatically, and the
remaining cases may have to be spotted during review.

 .clang-format                  | 49 +++++++++++++++++++++++++++++++---
 Documentation/coding-style.rst | 20 +++++++++++---
 2 files changed, 62 insertions(+), 7 deletions(-)

Comments

Jean-Michel Hautbois Aug. 9, 2021, 4:20 p.m. UTC | #1
Hi Kieran,

On 09/08/2021 18:14, Kieran Bingham wrote:
> Utilise the clang-format header sort to provide a regex based pattern
> match for our header inclusion coding style.
> 
> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
> ---
> A sample of all headers from the project (+ a couple of extra tests)
> parsed through this can be seen at 
>    https://paste.ubuntu.com/p/Bt87C6M77y/
> 
> This was generated by:
>  git grep -h "^#include" | sort | uniq  > all-headers.cpp
>  git add all-headers.cpp
>  git commit all-headers.cpp -m "Header Test"
>  ./utils/checkstyle.py | patch -p0
> 
> While some false positives are visible in this list
>  (for instance <camera_metadata_hidden.h> in c/system headers section)
> this provides a great deal of the checks automatically, and the
> remaining cases may have to be spotted during review.
> 
>  .clang-format                  | 49 +++++++++++++++++++++++++++++++---
>  Documentation/coding-style.rst | 20 +++++++++++---
>  2 files changed, 62 insertions(+), 7 deletions(-)
> 
> diff --git a/.clang-format b/.clang-format
> index 3a8a896e373d..56cfbfa1bec4 100644
> --- a/.clang-format
> +++ b/.clang-format
> @@ -66,10 +66,53 @@ ExperimentalAutoDetectBinPacking: false
>  FixNamespaceComments: true
>  ForEachMacros:
>    - 'udev_list_entry_foreach'
> -IncludeBlocks: Preserve
> +SortIncludes: true
> +IncludeBlocks: Regroup
>  IncludeCategories:
> -  - Regex: '.*'
> -    Priority: 1
> +  # Headers matching the name of the component are matched automatically.
> +  # Priority 1
> +  # Headers in <> with an extension. (+system libraries)
> +  - Regex:           '<([A-Za-z0-9\-_])+\.h>'
> +    Priority:        2 
> +  - Regex:           '<sys/.*>'
> +    Priority:        2
> +  # Qt includes (match before C++ standard library)
> +  - Regex:           '<Q([A-Za-z0-9\-_])+>'
> +    Priority:        10
> +    CaseSensitive:   true
> +  # C++ standard library includes (no extension)
> +  - Regex:           '<([A-Za-z0-9\-_/])+>'
> +    Priority:        3
> +  # Linux headers, as a second group/subset of system headers
> +  - Regex:           '<linux/.*>'
> +    Priority:        4
> +  # Headers for libcamera Base support
> +  - Regex:           '<libcamera/base/private.h>'
> +    Priority:        5
> +  - Regex:           '<libcamera/base/.*\.h>'
> +    Priority:        6
> +  # Public API Headers for libcamera, which are not in a subdir (i.e. ipa/,internal/)
> +  - Regex:           '<libcamera/([A-Za-z0-9\-_])+.h>'
> +    Priority:        7
> +  # IPA Interfaces
> +  - Regex:           '<libcamera/ipa/.*\.h>'
> +    Priority:        8
> +  # libcamera Internal headers in ""  
> +  - Regex:           '"libcamera/internal/.*\.h"'
> +    Priority:        9
> +  # Other libraries headers with one group per library (.h or .hpp)
> +  - Regex:           '<.*/.*\.hp*>'
> +    Priority:        10
> +  # local modular includes "path/file.h" (.h or .hpp)
> +  - Regex:           '"(.*/)+.*\.hp*"'
> +    Priority:        11
> +  # Other local headers "file.h" with extension (.h or .hpp)
> +  - Regex:           '".*.hp*"'
> +    Priority:        12
> +  # Any unmatched line, separated from the last group
> +  - Regex:	     '"*"'
> +    Priority:        100
> +
>  IncludeIsMainRegex: '(_test)?$'
>  IndentCaseLabels: false
>  IndentPPDirectives: None
> diff --git a/Documentation/coding-style.rst b/Documentation/coding-style.rst
> index 30c1778ed8bf..e4f1bb26024e 100644
> --- a/Documentation/coding-style.rst
> +++ b/Documentation/coding-style.rst
> @@ -70,19 +70,31 @@ macro. For .cpp files, if the file implements an API declared in a header file,
>  that header file shall be included first in order to ensure it is
>  self-contained.
>  
> +While the following list is extensive, it documents the expected behaviour
> +defined by the clang-format configuraiton and tooling should assist with
> +ordering.

s/configuraiton/configuration

Reviewed-by: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>

>  The headers shall be grouped and ordered as follows:
>  
>  1. The header declaring the API being implemented (if any)
> -2. The C and C++ system and standard library headers
> -3. Other libraries' headers, with one group per library
> -4. Other project's headers
> +2. The C standard library and system headers
> +3. The C++ standard library headers
> +4. Linux kernel headers
> +5. The libcamera base private header if required
> +6. The libcamera base library headers
> +7. The libcamera public API headers
> +8. The libcamera IPA interfaces
> +9. The internal libcamera headers
> +10. Other libraries' headers, with one group per library
> +11. Local headers grouped by subdirectory
> +12. Any local headers
>  
>  Groups of headers shall be separated by a single blank line. Headers within
>  each group shall be sorted alphabetically.
>  
>  System and library headers shall be included with angle brackets. Project
>  headers shall be included with angle brackets for the libcamera public API
> -headers, and with double quotes for other libcamera headers.
> +headers, and with double quotes for internal libcamera headers.
>  
>  
>  C++ Specific Rules
>
Laurent Pinchart Aug. 9, 2021, 4:36 p.m. UTC | #2
Hi Kieran,

Thank you for the patch.

On Mon, Aug 09, 2021 at 05:14:25PM +0100, Kieran Bingham wrote:
> Utilise the clang-format header sort to provide a regex based pattern
> match for our header inclusion coding style.
> 
> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
> ---
> A sample of all headers from the project (+ a couple of extra tests)
> parsed through this can be seen at 
>    https://paste.ubuntu.com/p/Bt87C6M77y/

There are a few headers there such as a.h and b.h that don't seem to
exist in libcamera. Did you run the commands below on a test branch by
any chance ?

> This was generated by:
>  git grep -h "^#include" | sort | uniq  > all-headers.cpp
>  git add all-headers.cpp
>  git commit all-headers.cpp -m "Header Test"
>  ./utils/checkstyle.py | patch -p0
> 
> While some false positives are visible in this list
>  (for instance <camera_metadata_hidden.h> in c/system headers section)
> this provides a great deal of the checks automatically, and the
> remaining cases may have to be spotted during review.

There's also

#include <jpeglib.h>
#include <libudev.h>
#include <tiffio.h>
#include <xf86drm.h>
#include <xf86drmMode.h>
#include <yaml.h>

in the system headers. I wonder if we should add a rule for those.

I've also spotted

#include "linux/bcm2835-isp.h"

that should be replaced with

#include <linux/bcm2835-isp.h>

>  .clang-format                  | 49 +++++++++++++++++++++++++++++++---
>  Documentation/coding-style.rst | 20 +++++++++++---
>  2 files changed, 62 insertions(+), 7 deletions(-)
> 
> diff --git a/.clang-format b/.clang-format
> index 3a8a896e373d..56cfbfa1bec4 100644
> --- a/.clang-format
> +++ b/.clang-format
> @@ -66,10 +66,53 @@ ExperimentalAutoDetectBinPacking: false
>  FixNamespaceComments: true
>  ForEachMacros:
>    - 'udev_list_entry_foreach'
> -IncludeBlocks: Preserve
> +SortIncludes: true
> +IncludeBlocks: Regroup
>  IncludeCategories:
> -  - Regex: '.*'
> -    Priority: 1
> +  # Headers matching the name of the component are matched automatically.
> +  # Priority 1
> +  # Headers in <> with an extension. (+system libraries)
> +  - Regex:           '<([A-Za-z0-9\-_])+\.h>'
> +    Priority:        2 
> +  - Regex:           '<sys/.*>'
> +    Priority:        2
> +  # Qt includes (match before C++ standard library)
> +  - Regex:           '<Q([A-Za-z0-9\-_])+>'
> +    Priority:        10
> +    CaseSensitive:   true
> +  # C++ standard library includes (no extension)
> +  - Regex:           '<([A-Za-z0-9\-_/])+>'
> +    Priority:        3
> +  # Linux headers, as a second group/subset of system headers
> +  - Regex:           '<linux/.*>'
> +    Priority:        4
> +  # Headers for libcamera Base support
> +  - Regex:           '<libcamera/base/private.h>'
> +    Priority:        5
> +  - Regex:           '<libcamera/base/.*\.h>'
> +    Priority:        6
> +  # Public API Headers for libcamera, which are not in a subdir (i.e. ipa/,internal/)
> +  - Regex:           '<libcamera/([A-Za-z0-9\-_])+.h>'
> +    Priority:        7
> +  # IPA Interfaces
> +  - Regex:           '<libcamera/ipa/.*\.h>'
> +    Priority:        8
> +  # libcamera Internal headers in ""  
> +  - Regex:           '"libcamera/internal/.*\.h"'
> +    Priority:        9
> +  # Other libraries headers with one group per library (.h or .hpp)
> +  - Regex:           '<.*/.*\.hp*>'
> +    Priority:        10
> +  # local modular includes "path/file.h" (.h or .hpp)
> +  - Regex:           '"(.*/)+.*\.hp*"'
> +    Priority:        11
> +  # Other local headers "file.h" with extension (.h or .hpp)
> +  - Regex:           '".*.hp*"'
> +    Priority:        12
> +  # Any unmatched line, separated from the last group
> +  - Regex:	     '"*"'
> +    Priority:        100
> +
>  IncludeIsMainRegex: '(_test)?$'
>  IndentCaseLabels: false
>  IndentPPDirectives: None
> diff --git a/Documentation/coding-style.rst b/Documentation/coding-style.rst
> index 30c1778ed8bf..e4f1bb26024e 100644
> --- a/Documentation/coding-style.rst
> +++ b/Documentation/coding-style.rst
> @@ -70,19 +70,31 @@ macro. For .cpp files, if the file implements an API declared in a header file,
>  that header file shall be included first in order to ensure it is
>  self-contained.
>  
> +While the following list is extensive, it documents the expected behaviour
> +defined by the clang-format configuraiton and tooling should assist with
> +ordering.
> +
>  The headers shall be grouped and ordered as follows:
>  
>  1. The header declaring the API being implemented (if any)
> -2. The C and C++ system and standard library headers
> -3. Other libraries' headers, with one group per library
> -4. Other project's headers
> +2. The C standard library and system headers
> +3. The C++ standard library headers

What's the rationale for splitting the C and C++ headers ?

> +4. Linux kernel headers
> +5. The libcamera base private header if required
> +6. The libcamera base library headers
> +7. The libcamera public API headers
> +8. The libcamera IPA interfaces
> +9. The internal libcamera headers
> +10. Other libraries' headers, with one group per library
> +11. Local headers grouped by subdirectory
> +12. Any local headers

There are substantial changes here, does this fix the documentation to
match what we actually do already, or does it change the current
practice ?

>  Groups of headers shall be separated by a single blank line. Headers within
>  each group shall be sorted alphabetically.
>  
>  System and library headers shall be included with angle brackets. Project
>  headers shall be included with angle brackets for the libcamera public API
> -headers, and with double quotes for other libcamera headers.
> +headers, and with double quotes for internal libcamera headers.
>  
>  
>  C++ Specific Rules
Kieran Bingham Aug. 9, 2021, 5:05 p.m. UTC | #3
Hi Laurent,

On 09/08/2021 17:36, Laurent Pinchart wrote:
> Hi Kieran,
> 
> Thank you for the patch.
> 
> On Mon, Aug 09, 2021 at 05:14:25PM +0100, Kieran Bingham wrote:
>> Utilise the clang-format header sort to provide a regex based pattern
>> match for our header inclusion coding style.
>>
>> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
>> ---
>> A sample of all headers from the project (+ a couple of extra tests)
>> parsed through this can be seen at 
>>    https://paste.ubuntu.com/p/Bt87C6M77y/
> 
> There are a few headers there such as a.h and b.h that don't seem to
> exist in libcamera. Did you run the commands below on a test branch by
> any chance ?

Intentionally, yes as stated in the three lines above your query " (+ a
couple of extra tests)"


> 
>> This was generated by:
>>  git grep -h "^#include" | sort | uniq  > all-headers.cpp
>>  git add all-headers.cpp
>>  git commit all-headers.cpp -m "Header Test"
>>  ./utils/checkstyle.py | patch -p0
>>
>> While some false positives are visible in this list
>>  (for instance <camera_metadata_hidden.h> in c/system headers section)
>> this provides a great deal of the checks automatically, and the
>> remaining cases may have to be spotted during review.
> 
> There's also
> 
> #include <jpeglib.h>
> #include <libudev.h>
> #include <tiffio.h>
> #include <xf86drm.h>
> #include <xf86drmMode.h>
> #include <yaml.h>
> 
> in the system headers. I wonder if we should add a rule for those.

We would have to add that set explicitly. That doesn't seem to scale, as
there would likely always be some extra files we'd have to add, and I
don't think we should be maintaining a list of 'all files' in a regex.

As you'll see, I've added an exception rule for the QT headers, as it
can match generically to prevent QT headers ending up in the C++ subset.


> I've also spotted
> 
> #include "linux/bcm2835-isp.h"
> 
> that should be replaced with
> 
> #include <linux/bcm2835-isp.h>


Sure - but that's a separate patch ;-) now sent.


>>  .clang-format                  | 49 +++++++++++++++++++++++++++++++---
>>  Documentation/coding-style.rst | 20 +++++++++++---
>>  2 files changed, 62 insertions(+), 7 deletions(-)
>>
>> diff --git a/.clang-format b/.clang-format
>> index 3a8a896e373d..56cfbfa1bec4 100644
>> --- a/.clang-format
>> +++ b/.clang-format
>> @@ -66,10 +66,53 @@ ExperimentalAutoDetectBinPacking: false
>>  FixNamespaceComments: true
>>  ForEachMacros:
>>    - 'udev_list_entry_foreach'
>> -IncludeBlocks: Preserve
>> +SortIncludes: true
>> +IncludeBlocks: Regroup
>>  IncludeCategories:
>> -  - Regex: '.*'
>> -    Priority: 1
>> +  # Headers matching the name of the component are matched automatically.
>> +  # Priority 1
>> +  # Headers in <> with an extension. (+system libraries)
>> +  - Regex:           '<([A-Za-z0-9\-_])+\.h>'
>> +    Priority:        2 
>> +  - Regex:           '<sys/.*>'
>> +    Priority:        2
>> +  # Qt includes (match before C++ standard library)
>> +  - Regex:           '<Q([A-Za-z0-9\-_])+>'
>> +    Priority:        10
>> +    CaseSensitive:   true
>> +  # C++ standard library includes (no extension)
>> +  - Regex:           '<([A-Za-z0-9\-_/])+>'
>> +    Priority:        3
>> +  # Linux headers, as a second group/subset of system headers
>> +  - Regex:           '<linux/.*>'
>> +    Priority:        4
>> +  # Headers for libcamera Base support
>> +  - Regex:           '<libcamera/base/private.h>'
>> +    Priority:        5
>> +  - Regex:           '<libcamera/base/.*\.h>'
>> +    Priority:        6
>> +  # Public API Headers for libcamera, which are not in a subdir (i.e. ipa/,internal/)
>> +  - Regex:           '<libcamera/([A-Za-z0-9\-_])+.h>'
>> +    Priority:        7
>> +  # IPA Interfaces
>> +  - Regex:           '<libcamera/ipa/.*\.h>'
>> +    Priority:        8
>> +  # libcamera Internal headers in ""  
>> +  - Regex:           '"libcamera/internal/.*\.h"'
>> +    Priority:        9
>> +  # Other libraries headers with one group per library (.h or .hpp)
>> +  - Regex:           '<.*/.*\.hp*>'
>> +    Priority:        10
>> +  # local modular includes "path/file.h" (.h or .hpp)
>> +  - Regex:           '"(.*/)+.*\.hp*"'
>> +    Priority:        11
>> +  # Other local headers "file.h" with extension (.h or .hpp)
>> +  - Regex:           '".*.hp*"'
>> +    Priority:        12
>> +  # Any unmatched line, separated from the last group
>> +  - Regex:	     '"*"'
>> +    Priority:        100
>> +
>>  IncludeIsMainRegex: '(_test)?$'
>>  IndentCaseLabels: false
>>  IndentPPDirectives: None
>> diff --git a/Documentation/coding-style.rst b/Documentation/coding-style.rst
>> index 30c1778ed8bf..e4f1bb26024e 100644
>> --- a/Documentation/coding-style.rst
>> +++ b/Documentation/coding-style.rst
>> @@ -70,19 +70,31 @@ macro. For .cpp files, if the file implements an API declared in a header file,
>>  that header file shall be included first in order to ensure it is
>>  self-contained.
>>  
>> +While the following list is extensive, it documents the expected behaviour
>> +defined by the clang-format configuraiton and tooling should assist with
>> +ordering.
>> +
>>  The headers shall be grouped and ordered as follows:
>>  
>>  1. The header declaring the API being implemented (if any)
>> -2. The C and C++ system and standard library headers
>> -3. Other libraries' headers, with one group per library
>> -4. Other project's headers
>> +2. The C standard library and system headers
>> +3. The C++ standard library headers
> 
> What's the rationale for splitting the C and C++ headers ?

At the moment just matching them. Though I thought we did so already
somewhere... but I can't find any examples of that, but there are plenty
of examples of them mixed, so I will re-join groups 2 and 3.


>> +4. Linux kernel headers
>> +5. The libcamera base private header if required
>> +6. The libcamera base library headers
>> +7. The libcamera public API headers
>> +8. The libcamera IPA interfaces
>> +9. The internal libcamera headers
>> +10. Other libraries' headers, with one group per library
>> +11. Local headers grouped by subdirectory
>> +12. Any local headers
> 
> There are substantial changes here, does this fix the documentation to
> match what we actually do already, or does it change the current
> practice ?

It aims to better match what current expected practice is ... at least
how I see it ...

Specifically - the base interfaces are all described like that in the
implementation, because I used a variant of this .clang-format to help
automate that split work.

There are lots of rules in the headers already (like
libcamera/base/private.h should be in it's own group, before the other
base headers) which this patch codifies.

There are many times where it's not easily obvious where an include
should go. This tries to specify that for the readers, and ... make it
so they don't have to look it up anyway, as the tooling will organise it
anyway.



>>  Groups of headers shall be separated by a single blank line. Headers within
>>  each group shall be sorted alphabetically.
>>  
>>  System and library headers shall be included with angle brackets. Project
>>  headers shall be included with angle brackets for the libcamera public API
>> -headers, and with double quotes for other libcamera headers.
>> +headers, and with double quotes for internal libcamera headers.
>>  
>>  
>>  C++ Specific Rules
>
Laurent Pinchart Aug. 9, 2021, 5:09 p.m. UTC | #4
Hi Kieran,

On Mon, Aug 09, 2021 at 06:05:36PM +0100, Kieran Bingham wrote:
> On 09/08/2021 17:36, Laurent Pinchart wrote:
> > On Mon, Aug 09, 2021 at 05:14:25PM +0100, Kieran Bingham wrote:
> >> Utilise the clang-format header sort to provide a regex based pattern
> >> match for our header inclusion coding style.
> >>
> >> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
> >> ---
> >> A sample of all headers from the project (+ a couple of extra tests)
> >> parsed through this can be seen at 
> >>    https://paste.ubuntu.com/p/Bt87C6M77y/
> > 
> > There are a few headers there such as a.h and b.h that don't seem to
> > exist in libcamera. Did you run the commands below on a test branch by
> > any chance ?
> 
> Intentionally, yes as stated in the three lines above your query " (+ a
> couple of extra tests)"

Oops indeed.

> >> This was generated by:
> >>  git grep -h "^#include" | sort | uniq  > all-headers.cpp
> >>  git add all-headers.cpp
> >>  git commit all-headers.cpp -m "Header Test"
> >>  ./utils/checkstyle.py | patch -p0
> >>
> >> While some false positives are visible in this list
> >>  (for instance <camera_metadata_hidden.h> in c/system headers section)
> >> this provides a great deal of the checks automatically, and the
> >> remaining cases may have to be spotted during review.
> > 
> > There's also
> > 
> > #include <jpeglib.h>
> > #include <libudev.h>
> > #include <tiffio.h>
> > #include <xf86drm.h>
> > #include <xf86drmMode.h>
> > #include <yaml.h>
> > 
> > in the system headers. I wonder if we should add a rule for those.
> 
> We would have to add that set explicitly. That doesn't seem to scale, as
> there would likely always be some extra files we'd have to add, and I
> don't think we should be maintaining a list of 'all files' in a regex.

As we have few external dependencies I thought this list may change
infrequently enough that it could be maintainable (especially
considering that most external dependencies will have a directory name
as a prefix), but I also understand the opposite argument.

> As you'll see, I've added an exception rule for the QT headers, as it
> can match generically to prevent QT headers ending up in the C++ subset.
> 
> > I've also spotted
> > 
> > #include "linux/bcm2835-isp.h"
> > 
> > that should be replaced with
> > 
> > #include <linux/bcm2835-isp.h>
> 
> Sure - but that's a separate patch ;-) now sent.

Thanks.

> >>  .clang-format                  | 49 +++++++++++++++++++++++++++++++---
> >>  Documentation/coding-style.rst | 20 +++++++++++---
> >>  2 files changed, 62 insertions(+), 7 deletions(-)
> >>
> >> diff --git a/.clang-format b/.clang-format
> >> index 3a8a896e373d..56cfbfa1bec4 100644
> >> --- a/.clang-format
> >> +++ b/.clang-format
> >> @@ -66,10 +66,53 @@ ExperimentalAutoDetectBinPacking: false
> >>  FixNamespaceComments: true
> >>  ForEachMacros:
> >>    - 'udev_list_entry_foreach'
> >> -IncludeBlocks: Preserve
> >> +SortIncludes: true
> >> +IncludeBlocks: Regroup
> >>  IncludeCategories:
> >> -  - Regex: '.*'
> >> -    Priority: 1
> >> +  # Headers matching the name of the component are matched automatically.
> >> +  # Priority 1
> >> +  # Headers in <> with an extension. (+system libraries)
> >> +  - Regex:           '<([A-Za-z0-9\-_])+\.h>'
> >> +    Priority:        2 
> >> +  - Regex:           '<sys/.*>'
> >> +    Priority:        2
> >> +  # Qt includes (match before C++ standard library)
> >> +  - Regex:           '<Q([A-Za-z0-9\-_])+>'
> >> +    Priority:        10
> >> +    CaseSensitive:   true
> >> +  # C++ standard library includes (no extension)
> >> +  - Regex:           '<([A-Za-z0-9\-_/])+>'
> >> +    Priority:        3
> >> +  # Linux headers, as a second group/subset of system headers
> >> +  - Regex:           '<linux/.*>'
> >> +    Priority:        4
> >> +  # Headers for libcamera Base support
> >> +  - Regex:           '<libcamera/base/private.h>'
> >> +    Priority:        5
> >> +  - Regex:           '<libcamera/base/.*\.h>'
> >> +    Priority:        6
> >> +  # Public API Headers for libcamera, which are not in a subdir (i.e. ipa/,internal/)
> >> +  - Regex:           '<libcamera/([A-Za-z0-9\-_])+.h>'
> >> +    Priority:        7
> >> +  # IPA Interfaces
> >> +  - Regex:           '<libcamera/ipa/.*\.h>'
> >> +    Priority:        8
> >> +  # libcamera Internal headers in ""  
> >> +  - Regex:           '"libcamera/internal/.*\.h"'
> >> +    Priority:        9
> >> +  # Other libraries headers with one group per library (.h or .hpp)
> >> +  - Regex:           '<.*/.*\.hp*>'
> >> +    Priority:        10
> >> +  # local modular includes "path/file.h" (.h or .hpp)
> >> +  - Regex:           '"(.*/)+.*\.hp*"'
> >> +    Priority:        11
> >> +  # Other local headers "file.h" with extension (.h or .hpp)
> >> +  - Regex:           '".*.hp*"'
> >> +    Priority:        12
> >> +  # Any unmatched line, separated from the last group
> >> +  - Regex:	     '"*"'
> >> +    Priority:        100
> >> +
> >>  IncludeIsMainRegex: '(_test)?$'
> >>  IndentCaseLabels: false
> >>  IndentPPDirectives: None
> >> diff --git a/Documentation/coding-style.rst b/Documentation/coding-style.rst
> >> index 30c1778ed8bf..e4f1bb26024e 100644
> >> --- a/Documentation/coding-style.rst
> >> +++ b/Documentation/coding-style.rst
> >> @@ -70,19 +70,31 @@ macro. For .cpp files, if the file implements an API declared in a header file,
> >>  that header file shall be included first in order to ensure it is
> >>  self-contained.
> >>  
> >> +While the following list is extensive, it documents the expected behaviour
> >> +defined by the clang-format configuraiton and tooling should assist with
> >> +ordering.
> >> +
> >>  The headers shall be grouped and ordered as follows:
> >>  
> >>  1. The header declaring the API being implemented (if any)
> >> -2. The C and C++ system and standard library headers
> >> -3. Other libraries' headers, with one group per library
> >> -4. Other project's headers
> >> +2. The C standard library and system headers
> >> +3. The C++ standard library headers
> > 
> > What's the rationale for splitting the C and C++ headers ?
> 
> At the moment just matching them. Though I thought we did so already
> somewhere... but I can't find any examples of that, but there are plenty
> of examples of them mixed, so I will re-join groups 2 and 3.

Ack.

> >> +4. Linux kernel headers
> >> +5. The libcamera base private header if required
> >> +6. The libcamera base library headers
> >> +7. The libcamera public API headers
> >> +8. The libcamera IPA interfaces
> >> +9. The internal libcamera headers
> >> +10. Other libraries' headers, with one group per library
> >> +11. Local headers grouped by subdirectory
> >> +12. Any local headers
> > 
> > There are substantial changes here, does this fix the documentation to
> > match what we actually do already, or does it change the current
> > practice ?
> 
> It aims to better match what current expected practice is ... at least
> how I see it ...
> 
> Specifically - the base interfaces are all described like that in the
> implementation, because I used a variant of this .clang-format to help
> automate that split work.
> 
> There are lots of rules in the headers already (like
> libcamera/base/private.h should be in it's own group, before the other
> base headers) which this patch codifies.
> 
> There are many times where it's not easily obvious where an include
> should go. This tries to specify that for the readers, and ... make it
> so they don't have to look it up anyway, as the tooling will organise it
> anyway.

Fine with me. Could you mention in the commit message that the rules are
created to match the existing practices, and that the documentation is
updated accordingly ? With that,

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> >>  Groups of headers shall be separated by a single blank line. Headers within
> >>  each group shall be sorted alphabetically.
> >>  
> >>  System and library headers shall be included with angle brackets. Project
> >>  headers shall be included with angle brackets for the libcamera public API
> >> -headers, and with double quotes for other libcamera headers.
> >> +headers, and with double quotes for internal libcamera headers.
> >>  
> >>  
> >>  C++ Specific Rules
Kieran Bingham Aug. 9, 2021, 5:13 p.m. UTC | #5
Hi Laurent,

On 09/08/2021 18:09, Laurent Pinchart wrote:
> Hi Kieran,
> 
> On Mon, Aug 09, 2021 at 06:05:36PM +0100, Kieran Bingham wrote:
>> On 09/08/2021 17:36, Laurent Pinchart wrote:
>>> On Mon, Aug 09, 2021 at 05:14:25PM +0100, Kieran Bingham wrote:
>>>> Utilise the clang-format header sort to provide a regex based pattern
>>>> match for our header inclusion coding style.
>>>>
>>>> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
>>>> ---
>>>> A sample of all headers from the project (+ a couple of extra tests)
>>>> parsed through this can be seen at 
>>>>    https://paste.ubuntu.com/p/Bt87C6M77y/
>>>
>>> There are a few headers there such as a.h and b.h that don't seem to
>>> exist in libcamera. Did you run the commands below on a test branch by
>>> any chance ?
>>
>> Intentionally, yes as stated in the three lines above your query " (+ a
>> couple of extra tests)"
> 
> Oops indeed.
> 
>>>> This was generated by:
>>>>  git grep -h "^#include" | sort | uniq  > all-headers.cpp
>>>>  git add all-headers.cpp
>>>>  git commit all-headers.cpp -m "Header Test"
>>>>  ./utils/checkstyle.py | patch -p0
>>>>
>>>> While some false positives are visible in this list
>>>>  (for instance <camera_metadata_hidden.h> in c/system headers section)
>>>> this provides a great deal of the checks automatically, and the
>>>> remaining cases may have to be spotted during review.
>>>
>>> There's also
>>>
>>> #include <jpeglib.h>
>>> #include <libudev.h>
>>> #include <tiffio.h>
>>> #include <xf86drm.h>
>>> #include <xf86drmMode.h>
>>> #include <yaml.h>
>>>
>>> in the system headers. I wonder if we should add a rule for those.
>>
>> We would have to add that set explicitly. That doesn't seem to scale, as
>> there would likely always be some extra files we'd have to add, and I
>> don't think we should be maintaining a list of 'all files' in a regex.
> 
> As we have few external dependencies I thought this list may change
> infrequently enough that it could be maintainable (especially
> considering that most external dependencies will have a directory name
> as a prefix), but I also understand the opposite argument.

Indeed, dependencies with a directory name are better, as they already
get matched to group 10 (9, now that I've merged C and C++).



>> As you'll see, I've added an exception rule for the QT headers, as it
>> can match generically to prevent QT headers ending up in the C++ subset.
>>
>>> I've also spotted
>>>
>>> #include "linux/bcm2835-isp.h"
>>>
>>> that should be replaced with
>>>
>>> #include <linux/bcm2835-isp.h>
>>
>> Sure - but that's a separate patch ;-) now sent.
> 
> Thanks.
> 
>>>>  .clang-format                  | 49 +++++++++++++++++++++++++++++++---
>>>>  Documentation/coding-style.rst | 20 +++++++++++---
>>>>  2 files changed, 62 insertions(+), 7 deletions(-)
>>>>
>>>> diff --git a/.clang-format b/.clang-format
>>>> index 3a8a896e373d..56cfbfa1bec4 100644
>>>> --- a/.clang-format
>>>> +++ b/.clang-format
>>>> @@ -66,10 +66,53 @@ ExperimentalAutoDetectBinPacking: false
>>>>  FixNamespaceComments: true
>>>>  ForEachMacros:
>>>>    - 'udev_list_entry_foreach'
>>>> -IncludeBlocks: Preserve
>>>> +SortIncludes: true
>>>> +IncludeBlocks: Regroup
>>>>  IncludeCategories:
>>>> -  - Regex: '.*'
>>>> -    Priority: 1
>>>> +  # Headers matching the name of the component are matched automatically.
>>>> +  # Priority 1
>>>> +  # Headers in <> with an extension. (+system libraries)
>>>> +  - Regex:           '<([A-Za-z0-9\-_])+\.h>'
>>>> +    Priority:        2 
>>>> +  - Regex:           '<sys/.*>'
>>>> +    Priority:        2
>>>> +  # Qt includes (match before C++ standard library)
>>>> +  - Regex:           '<Q([A-Za-z0-9\-_])+>'
>>>> +    Priority:        10
>>>> +    CaseSensitive:   true
>>>> +  # C++ standard library includes (no extension)
>>>> +  - Regex:           '<([A-Za-z0-9\-_/])+>'
>>>> +    Priority:        3
>>>> +  # Linux headers, as a second group/subset of system headers
>>>> +  - Regex:           '<linux/.*>'
>>>> +    Priority:        4
>>>> +  # Headers for libcamera Base support
>>>> +  - Regex:           '<libcamera/base/private.h>'
>>>> +    Priority:        5
>>>> +  - Regex:           '<libcamera/base/.*\.h>'
>>>> +    Priority:        6
>>>> +  # Public API Headers for libcamera, which are not in a subdir (i.e. ipa/,internal/)
>>>> +  - Regex:           '<libcamera/([A-Za-z0-9\-_])+.h>'
>>>> +    Priority:        7
>>>> +  # IPA Interfaces
>>>> +  - Regex:           '<libcamera/ipa/.*\.h>'
>>>> +    Priority:        8
>>>> +  # libcamera Internal headers in ""  
>>>> +  - Regex:           '"libcamera/internal/.*\.h"'
>>>> +    Priority:        9
>>>> +  # Other libraries headers with one group per library (.h or .hpp)
>>>> +  - Regex:           '<.*/.*\.hp*>'
>>>> +    Priority:        10
>>>> +  # local modular includes "path/file.h" (.h or .hpp)
>>>> +  - Regex:           '"(.*/)+.*\.hp*"'
>>>> +    Priority:        11
>>>> +  # Other local headers "file.h" with extension (.h or .hpp)
>>>> +  - Regex:           '".*.hp*"'
>>>> +    Priority:        12
>>>> +  # Any unmatched line, separated from the last group
>>>> +  - Regex:	     '"*"'
>>>> +    Priority:        100
>>>> +
>>>>  IncludeIsMainRegex: '(_test)?$'
>>>>  IndentCaseLabels: false
>>>>  IndentPPDirectives: None
>>>> diff --git a/Documentation/coding-style.rst b/Documentation/coding-style.rst
>>>> index 30c1778ed8bf..e4f1bb26024e 100644
>>>> --- a/Documentation/coding-style.rst
>>>> +++ b/Documentation/coding-style.rst
>>>> @@ -70,19 +70,31 @@ macro. For .cpp files, if the file implements an API declared in a header file,
>>>>  that header file shall be included first in order to ensure it is
>>>>  self-contained.
>>>>  
>>>> +While the following list is extensive, it documents the expected behaviour
>>>> +defined by the clang-format configuraiton and tooling should assist with
>>>> +ordering.
>>>> +
>>>>  The headers shall be grouped and ordered as follows:
>>>>  
>>>>  1. The header declaring the API being implemented (if any)
>>>> -2. The C and C++ system and standard library headers
>>>> -3. Other libraries' headers, with one group per library
>>>> -4. Other project's headers
>>>> +2. The C standard library and system headers
>>>> +3. The C++ standard library headers
>>>
>>> What's the rationale for splitting the C and C++ headers ?
>>
>> At the moment just matching them. Though I thought we did so already
>> somewhere... but I can't find any examples of that, but there are plenty
>> of examples of them mixed, so I will re-join groups 2 and 3.
> 
> Ack.

Done, but somehow in the big merged list - it looks ugly ;-)

I liked seeing them split.


> 
>>>> +4. Linux kernel headers
>>>> +5. The libcamera base private header if required
>>>> +6. The libcamera base library headers
>>>> +7. The libcamera public API headers
>>>> +8. The libcamera IPA interfaces
>>>> +9. The internal libcamera headers
>>>> +10. Other libraries' headers, with one group per library
>>>> +11. Local headers grouped by subdirectory
>>>> +12. Any local headers
>>>
>>> There are substantial changes here, does this fix the documentation to
>>> match what we actually do already, or does it change the current
>>> practice ?
>>
>> It aims to better match what current expected practice is ... at least
>> how I see it ...
>>
>> Specifically - the base interfaces are all described like that in the
>> implementation, because I used a variant of this .clang-format to help
>> automate that split work.
>>
>> There are lots of rules in the headers already (like
>> libcamera/base/private.h should be in it's own group, before the other
>> base headers) which this patch codifies.
>>
>> There are many times where it's not easily obvious where an include
>> should go. This tries to specify that for the readers, and ... make it
>> so they don't have to look it up anyway, as the tooling will organise it
>> anyway.
> 
> Fine with me. Could you mention in the commit message that the rules are
> created to match the existing practices, and that the documentation is
> updated accordingly ? With that,

Sure.

Thanks.



> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> 
>>>>  Groups of headers shall be separated by a single blank line. Headers within
>>>>  each group shall be sorted alphabetically.
>>>>  
>>>>  System and library headers shall be included with angle brackets. Project
>>>>  headers shall be included with angle brackets for the libcamera public API
>>>> -headers, and with double quotes for other libcamera headers.
>>>> +headers, and with double quotes for internal libcamera headers.
>>>>  
>>>>  
>>>>  C++ Specific Rules
>

Patch
diff mbox series

diff --git a/.clang-format b/.clang-format
index 3a8a896e373d..56cfbfa1bec4 100644
--- a/.clang-format
+++ b/.clang-format
@@ -66,10 +66,53 @@  ExperimentalAutoDetectBinPacking: false
 FixNamespaceComments: true
 ForEachMacros:
   - 'udev_list_entry_foreach'
-IncludeBlocks: Preserve
+SortIncludes: true
+IncludeBlocks: Regroup
 IncludeCategories:
-  - Regex: '.*'
-    Priority: 1
+  # Headers matching the name of the component are matched automatically.
+  # Priority 1
+  # Headers in <> with an extension. (+system libraries)
+  - Regex:           '<([A-Za-z0-9\-_])+\.h>'
+    Priority:        2 
+  - Regex:           '<sys/.*>'
+    Priority:        2
+  # Qt includes (match before C++ standard library)
+  - Regex:           '<Q([A-Za-z0-9\-_])+>'
+    Priority:        10
+    CaseSensitive:   true
+  # C++ standard library includes (no extension)
+  - Regex:           '<([A-Za-z0-9\-_/])+>'
+    Priority:        3
+  # Linux headers, as a second group/subset of system headers
+  - Regex:           '<linux/.*>'
+    Priority:        4
+  # Headers for libcamera Base support
+  - Regex:           '<libcamera/base/private.h>'
+    Priority:        5
+  - Regex:           '<libcamera/base/.*\.h>'
+    Priority:        6
+  # Public API Headers for libcamera, which are not in a subdir (i.e. ipa/,internal/)
+  - Regex:           '<libcamera/([A-Za-z0-9\-_])+.h>'
+    Priority:        7
+  # IPA Interfaces
+  - Regex:           '<libcamera/ipa/.*\.h>'
+    Priority:        8
+  # libcamera Internal headers in ""  
+  - Regex:           '"libcamera/internal/.*\.h"'
+    Priority:        9
+  # Other libraries headers with one group per library (.h or .hpp)
+  - Regex:           '<.*/.*\.hp*>'
+    Priority:        10
+  # local modular includes "path/file.h" (.h or .hpp)
+  - Regex:           '"(.*/)+.*\.hp*"'
+    Priority:        11
+  # Other local headers "file.h" with extension (.h or .hpp)
+  - Regex:           '".*.hp*"'
+    Priority:        12
+  # Any unmatched line, separated from the last group
+  - Regex:	     '"*"'
+    Priority:        100
+
 IncludeIsMainRegex: '(_test)?$'
 IndentCaseLabels: false
 IndentPPDirectives: None
diff --git a/Documentation/coding-style.rst b/Documentation/coding-style.rst
index 30c1778ed8bf..e4f1bb26024e 100644
--- a/Documentation/coding-style.rst
+++ b/Documentation/coding-style.rst
@@ -70,19 +70,31 @@  macro. For .cpp files, if the file implements an API declared in a header file,
 that header file shall be included first in order to ensure it is
 self-contained.
 
+While the following list is extensive, it documents the expected behaviour
+defined by the clang-format configuraiton and tooling should assist with
+ordering.
+
 The headers shall be grouped and ordered as follows:
 
 1. The header declaring the API being implemented (if any)
-2. The C and C++ system and standard library headers
-3. Other libraries' headers, with one group per library
-4. Other project's headers
+2. The C standard library and system headers
+3. The C++ standard library headers
+4. Linux kernel headers
+5. The libcamera base private header if required
+6. The libcamera base library headers
+7. The libcamera public API headers
+8. The libcamera IPA interfaces
+9. The internal libcamera headers
+10. Other libraries' headers, with one group per library
+11. Local headers grouped by subdirectory
+12. Any local headers
 
 Groups of headers shall be separated by a single blank line. Headers within
 each group shall be sorted alphabetically.
 
 System and library headers shall be included with angle brackets. Project
 headers shall be included with angle brackets for the libcamera public API
-headers, and with double quotes for other libcamera headers.
+headers, and with double quotes for internal libcamera headers.
 
 
 C++ Specific Rules