* [PATCH v4 1/2] checkpatch: add verbose mode
2021-02-17 16:54 [PATCH v4 0/2] checkpatch: add verbose mode Dwaipayan Ray
@ 2021-02-17 16:54 ` Dwaipayan Ray
2021-02-19 17:55 ` Joe Perches
2021-02-17 16:54 ` [PATCH v4 2/2] docs: add documentation for checkpatch Dwaipayan Ray
1 sibling, 1 reply; 6+ messages in thread
From: Dwaipayan Ray @ 2021-02-17 16:54 UTC (permalink / raw)
To: joe; +Cc: lukas.bulwahn, linux-kernel-mentees, linux-kernel, Dwaipayan Ray
Add a new verbose mode to checkpatch.pl to emit additional verbose
test descriptions. The verbose mode is optional and can be enabled
by the flag -v or --verbose.
The test descriptions are parsed from the checkpatch documentation
file at `Documentation/dev-tools/checkpatch.rst`. The test
descriptions in the docs are kept in a fixed format grouped by
usage. Some examples of the descriptions are:
**LINE_SPACING**
Vertical space is wasted given the limited number of lines an
editor window can display when multiple blank lines are used.
**MISSING_SIGN_OFF**
The patch is missing a Signed-off-by line. A signed-off-by
line should be added according to Developer's certificate of
Origin.
ref: `Documentation/process/submitting-patches.rst`
The verbose descriptions are not shown when the --terse option
is enabled.
Signed-off-by: Dwaipayan Ray <dwaipayanray1@gmail.com>
---
scripts/checkpatch.pl | 61 ++++++++++++++++++++++++++++++++++++++++---
1 file changed, 58 insertions(+), 3 deletions(-)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 9a549b009d2f..eeec412610d8 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -23,6 +23,8 @@ my $V = '0.32';
use Getopt::Long qw(:config no_auto_abbrev);
my $quiet = 0;
+my $verbose = 0;
+my %verbose_messages = ();
my $tree = 1;
my $chk_signoff = 1;
my $chk_patch = 1;
@@ -61,6 +63,7 @@ my $spelling_file = "$D/spelling.txt";
my $codespell = 0;
my $codespellfile = "/usr/share/codespell/dictionary.txt";
my $conststructsfile = "$D/const_structs.checkpatch";
+my $docsfile = "$D/../Documentation/dev-tools/checkpatch.rst";
my $typedefsfile;
my $color = "auto";
my $allow_c99_comments = 1; # Can be overridden by --ignore C99_COMMENT_TOLERANCE
@@ -78,6 +81,7 @@ Version: $V
Options:
-q, --quiet quiet
+ -v, --verbose verbose mode
--no-tree run without a kernel tree
--no-signoff do not check for 'Signed-off-by' line
--patch treat FILE as patchfile (default)
@@ -198,6 +202,46 @@ if (-f $conf) {
unshift(@ARGV, @conf_args) if @conf_args;
}
+sub load_docs {
+ open(my $docs, '<', "$docsfile")
+ or warn "$P: Can't read the documentation file $docsfile $!\n";
+
+ my $type = '';
+ my $desc = '';
+ my $in_desc = 0;
+
+ while (<$docs>) {
+ chomp;
+ my $line = $_;
+ $line =~ s/\s+$//;
+
+ if ($line =~ /^\s*\*\*(.+)\*\*$/) {
+ if ($desc ne '') {
+ $verbose_messages{$type} = trim($desc);
+ }
+ $type = $1;
+ $desc = '';
+ $in_desc = 1;
+ } elsif ($in_desc) {
+ if ($line =~ /^(?:\s{4,}|$)/) {
+ $line =~ s/^\s{4}//;
+ $desc .= $line;
+ $desc .= "\n";
+ } else {
+ $verbose_messages{$type} = trim($desc);
+ $type = '';
+ $desc = '';
+ $in_desc = 0;
+ }
+ }
+ }
+
+ if ($desc ne '') {
+ $verbose_messages{$type} = trim($desc);
+ }
+ close($docs);
+}
+
# Perl's Getopt::Long allows options to take optional arguments after a space.
# Prevent --color by itself from consuming other arguments
foreach (@ARGV) {
@@ -208,6 +252,7 @@ foreach (@ARGV) {
GetOptions(
'q|quiet+' => \$quiet,
+ 'v|verbose!' => \$verbose,
'tree!' => \$tree,
'signoff!' => \$chk_signoff,
'patch!' => \$chk_patch,
@@ -247,13 +292,15 @@ GetOptions(
help(0) if ($help);
+die "$P: --git cannot be used with --file or --fix\n" if ($git && ($file || $fix));
+die "$P: --verbose cannot be used with --terse\n" if ($verbose && $terse);
+
list_types(0) if ($list_types);
+load_docs() if ($verbose);
$fix = 1 if ($fix_inplace);
$check_orig = $check;
-die "$P: --git cannot be used with --file or --fix\n" if ($git && ($file || $fix));
-
my $exit = 0;
my $perl_version_ok = 1;
@@ -2209,7 +2256,15 @@ sub report {
splice(@lines, 1, 1);
$output = join("\n", @lines);
}
- $output = (split('\n', $output))[0] . "\n" if ($terse);
+
+ if ($terse) {
+ $output = (split('\n', $output))[0] . "\n";
+ }
+
+ if ($verbose &&
+ exists $verbose_messages{$type}) {
+ $output .= $verbose_messages{$type} . "\n\n";
+ }
push(our @report, $output);
--
2.30.0
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v4 2/2] docs: add documentation for checkpatch
2021-02-17 16:54 [PATCH v4 0/2] checkpatch: add verbose mode Dwaipayan Ray
2021-02-17 16:54 ` [PATCH v4 1/2] " Dwaipayan Ray
@ 2021-02-17 16:54 ` Dwaipayan Ray
2021-02-19 17:55 ` Joe Perches
1 sibling, 1 reply; 6+ messages in thread
From: Dwaipayan Ray @ 2021-02-17 16:54 UTC (permalink / raw)
To: joe; +Cc: lukas.bulwahn, linux-kernel-mentees, linux-kernel, Dwaipayan Ray
Add documentation for kernel script checkpatch.pl.
This documentation is also parsed by checkpatch to
enable a verbose mode.
The checkpatch message types are grouped by usage. Under
each group the types are described briefly. 34 of such
types are documented.
Signed-off-by: Dwaipayan Ray <dwaipayanray1@gmail.com>
---
Documentation/dev-tools/checkpatch.rst | 525 +++++++++++++++++++++++++
Documentation/dev-tools/index.rst | 1 +
2 files changed, 526 insertions(+)
create mode 100644 Documentation/dev-tools/checkpatch.rst
diff --git a/Documentation/dev-tools/checkpatch.rst b/Documentation/dev-tools/checkpatch.rst
new file mode 100644
index 000000000000..93f5f21a7204
--- /dev/null
+++ b/Documentation/dev-tools/checkpatch.rst
@@ -0,0 +1,525 @@
+.. SPDX-License-Identifier: GPL-2.0-only
+
+==========
+Checkpatch
+==========
+
+This document describes the kernel script checkpatch.pl.
+
+.. Table of Contents
+
+ === Introduction
+ === Options
+ === Message Levels
+ === Type Descriptions
+
+Introduction
+============
+
+Checkpatch (scripts/checkpatch.pl) is a perl script which checks for trivial
+style violations in patches and optionally corrects them. Checkpatch can
+also be run on file contexts and without the kernel tree.
+
+Checkpatch is not always right. Your judgement takes precedence over checkpatch
+messages. If your code looks better with the violations, then its probably
+best left alone.
+
+
+Options
+=======
+
+This section will describe the options checkpatch can be run with.
+
+Usage::
+
+ ./scripts/checkpatch.pl [OPTION]... [FILE]...
+
+Available options:
+
+ - -q, --quiet
+
+ Enable quiet mode.
+
+ - -v, --verbose
+ Enable verbose mode. Additional verbose test descriptions are output
+ so as to provide information on why that particular message is shown.
+
+ - --no-tree
+
+ Run checkpatch without the kernel tree.
+
+ - --no-signoff
+
+ Disable the 'Signed-off-by' line check. The sign-off is a simple line at
+ the end of the explanation for the patch, which certifies that you wrote it
+ or otherwise have the right to pass it on as an open-source patch.
+
+ Example::
+
+ Signed-off-by: Random J Developer <random@developer.example.org>
+
+ Setting this flag effectively stops a message for a missing signed-off-by
+ line in a patch context.
+
+ - --patch
+
+ Treat FILE as a patch. This is the default option and need not be
+ explicitly specified.
+
+ - --emacs
+
+ Set output to emacs compile window format. This allows emacs users to jump
+ from the error in the compile window directly to the offending line in the
+ patch.
+
+ - --terse
+
+ Output only one line per report.
+
+ - --showfile
+
+ Show the diffed file position instead of the input file position.
+
+ - -g, --git
+
+ Treat FILE as a single commit or a git revision range.
+
+ Single commit with:
+
+ - <rev>
+ - <rev>^
+ - <rev>~n
+
+ Multiple commits with:
+
+ - <rev1>..<rev2>
+ - <rev1>...<rev2>
+ - <rev>-<count>
+
+ - -f, --file
+
+ Treat FILE as a regular source file. This option must be used when running
+ checkpatch on source files in the kernel.
+
+ - --subjective, --strict
+
+ Enable stricter tests in checkpatch. By default the tests emitted as CHECK
+ do not activate by default. Use this flag to activate the CHECK tests.
+
+ - --list-types
+
+ Every message emitted by checkpatch has an associated TYPE. Add this flag
+ to display all the types in checkpatch.
+
+ Note that when this flag is active, checkpatch does not read the input FILE,
+ and no message is emitted. Only a list of types in checkpatch is output.
+
+ - --types TYPE(,TYPE2...)
+
+ Only display messages with the given types.
+
+ Example::
+
+ ./scripts/checkpatch.pl mypatch.patch --types EMAIL_SUBJECT,BRACES
+
+ - --ignore TYPE(,TYPE2...)
+
+ Checkpatch will not emit messages for the specified types.
+
+ Example::
+
+ ./scripts/checkpatch.pl mypatch.patch --ignore EMAIL_SUBJECT,BRACES
+
+ - --show-types
+
+ By default checkpatch doesn't display the type associated with the messages.
+ Set this flag to show the message type in the output.
+
+ - --max-line-length=n
+
+ Set the max line length (default 100). If a line exceeds the specified
+ length, a LONG_LINE message is emitted.
+
+
+ The message level is different for patch and file contexts. For patches,
+ a WARNING is emitted. While a milder CHECK is emitted for files. So for
+ file contexts, the --strict flag must also be enabled.
+
+ - --min-conf-desc-length=n
+
+ Set the Kconfig entry minimum description length, if shorter, warn.
+
+ - --tab-size=n
+
+ Set the number of spaces for tab (default 8).
+
+ - --root=PATH
+
+ PATH to the kernel tree root.
+
+ This option must be specified when invoking checkpatch from outside
+ the kernel root.
+
+ - --no-summary
+
+ Suppress the per file summary.
+
+ - --mailback
+
+ Only produce a report in case of Warnings or Errors. Milder Checks are
+ excluded from this.
+
+ - --summary-file
+
+ Include the filename in summary.
+
+ - --debug KEY=[0|1]
+
+ Turn on/off debugging of KEY, where KEY is one of 'values', 'possible',
+ 'type', and 'attr' (default is all off).
+
+ - --fix
+
+ This is an EXPERIMENTAL feature. If correctable errors exists, a file
+ <inputfile>.EXPERIMENTAL-checkpatch-fixes is created which has the
+ automatically fixable errors corrected.
+
+ - --fix-inplace
+
+ EXPERIMENTAL - Similar to --fix but input file is overwritten with fixes.
+
+ DO NOT USE this flag unless you are absolutely sure and you have a backup
+ in place.
+
+ - --ignore-perl-version
+
+ Override checking of perl version. Runtime errors maybe encountered after
+ enabling this flag if the perl version does not meet the minimum specified.
+
+ - --codespell
+
+ Use the codespell dictionary for checking spelling errors.
+
+ - --codespellfile
+
+ Use the specified codespell file.
+ Default is '/usr/share/codespell/dictionary.txt'.
+
+ - --typedefsfile
+
+ Read additional types from this file.
+
+ - --color[=WHEN]
+
+ Use colors 'always', 'never', or only when output is a terminal ('auto').
+ Default is 'auto'.
+
+ - --kconfig-prefix=WORD
+
+ Use WORD as a prefix for Kconfig symbols (default is `CONFIG_`).
+
+ - -h, --help, --version
+
+ Display the help text.
+
+Message Levels
+==============
+
+Messages in checkpatch are divided into three levels. The levels of messages
+in checkpatch denote the severity of the error. They are:
+
+ - ERROR
+
+ This is the most strict level. Messages of type ERROR must be taken
+ seriously as they denote things that are very likely to be wrong.
+
+ - WARNING
+
+ This is the next stricter level. Messages of type WARNING requires a
+ more careful review. But it is milder than an ERROR.
+
+ - CHECK
+
+ This is the mildest level. These are things which may require some thought.
+
+Type Descriptions
+=================
+
+This section contains a description of all the message types in checkpatch.
+
+.. Types in this section are also parsed by checkpatch.
+.. The types are grouped into subsections based on use.
+
+
+Allocation style
+----------------
+
+ **ALLOC_ARRAY_ARGS**
+ The first argument for kcalloc or kmalloc_array should be the
+ number of elements. sizeof() as the first argument is generally
+ wrong.
+ Ref: `Documentation/core-api/memory-allocation.rst`
+
+ **ALLOC_SIZEOF_STRUCT**
+ The allocation style is bad. In general for family of
+ allocation functions using sizeof() to get memory size,
+ constructs like::
+
+ p = alloc(sizeof(struct foo), ...)
+
+ should be::
+
+ p = alloc(sizeof(*p), ...)
+
+ Ref: `Documentation/process/coding-style.rst section 14`
+
+ **ALLOC_WITH_MULTIPLY**
+ Prefer kmalloc_array/kcalloc over kmalloc/kzalloc with a
+ sizeof multiply.
+ Ref: `Documentation/core-api/memory-allocation.rst`
+
+
+API usage
+---------
+
+ **ARCH_DEFINES**
+ Architecture specific defines should be avoided wherever
+ possible.
+
+ **ARCH_INCLUDE_LINUX**
+ Whenever asm/file.h is included and linux/file.h exists, a
+ conversion can be made when linux/file.h includes asm/file.h.
+ However this is not always the case (See signal.h).
+ This message type is emitted only for includes from arch/.
+
+ **ARRAY_SIZE**
+ The ARRAY_SIZE(foo) macro should be preferred over
+ sizeof(foo)/sizeof(foo[0]) for finding number of elements in an
+ array.
+
+ The macro is defined in include/linux/kernel.h::
+
+ #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+
+ **AVOID_BUG**
+ BUG() or BUG_ON() should be avoided totally.
+ Use WARN() and WARN_ON() instead, and handle the "impossible"
+ error condition as gracefully as possible.
+ Ref: `Documentation/process/deprecated.rst`
+
+ **AVOID_EXTERNS**
+ Function prototypes don't need to be declared extern in .h
+ files. It's assumed by the compiler and is unnecessary.
+
+ **AVOID_L_PREFIX**
+ Local symbol names that are prefixed with `.L` should be avoided,
+ as this has special meaning for the assembler; a symbol entry will
+ not be emitted into the symbol table. This can prevent `objtool`
+ from generating correct unwind info.
+
+ Symbols with STB_LOCAL binding may still be used, and `.L` prefixed
+ local symbol names are still generally usable within a function,
+ but `.L` prefixed local symbol names should not be used to denote
+ the beginning or end of code regions via
+ `SYM_CODE_START_LOCAL`/`SYM_CODE_END`
+
+ **BIT_MACRO**
+ Defines like: 1 << <digit> could be BIT(digit).
+ The BIT() macro is defined in include/linux/bitops.h::
+
+ #define BIT(nr) (1UL << (nr))
+
+ **CONSIDER_KSTRTO**
+ The simple_strtol(), simple_strtoll(), simple_strtoul(), and
+ simple_strtoull() functions explicitly ignore overflows, which
+ may lead to unexpected results in callers. The respective kstrtol(),
+ kstrtoll(), kstrtoul(), and kstrtoull() functions tend to be the
+ correct replacements.
+ Ref: `Documentation/process/deprecated.rst`
+
+
+Comment style
+-------------
+
+ **BLOCK_COMMENT_STYLE**
+ The comment style is i
+ ncorrect. The preferred style for multi-
+ line comments is::
+
+ /*
+ * This is the preferred style
+ * for multi line comments.
+ */
+
+ The networking comment style is a bit different, with the first line
+ not empty like the former::
+
+ /* This is the preferred comment style
+ * for files in net/ and drivers/net/
+ */
+
+ Ref: `Documentation/process/coding-style.rst`
+
+ **C99_COMMENTS**
+ C99 style single line comments (//) should not be used.
+ Prefer the block comment style instead.
+ Ref: `Documentation/process/coding-style.rst section 8`
+
+
+Commit message
+--------------
+
+ **BAD_SIGN_OFF**
+ The signed-off-by line does not fall in line with the standards
+ specified by the community.
+ Ref: `Documentation/process/submitting-patches.rst`
+
+ **BAD_STABLE_ADDRESS_STYLE**
+ The email format for stable is incorrect.
+ Some valid options for stable address are::
+
+ 1. stable@vger.kernel.org
+ 2. stable@kernel.org
+
+ For adding version info, the following comment style should be used::
+
+ stable@vger.kernel.org # version info
+
+ **COMMIT_COMMENT_SYMBOL**
+ Commit log lines starting with a '#' are ignored by git as
+ comments. To solve this problem addition of a single space
+ infront of the log line is enough.
+
+ **COMMIT_MESSAGE**
+ The patch is missing a commit description. A brief
+ description of the changes made by the patch should be added.
+ Ref: `Documentation/process/submitting-patches.rst`
+
+ **MISSING_SIGN_OFF**
+ The patch is missing a Signed-off-by line. A signed-off-by
+ line should be added according to Developer's certificate of
+ Origin.
+ Ref: `Documentation/process/submitting-patches.rst`
+
+ **NO_AUTHOR_SIGN_OFF**
+ The author of the patch has not signed off the patch. It is
+ required that a simple sign off line should be present at the
+ end of explanation of the patch to denote that the author has
+ written it or otherwise has the rights to pass it on as an open
+ source patch.
+ Ref: `Documentation/process/submitting-patches.rst`
+
+
+Comparison style
+----------------
+
+ **ASSIGN_IN_IF**
+ Do not use assignments in if condition.
+ Example::
+
+ if ((foo = bar(...)) < BAZ) {
+
+ should be written as::
+
+ foo = bar(...);
+ if (foo < BAZ) {
+
+ **BOOL_COMPARISON**
+ Comparisons of A to true and false are better written
+ as A and !A.
+ Ref: `https://lore.kernel.org/lkml/1365563834.27174.12.camel@joe-AO722/`
+
+ **COMPARISON_TO_NULL**
+ Comparisons to NULL in the form (foo == NULL) or (foo != NULL)
+ are better written as (!foo) and (foo).
+
+ **CONSTANT_COMPARISON**
+ Comparisons with a constant or upper case identifier on the left
+ side of the test should be avoided.
+
+
+Spacing and Brackets
+--------------------
+
+ **ASSIGNMENT_CONTINUATIONS**
+ Assignment operators should not be written at the start of a
+ line but should follow the operand at the previous line.
+
+ **BRACES**
+ The placement of braces is stylistically incorrect.
+ The preferred way is to put the opening brace last on the line,
+ and put the closing brace first::
+
+ if (x is true) {
+ we do y
+ }
+
+ This applies for all non-functional blocks.
+ However, there is one special case, namely functions: they have the
+ opening brace at the beginning of the next line, thus::
+
+ int function(int x)
+ {
+ body of function
+ }
+
+ Ref: `Documentation/process/coding-style.rst section 3`
+
+ **BRACKET_SPACE**
+ Whitespace before opening bracket '[' is prohibited.
+ There are some exceptions:
+
+ 1. With a type on the left::
+
+ ;int [] a;
+
+ 2. At the beginning of a line for slice initialisers::
+
+ [0...10] = 5,
+
+ 3. Inside a curly brace::
+
+ = { [0...10] = 5 }
+
+ **CODE_INDENT**
+ Code indent should use tabs instead of spaces.
+ Outside of comments, documentation and Kconfig,
+ spaces are never used for indentation.
+ Ref: `Documentation/process/coding-style.rst section 1`
+
+ **CONCATENATED_STRING**
+ Concatenated elements should have a space in between.
+ Example::
+
+ printk(KERN_INFO"bar");
+
+ should be::
+
+ printk(KERN_INFO "bar");
+
+ **LINE_SPACING**
+ Vertical space is wasted given the limited number of lines an
+ editor window can display when multiple blank lines are used.
+ Ref: `Documentation/process/coding-style.rst section 3.1`
+
+ **SPACING**
+ Whitespace style used in the kernel sources is described in
+ Ref: `Documentation/process/coding-style.rst section 3.1`
+
+ **TRAILING_WHITESPACE**
+ Trailing whitespace should always be removed.
+ Some editors highlight the trailing whitespace and cause visual
+ distractions when editing files.
+
+
+Others
+------
+
+ **CAMELCASE**
+ Avoid CamelCase Identifiers. snake_case can be an
+ alternative.
+ Ref: `Documentation/process/coding-style.rst section 4`
+
+ **CONFIG_DESCRIPTION**
+ Kconfig symbols should have a help text which fully describes
+ it.
diff --git a/Documentation/dev-tools/index.rst b/Documentation/dev-tools/index.rst
index 1b1cf4f5c9d9..43d28998118b 100644
--- a/Documentation/dev-tools/index.rst
+++ b/Documentation/dev-tools/index.rst
@@ -14,6 +14,7 @@ whole; patches welcome!
.. toctree::
:maxdepth: 2
+ checkpatch
coccinelle
sparse
kcov
--
2.30.0
^ permalink raw reply related [flat|nested] 6+ messages in thread