[RFC v3] scripts: kernel-doc: reduce repeated regex expressions into variables

From: Aditya Srivastava
Date: Thu Apr 29 2021 - 02:37:45 EST


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@xxxxxxx>
Signed-off-by: Aditya Srivastava <yashsri421@xxxxxxxxx>
---
Changes in v3:
- Remove variables for separate qualifiers in "sub dump_struct"
- Make a common variable for all the qualifiers
- Make $attribute global variable to use it at "sub check_sections" as well

Changes in v2:
- Rename $pointer_function to $function_pointer
- Combine elsif-block expressions at "sub dump_function" into lesser regex expressions
- Combine $prototype_end1,$prototype_end2 expressions into a common $prototype_end

scripts/kernel-doc | 71 ++++++++++++++++++++++------------------------
1 file changed, 34 insertions(+), 37 deletions(-)

diff --git a/scripts/kernel-doc b/scripts/kernel-doc
index 2a85d34fdcd0..721005a02e64 100755
--- a/scripts/kernel-doc
+++ b/scripts/kernel-doc
@@ -406,6 +406,8 @@ my $doc_inline_sect = '\s*\*\s*(@\s*[\w][\w\.]*\s*):(.*)';
my $doc_inline_end = '^\s*\*/\s*$';
my $doc_inline_oneline = '^\s*/\*\*\s*(@[\w\s]+):\s*(.*)\s*\*/\s*$';
my $export_symbol = '^\s*EXPORT_SYMBOL(_GPL)?\s*\(\s*(\w+)\s*\)\s*;';
+my $function_pointer = qr{([^\(]*\(\*)\s*\)\s*\(([^\)]*)\)};
+my $attribute = qr{__attribute__\s*\(\([a-z0-9,_\*\s\(\)]*\)\)}i;

my %parameterdescs;
my %parameterdesc_start_lines;
@@ -694,7 +696,7 @@ sub output_function_man(%) {
$post = ");";
}
$type = $args{'parametertypes'}{$parameter};
- if ($type =~ m/([^\(]*\(\*)\s*\)\s*\(([^\)]*)\)/) {
+ if ($type =~ m/$function_pointer/) {
# pointer-to-function
print ".BI \"" . $parenth . $1 . "\" " . " \") (" . $2 . ")" . $post . "\"\n";
} else {
@@ -974,7 +976,7 @@ sub output_function_rst(%) {
$count++;
$type = $args{'parametertypes'}{$parameter};

- if ($type =~ m/([^\(]*\(\*)\s*\)\s*\(([^\)]*)\)/) {
+ if ($type =~ m/$function_pointer/) {
# pointer-to-function
print $1 . $parameter . ") (" . $2 . ")";
} else {
@@ -1211,7 +1213,9 @@ sub dump_struct($$) {
my $members;
my $type = qr{struct|union};
# For capturing struct/union definition body, i.e. "{members*}qualifiers*"
- my $definition_body = qr{\{(.*)\}(?:\s*(?:__packed|__aligned|____cacheline_aligned_in_smp|____cacheline_aligned|__attribute__\s*\(\([a-z0-9,_\s\(\)]*\)\)))*};
+ my $qualifiers = qr{$attribute|__packed|__aligned|____cacheline_aligned_in_smp|____cacheline_aligned};
+ my $definition_body = qr{\{(.*)\}\s*$qualifiers*};
+ my $struct_members = qr{($type)([^\{\};]+)\{([^\{\}]*)\}([^\{\}\;]*)\;};

if ($x =~ /($type)\s+(\w+)\s*$definition_body/) {
$decl_type = $1;
@@ -1235,27 +1239,27 @@ sub dump_struct($$) {
# strip comments:
$members =~ s/\/\*.*?\*\///gos;
# strip attributes
- $members =~ s/\s*__attribute__\s*\(\([a-z0-9,_\*\s\(\)]*\)\)/ /gi;
+ $members =~ s/\s*$attribute/ /gi;
$members =~ s/\s*__aligned\s*\([^;]*\)/ /gos;
$members =~ s/\s*__packed\s*/ /gos;
$members =~ s/\s*CRYPTO_MINALIGN_ATTR/ /gos;
$members =~ s/\s*____cacheline_aligned_in_smp/ /gos;
$members =~ s/\s*____cacheline_aligned/ /gos;

+ my $args = qr{([^,)]+)};
# replace DECLARE_BITMAP
$members =~ s/__ETHTOOL_DECLARE_LINK_MODE_MASK\s*\(([^\)]+)\)/DECLARE_BITMAP($1, __ETHTOOL_LINK_MODE_MASK_NBITS)/gos;
- $members =~ s/DECLARE_BITMAP\s*\(([^,)]+),\s*([^,)]+)\)/unsigned long $1\[BITS_TO_LONGS($2)\]/gos;
+ $members =~ s/DECLARE_BITMAP\s*\($args,\s*$args\)/unsigned long $1\[BITS_TO_LONGS($2)\]/gos;
# replace DECLARE_HASHTABLE
- $members =~ s/DECLARE_HASHTABLE\s*\(([^,)]+),\s*([^,)]+)\)/unsigned long $1\[1 << (($2) - 1)\]/gos;
+ $members =~ s/DECLARE_HASHTABLE\s*\($args,\s*$args\)/unsigned long $1\[1 << (($2) - 1)\]/gos;
# replace DECLARE_KFIFO
- $members =~ s/DECLARE_KFIFO\s*\(([^,)]+),\s*([^,)]+),\s*([^,)]+)\)/$2 \*$1/gos;
+ $members =~ s/DECLARE_KFIFO\s*\($args,\s*$args,\s*$args\)/$2 \*$1/gos;
# replace DECLARE_KFIFO_PTR
- $members =~ s/DECLARE_KFIFO_PTR\s*\(([^,)]+),\s*([^,)]+)\)/$2 \*$1/gos;
-
+ $members =~ s/DECLARE_KFIFO_PTR\s*\($args,\s*$args\)/$2 \*$1/gos;
my $declaration = $members;

# Split nested struct/union elements as newer ones
- while ($members =~ m/(struct|union)([^\{\};]+)\{([^\{\}]*)\}([^\{\}\;]*)\;/) {
+ while ($members =~ m/$struct_members/) {
my $newmember;
my $maintype = $1;
my $ids = $4;
@@ -1315,7 +1319,7 @@ sub dump_struct($$) {
}
}
}
- $members =~ s/(struct|union)([^\{\};]+)\{([^\{\}]*)\}([^\{\}\;]*)\;/$newmember/;
+ $members =~ s/$struct_members/$newmember/;
}

# Ignore other nested elements, like enums
@@ -1555,8 +1559,9 @@ sub create_parameterlist($$$$) {
my $param;

# temporarily replace commas inside function pointer definition
- while ($args =~ /(\([^\),]+),/) {
- $args =~ s/(\([^\),]+),/$1#/g;
+ my $arg_expr = qr{\([^\),]+};
+ while ($args =~ /$arg_expr,/) {
+ $args =~ s/($arg_expr),/$1#/g;
}

foreach my $arg (split($splitter, $args)) {
@@ -1707,7 +1712,7 @@ sub check_sections($$$$$) {
foreach $px (0 .. $#prms) {
$prm_clean = $prms[$px];
$prm_clean =~ s/\[.*\]//;
- $prm_clean =~ s/__attribute__\s*\(\([a-z,_\*\s\(\)]*\)\)//i;
+ $prm_clean =~ s/$attribute//i;
# ignore array size in a parameter string;
# however, the original param string may contain
# spaces, e.g.: addr[6 + 2]
@@ -1808,8 +1813,14 @@ sub dump_function($$) {
# - parport_register_device (function pointer parameters)
# - atomic_set (macro)
# - pci_match_device, __copy_to_user (long return type)
-
- if ($define && $prototype =~ m/^()([a-zA-Z0-9_~:]+)\s+/) {
+ my $name = qr{[a-zA-Z0-9_~:]+};
+ my $prototype_end1 = qr{[^\(]*};
+ my $prototype_end2 = qr{[^\{]*};
+ my $prototype_end = qr{\(($prototype_end1|$prototype_end2)\)};
+ my $type1 = qr{[\w\s]+};
+ my $type2 = qr{$type1\*+};
+
+ if ($define && $prototype =~ m/^()($name)\s+/) {
# This is an object-like macro, it has no return type and no parameter
# list.
# Function-like macros are not allowed to have spaces between
@@ -1817,23 +1828,9 @@ sub dump_function($$) {
$return_type = $1;
$declaration_name = $2;
$noret = 1;
- } elsif ($prototype =~ m/^()([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
- $prototype =~ m/^(\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
- $prototype =~ m/^(\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+\s+\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+\s+\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
- $prototype =~ m/^()([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
- $prototype =~ m/^(\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
- $prototype =~ m/^(\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+\s+\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+\s+\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+\s+\w+\s+\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+\s+\w+\s+\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
- $prototype =~ m/^(\w+\s+\w+\s*\*+\s*\w+\s*\*+\s*)\s*([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/) {
+ } elsif ($prototype =~ m/^()($name)\s*$prototype_end/ ||
+ $prototype =~ m/^($type1)\s+($name)\s*$prototype_end/ ||
+ $prototype =~ m/^($type2)+\s*($name)\s*$prototype_end/) {
$return_type = $1;
$declaration_name = $2;
my $args = $3;
@@ -2110,12 +2107,12 @@ sub process_name($$) {
} elsif (/$doc_decl/o) {
$identifier = $1;
my $is_kernel_comment = 0;
- my $decl_start = qr{\s*\*};
+ my $decl_start = qr{$doc_com};
# test for pointer declaration type, foo * bar() - desc
my $fn_type = qr{\w+\s*\*\s*};
my $parenthesis = qr{\(\w*\)};
my $decl_end = qr{[-:].*};
- if (/^$decl_start\s*([\w\s]+?)$parenthesis?\s*$decl_end?$/) {
+ if (/^$decl_start([\w\s]+?)$parenthesis?\s*$decl_end?$/) {
$identifier = $1;
}
if ($identifier =~ m/^(struct|union|enum|typedef)\b\s*(\S*)/) {
@@ -2125,8 +2122,8 @@ sub process_name($$) {
}
# Look for foo() or static void foo() - description; or misspelt
# identifier
- elsif (/^$decl_start\s*$fn_type?(\w+)\s*$parenthesis?\s*$decl_end?$/ ||
- /^$decl_start\s*$fn_type?(\w+.*)$parenthesis?\s*$decl_end$/) {
+ elsif (/^$decl_start$fn_type?(\w+)\s*$parenthesis?\s*$decl_end?$/ ||
+ /^$decl_start$fn_type?(\w+.*)$parenthesis?\s*$decl_end$/) {
$identifier = $1;
$decl_type = 'function';
$identifier =~ s/^define\s+//;
--
2.17.1