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-rw-r--r--scripts/lib/kdoc/kdoc_files.py291
-rw-r--r--scripts/lib/kdoc/kdoc_item.py42
-rw-r--r--scripts/lib/kdoc/kdoc_output.py749
-rw-r--r--scripts/lib/kdoc/kdoc_parser.py1669
-rw-r--r--scripts/lib/kdoc/kdoc_re.py270
5 files changed, 3021 insertions, 0 deletions
diff --git a/scripts/lib/kdoc/kdoc_files.py b/scripts/lib/kdoc/kdoc_files.py
new file mode 100644
index 000000000000..9e09b45b02fa
--- /dev/null
+++ b/scripts/lib/kdoc/kdoc_files.py
@@ -0,0 +1,291 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+# Copyright(c) 2025: Mauro Carvalho Chehab <mchehab@kernel.org>.
+#
+# pylint: disable=R0903,R0913,R0914,R0917
+
+"""
+Parse lernel-doc tags on multiple kernel source files.
+"""
+
+import argparse
+import logging
+import os
+import re
+
+from kdoc_parser import KernelDoc
+from kdoc_output import OutputFormat
+
+
+class GlobSourceFiles:
+ """
+ Parse C source code file names and directories via an Interactor.
+ """
+
+ def __init__(self, srctree=None, valid_extensions=None):
+ """
+ Initialize valid extensions with a tuple.
+
+ If not defined, assume default C extensions (.c and .h)
+
+ It would be possible to use python's glob function, but it is
+ very slow, and it is not interactive. So, it would wait to read all
+ directories before actually do something.
+
+ So, let's use our own implementation.
+ """
+
+ if not valid_extensions:
+ self.extensions = (".c", ".h")
+ else:
+ self.extensions = valid_extensions
+
+ self.srctree = srctree
+
+ def _parse_dir(self, dirname):
+ """Internal function to parse files recursively"""
+
+ with os.scandir(dirname) as obj:
+ for entry in obj:
+ name = os.path.join(dirname, entry.name)
+
+ if entry.is_dir():
+ yield from self._parse_dir(name)
+
+ if not entry.is_file():
+ continue
+
+ basename = os.path.basename(name)
+
+ if not basename.endswith(self.extensions):
+ continue
+
+ yield name
+
+ def parse_files(self, file_list, file_not_found_cb):
+ """
+ Define an interator to parse all source files from file_list,
+ handling directories if any
+ """
+
+ if not file_list:
+ return
+
+ for fname in file_list:
+ if self.srctree:
+ f = os.path.join(self.srctree, fname)
+ else:
+ f = fname
+
+ if os.path.isdir(f):
+ yield from self._parse_dir(f)
+ elif os.path.isfile(f):
+ yield f
+ elif file_not_found_cb:
+ file_not_found_cb(fname)
+
+
+class KernelFiles():
+ """
+ Parse kernel-doc tags on multiple kernel source files.
+
+ There are two type of parsers defined here:
+ - self.parse_file(): parses both kernel-doc markups and
+ EXPORT_SYMBOL* macros;
+ - self.process_export_file(): parses only EXPORT_SYMBOL* macros.
+ """
+
+ def warning(self, msg):
+ """Ancillary routine to output a warning and increment error count"""
+
+ self.config.log.warning(msg)
+ self.errors += 1
+
+ def error(self, msg):
+ """Ancillary routine to output an error and increment error count"""
+
+ self.config.log.error(msg)
+ self.errors += 1
+
+ def parse_file(self, fname):
+ """
+ Parse a single Kernel source.
+ """
+
+ # Prevent parsing the same file twice if results are cached
+ if fname in self.files:
+ return
+
+ doc = KernelDoc(self.config, fname)
+ export_table, entries = doc.parse_kdoc()
+
+ self.export_table[fname] = export_table
+
+ self.files.add(fname)
+ self.export_files.add(fname) # parse_kdoc() already check exports
+
+ self.results[fname] = entries
+
+ def process_export_file(self, fname):
+ """
+ Parses EXPORT_SYMBOL* macros from a single Kernel source file.
+ """
+
+ # Prevent parsing the same file twice if results are cached
+ if fname in self.export_files:
+ return
+
+ doc = KernelDoc(self.config, fname)
+ export_table = doc.parse_export()
+
+ if not export_table:
+ self.error(f"Error: Cannot check EXPORT_SYMBOL* on {fname}")
+ export_table = set()
+
+ self.export_table[fname] = export_table
+ self.export_files.add(fname)
+
+ def file_not_found_cb(self, fname):
+ """
+ Callback to warn if a file was not found.
+ """
+
+ self.error(f"Cannot find file {fname}")
+
+ def __init__(self, verbose=False, out_style=None,
+ werror=False, wreturn=False, wshort_desc=False,
+ wcontents_before_sections=False,
+ logger=None):
+ """
+ Initialize startup variables and parse all files
+ """
+
+ if not verbose:
+ verbose = bool(os.environ.get("KBUILD_VERBOSE", 0))
+
+ if out_style is None:
+ out_style = OutputFormat()
+
+ if not werror:
+ kcflags = os.environ.get("KCFLAGS", None)
+ if kcflags:
+ match = re.search(r"(\s|^)-Werror(\s|$)/", kcflags)
+ if match:
+ werror = True
+
+ # reading this variable is for backwards compat just in case
+ # someone was calling it with the variable from outside the
+ # kernel's build system
+ kdoc_werror = os.environ.get("KDOC_WERROR", None)
+ if kdoc_werror:
+ werror = kdoc_werror
+
+ # Some variables are global to the parser logic as a whole as they are
+ # used to send control configuration to KernelDoc class. As such,
+ # those variables are read-only inside the KernelDoc.
+ self.config = argparse.Namespace
+
+ self.config.verbose = verbose
+ self.config.werror = werror
+ self.config.wreturn = wreturn
+ self.config.wshort_desc = wshort_desc
+ self.config.wcontents_before_sections = wcontents_before_sections
+
+ if not logger:
+ self.config.log = logging.getLogger("kernel-doc")
+ else:
+ self.config.log = logger
+
+ self.config.warning = self.warning
+
+ self.config.src_tree = os.environ.get("SRCTREE", None)
+
+ # Initialize variables that are internal to KernelFiles
+
+ self.out_style = out_style
+
+ self.errors = 0
+ self.results = {}
+
+ self.files = set()
+ self.export_files = set()
+ self.export_table = {}
+
+ def parse(self, file_list, export_file=None):
+ """
+ Parse all files
+ """
+
+ glob = GlobSourceFiles(srctree=self.config.src_tree)
+
+ for fname in glob.parse_files(file_list, self.file_not_found_cb):
+ self.parse_file(fname)
+
+ for fname in glob.parse_files(export_file, self.file_not_found_cb):
+ self.process_export_file(fname)
+
+ def out_msg(self, fname, name, arg):
+ """
+ Return output messages from a file name using the output style
+ filtering.
+
+ If output type was not handled by the syler, return None.
+ """
+
+ # NOTE: we can add rules here to filter out unwanted parts,
+ # although OutputFormat.msg already does that.
+
+ return self.out_style.msg(fname, name, arg)
+
+ def msg(self, enable_lineno=False, export=False, internal=False,
+ symbol=None, nosymbol=None, no_doc_sections=False,
+ filenames=None, export_file=None):
+ """
+ Interacts over the kernel-doc results and output messages,
+ returning kernel-doc markups on each interaction
+ """
+
+ self.out_style.set_config(self.config)
+
+ if not filenames:
+ filenames = sorted(self.results.keys())
+
+ glob = GlobSourceFiles(srctree=self.config.src_tree)
+
+ for fname in filenames:
+ function_table = set()
+
+ if internal or export:
+ if not export_file:
+ export_file = [fname]
+
+ for f in glob.parse_files(export_file, self.file_not_found_cb):
+ function_table |= self.export_table[f]
+
+ if symbol:
+ for s in symbol:
+ function_table.add(s)
+
+ self.out_style.set_filter(export, internal, symbol, nosymbol,
+ function_table, enable_lineno,
+ no_doc_sections)
+
+ msg = ""
+ if fname not in self.results:
+ self.config.log.warning("No kernel-doc for file %s", fname)
+ continue
+
+ for arg in self.results[fname]:
+ m = self.out_msg(fname, arg.name, arg)
+
+ if m is None:
+ ln = arg.get("ln", 0)
+ dtype = arg.get('type', "")
+
+ self.config.log.warning("%s:%d Can't handle %s",
+ fname, ln, dtype)
+ else:
+ msg += m
+
+ if msg:
+ yield fname, msg
diff --git a/scripts/lib/kdoc/kdoc_item.py b/scripts/lib/kdoc/kdoc_item.py
new file mode 100644
index 000000000000..b3b225764550
--- /dev/null
+++ b/scripts/lib/kdoc/kdoc_item.py
@@ -0,0 +1,42 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# A class that will, eventually, encapsulate all of the parsed data that we
+# then pass into the output modules.
+#
+
+class KdocItem:
+ def __init__(self, name, type, start_line, **other_stuff):
+ self.name = name
+ self.type = type
+ self.declaration_start_line = start_line
+ self.sections = {}
+ self.sections_start_lines = {}
+ self.parameterlist = []
+ self.parameterdesc_start_lines = []
+ self.parameterdescs = {}
+ self.parametertypes = {}
+ #
+ # Just save everything else into our own dict so that the output
+ # side can grab it directly as before. As we move things into more
+ # structured data, this will, hopefully, fade away.
+ #
+ self.other_stuff = other_stuff
+
+ def get(self, key, default = None):
+ return self.other_stuff.get(key, default)
+
+ def __getitem__(self, key):
+ return self.get(key)
+
+ #
+ # Tracking of section and parameter information.
+ #
+ def set_sections(self, sections, start_lines):
+ self.sections = sections
+ self.section_start_lines = start_lines
+
+ def set_params(self, names, descs, types, starts):
+ self.parameterlist = names
+ self.parameterdescs = descs
+ self.parametertypes = types
+ self.parameterdesc_start_lines = starts
diff --git a/scripts/lib/kdoc/kdoc_output.py b/scripts/lib/kdoc/kdoc_output.py
new file mode 100644
index 000000000000..ea8914537ba0
--- /dev/null
+++ b/scripts/lib/kdoc/kdoc_output.py
@@ -0,0 +1,749 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+# Copyright(c) 2025: Mauro Carvalho Chehab <mchehab@kernel.org>.
+#
+# pylint: disable=C0301,R0902,R0911,R0912,R0913,R0914,R0915,R0917
+
+"""
+Implement output filters to print kernel-doc documentation.
+
+The implementation uses a virtual base class (OutputFormat) which
+contains a dispatches to virtual methods, and some code to filter
+out output messages.
+
+The actual implementation is done on one separate class per each type
+of output. Currently, there are output classes for ReST and man/troff.
+"""
+
+import os
+import re
+from datetime import datetime
+
+from kdoc_parser import KernelDoc, type_param
+from kdoc_re import KernRe
+
+
+function_pointer = KernRe(r"([^\(]*\(\*)\s*\)\s*\(([^\)]*)\)", cache=False)
+
+# match expressions used to find embedded type information
+type_constant = KernRe(r"\b``([^\`]+)``\b", cache=False)
+type_constant2 = KernRe(r"\%([-_*\w]+)", cache=False)
+type_func = KernRe(r"(\w+)\(\)", cache=False)
+type_param_ref = KernRe(r"([\!~\*]?)\@(\w*((\.\w+)|(->\w+))*(\.\.\.)?)", cache=False)
+
+# Special RST handling for func ptr params
+type_fp_param = KernRe(r"\@(\w+)\(\)", cache=False)
+
+# Special RST handling for structs with func ptr params
+type_fp_param2 = KernRe(r"\@(\w+->\S+)\(\)", cache=False)
+
+type_env = KernRe(r"(\$\w+)", cache=False)
+type_enum = KernRe(r"\&(enum\s*([_\w]+))", cache=False)
+type_struct = KernRe(r"\&(struct\s*([_\w]+))", cache=False)
+type_typedef = KernRe(r"\&(typedef\s*([_\w]+))", cache=False)
+type_union = KernRe(r"\&(union\s*([_\w]+))", cache=False)
+type_member = KernRe(r"\&([_\w]+)(\.|->)([_\w]+)", cache=False)
+type_fallback = KernRe(r"\&([_\w]+)", cache=False)
+type_member_func = type_member + KernRe(r"\(\)", cache=False)
+
+
+class OutputFormat:
+ """
+ Base class for OutputFormat. If used as-is, it means that only
+ warnings will be displayed.
+ """
+
+ # output mode.
+ OUTPUT_ALL = 0 # output all symbols and doc sections
+ OUTPUT_INCLUDE = 1 # output only specified symbols
+ OUTPUT_EXPORTED = 2 # output exported symbols
+ OUTPUT_INTERNAL = 3 # output non-exported symbols
+
+ # Virtual member to be overriden at the inherited classes
+ highlights = []
+
+ def __init__(self):
+ """Declare internal vars and set mode to OUTPUT_ALL"""
+
+ self.out_mode = self.OUTPUT_ALL
+ self.enable_lineno = None
+ self.nosymbol = {}
+ self.symbol = None
+ self.function_table = None
+ self.config = None
+ self.no_doc_sections = False
+
+ self.data = ""
+
+ def set_config(self, config):
+ """
+ Setup global config variables used by both parser and output.
+ """
+
+ self.config = config
+
+ def set_filter(self, export, internal, symbol, nosymbol, function_table,
+ enable_lineno, no_doc_sections):
+ """
+ Initialize filter variables according with the requested mode.
+
+ Only one choice is valid between export, internal and symbol.
+
+ The nosymbol filter can be used on all modes.
+ """
+
+ self.enable_lineno = enable_lineno
+ self.no_doc_sections = no_doc_sections
+ self.function_table = function_table
+
+ if symbol:
+ self.out_mode = self.OUTPUT_INCLUDE
+ elif export:
+ self.out_mode = self.OUTPUT_EXPORTED
+ elif internal:
+ self.out_mode = self.OUTPUT_INTERNAL
+ else:
+ self.out_mode = self.OUTPUT_ALL
+
+ if nosymbol:
+ self.nosymbol = set(nosymbol)
+
+
+ def highlight_block(self, block):
+ """
+ Apply the RST highlights to a sub-block of text.
+ """
+
+ for r, sub in self.highlights:
+ block = r.sub(sub, block)
+
+ return block
+
+ def out_warnings(self, args):
+ """
+ Output warnings for identifiers that will be displayed.
+ """
+
+ for log_msg in args.warnings:
+ self.config.warning(log_msg)
+
+ def check_doc(self, name, args):
+ """Check if DOC should be output"""
+
+ if self.no_doc_sections:
+ return False
+
+ if name in self.nosymbol:
+ return False
+
+ if self.out_mode == self.OUTPUT_ALL:
+ self.out_warnings(args)
+ return True
+
+ if self.out_mode == self.OUTPUT_INCLUDE:
+ if name in self.function_table:
+ self.out_warnings(args)
+ return True
+
+ return False
+
+ def check_declaration(self, dtype, name, args):
+ """
+ Checks if a declaration should be output or not based on the
+ filtering criteria.
+ """
+
+ if name in self.nosymbol:
+ return False
+
+ if self.out_mode == self.OUTPUT_ALL:
+ self.out_warnings(args)
+ return True
+
+ if self.out_mode in [self.OUTPUT_INCLUDE, self.OUTPUT_EXPORTED]:
+ if name in self.function_table:
+ return True
+
+ if self.out_mode == self.OUTPUT_INTERNAL:
+ if dtype != "function":
+ self.out_warnings(args)
+ return True
+
+ if name not in self.function_table:
+ self.out_warnings(args)
+ return True
+
+ return False
+
+ def msg(self, fname, name, args):
+ """
+ Handles a single entry from kernel-doc parser
+ """
+
+ self.data = ""
+
+ dtype = args.type
+
+ if dtype == "doc":
+ self.out_doc(fname, name, args)
+ return self.data
+
+ if not self.check_declaration(dtype, name, args):
+ return self.data
+
+ if dtype == "function":
+ self.out_function(fname, name, args)
+ return self.data
+
+ if dtype == "enum":
+ self.out_enum(fname, name, args)
+ return self.data
+
+ if dtype == "typedef":
+ self.out_typedef(fname, name, args)
+ return self.data
+
+ if dtype in ["struct", "union"]:
+ self.out_struct(fname, name, args)
+ return self.data
+
+ # Warn if some type requires an output logic
+ self.config.log.warning("doesn't now how to output '%s' block",
+ dtype)
+
+ return None
+
+ # Virtual methods to be overridden by inherited classes
+ # At the base class, those do nothing.
+ def out_doc(self, fname, name, args):
+ """Outputs a DOC block"""
+
+ def out_function(self, fname, name, args):
+ """Outputs a function"""
+
+ def out_enum(self, fname, name, args):
+ """Outputs an enum"""
+
+ def out_typedef(self, fname, name, args):
+ """Outputs a typedef"""
+
+ def out_struct(self, fname, name, args):
+ """Outputs a struct"""
+
+
+class RestFormat(OutputFormat):
+ """Consts and functions used by ReST output"""
+
+ highlights = [
+ (type_constant, r"``\1``"),
+ (type_constant2, r"``\1``"),
+
+ # Note: need to escape () to avoid func matching later
+ (type_member_func, r":c:type:`\1\2\3\\(\\) <\1>`"),
+ (type_member, r":c:type:`\1\2\3 <\1>`"),
+ (type_fp_param, r"**\1\\(\\)**"),
+ (type_fp_param2, r"**\1\\(\\)**"),
+ (type_func, r"\1()"),
+ (type_enum, r":c:type:`\1 <\2>`"),
+ (type_struct, r":c:type:`\1 <\2>`"),
+ (type_typedef, r":c:type:`\1 <\2>`"),
+ (type_union, r":c:type:`\1 <\2>`"),
+
+ # in rst this can refer to any type
+ (type_fallback, r":c:type:`\1`"),
+ (type_param_ref, r"**\1\2**")
+ ]
+ blankline = "\n"
+
+ sphinx_literal = KernRe(r'^[^.].*::$', cache=False)
+ sphinx_cblock = KernRe(r'^\.\.\ +code-block::', cache=False)
+
+ def __init__(self):
+ """
+ Creates class variables.
+
+ Not really mandatory, but it is a good coding style and makes
+ pylint happy.
+ """
+
+ super().__init__()
+ self.lineprefix = ""
+
+ def print_lineno(self, ln):
+ """Outputs a line number"""
+
+ if self.enable_lineno and ln is not None:
+ ln += 1
+ self.data += f".. LINENO {ln}\n"
+
+ def output_highlight(self, args):
+ """
+ Outputs a C symbol that may require being converted to ReST using
+ the self.highlights variable
+ """
+
+ input_text = args
+ output = ""
+ in_literal = False
+ litprefix = ""
+ block = ""
+
+ for line in input_text.strip("\n").split("\n"):
+
+ # If we're in a literal block, see if we should drop out of it.
+ # Otherwise, pass the line straight through unmunged.
+ if in_literal:
+ if line.strip(): # If the line is not blank
+ # If this is the first non-blank line in a literal block,
+ # figure out the proper indent.
+ if not litprefix:
+ r = KernRe(r'^(\s*)')
+ if r.match(line):
+ litprefix = '^' + r.group(1)
+ else:
+ litprefix = ""
+
+ output += line + "\n"
+ elif not KernRe(litprefix).match(line):
+ in_literal = False
+ else:
+ output += line + "\n"
+ else:
+ output += line + "\n"
+
+ # Not in a literal block (or just dropped out)
+ if not in_literal:
+ block += line + "\n"
+ if self.sphinx_literal.match(line) or self.sphinx_cblock.match(line):
+ in_literal = True
+ litprefix = ""
+ output += self.highlight_block(block)
+ block = ""
+
+ # Handle any remaining block
+ if block:
+ output += self.highlight_block(block)
+
+ # Print the output with the line prefix
+ for line in output.strip("\n").split("\n"):
+ self.data += self.lineprefix + line + "\n"
+
+ def out_section(self, args, out_docblock=False):
+ """
+ Outputs a block section.
+
+ This could use some work; it's used to output the DOC: sections, and
+ starts by putting out the name of the doc section itself, but that
+ tends to duplicate a header already in the template file.
+ """
+ for section, text in args.sections.items():
+ # Skip sections that are in the nosymbol_table
+ if section in self.nosymbol:
+ continue
+
+ if out_docblock:
+ if not self.out_mode == self.OUTPUT_INCLUDE:
+ self.data += f".. _{section}:\n\n"
+ self.data += f'{self.lineprefix}**{section}**\n\n'
+ else:
+ self.data += f'{self.lineprefix}**{section}**\n\n'
+
+ self.print_lineno(args.section_start_lines.get(section, 0))
+ self.output_highlight(text)
+ self.data += "\n"
+ self.data += "\n"
+
+ def out_doc(self, fname, name, args):
+ if not self.check_doc(name, args):
+ return
+ self.out_section(args, out_docblock=True)
+
+ def out_function(self, fname, name, args):
+
+ oldprefix = self.lineprefix
+ signature = ""
+
+ func_macro = args.get('func_macro', False)
+ if func_macro:
+ signature = name
+ else:
+ if args.get('functiontype'):
+ signature = args['functiontype'] + " "
+ signature += name + " ("
+
+ ln = args.declaration_start_line
+ count = 0
+ for parameter in args.parameterlist:
+ if count != 0:
+ signature += ", "
+ count += 1
+ dtype = args.parametertypes.get(parameter, "")
+
+ if function_pointer.search(dtype):
+ signature += function_pointer.group(1) + parameter + function_pointer.group(3)
+ else:
+ signature += dtype
+
+ if not func_macro:
+ signature += ")"
+
+ self.print_lineno(ln)
+ if args.get('typedef') or not args.get('functiontype'):
+ self.data += f".. c:macro:: {name}\n\n"
+
+ if args.get('typedef'):
+ self.data += " **Typedef**: "
+ self.lineprefix = ""
+ self.output_highlight(args.get('purpose', ""))
+ self.data += "\n\n**Syntax**\n\n"
+ self.data += f" ``{signature}``\n\n"
+ else:
+ self.data += f"``{signature}``\n\n"
+ else:
+ self.data += f".. c:function:: {signature}\n\n"
+
+ if not args.get('typedef'):
+ self.print_lineno(ln)
+ self.lineprefix = " "
+ self.output_highlight(args.get('purpose', ""))
+ self.data += "\n"
+
+ # Put descriptive text into a container (HTML <div>) to help set
+ # function prototypes apart
+ self.lineprefix = " "
+
+ if args.parameterlist:
+ self.data += ".. container:: kernelindent\n\n"
+ self.data += f"{self.lineprefix}**Parameters**\n\n"
+
+ for parameter in args.parameterlist:
+ parameter_name = KernRe(r'\[.*').sub('', parameter)
+ dtype = args.parametertypes.get(parameter, "")
+
+ if dtype:
+ self.data += f"{self.lineprefix}``{dtype}``\n"
+ else:
+ self.data += f"{self.lineprefix}``{parameter}``\n"
+
+ self.print_lineno(args.parameterdesc_start_lines.get(parameter_name, 0))
+
+ self.lineprefix = " "
+ if parameter_name in args.parameterdescs and \
+ args.parameterdescs[parameter_name] != KernelDoc.undescribed:
+
+ self.output_highlight(args.parameterdescs[parameter_name])
+ self.data += "\n"
+ else:
+ self.data += f"{self.lineprefix}*undescribed*\n\n"
+ self.lineprefix = " "
+
+ self.out_section(args)
+ self.lineprefix = oldprefix
+
+ def out_enum(self, fname, name, args):
+
+ oldprefix = self.lineprefix
+ ln = args.declaration_start_line
+
+ self.data += f"\n\n.. c:enum:: {name}\n\n"
+
+ self.print_lineno(ln)
+ self.lineprefix = " "
+ self.output_highlight(args.get('purpose', ''))
+ self.data += "\n"
+
+ self.data += ".. container:: kernelindent\n\n"
+ outer = self.lineprefix + " "
+ self.lineprefix = outer + " "
+ self.data += f"{outer}**Constants**\n\n"
+
+ for parameter in args.parameterlist:
+ self.data += f"{outer}``{parameter}``\n"
+
+ if args.parameterdescs.get(parameter, '') != KernelDoc.undescribed:
+ self.output_highlight(args.parameterdescs[parameter])
+ else:
+ self.data += f"{self.lineprefix}*undescribed*\n\n"
+ self.data += "\n"
+
+ self.lineprefix = oldprefix
+ self.out_section(args)
+
+ def out_typedef(self, fname, name, args):
+
+ oldprefix = self.lineprefix
+ ln = args.declaration_start_line
+
+ self.data += f"\n\n.. c:type:: {name}\n\n"
+
+ self.print_lineno(ln)
+ self.lineprefix = " "
+
+ self.output_highlight(args.get('purpose', ''))
+
+ self.data += "\n"
+
+ self.lineprefix = oldprefix
+ self.out_section(args)
+
+ def out_struct(self, fname, name, args):
+
+ purpose = args.get('purpose', "")
+ declaration = args.get('definition', "")
+ dtype = args.type
+ ln = args.declaration_start_line
+
+ self.data += f"\n\n.. c:{dtype}:: {name}\n\n"
+
+ self.print_lineno(ln)
+
+ oldprefix = self.lineprefix
+ self.lineprefix += " "
+
+ self.output_highlight(purpose)
+ self.data += "\n"
+
+ self.data += ".. container:: kernelindent\n\n"
+ self.data += f"{self.lineprefix}**Definition**::\n\n"
+
+ self.lineprefix = self.lineprefix + " "
+
+ declaration = declaration.replace("\t", self.lineprefix)
+
+ self.data += f"{self.lineprefix}{dtype} {name}" + ' {' + "\n"
+ self.data += f"{declaration}{self.lineprefix}" + "};\n\n"
+
+ self.lineprefix = " "
+ self.data += f"{self.lineprefix}**Members**\n\n"
+ for parameter in args.parameterlist:
+ if not parameter or parameter.startswith("#"):
+ continue
+
+ parameter_name = parameter.split("[", maxsplit=1)[0]
+
+ if args.parameterdescs.get(parameter_name) == KernelDoc.undescribed:
+ continue
+
+ self.print_lineno(args.parameterdesc_start_lines.get(parameter_name, 0))
+
+ self.data += f"{self.lineprefix}``{parameter}``\n"
+
+ self.lineprefix = " "
+ self.output_highlight(args.parameterdescs[parameter_name])
+ self.lineprefix = " "
+
+ self.data += "\n"
+
+ self.data += "\n"
+
+ self.lineprefix = oldprefix
+ self.out_section(args)
+
+
+class ManFormat(OutputFormat):
+ """Consts and functions used by man pages output"""
+
+ highlights = (
+ (type_constant, r"\1"),
+ (type_constant2, r"\1"),
+ (type_func, r"\\fB\1\\fP"),
+ (type_enum, r"\\fI\1\\fP"),
+ (type_struct, r"\\fI\1\\fP"),
+ (type_typedef, r"\\fI\1\\fP"),
+ (type_union, r"\\fI\1\\fP"),
+ (type_param, r"\\fI\1\\fP"),
+ (type_param_ref, r"\\fI\1\2\\fP"),
+ (type_member, r"\\fI\1\2\3\\fP"),
+ (type_fallback, r"\\fI\1\\fP")
+ )
+ blankline = ""
+
+ date_formats = [
+ "%a %b %d %H:%M:%S %Z %Y",
+ "%a %b %d %H:%M:%S %Y",
+ "%Y-%m-%d",
+ "%b %d %Y",
+ "%B %d %Y",
+ "%m %d %Y",
+ ]
+
+ def __init__(self, modulename):
+ """
+ Creates class variables.
+
+ Not really mandatory, but it is a good coding style and makes
+ pylint happy.
+ """
+
+ super().__init__()
+ self.modulename = modulename
+
+ dt = None
+ tstamp = os.environ.get("KBUILD_BUILD_TIMESTAMP")
+ if tstamp:
+ for fmt in self.date_formats:
+ try:
+ dt = datetime.strptime(tstamp, fmt)
+ break
+ except ValueError:
+ pass
+
+ if not dt:
+ dt = datetime.now()
+
+ self.man_date = dt.strftime("%B %Y")
+
+ def output_highlight(self, block):
+ """
+ Outputs a C symbol that may require being highlighted with
+ self.highlights variable using troff syntax
+ """
+
+ contents = self.highlight_block(block)
+
+ if isinstance(contents, list):
+ contents = "\n".join(contents)
+
+ for line in contents.strip("\n").split("\n"):
+ line = KernRe(r"^\s*").sub("", line)
+ if not line:
+ continue
+
+ if line[0] == ".":
+ self.data += "\\&" + line + "\n"
+ else:
+ self.data += line + "\n"
+
+ def out_doc(self, fname, name, args):
+ if not self.check_doc(name, args):
+ return
+
+ self.data += f'.TH "{self.modulename}" 9 "{self.modulename}" "{self.man_date}" "API Manual" LINUX' + "\n"
+
+ for section, text in args.sections.items():
+ self.data += f'.SH "{section}"' + "\n"
+ self.output_highlight(text)
+
+ def out_function(self, fname, name, args):
+ """output function in man"""
+
+ self.data += f'.TH "{name}" 9 "{name}" "{self.man_date}" "Kernel Hacker\'s Manual" LINUX' + "\n"
+
+ self.data += ".SH NAME\n"
+ self.data += f"{name} \\- {args['purpose']}\n"
+
+ self.data += ".SH SYNOPSIS\n"
+ if args.get('functiontype', ''):
+ self.data += f'.B "{args["functiontype"]}" {name}' + "\n"
+ else:
+ self.data += f'.B "{name}' + "\n"
+
+ count = 0
+ parenth = "("
+ post = ","
+
+ for parameter in args.parameterlist:
+ if count == len(args.parameterlist) - 1:
+ post = ");"
+
+ dtype = args.parametertypes.get(parameter, "")
+ if function_pointer.match(dtype):
+ # Pointer-to-function
+ self.data += f'".BI "{parenth}{function_pointer.group(1)}" " ") ({function_pointer.group(2)}){post}"' + "\n"
+ else:
+ dtype = KernRe(r'([^\*])$').sub(r'\1 ', dtype)
+
+ self.data += f'.BI "{parenth}{dtype}" "{post}"' + "\n"
+ count += 1
+ parenth = ""
+
+ if args.parameterlist:
+ self.data += ".SH ARGUMENTS\n"
+
+ for parameter in args.parameterlist:
+ parameter_name = re.sub(r'\[.*', '', parameter)
+
+ self.data += f'.IP "{parameter}" 12' + "\n"
+ self.output_highlight(args.parameterdescs.get(parameter_name, ""))
+
+ for section, text in args.sections.items():
+ self.data += f'.SH "{section.upper()}"' + "\n"
+ self.output_highlight(text)
+
+ def out_enum(self, fname, name, args):
+ self.data += f'.TH "{self.modulename}" 9 "enum {name}" "{self.man_date}" "API Manual" LINUX' + "\n"
+
+ self.data += ".SH NAME\n"
+ self.data += f"enum {name} \\- {args['purpose']}\n"
+
+ self.data += ".SH SYNOPSIS\n"
+ self.data += f"enum {name}" + " {\n"
+
+ count = 0
+ for parameter in args.parameterlist:
+ self.data += f'.br\n.BI " {parameter}"' + "\n"
+ if count == len(args.parameterlist) - 1:
+ self.data += "\n};\n"
+ else:
+ self.data += ", \n.br\n"
+
+ count += 1
+
+ self.data += ".SH Constants\n"
+
+ for parameter in args.parameterlist:
+ parameter_name = KernRe(r'\[.*').sub('', parameter)
+ self.data += f'.IP "{parameter}" 12' + "\n"
+ self.output_highlight(args.parameterdescs.get(parameter_name, ""))
+
+ for section, text in args.sections.items():
+ self.data += f'.SH "{section}"' + "\n"
+ self.output_highlight(text)
+
+ def out_typedef(self, fname, name, args):
+ module = self.modulename
+ purpose = args.get('purpose')
+
+ self.data += f'.TH "{module}" 9 "{name}" "{self.man_date}" "API Manual" LINUX' + "\n"
+
+ self.data += ".SH NAME\n"
+ self.data += f"typedef {name} \\- {purpose}\n"
+
+ for section, text in args.sections.items():
+ self.data += f'.SH "{section}"' + "\n"
+ self.output_highlight(text)
+
+ def out_struct(self, fname, name, args):
+ module = self.modulename
+ purpose = args.get('purpose')
+ definition = args.get('definition')
+
+ self.data += f'.TH "{module}" 9 "{args.type} {name}" "{self.man_date}" "API Manual" LINUX' + "\n"
+
+ self.data += ".SH NAME\n"
+ self.data += f"{args.type} {name} \\- {purpose}\n"
+
+ # Replace tabs with two spaces and handle newlines
+ declaration = definition.replace("\t", " ")
+ declaration = KernRe(r"\n").sub('"\n.br\n.BI "', declaration)
+
+ self.data += ".SH SYNOPSIS\n"
+ self.data += f"{args.type} {name} " + "{" + "\n.br\n"
+ self.data += f'.BI "{declaration}\n' + "};\n.br\n\n"
+
+ self.data += ".SH Members\n"
+ for parameter in args.parameterlist:
+ if parameter.startswith("#"):
+ continue
+
+ parameter_name = re.sub(r"\[.*", "", parameter)
+
+ if args.parameterdescs.get(parameter_name) == KernelDoc.undescribed:
+ continue
+
+ self.data += f'.IP "{parameter}" 12' + "\n"
+ self.output_highlight(args.parameterdescs.get(parameter_name))
+
+ for section, text in args.sections.items():
+ self.data += f'.SH "{section}"' + "\n"
+ self.output_highlight(text)
diff --git a/scripts/lib/kdoc/kdoc_parser.py b/scripts/lib/kdoc/kdoc_parser.py
new file mode 100644
index 000000000000..fe730099eca8
--- /dev/null
+++ b/scripts/lib/kdoc/kdoc_parser.py
@@ -0,0 +1,1669 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+# Copyright(c) 2025: Mauro Carvalho Chehab <mchehab@kernel.org>.
+#
+# pylint: disable=C0301,C0302,R0904,R0912,R0913,R0914,R0915,R0917,R1702
+
+"""
+kdoc_parser
+===========
+
+Read a C language source or header FILE and extract embedded
+documentation comments
+"""
+
+import sys
+import re
+from pprint import pformat
+
+from kdoc_re import NestedMatch, KernRe
+from kdoc_item import KdocItem
+
+#
+# Regular expressions used to parse kernel-doc markups at KernelDoc class.
+#
+# Let's declare them in lowercase outside any class to make easier to
+# convert from the python script.
+#
+# As those are evaluated at the beginning, no need to cache them
+#
+
+# Allow whitespace at end of comment start.
+doc_start = KernRe(r'^/\*\*\s*$', cache=False)
+
+doc_end = KernRe(r'\*/', cache=False)
+doc_com = KernRe(r'\s*\*\s*', cache=False)
+doc_com_body = KernRe(r'\s*\* ?', cache=False)
+doc_decl = doc_com + KernRe(r'(\w+)', cache=False)
+
+# @params and a strictly limited set of supported section names
+# Specifically:
+# Match @word:
+# @...:
+# @{section-name}:
+# while trying to not match literal block starts like "example::"
+#
+known_section_names = 'description|context|returns?|notes?|examples?'
+known_sections = KernRe(known_section_names, flags = re.I)
+doc_sect = doc_com + \
+ KernRe(r'\s*(\@[.\w]+|\@\.\.\.|' + known_section_names + r')\s*:([^:].*)?$',
+ flags=re.I, cache=False)
+
+doc_content = doc_com_body + KernRe(r'(.*)', cache=False)
+doc_inline_start = KernRe(r'^\s*/\*\*\s*$', cache=False)
+doc_inline_sect = KernRe(r'\s*\*\s*(@\s*[\w][\w\.]*\s*):(.*)', cache=False)
+doc_inline_end = KernRe(r'^\s*\*/\s*$', cache=False)
+doc_inline_oneline = KernRe(r'^\s*/\*\*\s*(@[\w\s]+):\s*(.*)\s*\*/\s*$', cache=False)
+attribute = KernRe(r"__attribute__\s*\(\([a-z0-9,_\*\s\(\)]*\)\)",
+ flags=re.I | re.S, cache=False)
+
+export_symbol = KernRe(r'^\s*EXPORT_SYMBOL(_GPL)?\s*\(\s*(\w+)\s*\)\s*', cache=False)
+export_symbol_ns = KernRe(r'^\s*EXPORT_SYMBOL_NS(_GPL)?\s*\(\s*(\w+)\s*,\s*"\S+"\)\s*', cache=False)
+
+type_param = KernRe(r"\@(\w*((\.\w+)|(->\w+))*(\.\.\.)?)", cache=False)
+
+#
+# Tests for the beginning of a kerneldoc block in its various forms.
+#
+doc_block = doc_com + KernRe(r'DOC:\s*(.*)?', cache=False)
+doc_begin_data = KernRe(r"^\s*\*?\s*(struct|union|enum|typedef)\b\s*(\w*)", cache = False)
+doc_begin_func = KernRe(str(doc_com) + # initial " * '
+ r"(?:\w+\s*\*\s*)?" + # type (not captured)
+ r'(?:define\s+)?' + # possible "define" (not captured)
+ r'(\w+)\s*(?:\(\w*\))?\s*' + # name and optional "(...)"
+ r'(?:[-:].*)?$', # description (not captured)
+ cache = False)
+
+#
+# A little helper to get rid of excess white space
+#
+multi_space = KernRe(r'\s\s+')
+def trim_whitespace(s):
+ return multi_space.sub(' ', s.strip())
+
+class state:
+ """
+ State machine enums
+ """
+
+ # Parser states
+ NORMAL = 0 # normal code
+ NAME = 1 # looking for function name
+ DECLARATION = 2 # We have seen a declaration which might not be done
+ BODY = 3 # the body of the comment
+ SPECIAL_SECTION = 4 # doc section ending with a blank line
+ PROTO = 5 # scanning prototype
+ DOCBLOCK = 6 # documentation block
+ INLINE_NAME = 7 # gathering doc outside main block
+ INLINE_TEXT = 8 # reading the body of inline docs
+
+ name = [
+ "NORMAL",
+ "NAME",
+ "DECLARATION",
+ "BODY",
+ "SPECIAL_SECTION",
+ "PROTO",
+ "DOCBLOCK",
+ "INLINE_NAME",
+ "INLINE_TEXT",
+ ]
+
+
+SECTION_DEFAULT = "Description" # default section
+
+class KernelEntry:
+
+ def __init__(self, config, ln):
+ self.config = config
+
+ self._contents = []
+ self.prototype = ""
+
+ self.warnings = []
+
+ self.parameterlist = []
+ self.parameterdescs = {}
+ self.parametertypes = {}
+ self.parameterdesc_start_lines = {}
+
+ self.section_start_lines = {}
+ self.sections = {}
+
+ self.anon_struct_union = False
+
+ self.leading_space = None
+
+ # State flags
+ self.brcount = 0
+ self.declaration_start_line = ln + 1
+
+ #
+ # Management of section contents
+ #
+ def add_text(self, text):
+ self._contents.append(text)
+
+ def contents(self):
+ return '\n'.join(self._contents) + '\n'
+
+ # TODO: rename to emit_message after removal of kernel-doc.pl
+ def emit_msg(self, log_msg, warning=True):
+ """Emit a message"""
+
+ if not warning:
+ self.config.log.info(log_msg)
+ return
+
+ # Delegate warning output to output logic, as this way it
+ # will report warnings/info only for symbols that are output
+
+ self.warnings.append(log_msg)
+ return
+
+ #
+ # Begin a new section.
+ #
+ def begin_section(self, line_no, title = SECTION_DEFAULT, dump = False):
+ if dump:
+ self.dump_section(start_new = True)
+ self.section = title
+ self.new_start_line = line_no
+
+ def dump_section(self, start_new=True):
+ """
+ Dumps section contents to arrays/hashes intended for that purpose.
+ """
+ #
+ # If we have accumulated no contents in the default ("description")
+ # section, don't bother.
+ #
+ if self.section == SECTION_DEFAULT and not self._contents:
+ return
+ name = self.section
+ contents = self.contents()
+
+ if type_param.match(name):
+ name = type_param.group(1)
+
+ self.parameterdescs[name] = contents
+ self.parameterdesc_start_lines[name] = self.new_start_line
+
+ self.new_start_line = 0
+
+ else:
+ if name in self.sections and self.sections[name] != "":
+ # Only warn on user-specified duplicate section names
+ if name != SECTION_DEFAULT:
+ self.emit_msg(self.new_start_line,
+ f"duplicate section name '{name}'\n")
+ # Treat as a new paragraph - add a blank line
+ self.sections[name] += '\n' + contents
+ else:
+ self.sections[name] = contents
+ self.section_start_lines[name] = self.new_start_line
+ self.new_start_line = 0
+
+# self.config.log.debug("Section: %s : %s", name, pformat(vars(self)))
+
+ if start_new:
+ self.section = SECTION_DEFAULT
+ self._contents = []
+
+
+class KernelDoc:
+ """
+ Read a C language source or header FILE and extract embedded
+ documentation comments.
+ """
+
+ # Section names
+
+ section_context = "Context"
+ section_return = "Return"
+
+ undescribed = "-- undescribed --"
+
+ def __init__(self, config, fname):
+ """Initialize internal variables"""
+
+ self.fname = fname
+ self.config = config
+
+ # Initial state for the state machines
+ self.state = state.NORMAL
+
+ # Store entry currently being processed
+ self.entry = None
+
+ # Place all potential outputs into an array
+ self.entries = []
+
+ #
+ # We need Python 3.7 for its "dicts remember the insertion
+ # order" guarantee
+ #
+ if sys.version_info.major == 3 and sys.version_info.minor < 7:
+ self.emit_msg(0,
+ 'Python 3.7 or later is required for correct results')
+
+ def emit_msg(self, ln, msg, warning=True):
+ """Emit a message"""
+
+ log_msg = f"{self.fname}:{ln} {msg}"
+
+ if self.entry:
+ self.entry.emit_msg(log_msg, warning)
+ return
+
+ if warning:
+ self.config.log.warning(log_msg)
+ else:
+ self.config.log.info(log_msg)
+
+ def dump_section(self, start_new=True):
+ """
+ Dumps section contents to arrays/hashes intended for that purpose.
+ """
+
+ if self.entry:
+ self.entry.dump_section(start_new)
+
+ # TODO: rename it to store_declaration after removal of kernel-doc.pl
+ def output_declaration(self, dtype, name, **args):
+ """
+ Stores the entry into an entry array.
+
+ The actual output and output filters will be handled elsewhere
+ """
+
+ item = KdocItem(name, dtype, self.entry.declaration_start_line, **args)
+ item.warnings = self.entry.warnings
+
+ # Drop empty sections
+ # TODO: improve empty sections logic to emit warnings
+ sections = self.entry.sections
+ for section in ["Description", "Return"]:
+ if section in sections and not sections[section].rstrip():
+ del sections[section]
+ item.set_sections(sections, self.entry.section_start_lines)
+ item.set_params(self.entry.parameterlist, self.entry.parameterdescs,
+ self.entry.parametertypes,
+ self.entry.parameterdesc_start_lines)
+ self.entries.append(item)
+
+ self.config.log.debug("Output: %s:%s = %s", dtype, name, pformat(args))
+
+ def reset_state(self, ln):
+ """
+ Ancillary routine to create a new entry. It initializes all
+ variables used by the state machine.
+ """
+
+ self.entry = KernelEntry(self.config, ln)
+
+ # State flags
+ self.state = state.NORMAL
+
+ def push_parameter(self, ln, decl_type, param, dtype,
+ org_arg, declaration_name):
+ """
+ Store parameters and their descriptions at self.entry.
+ """
+
+ if self.entry.anon_struct_union and dtype == "" and param == "}":
+ return # Ignore the ending }; from anonymous struct/union
+
+ self.entry.anon_struct_union = False
+
+ param = KernRe(r'[\[\)].*').sub('', param, count=1)
+
+ if dtype == "" and param.endswith("..."):
+ if KernRe(r'\w\.\.\.$').search(param):
+ # For named variable parameters of the form `x...`,
+ # remove the dots
+ param = param[:-3]
+ else:
+ # Handles unnamed variable parameters
+ param = "..."
+
+ if param not in self.entry.parameterdescs or \
+ not self.entry.parameterdescs[param]:
+
+ self.entry.parameterdescs[param] = "variable arguments"
+
+ elif dtype == "" and (not param or param == "void"):
+ param = "void"
+ self.entry.parameterdescs[param] = "no arguments"
+
+ elif dtype == "" and param in ["struct", "union"]:
+ # Handle unnamed (anonymous) union or struct
+ dtype = param
+ param = "{unnamed_" + param + "}"
+ self.entry.parameterdescs[param] = "anonymous\n"
+ self.entry.anon_struct_union = True
+
+ # Handle cache group enforcing variables: they do not need
+ # to be described in header files
+ elif "__cacheline_group" in param:
+ # Ignore __cacheline_group_begin and __cacheline_group_end
+ return
+
+ # Warn if parameter has no description
+ # (but ignore ones starting with # as these are not parameters
+ # but inline preprocessor statements)
+ if param not in self.entry.parameterdescs and not param.startswith("#"):
+ self.entry.parameterdescs[param] = self.undescribed
+
+ if "." not in param:
+ if decl_type == 'function':
+ dname = f"{decl_type} parameter"
+ else:
+ dname = f"{decl_type} member"
+
+ self.emit_msg(ln,
+ f"{dname} '{param}' not described in '{declaration_name}'")
+
+ # Strip spaces from param so that it is one continuous string on
+ # parameterlist. This fixes a problem where check_sections()
+ # cannot find a parameter like "addr[6 + 2]" because it actually
+ # appears as "addr[6", "+", "2]" on the parameter list.
+ # However, it's better to maintain the param string unchanged for
+ # output, so just weaken the string compare in check_sections()
+ # to ignore "[blah" in a parameter string.
+
+ self.entry.parameterlist.append(param)
+ org_arg = KernRe(r'\s\s+').sub(' ', org_arg)
+ self.entry.parametertypes[param] = org_arg
+
+
+ def create_parameter_list(self, ln, decl_type, args,
+ splitter, declaration_name):
+ """
+ Creates a list of parameters, storing them at self.entry.
+ """
+
+ # temporarily replace all commas inside function pointer definition
+ arg_expr = KernRe(r'(\([^\),]+),')
+ while arg_expr.search(args):
+ args = arg_expr.sub(r"\1#", args)
+
+ for arg in args.split(splitter):
+ # Strip comments
+ arg = KernRe(r'\/\*.*\*\/').sub('', arg)
+
+ # Ignore argument attributes
+ arg = KernRe(r'\sPOS0?\s').sub(' ', arg)
+
+ # Strip leading/trailing spaces
+ arg = arg.strip()
+ arg = KernRe(r'\s+').sub(' ', arg, count=1)
+
+ if arg.startswith('#'):
+ # Treat preprocessor directive as a typeless variable just to fill
+ # corresponding data structures "correctly". Catch it later in
+ # output_* subs.
+
+ # Treat preprocessor directive as a typeless variable
+ self.push_parameter(ln, decl_type, arg, "",
+ "", declaration_name)
+
+ elif KernRe(r'\(.+\)\s*\(').search(arg):
+ # Pointer-to-function
+
+ arg = arg.replace('#', ',')
+
+ r = KernRe(r'[^\(]+\(\*?\s*([\w\[\]\.]*)\s*\)')
+ if r.match(arg):
+ param = r.group(1)
+ else:
+ self.emit_msg(ln, f"Invalid param: {arg}")
+ param = arg
+
+ dtype = KernRe(r'([^\(]+\(\*?)\s*' + re.escape(param)).sub(r'\1', arg)
+ self.push_parameter(ln, decl_type, param, dtype,
+ arg, declaration_name)
+
+ elif KernRe(r'\(.+\)\s*\[').search(arg):
+ # Array-of-pointers
+
+ arg = arg.replace('#', ',')
+ r = KernRe(r'[^\(]+\(\s*\*\s*([\w\[\]\.]*?)\s*(\s*\[\s*[\w]+\s*\]\s*)*\)')
+ if r.match(arg):
+ param = r.group(1)
+ else:
+ self.emit_msg(ln, f"Invalid param: {arg}")
+ param = arg
+
+ dtype = KernRe(r'([^\(]+\(\*?)\s*' + re.escape(param)).sub(r'\1', arg)
+
+ self.push_parameter(ln, decl_type, param, dtype,
+ arg, declaration_name)
+
+ elif arg:
+ arg = KernRe(r'\s*:\s*').sub(":", arg)
+ arg = KernRe(r'\s*\[').sub('[', arg)
+
+ args = KernRe(r'\s*,\s*').split(arg)
+ if args[0] and '*' in args[0]:
+ args[0] = re.sub(r'(\*+)\s*', r' \1', args[0])
+
+ first_arg = []
+ r = KernRe(r'^(.*\s+)(.*?\[.*\].*)$')
+ if args[0] and r.match(args[0]):
+ args.pop(0)
+ first_arg.extend(r.group(1))
+ first_arg.append(r.group(2))
+ else:
+ first_arg = KernRe(r'\s+').split(args.pop(0))
+
+ args.insert(0, first_arg.pop())
+ dtype = ' '.join(first_arg)
+
+ for param in args:
+ if KernRe(r'^(\*+)\s*(.*)').match(param):
+ r = KernRe(r'^(\*+)\s*(.*)')
+ if not r.match(param):
+ self.emit_msg(ln, f"Invalid param: {param}")
+ continue
+
+ param = r.group(1)
+
+ self.push_parameter(ln, decl_type, r.group(2),
+ f"{dtype} {r.group(1)}",
+ arg, declaration_name)
+
+ elif KernRe(r'(.*?):(\w+)').search(param):
+ r = KernRe(r'(.*?):(\w+)')
+ if not r.match(param):
+ self.emit_msg(ln, f"Invalid param: {param}")
+ continue
+
+ if dtype != "": # Skip unnamed bit-fields
+ self.push_parameter(ln, decl_type, r.group(1),
+ f"{dtype}:{r.group(2)}",
+ arg, declaration_name)
+ else:
+ self.push_parameter(ln, decl_type, param, dtype,
+ arg, declaration_name)
+
+ def check_sections(self, ln, decl_name, decl_type):
+ """
+ Check for errors inside sections, emitting warnings if not found
+ parameters are described.
+ """
+ for section in self.entry.sections:
+ if section not in self.entry.parameterlist and \
+ not known_sections.search(section):
+ if decl_type == 'function':
+ dname = f"{decl_type} parameter"
+ else:
+ dname = f"{decl_type} member"
+ self.emit_msg(ln,
+ f"Excess {dname} '{section}' description in '{decl_name}'")
+
+ def check_return_section(self, ln, declaration_name, return_type):
+ """
+ If the function doesn't return void, warns about the lack of a
+ return description.
+ """
+
+ if not self.config.wreturn:
+ return
+
+ # Ignore an empty return type (It's a macro)
+ # Ignore functions with a "void" return type (but not "void *")
+ if not return_type or KernRe(r'void\s*\w*\s*$').search(return_type):
+ return
+
+ if not self.entry.sections.get("Return", None):
+ self.emit_msg(ln,
+ f"No description found for return value of '{declaration_name}'")
+
+ def dump_struct(self, ln, proto):
+ """
+ Store an entry for an struct or union
+ """
+
+ type_pattern = r'(struct|union)'
+
+ qualifiers = [
+ "__attribute__",
+ "__packed",
+ "__aligned",
+ "____cacheline_aligned_in_smp",
+ "____cacheline_aligned",
+ ]
+
+ definition_body = r'\{(.*)\}\s*' + "(?:" + '|'.join(qualifiers) + ")?"
+ struct_members = KernRe(type_pattern + r'([^\{\};]+)(\{)([^\{\}]*)(\})([^\{\}\;]*)(\;)')
+
+ # Extract struct/union definition
+ members = None
+ declaration_name = None
+ decl_type = None
+
+ r = KernRe(type_pattern + r'\s+(\w+)\s*' + definition_body)
+ if r.search(proto):
+ decl_type = r.group(1)
+ declaration_name = r.group(2)
+ members = r.group(3)
+ else:
+ r = KernRe(r'typedef\s+' + type_pattern + r'\s*' + definition_body + r'\s*(\w+)\s*;')
+
+ if r.search(proto):
+ decl_type = r.group(1)
+ declaration_name = r.group(3)
+ members = r.group(2)
+
+ if not members:
+ self.emit_msg(ln, f"{proto} error: Cannot parse struct or union!")
+ return
+
+ if self.entry.identifier != declaration_name:
+ self.emit_msg(ln,
+ f"expecting prototype for {decl_type} {self.entry.identifier}. Prototype was for {decl_type} {declaration_name} instead\n")
+ return
+
+ args_pattern = r'([^,)]+)'
+
+ sub_prefixes = [
+ (KernRe(r'\/\*\s*private:.*?\/\*\s*public:.*?\*\/', re.S | re.I), ''),
+ (KernRe(r'\/\*\s*private:.*', re.S | re.I), ''),
+
+ # Strip comments
+ (KernRe(r'\/\*.*?\*\/', re.S), ''),
+
+ # Strip attributes
+ (attribute, ' '),
+ (KernRe(r'\s*__aligned\s*\([^;]*\)', re.S), ' '),
+ (KernRe(r'\s*__counted_by\s*\([^;]*\)', re.S), ' '),
+ (KernRe(r'\s*__counted_by_(le|be)\s*\([^;]*\)', re.S), ' '),
+ (KernRe(r'\s*__packed\s*', re.S), ' '),
+ (KernRe(r'\s*CRYPTO_MINALIGN_ATTR', re.S), ' '),
+ (KernRe(r'\s*____cacheline_aligned_in_smp', re.S), ' '),
+ (KernRe(r'\s*____cacheline_aligned', re.S), ' '),
+
+ # Unwrap struct_group macros based on this definition:
+ # __struct_group(TAG, NAME, ATTRS, MEMBERS...)
+ # which has variants like: struct_group(NAME, MEMBERS...)
+ # Only MEMBERS arguments require documentation.
+ #
+ # Parsing them happens on two steps:
+ #
+ # 1. drop struct group arguments that aren't at MEMBERS,
+ # storing them as STRUCT_GROUP(MEMBERS)
+ #
+ # 2. remove STRUCT_GROUP() ancillary macro.
+ #
+ # The original logic used to remove STRUCT_GROUP() using an
+ # advanced regex:
+ #
+ # \bSTRUCT_GROUP(\(((?:(?>[^)(]+)|(?1))*)\))[^;]*;
+ #
+ # with two patterns that are incompatible with
+ # Python re module, as it has:
+ #
+ # - a recursive pattern: (?1)
+ # - an atomic grouping: (?>...)
+ #
+ # I tried a simpler version: but it didn't work either:
+ # \bSTRUCT_GROUP\(([^\)]+)\)[^;]*;
+ #
+ # As it doesn't properly match the end parenthesis on some cases.
+ #
+ # So, a better solution was crafted: there's now a NestedMatch
+ # class that ensures that delimiters after a search are properly
+ # matched. So, the implementation to drop STRUCT_GROUP() will be
+ # handled in separate.
+
+ (KernRe(r'\bstruct_group\s*\(([^,]*,)', re.S), r'STRUCT_GROUP('),
+ (KernRe(r'\bstruct_group_attr\s*\(([^,]*,){2}', re.S), r'STRUCT_GROUP('),
+ (KernRe(r'\bstruct_group_tagged\s*\(([^,]*),([^,]*),', re.S), r'struct \1 \2; STRUCT_GROUP('),
+ (KernRe(r'\b__struct_group\s*\(([^,]*,){3}', re.S), r'STRUCT_GROUP('),
+
+ # Replace macros
+ #
+ # TODO: use NestedMatch for FOO($1, $2, ...) matches
+ #
+ # it is better to also move those to the NestedMatch logic,
+ # to ensure that parenthesis will be properly matched.
+
+ (KernRe(r'__ETHTOOL_DECLARE_LINK_MODE_MASK\s*\(([^\)]+)\)', re.S), r'DECLARE_BITMAP(\1, __ETHTOOL_LINK_MODE_MASK_NBITS)'),
+ (KernRe(r'DECLARE_PHY_INTERFACE_MASK\s*\(([^\)]+)\)', re.S), r'DECLARE_BITMAP(\1, PHY_INTERFACE_MODE_MAX)'),
+ (KernRe(r'DECLARE_BITMAP\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'unsigned long \1[BITS_TO_LONGS(\2)]'),
+ (KernRe(r'DECLARE_HASHTABLE\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'unsigned long \1[1 << ((\2) - 1)]'),
+ (KernRe(r'DECLARE_KFIFO\s*\(' + args_pattern + r',\s*' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'\2 *\1'),
+ (KernRe(r'DECLARE_KFIFO_PTR\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'\2 *\1'),
+ (KernRe(r'(?:__)?DECLARE_FLEX_ARRAY\s*\(' + args_pattern + r',\s*' + args_pattern + r'\)', re.S), r'\1 \2[]'),
+ (KernRe(r'DEFINE_DMA_UNMAP_ADDR\s*\(' + args_pattern + r'\)', re.S), r'dma_addr_t \1'),
+ (KernRe(r'DEFINE_DMA_UNMAP_LEN\s*\(' + args_pattern + r'\)', re.S), r'__u32 \1'),
+ (KernRe(r'VIRTIO_DECLARE_FEATURES\s*\(' + args_pattern + r'\)', re.S), r'u64 \1; u64 \1_array[VIRTIO_FEATURES_DWORDS]'),
+ ]
+
+ # Regexes here are guaranteed to have the end limiter matching
+ # the start delimiter. Yet, right now, only one replace group
+ # is allowed.
+
+ sub_nested_prefixes = [
+ (re.compile(r'\bSTRUCT_GROUP\('), r'\1'),
+ ]
+
+ for search, sub in sub_prefixes:
+ members = search.sub(sub, members)
+
+ nested = NestedMatch()
+
+ for search, sub in sub_nested_prefixes:
+ members = nested.sub(search, sub, members)
+
+ # Keeps the original declaration as-is
+ declaration = members
+
+ # Split nested struct/union elements
+ #
+ # This loop was simpler at the original kernel-doc perl version, as
+ # while ($members =~ m/$struct_members/) { ... }
+ # reads 'members' string on each interaction.
+ #
+ # Python behavior is different: it parses 'members' only once,
+ # creating a list of tuples from the first interaction.
+ #
+ # On other words, this won't get nested structs.
+ #
+ # So, we need to have an extra loop on Python to override such
+ # re limitation.
+
+ while True:
+ tuples = struct_members.findall(members)
+ if not tuples:
+ break
+
+ for t in tuples:
+ newmember = ""
+ maintype = t[0]
+ s_ids = t[5]
+ content = t[3]
+
+ oldmember = "".join(t)
+
+ for s_id in s_ids.split(','):
+ s_id = s_id.strip()
+
+ newmember += f"{maintype} {s_id}; "
+ s_id = KernRe(r'[:\[].*').sub('', s_id)
+ s_id = KernRe(r'^\s*\**(\S+)\s*').sub(r'\1', s_id)
+
+ for arg in content.split(';'):
+ arg = arg.strip()
+
+ if not arg:
+ continue
+
+ r = KernRe(r'^([^\(]+\(\*?\s*)([\w\.]*)(\s*\).*)')
+ if r.match(arg):
+ # Pointer-to-function
+ dtype = r.group(1)
+ name = r.group(2)
+ extra = r.group(3)
+
+ if not name:
+ continue
+
+ if not s_id:
+ # Anonymous struct/union
+ newmember += f"{dtype}{name}{extra}; "
+ else:
+ newmember += f"{dtype}{s_id}.{name}{extra}; "
+
+ else:
+ arg = arg.strip()
+ # Handle bitmaps
+ arg = KernRe(r':\s*\d+\s*').sub('', arg)
+
+ # Handle arrays
+ arg = KernRe(r'\[.*\]').sub('', arg)
+
+ # Handle multiple IDs
+ arg = KernRe(r'\s*,\s*').sub(',', arg)
+
+ r = KernRe(r'(.*)\s+([\S+,]+)')
+
+ if r.search(arg):
+ dtype = r.group(1)
+ names = r.group(2)
+ else:
+ newmember += f"{arg}; "
+ continue
+
+ for name in names.split(','):
+ name = KernRe(r'^\s*\**(\S+)\s*').sub(r'\1', name).strip()
+
+ if not name:
+ continue
+
+ if not s_id:
+ # Anonymous struct/union
+ newmember += f"{dtype} {name}; "
+ else:
+ newmember += f"{dtype} {s_id}.{name}; "
+
+ members = members.replace(oldmember, newmember)
+
+ # Ignore other nested elements, like enums
+ members = re.sub(r'(\{[^\{\}]*\})', '', members)
+
+ self.create_parameter_list(ln, decl_type, members, ';',
+ declaration_name)
+ self.check_sections(ln, declaration_name, decl_type)
+
+ # Adjust declaration for better display
+ declaration = KernRe(r'([\{;])').sub(r'\1\n', declaration)
+ declaration = KernRe(r'\}\s+;').sub('};', declaration)
+
+ # Better handle inlined enums
+ while True:
+ r = KernRe(r'(enum\s+\{[^\}]+),([^\n])')
+ if not r.search(declaration):
+ break
+
+ declaration = r.sub(r'\1,\n\2', declaration)
+
+ def_args = declaration.split('\n')
+ level = 1
+ declaration = ""
+ for clause in def_args:
+
+ clause = clause.strip()
+ clause = KernRe(r'\s+').sub(' ', clause, count=1)
+
+ if not clause:
+ continue
+
+ if '}' in clause and level > 1:
+ level -= 1
+
+ if not KernRe(r'^\s*#').match(clause):
+ declaration += "\t" * level
+
+ declaration += "\t" + clause + "\n"
+ if "{" in clause and "}" not in clause:
+ level += 1
+
+ self.output_declaration(decl_type, declaration_name,
+ definition=declaration,
+ purpose=self.entry.declaration_purpose)
+
+ def dump_enum(self, ln, proto):
+ """
+ Stores an enum inside self.entries array.
+ """
+
+ # Ignore members marked private
+ proto = KernRe(r'\/\*\s*private:.*?\/\*\s*public:.*?\*\/', flags=re.S).sub('', proto)
+ proto = KernRe(r'\/\*\s*private:.*}', flags=re.S).sub('}', proto)
+
+ # Strip comments
+ proto = KernRe(r'\/\*.*?\*\/', flags=re.S).sub('', proto)
+
+ # Strip #define macros inside enums
+ proto = KernRe(r'#\s*((define|ifdef|if)\s+|endif)[^;]*;', flags=re.S).sub('', proto)
+
+ #
+ # Parse out the name and members of the enum. Typedef form first.
+ #
+ r = KernRe(r'typedef\s+enum\s*\{(.*)\}\s*(\w*)\s*;')
+ if r.search(proto):
+ declaration_name = r.group(2)
+ members = r.group(1).rstrip()
+ #
+ # Failing that, look for a straight enum
+ #
+ else:
+ r = KernRe(r'enum\s+(\w*)\s*\{(.*)\}')
+ if r.match(proto):
+ declaration_name = r.group(1)
+ members = r.group(2).rstrip()
+ #
+ # OK, this isn't going to work.
+ #
+ else:
+ self.emit_msg(ln, f"{proto}: error: Cannot parse enum!")
+ return
+ #
+ # Make sure we found what we were expecting.
+ #
+ if self.entry.identifier != declaration_name:
+ if self.entry.identifier == "":
+ self.emit_msg(ln,
+ f"{proto}: wrong kernel-doc identifier on prototype")
+ else:
+ self.emit_msg(ln,
+ f"expecting prototype for enum {self.entry.identifier}. "
+ f"Prototype was for enum {declaration_name} instead")
+ return
+
+ if not declaration_name:
+ declaration_name = "(anonymous)"
+ #
+ # Parse out the name of each enum member, and verify that we
+ # have a description for it.
+ #
+ member_set = set()
+ members = KernRe(r'\([^;)]*\)').sub('', members)
+ for arg in members.split(','):
+ if not arg:
+ continue
+ arg = KernRe(r'^\s*(\w+).*').sub(r'\1', arg)
+ self.entry.parameterlist.append(arg)
+ if arg not in self.entry.parameterdescs:
+ self.entry.parameterdescs[arg] = self.undescribed
+ self.emit_msg(ln,
+ f"Enum value '{arg}' not described in enum '{declaration_name}'")
+ member_set.add(arg)
+ #
+ # Ensure that every described member actually exists in the enum.
+ #
+ for k in self.entry.parameterdescs:
+ if k not in member_set:
+ self.emit_msg(ln,
+ f"Excess enum value '%{k}' description in '{declaration_name}'")
+
+ self.output_declaration('enum', declaration_name,
+ purpose=self.entry.declaration_purpose)
+
+ def dump_declaration(self, ln, prototype):
+ """
+ Stores a data declaration inside self.entries array.
+ """
+
+ if self.entry.decl_type == "enum":
+ self.dump_enum(ln, prototype)
+ elif self.entry.decl_type == "typedef":
+ self.dump_typedef(ln, prototype)
+ elif self.entry.decl_type in ["union", "struct"]:
+ self.dump_struct(ln, prototype)
+ else:
+ # This would be a bug
+ self.emit_message(ln, f'Unknown declaration type: {self.entry.decl_type}')
+
+ def dump_function(self, ln, prototype):
+ """
+ Stores a function of function macro inside self.entries array.
+ """
+
+ func_macro = False
+ return_type = ''
+ decl_type = 'function'
+
+ # Prefixes that would be removed
+ sub_prefixes = [
+ (r"^static +", "", 0),
+ (r"^extern +", "", 0),
+ (r"^asmlinkage +", "", 0),
+ (r"^inline +", "", 0),
+ (r"^__inline__ +", "", 0),
+ (r"^__inline +", "", 0),
+ (r"^__always_inline +", "", 0),
+ (r"^noinline +", "", 0),
+ (r"^__FORTIFY_INLINE +", "", 0),
+ (r"__init +", "", 0),
+ (r"__init_or_module +", "", 0),
+ (r"__deprecated +", "", 0),
+ (r"__flatten +", "", 0),
+ (r"__meminit +", "", 0),
+ (r"__must_check +", "", 0),
+ (r"__weak +", "", 0),
+ (r"__sched +", "", 0),
+ (r"_noprof", "", 0),
+ (r"__printf\s*\(\s*\d*\s*,\s*\d*\s*\) +", "", 0),
+ (r"__(?:re)?alloc_size\s*\(\s*\d+\s*(?:,\s*\d+\s*)?\) +", "", 0),
+ (r"__diagnose_as\s*\(\s*\S+\s*(?:,\s*\d+\s*)*\) +", "", 0),
+ (r"DECL_BUCKET_PARAMS\s*\(\s*(\S+)\s*,\s*(\S+)\s*\)", r"\1, \2", 0),
+ (r"__attribute_const__ +", "", 0),
+
+ # It seems that Python support for re.X is broken:
+ # At least for me (Python 3.13), this didn't work
+# (r"""
+# __attribute__\s*\(\(
+# (?:
+# [\w\s]+ # attribute name
+# (?:\([^)]*\))? # attribute arguments
+# \s*,? # optional comma at the end
+# )+
+# \)\)\s+
+# """, "", re.X),
+
+ # So, remove whitespaces and comments from it
+ (r"__attribute__\s*\(\((?:[\w\s]+(?:\([^)]*\))?\s*,?)+\)\)\s+", "", 0),
+ ]
+
+ for search, sub, flags in sub_prefixes:
+ prototype = KernRe(search, flags).sub(sub, prototype)
+
+ # Macros are a special case, as they change the prototype format
+ new_proto = KernRe(r"^#\s*define\s+").sub("", prototype)
+ if new_proto != prototype:
+ is_define_proto = True
+ prototype = new_proto
+ else:
+ is_define_proto = False
+
+ # Yes, this truly is vile. We are looking for:
+ # 1. Return type (may be nothing if we're looking at a macro)
+ # 2. Function name
+ # 3. Function parameters.
+ #
+ # All the while we have to watch out for function pointer parameters
+ # (which IIRC is what the two sections are for), C types (these
+ # regexps don't even start to express all the possibilities), and
+ # so on.
+ #
+ # If you mess with these regexps, it's a good idea to check that
+ # the following functions' documentation still comes out right:
+ # - parport_register_device (function pointer parameters)
+ # - atomic_set (macro)
+ # - pci_match_device, __copy_to_user (long return type)
+
+ name = r'[a-zA-Z0-9_~:]+'
+ prototype_end1 = r'[^\(]*'
+ prototype_end2 = r'[^\{]*'
+ prototype_end = fr'\(({prototype_end1}|{prototype_end2})\)'
+
+ # Besides compiling, Perl qr{[\w\s]+} works as a non-capturing group.
+ # So, this needs to be mapped in Python with (?:...)? or (?:...)+
+
+ type1 = r'(?:[\w\s]+)?'
+ type2 = r'(?:[\w\s]+\*+)+'
+
+ found = False
+
+ if is_define_proto:
+ r = KernRe(r'^()(' + name + r')\s+')
+
+ if r.search(prototype):
+ return_type = ''
+ declaration_name = r.group(2)
+ func_macro = True
+
+ found = True
+
+ if not found:
+ patterns = [
+ rf'^()({name})\s*{prototype_end}',
+ rf'^({type1})\s+({name})\s*{prototype_end}',
+ rf'^({type2})\s*({name})\s*{prototype_end}',
+ ]
+
+ for p in patterns:
+ r = KernRe(p)
+
+ if r.match(prototype):
+
+ return_type = r.group(1)
+ declaration_name = r.group(2)
+ args = r.group(3)
+
+ self.create_parameter_list(ln, decl_type, args, ',',
+ declaration_name)
+
+ found = True
+ break
+ if not found:
+ self.emit_msg(ln,
+ f"cannot understand function prototype: '{prototype}'")
+ return
+
+ if self.entry.identifier != declaration_name:
+ self.emit_msg(ln,
+ f"expecting prototype for {self.entry.identifier}(). Prototype was for {declaration_name}() instead")
+ return
+
+ self.check_sections(ln, declaration_name, "function")
+
+ self.check_return_section(ln, declaration_name, return_type)
+
+ if 'typedef' in return_type:
+ self.output_declaration(decl_type, declaration_name,
+ typedef=True,
+ functiontype=return_type,
+ purpose=self.entry.declaration_purpose,
+ func_macro=func_macro)
+ else:
+ self.output_declaration(decl_type, declaration_name,
+ typedef=False,
+ functiontype=return_type,
+ purpose=self.entry.declaration_purpose,
+ func_macro=func_macro)
+
+ def dump_typedef(self, ln, proto):
+ """
+ Stores a typedef inside self.entries array.
+ """
+
+ typedef_type = r'((?:\s+[\w\*]+\b){0,7}\s+(?:\w+\b|\*+))\s*'
+ typedef_ident = r'\*?\s*(\w\S+)\s*'
+ typedef_args = r'\s*\((.*)\);'
+
+ typedef1 = KernRe(r'typedef' + typedef_type + r'\(' + typedef_ident + r'\)' + typedef_args)
+ typedef2 = KernRe(r'typedef' + typedef_type + typedef_ident + typedef_args)
+
+ # Strip comments
+ proto = KernRe(r'/\*.*?\*/', flags=re.S).sub('', proto)
+
+ # Parse function typedef prototypes
+ for r in [typedef1, typedef2]:
+ if not r.match(proto):
+ continue
+
+ return_type = r.group(1).strip()
+ declaration_name = r.group(2)
+ args = r.group(3)
+
+ if self.entry.identifier != declaration_name:
+ self.emit_msg(ln,
+ f"expecting prototype for typedef {self.entry.identifier}. Prototype was for typedef {declaration_name} instead\n")
+ return
+
+ decl_type = 'function'
+ self.create_parameter_list(ln, decl_type, args, ',', declaration_name)
+
+ self.output_declaration(decl_type, declaration_name,
+ typedef=True,
+ functiontype=return_type,
+ purpose=self.entry.declaration_purpose)
+ return
+
+ # Handle nested parentheses or brackets
+ r = KernRe(r'(\(*.\)\s*|\[*.\]\s*);$')
+ while r.search(proto):
+ proto = r.sub('', proto)
+
+ # Parse simple typedefs
+ r = KernRe(r'typedef.*\s+(\w+)\s*;')
+ if r.match(proto):
+ declaration_name = r.group(1)
+
+ if self.entry.identifier != declaration_name:
+ self.emit_msg(ln,
+ f"expecting prototype for typedef {self.entry.identifier}. Prototype was for typedef {declaration_name} instead\n")
+ return
+
+ self.output_declaration('typedef', declaration_name,
+ purpose=self.entry.declaration_purpose)
+ return
+
+ self.emit_msg(ln, "error: Cannot parse typedef!")
+
+ @staticmethod
+ def process_export(function_set, line):
+ """
+ process EXPORT_SYMBOL* tags
+
+ This method doesn't use any variable from the class, so declare it
+ with a staticmethod decorator.
+ """
+
+ # We support documenting some exported symbols with different
+ # names. A horrible hack.
+ suffixes = [ '_noprof' ]
+
+ # Note: it accepts only one EXPORT_SYMBOL* per line, as having
+ # multiple export lines would violate Kernel coding style.
+
+ if export_symbol.search(line):
+ symbol = export_symbol.group(2)
+ elif export_symbol_ns.search(line):
+ symbol = export_symbol_ns.group(2)
+ else:
+ return False
+ #
+ # Found an export, trim out any special suffixes
+ #
+ for suffix in suffixes:
+ # Be backward compatible with Python < 3.9
+ if symbol.endswith(suffix):
+ symbol = symbol[:-len(suffix)]
+ function_set.add(symbol)
+ return True
+
+ def process_normal(self, ln, line):
+ """
+ STATE_NORMAL: looking for the /** to begin everything.
+ """
+
+ if not doc_start.match(line):
+ return
+
+ # start a new entry
+ self.reset_state(ln)
+
+ # next line is always the function name
+ self.state = state.NAME
+
+ def process_name(self, ln, line):
+ """
+ STATE_NAME: Looking for the "name - description" line
+ """
+ #
+ # Check for a DOC: block and handle them specially.
+ #
+ if doc_block.search(line):
+
+ if not doc_block.group(1):
+ self.entry.begin_section(ln, "Introduction")
+ else:
+ self.entry.begin_section(ln, doc_block.group(1))
+
+ self.entry.identifier = self.entry.section
+ self.state = state.DOCBLOCK
+ #
+ # Otherwise we're looking for a normal kerneldoc declaration line.
+ #
+ elif doc_decl.search(line):
+ self.entry.identifier = doc_decl.group(1)
+
+ # Test for data declaration
+ if doc_begin_data.search(line):
+ self.entry.decl_type = doc_begin_data.group(1)
+ self.entry.identifier = doc_begin_data.group(2)
+ #
+ # Look for a function description
+ #
+ elif doc_begin_func.search(line):
+ self.entry.identifier = doc_begin_func.group(1)
+ self.entry.decl_type = "function"
+ #
+ # We struck out.
+ #
+ else:
+ self.emit_msg(ln,
+ f"This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst\n{line}")
+ self.state = state.NORMAL
+ return
+ #
+ # OK, set up for a new kerneldoc entry.
+ #
+ self.state = state.BODY
+ self.entry.identifier = self.entry.identifier.strip(" ")
+ # if there's no @param blocks need to set up default section here
+ self.entry.begin_section(ln + 1)
+ #
+ # Find the description portion, which *should* be there but
+ # isn't always.
+ # (We should be able to capture this from the previous parsing - someday)
+ #
+ r = KernRe("[-:](.*)")
+ if r.search(line):
+ self.entry.declaration_purpose = trim_whitespace(r.group(1))
+ self.state = state.DECLARATION
+ else:
+ self.entry.declaration_purpose = ""
+
+ if not self.entry.declaration_purpose and self.config.wshort_desc:
+ self.emit_msg(ln,
+ f"missing initial short description on line:\n{line}")
+
+ if not self.entry.identifier and self.entry.decl_type != "enum":
+ self.emit_msg(ln,
+ f"wrong kernel-doc identifier on line:\n{line}")
+ self.state = state.NORMAL
+
+ if self.config.verbose:
+ self.emit_msg(ln,
+ f"Scanning doc for {self.entry.decl_type} {self.entry.identifier}",
+ warning=False)
+ #
+ # Failed to find an identifier. Emit a warning
+ #
+ else:
+ self.emit_msg(ln, f"Cannot find identifier on line:\n{line}")
+
+ #
+ # Helper function to determine if a new section is being started.
+ #
+ def is_new_section(self, ln, line):
+ if doc_sect.search(line):
+ self.state = state.BODY
+ #
+ # Pick out the name of our new section, tweaking it if need be.
+ #
+ newsection = doc_sect.group(1)
+ if newsection.lower() == 'description':
+ newsection = 'Description'
+ elif newsection.lower() == 'context':
+ newsection = 'Context'
+ self.state = state.SPECIAL_SECTION
+ elif newsection.lower() in ["@return", "@returns",
+ "return", "returns"]:
+ newsection = "Return"
+ self.state = state.SPECIAL_SECTION
+ elif newsection[0] == '@':
+ self.state = state.SPECIAL_SECTION
+ #
+ # Initialize the contents, and get the new section going.
+ #
+ newcontents = doc_sect.group(2)
+ if not newcontents:
+ newcontents = ""
+ self.dump_section()
+ self.entry.begin_section(ln, newsection)
+ self.entry.leading_space = None
+
+ self.entry.add_text(newcontents.lstrip())
+ return True
+ return False
+
+ #
+ # Helper function to detect (and effect) the end of a kerneldoc comment.
+ #
+ def is_comment_end(self, ln, line):
+ if doc_end.search(line):
+ self.dump_section()
+
+ # Look for doc_com + <text> + doc_end:
+ r = KernRe(r'\s*\*\s*[a-zA-Z_0-9:\.]+\*/')
+ if r.match(line):
+ self.emit_msg(ln, f"suspicious ending line: {line}")
+
+ self.entry.prototype = ""
+ self.entry.new_start_line = ln + 1
+
+ self.state = state.PROTO
+ return True
+ return False
+
+
+ def process_decl(self, ln, line):
+ """
+ STATE_DECLARATION: We've seen the beginning of a declaration
+ """
+ if self.is_new_section(ln, line) or self.is_comment_end(ln, line):
+ return
+ #
+ # Look for anything with the " * " line beginning.
+ #
+ if doc_content.search(line):
+ cont = doc_content.group(1)
+ #
+ # A blank line means that we have moved out of the declaration
+ # part of the comment (without any "special section" parameter
+ # descriptions).
+ #
+ if cont == "":
+ self.state = state.BODY
+ #
+ # Otherwise we have more of the declaration section to soak up.
+ #
+ else:
+ self.entry.declaration_purpose = \
+ trim_whitespace(self.entry.declaration_purpose + ' ' + cont)
+ else:
+ # Unknown line, ignore
+ self.emit_msg(ln, f"bad line: {line}")
+
+
+ def process_special(self, ln, line):
+ """
+ STATE_SPECIAL_SECTION: a section ending with a blank line
+ """
+ #
+ # If we have hit a blank line (only the " * " marker), then this
+ # section is done.
+ #
+ if KernRe(r"\s*\*\s*$").match(line):
+ self.entry.begin_section(ln, dump = True)
+ self.state = state.BODY
+ return
+ #
+ # Not a blank line, look for the other ways to end the section.
+ #
+ if self.is_new_section(ln, line) or self.is_comment_end(ln, line):
+ return
+ #
+ # OK, we should have a continuation of the text for this section.
+ #
+ if doc_content.search(line):
+ cont = doc_content.group(1)
+ #
+ # If the lines of text after the first in a special section have
+ # leading white space, we need to trim it out or Sphinx will get
+ # confused. For the second line (the None case), see what we
+ # find there and remember it.
+ #
+ if self.entry.leading_space is None:
+ r = KernRe(r'^(\s+)')
+ if r.match(cont):
+ self.entry.leading_space = len(r.group(1))
+ else:
+ self.entry.leading_space = 0
+ #
+ # Otherwise, before trimming any leading chars, be *sure*
+ # that they are white space. We should maybe warn if this
+ # isn't the case.
+ #
+ for i in range(0, self.entry.leading_space):
+ if cont[i] != " ":
+ self.entry.leading_space = i
+ break
+ #
+ # Add the trimmed result to the section and we're done.
+ #
+ self.entry.add_text(cont[self.entry.leading_space:])
+ else:
+ # Unknown line, ignore
+ self.emit_msg(ln, f"bad line: {line}")
+
+ def process_body(self, ln, line):
+ """
+ STATE_BODY: the bulk of a kerneldoc comment.
+ """
+ if self.is_new_section(ln, line) or self.is_comment_end(ln, line):
+ return
+
+ if doc_content.search(line):
+ cont = doc_content.group(1)
+ self.entry.add_text(cont)
+ else:
+ # Unknown line, ignore
+ self.emit_msg(ln, f"bad line: {line}")
+
+ def process_inline_name(self, ln, line):
+ """STATE_INLINE_NAME: beginning of docbook comments within a prototype."""
+
+ if doc_inline_sect.search(line):
+ self.entry.begin_section(ln, doc_inline_sect.group(1))
+ self.entry.add_text(doc_inline_sect.group(2).lstrip())
+ self.state = state.INLINE_TEXT
+ elif doc_inline_end.search(line):
+ self.dump_section()
+ self.state = state.PROTO
+ elif doc_content.search(line):
+ self.emit_msg(ln, f"Incorrect use of kernel-doc format: {line}")
+ self.state = state.PROTO
+ # else ... ??
+
+ def process_inline_text(self, ln, line):
+ """STATE_INLINE_TEXT: docbook comments within a prototype."""
+
+ if doc_inline_end.search(line):
+ self.dump_section()
+ self.state = state.PROTO
+ elif doc_content.search(line):
+ self.entry.add_text(doc_content.group(1))
+ # else ... ??
+
+ def syscall_munge(self, ln, proto): # pylint: disable=W0613
+ """
+ Handle syscall definitions
+ """
+
+ is_void = False
+
+ # Strip newlines/CR's
+ proto = re.sub(r'[\r\n]+', ' ', proto)
+
+ # Check if it's a SYSCALL_DEFINE0
+ if 'SYSCALL_DEFINE0' in proto:
+ is_void = True
+
+ # Replace SYSCALL_DEFINE with correct return type & function name
+ proto = KernRe(r'SYSCALL_DEFINE.*\(').sub('long sys_', proto)
+
+ r = KernRe(r'long\s+(sys_.*?),')
+ if r.search(proto):
+ proto = KernRe(',').sub('(', proto, count=1)
+ elif is_void:
+ proto = KernRe(r'\)').sub('(void)', proto, count=1)
+
+ # Now delete all of the odd-numbered commas in the proto
+ # so that argument types & names don't have a comma between them
+ count = 0
+ length = len(proto)
+
+ if is_void:
+ length = 0 # skip the loop if is_void
+
+ for ix in range(length):
+ if proto[ix] == ',':
+ count += 1
+ if count % 2 == 1:
+ proto = proto[:ix] + ' ' + proto[ix + 1:]
+
+ return proto
+
+ def tracepoint_munge(self, ln, proto):
+ """
+ Handle tracepoint definitions
+ """
+
+ tracepointname = None
+ tracepointargs = None
+
+ # Match tracepoint name based on different patterns
+ r = KernRe(r'TRACE_EVENT\((.*?),')
+ if r.search(proto):
+ tracepointname = r.group(1)
+
+ r = KernRe(r'DEFINE_SINGLE_EVENT\((.*?),')
+ if r.search(proto):
+ tracepointname = r.group(1)
+
+ r = KernRe(r'DEFINE_EVENT\((.*?),(.*?),')
+ if r.search(proto):
+ tracepointname = r.group(2)
+
+ if tracepointname:
+ tracepointname = tracepointname.lstrip()
+
+ r = KernRe(r'TP_PROTO\((.*?)\)')
+ if r.search(proto):
+ tracepointargs = r.group(1)
+
+ if not tracepointname or not tracepointargs:
+ self.emit_msg(ln,
+ f"Unrecognized tracepoint format:\n{proto}\n")
+ else:
+ proto = f"static inline void trace_{tracepointname}({tracepointargs})"
+ self.entry.identifier = f"trace_{self.entry.identifier}"
+
+ return proto
+
+ def process_proto_function(self, ln, line):
+ """Ancillary routine to process a function prototype"""
+
+ # strip C99-style comments to end of line
+ line = KernRe(r"\/\/.*$", re.S).sub('', line)
+ #
+ # Soak up the line's worth of prototype text, stopping at { or ; if present.
+ #
+ if KernRe(r'\s*#\s*define').match(line):
+ self.entry.prototype = line
+ elif not line.startswith('#'): # skip other preprocessor stuff
+ r = KernRe(r'([^\{]*)')
+ if r.match(line):
+ self.entry.prototype += r.group(1) + " "
+ #
+ # If we now have the whole prototype, clean it up and declare victory.
+ #
+ if '{' in line or ';' in line or KernRe(r'\s*#\s*define').match(line):
+ # strip comments and surrounding spaces
+ self.entry.prototype = KernRe(r'/\*.*\*/').sub('', self.entry.prototype).strip()
+ #
+ # Handle self.entry.prototypes for function pointers like:
+ # int (*pcs_config)(struct foo)
+ # by turning it into
+ # int pcs_config(struct foo)
+ #
+ r = KernRe(r'^(\S+\s+)\(\s*\*(\S+)\)')
+ self.entry.prototype = r.sub(r'\1\2', self.entry.prototype)
+ #
+ # Handle special declaration syntaxes
+ #
+ if 'SYSCALL_DEFINE' in self.entry.prototype:
+ self.entry.prototype = self.syscall_munge(ln,
+ self.entry.prototype)
+ else:
+ r = KernRe(r'TRACE_EVENT|DEFINE_EVENT|DEFINE_SINGLE_EVENT')
+ if r.search(self.entry.prototype):
+ self.entry.prototype = self.tracepoint_munge(ln,
+ self.entry.prototype)
+ #
+ # ... and we're done
+ #
+ self.dump_function(ln, self.entry.prototype)
+ self.reset_state(ln)
+
+ def process_proto_type(self, ln, line):
+ """Ancillary routine to process a type"""
+
+ # Strip C99-style comments and surrounding whitespace
+ line = KernRe(r"//.*$", re.S).sub('', line).strip()
+ if not line:
+ return # nothing to see here
+
+ # To distinguish preprocessor directive from regular declaration later.
+ if line.startswith('#'):
+ line += ";"
+ #
+ # Split the declaration on any of { } or ;, and accumulate pieces
+ # until we hit a semicolon while not inside {brackets}
+ #
+ r = KernRe(r'(.*?)([{};])')
+ for chunk in r.split(line):
+ if chunk: # Ignore empty matches
+ self.entry.prototype += chunk
+ #
+ # This cries out for a match statement ... someday after we can
+ # drop Python 3.9 ...
+ #
+ if chunk == '{':
+ self.entry.brcount += 1
+ elif chunk == '}':
+ self.entry.brcount -= 1
+ elif chunk == ';' and self.entry.brcount <= 0:
+ self.dump_declaration(ln, self.entry.prototype)
+ self.reset_state(ln)
+ return
+ #
+ # We hit the end of the line while still in the declaration; put
+ # in a space to represent the newline.
+ #
+ self.entry.prototype += ' '
+
+ def process_proto(self, ln, line):
+ """STATE_PROTO: reading a function/whatever prototype."""
+
+ if doc_inline_oneline.search(line):
+ self.entry.begin_section(ln, doc_inline_oneline.group(1))
+ self.entry.add_text(doc_inline_oneline.group(2))
+ self.dump_section()
+
+ elif doc_inline_start.search(line):
+ self.state = state.INLINE_NAME
+
+ elif self.entry.decl_type == 'function':
+ self.process_proto_function(ln, line)
+
+ else:
+ self.process_proto_type(ln, line)
+
+ def process_docblock(self, ln, line):
+ """STATE_DOCBLOCK: within a DOC: block."""
+
+ if doc_end.search(line):
+ self.dump_section()
+ self.output_declaration("doc", self.entry.identifier)
+ self.reset_state(ln)
+
+ elif doc_content.search(line):
+ self.entry.add_text(doc_content.group(1))
+
+ def parse_export(self):
+ """
+ Parses EXPORT_SYMBOL* macros from a single Kernel source file.
+ """
+
+ export_table = set()
+
+ try:
+ with open(self.fname, "r", encoding="utf8",
+ errors="backslashreplace") as fp:
+
+ for line in fp:
+ self.process_export(export_table, line)
+
+ except IOError:
+ return None
+
+ return export_table
+
+ #
+ # The state/action table telling us which function to invoke in
+ # each state.
+ #
+ state_actions = {
+ state.NORMAL: process_normal,
+ state.NAME: process_name,
+ state.BODY: process_body,
+ state.DECLARATION: process_decl,
+ state.SPECIAL_SECTION: process_special,
+ state.INLINE_NAME: process_inline_name,
+ state.INLINE_TEXT: process_inline_text,
+ state.PROTO: process_proto,
+ state.DOCBLOCK: process_docblock,
+ }
+
+ def parse_kdoc(self):
+ """
+ Open and process each line of a C source file.
+ The parsing is controlled via a state machine, and the line is passed
+ to a different process function depending on the state. The process
+ function may update the state as needed.
+
+ Besides parsing kernel-doc tags, it also parses export symbols.
+ """
+
+ prev = ""
+ prev_ln = None
+ export_table = set()
+
+ try:
+ with open(self.fname, "r", encoding="utf8",
+ errors="backslashreplace") as fp:
+ for ln, line in enumerate(fp):
+
+ line = line.expandtabs().strip("\n")
+
+ # Group continuation lines on prototypes
+ if self.state == state.PROTO:
+ if line.endswith("\\"):
+ prev += line.rstrip("\\")
+ if not prev_ln:
+ prev_ln = ln
+ continue
+
+ if prev:
+ ln = prev_ln
+ line = prev + line
+ prev = ""
+ prev_ln = None
+
+ self.config.log.debug("%d %s: %s",
+ ln, state.name[self.state],
+ line)
+
+ # This is an optimization over the original script.
+ # There, when export_file was used for the same file,
+ # it was read twice. Here, we use the already-existing
+ # loop to parse exported symbols as well.
+ #
+ if (self.state != state.NORMAL) or \
+ not self.process_export(export_table, line):
+ # Hand this line to the appropriate state handler
+ self.state_actions[self.state](self, ln, line)
+
+ except OSError:
+ self.config.log.error(f"Error: Cannot open file {self.fname}")
+
+ return export_table, self.entries
diff --git a/scripts/lib/kdoc/kdoc_re.py b/scripts/lib/kdoc/kdoc_re.py
new file mode 100644
index 000000000000..612223e1e723
--- /dev/null
+++ b/scripts/lib/kdoc/kdoc_re.py
@@ -0,0 +1,270 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+# Copyright(c) 2025: Mauro Carvalho Chehab <mchehab@kernel.org>.
+
+"""
+Regular expression ancillary classes.
+
+Those help caching regular expressions and do matching for kernel-doc.
+"""
+
+import re
+
+# Local cache for regular expressions
+re_cache = {}
+
+
+class KernRe:
+ """
+ Helper class to simplify regex declaration and usage,
+
+ It calls re.compile for a given pattern. It also allows adding
+ regular expressions and define sub at class init time.
+
+ Regular expressions can be cached via an argument, helping to speedup
+ searches.
+ """
+
+ def _add_regex(self, string, flags):
+ """
+ Adds a new regex or re-use it from the cache.
+ """
+ self.regex = re_cache.get(string, None)
+ if not self.regex:
+ self.regex = re.compile(string, flags=flags)
+ if self.cache:
+ re_cache[string] = self.regex
+
+ def __init__(self, string, cache=True, flags=0):
+ """
+ Compile a regular expression and initialize internal vars.
+ """
+
+ self.cache = cache
+ self.last_match = None
+
+ self._add_regex(string, flags)
+
+ def __str__(self):
+ """
+ Return the regular expression pattern.
+ """
+ return self.regex.pattern
+
+ def __add__(self, other):
+ """
+ Allows adding two regular expressions into one.
+ """
+
+ return KernRe(str(self) + str(other), cache=self.cache or other.cache,
+ flags=self.regex.flags | other.regex.flags)
+
+ def match(self, string):
+ """
+ Handles a re.match storing its results
+ """
+
+ self.last_match = self.regex.match(string)
+ return self.last_match
+
+ def search(self, string):
+ """
+ Handles a re.search storing its results
+ """
+
+ self.last_match = self.regex.search(string)
+ return self.last_match
+
+ def findall(self, string):
+ """
+ Alias to re.findall
+ """
+
+ return self.regex.findall(string)
+
+ def split(self, string):
+ """
+ Alias to re.split
+ """
+
+ return self.regex.split(string)
+
+ def sub(self, sub, string, count=0):
+ """
+ Alias to re.sub
+ """
+
+ return self.regex.sub(sub, string, count=count)
+
+ def group(self, num):
+ """
+ Returns the group results of the last match
+ """
+
+ return self.last_match.group(num)
+
+
+class NestedMatch:
+ """
+ Finding nested delimiters is hard with regular expressions. It is
+ even harder on Python with its normal re module, as there are several
+ advanced regular expressions that are missing.
+
+ This is the case of this pattern:
+
+ '\\bSTRUCT_GROUP(\\(((?:(?>[^)(]+)|(?1))*)\\))[^;]*;'
+
+ which is used to properly match open/close parenthesis of the
+ string search STRUCT_GROUP(),
+
+ Add a class that counts pairs of delimiters, using it to match and
+ replace nested expressions.
+
+ The original approach was suggested by:
+ https://stackoverflow.com/questions/5454322/python-how-to-match-nested-parentheses-with-regex
+
+ Although I re-implemented it to make it more generic and match 3 types
+ of delimiters. The logic checks if delimiters are paired. If not, it
+ will ignore the search string.
+ """
+
+ # TODO: make NestedMatch handle multiple match groups
+ #
+ # Right now, regular expressions to match it are defined only up to
+ # the start delimiter, e.g.:
+ #
+ # \bSTRUCT_GROUP\(
+ #
+ # is similar to: STRUCT_GROUP\((.*)\)
+ # except that the content inside the match group is delimiter's aligned.
+ #
+ # The content inside parenthesis are converted into a single replace
+ # group (e.g. r`\1').
+ #
+ # It would be nice to change such definition to support multiple
+ # match groups, allowing a regex equivalent to.
+ #
+ # FOO\((.*), (.*), (.*)\)
+ #
+ # it is probably easier to define it not as a regular expression, but
+ # with some lexical definition like:
+ #
+ # FOO(arg1, arg2, arg3)
+
+ DELIMITER_PAIRS = {
+ '{': '}',
+ '(': ')',
+ '[': ']',
+ }
+
+ RE_DELIM = re.compile(r'[\{\}\[\]\(\)]')
+
+ def _search(self, regex, line):
+ """
+ Finds paired blocks for a regex that ends with a delimiter.
+
+ The suggestion of using finditer to match pairs came from:
+ https://stackoverflow.com/questions/5454322/python-how-to-match-nested-parentheses-with-regex
+ but I ended using a different implementation to align all three types
+ of delimiters and seek for an initial regular expression.
+
+ The algorithm seeks for open/close paired delimiters and place them
+ into a stack, yielding a start/stop position of each match when the
+ stack is zeroed.
+
+ The algorithm shoud work fine for properly paired lines, but will
+ silently ignore end delimiters that preceeds an start delimiter.
+ This should be OK for kernel-doc parser, as unaligned delimiters
+ would cause compilation errors. So, we don't need to rise exceptions
+ to cover such issues.
+ """
+
+ stack = []
+
+ for match_re in regex.finditer(line):
+ start = match_re.start()
+ offset = match_re.end()
+
+ d = line[offset - 1]
+ if d not in self.DELIMITER_PAIRS:
+ continue
+
+ end = self.DELIMITER_PAIRS[d]
+ stack.append(end)
+
+ for match in self.RE_DELIM.finditer(line[offset:]):
+ pos = match.start() + offset
+
+ d = line[pos]
+
+ if d in self.DELIMITER_PAIRS:
+ end = self.DELIMITER_PAIRS[d]
+
+ stack.append(end)
+ continue
+
+ # Does the end delimiter match what it is expected?
+ if stack and d == stack[-1]:
+ stack.pop()
+
+ if not stack:
+ yield start, offset, pos + 1
+ break
+
+ def search(self, regex, line):
+ """
+ This is similar to re.search:
+
+ It matches a regex that it is followed by a delimiter,
+ returning occurrences only if all delimiters are paired.
+ """
+
+ for t in self._search(regex, line):
+
+ yield line[t[0]:t[2]]
+
+ def sub(self, regex, sub, line, count=0):
+ """
+ This is similar to re.sub:
+
+ It matches a regex that it is followed by a delimiter,
+ replacing occurrences only if all delimiters are paired.
+
+ if r'\1' is used, it works just like re: it places there the
+ matched paired data with the delimiter stripped.
+
+ If count is different than zero, it will replace at most count
+ items.
+ """
+ out = ""
+
+ cur_pos = 0
+ n = 0
+
+ for start, end, pos in self._search(regex, line):
+ out += line[cur_pos:start]
+
+ # Value, ignoring start/end delimiters
+ value = line[end:pos - 1]
+
+ # replaces \1 at the sub string, if \1 is used there
+ new_sub = sub
+ new_sub = new_sub.replace(r'\1', value)
+
+ out += new_sub
+
+ # Drop end ';' if any
+ if line[pos] == ';':
+ pos += 1
+
+ cur_pos = pos
+ n += 1
+
+ if count and count >= n:
+ break
+
+ # Append the remaining string
+ l = len(line)
+ out += line[cur_pos:l]
+
+ return out