Merge branch 'mauro' into docs-mw

Mauro says:

This series replace get_abi.pl with a Python version.

I originally started it due to some issues I noticed when searching for
ABI symbols. While I could just go ahead and fix the already existing
script, I noticed that the script maintainance didn't have much care over
all those years, probably because it is easier to find Python programmers
those days.

Also, the code is complex and was not using modules or classes and
were using lots of global variables.

So, I decided to rewrite it in Python. I started with a manual conversion
for each function. Yet, to avoid future maintainership issues, I opted to
divide the main code on three classes, each on a sepaparate file.

Just like the original RFC, I opted to keep the Sphinx kernel-abi module
on three different phases:

- call get_abi.py as an exec file;
- import AbiParser on a minimal integration scenario;
- cleanup the code to avoid needing to parse line numbers from the text.

This way, if something goes wrong, it would be easier to just revert any
offending patches, It also provides a better rationale about what each
logical change is doing.

The initial patches on this series do some preparation work and
cleans some ABI symbol bugs that lack ":" delimiter.

1 files changed, 234 insertions, 0 deletions

diff --git a/scripts/lib/abi/abi_regex.py b/scripts/lib/abi/abi_regex.py
new file mode 100644
index 000000000000..8a57846cbc69
--- /dev/null
+++ b/scripts/lib/abi/abi_regex.py
@@ -0,0 +1,234 @@
+#!/usr/bin/env python3
+# xxpylint: disable=R0903
+# Copyright(c) 2025: Mauro Carvalho Chehab <mchehab@kernel.org>.
+# SPDX-License-Identifier: GPL-2.0
+
+"""
+Convert ABI what into regular expressions
+"""
+
+import re
+import sys
+
+from pprint import pformat
+
+from abi_parser import AbiParser
+from helpers import AbiDebug
+
+class AbiRegex(AbiParser):
+    """Extends AbiParser to search ABI nodes with regular expressions"""
+
+    # Escape only ASCII visible characters
+    escape_symbols = r"([\x21-\x29\x2b-\x2d\x3a-\x40\x5c\x60\x7b-\x7e])"
+    leave_others = "others"
+
+    # Tuples with regular expressions to be compiled and replacement data
+    re_whats = [
+        # Drop escape characters that might exist
+        (re.compile("\\\\"), ""),
+
+        # Temporarily escape dot characters
+        (re.compile(r"\."),  "\xf6"),
+
+        # Temporarily change [0-9]+ type of patterns
+        (re.compile(r"\[0\-9\]\+"),  "\xff"),
+
+        # Temporarily change [\d+-\d+] type of patterns
+        (re.compile(r"\[0\-\d+\]"),  "\xff"),
+        (re.compile(r"\[0:\d+\]"),  "\xff"),
+        (re.compile(r"\[(\d+)\]"),  "\xf4\\\\d+\xf5"),
+
+        # Temporarily change [0-9] type of patterns
+        (re.compile(r"\[(\d)\-(\d)\]"),  "\xf4\1-\2\xf5"),
+
+        # Handle multiple option patterns
+        (re.compile(r"[\{\<\[]([\w_]+)(?:[,|]+([\w_]+)){1,}[\}\>\]]"), r"(\1|\2)"),
+
+        # Handle wildcards
+        (re.compile(r"([^\/])\*"), "\\1\\\\w\xf7"),
+        (re.compile(r"/\*/"), "/.*/"),
+        (re.compile(r"/\xf6\xf6\xf6"), "/.*"),
+        (re.compile(r"\<[^\>]+\>"), "\\\\w\xf7"),
+        (re.compile(r"\{[^\}]+\}"), "\\\\w\xf7"),
+        (re.compile(r"\[[^\]]+\]"), "\\\\w\xf7"),
+
+        (re.compile(r"XX+"), "\\\\w\xf7"),
+        (re.compile(r"([^A-Z])[XYZ]([^A-Z])"), "\\1\\\\w\xf7\\2"),
+        (re.compile(r"([^A-Z])[XYZ]$"), "\\1\\\\w\xf7"),
+        (re.compile(r"_[AB]_"), "_\\\\w\xf7_"),
+
+        # Recover [0-9] type of patterns
+        (re.compile(r"\xf4"), "["),
+        (re.compile(r"\xf5"),  "]"),
+
+        # Remove duplicated spaces
+        (re.compile(r"\s+"), r" "),
+
+        # Special case: drop comparison as in:
+        # What: foo = <something>
+        # (this happens on a few IIO definitions)
+        (re.compile(r"\s*\=.*$"), ""),
+
+        # Escape all other symbols
+        (re.compile(escape_symbols), r"\\\1"),
+        (re.compile(r"\\\\"), r"\\"),
+        (re.compile(r"\\([\[\]\(\)\|])"), r"\1"),
+        (re.compile(r"(\d+)\\(-\d+)"), r"\1\2"),
+
+        (re.compile(r"\xff"), r"\\d+"),
+
+        # Special case: IIO ABI which a parenthesis.
+        (re.compile(r"sqrt(.*)"), r"sqrt(.*)"),
+
+        # Simplify regexes with multiple .*
+        (re.compile(r"(?:\.\*){2,}"),  ""),
+
+        # Recover dot characters
+        (re.compile(r"\xf6"), "\\."),
+        # Recover plus characters
+        (re.compile(r"\xf7"), "+"),
+    ]
+    re_has_num = re.compile(r"\\d")
+
+    # Symbol name after escape_chars that are considered a devnode basename
+    re_symbol_name =  re.compile(r"(\w|\\[\.\-\:])+$")
+
+    # List of popular group names to be skipped to minimize regex group size
+    # Use AbiDebug.SUBGROUP_SIZE to detect those
+    skip_names = set(["devices", "hwmon"])
+
+    def regex_append(self, what, new):
+        """
+        Get a search group for a subset of regular expressions.
+
+        As ABI may have thousands of symbols, using a for to search all
+        regular expressions is at least O(n^2). When there are wildcards,
+        the complexity increases substantially, eventually becoming exponential.
+
+        To avoid spending too much time on them, use a logic to split
+        them into groups. The smaller the group, the better, as it would
+        mean that searches will be confined to a small number of regular
+        expressions.
+
+        The conversion to a regex subset is tricky, as we need something
+        that can be easily obtained from the sysfs symbol and from the
+        regular expression. So, we need to discard nodes that have
+        wildcards.
+
+        If it can't obtain a subgroup, place the regular expression inside
+        a special group (self.leave_others).
+        """
+
+        search_group = None
+
+        for search_group in reversed(new.split("/")):
+            if not search_group or search_group in self.skip_names:
+                continue
+            if self.re_symbol_name.match(search_group):
+                break
+
+        if not search_group:
+            search_group = self.leave_others
+
+        if self.debug & AbiDebug.SUBGROUP_MAP:
+            self.log.debug("%s: mapped as %s", what, search_group)
+
+        try:
+            if search_group not in self.regex_group:
+                self.regex_group[search_group] = []
+
+            self.regex_group[search_group].append(re.compile(new))
+            if self.search_string:
+                if what.find(self.search_string) >= 0:
+                    print(f"What: {what}")
+        except re.PatternError:
+            self.log.warning("Ignoring '%s' as it produced an invalid regex:\n"
+                             "           '%s'", what, new)
+
+    def get_regexes(self, what):
+        """
+        Given an ABI devnode, return a list of all regular expressions that
+        may match it, based on the sub-groups created by regex_append()
+        """
+
+        re_list = []
+
+        patches = what.split("/")
+        patches.reverse()
+        patches.append(self.leave_others)
+
+        for search_group in patches:
+            if search_group in self.regex_group:
+                re_list += self.regex_group[search_group]
+
+        return re_list
+
+    def __init__(self, *args, **kwargs):
+        """
+        Override init method to get verbose argument
+        """
+
+        self.regex_group = None
+        self.search_string = None
+        self.re_string = None
+
+        if "search_string" in kwargs:
+            self.search_string = kwargs.get("search_string")
+            del kwargs["search_string"]
+
+            if self.search_string:
+
+                try:
+                    self.re_string = re.compile(self.search_string)
+                except re.PatternError as e:
+                    msg = f"{self.search_string} is not a valid regular expression"
+                    raise ValueError(msg) from e
+
+        super().__init__(*args, **kwargs)
+
+    def parse_abi(self, *args, **kwargs):
+
+        super().parse_abi(*args, **kwargs)
+
+        self.regex_group = {}
+
+        print("Converting ABI What fields into regexes...", file=sys.stderr)
+
+        for t in sorted(self.data.items(), key=lambda x: x[0]):
+            v = t[1]
+            if v.get("type") == "File":
+                continue
+
+            v["regex"] = []
+
+            for what in v.get("what", []):
+                if not what.startswith("/sys"):
+                    continue
+
+                new = what
+                for r, s in self.re_whats:
+                    try:
+                        new = r.sub(s, new)
+                    except re.PatternError as e:
+                        # Help debugging troubles with new regexes
+                        raise re.PatternError(f"{e}\nwhile re.sub('{r.pattern}', {s}, str)") from e
+
+                v["regex"].append(new)
+
+                if self.debug & AbiDebug.REGEX:
+                    self.log.debug("%-90s <== %s", new, what)
+
+                # Store regex into a subgroup to speedup searches
+                self.regex_append(what, new)
+
+        if self.debug & AbiDebug.SUBGROUP_DICT:
+            self.log.debug("%s", pformat(self.regex_group))
+
+        if self.debug & AbiDebug.SUBGROUP_SIZE:
+            biggestd_keys = sorted(self.regex_group.keys(),
+                                   key= lambda k: len(self.regex_group[k]),
+                                   reverse=True)
+
+            print("Top regex subgroups:", file=sys.stderr)
+            for k in biggestd_keys[:10]:
+                print(f"{k} has {len(self.regex_group[k])} elements", file=sys.stderr)