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Diffstat (limited to 'scripts/lib/abi/abi_regex.py')
| -rw-r--r-- | scripts/lib/abi/abi_regex.py | 234 |
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) |