xref: /linux/tools/lib/python/feat/parse_features.py (revision 37a93dd5c49b5fda807fd204edf2547c3493319c)
1#!/usr/bin/env python3
2# pylint: disable=R0902,R0911,R0912,R0914,R0915
3# Copyright(c) 2025: Mauro Carvalho Chehab <mchehab@kernel.org>.
4# SPDX-License-Identifier: GPL-2.0
5
6
7"""
8Library to parse the Linux Feature files and produce a ReST book.
9"""
10
11import os
12import re
13import sys
14
15from glob import iglob
16
17
18class ParseFeature:
19    """
20    Parses Documentation/features, allowing to generate ReST documentation
21    from it.
22    """
23
24    #: feature header string.
25    h_name = "Feature"
26
27    #: Kernel config header string.
28    h_kconfig = "Kconfig"
29
30    #: description header string.
31    h_description = "Description"
32
33    #: subsystem header string.
34    h_subsys = "Subsystem"
35
36    #: status header string.
37    h_status = "Status"
38
39    #: architecture header string.
40    h_arch = "Architecture"
41
42    #: Sort order for status. Others will be mapped at the end.
43    status_map = {
44        "ok":   0,
45        "TODO": 1,
46        "N/A":  2,
47        # The only missing status is "..", which was mapped as "---",
48        # as this is an special ReST cell value. Let it get the
49        # default order (99).
50    }
51
52    def __init__(self, prefix, debug=0, enable_fname=False):
53        """
54        Sets internal variables.
55        """
56
57        self.prefix = prefix
58        self.debug = debug
59        self.enable_fname = enable_fname
60
61        self.data = {}
62
63        # Initial maximum values use just the headers
64        self.max_size_name = len(self.h_name)
65        self.max_size_kconfig = len(self.h_kconfig)
66        self.max_size_description = len(self.h_description)
67        self.max_size_desc_word = 0
68        self.max_size_subsys = len(self.h_subsys)
69        self.max_size_status = len(self.h_status)
70        self.max_size_arch = len(self.h_arch)
71        self.max_size_arch_with_header = self.max_size_arch + self.max_size_arch
72        self.description_size = 1
73
74        self.msg = ""
75
76    def emit(self, msg="", end="\n"):
77        """Helper function to append a new message for feature output."""
78
79        self.msg += msg + end
80
81    def parse_error(self, fname, ln, msg, data=None):
82        """
83        Displays an error message, printing file name and line.
84        """
85
86        if ln:
87            fname += f"#{ln}"
88
89        print(f"Warning: file {fname}: {msg}", file=sys.stderr, end="")
90
91        if data:
92            data = data.rstrip()
93            print(f":\n\t{data}", file=sys.stderr)
94        else:
95            print("", file=sys.stderr)
96
97    def parse_feat_file(self, fname):
98        """Parses a single arch-support.txt feature file."""
99
100        if os.path.isdir(fname):
101            return
102
103        base = os.path.basename(fname)
104
105        if base != "arch-support.txt":
106            if self.debug:
107                print(f"ignoring {fname}", file=sys.stderr)
108            return
109
110        subsys = os.path.dirname(fname).split("/")[-2]
111        self.max_size_subsys = max(self.max_size_subsys, len(subsys))
112
113        feature_name = ""
114        kconfig = ""
115        description = ""
116        comments = ""
117        arch_table = {}
118
119        if self.debug > 1:
120            print(f"Opening {fname}", file=sys.stderr)
121
122        if self.enable_fname:
123            full_fname = os.path.abspath(fname)
124            self.emit(f".. FILE {full_fname}")
125
126        with open(fname, encoding="utf-8") as f:
127            for ln, line in enumerate(f, start=1):
128                line = line.strip()
129
130                match = re.match(r"^\#\s+Feature\s+name:\s*(.*\S)", line)
131                if match:
132                    feature_name = match.group(1)
133
134                    self.max_size_name = max(self.max_size_name,
135                                             len(feature_name))
136                    continue
137
138                match = re.match(r"^\#\s+Kconfig:\s*(.*\S)", line)
139                if match:
140                    kconfig = match.group(1)
141
142                    self.max_size_kconfig = max(self.max_size_kconfig,
143                                                len(kconfig))
144                    continue
145
146                match = re.match(r"^\#\s+description:\s*(.*\S)", line)
147                if match:
148                    description = match.group(1)
149
150                    self.max_size_description = max(self.max_size_description,
151                                                    len(description))
152
153                    words = re.split(r"\s+", line)[1:]
154                    for word in words:
155                        self.max_size_desc_word = max(self.max_size_desc_word,
156                                                        len(word))
157
158                    continue
159
160                if re.search(r"^\\s*$", line):
161                    continue
162
163                if re.match(r"^\s*\-+\s*$", line):
164                    continue
165
166                if re.search(r"^\s*\|\s*arch\s*\|\s*status\s*\|\s*$", line):
167                    continue
168
169                match = re.match(r"^\#\s*(.*)$", line)
170                if match:
171                    comments += match.group(1)
172                    continue
173
174                match = re.match(r"^\s*\|\s*(\S+):\s*\|\s*(\S+)\s*\|\s*$", line)
175                if match:
176                    arch = match.group(1)
177                    status = match.group(2)
178
179                    self.max_size_status = max(self.max_size_status,
180                                               len(status))
181                    self.max_size_arch = max(self.max_size_arch, len(arch))
182
183                    if status == "..":
184                        status = "---"
185
186                    arch_table[arch] = status
187
188                    continue
189
190                self.parse_error(fname, ln, "Line is invalid", line)
191
192        if not feature_name:
193            self.parse_error(fname, 0, "Feature name not found")
194            return
195        if not subsys:
196            self.parse_error(fname, 0, "Subsystem not found")
197            return
198        if not kconfig:
199            self.parse_error(fname, 0, "Kconfig not found")
200            return
201        if not description:
202            self.parse_error(fname, 0, "Description not found")
203            return
204        if not arch_table:
205            self.parse_error(fname, 0, "Architecture table not found")
206            return
207
208        self.data[feature_name] = {
209            "where": fname,
210            "subsys": subsys,
211            "kconfig": kconfig,
212            "description": description,
213            "comments": comments,
214            "table": arch_table,
215        }
216
217        self.max_size_arch_with_header = self.max_size_arch + len(self.h_arch)
218
219    def parse(self):
220        """Parses all arch-support.txt feature files inside self.prefix."""
221
222        path = os.path.expanduser(self.prefix)
223
224        if self.debug > 2:
225            print(f"Running parser for {path}")
226
227        example_path = os.path.join(path, "arch-support.txt")
228
229        for fname in iglob(os.path.join(path, "**"), recursive=True):
230            if fname != example_path:
231                self.parse_feat_file(fname)
232
233        return self.data
234
235    def output_arch_table(self, arch, feat=None):
236        """
237        Output feature(s) for a given architecture.
238        """
239
240        title = f"Feature status on {arch} architecture"
241
242        self.emit("=" * len(title))
243        self.emit(title)
244        self.emit("=" * len(title))
245        self.emit()
246
247        self.emit("=" * self.max_size_subsys + "  ", end="")
248        self.emit("=" * self.max_size_name + "  ", end="")
249        self.emit("=" * self.max_size_kconfig + "  ", end="")
250        self.emit("=" * self.max_size_status + "  ", end="")
251        self.emit("=" * self.max_size_description)
252
253        self.emit(f"{self.h_subsys:<{self.max_size_subsys}}  ", end="")
254        self.emit(f"{self.h_name:<{self.max_size_name}}  ", end="")
255        self.emit(f"{self.h_kconfig:<{self.max_size_kconfig}}  ", end="")
256        self.emit(f"{self.h_status:<{self.max_size_status}}  ", end="")
257        self.emit(f"{self.h_description:<{self.max_size_description}}")
258
259        self.emit("=" * self.max_size_subsys + "  ", end="")
260        self.emit("=" * self.max_size_name + "  ", end="")
261        self.emit("=" * self.max_size_kconfig + "  ", end="")
262        self.emit("=" * self.max_size_status + "  ", end="")
263        self.emit("=" * self.max_size_description)
264
265        sorted_features = sorted(self.data.keys(),
266                                 key=lambda x: (self.data[x]["subsys"],
267                                                x.lower()))
268
269        for name in sorted_features:
270            if feat and name != feat:
271                continue
272
273            arch_table = self.data[name]["table"]
274
275            if not arch in arch_table:
276                continue
277
278            self.emit(f"{self.data[name]['subsys']:<{self.max_size_subsys}}  ",
279                  end="")
280            self.emit(f"{name:<{self.max_size_name}}  ", end="")
281            self.emit(f"{self.data[name]['kconfig']:<{self.max_size_kconfig}}  ",
282                  end="")
283            self.emit(f"{arch_table[arch]:<{self.max_size_status}}  ",
284                  end="")
285            self.emit(f"{self.data[name]['description']}")
286
287        self.emit("=" * self.max_size_subsys + "  ", end="")
288        self.emit("=" * self.max_size_name + "  ", end="")
289        self.emit("=" * self.max_size_kconfig + "  ", end="")
290        self.emit("=" * self.max_size_status + "  ", end="")
291        self.emit("=" * self.max_size_description)
292
293        return self.msg
294
295    def output_feature(self, feat):
296        """
297        Output a feature on all architectures.
298        """
299
300        title = f"Feature {feat}"
301
302        self.emit("=" * len(title))
303        self.emit(title)
304        self.emit("=" * len(title))
305        self.emit()
306
307        if not feat in self.data:
308            return
309
310        if self.data[feat]["subsys"]:
311            self.emit(f":Subsystem: {self.data[feat]['subsys']}")
312        if self.data[feat]["kconfig"]:
313            self.emit(f":Kconfig: {self.data[feat]['kconfig']}")
314
315        desc = self.data[feat]["description"]
316        desc = desc[0].upper() + desc[1:]
317        desc = desc.rstrip(". \t")
318        self.emit(f"\n{desc}.\n")
319
320        com = self.data[feat]["comments"].strip()
321        if com:
322            self.emit("Comments")
323            self.emit("--------")
324            self.emit(f"\n{com}\n")
325
326        self.emit("=" * self.max_size_arch + "  ", end="")
327        self.emit("=" * self.max_size_status)
328
329        self.emit(f"{self.h_arch:<{self.max_size_arch}}  ", end="")
330        self.emit(f"{self.h_status:<{self.max_size_status}}")
331
332        self.emit("=" * self.max_size_arch + "  ", end="")
333        self.emit("=" * self.max_size_status)
334
335        arch_table = self.data[feat]["table"]
336        for arch in sorted(arch_table.keys()):
337            self.emit(f"{arch:<{self.max_size_arch}}  ", end="")
338            self.emit(f"{arch_table[arch]:<{self.max_size_status}}")
339
340        self.emit("=" * self.max_size_arch + "  ", end="")
341        self.emit("=" * self.max_size_status)
342
343        return self.msg
344
345    def matrix_lines(self, desc_size, max_size_status, header):
346        """
347        Helper function to split element tables at the output matrix.
348        """
349
350        if header:
351            ln_marker = "="
352        else:
353            ln_marker = "-"
354
355        self.emit("+" + ln_marker * self.max_size_name + "+", end="")
356        self.emit(ln_marker * desc_size, end="")
357        self.emit("+" + ln_marker * max_size_status + "+")
358
359    def output_matrix(self):
360        """
361        Generates a set of tables, groped by subsystem, containing
362        what's the feature state on each architecture.
363        """
364
365        title = "Feature status on all architectures"
366
367        self.emit("=" * len(title))
368        self.emit(title)
369        self.emit("=" * len(title))
370        self.emit()
371
372        desc_title = f"{self.h_kconfig} / {self.h_description}"
373
374        desc_size = self.max_size_kconfig + 4
375        if not self.description_size:
376            desc_size = max(self.max_size_description, desc_size)
377        else:
378            desc_size = max(self.description_size, desc_size)
379
380        desc_size = max(self.max_size_desc_word, desc_size, len(desc_title))
381
382        notcompat = "Not compatible"
383        self.max_size_status = max(self.max_size_status, len(notcompat))
384
385        min_status_size = self.max_size_status + self.max_size_arch + 4
386        max_size_status = max(min_status_size, self.max_size_status)
387
388        h_status_per_arch = "Status per architecture"
389        max_size_status = max(max_size_status, len(h_status_per_arch))
390
391        cur_subsys = None
392        for name in sorted(self.data.keys(),
393                           key=lambda x: (self.data[x]["subsys"], x.lower())):
394            if not cur_subsys or cur_subsys != self.data[name]["subsys"]:
395                if cur_subsys:
396                    self.emit()
397
398                cur_subsys = self.data[name]["subsys"]
399
400                title = f"Subsystem: {cur_subsys}"
401                self.emit(title)
402                self.emit("=" * len(title))
403                self.emit()
404
405                self.matrix_lines(desc_size, max_size_status, 0)
406
407                self.emit(f"|{self.h_name:<{self.max_size_name}}", end="")
408                self.emit(f"|{desc_title:<{desc_size}}", end="")
409                self.emit(f"|{h_status_per_arch:<{max_size_status}}|")
410
411                self.matrix_lines(desc_size, max_size_status, 1)
412
413            lines = []
414            descs = []
415            cur_status = ""
416            line = ""
417
418            arch_table = sorted(self.data[name]["table"].items(),
419                                key=lambda x: (self.status_map.get(x[1], 99),
420                                               x[0].lower()))
421
422            for arch, status in arch_table:
423                if status == "---":
424                    status = notcompat
425
426                if status != cur_status:
427                    if line != "":
428                        lines.append(line)
429                        line = ""
430                    line = f"- **{status}**: {arch}"
431                elif len(line) + len(arch) + 2 < max_size_status:
432                    line += f", {arch}"
433                else:
434                    lines.append(line)
435                    line = f"  {arch}"
436                cur_status = status
437
438            if line != "":
439                lines.append(line)
440
441            description = self.data[name]["description"]
442            while len(description) > desc_size:
443                desc_line = description[:desc_size]
444
445                last_space = desc_line.rfind(" ")
446                if last_space != -1:
447                    desc_line = desc_line[:last_space]
448                    descs.append(desc_line)
449                    description = description[last_space + 1:]
450                else:
451                    desc_line = desc_line[:-1]
452                    descs.append(desc_line + "\\")
453                    description = description[len(desc_line):]
454
455            if description:
456                descs.append(description)
457
458            while len(lines) < 2 + len(descs):
459                lines.append("")
460
461            for ln, line in enumerate(lines):
462                col = ["", ""]
463
464                if not ln:
465                    col[0] = name
466                    col[1] = f"``{self.data[name]['kconfig']}``"
467                else:
468                    if ln >= 2 and descs:
469                        col[1] = descs.pop(0)
470
471                self.emit(f"|{col[0]:<{self.max_size_name}}", end="")
472                self.emit(f"|{col[1]:<{desc_size}}", end="")
473                self.emit(f"|{line:<{max_size_status}}|")
474
475            self.matrix_lines(desc_size, max_size_status, 0)
476
477        return self.msg
478
479    def list_arch_features(self, arch, feat):
480        """
481        Print a matrix of kernel feature support for the chosen architecture.
482        """
483        self.emit("#")
484        self.emit(f"# Kernel feature support matrix of the '{arch}' architecture:")
485        self.emit("#")
486
487        # Sort by subsystem, then by feature name (case‑insensitive)
488        for name in sorted(self.data.keys(),
489                           key=lambda n: (self.data[n]["subsys"].lower(),
490                                          n.lower())):
491            if feat and name != feat:
492                continue
493
494            feature = self.data[name]
495            arch_table = feature["table"]
496            status = arch_table.get(arch, "")
497            status = " " * ((4 - len(status)) // 2) + status
498
499            self.emit(f"{feature['subsys']:>{self.max_size_subsys + 1}}/ ",
500                      end="")
501            self.emit(f"{name:<{self.max_size_name}}: ", end="")
502            self.emit(f"{status:<5}|   ", end="")
503            self.emit(f"{feature['kconfig']:>{self.max_size_kconfig}} ",
504                      end="")
505            self.emit(f"#  {feature['description']}")
506
507        return self.msg
508