xref: /qemu/scripts/meson-buildoptions.py (revision 76eb88b1) 
1#! /usr/bin/env python3
2
3# Generate configure command line options handling code, based on Meson's
4# user build options introspection data
5#
6# Copyright (C) 2021 Red Hat, Inc.
7#
8# Author: Paolo Bonzini <pbonzini@redhat.com>
9#
10# This program is free software; you can redistribute it and/or modify
11# it under the terms of the GNU General Public License as published by
12# the Free Software Foundation; either version 2, or (at your option)
13# any later version.
14#
15# This program is distributed in the hope that it will be useful,
16# but WITHOUT ANY WARRANTY; without even the implied warranty of
17# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18# GNU General Public License for more details.
19#
20# You should have received a copy of the GNU General Public License
21# along with this program.  If not, see <https://www.gnu.org/licenses/>.
22
23import json
24import textwrap
25import shlex
26import sys
27
28SKIP_OPTIONS = {
29    "default_devices",
30    "fuzzing_engine",
31    "qemu_suffix",
32    "smbd",
33}
34
35OPTION_NAMES = {
36    "b_coverage": "gcov",
37    "b_lto": "lto",
38    "malloc": "enable-malloc",
39    "pkgversion": "with-pkgversion",
40    "qemu_firmwarepath": "firmwarepath",
41    "trace_backends": "enable-trace-backends",
42    "trace_file": "with-trace-file",
43}
44
45BUILTIN_OPTIONS = {
46    "b_coverage",
47    "b_lto",
48    "datadir",
49    "includedir",
50    "libdir",
51    "libexecdir",
52    "localedir",
53    "localstatedir",
54    "mandir",
55    "strip",
56    "sysconfdir",
57}
58
59LINE_WIDTH = 76
60
61
62# Convert the default value of an option to the string used in
63# the help message
64def value_to_help(value):
65    if isinstance(value, list):
66        return ",".join(value)
67    if isinstance(value, bool):
68        return "enabled" if value else "disabled"
69    return str(value)
70
71
72def wrap(left, text, indent):
73    spaces = " " * indent
74    if len(left) >= indent:
75        yield left
76        left = spaces
77    else:
78        left = (left + spaces)[0:indent]
79    yield from textwrap.wrap(
80        text, width=LINE_WIDTH, initial_indent=left, subsequent_indent=spaces
81    )
82
83
84def sh_print(line=""):
85    print('  printf "%s\\n"', shlex.quote(line))
86
87
88def help_line(left, opt, indent, long):
89    right = f'{opt["description"]}'
90    if long:
91        value = value_to_help(opt["value"])
92        if value != "auto" and value != "":
93            right += f" [{value}]"
94    if "choices" in opt and long:
95        choices = "/".join(sorted(opt["choices"]))
96        right += f" (choices: {choices})"
97    for x in wrap("  " + left, right, indent):
98        sh_print(x)
99
100
101# Return whether the option (a dictionary) can be used with
102# arguments.  Booleans can never be used with arguments;
103# combos allow an argument only if they accept other values
104# than "auto", "enabled", and "disabled".
105def allow_arg(opt):
106    if opt["type"] == "boolean":
107        return False
108    if opt["type"] != "combo":
109        return True
110    return not (set(opt["choices"]) <= {"auto", "disabled", "enabled"})
111
112
113# Return whether the option (a dictionary) can be used without
114# arguments.  Booleans can only be used without arguments;
115# combos require an argument if they accept neither "enabled"
116# nor "disabled"
117def require_arg(opt):
118    if opt["type"] == "boolean":
119        return False
120    if opt["type"] != "combo":
121        return True
122    return not ({"enabled", "disabled"}.intersection(opt["choices"]))
123
124
125def filter_options(json):
126    if ":" in json["name"]:
127        return False
128    if json["section"] == "user":
129        return json["name"] not in SKIP_OPTIONS
130    else:
131        return json["name"] in BUILTIN_OPTIONS
132
133
134def load_options(json):
135    json = [x for x in json if filter_options(x)]
136    return sorted(json, key=lambda x: x["name"])
137
138
139def cli_option(opt):
140    name = opt["name"]
141    if name in OPTION_NAMES:
142        return OPTION_NAMES[name]
143    return name.replace("_", "-")
144
145
146def cli_help_key(opt):
147    key = cli_option(opt)
148    if require_arg(opt):
149        return key
150    if opt["type"] == "boolean" and opt["value"]:
151        return f"disable-{key}"
152    return f"enable-{key}"
153
154
155def cli_metavar(opt):
156    if opt["type"] == "string":
157        return "VALUE"
158    if opt["type"] == "array":
159        return "CHOICES" if "choices" in opt else "VALUES"
160    return "CHOICE"
161
162
163def print_help(options):
164    print("meson_options_help() {")
165    for opt in sorted(options, key=cli_help_key):
166        key = cli_help_key(opt)
167        # The first section includes options that have an arguments,
168        # and booleans (i.e., only one of enable/disable makes sense)
169        if require_arg(opt):
170            metavar = cli_metavar(opt)
171            left = f"--{key}={metavar}"
172            help_line(left, opt, 27, True)
173        elif opt["type"] == "boolean":
174            left = f"--{key}"
175            help_line(left, opt, 27, False)
176        elif allow_arg(opt):
177            if opt["type"] == "combo" and "enabled" in opt["choices"]:
178                left = f"--{key}[=CHOICE]"
179            else:
180                left = f"--{key}=CHOICE"
181            help_line(left, opt, 27, True)
182
183    sh_print()
184    sh_print("Optional features, enabled with --enable-FEATURE and")
185    sh_print("disabled with --disable-FEATURE, default is enabled if available")
186    sh_print("(unless built with --without-default-features):")
187    sh_print()
188    for opt in options:
189        key = opt["name"].replace("_", "-")
190        if opt["type"] != "boolean" and not allow_arg(opt):
191            help_line(key, opt, 18, False)
192    print("}")
193
194
195def print_parse(options):
196    print("_meson_option_parse() {")
197    print("  case $1 in")
198    for opt in options:
199        key = cli_option(opt)
200        name = opt["name"]
201        if require_arg(opt):
202            if opt["type"] == "array" and not "choices" in opt:
203                print(f'    --{key}=*) quote_sh "-D{name}=$(meson_option_build_array $2)" ;;')
204            else:
205                print(f'    --{key}=*) quote_sh "-D{name}=$2" ;;')
206        elif opt["type"] == "boolean":
207            print(f'    --enable-{key}) printf "%s" -D{name}=true ;;')
208            print(f'    --disable-{key}) printf "%s" -D{name}=false ;;')
209        else:
210            if opt["type"] == "combo" and "enabled" in opt["choices"]:
211                print(f'    --enable-{key}) printf "%s" -D{name}=enabled ;;')
212            if opt["type"] == "combo" and "disabled" in opt["choices"]:
213                print(f'    --disable-{key}) printf "%s" -D{name}=disabled ;;')
214            if allow_arg(opt):
215                print(f'    --enable-{key}=*) quote_sh "-D{name}=$2" ;;')
216    print("    *) return 1 ;;")
217    print("  esac")
218    print("}")
219
220
221options = load_options(json.load(sys.stdin))
222print("# This file is generated by meson-buildoptions.py, do not edit!")
223print_help(options)
224print_parse(options)
225