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    "audio_drv_list",
30    "default_devices",
31    "docdir",
32    "fuzzing_engine",
33    "iasl",
34    "qemu_firmwarepath",
35    "qemu_suffix",
36    "smbd",
37    "sphinx_build",
38    "trace_file",
39}
40
41BUILTIN_OPTIONS = {
42    "strip",
43}
44
45LINE_WIDTH = 76
46
47
48# Convert the default value of an option to the string used in
49# the help message
50def value_to_help(value):
51    if isinstance(value, list):
52        return ",".join(value)
53    if isinstance(value, bool):
54        return "enabled" if value else "disabled"
55    return str(value)
56
57
58def wrap(left, text, indent):
59    spaces = " " * indent
60    if len(left) >= indent:
61        yield left
62        left = spaces
63    else:
64        left = (left + spaces)[0:indent]
65    yield from textwrap.wrap(
66        text, width=LINE_WIDTH, initial_indent=left, subsequent_indent=spaces
67    )
68
69
70def sh_print(line=""):
71    print('  printf "%s\\n"', shlex.quote(line))
72
73
74def help_line(left, opt, indent, long):
75    right = f'{opt["description"]}'
76    if long:
77        value = value_to_help(opt["value"])
78        if value != "auto":
79            right += f" [{value}]"
80    if "choices" in opt and long:
81        choices = "/".join(sorted(opt["choices"]))
82        right += f" (choices: {choices})"
83    for x in wrap("  " + left, right, indent):
84        sh_print(x)
85
86
87# Return whether the option (a dictionary) can be used with
88# arguments.  Booleans can never be used with arguments;
89# combos allow an argument only if they accept other values
90# than "auto", "enabled", and "disabled".
91def allow_arg(opt):
92    if opt["type"] == "boolean":
93        return False
94    if opt["type"] != "combo":
95        return True
96    return not (set(opt["choices"]) <= {"auto", "disabled", "enabled"})
97
98
99def filter_options(json):
100    if ":" in json["name"]:
101        return False
102    if json["section"] == "user":
103        return json["name"] not in SKIP_OPTIONS
104    else:
105        return json["name"] in BUILTIN_OPTIONS
106
107
108def load_options(json):
109    json = [x for x in json if filter_options(x)]
110    return sorted(json, key=lambda x: x["name"])
111
112
113def print_help(options):
114    print("meson_options_help() {")
115    for opt in options:
116        key = opt["name"].replace("_", "-")
117        # The first section includes options that have an arguments,
118        # and booleans (i.e., only one of enable/disable makes sense)
119        if opt["type"] == "boolean":
120            left = f"--disable-{key}" if opt["value"] else f"--enable-{key}"
121            help_line(left, opt, 27, False)
122        elif allow_arg(opt):
123            if opt["type"] == "combo" and "enabled" in opt["choices"]:
124                left = f"--enable-{key}[=CHOICE]"
125            else:
126                left = f"--enable-{key}=CHOICE"
127            help_line(left, opt, 27, True)
128
129    sh_print()
130    sh_print("Optional features, enabled with --enable-FEATURE and")
131    sh_print("disabled with --disable-FEATURE, default is enabled if available")
132    sh_print("(unless built with --without-default-features):")
133    sh_print()
134    for opt in options:
135        key = opt["name"].replace("_", "-")
136        if opt["type"] != "boolean" and not allow_arg(opt):
137            help_line(key, opt, 18, False)
138    print("}")
139
140
141def print_parse(options):
142    print("_meson_option_parse() {")
143    print("  case $1 in")
144    for opt in options:
145        key = opt["name"].replace("_", "-")
146        name = opt["name"]
147        if opt["type"] == "boolean":
148            print(f'    --enable-{key}) printf "%s" -D{name}=true ;;')
149            print(f'    --disable-{key}) printf "%s" -D{name}=false ;;')
150        else:
151            if opt["type"] == "combo" and "enabled" in opt["choices"]:
152                print(f'    --enable-{key}) printf "%s" -D{name}=enabled ;;')
153            if opt["type"] == "combo" and "disabled" in opt["choices"]:
154                print(f'    --disable-{key}) printf "%s" -D{name}=disabled ;;')
155            if allow_arg(opt):
156                print(f'    --enable-{key}=*) quote_sh "-D{name}=$2" ;;')
157    print("    *) return 1 ;;")
158    print("  esac")
159    print("}")
160
161
162options = load_options(json.load(sys.stdin))
163print("# This file is generated by meson-buildoptions.py, do not edit!")
164print_help(options)
165print_parse(options)
166