1#!/usr/bin/env python3
2#
3# Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
4#
5# SPDX-License-Identifier: BSD-2-Clause or GPL-2.0-only
6#
7
8# seL4 System Call ID Generator
9# ==============================
10
11from __future__ import print_function
12from jinja2 import Environment, BaseLoader
13import argparse
14import re
15import sys
16import xml.dom.minidom
17import pkg_resources
18# We require jinja2 to be at least version 2.10 as we use the 'namespace' feature from
19# that version
20pkg_resources.require("jinja2>=2.10")
21
22
23COMMON_HEADER = """
24/* This header was generated by kernel/tools/syscall_header_gen.py.
25 *
26 * To add a system call number, edit kernel/include/api/syscall.xml
27 *
28 */"""
29
30KERNEL_HEADER_TEMPLATE = """/*
31 * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
32 *
33 * SPDX-License-Identifier: GPL-2.0-only
34 */
35
36""" + COMMON_HEADER + """
37#ifndef __ARCH_API_SYSCALL_H
38#define __ARCH_API_SYSCALL_H
39
40#ifdef __ASSEMBLER__
41
42/* System Calls */
43{%- set ns = namespace(syscall_number=-1) -%}
44{%- for condition, list in assembler  -%}
45    {%- for syscall in list %}
46#define SYSCALL_{{upper(syscall)}} ({{ns.syscall_number}})
47    {%- set ns.syscall_number = ns.syscall_number -1 -%}
48    {%- endfor  %}
49{%- endfor  %}
50
51#endif
52
53#define SYSCALL_MAX (-1)
54#define SYSCALL_MIN ({{ns.syscall_number+ 1}})
55
56#ifndef __ASSEMBLER__
57
58enum syscall {
59{%- set ns.syscall_number = -1 -%}
60{% for condition, list in enum %}
61   {%- if condition | length > 0 %}
62#if {{condition}}
63   {%- endif %}
64   {%- for syscall in list %}
65    Sys{{syscall}} = {{ns.syscall_number}},
66    {%- set ns.syscall_number = ns.syscall_number -1 -%}
67   {%- endfor %}
68   {%- if condition | length > 0 %}
69#endif /* {{condition}} */
70   {%- endif %}
71{%- endfor %}
72};
73typedef word_t syscall_t;
74
75/* System call names */
76#ifdef CONFIG_DEBUG_BUILD
77static char *syscall_names[] UNUSED = {
78{%- set ns.syscall_number = 1 -%}
79{%- for condition, list in assembler %}
80   {%- for syscall in list %}
81         [{{ns.syscall_number}}] = "{{syscall}}",
82        {%- set ns.syscall_number = ns.syscall_number +1 -%}
83   {%- endfor %}
84{%- endfor %}
85};
86#endif /* CONFIG_DEBUG_BUILD */
87#endif
88
89#endif /* __ARCH_API_SYSCALL_H */
90
91"""
92
93LIBSEL4_HEADER_TEMPLATE = """/*
94 * Copyright 2020, Data61, CSIRO (ABN 41 687 119 230)
95 *
96 * SPDX-License-Identifier: BSD-2-Clause
97 */
98
99""" + COMMON_HEADER + """
100#ifndef __LIBSEL4_SYSCALL_H
101#define __LIBSEL4_SYSCALL_H
102
103#include <autoconf.h>
104
105typedef enum {
106{%- set ns = namespace(syscall_number=-1) -%}
107{%- for condition, list in enum %}
108   {%- if condition | length > 0 %}
109#if {{condition}}
110   {%- endif %}
111   {%- for syscall in list %}
112    seL4_Sys{{syscall}} = {{ns.syscall_number}},
113    {%- set ns.syscall_number = ns.syscall_number - 1 -%}
114   {%- endfor %}
115   {%- if condition | length > 0 %}
116#endif /* {{condition}} */
117   {%- endif %}
118{%- endfor %}
119    SEL4_FORCE_LONG_ENUM(seL4_Syscall_ID)
120} seL4_Syscall_ID;
121
122#endif /* __ARCH_API_SYSCALL_H */
123
124"""
125
126
127def parse_args():
128    parser = argparse.ArgumentParser(description="""Generate seL4 syscall API constants
129                                                    and associated header files""")
130    parser.add_argument('--xml', type=argparse.FileType('r'),
131                        help='Name of xml file with syscall name definitions', required=True)
132    parser.add_argument('--kernel_header', type=argparse.FileType('w'),
133                        help='Name of file to generate for kernel')
134    parser.add_argument('--libsel4_header', type=argparse.FileType('w'),
135                        help='Name of file to generate for libsel4')
136    parser.add_argument('--mcs', action='store_true',
137                        help='Generate MCS api')
138
139    result = parser.parse_args()
140
141    if result.kernel_header is None and result.libsel4_header is None:
142        print("Error: must provide either kernel_header or libsel4_header",
143              file=sys.stderr)
144        parser.print_help()
145        exit(-1)
146
147    return result
148
149
150def parse_syscall_list(element):
151    syscalls = []
152    for config in element.getElementsByTagName("config"):
153        config_condition = config.getAttribute("condition")
154        config_syscalls = []
155        for syscall in config.getElementsByTagName("syscall"):
156            name = str(syscall.getAttribute("name"))
157            config_syscalls.append(name)
158        syscalls.append((config_condition, config_syscalls))
159
160    # sanity check
161    assert len(syscalls) != 0
162
163    return syscalls
164
165
166def parse_xml(xml_file, mcs):
167    # first check if the file is valid xml
168    try:
169        doc = xml.dom.minidom.parse(xml_file)
170    except:
171        print("Error: invalid xml file.", file=sys.stderr)
172        sys.exit(-1)
173
174    tag = "api-mcs" if mcs else "api-master"
175    api = doc.getElementsByTagName(tag)
176    if len(api) != 1:
177        print("Error: malformed xml. Only one api element allowed",
178              file=sys.stderr)
179        sys.exit(-1)
180
181    configs = api[0].getElementsByTagName("config")
182    if len(configs) != 1:
183        print("Error: api element only supports 1 config element",
184              file=sys.stderr)
185        sys.exit(-1)
186
187    if len(configs[0].getAttribute("name")) != 0:
188        print("Error: api element config only supports an empty name",
189              file=sys.stderr)
190        sys.exit(-1)
191
192    # debug elements are optional
193    debug = doc.getElementsByTagName("debug")
194    if len(debug) != 1:
195        debug_element = None
196    else:
197        debug_element = debug[0]
198
199    api_elements = parse_syscall_list(api[0])
200    debug = parse_syscall_list(debug_element)
201
202    return (api_elements, debug)
203
204
205def convert_to_assembler_format(s):
206    words = re.findall('[A-Z][A-Z]?[^A-Z]*', s)
207    return '_'.join(words).upper()
208
209
210def generate_kernel_file(kernel_header, api, debug):
211    template = Environment(loader=BaseLoader, trim_blocks=False,
212                           lstrip_blocks=False).from_string(KERNEL_HEADER_TEMPLATE)
213    data = template.render({'assembler': api, 'enum': api + debug,
214                            'upper': convert_to_assembler_format})
215    kernel_header.write(data)
216
217
218def generate_libsel4_file(libsel4_header, syscalls):
219    template = Environment(loader=BaseLoader, trim_blocks=False,
220                           lstrip_blocks=False).from_string(LIBSEL4_HEADER_TEMPLATE)
221    data = template.render({'enum': syscalls})
222    libsel4_header.write(data)
223
224
225if __name__ == "__main__":
226    args = parse_args()
227
228    (api, debug) = parse_xml(args.xml, args.mcs)
229    args.xml.close()
230
231    if (args.kernel_header is not None):
232        generate_kernel_file(args.kernel_header, api, debug)
233        args.kernel_header.close()
234
235    if (args.libsel4_header is not None):
236        generate_libsel4_file(args.libsel4_header, api + debug)
237        args.libsel4_header.close()
238