1 #! /usr/bin/env python3
2 """Generate coroutine wrappers for block subsystem.
4 The program parses one or several concatenated c files from stdin,
5 searches for functions with the 'co_wrapper' specifier
6 and generates corresponding wrappers on stdout.
8 Usage: block-coroutine-wrapper.py generated-file.c FILE.[ch]...
10 Copyright (c) 2020 Virtuozzo International GmbH.
12 This program is free software; you can redistribute it and/or modify
13 it under the terms of the GNU General Public License as published by
14 the Free Software Foundation; either version 2 of the License, or
15 (at your option) any later version.
17 This program is distributed in the hope that it will be useful,
18 but WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 GNU General Public License for more details.
22 You should have received a copy of the GNU General Public License
23 along with this program. If not, see <http://www.gnu.org/licenses/>.
28 from typing import Iterator
32 copyright = re.sub('^.*Copyright', 'Copyright', __doc__, flags=re.DOTALL)
33 copyright = re.sub('^(?=.)', ' * ', copyright.strip(), flags=re.MULTILINE)
34 copyright = re.sub('^$', ' *', copyright, flags=re.MULTILINE)
37 * File is generated by scripts/block-coroutine-wrapper.py
42 #include "qemu/osdep.h"
43 #include "block/coroutines.h"
44 #include "block/block-gen.h"
45 #include "block/block_int.h"\
50 param_re = re.compile(r'(?P<decl>'
52 r'(?P<name>[a-z][a-z0-9_]*)'
55 def __init__(self, param_decl: str) -> None:
56 m = self.param_re.match(param_decl.strip())
58 raise ValueError(f'Wrong parameter declaration: "{param_decl}"')
59 self.decl = m.group('decl')
60 self.type = m.group('type')
61 self.name = m.group('name')
65 def __init__(self, return_type: str, name: str, args: str,
66 variant: str) -> None:
67 self.return_type = return_type.strip()
68 self.name = name.strip()
69 self.struct_name = snake_to_camel(self.name)
70 self.args = [ParamDecl(arg.strip()) for arg in args.split(',')]
71 self.create_only_co = 'mixed' not in variant
73 subsystem, subname = self.name.split('_', 1)
74 self.co_name = f'{subsystem}_co_{subname}'
77 if t == 'BlockDriverState *':
78 ctx = 'bdrv_get_aio_context(bs)'
79 elif t == 'BdrvChild *':
80 ctx = 'bdrv_get_aio_context(child->bs)'
81 elif t == 'BlockBackend *':
82 ctx = 'blk_get_aio_context(blk)'
84 ctx = 'qemu_get_aio_context()'
87 def gen_list(self, format: str) -> str:
88 return ', '.join(format.format_map(arg.__dict__) for arg in self.args)
90 def gen_block(self, format: str) -> str:
91 return '\n'.join(format.format_map(arg.__dict__) for arg in self.args)
94 # Match wrappers declared with a co_wrapper mark
95 func_decl_re = re.compile(r'^int\s*co_wrapper'
96 r'(?P<variant>(_[a-z][a-z0-9_]*)?)\s*'
97 r'(?P<wrapper_name>[a-z][a-z0-9_]*)'
98 r'\((?P<args>[^)]*)\);$', re.MULTILINE)
101 def func_decl_iter(text: str) -> Iterator:
102 for m in func_decl_re.finditer(text):
103 yield FuncDecl(return_type='int',
104 name=m.group('wrapper_name'),
105 args=m.group('args'),
106 variant=m.group('variant'))
109 def snake_to_camel(func_name: str) -> str:
111 Convert underscore names like 'some_function_name' to camel-case like
114 words = func_name.split('_')
115 words = [w[0].upper() + w[1:] for w in words]
116 return ''.join(words)
119 def create_mixed_wrapper(func: FuncDecl) -> str:
121 Checks if we are already in coroutine
124 struct_name = func.struct_name
126 int {func.name}({ func.gen_list('{decl}') })
128 if (qemu_in_coroutine()) {{
129 return {name}({ func.gen_list('{name}') });
132 .poll_state.ctx = {func.ctx},
133 .poll_state.in_progress = true,
135 { func.gen_block(' .{name} = {name},') }
138 s.poll_state.co = qemu_coroutine_create({name}_entry, &s);
140 return bdrv_poll_co(&s.poll_state);
145 def create_co_wrapper(func: FuncDecl) -> str:
147 Assumes we are not in coroutine, and creates one
150 struct_name = func.struct_name
152 int {func.name}({ func.gen_list('{decl}') })
155 .poll_state.ctx = {func.ctx},
156 .poll_state.in_progress = true,
158 { func.gen_block(' .{name} = {name},') }
160 assert(!qemu_in_coroutine());
162 s.poll_state.co = qemu_coroutine_create({name}_entry, &s);
164 return bdrv_poll_co(&s.poll_state);
168 def gen_wrapper(func: FuncDecl) -> str:
169 assert not '_co_' in func.name
170 assert func.return_type == 'int'
173 struct_name = func.struct_name
175 creation_function = create_mixed_wrapper
176 if func.create_only_co:
177 creation_function = create_co_wrapper
181 * Wrappers for {name}
184 typedef struct {struct_name} {{
185 BdrvPollCo poll_state;
186 { func.gen_block(' {decl};') }
189 static void coroutine_fn {name}_entry(void *opaque)
191 {struct_name} *s = opaque;
193 s->poll_state.ret = {name}({ func.gen_list('s->{name}') });
194 s->poll_state.in_progress = false;
199 {creation_function(func)}"""
202 def gen_wrappers(input_code: str) -> str:
204 for func in func_decl_iter(input_code):
206 res += gen_wrapper(func)
211 if __name__ == '__main__':
212 if len(sys.argv) < 3:
213 exit(f'Usage: {sys.argv[0]} OUT_FILE.c IN_FILE.[ch]...')
215 with open(sys.argv[1], 'w', encoding='utf-8') as f_out:
216 f_out.write(gen_header())
217 for fname in sys.argv[2:]:
218 with open(fname, encoding='utf-8') as f_in:
219 f_out.write(gen_wrappers(f_in.read()))