cpython/Tools/c-analyzer/c_parser/declarations.py

296 lines
7.9 KiB
Python

import re
import shlex
import subprocess
from . import source
IDENTIFIER = r'(?:[a-zA-z]|_+[a-zA-Z0-9]\w*)'
TYPE_QUAL = r'(?:const|volatile)'
VAR_TYPE_SPEC = r'''(?:
void |
(?:
(?:(?:un)?signed\s+)?
(?:
char |
short |
int |
long |
long\s+int |
long\s+long
) |
) |
float |
double |
{IDENTIFIER} |
(?:struct|union)\s+{IDENTIFIER}
)'''
POINTER = rf'''(?:
(?:\s+const)?\s*[*]
)'''
#STRUCT = r'''(?:
# (?:struct|(struct\s+%s))\s*[{]
# [^}]*
# [}]
# )''' % (IDENTIFIER)
#UNION = r'''(?:
# (?:union|(union\s+%s))\s*[{]
# [^}]*
# [}]
# )''' % (IDENTIFIER)
#DECL_SPEC = rf'''(?:
# ({VAR_TYPE_SPEC}) |
# ({STRUCT}) |
# ({UNION})
# )'''
FUNC_START = rf'''(?:
(?:
(?:
extern |
static |
static\s+inline
)\s+
)?
#(?:const\s+)?
{VAR_TYPE_SPEC}
)'''
#GLOBAL_VAR_START = rf'''(?:
# (?:
# (?:
# extern |
# static
# )\s+
# )?
# (?:
# {TYPE_QUAL}
# (?:\s+{TYPE_QUAL})?
# )?\s+
# {VAR_TYPE_SPEC}
# )'''
GLOBAL_DECL_START_RE = re.compile(rf'''
^
(?:
({FUNC_START})
)
''', re.VERBOSE)
LOCAL_VAR_START = rf'''(?:
(?:
(?:
register |
static
)\s+
)?
(?:
(?:
{TYPE_QUAL}
(?:\s+{TYPE_QUAL})?
)\s+
)?
{VAR_TYPE_SPEC}
{POINTER}?
)'''
LOCAL_STMT_START_RE = re.compile(rf'''
^
(?:
({LOCAL_VAR_START})
)
''', re.VERBOSE)
def iter_global_declarations(lines):
"""Yield (decl, body) for each global declaration in the given lines.
For function definitions the header is reduced to one line and
the body is provided as-is. For other compound declarations (e.g.
struct) the entire declaration is reduced to one line and "body"
is None. Likewise for simple declarations (e.g. variables).
Declarations inside function bodies are ignored, though their text
is provided in the function body.
"""
# XXX Bail out upon bogus syntax.
lines = source.iter_clean_lines(lines)
for line in lines:
if not GLOBAL_DECL_START_RE.match(line):
continue
# We only need functions here, since we only need locals for now.
if line.endswith(';'):
continue
if line.endswith('{') and '(' not in line:
continue
# Capture the function.
# (assume no func is a one-liner)
decl = line
while '{' not in line: # assume no inline structs, etc.
try:
line = next(lines)
except StopIteration:
return
decl += ' ' + line
body, end = _extract_block(lines)
if end is None:
return
assert end == '}'
yield (f'{decl}\n{body}\n{end}', body)
def iter_local_statements(lines):
"""Yield (lines, blocks) for each statement in the given lines.
For simple statements, "blocks" is None and the statement is reduced
to a single line. For compound statements, "blocks" is a pair of
(header, body) for each block in the statement. The headers are
reduced to a single line each, but the bpdies are provided as-is.
"""
# XXX Bail out upon bogus syntax.
lines = source.iter_clean_lines(lines)
for line in lines:
if not LOCAL_STMT_START_RE.match(line):
continue
stmt = line
blocks = None
if not line.endswith(';'):
# XXX Support compound & multiline simple statements.
#blocks = []
continue
yield (stmt, blocks)
def _extract_block(lines):
end = None
depth = 1
body = []
for line in lines:
depth += line.count('{') - line.count('}')
if depth == 0:
end = line
break
body.append(line)
return '\n'.join(body), end
def parse_func(stmt, body):
"""Return (name, signature) for the given function definition."""
header, _, end = stmt.partition(body)
assert end.strip() == '}'
assert header.strip().endswith('{')
header, _, _= header.rpartition('{')
signature = ' '.join(header.strip().splitlines())
_, _, name = signature.split('(')[0].strip().rpartition(' ')
assert name
return name, signature
def parse_var(stmt):
"""Return (name, vartype) for the given variable declaration."""
stmt = stmt.rstrip(';')
m = LOCAL_STMT_START_RE.match(stmt)
assert m
vartype = m.group(0)
name = stmt[len(vartype):].partition('=')[0].strip()
if name.startswith('('):
name, _, after = name[1:].partition(')')
assert after
name = name.replace('*', '* ')
inside, _, name = name.strip().rpartition(' ')
vartype = f'{vartype} ({inside.strip()}){after}'
else:
name = name.replace('*', '* ')
before, _, name = name.rpartition(' ')
vartype = f'{vartype} {before}'
vartype = vartype.strip()
while ' ' in vartype:
vartype = vartype.replace(' ', ' ')
return name, vartype
def parse_compound(stmt, blocks):
"""Return (headers, bodies) for the given compound statement."""
# XXX Identify declarations inside compound statements
# (if/switch/for/while).
raise NotImplementedError
def iter_variables(filename, *,
_iter_source_lines=source.iter_lines,
_iter_global=iter_global_declarations,
_iter_local=iter_local_statements,
_parse_func=parse_func,
_parse_var=parse_var,
_parse_compound=parse_compound,
):
"""Yield (funcname, name, vartype) for every variable in the given file."""
lines = _iter_source_lines(filename)
for stmt, body in _iter_global(lines):
# At the file top-level we only have to worry about vars & funcs.
if not body:
name, vartype = _parse_var(stmt)
if name:
yield (None, name, vartype)
else:
funcname, _ = _parse_func(stmt, body)
localvars = _iter_locals(body,
_iter_statements=_iter_local,
_parse_var=_parse_var,
_parse_compound=_parse_compound,
)
for name, vartype in localvars:
yield (funcname, name, vartype)
def _iter_locals(lines, *,
_iter_statements=iter_local_statements,
_parse_var=parse_var,
_parse_compound=parse_compound,
):
compound = [lines]
while compound:
body = compound.pop(0)
bodylines = body.splitlines()
for stmt, blocks in _iter_statements(bodylines):
if not blocks:
name, vartype = _parse_var(stmt)
if name:
yield (name, vartype)
else:
headers, bodies = _parse_compound(stmt, blocks)
for header in headers:
for line in header:
name, vartype = _parse_var(line)
if name:
yield (name, vartype)
compound.extend(bodies)
def iter_all(dirnames):
"""Yield a Declaration for each one found.
If there are duplicates, due to preprocessor conditionals, then
they are checked to make sure they are the same.
"""
raise NotImplementedError
def iter_preprocessed(dirnames):
"""Yield a Declaration for each one found.
All source files are run through the preprocessor first.
"""
raise NotImplementedError