scripts/qapi/common.py

   1 #
   2 # QAPI helper library
   3 #
   4 # Copyright IBM, Corp. 2011
   5 # Copyright (c) 2013-2018 Red Hat Inc.
   6 #
   7 # Authors:
   8 #  Anthony Liguori <aliguori@us.ibm.com>
   9 #  Markus Armbruster <armbru@redhat.com>
  10 #
  11 # This work is licensed under the terms of the GNU GPL, version 2.
  12 # See the COPYING file in the top-level directory.
  13
  14 import re
  15 from typing import (
  16     Any,
  17     Dict,
  18     Match,
  19     Optional,
  20     Union,
  21 )
  22
  23
  24 #: Magic string that gets removed along with all space to its right.
  25 EATSPACE = '\033EATSPACE.'
  26 POINTER_SUFFIX = ' *' + EATSPACE
  27
  28
  29 def camel_to_upper(value: str) -> str:
  30     """
  31     Converts CamelCase to CAMEL_CASE.
  32
  33     Examples::
  34
  35         ENUMName -> ENUM_NAME
  36         EnumName1 -> ENUM_NAME1
  37         ENUM_NAME -> ENUM_NAME
  38         ENUM_NAME1 -> ENUM_NAME1
  39         ENUM_Name2 -> ENUM_NAME2
  40         ENUM24_Name -> ENUM24_NAME
  41     """
  42     c_fun_str = c_name(value, False)
  43     if value.isupper():
  44         return c_fun_str
  45
  46     new_name = ''
  47     length = len(c_fun_str)
  48     for i in range(length):
  49         char = c_fun_str[i]
  50         # When char is upper case and no '_' appears before, do more checks
  51         if char.isupper() and (i > 0) and c_fun_str[i - 1] != '_':
  52             if i < length - 1 and c_fun_str[i + 1].islower():
  53                 new_name += '_'
  54             elif c_fun_str[i - 1].isdigit():
  55                 new_name += '_'
  56         new_name += char
  57     return new_name.lstrip('_').upper()
  58
  59
  60 def c_enum_const(type_name: str,
  61                  const_name: str,
  62                  prefix: Optional[str] = None) -> str:
  63     """
  64     Generate a C enumeration constant name.
  65
  66     :param type_name: The name of the enumeration.
  67     :param const_name: The name of this constant.
  68     :param prefix: Optional, prefix that overrides the type_name.
  69     """
  70     if prefix is not None:
  71         type_name = prefix
  72     return camel_to_upper(type_name) + '_' + c_name(const_name, False).upper()
  73
  74
  75 def c_name(name: str, protect: bool = True) -> str:
  76     """
  77     Map ``name`` to a valid C identifier.
  78
  79     Used for converting 'name' from a 'name':'type' qapi definition
  80     into a generated struct member, as well as converting type names
  81     into substrings of a generated C function name.
  82
  83     '__a.b_c' -> '__a_b_c', 'x-foo' -> 'x_foo'
  84     protect=True: 'int' -> 'q_int'; protect=False: 'int' -> 'int'
  85
  86     :param name: The name to map.
  87     :param protect: If true, avoid returning certain ticklish identifiers
  88                     (like C keywords) by prepending ``q_``.
  89     """
  90     # ANSI X3J11/88-090, 3.1.1
  91     c89_words = set(['auto', 'break', 'case', 'char', 'const', 'continue',
  92                      'default', 'do', 'double', 'else', 'enum', 'extern',
  93                      'float', 'for', 'goto', 'if', 'int', 'long', 'register',
  94                      'return', 'short', 'signed', 'sizeof', 'static',
  95                      'struct', 'switch', 'typedef', 'union', 'unsigned',
  96                      'void', 'volatile', 'while'])
  97     # ISO/IEC 9899:1999, 6.4.1
  98     c99_words = set(['inline', 'restrict', '_Bool', '_Complex', '_Imaginary'])
  99     # ISO/IEC 9899:2011, 6.4.1
 100     c11_words = set(['_Alignas', '_Alignof', '_Atomic', '_Generic',
 101                      '_Noreturn', '_Static_assert', '_Thread_local'])
 102     # GCC http://gcc.gnu.org/onlinedocs/gcc-4.7.1/gcc/C-Extensions.html
 103     # excluding _.*
 104     gcc_words = set(['asm', 'typeof'])
 105     # C++ ISO/IEC 14882:2003 2.11
 106     cpp_words = set(['bool', 'catch', 'class', 'const_cast', 'delete',
 107                      'dynamic_cast', 'explicit', 'false', 'friend', 'mutable',
 108                      'namespace', 'new', 'operator', 'private', 'protected',
 109                      'public', 'reinterpret_cast', 'static_cast', 'template',
 110                      'this', 'throw', 'true', 'try', 'typeid', 'typename',
 111                      'using', 'virtual', 'wchar_t',
 112                      # alternative representations
 113                      'and', 'and_eq', 'bitand', 'bitor', 'compl', 'not',
 114                      'not_eq', 'or', 'or_eq', 'xor', 'xor_eq'])
 115     # namespace pollution:
 116     polluted_words = set(['unix', 'errno', 'mips', 'sparc', 'i386'])
 117     name = re.sub(r'[^A-Za-z0-9_]', '_', name)
 118     if protect and (name in (c89_words | c99_words | c11_words | gcc_words
 119                              | cpp_words | polluted_words)
 120                     or name[0].isdigit()):
 121         return 'q_' + name
 122     return name
 123
 124
 125 class Indentation:
 126     """
 127     Indentation level management.
 128
 129     :param initial: Initial number of spaces, default 0.
 130     """
 131     def __init__(self, initial: int = 0) -> None:
 132         self._level = initial
 133
 134     def __int__(self) -> int:
 135         return self._level
 136
 137     def __repr__(self) -> str:
 138         return "{}({:d})".format(type(self).__name__, self._level)
 139
 140     def __str__(self) -> str:
 141         """Return the current indentation as a string of spaces."""
 142         return ' ' * self._level
 143
 144     def __bool__(self) -> bool:
 145         """True when there is a non-zero indentation."""
 146         return bool(self._level)
 147
 148     def increase(self, amount: int = 4) -> None:
 149         """Increase the indentation level by ``amount``, default 4."""
 150         self._level += amount
 151
 152     def decrease(self, amount: int = 4) -> None:
 153         """Decrease the indentation level by ``amount``, default 4."""
 154         if self._level < amount:
 155             raise ArithmeticError(
 156                 f"Can't remove {amount:d} spaces from {self!r}")
 157         self._level -= amount
 158
 159
 160 #: Global, current indent level for code generation.
 161 indent = Indentation()
 162
 163
 164 def cgen(code: str, **kwds: object) -> str:
 165     """
 166     Generate ``code`` with ``kwds`` interpolated.
 167
 168     Obey `indent`, and strip `EATSPACE`.
 169     """
 170     raw = code % kwds
 171     if indent:
 172         raw = re.sub(r'^(?!(#|$))', str(indent), raw, flags=re.MULTILINE)
 173     return re.sub(re.escape(EATSPACE) + r' *', '', raw)
 174
 175
 176 def mcgen(code: str, **kwds: object) -> str:
 177     if code[0] == '\n':
 178         code = code[1:]
 179     return cgen(code, **kwds)
 180
 181
 182 def c_fname(filename: str) -> str:
 183     return re.sub(r'[^A-Za-z0-9_]', '_', filename)
 184
 185
 186 def guardstart(name: str) -> str:
 187     return mcgen('''
 188 #ifndef %(name)s
 189 #define %(name)s
 190
 191 ''',
 192                  name=c_fname(name).upper())
 193
 194
 195 def guardend(name: str) -> str:
 196     return mcgen('''
 197
 198 #endif /* %(name)s */
 199 ''',
 200                  name=c_fname(name).upper())
 201
 202
 203 def cgen_ifcond(ifcond: Union[str, Dict[str, Any]]) -> str:
 204     if not ifcond:
 205         return ''
 206     if isinstance(ifcond, str):
 207         return ifcond
 208
 209     oper, operands = next(iter(ifcond.items()))
 210     oper = {'all': '&&', 'any': '||'}[oper]
 211     operands = [cgen_ifcond(o) for o in operands]
 212     return '(' + (') ' + oper + ' (').join(operands) + ')'
 213
 214
 215 def docgen_ifcond(ifcond: Union[str, Dict[str, Any]]) -> str:
 216     # TODO Doc generated for conditions needs polish
 217     if not ifcond:
 218         return ''
 219     if isinstance(ifcond, str):
 220         return ifcond
 221
 222     oper, operands = next(iter(ifcond.items()))
 223     oper = {'all': ' and ', 'any': ' or '}[oper]
 224     operands = [docgen_ifcond(o) for o in operands]
 225     return '(' + oper.join(operands) + ')'
 226
 227
 228 def gen_if(cond: str) -> str:
 229     if not cond:
 230         return ''
 231     return mcgen('''
 232 #if %(cond)s
 233 ''', cond=cond)
 234
 235
 236 def gen_endif(cond: str) -> str:
 237     if not cond:
 238         return ''
 239     return mcgen('''
 240 #endif /* %(cond)s */
 241 ''', cond=cond)
 242
 243
 244 def must_match(pattern: str, string: str) -> Match[str]:
 245     match = re.match(pattern, string)
 246     assert match is not None
 247     return match