qemu/scripts/qapi/common.py

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#
# QAPI helper library
#
# Copyright IBM, Corp. 2011
# Copyright (c) 2013-2018 Red Hat Inc.
#
# Authors:
# Anthony Liguori <aliguori@us.ibm.com>
qapi.py: Restructure lexer and parser The parser has a rather unorthodox structure: Until EOF: Read a section: Generator function get_expr() yields one section after the other, as a string. An unindented, non-empty line that isn't a comment starts a new section. Lexing: Split section into a list of tokens (strings), with help of generator function tokenize(). Parsing: Parse the first expression from the list of tokens, with parse(), throw away any remaining tokens. In parse_schema(): record value of an enum, union or struct key (if any) in the appropriate global table, append expression to the list of expressions. Return list of expressions. Known issues: (1) Indentation is significant, unlike in real JSON. (2) Neither lexer nor parser have any idea of source positions. Error reporting is hard, let's go shopping. (3) The one error we bother to detect, we "report" via raise. (4) The lexer silently ignores invalid characters. (5) If everything in a section gets ignored, the parser crashes. (6) The lexer treats a string containing a structural character exactly like the structural character. (7) Tokens trailing the first expression in a section are silently ignored. (8) The parser accepts any token in place of a colon. (9) The parser treats comma as optional. (10) parse() crashes on unexpected EOF. (11) parse_schema() crashes when a section's expression isn't a JSON object. Replace this piece of original art by a thoroughly unoriginal design. Takes care of (1), (2), (5), (6) and (7), and lays the groundwork for addressing the others. Generated source files remain unchanged. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1374939721-7876-4-git-send-email-armbru@redhat.com Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-07-27 19:41:55 +04:00
# Markus Armbruster <armbru@redhat.com>
#
# This work is licensed under the terms of the GNU GPL, version 2.
# See the COPYING file in the top-level directory.
import re
# ENUMName -> ENUM_NAME, EnumName1 -> ENUM_NAME1
# ENUM_NAME -> ENUM_NAME, ENUM_NAME1 -> ENUM_NAME1, ENUM_Name2 -> ENUM_NAME2
# ENUM24_Name -> ENUM24_NAME
def camel_to_upper(value):
c_fun_str = c_name(value, False)
if value.isupper():
return c_fun_str
new_name = ''
length = len(c_fun_str)
for i in range(length):
c = c_fun_str[i]
# When c is upper and no '_' appears before, do more checks
if c.isupper() and (i > 0) and c_fun_str[i - 1] != '_':
if i < length - 1 and c_fun_str[i + 1].islower():
new_name += '_'
elif c_fun_str[i - 1].isdigit():
new_name += '_'
new_name += c
return new_name.lstrip('_').upper()
def c_enum_const(type_name, const_name, prefix=None):
if prefix is not None:
type_name = prefix
qapi: Change munging of CamelCase enum values When munging enum values, the fact that we were passing the entire prefix + value through camel_to_upper() meant that enum values spelled with CamelCase could be turned into CAMEL_CASE. However, this provides a potential collision (both OneTwo and One-Two would munge into ONE_TWO) for enum types, when the same two names are valid side-by-side as QAPI member names. By changing the generation of enum constants to always be prefix + '_' + c_name(value, False).upper(), and ensuring that there are no case collisions (in the next patches), we no longer have to worry about names that would be distinct as QAPI members but collide as variant tag names, without having to think about what munging the heuristics in camel_to_upper() will actually perform on an enum value. Making the change will affect enums that did not follow coding conventions, using 'CamelCase' rather than desired 'lower-case'. Thankfully, there are only two culprits: InputButton and ErrorClass. We already tweaked ErrorClass to make it an alias of QapiErrorClass, where only the alias needs changing rather than the whole tree. So the bulk of this change is modifying INPUT_BUTTON_WHEEL_UP to the new INPUT_BUTTON_WHEELUP (and likewise for WHEELDOWN). That part of this commit may later need reverting if we rename the enum constants from 'WheelUp' to 'wheel-up' as part of moving x-input-send-event to a stable interface; but at least we have documentation bread crumbs in place to remind us (commit 513e7cd), and it matches the fact that SDL constants are also spelled SDL_BUTTON_WHEELUP. Suggested by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1447836791-369-27-git-send-email-eblake@redhat.com> [Commit message tweaked] Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-11-18 11:53:01 +03:00
return camel_to_upper(type_name) + '_' + c_name(const_name, False).upper()
c_name_trans = str.maketrans('.-', '__')
# Map @name to a valid C identifier.
# If @protect, avoid returning certain ticklish identifiers (like
# C keywords) by prepending 'q_'.
#
# Used for converting 'name' from a 'name':'type' qapi definition
# into a generated struct member, as well as converting type names
# into substrings of a generated C function name.
# '__a.b_c' -> '__a_b_c', 'x-foo' -> 'x_foo'
# protect=True: 'int' -> 'q_int'; protect=False: 'int' -> 'int'
def c_name(name, protect=True):
# ANSI X3J11/88-090, 3.1.1
c89_words = set(['auto', 'break', 'case', 'char', 'const', 'continue',
'default', 'do', 'double', 'else', 'enum', 'extern',
'float', 'for', 'goto', 'if', 'int', 'long', 'register',
'return', 'short', 'signed', 'sizeof', 'static',
'struct', 'switch', 'typedef', 'union', 'unsigned',
'void', 'volatile', 'while'])
# ISO/IEC 9899:1999, 6.4.1
c99_words = set(['inline', 'restrict', '_Bool', '_Complex', '_Imaginary'])
# ISO/IEC 9899:2011, 6.4.1
c11_words = set(['_Alignas', '_Alignof', '_Atomic', '_Generic',
'_Noreturn', '_Static_assert', '_Thread_local'])
# GCC http://gcc.gnu.org/onlinedocs/gcc-4.7.1/gcc/C-Extensions.html
# excluding _.*
gcc_words = set(['asm', 'typeof'])
# C++ ISO/IEC 14882:2003 2.11
cpp_words = set(['bool', 'catch', 'class', 'const_cast', 'delete',
'dynamic_cast', 'explicit', 'false', 'friend', 'mutable',
'namespace', 'new', 'operator', 'private', 'protected',
'public', 'reinterpret_cast', 'static_cast', 'template',
'this', 'throw', 'true', 'try', 'typeid', 'typename',
'using', 'virtual', 'wchar_t',
# alternative representations
'and', 'and_eq', 'bitand', 'bitor', 'compl', 'not',
'not_eq', 'or', 'or_eq', 'xor', 'xor_eq'])
# namespace pollution:
polluted_words = set(['unix', 'errno', 'mips', 'sparc', 'i386'])
name = name.translate(c_name_trans)
if protect and (name in c89_words | c99_words | c11_words | gcc_words
| cpp_words | polluted_words):
return 'q_' + name
return name
eatspace = '\033EATSPACE.'
pointer_suffix = ' *' + eatspace
def genindent(count):
ret = ''
for _ in range(count):
ret += ' '
return ret
indent_level = 0
def push_indent(indent_amount=4):
global indent_level
indent_level += indent_amount
def pop_indent(indent_amount=4):
global indent_level
indent_level -= indent_amount
# Generate @code with @kwds interpolated.
# Obey indent_level, and strip eatspace.
def cgen(code, **kwds):
raw = code % kwds
if indent_level:
indent = genindent(indent_level)
# re.subn() lacks flags support before Python 2.7, use re.compile()
raw = re.subn(re.compile(r'^(?!(#|$))', re.MULTILINE),
indent, raw)
raw = raw[0]
return re.sub(re.escape(eatspace) + r' *', '', raw)
def mcgen(code, **kwds):
if code[0] == '\n':
code = code[1:]
return cgen(code, **kwds)
def c_fname(filename):
return re.sub(r'[^A-Za-z0-9_]', '_', filename)
def guardstart(name):
return mcgen('''
#ifndef %(name)s
#define %(name)s
''',
name=c_fname(name).upper())
def guardend(name):
return mcgen('''
#endif /* %(name)s */
''',
name=c_fname(name).upper())
def gen_if(ifcond):
ret = ''
for ifc in ifcond:
ret += mcgen('''
#if %(cond)s
''', cond=ifc)
return ret
def gen_endif(ifcond):
ret = ''
for ifc in reversed(ifcond):
ret += mcgen('''
#endif /* %(cond)s */
''', cond=ifc)
return ret
def build_params(arg_type, boxed, extra=None):
ret = ''
sep = ''
if boxed:
assert arg_type
qapi: Implement boxed types for commands/events Turn on the ability to pass command and event arguments in a single boxed parameter, which must name a non-empty type (although the type can be a struct with all optional members). For structs, it makes it possible to pass a single qapi type instead of a breakout of all struct members (useful if the arguments are already in a struct or if the number of members is large); for other complex types, it is now possible to use a union or alternate as the data for a command or event. The empty type may be technically feasible if needed down the road, but it's easier to forbid it now and relax things to allow it later, than it is to allow it now and have to special case how the generated 'q_empty' type is handled (see commit 7ce106a9 for reasons why nothing is generated for the empty type). An alternate type is never considered empty, but now that a boxed type can be either an object or an alternate, we have to provide a trivial QAPISchemaAlternateType.is_empty(). The new call to arg_type.is_empty() during QAPISchemaCommand.check() requires that we first check the type in question; but there is no chance of introducing a cycle since objects do not refer back to commands. We still have a split in syntax checking between ad-hoc parsing up front (merely validates that 'boxed' has a sane value) and during .check() methods (if 'boxed' is set, then 'data' must name a non-empty user-defined type). Generated code is unchanged, as long as no client uses the new feature. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1468468228-27827-10-git-send-email-eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Test files renamed to *-boxed-*] Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-07-14 06:50:20 +03:00
ret += '%s arg' % arg_type.c_param_type()
sep = ', '
elif arg_type:
assert not arg_type.variants
for memb in arg_type.members:
ret += sep
sep = ', '
if memb.optional:
ret += 'bool has_%s, ' % c_name(memb.name)
ret += '%s %s' % (memb.type.c_param_type(),
c_name(memb.name))
if extra:
ret += sep + extra
return ret if ret else 'void'