Add qemu 2.4.0

Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>

1 files changed, 1074 insertions, 0 deletions

diff --git a/qemu/scripts/qapi.py b/qemu/scripts/qapi.py
new file mode 100644
index 000000000..06d7fc284
--- /dev/null
+++ b/qemu/scripts/qapi.py
@@ -0,0 +1,1074 @@
+#
+# QAPI helper library
+#
+# Copyright IBM, Corp. 2011
+# Copyright (c) 2013-2015 Red Hat Inc.
+#
+# Authors:
+#  Anthony Liguori <aliguori@us.ibm.com>
+#  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
+from ordereddict import OrderedDict
+import errno
+import getopt
+import os
+import sys
+import string
+
+builtin_types = {
+    'str':      'QTYPE_QSTRING',
+    'int':      'QTYPE_QINT',
+    'number':   'QTYPE_QFLOAT',
+    'bool':     'QTYPE_QBOOL',
+    'int8':     'QTYPE_QINT',
+    'int16':    'QTYPE_QINT',
+    'int32':    'QTYPE_QINT',
+    'int64':    'QTYPE_QINT',
+    'uint8':    'QTYPE_QINT',
+    'uint16':   'QTYPE_QINT',
+    'uint32':   'QTYPE_QINT',
+    'uint64':   'QTYPE_QINT',
+    'size':     'QTYPE_QINT',
+}
+
+# Whitelist of commands allowed to return a non-dictionary
+returns_whitelist = [
+    # From QMP:
+    'human-monitor-command',
+    'query-migrate-cache-size',
+    'query-tpm-models',
+    'query-tpm-types',
+    'ringbuf-read',
+
+    # From QGA:
+    'guest-file-open',
+    'guest-fsfreeze-freeze',
+    'guest-fsfreeze-freeze-list',
+    'guest-fsfreeze-status',
+    'guest-fsfreeze-thaw',
+    'guest-get-time',
+    'guest-set-vcpus',
+    'guest-sync',
+    'guest-sync-delimited',
+
+    # From qapi-schema-test:
+    'user_def_cmd3',
+]
+
+enum_types = []
+struct_types = []
+union_types = []
+events = []
+all_names = {}
+
+#
+# Parsing the schema into expressions
+#
+
+def error_path(parent):
+    res = ""
+    while parent:
+        res = ("In file included from %s:%d:\n" % (parent['file'],
+                                                   parent['line'])) + res
+        parent = parent['parent']
+    return res
+
+class QAPISchemaError(Exception):
+    def __init__(self, schema, msg):
+        self.fname = schema.fname
+        self.msg = msg
+        self.col = 1
+        self.line = schema.line
+        for ch in schema.src[schema.line_pos:schema.pos]:
+            if ch == '\t':
+                self.col = (self.col + 7) % 8 + 1
+            else:
+                self.col += 1
+        self.info = schema.incl_info
+
+    def __str__(self):
+        return error_path(self.info) + \
+            "%s:%d:%d: %s" % (self.fname, self.line, self.col, self.msg)
+
+class QAPIExprError(Exception):
+    def __init__(self, expr_info, msg):
+        self.info = expr_info
+        self.msg = msg
+
+    def __str__(self):
+        return error_path(self.info['parent']) + \
+            "%s:%d: %s" % (self.info['file'], self.info['line'], self.msg)
+
+class QAPISchema:
+
+    def __init__(self, fp, previously_included = [], incl_info = None):
+        abs_fname = os.path.abspath(fp.name)
+        fname = fp.name
+        self.fname = fname
+        previously_included.append(abs_fname)
+        self.incl_info = incl_info
+        self.src = fp.read()
+        if self.src == '' or self.src[-1] != '\n':
+            self.src += '\n'
+        self.cursor = 0
+        self.line = 1
+        self.line_pos = 0
+        self.exprs = []
+        self.accept()
+
+        while self.tok != None:
+            expr_info = {'file': fname, 'line': self.line,
+                         'parent': self.incl_info}
+            expr = self.get_expr(False)
+            if isinstance(expr, dict) and "include" in expr:
+                if len(expr) != 1:
+                    raise QAPIExprError(expr_info, "Invalid 'include' directive")
+                include = expr["include"]
+                if not isinstance(include, str):
+                    raise QAPIExprError(expr_info,
+                                        'Expected a file name (string), got: %s'
+                                        % include)
+                incl_abs_fname = os.path.join(os.path.dirname(abs_fname),
+                                              include)
+                # catch inclusion cycle
+                inf = expr_info
+                while inf:
+                    if incl_abs_fname == os.path.abspath(inf['file']):
+                        raise QAPIExprError(expr_info, "Inclusion loop for %s"
+                                            % include)
+                    inf = inf['parent']
+                # skip multiple include of the same file
+                if incl_abs_fname in previously_included:
+                    continue
+                try:
+                    fobj = open(incl_abs_fname, 'r')
+                except IOError, e:
+                    raise QAPIExprError(expr_info,
+                                        '%s: %s' % (e.strerror, include))
+                exprs_include = QAPISchema(fobj, previously_included,
+                                           expr_info)
+                self.exprs.extend(exprs_include.exprs)
+            else:
+                expr_elem = {'expr': expr,
+                             'info': expr_info}
+                self.exprs.append(expr_elem)
+
+    def accept(self):
+        while True:
+            self.tok = self.src[self.cursor]
+            self.pos = self.cursor
+            self.cursor += 1
+            self.val = None
+
+            if self.tok == '#':
+                self.cursor = self.src.find('\n', self.cursor)
+            elif self.tok in ['{', '}', ':', ',', '[', ']']:
+                return
+            elif self.tok == "'":
+                string = ''
+                esc = False
+                while True:
+                    ch = self.src[self.cursor]
+                    self.cursor += 1
+                    if ch == '\n':
+                        raise QAPISchemaError(self,
+                                              'Missing terminating "\'"')
+                    if esc:
+                        if ch == 'b':
+                            string += '\b'
+                        elif ch == 'f':
+                            string += '\f'
+                        elif ch == 'n':
+                            string += '\n'
+                        elif ch == 'r':
+                            string += '\r'
+                        elif ch == 't':
+                            string += '\t'
+                        elif ch == 'u':
+                            value = 0
+                            for x in range(0, 4):
+                                ch = self.src[self.cursor]
+                                self.cursor += 1
+                                if ch not in "0123456789abcdefABCDEF":
+                                    raise QAPISchemaError(self,
+                                                          '\\u escape needs 4 '
+                                                          'hex digits')
+                                value = (value << 4) + int(ch, 16)
+                            # If Python 2 and 3 didn't disagree so much on
+                            # how to handle Unicode, then we could allow
+                            # Unicode string defaults.  But most of QAPI is
+                            # ASCII-only, so we aren't losing much for now.
+                            if not value or value > 0x7f:
+                                raise QAPISchemaError(self,
+                                                      'For now, \\u escape '
+                                                      'only supports non-zero '
+                                                      'values up to \\u007f')
+                            string += chr(value)
+                        elif ch in "\\/'\"":
+                            string += ch
+                        else:
+                            raise QAPISchemaError(self,
+                                                  "Unknown escape \\%s" %ch)
+                        esc = False
+                    elif ch == "\\":
+                        esc = True
+                    elif ch == "'":
+                        self.val = string
+                        return
+                    else:
+                        string += ch
+            elif self.src.startswith("true", self.pos):
+                self.val = True
+                self.cursor += 3
+                return
+            elif self.src.startswith("false", self.pos):
+                self.val = False
+                self.cursor += 4
+                return
+            elif self.src.startswith("null", self.pos):
+                self.val = None
+                self.cursor += 3
+                return
+            elif self.tok == '\n':
+                if self.cursor == len(self.src):
+                    self.tok = None
+                    return
+                self.line += 1
+                self.line_pos = self.cursor
+            elif not self.tok.isspace():
+                raise QAPISchemaError(self, 'Stray "%s"' % self.tok)
+
+    def get_members(self):
+        expr = OrderedDict()
+        if self.tok == '}':
+            self.accept()
+            return expr
+        if self.tok != "'":
+            raise QAPISchemaError(self, 'Expected string or "}"')
+        while True:
+            key = self.val
+            self.accept()
+            if self.tok != ':':
+                raise QAPISchemaError(self, 'Expected ":"')
+            self.accept()
+            if key in expr:
+                raise QAPISchemaError(self, 'Duplicate key "%s"' % key)
+            expr[key] = self.get_expr(True)
+            if self.tok == '}':
+                self.accept()
+                return expr
+            if self.tok != ',':
+                raise QAPISchemaError(self, 'Expected "," or "}"')
+            self.accept()
+            if self.tok != "'":
+                raise QAPISchemaError(self, 'Expected string')
+
+    def get_values(self):
+        expr = []
+        if self.tok == ']':
+            self.accept()
+            return expr
+        if not self.tok in "{['tfn":
+            raise QAPISchemaError(self, 'Expected "{", "[", "]", string, '
+                                  'boolean or "null"')
+        while True:
+            expr.append(self.get_expr(True))
+            if self.tok == ']':
+                self.accept()
+                return expr
+            if self.tok != ',':
+                raise QAPISchemaError(self, 'Expected "," or "]"')
+            self.accept()
+
+    def get_expr(self, nested):
+        if self.tok != '{' and not nested:
+            raise QAPISchemaError(self, 'Expected "{"')
+        if self.tok == '{':
+            self.accept()
+            expr = self.get_members()
+        elif self.tok == '[':
+            self.accept()
+            expr = self.get_values()
+        elif self.tok in "'tfn":
+            expr = self.val
+            self.accept()
+        else:
+            raise QAPISchemaError(self, 'Expected "{", "[" or string')
+        return expr
+
+#
+# Semantic analysis of schema expressions
+#
+
+def find_base_fields(base):
+    base_struct_define = find_struct(base)
+    if not base_struct_define:
+        return None
+    return base_struct_define['data']
+
+# Return the qtype of an alternate branch, or None on error.
+def find_alternate_member_qtype(qapi_type):
+    if builtin_types.has_key(qapi_type):
+        return builtin_types[qapi_type]
+    elif find_struct(qapi_type):
+        return "QTYPE_QDICT"
+    elif find_enum(qapi_type):
+        return "QTYPE_QSTRING"
+    elif find_union(qapi_type):
+        return "QTYPE_QDICT"
+    return None
+
+# Return the discriminator enum define if discriminator is specified as an
+# enum type, otherwise return None.
+def discriminator_find_enum_define(expr):
+    base = expr.get('base')
+    discriminator = expr.get('discriminator')
+
+    if not (discriminator and base):
+        return None
+
+    base_fields = find_base_fields(base)
+    if not base_fields:
+        return None
+
+    discriminator_type = base_fields.get(discriminator)
+    if not discriminator_type:
+        return None
+
+    return find_enum(discriminator_type)
+
+valid_name = re.compile('^[a-zA-Z_][a-zA-Z0-9_.-]*$')
+def check_name(expr_info, source, name, allow_optional = False,
+               enum_member = False):
+    global valid_name
+    membername = name
+
+    if not isinstance(name, str):
+        raise QAPIExprError(expr_info,
+                            "%s requires a string name" % source)
+    if name.startswith('*'):
+        membername = name[1:]
+        if not allow_optional:
+            raise QAPIExprError(expr_info,
+                                "%s does not allow optional name '%s'"
+                                % (source, name))
+    # Enum members can start with a digit, because the generated C
+    # code always prefixes it with the enum name
+    if enum_member:
+        membername = '_' + membername
+    if not valid_name.match(membername):
+        raise QAPIExprError(expr_info,
+                            "%s uses invalid name '%s'" % (source, name))
+
+def add_name(name, info, meta, implicit = False):
+    global all_names
+    check_name(info, "'%s'" % meta, name)
+    if name in all_names:
+        raise QAPIExprError(info,
+                            "%s '%s' is already defined"
+                            % (all_names[name], name))
+    if not implicit and name[-4:] == 'Kind':
+        raise QAPIExprError(info,
+                            "%s '%s' should not end in 'Kind'"
+                            % (meta, name))
+    all_names[name] = meta
+
+def add_struct(definition, info):
+    global struct_types
+    name = definition['struct']
+    add_name(name, info, 'struct')
+    struct_types.append(definition)
+
+def find_struct(name):
+    global struct_types
+    for struct in struct_types:
+        if struct['struct'] == name:
+            return struct
+    return None
+
+def add_union(definition, info):
+    global union_types
+    name = definition['union']
+    add_name(name, info, 'union')
+    union_types.append(definition)
+
+def find_union(name):
+    global union_types
+    for union in union_types:
+        if union['union'] == name:
+            return union
+    return None
+
+def add_enum(name, info, enum_values = None, implicit = False):
+    global enum_types
+    add_name(name, info, 'enum', implicit)
+    enum_types.append({"enum_name": name, "enum_values": enum_values})
+
+def find_enum(name):
+    global enum_types
+    for enum in enum_types:
+        if enum['enum_name'] == name:
+            return enum
+    return None
+
+def is_enum(name):
+    return find_enum(name) != None
+
+def check_type(expr_info, source, value, allow_array = False,
+               allow_dict = False, allow_optional = False,
+               allow_star = False, allow_metas = []):
+    global all_names
+    orig_value = value
+
+    if value is None:
+        return
+
+    if allow_star and value == '**':
+        return
+
+    # Check if array type for value is okay
+    if isinstance(value, list):
+        if not allow_array:
+            raise QAPIExprError(expr_info,
+                                "%s cannot be an array" % source)
+        if len(value) != 1 or not isinstance(value[0], str):
+            raise QAPIExprError(expr_info,
+                                "%s: array type must contain single type name"
+                                % source)
+        value = value[0]
+        orig_value = "array of %s" %value
+
+    # Check if type name for value is okay
+    if isinstance(value, str):
+        if value == '**':
+            raise QAPIExprError(expr_info,
+                                "%s uses '**' but did not request 'gen':false"
+                                % source)
+        if not value in all_names:
+            raise QAPIExprError(expr_info,
+                                "%s uses unknown type '%s'"
+                                % (source, orig_value))
+        if not all_names[value] in allow_metas:
+            raise QAPIExprError(expr_info,
+                                "%s cannot use %s type '%s'"
+                                % (source, all_names[value], orig_value))
+        return
+
+    # value is a dictionary, check that each member is okay
+    if not isinstance(value, OrderedDict):
+        raise QAPIExprError(expr_info,
+                            "%s should be a dictionary" % source)
+    if not allow_dict:
+        raise QAPIExprError(expr_info,
+                            "%s should be a type name" % source)
+    for (key, arg) in value.items():
+        check_name(expr_info, "Member of %s" % source, key,
+                   allow_optional=allow_optional)
+        # Todo: allow dictionaries to represent default values of
+        # an optional argument.
+        check_type(expr_info, "Member '%s' of %s" % (key, source), arg,
+                   allow_array=True, allow_star=allow_star,
+                   allow_metas=['built-in', 'union', 'alternate', 'struct',
+                                'enum'])
+
+def check_member_clash(expr_info, base_name, data, source = ""):
+    base = find_struct(base_name)
+    assert base
+    base_members = base['data']
+    for key in data.keys():
+        if key.startswith('*'):
+            key = key[1:]
+        if key in base_members or "*" + key in base_members:
+            raise QAPIExprError(expr_info,
+                                "Member name '%s'%s clashes with base '%s'"
+                                % (key, source, base_name))
+    if base.get('base'):
+        check_member_clash(expr_info, base['base'], data, source)
+
+def check_command(expr, expr_info):
+    name = expr['command']
+    allow_star = expr.has_key('gen')
+
+    check_type(expr_info, "'data' for command '%s'" % name,
+               expr.get('data'), allow_dict=True, allow_optional=True,
+               allow_metas=['union', 'struct'], allow_star=allow_star)
+    returns_meta = ['union', 'struct']
+    if name in returns_whitelist:
+        returns_meta += ['built-in', 'alternate', 'enum']
+    check_type(expr_info, "'returns' for command '%s'" % name,
+               expr.get('returns'), allow_array=True, allow_dict=True,
+               allow_optional=True, allow_metas=returns_meta,
+               allow_star=allow_star)
+
+def check_event(expr, expr_info):
+    global events
+    name = expr['event']
+    params = expr.get('data')
+
+    if name.upper() == 'MAX':
+        raise QAPIExprError(expr_info, "Event name 'MAX' cannot be created")
+    events.append(name)
+    check_type(expr_info, "'data' for event '%s'" % name,
+               expr.get('data'), allow_dict=True, allow_optional=True,
+               allow_metas=['union', 'struct'])
+
+def check_union(expr, expr_info):
+    name = expr['union']
+    base = expr.get('base')
+    discriminator = expr.get('discriminator')
+    members = expr['data']
+    values = { 'MAX': '(automatic)' }
+
+    # If the object has a member 'base', its value must name a struct,
+    # and there must be a discriminator.
+    if base is not None:
+        if discriminator is None:
+            raise QAPIExprError(expr_info,
+                                "Union '%s' requires a discriminator to go "
+                                "along with base" %name)
+
+    # Two types of unions, determined by discriminator.
+
+    # With no discriminator it is a simple union.
+    if discriminator is None:
+        enum_define = None
+        allow_metas=['built-in', 'union', 'alternate', 'struct', 'enum']
+        if base is not None:
+            raise QAPIExprError(expr_info,
+                                "Simple union '%s' must not have a base"
+                                % name)
+
+    # Else, it's a flat union.
+    else:
+        # The object must have a string member 'base'.
+        if not isinstance(base, str):
+            raise QAPIExprError(expr_info,
+                                "Flat union '%s' must have a string base field"
+                                % name)
+        base_fields = find_base_fields(base)
+        if not base_fields:
+            raise QAPIExprError(expr_info,
+                                "Base '%s' is not a valid struct"
+                                % base)
+
+        # The value of member 'discriminator' must name a non-optional
+        # member of the base struct.
+        check_name(expr_info, "Discriminator of flat union '%s'" % name,
+                   discriminator)
+        discriminator_type = base_fields.get(discriminator)
+        if not discriminator_type:
+            raise QAPIExprError(expr_info,
+                                "Discriminator '%s' is not a member of base "
+                                "struct '%s'"
+                                % (discriminator, base))
+        enum_define = find_enum(discriminator_type)
+        allow_metas=['struct']
+        # Do not allow string discriminator
+        if not enum_define:
+            raise QAPIExprError(expr_info,
+                                "Discriminator '%s' must be of enumeration "
+                                "type" % discriminator)
+
+    # Check every branch
+    for (key, value) in members.items():
+        check_name(expr_info, "Member of union '%s'" % name, key)
+
+        # Each value must name a known type; furthermore, in flat unions,
+        # branches must be a struct with no overlapping member names
+        check_type(expr_info, "Member '%s' of union '%s'" % (key, name),
+                   value, allow_array=not base, allow_metas=allow_metas)
+        if base:
+            branch_struct = find_struct(value)
+            assert branch_struct
+            check_member_clash(expr_info, base, branch_struct['data'],
+                               " of branch '%s'" % key)
+
+        # If the discriminator names an enum type, then all members
+        # of 'data' must also be members of the enum type.
+        if enum_define:
+            if not key in enum_define['enum_values']:
+                raise QAPIExprError(expr_info,
+                                    "Discriminator value '%s' is not found in "
+                                    "enum '%s'" %
+                                    (key, enum_define["enum_name"]))
+
+        # Otherwise, check for conflicts in the generated enum
+        else:
+            c_key = camel_to_upper(key)
+            if c_key in values:
+                raise QAPIExprError(expr_info,
+                                    "Union '%s' member '%s' clashes with '%s'"
+                                    % (name, key, values[c_key]))
+            values[c_key] = key
+
+def check_alternate(expr, expr_info):
+    name = expr['alternate']
+    members = expr['data']
+    values = { 'MAX': '(automatic)' }
+    types_seen = {}
+
+    # Check every branch
+    for (key, value) in members.items():
+        check_name(expr_info, "Member of alternate '%s'" % name, key)
+
+        # Check for conflicts in the generated enum
+        c_key = camel_to_upper(key)
+        if c_key in values:
+            raise QAPIExprError(expr_info,
+                                "Alternate '%s' member '%s' clashes with '%s'"
+                                % (name, key, values[c_key]))
+        values[c_key] = key
+
+        # Ensure alternates have no type conflicts.
+        check_type(expr_info, "Member '%s' of alternate '%s'" % (key, name),
+                   value,
+                   allow_metas=['built-in', 'union', 'struct', 'enum'])
+        qtype = find_alternate_member_qtype(value)
+        assert qtype
+        if qtype in types_seen:
+            raise QAPIExprError(expr_info,
+                                "Alternate '%s' member '%s' can't "
+                                "be distinguished from member '%s'"
+                                % (name, key, types_seen[qtype]))
+        types_seen[qtype] = key
+
+def check_enum(expr, expr_info):
+    name = expr['enum']
+    members = expr.get('data')
+    values = { 'MAX': '(automatic)' }
+
+    if not isinstance(members, list):
+        raise QAPIExprError(expr_info,
+                            "Enum '%s' requires an array for 'data'" % name)
+    for member in members:
+        check_name(expr_info, "Member of enum '%s'" %name, member,
+                   enum_member=True)
+        key = camel_to_upper(member)
+        if key in values:
+            raise QAPIExprError(expr_info,
+                                "Enum '%s' member '%s' clashes with '%s'"
+                                % (name, member, values[key]))
+        values[key] = member
+
+def check_struct(expr, expr_info):
+    name = expr['struct']
+    members = expr['data']
+
+    check_type(expr_info, "'data' for struct '%s'" % name, members,
+               allow_dict=True, allow_optional=True)
+    check_type(expr_info, "'base' for struct '%s'" % name, expr.get('base'),
+               allow_metas=['struct'])
+    if expr.get('base'):
+        check_member_clash(expr_info, expr['base'], expr['data'])
+
+def check_keys(expr_elem, meta, required, optional=[]):
+    expr = expr_elem['expr']
+    info = expr_elem['info']
+    name = expr[meta]
+    if not isinstance(name, str):
+        raise QAPIExprError(info,
+                            "'%s' key must have a string value" % meta)
+    required = required + [ meta ]
+    for (key, value) in expr.items():
+        if not key in required and not key in optional:
+            raise QAPIExprError(info,
+                                "Unknown key '%s' in %s '%s'"
+                                % (key, meta, name))
+        if (key == 'gen' or key == 'success-response') and value != False:
+            raise QAPIExprError(info,
+                                "'%s' of %s '%s' should only use false value"
+                                % (key, meta, name))
+    for key in required:
+        if not expr.has_key(key):
+            raise QAPIExprError(info,
+                                "Key '%s' is missing from %s '%s'"
+                                % (key, meta, name))
+
+def check_exprs(exprs):
+    global all_names
+
+    # Learn the types and check for valid expression keys
+    for builtin in builtin_types.keys():
+        all_names[builtin] = 'built-in'
+    for expr_elem in exprs:
+        expr = expr_elem['expr']
+        info = expr_elem['info']
+        if expr.has_key('enum'):
+            check_keys(expr_elem, 'enum', ['data'])
+            add_enum(expr['enum'], info, expr['data'])
+        elif expr.has_key('union'):
+            check_keys(expr_elem, 'union', ['data'],
+                       ['base', 'discriminator'])
+            add_union(expr, info)
+        elif expr.has_key('alternate'):
+            check_keys(expr_elem, 'alternate', ['data'])
+            add_name(expr['alternate'], info, 'alternate')
+        elif expr.has_key('struct'):
+            check_keys(expr_elem, 'struct', ['data'], ['base'])
+            add_struct(expr, info)
+        elif expr.has_key('command'):
+            check_keys(expr_elem, 'command', [],
+                       ['data', 'returns', 'gen', 'success-response'])
+            add_name(expr['command'], info, 'command')
+        elif expr.has_key('event'):
+            check_keys(expr_elem, 'event', [], ['data'])
+            add_name(expr['event'], info, 'event')
+        else:
+            raise QAPIExprError(expr_elem['info'],
+                                "Expression is missing metatype")
+
+    # Try again for hidden UnionKind enum
+    for expr_elem in exprs:
+        expr = expr_elem['expr']
+        if expr.has_key('union'):
+            if not discriminator_find_enum_define(expr):
+                add_enum('%sKind' % expr['union'], expr_elem['info'],
+                         implicit=True)
+        elif expr.has_key('alternate'):
+            add_enum('%sKind' % expr['alternate'], expr_elem['info'],
+                     implicit=True)
+
+    # Validate that exprs make sense
+    for expr_elem in exprs:
+        expr = expr_elem['expr']
+        info = expr_elem['info']
+
+        if expr.has_key('enum'):
+            check_enum(expr, info)
+        elif expr.has_key('union'):
+            check_union(expr, info)
+        elif expr.has_key('alternate'):
+            check_alternate(expr, info)
+        elif expr.has_key('struct'):
+            check_struct(expr, info)
+        elif expr.has_key('command'):
+            check_command(expr, info)
+        elif expr.has_key('event'):
+            check_event(expr, info)
+        else:
+            assert False, 'unexpected meta type'
+
+    return map(lambda expr_elem: expr_elem['expr'], exprs)
+
+def parse_schema(fname):
+    try:
+        schema = QAPISchema(open(fname, "r"))
+        return check_exprs(schema.exprs)
+    except (QAPISchemaError, QAPIExprError), e:
+        print >>sys.stderr, e
+        exit(1)
+
+#
+# Code generation helpers
+#
+
+def parse_args(typeinfo):
+    if isinstance(typeinfo, str):
+        struct = find_struct(typeinfo)
+        assert struct != None
+        typeinfo = struct['data']
+
+    for member in typeinfo:
+        argname = member
+        argentry = typeinfo[member]
+        optional = False
+        if member.startswith('*'):
+            argname = member[1:]
+            optional = True
+        # Todo: allow argentry to be OrderedDict, for providing the
+        # value of an optional argument.
+        yield (argname, argentry, optional)
+
+def camel_case(name):
+    new_name = ''
+    first = True
+    for ch in name:
+        if ch in ['_', '-']:
+            first = True
+        elif first:
+            new_name += ch.upper()
+            first = False
+        else:
+            new_name += ch.lower()
+    return new_name
+
+# 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 = ''
+    l = len(c_fun_str)
+    for i in range(l):
+        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] != "_":
+            # Case 1: next string is lower
+            # Case 2: previous string is digit
+            if (i < (l - 1) and c_fun_str[i + 1].islower()) or \
+            c_fun_str[i - 1].isdigit():
+                new_name += '_'
+        new_name += c
+    return new_name.lstrip('_').upper()
+
+def c_enum_const(type_name, const_name):
+    return camel_to_upper(type_name + '_' + const_name)
+
+c_name_trans = string.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'])
+    if protect and (name in c89_words | c99_words | c11_words | gcc_words | cpp_words | polluted_words):
+        return "q_" + name
+    return name.translate(c_name_trans)
+
+# Map type @name to the C typedef name for the list form.
+#
+# ['Name'] -> 'NameList', ['x-Foo'] -> 'x_FooList', ['int'] -> 'intList'
+def c_list_type(name):
+    return type_name(name) + 'List'
+
+# Map type @value to the C typedef form.
+#
+# Used for converting 'type' from a 'member':'type' qapi definition
+# into the alphanumeric portion of the type for a generated C parameter,
+# as well as generated C function names.  See c_type() for the rest of
+# the conversion such as adding '*' on pointer types.
+# 'int' -> 'int', '[x-Foo]' -> 'x_FooList', '__a.b_c' -> '__a_b_c'
+def type_name(value):
+    if type(value) == list:
+        return c_list_type(value[0])
+    if value in builtin_types.keys():
+        return value
+    return c_name(value)
+
+eatspace = '\033EATSPACE.'
+pointer_suffix = ' *' + eatspace
+
+# Map type @name to its C type expression.
+# If @is_param, const-qualify the string type.
+#
+# This function is used for computing the full C type of 'member':'name'.
+# A special suffix is added in c_type() for pointer types, and it's
+# stripped in mcgen(). So please notice this when you check the return
+# value of c_type() outside mcgen().
+def c_type(value, is_param=False):
+    if value == 'str':
+        if is_param:
+            return 'const char' + pointer_suffix
+        return 'char' + pointer_suffix
+
+    elif value == 'int':
+        return 'int64_t'
+    elif (value == 'int8' or value == 'int16' or value == 'int32' or
+          value == 'int64' or value == 'uint8' or value == 'uint16' or
+          value == 'uint32' or value == 'uint64'):
+        return value + '_t'
+    elif value == 'size':
+        return 'uint64_t'
+    elif value == 'bool':
+        return 'bool'
+    elif value == 'number':
+        return 'double'
+    elif type(value) == list:
+        return c_list_type(value[0]) + pointer_suffix
+    elif is_enum(value):
+        return c_name(value)
+    elif value == None:
+        return 'void'
+    elif value in events:
+        return camel_case(value) + 'Event' + pointer_suffix
+    else:
+        # complex type name
+        assert isinstance(value, str) and value != ""
+        return c_name(value) + pointer_suffix
+
+def is_c_ptr(value):
+    return c_type(value).endswith(pointer_suffix)
+
+def genindent(count):
+    ret = ""
+    for i 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
+
+def cgen(code, **kwds):
+    indent = genindent(indent_level)
+    lines = code.split('\n')
+    lines = map(lambda x: indent + x, lines)
+    return '\n'.join(lines) % kwds + '\n'
+
+def mcgen(code, **kwds):
+    raw = cgen('\n'.join(code.split('\n')[1:-1]), **kwds)
+    return re.sub(re.escape(eatspace) + ' *', '', raw)
+
+def basename(filename):
+    return filename.split("/")[-1]
+
+def guardname(filename):
+    guard = basename(filename).rsplit(".", 1)[0]
+    for substr in [".", " ", "-"]:
+        guard = guard.replace(substr, "_")
+    return guard.upper() + '_H'
+
+def guardstart(name):
+    return mcgen('''
+
+#ifndef %(name)s
+#define %(name)s
+
+''',
+                 name=guardname(name))
+
+def guardend(name):
+    return mcgen('''
+
+#endif /* %(name)s */
+
+''',
+                 name=guardname(name))
+
+#
+# Common command line parsing
+#
+
+def parse_command_line(extra_options = "", extra_long_options = []):
+
+    try:
+        opts, args = getopt.gnu_getopt(sys.argv[1:],
+                                       "chp:o:" + extra_options,
+                                       ["source", "header", "prefix=",
+                                        "output-dir="] + extra_long_options)
+    except getopt.GetoptError, err:
+        print >>sys.stderr, "%s: %s" % (sys.argv[0], str(err))
+        sys.exit(1)
+
+    output_dir = ""
+    prefix = ""
+    do_c = False
+    do_h = False
+    extra_opts = []
+
+    for oa in opts:
+        o, a = oa
+        if o in ("-p", "--prefix"):
+            prefix = a
+        elif o in ("-o", "--output-dir"):
+            output_dir = a + "/"
+        elif o in ("-c", "--source"):
+            do_c = True
+        elif o in ("-h", "--header"):
+            do_h = True
+        else:
+            extra_opts.append(oa)
+
+    if not do_c and not do_h:
+        do_c = True
+        do_h = True
+
+    if len(args) != 1:
+        print >>sys.stderr, "%s: need exactly one argument" % sys.argv[0]
+        sys.exit(1)
+    fname = args[0]
+
+    return (fname, output_dir, do_c, do_h, prefix, extra_opts)
+
+#
+# Generate output files with boilerplate
+#
+
+def open_output(output_dir, do_c, do_h, prefix, c_file, h_file,
+                c_comment, h_comment):
+    c_file = output_dir + prefix + c_file
+    h_file = output_dir + prefix + h_file
+
+    try:
+        os.makedirs(output_dir)
+    except os.error, e:
+        if e.errno != errno.EEXIST:
+            raise
+
+    def maybe_open(really, name, opt):
+        if really:
+            return open(name, opt)
+        else:
+            import StringIO
+            return StringIO.StringIO()
+
+    fdef = maybe_open(do_c, c_file, 'w')
+    fdecl = maybe_open(do_h, h_file, 'w')
+
+    fdef.write(mcgen('''
+/* AUTOMATICALLY GENERATED, DO NOT MODIFY */
+%(comment)s
+''',
+                     comment = c_comment))
+
+    fdecl.write(mcgen('''
+/* AUTOMATICALLY GENERATED, DO NOT MODIFY */
+%(comment)s
+#ifndef %(guard)s
+#define %(guard)s
+
+''',
+                      comment = h_comment, guard = guardname(h_file)))
+
+    return (fdef, fdecl)
+
+def close_output(fdef, fdecl):
+    fdecl.write('''
+#endif
+''')
+    fdecl.close()
+    fdef.close()