#! /usr/bin/python3 # # Copyright (c) 2005-2007 Niels Provos # Copyright (c) 2007-2012 Niels Provos and Nick Mathewson # All rights reserved. # # Generates marshaling code based on libevent. # pylint: disable=too-many-lines # pylint: disable=too-many-branches # pylint: disable=too-many-public-methods # pylint: disable=too-many-statements # pylint: disable=global-statement # TODO: # 1) propagate the arguments/options parsed by argparse down to the # instantiated factory objects. # 2) move the globals into a class that manages execution, including the # progress outputs that go to stderr at the moment. # 3) emit other languages. import argparse import re import sys _NAME = "event_rpcgen.py" _VERSION = "0.1" # Globals LINE_COUNT = 0 CPPCOMMENT_RE = re.compile(r"\/\/.*$") NONIDENT_RE = re.compile(r"\W") PREPROCESSOR_DEF_RE = re.compile(r"^#define") STRUCT_REF_RE = re.compile(r"^struct\[(?P[a-zA-Z_][a-zA-Z0-9_]*)\]$") STRUCT_DEF_RE = re.compile(r"^struct +[a-zA-Z_][a-zA-Z0-9_]* *{$") WHITESPACE_RE = re.compile(r"\s+") HEADER_DIRECT = [] CPP_DIRECT = [] QUIETLY = False def declare(s): if not QUIETLY: print(s) def TranslateList(mylist, mydict): return [x % mydict for x in mylist] class RpcGenError(Exception): """An Exception class for parse errors.""" def __init__(self, why): # pylint: disable=super-init-not-called self.why = why def __str__(self): return str(self.why) # Holds everything that makes a struct class Struct(object): def __init__(self, name): self._name = name self._entries = [] self._tags = {} declare(" Created struct: %s" % name) def AddEntry(self, entry): if entry.Tag() in self._tags: raise RpcGenError( 'Entry "%s" duplicates tag number %d from "%s" ' "around line %d" % (entry.Name(), entry.Tag(), self._tags[entry.Tag()], LINE_COUNT) ) self._entries.append(entry) self._tags[entry.Tag()] = entry.Name() declare(" Added entry: %s" % entry.Name()) def Name(self): return self._name def EntryTagName(self, entry): """Creates the name inside an enumeration for distinguishing data types.""" name = "%s_%s" % (self._name, entry.Name()) return name.upper() @staticmethod def PrintIndented(filep, ident, code): """Takes an array, add indentation to each entry and prints it.""" for entry in code: filep.write("%s%s\n" % (ident, entry)) class StructCCode(Struct): """ Knows how to generate C code for a struct """ def __init__(self, name): Struct.__init__(self, name) def PrintTags(self, filep): """Prints the tag definitions for a structure.""" filep.write("/* Tag definition for %s */\n" % self._name) filep.write("enum %s_ {\n" % self._name.lower()) for entry in self._entries: filep.write(" %s=%d,\n" % (self.EntryTagName(entry), entry.Tag())) filep.write(" %s_MAX_TAGS\n" % (self._name.upper())) filep.write("};\n\n") def PrintForwardDeclaration(self, filep): filep.write("struct %s;\n" % self._name) def PrintDeclaration(self, filep): filep.write("/* Structure declaration for %s */\n" % self._name) filep.write("struct %s_access_ {\n" % self._name) for entry in self._entries: dcl = entry.AssignDeclaration("(*%s_assign)" % entry.Name()) dcl.extend(entry.GetDeclaration("(*%s_get)" % entry.Name())) if entry.Array(): dcl.extend(entry.AddDeclaration("(*%s_add)" % entry.Name())) self.PrintIndented(filep, " ", dcl) filep.write("};\n\n") filep.write("struct %s {\n" % self._name) filep.write(" struct %s_access_ *base;\n\n" % self._name) for entry in self._entries: dcl = entry.Declaration() self.PrintIndented(filep, " ", dcl) filep.write("\n") for entry in self._entries: filep.write(" ev_uint8_t %s_set;\n" % entry.Name()) filep.write("};\n\n") filep.write( """struct %(name)s *%(name)s_new(void); struct %(name)s *%(name)s_new_with_arg(void *); void %(name)s_free(struct %(name)s *); void %(name)s_clear(struct %(name)s *); void %(name)s_marshal(struct evbuffer *, const struct %(name)s *); int %(name)s_unmarshal(struct %(name)s *, struct evbuffer *); int %(name)s_complete(struct %(name)s *); void evtag_marshal_%(name)s(struct evbuffer *, ev_uint32_t, const struct %(name)s *); int evtag_unmarshal_%(name)s(struct evbuffer *, ev_uint32_t, struct %(name)s *);\n""" % {"name": self._name} ) # Write a setting function of every variable for entry in self._entries: self.PrintIndented( filep, "", entry.AssignDeclaration(entry.AssignFuncName()) ) self.PrintIndented(filep, "", entry.GetDeclaration(entry.GetFuncName())) if entry.Array(): self.PrintIndented(filep, "", entry.AddDeclaration(entry.AddFuncName())) filep.write("/* --- %s done --- */\n\n" % self._name) def PrintCode(self, filep): filep.write( """/* * Implementation of %s */ """ % (self._name) ) filep.write( """ static struct %(name)s_access_ %(name)s_base__ = { """ % {"name": self._name} ) for entry in self._entries: self.PrintIndented(filep, " ", entry.CodeBase()) filep.write("};\n\n") # Creation filep.write( """struct %(name)s * %(name)s_new(void) { return %(name)s_new_with_arg(NULL); } struct %(name)s * %(name)s_new_with_arg(void *unused) { struct %(name)s *tmp; if ((tmp = malloc(sizeof(struct %(name)s))) == NULL) { event_warn("%%s: malloc", __func__); return (NULL); } tmp->base = &%(name)s_base__; """ % {"name": self._name} ) for entry in self._entries: self.PrintIndented(filep, " ", entry.CodeInitialize("tmp")) filep.write(" tmp->%s_set = 0;\n\n" % entry.Name()) filep.write( """ return (tmp); } """ ) # Adding for entry in self._entries: if entry.Array(): self.PrintIndented(filep, "", entry.CodeAdd()) filep.write("\n") # Assigning for entry in self._entries: self.PrintIndented(filep, "", entry.CodeAssign()) filep.write("\n") # Getting for entry in self._entries: self.PrintIndented(filep, "", entry.CodeGet()) filep.write("\n") # Clearing filep.write( """void %(name)s_clear(struct %(name)s *tmp) { """ % {"name": self._name} ) for entry in self._entries: self.PrintIndented(filep, " ", entry.CodeClear("tmp")) filep.write("}\n\n") # Freeing filep.write( """void %(name)s_free(struct %(name)s *tmp) { """ % {"name": self._name} ) for entry in self._entries: self.PrintIndented(filep, " ", entry.CodeFree("tmp")) filep.write( """ free(tmp); } """ ) # Marshaling filep.write( """void %(name)s_marshal(struct evbuffer *evbuf, const struct %(name)s *tmp) { """ % {"name": self._name} ) for entry in self._entries: indent = " " # Optional entries do not have to be set if entry.Optional(): indent += " " filep.write(" if (tmp->%s_set) {\n" % entry.Name()) self.PrintIndented( filep, indent, entry.CodeMarshal( "evbuf", self.EntryTagName(entry), entry.GetVarName("tmp"), entry.GetVarLen("tmp"), ), ) if entry.Optional(): filep.write(" }\n") filep.write("}\n\n") # Unmarshaling filep.write( """int %(name)s_unmarshal(struct %(name)s *tmp, struct evbuffer *evbuf) { ev_uint32_t tag; while (evbuffer_get_length(evbuf) > 0) { if (evtag_peek(evbuf, &tag) == -1) return (-1); switch (tag) { """ % {"name": self._name} ) for entry in self._entries: filep.write(" case %s:\n" % (self.EntryTagName(entry))) if not entry.Array(): filep.write( """ if (tmp->%s_set) return (-1); """ % (entry.Name()) ) self.PrintIndented( filep, " ", entry.CodeUnmarshal( "evbuf", self.EntryTagName(entry), entry.GetVarName("tmp"), entry.GetVarLen("tmp"), ), ) filep.write( """ tmp->%s_set = 1; break; """ % (entry.Name()) ) filep.write( """ default: return -1; } } """ ) # Check if it was decoded completely filep.write( """ if (%(name)s_complete(tmp) == -1) return (-1); return (0); } """ % {"name": self._name} ) # Checking if a structure has all the required data filep.write( """ int %(name)s_complete(struct %(name)s *msg) { """ % {"name": self._name} ) for entry in self._entries: if not entry.Optional(): code = [ """if (!msg->%(name)s_set) return (-1);""" ] code = TranslateList(code, entry.GetTranslation()) self.PrintIndented(filep, " ", code) self.PrintIndented( filep, " ", entry.CodeComplete("msg", entry.GetVarName("msg")) ) filep.write( """ return (0); } """ ) # Complete message unmarshaling filep.write( """ int evtag_unmarshal_%(name)s(struct evbuffer *evbuf, ev_uint32_t need_tag, struct %(name)s *msg) { ev_uint32_t tag; int res = -1; struct evbuffer *tmp = evbuffer_new(); if (evtag_unmarshal(evbuf, &tag, tmp) == -1 || tag != need_tag) goto error; if (%(name)s_unmarshal(msg, tmp) == -1) goto error; res = 0; error: evbuffer_free(tmp); return (res); } """ % {"name": self._name} ) # Complete message marshaling filep.write( """ void evtag_marshal_%(name)s(struct evbuffer *evbuf, ev_uint32_t tag, const struct %(name)s *msg) { struct evbuffer *buf_ = evbuffer_new(); assert(buf_ != NULL); %(name)s_marshal(buf_, msg); evtag_marshal_buffer(evbuf, tag, buf_); evbuffer_free(buf_); } """ % {"name": self._name} ) class Entry(object): def __init__(self, ent_type, name, tag): self._type = ent_type self._name = name self._tag = int(tag) self._ctype = ent_type self._optional = False self._can_be_array = False self._array = False self._line_count = -1 self._struct = None self._refname = None self._optpointer = True self._optaddarg = True @staticmethod def GetInitializer(): raise NotImplementedError("Entry does not provide an initializer") def SetStruct(self, struct): self._struct = struct def LineCount(self): assert self._line_count != -1 return self._line_count def SetLineCount(self, number): self._line_count = number def Array(self): return self._array def Optional(self): return self._optional def Tag(self): return self._tag def Name(self): return self._name def Type(self): return self._type def MakeArray(self): self._array = True def MakeOptional(self): self._optional = True def Verify(self): if self.Array() and not self._can_be_array: raise RpcGenError( 'Entry "%s" cannot be created as an array ' "around line %d" % (self._name, self.LineCount()) ) if not self._struct: raise RpcGenError( 'Entry "%s" does not know which struct it belongs to ' "around line %d" % (self._name, self.LineCount()) ) if self._optional and self._array: raise RpcGenError( 'Entry "%s" has illegal combination of optional and array ' "around line %d" % (self._name, self.LineCount()) ) def GetTranslation(self, extradict=None): if extradict is None: extradict = {} mapping = { "parent_name": self._struct.Name(), "name": self._name, "ctype": self._ctype, "refname": self._refname, "optpointer": self._optpointer and "*" or "", "optreference": self._optpointer and "&" or "", "optaddarg": self._optaddarg and ", const %s value" % self._ctype or "", } for (k, v) in list(extradict.items()): mapping[k] = v return mapping def GetVarName(self, var): return "%(var)s->%(name)s_data" % self.GetTranslation({"var": var}) def GetVarLen(self, _var): return "sizeof(%s)" % self._ctype def GetFuncName(self): return "%s_%s_get" % (self._struct.Name(), self._name) def GetDeclaration(self, funcname): code = [ "int %s(struct %s *, %s *);" % (funcname, self._struct.Name(), self._ctype) ] return code def CodeGet(self): code = """int %(parent_name)s_%(name)s_get(struct %(parent_name)s *msg, %(ctype)s *value) { if (msg->%(name)s_set != 1) return (-1); *value = msg->%(name)s_data; return (0); }""" code = code % self.GetTranslation() return code.split("\n") def AssignFuncName(self): return "%s_%s_assign" % (self._struct.Name(), self._name) def AddFuncName(self): return "%s_%s_add" % (self._struct.Name(), self._name) def AssignDeclaration(self, funcname): code = [ "int %s(struct %s *, const %s);" % (funcname, self._struct.Name(), self._ctype) ] return code def CodeAssign(self): code = [ "int", "%(parent_name)s_%(name)s_assign(struct %(parent_name)s *msg," " const %(ctype)s value)", "{", " msg->%(name)s_set = 1;", " msg->%(name)s_data = value;", " return (0);", "}", ] code = "\n".join(code) code = code % self.GetTranslation() return code.split("\n") def CodeClear(self, structname): code = ["%s->%s_set = 0;" % (structname, self.Name())] return code @staticmethod def CodeComplete(_structname, _var_name): return [] @staticmethod def CodeFree(_name): return [] def CodeBase(self): code = ["%(parent_name)s_%(name)s_assign,", "%(parent_name)s_%(name)s_get,"] if self.Array(): code.append("%(parent_name)s_%(name)s_add,") code = "\n".join(code) code = code % self.GetTranslation() return code.split("\n") class EntryBytes(Entry): def __init__(self, ent_type, name, tag, length): # Init base class super(EntryBytes, self).__init__(ent_type, name, tag) self._length = length self._ctype = "ev_uint8_t" @staticmethod def GetInitializer(): return "NULL" def GetVarLen(self, _var): return "(%s)" % self._length @staticmethod def CodeArrayAdd(varname, _value): # XXX: copy here return ["%(varname)s = NULL;" % {"varname": varname}] def GetDeclaration(self, funcname): code = [ "int %s(struct %s *, %s **);" % (funcname, self._struct.Name(), self._ctype) ] return code def AssignDeclaration(self, funcname): code = [ "int %s(struct %s *, const %s *);" % (funcname, self._struct.Name(), self._ctype) ] return code def Declaration(self): dcl = ["ev_uint8_t %s_data[%s];" % (self._name, self._length)] return dcl def CodeGet(self): name = self._name code = [ "int", "%s_%s_get(struct %s *msg, %s **value)" % (self._struct.Name(), name, self._struct.Name(), self._ctype), "{", " if (msg->%s_set != 1)" % name, " return (-1);", " *value = msg->%s_data;" % name, " return (0);", "}", ] return code def CodeAssign(self): name = self._name code = [ "int", "%s_%s_assign(struct %s *msg, const %s *value)" % (self._struct.Name(), name, self._struct.Name(), self._ctype), "{", " msg->%s_set = 1;" % name, " memcpy(msg->%s_data, value, %s);" % (name, self._length), " return (0);", "}", ] return code def CodeUnmarshal(self, buf, tag_name, var_name, var_len): code = [ "if (evtag_unmarshal_fixed(%(buf)s, %(tag)s, " "%(var)s, %(varlen)s) == -1) {", ' event_warnx("%%s: failed to unmarshal %(name)s", __func__);', " return (-1);", "}", ] return TranslateList( code, self.GetTranslation( {"var": var_name, "varlen": var_len, "buf": buf, "tag": tag_name} ), ) @staticmethod def CodeMarshal(buf, tag_name, var_name, var_len): code = ["evtag_marshal(%s, %s, %s, %s);" % (buf, tag_name, var_name, var_len)] return code def CodeClear(self, structname): code = [ "%s->%s_set = 0;" % (structname, self.Name()), "memset(%s->%s_data, 0, sizeof(%s->%s_data));" % (structname, self._name, structname, self._name), ] return code def CodeInitialize(self, name): code = [ "memset(%s->%s_data, 0, sizeof(%s->%s_data));" % (name, self._name, name, self._name) ] return code def Verify(self): if not self._length: raise RpcGenError( 'Entry "%s" needs a length ' "around line %d" % (self._name, self.LineCount()) ) super(EntryBytes, self).Verify() class EntryInt(Entry): def __init__(self, ent_type, name, tag, bits=32): # Init base class super(EntryInt, self).__init__(ent_type, name, tag) self._can_be_array = True if bits == 32: self._ctype = "ev_uint32_t" self._marshal_type = "int" if bits == 64: self._ctype = "ev_uint64_t" self._marshal_type = "int64" @staticmethod def GetInitializer(): return "0" @staticmethod def CodeArrayFree(_var): return [] @staticmethod def CodeArrayAssign(varname, srcvar): return ["%(varname)s = %(srcvar)s;" % {"varname": varname, "srcvar": srcvar}] @staticmethod def CodeArrayAdd(varname, value): """Returns a new entry of this type.""" return ["%(varname)s = %(value)s;" % {"varname": varname, "value": value}] def CodeUnmarshal(self, buf, tag_name, var_name, _var_len): code = [ "if (evtag_unmarshal_%(ma)s(%(buf)s, %(tag)s, &%(var)s) == -1) {", ' event_warnx("%%s: failed to unmarshal %(name)s", __func__);', " return (-1);", "}", ] code = "\n".join(code) % self.GetTranslation( {"ma": self._marshal_type, "buf": buf, "tag": tag_name, "var": var_name} ) return code.split("\n") def CodeMarshal(self, buf, tag_name, var_name, _var_len): code = [ "evtag_marshal_%s(%s, %s, %s);" % (self._marshal_type, buf, tag_name, var_name) ] return code def Declaration(self): dcl = ["%s %s_data;" % (self._ctype, self._name)] return dcl def CodeInitialize(self, name): code = ["%s->%s_data = 0;" % (name, self._name)] return code class EntryString(Entry): def __init__(self, ent_type, name, tag): # Init base class super(EntryString, self).__init__(ent_type, name, tag) self._can_be_array = True self._ctype = "char *" @staticmethod def GetInitializer(): return "NULL" @staticmethod def CodeArrayFree(varname): code = ["if (%(var)s != NULL) free(%(var)s);"] return TranslateList(code, {"var": varname}) @staticmethod def CodeArrayAssign(varname, srcvar): code = [ "if (%(var)s != NULL)", " free(%(var)s);", "%(var)s = strdup(%(srcvar)s);", "if (%(var)s == NULL) {", ' event_warnx("%%s: strdup", __func__);', " return (-1);", "}", ] return TranslateList(code, {"var": varname, "srcvar": srcvar}) @staticmethod def CodeArrayAdd(varname, value): code = [ "if (%(value)s != NULL) {", " %(var)s = strdup(%(value)s);", " if (%(var)s == NULL) {", " goto error;", " }", "} else {", " %(var)s = NULL;", "}", ] return TranslateList(code, {"var": varname, "value": value}) def GetVarLen(self, var): return "strlen(%s)" % self.GetVarName(var) @staticmethod def CodeMakeInitalize(varname): return "%(varname)s = NULL;" % {"varname": varname} def CodeAssign(self): code = """int %(parent_name)s_%(name)s_assign(struct %(parent_name)s *msg, const %(ctype)s value) { if (msg->%(name)s_data != NULL) free(msg->%(name)s_data); if ((msg->%(name)s_data = strdup(value)) == NULL) return (-1); msg->%(name)s_set = 1; return (0); }""" % ( self.GetTranslation() ) return code.split("\n") def CodeUnmarshal(self, buf, tag_name, var_name, _var_len): code = [ "if (evtag_unmarshal_string(%(buf)s, %(tag)s, &%(var)s) == -1) {", ' event_warnx("%%s: failed to unmarshal %(name)s", __func__);', " return (-1);", "}", ] code = "\n".join(code) % self.GetTranslation( {"buf": buf, "tag": tag_name, "var": var_name} ) return code.split("\n") @staticmethod def CodeMarshal(buf, tag_name, var_name, _var_len): code = ["evtag_marshal_string(%s, %s, %s);" % (buf, tag_name, var_name)] return code def CodeClear(self, structname): code = [ "if (%s->%s_set == 1) {" % (structname, self.Name()), " free(%s->%s_data);" % (structname, self.Name()), " %s->%s_data = NULL;" % (structname, self.Name()), " %s->%s_set = 0;" % (structname, self.Name()), "}", ] return code def CodeInitialize(self, name): code = ["%s->%s_data = NULL;" % (name, self._name)] return code def CodeFree(self, name): code = [ "if (%s->%s_data != NULL)" % (name, self._name), " free (%s->%s_data);" % (name, self._name), ] return code def Declaration(self): dcl = ["char *%s_data;" % self._name] return dcl class EntryStruct(Entry): def __init__(self, ent_type, name, tag, refname): # Init base class super(EntryStruct, self).__init__(ent_type, name, tag) self._optpointer = False self._can_be_array = True self._refname = refname self._ctype = "struct %s*" % refname self._optaddarg = False def GetInitializer(self): return "NULL" def GetVarLen(self, _var): return "-1" def CodeArrayAdd(self, varname, _value): code = [ "%(varname)s = %(refname)s_new();", "if (%(varname)s == NULL)", " goto error;", ] return TranslateList(code, self.GetTranslation({"varname": varname})) def CodeArrayFree(self, var): code = ["%(refname)s_free(%(var)s);" % self.GetTranslation({"var": var})] return code def CodeArrayAssign(self, var, srcvar): code = [ "int had_error = 0;", "struct evbuffer *tmp = NULL;", "%(refname)s_clear(%(var)s);", "if ((tmp = evbuffer_new()) == NULL) {", ' event_warn("%%s: evbuffer_new()", __func__);', " had_error = 1;", " goto done;", "}", "%(refname)s_marshal(tmp, %(srcvar)s);", "if (%(refname)s_unmarshal(%(var)s, tmp) == -1) {", ' event_warnx("%%s: %(refname)s_unmarshal", __func__);', " had_error = 1;", " goto done;", "}", "done:", "if (tmp != NULL)", " evbuffer_free(tmp);", "if (had_error) {", " %(refname)s_clear(%(var)s);", " return (-1);", "}", ] return TranslateList(code, self.GetTranslation({"var": var, "srcvar": srcvar})) def CodeGet(self): name = self._name code = [ "int", "%s_%s_get(struct %s *msg, %s *value)" % (self._struct.Name(), name, self._struct.Name(), self._ctype), "{", " if (msg->%s_set != 1) {" % name, " msg->%s_data = %s_new();" % (name, self._refname), " if (msg->%s_data == NULL)" % name, " return (-1);", " msg->%s_set = 1;" % name, " }", " *value = msg->%s_data;" % name, " return (0);", "}", ] return code def CodeAssign(self): code = ( """int %(parent_name)s_%(name)s_assign(struct %(parent_name)s *msg, const %(ctype)s value) { struct evbuffer *tmp = NULL; if (msg->%(name)s_set) { %(refname)s_clear(msg->%(name)s_data); msg->%(name)s_set = 0; } else { msg->%(name)s_data = %(refname)s_new(); if (msg->%(name)s_data == NULL) { event_warn("%%s: %(refname)s_new()", __func__); goto error; } } if ((tmp = evbuffer_new()) == NULL) { event_warn("%%s: evbuffer_new()", __func__); goto error; } %(refname)s_marshal(tmp, value); if (%(refname)s_unmarshal(msg->%(name)s_data, tmp) == -1) { event_warnx("%%s: %(refname)s_unmarshal", __func__); goto error; } msg->%(name)s_set = 1; evbuffer_free(tmp); return (0); error: if (tmp != NULL) evbuffer_free(tmp); if (msg->%(name)s_data != NULL) { %(refname)s_free(msg->%(name)s_data); msg->%(name)s_data = NULL; } return (-1); }""" % self.GetTranslation() ) return code.split("\n") def CodeComplete(self, structname, var_name): code = [ "if (%(structname)s->%(name)s_set && " "%(refname)s_complete(%(var)s) == -1)", " return (-1);", ] return TranslateList( code, self.GetTranslation({"structname": structname, "var": var_name}) ) def CodeUnmarshal(self, buf, tag_name, var_name, _var_len): code = [ "%(var)s = %(refname)s_new();", "if (%(var)s == NULL)", " return (-1);", "if (evtag_unmarshal_%(refname)s(%(buf)s, %(tag)s, ", " %(var)s) == -1) {", ' event_warnx("%%s: failed to unmarshal %(name)s", __func__);', " return (-1);", "}", ] code = "\n".join(code) % self.GetTranslation( {"buf": buf, "tag": tag_name, "var": var_name} ) return code.split("\n") def CodeMarshal(self, buf, tag_name, var_name, _var_len): code = [ "evtag_marshal_%s(%s, %s, %s);" % (self._refname, buf, tag_name, var_name) ] return code def CodeClear(self, structname): code = [ "if (%s->%s_set == 1) {" % (structname, self.Name()), " %s_free(%s->%s_data);" % (self._refname, structname, self.Name()), " %s->%s_data = NULL;" % (structname, self.Name()), " %s->%s_set = 0;" % (structname, self.Name()), "}", ] return code def CodeInitialize(self, name): code = ["%s->%s_data = NULL;" % (name, self._name)] return code def CodeFree(self, name): code = [ "if (%s->%s_data != NULL)" % (name, self._name), " %s_free(%s->%s_data);" % (self._refname, name, self._name), ] return code def Declaration(self): dcl = ["%s %s_data;" % (self._ctype, self._name)] return dcl class EntryVarBytes(Entry): def __init__(self, ent_type, name, tag): # Init base class super(EntryVarBytes, self).__init__(ent_type, name, tag) self._ctype = "ev_uint8_t *" @staticmethod def GetInitializer(): return "NULL" def GetVarLen(self, var): return "%(var)s->%(name)s_length" % self.GetTranslation({"var": var}) @staticmethod def CodeArrayAdd(varname, _value): # xxx: copy return ["%(varname)s = NULL;" % {"varname": varname}] def GetDeclaration(self, funcname): code = [ "int %s(struct %s *, %s *, ev_uint32_t *);" % (funcname, self._struct.Name(), self._ctype) ] return code def AssignDeclaration(self, funcname): code = [ "int %s(struct %s *, const %s, ev_uint32_t);" % (funcname, self._struct.Name(), self._ctype) ] return code def CodeAssign(self): name = self._name code = [ "int", "%s_%s_assign(struct %s *msg, " "const %s value, ev_uint32_t len)" % (self._struct.Name(), name, self._struct.Name(), self._ctype), "{", " if (msg->%s_data != NULL)" % name, " free (msg->%s_data);" % name, " msg->%s_data = malloc(len);" % name, " if (msg->%s_data == NULL)" % name, " return (-1);", " msg->%s_set = 1;" % name, " msg->%s_length = len;" % name, " memcpy(msg->%s_data, value, len);" % name, " return (0);", "}", ] return code def CodeGet(self): name = self._name code = [ "int", "%s_%s_get(struct %s *msg, %s *value, ev_uint32_t *plen)" % (self._struct.Name(), name, self._struct.Name(), self._ctype), "{", " if (msg->%s_set != 1)" % name, " return (-1);", " *value = msg->%s_data;" % name, " *plen = msg->%s_length;" % name, " return (0);", "}", ] return code def CodeUnmarshal(self, buf, tag_name, var_name, var_len): code = [ "if (evtag_payload_length(%(buf)s, &%(varlen)s) == -1)", " return (-1);", # We do not want DoS opportunities "if (%(varlen)s > evbuffer_get_length(%(buf)s))", " return (-1);", "if ((%(var)s = malloc(%(varlen)s)) == NULL)", " return (-1);", "if (evtag_unmarshal_fixed(%(buf)s, %(tag)s, %(var)s, " "%(varlen)s) == -1) {", ' event_warnx("%%s: failed to unmarshal %(name)s", __func__);', " return (-1);", "}", ] code = "\n".join(code) % self.GetTranslation( {"buf": buf, "tag": tag_name, "var": var_name, "varlen": var_len} ) return code.split("\n") @staticmethod def CodeMarshal(buf, tag_name, var_name, var_len): code = ["evtag_marshal(%s, %s, %s, %s);" % (buf, tag_name, var_name, var_len)] return code def CodeClear(self, structname): code = [ "if (%s->%s_set == 1) {" % (structname, self.Name()), " free (%s->%s_data);" % (structname, self.Name()), " %s->%s_data = NULL;" % (structname, self.Name()), " %s->%s_length = 0;" % (structname, self.Name()), " %s->%s_set = 0;" % (structname, self.Name()), "}", ] return code def CodeInitialize(self, name): code = [ "%s->%s_data = NULL;" % (name, self._name), "%s->%s_length = 0;" % (name, self._name), ] return code def CodeFree(self, name): code = [ "if (%s->%s_data != NULL)" % (name, self._name), " free(%s->%s_data);" % (name, self._name), ] return code def Declaration(self): dcl = [ "ev_uint8_t *%s_data;" % self._name, "ev_uint32_t %s_length;" % self._name, ] return dcl class EntryArray(Entry): _index = None def __init__(self, entry): # Init base class super(EntryArray, self).__init__(entry._type, entry._name, entry._tag) self._entry = entry self._refname = entry._refname self._ctype = self._entry._ctype self._optional = True self._optpointer = self._entry._optpointer self._optaddarg = self._entry._optaddarg # provide a new function for accessing the variable name def GetVarName(var_name): return "%(var)s->%(name)s_data[%(index)s]" % self._entry.GetTranslation( {"var": var_name, "index": self._index} ) self._entry.GetVarName = GetVarName def GetInitializer(self): return "NULL" def GetVarName(self, var): return var def GetVarLen(self, _var_name): return "-1" def GetDeclaration(self, funcname): """Allows direct access to elements of the array.""" code = [ "int %(funcname)s(struct %(parent_name)s *, int, %(ctype)s *);" % self.GetTranslation({"funcname": funcname}) ] return code def AssignDeclaration(self, funcname): code = [ "int %s(struct %s *, int, const %s);" % (funcname, self._struct.Name(), self._ctype) ] return code def AddDeclaration(self, funcname): code = [ "%(ctype)s %(optpointer)s " "%(funcname)s(struct %(parent_name)s *msg%(optaddarg)s);" % self.GetTranslation({"funcname": funcname}) ] return code def CodeGet(self): code = """int %(parent_name)s_%(name)s_get(struct %(parent_name)s *msg, int offset, %(ctype)s *value) { if (!msg->%(name)s_set || offset < 0 || offset >= msg->%(name)s_length) return (-1); *value = msg->%(name)s_data[offset]; return (0); } """ % ( self.GetTranslation() ) return code.splitlines() def CodeAssign(self): code = [ "int", "%(parent_name)s_%(name)s_assign(struct %(parent_name)s *msg, int off,", " const %(ctype)s value)", "{", " if (!msg->%(name)s_set || off < 0 || off >= msg->%(name)s_length)", " return (-1);", "", " {", ] code = TranslateList(code, self.GetTranslation()) codearrayassign = self._entry.CodeArrayAssign( "msg->%(name)s_data[off]" % self.GetTranslation(), "value" ) code += [" " + x for x in codearrayassign] code += TranslateList([" }", " return (0);", "}"], self.GetTranslation()) return code def CodeAdd(self): codearrayadd = self._entry.CodeArrayAdd( "msg->%(name)s_data[msg->%(name)s_length - 1]" % self.GetTranslation(), "value", ) code = [ "static int", "%(parent_name)s_%(name)s_expand_to_hold_more(" "struct %(parent_name)s *msg)", "{", " int tobe_allocated = msg->%(name)s_num_allocated;", " %(ctype)s* new_data = NULL;", " tobe_allocated = !tobe_allocated ? 1 : tobe_allocated << 1;", " new_data = (%(ctype)s*) realloc(msg->%(name)s_data,", " tobe_allocated * sizeof(%(ctype)s));", " if (new_data == NULL)", " return -1;", " msg->%(name)s_data = new_data;", " msg->%(name)s_num_allocated = tobe_allocated;", " return 0;", "}", "", "%(ctype)s %(optpointer)s", "%(parent_name)s_%(name)s_add(struct %(parent_name)s *msg%(optaddarg)s)", "{", " if (++msg->%(name)s_length >= msg->%(name)s_num_allocated) {", " if (%(parent_name)s_%(name)s_expand_to_hold_more(msg)<0)", " goto error;", " }", ] code = TranslateList(code, self.GetTranslation()) code += [" " + x for x in codearrayadd] code += TranslateList( [ " msg->%(name)s_set = 1;", " return %(optreference)s(msg->%(name)s_data[" "msg->%(name)s_length - 1]);", "error:", " --msg->%(name)s_length;", " return (NULL);", "}", ], self.GetTranslation(), ) return code def CodeComplete(self, structname, var_name): self._index = "i" tmp = self._entry.CodeComplete(structname, self._entry.GetVarName(var_name)) # skip the whole loop if there is nothing to check if not tmp: return [] translate = self.GetTranslation({"structname": structname}) code = [ "{", " int i;", " for (i = 0; i < %(structname)s->%(name)s_length; ++i) {", ] code = TranslateList(code, translate) code += [" " + x for x in tmp] code += [" }", "}"] return code def CodeUnmarshal(self, buf, tag_name, var_name, _var_len): translate = self.GetTranslation( { "var": var_name, "buf": buf, "tag": tag_name, "init": self._entry.GetInitializer(), } ) code = [ "if (%(var)s->%(name)s_length >= %(var)s->%(name)s_num_allocated &&", " %(parent_name)s_%(name)s_expand_to_hold_more(%(var)s) < 0) {", ' puts("HEY NOW");', " return (-1);", "}", ] # the unmarshal code directly returns code = TranslateList(code, translate) self._index = "%(var)s->%(name)s_length" % translate code += self._entry.CodeUnmarshal( buf, tag_name, self._entry.GetVarName(var_name), self._entry.GetVarLen(var_name), ) code += ["++%(var)s->%(name)s_length;" % translate] return code def CodeMarshal(self, buf, tag_name, var_name, _var_len): code = ["{", " int i;", " for (i = 0; i < %(var)s->%(name)s_length; ++i) {"] self._index = "i" code += self._entry.CodeMarshal( buf, tag_name, self._entry.GetVarName(var_name), self._entry.GetVarLen(var_name), ) code += [" }", "}"] code = "\n".join(code) % self.GetTranslation({"var": var_name}) return code.split("\n") def CodeClear(self, structname): translate = self.GetTranslation({"structname": structname}) codearrayfree = self._entry.CodeArrayFree( "%(structname)s->%(name)s_data[i]" % self.GetTranslation({"structname": structname}) ) code = ["if (%(structname)s->%(name)s_set == 1) {"] if codearrayfree: code += [ " int i;", " for (i = 0; i < %(structname)s->%(name)s_length; ++i) {", ] code = TranslateList(code, translate) if codearrayfree: code += [" " + x for x in codearrayfree] code += [" }"] code += TranslateList( [ " free(%(structname)s->%(name)s_data);", " %(structname)s->%(name)s_data = NULL;", " %(structname)s->%(name)s_set = 0;", " %(structname)s->%(name)s_length = 0;", " %(structname)s->%(name)s_num_allocated = 0;", "}", ], translate, ) return code def CodeInitialize(self, name): code = [ "%s->%s_data = NULL;" % (name, self._name), "%s->%s_length = 0;" % (name, self._name), "%s->%s_num_allocated = 0;" % (name, self._name), ] return code def CodeFree(self, structname): code = self.CodeClear(structname) code += TranslateList( ["free(%(structname)s->%(name)s_data);"], self.GetTranslation({"structname": structname}), ) return code def Declaration(self): dcl = [ "%s *%s_data;" % (self._ctype, self._name), "int %s_length;" % self._name, "int %s_num_allocated;" % self._name, ] return dcl def NormalizeLine(line): line = CPPCOMMENT_RE.sub("", line) line = line.strip() line = WHITESPACE_RE.sub(" ", line) return line ENTRY_NAME_RE = re.compile(r"(?P[^\[\]]+)(\[(?P.*)\])?") ENTRY_TAG_NUMBER_RE = re.compile(r"(0x)?\d+", re.I) def ProcessOneEntry(factory, newstruct, entry): optional = False array = False entry_type = "" name = "" tag = "" tag_set = None separator = "" fixed_length = "" for token in entry.split(" "): if not entry_type: if not optional and token == "optional": optional = True continue if not array and token == "array": array = True continue if not entry_type: entry_type = token continue if not name: res = ENTRY_NAME_RE.match(token) if not res: raise RpcGenError( r"""Cannot parse name: "%s" around line %d""" % (entry, LINE_COUNT) ) name = res.group("name") fixed_length = res.group("fixed_length") continue if not separator: separator = token if separator != "=": raise RpcGenError( r'''Expected "=" after name "%s" got "%s"''' % (name, token) ) continue if not tag_set: tag_set = 1 if not ENTRY_TAG_NUMBER_RE.match(token): raise RpcGenError(r'''Expected tag number: "%s"''' % (entry)) tag = int(token, 0) continue raise RpcGenError(r'''Cannot parse "%s"''' % (entry)) if not tag_set: raise RpcGenError(r'''Need tag number: "%s"''' % (entry)) # Create the right entry if entry_type == "bytes": if fixed_length: newentry = factory.EntryBytes(entry_type, name, tag, fixed_length) else: newentry = factory.EntryVarBytes(entry_type, name, tag) elif entry_type == "int" and not fixed_length: newentry = factory.EntryInt(entry_type, name, tag) elif entry_type == "int64" and not fixed_length: newentry = factory.EntryInt(entry_type, name, tag, bits=64) elif entry_type == "string" and not fixed_length: newentry = factory.EntryString(entry_type, name, tag) else: res = STRUCT_REF_RE.match(entry_type) if res: # References another struct defined in our file newentry = factory.EntryStruct(entry_type, name, tag, res.group("name")) else: raise RpcGenError('Bad type: "%s" in "%s"' % (entry_type, entry)) structs = [] if optional: newentry.MakeOptional() if array: newentry.MakeArray() newentry.SetStruct(newstruct) newentry.SetLineCount(LINE_COUNT) newentry.Verify() if array: # We need to encapsulate this entry into a struct newentry = factory.EntryArray(newentry) newentry.SetStruct(newstruct) newentry.SetLineCount(LINE_COUNT) newentry.MakeArray() newstruct.AddEntry(newentry) return structs def ProcessStruct(factory, data): tokens = data.split(" ") # First three tokens are: 'struct' 'name' '{' newstruct = factory.Struct(tokens[1]) inside = " ".join(tokens[3:-1]) tokens = inside.split(";") structs = [] for entry in tokens: entry = NormalizeLine(entry) if not entry: continue # It's possible that new structs get defined in here structs.extend(ProcessOneEntry(factory, newstruct, entry)) structs.append(newstruct) return structs C_COMMENT_START = "/*" C_COMMENT_END = "*/" C_COMMENT_START_RE = re.compile(re.escape(C_COMMENT_START)) C_COMMENT_END_RE = re.compile(re.escape(C_COMMENT_END)) C_COMMENT_START_SUB_RE = re.compile(r"%s.*$" % (re.escape(C_COMMENT_START))) C_COMMENT_END_SUB_RE = re.compile(r"%s.*$" % (re.escape(C_COMMENT_END))) C_MULTILINE_COMMENT_SUB_RE = re.compile( r"%s.*?%s" % (re.escape(C_COMMENT_START), re.escape(C_COMMENT_END)) ) CPP_CONDITIONAL_BLOCK_RE = re.compile(r"#(if( |def)|endif)") INCLUDE_RE = re.compile(r'#include (".+"|<.+>)') def GetNextStruct(filep): global CPP_DIRECT global LINE_COUNT got_struct = False have_c_comment = False data = "" while True: line = filep.readline() if not line: break LINE_COUNT += 1 line = line[:-1] if not have_c_comment and C_COMMENT_START_RE.search(line): if C_MULTILINE_COMMENT_SUB_RE.search(line): line = C_MULTILINE_COMMENT_SUB_RE.sub("", line) else: line = C_COMMENT_START_SUB_RE.sub("", line) have_c_comment = True if have_c_comment: if not C_COMMENT_END_RE.search(line): continue have_c_comment = False line = C_COMMENT_END_SUB_RE.sub("", line) line = NormalizeLine(line) if not line: continue if not got_struct: if INCLUDE_RE.match(line): CPP_DIRECT.append(line) elif CPP_CONDITIONAL_BLOCK_RE.match(line): CPP_DIRECT.append(line) elif PREPROCESSOR_DEF_RE.match(line): HEADER_DIRECT.append(line) elif not STRUCT_DEF_RE.match(line): raise RpcGenError("Missing struct on line %d: %s" % (LINE_COUNT, line)) else: got_struct = True data += line continue # We are inside the struct tokens = line.split("}") if len(tokens) == 1: data += " " + line continue if tokens[1]: raise RpcGenError("Trailing garbage after struct on line %d" % LINE_COUNT) # We found the end of the struct data += " %s}" % tokens[0] break # Remove any comments, that might be in there data = re.sub(r"/\*.*\*/", "", data) return data def Parse(factory, filep): """ Parses the input file and returns C code and corresponding header file. """ entities = [] while 1: # Just gets the whole struct nicely formatted data = GetNextStruct(filep) if not data: break entities.extend(ProcessStruct(factory, data)) return entities class CCodeGenerator(object): def __init__(self): pass @staticmethod def GuardName(name): # Use the complete provided path to the input file, with all # non-identifier characters replaced with underscores, to # reduce the chance of a collision between guard macros. return "EVENT_RPCOUT_%s_" % (NONIDENT_RE.sub("_", name).upper()) def HeaderPreamble(self, name): guard = self.GuardName(name) pre = """ /* * Automatically generated from %s */ #ifndef %s #define %s """ % ( name, guard, guard, ) if HEADER_DIRECT: for statement in HEADER_DIRECT: pre += "%s\n" % statement pre += "\n" pre += """ #include /* for ev_uint*_t */ #include """ return pre def HeaderPostamble(self, name): guard = self.GuardName(name) return "#endif /* %s */" % (guard) @staticmethod def BodyPreamble(name, header_file): global _NAME global _VERSION slash = header_file.rfind("/") if slash != -1: header_file = header_file[slash + 1 :] pre = """ /* * Automatically generated from %(name)s * by %(script_name)s/%(script_version)s. DO NOT EDIT THIS FILE. */ #include #include #include #include #include #include #include #if defined(EVENT__HAVE___func__) # ifndef __func__ # define __func__ __func__ # endif #elif defined(EVENT__HAVE___FUNCTION__) # define __func__ __FUNCTION__ #else # define __func__ __FILE__ #endif """ % { "name": name, "script_name": _NAME, "script_version": _VERSION, } for statement in CPP_DIRECT: pre += "%s\n" % statement pre += '\n#include "%s"\n\n' % header_file pre += "void event_warn(const char *fmt, ...);\n" pre += "void event_warnx(const char *fmt, ...);\n\n" return pre @staticmethod def HeaderFilename(filename): return ".".join(filename.split(".")[:-1]) + ".h" @staticmethod def CodeFilename(filename): return ".".join(filename.split(".")[:-1]) + ".gen.c" @staticmethod def Struct(name): return StructCCode(name) @staticmethod def EntryBytes(entry_type, name, tag, fixed_length): return EntryBytes(entry_type, name, tag, fixed_length) @staticmethod def EntryVarBytes(entry_type, name, tag): return EntryVarBytes(entry_type, name, tag) @staticmethod def EntryInt(entry_type, name, tag, bits=32): return EntryInt(entry_type, name, tag, bits) @staticmethod def EntryString(entry_type, name, tag): return EntryString(entry_type, name, tag) @staticmethod def EntryStruct(entry_type, name, tag, struct_name): return EntryStruct(entry_type, name, tag, struct_name) @staticmethod def EntryArray(entry): return EntryArray(entry) class CommandLine(object): def __init__(self, argv=None): """Initialize a command-line to launch event_rpcgen, as if from a command-line with CommandLine(sys.argv). If you're calling this directly, remember to provide a dummy value for sys.argv[0] """ global QUIETLY self.filename = None self.header_file = None self.impl_file = None self.factory = CCodeGenerator() parser = argparse.ArgumentParser( usage="%(prog)s [options] rpc-file [[h-file] c-file]" ) parser.add_argument("--quiet", action="store_true", default=False) parser.add_argument("rpc_file", type=argparse.FileType("r")) args, extra_args = parser.parse_known_args(args=argv) QUIETLY = args.quiet if extra_args: if len(extra_args) == 1: self.impl_file = extra_args[0].replace("\\", "/") elif len(extra_args) == 2: self.header_file = extra_args[0].replace("\\", "/") self.impl_file = extra_args[1].replace("\\", "/") else: parser.error("Spurious arguments provided") self.rpc_file = args.rpc_file if not self.impl_file: self.impl_file = self.factory.CodeFilename(self.rpc_file.name) if not self.header_file: self.header_file = self.factory.HeaderFilename(self.impl_file) if not self.impl_file.endswith(".c"): parser.error("can only generate C implementation files") if not self.header_file.endswith(".h"): parser.error("can only generate C header files") def run(self): filename = self.rpc_file.name header_file = self.header_file impl_file = self.impl_file factory = self.factory declare('Reading "%s"' % filename) with self.rpc_file: entities = Parse(factory, self.rpc_file) declare('... creating "%s"' % header_file) with open(header_file, "w") as header_fp: header_fp.write(factory.HeaderPreamble(filename)) # Create forward declarations: allows other structs to reference # each other for entry in entities: entry.PrintForwardDeclaration(header_fp) header_fp.write("\n") for entry in entities: entry.PrintTags(header_fp) entry.PrintDeclaration(header_fp) header_fp.write(factory.HeaderPostamble(filename)) declare('... creating "%s"' % impl_file) with open(impl_file, "w") as impl_fp: impl_fp.write(factory.BodyPreamble(filename, header_file)) for entry in entities: entry.PrintCode(impl_fp) def main(argv=None): try: CommandLine(argv=argv).run() return 0 except RpcGenError as e: sys.stderr.write(e) except EnvironmentError as e: if e.filename and e.strerror: sys.stderr.write("%s: %s" % (e.filename, e.strerror)) elif e.strerror: sys.stderr.write(e.strerror) else: raise return 1 if __name__ == "__main__": sys.exit(main(argv=sys.argv[1:]))