import ast
import hashlib
import collections
import lark # type: ignore
import regex # type: ignore
import synapse.exc as s_exc
import synapse.lib.ast as s_ast
import synapse.lib.coro as s_coro
import synapse.lib.cache as s_cache
import synapse.lib.datfile as s_datfile
# TL;DR: *rules* are the internal nodes of an abstract syntax tree (AST), *terminals* are the leaves
# Note: this file is coupled strongly to synapse/lib/storm.lark. Any changes to that file will probably require
# changes here
# For easier-to-understand syntax errors
terminalEnglishMap = {
'AS': 'as',
'ALLTAGS': '#',
'AND': 'and',
'BACKQUOTE': '`',
'BASEPROP': 'base property name',
'BOOL': 'boolean',
'BREAK': 'break',
'BYNAME': 'named comparison operator',
'CATCH': 'catch',
'CASEBARE': 'case value',
'CCOMMENT': 'C comment',
'CMDOPT': 'command line option',
'CMDNAME': 'command name',
'CMDRTOKN': 'An unquoted string parsed as a cmdr arg',
'CMPR': 'comparison operator',
'CMPROTHER': 'comparison operator',
'COLON': ':',
'COMMA': ',',
'COMMASPACE': ',',
'COMMANOSPACE': ',',
'CONTINUE': 'continue',
'CPPCOMMENT': 'c++ comment',
'DEFAULTCASE': 'default case',
'DOLLAR': '$',
'DOT': '.',
'DOUBLEQUOTEDSTRING': 'double-quoted string',
'ELIF': 'elif',
'EQNOSPACE': '=',
'EQSPACE': '=',
'EQUAL': '=',
'EXPRDIVIDE': '/',
'EXPRMINUS': '-',
'EXPRMODULO': '%',
'EXPRNEG': '-',
'EXPRPLUS': '+',
'EXPRPOW': '**',
'EXPRTAGSEGNOVAR': 'non-variable tag segment',
'EXPRTIMES': '*',
'FOR': 'for',
'FORMATSTRING': 'backtick-quoted format string',
'FORMATTEXT': 'text within a format string',
'FUNCTION': 'function',
'HASH': '#',
'HEXNUMBER': 'number',
'IF': 'if',
'IN': 'in',
'LBRACE': '{',
'LISTTOKN': 'unquoted list value',
'LPAR': '(',
'LSQB': '[',
'MODSET': '+= or -=',
'NONQUOTEWORD': 'unquoted value',
'NOT': 'not',
'NULL': 'null',
'NUMBER': 'number',
'OCTNUMBER': 'number',
'OR': 'or',
'PROPS': 'absolute property name',
'RBRACE': '}',
'RELNAME': 'relative property name',
'EXPRRELNAME': 'relative property name',
'RPAR': ')',
'RSQB': ']',
'RSQBNOSPACE': ']',
'SETTAGOPER': '?',
'SINGLEQUOTEDSTRING': 'single-quoted string',
'SWITCH': 'switch',
'TAGSEGNOVAR': 'non-variable tag segment',
'TRY': 'try',
'TRIPLEQUOTEDSTRING': 'triple-quoted string',
'TRYSET': '?=',
'TRYSETPLUS': '?+=',
'TRYSETMINUS': '?-=',
'UNIVNAME': 'universal property',
'EXPRUNIVNAME': 'universal property',
'VARTOKN': 'variable',
'EXPRVARTOKN': 'variable',
'VBAR': '|',
'WHILE': 'while',
'WHITETOKN': 'An unquoted string terminated by whitespace',
'WILDCARD': '*',
'WILDPROPS': 'property name potentially with wildcards',
'WILDTAGSEGNOVAR': 'tag segment potentially with asterisks',
'YIELD': 'yield',
'_ARRAYCONDSTART': '*[',
'_COLONDOLLAR': ':$',
'_COLONNOSPACE': ':',
'_DEREF': '*',
'_EDGEADDN1INIT': '+(',
'_EDGEADDN2FINI': ')+',
'_EDGEN1FINI': ')>',
'_EDGEN1INIT': '-(',
'_EDGEN2INIT': '<(',
'_EDGEN2FINI': ')-',
'_EDGEN1JOINFINI': ')+>',
'_EDGEN2JOININIT': '<+(',
'_ELSE': 'else',
'_EMBEDQUERYSTART': '${',
'_EXPRCOLONNOSPACE': ':',
'_EMIT': 'emit',
'_EMPTY': 'empty',
'_FINI': 'fini',
'_HASH': '#',
'_HASHSPACE': '#',
'_INIT': 'init',
'_LEFTJOIN': '<+-',
'_LEFTPIVOT': '<-',
'_LPARNOSPACE': '(',
'_MATCHHASH': '#',
'_MATCHHASHWILD': '#',
'_RETURN': 'return',
'_REVERSE': 'reverse',
'_RIGHTJOIN': '-+>',
'_RIGHTPIVOT': '->',
'_STOP': 'stop',
'_WALKNJOINN1': '--+>',
'_WALKNJOINN2': '<+--',
'_WALKNPIVON1': '-->',
'_WALKNPIVON2': '<--',
'$END': 'end of input',
}
AstInfo = collections.namedtuple('AstInfo', ('text', 'soff', 'eoff', 'sline', 'eline', 'scol', 'ecol', 'isterm'))
[docs]class AstConverter(lark.Transformer):
'''
Convert AST from parser into synapse AST, depth first.
If a method with a name that matches the current rule exists, that will be called, otherwise __default__ will be
used
'''
def __init__(self, text):
lark.Transformer.__init__(self)
# Keep the original text for error printing and weird subquery argv parsing
self.text = text
self.texthash = hashlib.md5(text.encode(errors='surrogatepass'), usedforsecurity=False).hexdigest()
[docs] def raiseBadSyntax(self, mesg, astinfo):
raise s_exc.BadSyntax(mesg=mesg,
# keep around for backward compatiblity
at=astinfo.soff,
line=astinfo.sline,
column=astinfo.scol,
highlight={
'hash': self.texthash,
'lines': (astinfo.sline, astinfo.eline),
'columns': (astinfo.scol, astinfo.ecol),
'offsets': (astinfo.soff, astinfo.eoff),
})
def _convert_children(self, children):
return [self._convert_child(k) for k in children]
def _convert_child(self, child):
if not isinstance(child, lark.lexer.Token):
return child
tokencls = terminalClassMap.get(child.type, s_ast.Const)
# Tokens have similar fields to meta
astinfo = self.metaToAstInfo(child, isterm=True)
return tokencls(astinfo, child.value)
def __default__(self, treedata, children, treemeta):
assert treedata in ruleClassMap, f'Unknown grammar rule: {treedata}'
return ruleClassMap[treedata](self.metaToAstInfo(treemeta), self._convert_children(children))
[docs] @lark.v_args(meta=True)
def subquery(self, meta, kids):
assert len(kids) <= 2
hasyield = (len(kids) == 2)
kid = self._convert_child(kids[-1])
kid.hasyield = hasyield
return kid
def _parseJsonToken(self, tokn):
if isinstance(tokn, lark.lexer.Token) and tokn.type == 'VARTOKN' and not tokn.value[0] in ('"', "'"):
valu = tokn.value
astinfo = self.metaToAstInfo(tokn)
try:
valu = float(valu) if '.' in valu else int(valu, 0)
except ValueError as e:
self.raiseBadSyntax('Unexpected unquoted string in JSON expression', astinfo)
return s_ast.Const(astinfo, valu)
else:
return self._convert_child(tokn)
[docs] @lark.v_args(meta=True)
def exprlist(self, meta, kids):
kids = [self._parseJsonToken(k) for k in kids]
astinfo = self.metaToAstInfo(meta, isterm=True)
return s_ast.ExprList(astinfo, kids=kids)
[docs] @lark.v_args(meta=True)
def exprdict(self, meta, kids):
kids = [self._parseJsonToken(k) for k in kids]
astinfo = self.metaToAstInfo(meta, isterm=True)
return s_ast.ExprDict(astinfo, kids=kids)
[docs] @lark.v_args(meta=True)
def yieldvalu(self, meta, kids):
kid = self._convert_child(kids[-1])
astinfo = self.metaToAstInfo(meta)
return s_ast.YieldValu(astinfo, kids=[kid])
[docs] @lark.v_args(meta=True)
def evalvalu(self, meta, kids):
return self._convert_child(kids[0])
[docs] @lark.v_args(meta=True)
def embedquery(self, meta, kids):
assert len(kids) == 1
astinfo = self.metaToAstInfo(meta)
text = kids[0].getAstText()
return s_ast.EmbedQuery(kids[0].astinfo, text, kids=kids)
[docs] @lark.v_args(meta=True)
def funccall(self, meta, kids):
astinfo = self.metaToAstInfo(meta)
argkids = []
kwargkids = []
kwnames = set()
indx = 1
kcnt = len(kids)
todo = collections.deque(kids)
namekid = todo.popleft()
while todo:
kid = self._convert_child(todo.popleft())
# look ahead for name = <valu> kwargs...
if len(todo) >= 2:
nextkid = todo[0]
if isinstance(nextkid, lark.lexer.Token) and nextkid.type in ('EQNOSPACE', 'EQUAL', 'EQSPACE'):
todo.popleft()
valukid = self._convert_child(todo.popleft())
if kid.valu in kwnames:
self.raiseBadSyntax(f'Duplicate keyword argument "{kid.valu}" in function call', kid.astinfo)
kwnames.add(kid.valu)
kwargkids.append(s_ast.CallKwarg(kid.astinfo, (kid, valukid)))
continue
if kwargkids:
self.raiseBadSyntax('Positional argument follows keyword argument in function call', kid.astinfo)
argkids.append(kid)
args = s_ast.CallArgs(astinfo, kids=argkids)
kwargs = s_ast.CallKwargs(astinfo, kids=kwargkids)
return s_ast.FuncCall(astinfo, kids=[namekid, args, kwargs])
[docs] @lark.v_args(meta=True)
def varlist(self, meta, kids):
kids = self._convert_children(kids)
astinfo = self.metaToAstInfo(meta)
return s_ast.VarList(astinfo, [k.valu for k in kids])
[docs] @lark.v_args(meta=True)
def operrelprop_pivot(self, meta, kids, isjoin=False):
kids = self._convert_children(kids)
astinfo = self.metaToAstInfo(meta)
relprop, rest = kids[0], kids[1:]
if not rest:
return s_ast.PropPivotOut(astinfo, kids=kids, isjoin=isjoin)
pval = s_ast.RelPropValue(astinfo, kids=(relprop,))
return s_ast.PropPivot(astinfo, kids=(pval, *kids[1:]), isjoin=isjoin)
[docs] @lark.v_args(meta=True)
def operrelprop_join(self, meta, kids):
return self.operrelprop_pivot(meta, kids, isjoin=True)
[docs] @lark.v_args(meta=True)
def stormcmdargs(self, meta, kids):
newkids = []
for kid in kids:
if isinstance(kid, lark.lexer.Token) and kid.type == 'EQNOSPACE':
continue
newkids.append(self._convert_child(kid))
astinfo = self.metaToAstInfo(meta)
return s_ast.List(astinfo, kids=newkids)
[docs] @lark.v_args(meta=True)
def funcargs(self, meta, kids):
'''
A list of function parameters (as part of a function definition)
'''
kids = self._convert_children(kids)
astinfo = self.metaToAstInfo(meta)
newkids = []
kwnames = set()
kwfound = False
todo = collections.deque(kids)
while todo:
kid = todo.popleft()
if kid.valu in kwnames:
mesg = f'Duplicate parameter "{kid.valu}" in function definition'
self.raiseBadSyntax(mesg, kid.astinfo)
kwnames.add(kid.valu)
# look ahead for name = <default> kwarg decls
if len(todo) >= 2:
nextkid = todo[0]
if isinstance(nextkid, s_ast.Const) and nextkid.valu == '=':
todo.popleft()
valukid = todo.popleft()
kwfound = True
newkids.append(s_ast.CallKwarg(kid.astinfo, (kid, valukid)))
continue
if kwfound:
mesg = f'Positional parameter "{kid.valu}" follows keyword parameter in definition'
self.raiseBadSyntax(mesg, astinfo)
newkids.append(kid)
return s_ast.FuncArgs(astinfo, newkids)
[docs] @lark.v_args(meta=True)
def cmdrargs(self, meta, kids):
argv = []
indx = 0
kcnt = len(kids)
while indx < kcnt:
kid = kids[indx]
indx += 1
if isinstance(kid, s_ast.SubQuery):
argv.append(kid.text)
continue
# this one should never happen, but is here in case
if isinstance(kid, s_ast.Const): # pragma: no cover
argv.append(kid.valu)
continue
if isinstance(kid, lark.lexer.Token):
if kid == '=':
argv[-1] += kid
if kcnt >= indx:
nextkid = kids[indx]
if isinstance(nextkid, s_ast.SubQuery):
argv[-1] += nextkid.text
elif isinstance(nextkid, s_ast.Const): #pragma: no cover
argv[-1] += nextkid.valu
else:
argv[-1] += str(nextkid)
indx += 1
continue
else:
argv.append(str(kid))
continue
# pragma: no cover
mesg = f'Unhandled AST node type in cmdrargs: {kid!r}'
self.raiseBadSyntax(mesg, kid.astinfo)
return argv
[docs] @lark.v_args(meta=True)
def varderef(self, meta, kids):
assert kids and len(kids) in (3, 4)
astinfo = self.metaToAstInfo(meta)
if kids[2] == '$':
tokencls = terminalClassMap.get(kids[3].type, s_ast.Const)
kidfo = self.metaToAstInfo(kids[3], isterm=True)
newkid = s_ast.VarValue(kidfo, kids=[tokencls(kids[3], kids[3])])
else:
newkid = self._convert_child(kids[2])
return s_ast.VarDeref(astinfo, kids=(kids[0], newkid))
[docs] @lark.v_args(meta=True)
def switchcase(self, meta, kids):
astinfo = self.metaToAstInfo(meta)
newkids = []
it = iter(kids)
varvalu = next(it)
newkids.append(varvalu)
for casekid, sqkid in zip(it, it):
subquery = self._convert_child(sqkid)
if casekid.type == 'DEFAULTCASE':
caseinfo = self.metaToAstInfo(casekid)
caseentry = s_ast.CaseEntry(caseinfo, kids=[subquery])
else:
casekid = self._convert_child(casekid)
caseentry = s_ast.CaseEntry(casekid.astinfo, kids=[casekid, subquery])
newkids.append(caseentry)
return s_ast.SwitchCase(astinfo, newkids)
[docs] @lark.v_args(meta=True)
def liftreverse(self, meta, kids):
assert len(kids) == 1
astinfo = self.metaToAstInfo(meta)
kids[0].reverseLift(astinfo)
return kids[0]
with s_datfile.openDatFile('synapse.lib/storm.lark') as larkf:
_grammar = larkf.read().decode()
LarkParser = lark.Lark(_grammar, regex=True, start=['query', 'lookup', 'cmdrargs', 'evalvalu', 'search'],
maybe_placeholders=False, propagate_positions=True, parser='lalr')
[docs]class Parser:
'''
Storm query parser
'''
def __init__(self, text, offs=0):
self.offs = offs
assert text is not None
self.text = text
self.size = len(self.text)
def _larkToSynExc(self, e):
'''
Convert lark exception to synapse BadSyntax exception
'''
mesg = regex.split('[\n]', str(e))[0]
at = len(self.text)
line = None
column = None
token = None
if isinstance(e, lark.exceptions.UnexpectedToken):
expected = sorted(set(terminalEnglishMap[t] for t in e.expected))
at = e.pos_in_stream
line = e.line
column = e.column
token = e.token.value
valu = terminalEnglishMap.get(e.token.type, e.token.value)
mesg = f"Unexpected token '{valu}' at line {line}, column {column}," \
f' expecting one of: {", ".join(expected)}'
elif isinstance(e, lark.exceptions.VisitError):
# Lark unhelpfully wraps an exception raised from AstConverter in a VisitError. Unwrap it.
origexc = e.orig_exc
if not isinstance(origexc, s_exc.SynErr):
raise e.orig_exc # pragma: no cover
origexc.errinfo['text'] = self.text
return s_exc.BadSyntax(**origexc.errinfo)
elif isinstance(e, lark.exceptions.UnexpectedCharacters): # pragma: no cover
expected = sorted(set(terminalEnglishMap[t] for t in e.allowed))
mesg += f'. Expecting one of: {", ".join(expected)}'
at = e.pos_in_stream
line = e.line
column = e.column
elif isinstance(e, lark.exceptions.UnexpectedEOF): # pragma: no cover
expected = sorted(set(terminalEnglishMap[t] for t in e.expected))
mesg += ' ' + ', '.join(expected)
line = e.line
column = e.column
return s_exc.BadSyntax(at=at, text=self.text, mesg=mesg, line=line, column=column, token=token)
[docs] def eval(self):
try:
tree = LarkParser.parse(self.text, start='evalvalu')
newtree = AstConverter(self.text).transform(tree)
except lark.exceptions.LarkError as e:
raise self._larkToSynExc(e) from None
newtree.text = self.text
return newtree
[docs] def query(self):
'''
Parse the storm query
Returns (s_ast.Query): instance of parsed query
'''
try:
tree = LarkParser.parse(self.text, start='query')
newtree = AstConverter(self.text).transform(tree)
except lark.exceptions.LarkError as e:
raise self._larkToSynExc(e) from None
newtree.text = self.text
return newtree
[docs] def lookup(self):
try:
tree = LarkParser.parse(self.text, start='lookup')
newtree = AstConverter(self.text).transform(tree)
except lark.exceptions.LarkError as e:
raise self._larkToSynExc(e) from None
newtree.text = self.text
return newtree
[docs] def search(self):
try:
tree = LarkParser.parse(self.text, start='search')
newtree = AstConverter(self.text).transform(tree)
except lark.exceptions.LarkError as e:
raise self._larkToSynExc(e) from None
newtree.text = self.text
return newtree
[docs] def cmdrargs(self):
'''
Parse command args that might have storm queries as arguments
'''
try:
tree = LarkParser.parse(self.text, start='cmdrargs')
return AstConverter(self.text).transform(tree)
except lark.exceptions.LarkError as e:
raise self._larkToSynExc(e) from None
[docs]def parseQuery(text, mode='storm'):
'''
Parse a storm query and return the Lark AST. Cached here to speed up unit tests
'''
if mode == 'lookup':
return Parser(text).lookup()
if mode == 'autoadd':
look = Parser(text).lookup()
look.autoadd = True
return look
if mode == 'search':
return Parser(text).search()
return Parser(text).query()
[docs]def parseEval(text):
return Parser(text).eval()
async def _forkedParseQuery(args):
return await s_coro._parserforked(parseQuery, args[0], mode=args[1])
async def _forkedParseEval(text):
return await s_coro._parserforked(parseEval, text)
evalcache = s_cache.FixedCache(_forkedParseEval, size=100)
querycache = s_cache.FixedCache(_forkedParseQuery, size=100)
[docs]def massage_vartokn(astinfo, x):
return s_ast.Const(astinfo, '' if not x else (x[1:-1] if x[0] == "'" else (unescape(x) if x[0] == '"' else x)))
# For AstConverter, one-to-one replacements from lark to synapse AST
terminalClassMap = {
'ALLTAGS': lambda astinfo, _: s_ast.TagMatch(astinfo, ''),
'BREAK': lambda astinfo, _: s_ast.BreakOper(astinfo),
'CONTINUE': lambda astinfo, _: s_ast.ContinueOper(astinfo),
'DOUBLEQUOTEDSTRING': lambda astinfo, x: s_ast.Const(astinfo, unescape(x)), # drop quotes and handle escape characters
'FORMATTEXT': lambda astinfo, x: s_ast.Const(astinfo, format_unescape(x)), # handle escape characters
'TRIPLEQUOTEDSTRING': lambda astinfo, x: s_ast.Const(astinfo, x[3:-3]), # drop the triple 's
'NUMBER': lambda astinfo, x: s_ast.Const(astinfo, s_ast.parseNumber(x)),
'HEXNUMBER': lambda astinfo, x: s_ast.Const(astinfo, s_ast.parseNumber(x)),
'OCTNUMBER': lambda astinfo, x: s_ast.Const(astinfo, s_ast.parseNumber(x)),
'BOOL': lambda astinfo, x: s_ast.Bool(astinfo, x == 'true'),
'NULL': lambda astinfo, x: s_ast.Const(astinfo, None),
'SINGLEQUOTEDSTRING': lambda astinfo, x: s_ast.Const(astinfo, x[1:-1]), # drop quotes
'NONQUOTEWORD': massage_vartokn,
'VARTOKN': massage_vartokn,
'EXPRVARTOKN': massage_vartokn,
}
# For AstConverter, one-to-one replacements from lark to synapse AST
ruleClassMap = {
'abspropcond': s_ast.AbsPropCond,
'argvquery': s_ast.ArgvQuery,
'arraycond': s_ast.ArrayCond,
'andexpr': s_ast.AndCond,
'baresubquery': s_ast.SubQuery,
'catchblock': s_ast.CatchBlock,
'condsubq': s_ast.SubqCond,
'dollarexpr': s_ast.DollarExpr,
'edgeaddn1': s_ast.EditEdgeAdd,
'edgedeln1': s_ast.EditEdgeDel,
'edgeaddn2': lambda astinfo, kids: s_ast.EditEdgeAdd(astinfo, kids, n2=True),
'edgedeln2': lambda astinfo, kids: s_ast.EditEdgeDel(astinfo, kids, n2=True),
'editnodeadd': s_ast.EditNodeAdd,
'editparens': s_ast.EditParens,
'emit': s_ast.Emit,
'initblock': s_ast.InitBlock,
'emptyblock': s_ast.EmptyBlock,
'finiblock': s_ast.FiniBlock,
'formname': s_ast.FormName,
'editpropdel': lambda astinfo, kids: s_ast.EditPropDel(astinfo, kids[1:]),
'editpropset': s_ast.EditPropSet,
'edittagadd': s_ast.EditTagAdd,
'edittagdel': lambda astinfo, kids: s_ast.EditTagDel(astinfo, kids[1:]),
'edittagpropset': s_ast.EditTagPropSet,
'edittagpropdel': lambda astinfo, kids: s_ast.EditTagPropDel(astinfo, kids[1:]),
'editunivdel': lambda astinfo, kids: s_ast.EditUnivDel(astinfo, kids[1:]),
'editunivset': s_ast.EditPropSet,
'expror': s_ast.ExprOrNode,
'exprand': s_ast.ExprAndNode,
'exprnot': s_ast.UnaryExprNode,
'exprunary': s_ast.UnaryExprNode,
'exprcmp': s_ast.ExprNode,
'exprpow': s_ast.ExprNode,
'exprproduct': s_ast.ExprNode,
'exprsum': s_ast.ExprNode,
'filtoper': s_ast.FiltOper,
'filtopermust': lambda astinfo, kids: s_ast.FiltOper(astinfo, [s_ast.Const(astinfo, '+')] + kids),
'filtopernot': lambda astinfo, kids: s_ast.FiltOper(astinfo, [s_ast.Const(astinfo, '-')] + kids),
'forloop': s_ast.ForLoop,
'formatstring': s_ast.FormatString,
'formjoin_formpivot': lambda astinfo, kids: s_ast.FormPivot(astinfo, kids, isjoin=True),
'formjoin_pivotout': lambda astinfo, _: s_ast.PivotOut(astinfo, isjoin=True),
'formjoinin_pivotin': lambda astinfo, kids: s_ast.PivotIn(astinfo, kids, isjoin=True),
'formjoinin_pivotinfrom': lambda astinfo, kids: s_ast.PivotInFrom(astinfo, kids, isjoin=True),
'formpivot_': s_ast.FormPivot,
'formpivot_pivotout': s_ast.PivotOut,
'formpivot_pivottotags': s_ast.PivotToTags,
'formpivot_jointags': lambda astinfo, kids: s_ast.PivotToTags(astinfo, kids, isjoin=True),
'formpivotin_': s_ast.PivotIn,
'formpivotin_pivotinfrom': s_ast.PivotInFrom,
'formtagprop': s_ast.FormTagProp,
'hasabspropcond': s_ast.HasAbsPropCond,
'hasrelpropcond': s_ast.HasRelPropCond,
'hastagpropcond': s_ast.HasTagPropCond,
'ifstmt': s_ast.IfStmt,
'ifclause': s_ast.IfClause,
'kwarg': lambda astinfo, kids: s_ast.CallKwarg(astinfo, kids=tuple(kids)),
'liftbytag': s_ast.LiftTag,
'liftformtag': s_ast.LiftFormTag,
'liftprop': s_ast.LiftProp,
'liftpropby': s_ast.LiftPropBy,
'lifttagtag': s_ast.LiftTagTag,
'liftbyarray': s_ast.LiftByArray,
'liftbytagprop': s_ast.LiftTagProp,
'liftbyformtagprop': s_ast.LiftFormTagProp,
'looklist': s_ast.LookList,
'lookup': s_ast.Lookup,
'n1join': lambda astinfo, kids: s_ast.N1Walk(astinfo, kids, isjoin=True),
'n2join': lambda astinfo, kids: s_ast.N2Walk(astinfo, kids, isjoin=True),
'n1walk': s_ast.N1Walk,
'n2walk': s_ast.N2Walk,
'n1walknjoin': lambda astinfo, kids: s_ast.N1WalkNPivo(astinfo, kids, isjoin=True),
'n2walknjoin': lambda astinfo, kids: s_ast.N2WalkNPivo(astinfo, kids, isjoin=True),
'n1walknpivo': s_ast.N1WalkNPivo,
'n2walknpivo': s_ast.N2WalkNPivo,
'notcond': s_ast.NotCond,
'opervarlist': s_ast.VarListSetOper,
'orexpr': s_ast.OrCond,
'query': s_ast.Query,
'rawpivot': s_ast.RawPivot,
'return': s_ast.Return,
'relprop': lambda astinfo, kids: s_ast.RelProp(astinfo, [s_ast.Const(k.astinfo, k.valu.lstrip(':')) if isinstance(k, s_ast.Const) else k for k in kids]),
'relpropcond': s_ast.RelPropCond,
'relpropvalu': lambda astinfo, kids: s_ast.RelPropValue(astinfo, [s_ast.Const(k.astinfo, k.valu.lstrip(':')) if isinstance(k, s_ast.Const) else k for k in kids]),
'relpropvalue': s_ast.RelPropValue,
'search': s_ast.Search,
'setitem': lambda astinfo, kids: s_ast.SetItemOper(astinfo, [kids[0], kids[1], kids[3]]),
'setvar': s_ast.SetVarOper,
'stop': s_ast.Stop,
'stormcmd': lambda astinfo, kids: s_ast.CmdOper(astinfo, kids=kids if len(kids) == 2 else (kids[0], s_ast.Const(astinfo, tuple()))),
'stormfunc': s_ast.Function,
'tagcond': s_ast.TagCond,
'tagname': s_ast.TagName,
'tagmatch': s_ast.TagMatch,
'tagprop': s_ast.TagProp,
'tagvalu': s_ast.TagValue,
'tagpropvalu': s_ast.TagPropValue,
'tagvalucond': s_ast.TagValuCond,
'tagpropcond': s_ast.TagPropCond,
'trycatch': s_ast.TryCatch,
'univprop': s_ast.UnivProp,
'univpropvalu': s_ast.UnivPropValue,
'valulist': s_ast.List,
'vareval': s_ast.VarEvalOper,
'varvalue': s_ast.VarValue,
'whileloop': s_ast.WhileLoop,
'wordtokn': lambda astinfo, kids: s_ast.Const(astinfo, ''.join([str(k.valu) for k in kids]))
}
escape_re = regex.compile(r"(?<!\\)((\\\\)*)'")
[docs]def unescape(valu):
'''
Parse a string for backslash-escaped characters and omit them.
The full list of escaped characters can be found at
https://docs.python.org/3/reference/lexical_analysis.html#string-and-bytes-literals
'''
try:
ret = ast.literal_eval(valu)
except (SyntaxError, ValueError) as e:
mesg = f"Invalid character in string {repr(valu)}: {e}"
raise s_exc.BadSyntax(mesg=mesg, valu=repr(valu)) from None
assert isinstance(ret, str)
return ret
# TODO: use existing storm parser and remove this
CmdStringGrammar = r'''
%import common.WS -> _WS
%import common.ESCAPED_STRING
cmdstring: _WS? valu [/.+/]
valu: alist | DOUBLEQUOTEDSTRING | SINGLEQUOTEDSTRING | JUSTCHARS
DOUBLEQUOTEDSTRING: ESCAPED_STRING
SINGLEQUOTEDSTRING: /'[^']*'/
alist: "(" _WS? valu (_WS? "," _WS? valu)* _WS? ")"
// Disallow trailing comma
JUSTCHARS: /[^()=\[\]{}'"\s]*[^,()=\[\]{}'"\s]/
'''
CmdStringParser = lark.Lark(CmdStringGrammar,
start='cmdstring',
regex=True,
propagate_positions=True)
[docs]def parse_cmd_string(text, off):
'''
Parse a command line string which may be quoted.
'''
tree = CmdStringParser.parse(text[off:])
valu, newoff = CmdStringer().transform(tree)
return valu, off + newoff
[docs]@lark.v_args(meta=True)
class CmdStringer(lark.Transformer):
[docs] def valu(self, meta, kids):
assert len(kids) == 1
kid = kids[0]
if isinstance(kid, lark.lexer.Token):
if kid.type in ('DOUBLEQUOTEDSTRING', 'SINGLEQUOTEDSTRING'):
valu = kid.value[1:-1]
else:
valu = kid.value
try:
intval = int(valu)
valu = intval
except Exception:
pass
else:
valu = kid[0]
return valu, meta.end_pos
[docs] def cmdstring(self, meta, kids):
return kids[0]
[docs] def alist(self, meta, kids):
return [k[0] for k in kids], meta.end_pos