def ToLValue(node):
# type: (arith_expr_t) -> sh_lhs_expr_t
"""Determine if a node is a valid L-value by whitelisting tags.
Valid:
x = y
a[1] = y
Invalid:
a[0][0] = y
"""
UP_node = node
with tagswitch(node) as case:
if case(arith_expr_e.VarRef):
node = cast(arith_expr__VarRef, UP_node)
# For consistency with osh/cmd_parse.py, append a span_id.
# TODO: (( a[ x ] = 1 )) and a[x]=1 should use different LST nodes.
n = sh_lhs_expr.Name(node.token.val)
n.spids.append(node.token.span_id)
return n
elif case(arith_expr_e.Binary):
node = cast(arith_expr__Binary, UP_node)
if (node.op_id == Id.Arith_LBracket
and node.left.tag_() == arith_expr_e.VarRef):
left = cast(arith_expr__VarRef, node.left)
return sh_lhs_expr.IndexedName(left.token.val, node.right)
# But a[0][0] = 1 is NOT valid.
return None
def Eval(self, node):
# type: (command_t) -> None
UP_node = node
with tagswitch(node) as case:
if case(command_e.Simple):
node = cast(command__Simple, UP_node)
# Need splitter for this.
if 0:
cmd_val = self.word_ev.EvalWordSequence2(node.words,
allow_assign=True)
for arg in cmd_val.argv:
log('arg %s', arg)
for w in node.words:
val = self.word_ev.EvalWordToString(w)
# TODO: how to print repr() in C++?
log('arg %d', val.tag_())
elif case(command_e.DParen):
node = cast(command__DParen, UP_node)
a = self.arith_ev.Eval(node.child)
# TODO: how to print repr() in C++?
log('arith val %d', a.tag_())
else:
log('Unhandled node %s', NewStr(command_str(node.tag_())))
def CommandId(w):
# type: (word_t) -> Id_t
UP_w = w
with tagswitch(w) as case:
if case(word_e.Token):
tok = cast(Token, UP_w)
return tok.id
elif case(word_e.Compound):
w = cast(compound_word, UP_w)
# Has to be a single literal part
if len(w.parts) != 1:
return Id.Word_Compound
token_type = _LiteralId(w.parts[0])
if token_type == Id.Undefined_Tok:
return Id.Word_Compound
elif token_type in (Id.Lit_LBrace, Id.Lit_RBrace, Id.Lit_Equals,
Id.ControlFlow_Return):
# OSH and Oil recognize: { }
# Oil recognizes: = return
return token_type
token_kind = consts.GetKind(token_type)
if token_kind == Kind.KW:
return token_type
return Id.Word_Compound
else:
raise AssertionError(w.tag_())
def Push(self, redirects, waiter):
# type: (List[redirect_t], Waiter) -> bool
#log('> fd_state.Push %s', redirects)
new_frame = _FdFrame()
self.stack.append(new_frame)
self.cur_frame = new_frame
for r in redirects:
# TODO: Could we use inheritance to make this cheaper?
UP_r = r
with tagswitch(r) as case:
if case(redirect_e.Path):
r = cast(redirect__Path, UP_r)
op_spid = r.op_spid
elif case(redirect_e.FileDesc):
r = cast(redirect__FileDesc, UP_r)
op_spid = r.op_spid
elif case(redirect_e.HereDoc):
r = cast(redirect__HereDoc, UP_r)
op_spid = r.op_spid
else:
raise AssertionError()
#log('apply %s', r)
self.errfmt.PushLocation(op_spid)
try:
if not self._ApplyRedirect(r, waiter):
return False # for bad descriptor
finally:
self.errfmt.PopLocation()
#log('done applying %d redirects', len(redirects))
return True
def GetJoinChar(self):
# type: () -> str
"""
For decaying arrays by joining, eg. "$@" -> $@.
array
"""
# https://www.gnu.org/software/bash/manual/bashref.html#Special-Parameters
# http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_05_02
# "When the expansion occurs within a double-quoted string (see
# Double-Quotes), it shall expand to a single field with the value of
# each parameter separated by the first character of the IFS variable, or
# by a <space> if IFS is unset. If IFS is set to a null string, this is
# not equivalent to unsetting it; its first character does not exist, so
# the parameter values are concatenated."
val = self.mem.GetValue('IFS') # type: value_t
UP_val = val
with tagswitch(val) as case:
if case(value_e.Undef):
return ' '
elif case(value_e.Str):
val = cast(value__Str, UP_val)
if len(val.s):
return val.s[0]
else:
return ''
else:
# TODO: Raise proper error
raise AssertionError("IFS shouldn't be an array")
def OnShAssignment(self, lval, op, val, flags, which_scopes):
# type: (lvalue_t, assign_op_t, value_t, int, scope_t) -> None
buf = self._ShTraceBegin()
if not buf:
return
left = '?'
UP_lval = lval
with tagswitch(lval) as case:
if case(lvalue_e.Named):
lval = cast(lvalue__Named, UP_lval)
left = lval.name
elif case(lvalue_e.Indexed):
lval = cast(lvalue__Indexed, UP_lval)
left = '%s[%d]' % (lval.name, lval.index)
elif case(lvalue_e.Keyed):
lval = cast(lvalue__Keyed, UP_lval)
left = '%s[%s]' % (lval.name, qsn.maybe_shell_encode(lval.key))
buf.write(left)
# Only two possibilities here
buf.write('+=' if op == assign_op_e.PlusEqual else '=')
_PrintShValue(val, buf)
buf.write('\n')
self.f.write(buf.getvalue())
def _EvalLhsArith(node, mem, arith_ev):
# type: (sh_lhs_expr_t, Mem, ArithEvaluator) -> lvalue_t
"""sh_lhs_expr -> lvalue.
Very similar to EvalLhs above in core/cmd_exec.
"""
assert isinstance(node, sh_lhs_expr_t), node
UP_node = node
with tagswitch(node) as case:
if case(sh_lhs_expr_e.Name): # (( i = 42 ))
node = cast(sh_lhs_expr__Name, UP_node)
lval = lvalue.Named(node.name) # type: lvalue_t
# TODO: location info. Use the = token?
#lval.spids.append(spid)
elif case(sh_lhs_expr_e.IndexedName): # (( a[42] = 42 ))
node = cast(sh_lhs_expr__IndexedName, UP_node)
# The index of MaybeStrArray needs to be coerced to int, but not the
# index of an AssocArray.
if mem.IsAssocArray(node.name, scope_e.Dynamic):
key = arith_ev.EvalWordToString(node.index)
lval = lvalue.Keyed(node.name, key)
else:
index = arith_ev.EvalToInt(node.index)
lval = lvalue.Indexed(node.name, index)
# TODO: location info. Use the = token?
#lval.spids.append(node.spids[0])
else:
raise AssertionError(node.tag_())
return lval
def _PrintShValue(val, buf):
# type: (value_t, mylib.BufWriter) -> None
"""Using maybe_shell_encode() for legacy xtrace_details."""
# NOTE: This is a bit like _PrintVariables for declare -p
result = '?'
UP_val = val
with tagswitch(val) as case:
if case(value_e.Str):
val = cast(value__Str, UP_val)
result = qsn.maybe_shell_encode(val.s)
elif case(value_e.MaybeStrArray):
val = cast(value__MaybeStrArray, UP_val)
parts = ['(']
for s in val.strs:
parts.append(qsn.maybe_shell_encode(s))
parts.append(')')
result = ' '.join(parts)
elif case(value_e.AssocArray):
val = cast(value__AssocArray, UP_val)
parts = ['(']
for k, v in iteritems(val.d):
parts.append(
'[%s]=%s' %
(qsn.maybe_shell_encode(k), qsn.maybe_shell_encode(v)))
parts.append(')')
result = ' '.join(parts)
buf.write(result)
def BoolId(w):
# type: (word_t) -> Id_t
UP_w = w
with tagswitch(w) as case:
if case(word_e.String): # for test/[
w = cast(word__String, UP_w)
return w.id
elif case(word_e.Token):
tok = cast(Token, UP_w)
return tok.id
elif case(word_e.Compound):
w = cast(compound_word, UP_w)
if len(w.parts) != 1:
return Id.Word_Compound
token_type = _LiteralId(w.parts[0])
if token_type == Id.Undefined_Tok:
return Id.Word_Compound # It's a regular word
# This is outside the BoolUnary/BoolBinary namespace, but works the same.
if token_type in (Id.KW_Bang, Id.Lit_DRightBracket):
return token_type # special boolean "tokens"
token_kind = consts.GetKind(token_type)
if token_kind in (Kind.BoolUnary, Kind.BoolBinary):
return token_type # boolean operators
return Id.Word_Compound
else:
# I think Empty never happens in this context?
raise AssertionError(w.tag_())
def LeftMostSpanForWord(w):
# type: (word_t) -> int
UP_w = w
with tagswitch(w) as case:
if case(word_e.Compound):
w = cast(compound_word, UP_w)
if len(w.parts):
return LeftMostSpanForPart(w.parts[0])
else:
# This is possible for empty brace sub alternative {a,b,}
return runtime.NO_SPID
elif case(word_e.Token):
tok = cast(Token, UP_w)
return tok.span_id
elif case(word_e.Empty):
return runtime.NO_SPID
elif case(word_e.BracedTree):
w = cast(word__BracedTree, UP_w)
# This should always have one part?
return LeftMostSpanForPart(w.parts[0])
elif case(word_e.String):
w = cast(word__String, UP_w)
return w.span_id # See _StringWordEmitter in osh/builtin_bracket.py
else:
raise AssertionError(w.tag_())
def _SetToArg(action, suffix, arg_r, out):
# type: (SetToArgAction, Optional[str], Reader, _Attributes) -> bool
"""
Perform the action.
"""
if suffix: # for the ',' in -d,
arg = suffix
else:
arg_r.Next()
arg = arg_r.Peek()
if arg is None:
e_usage('expected argument to %r' % ('-' + action.name),
span_id=arg_r.SpanId())
# e.g. spec.LongFlag('--format', ['text', 'html'])
# Should change to arg.Enum([...])
with tagswitch(action.flag_type) as case:
if case(flag_type_e.Enum):
alts = cast(flag_type__Enum, action.flag_type).alts
if arg not in alts:
e_usage('got invalid argument %r to %r, expected one of: %s' %
(arg, ('-' + action.name), ', '.join(alts)),
span_id=arg_r.SpanId())
val = value.Str(arg) # type: value_t
elif case(flag_type_e.Str):
val = value.Str(arg)
elif case(flag_type_e.Int):
try:
i = int(arg)
except ValueError:
e_usage('expected integer after %s, got %r' %
('-' + action.name, arg),
span_id=arg_r.SpanId())
# So far all our int values are > 0, so use -1 as the 'unset' value
if i < 0:
e_usage('got invalid integer for %s: %s' %
('-' + action.name, arg),
span_id=arg_r.SpanId())
val = value.Int(i)
elif case(flag_type_e.Float):
try:
val = value.Float(float(arg))
except ValueError:
e_usage('expected number after %r, got %r' %
('-' + action.name, arg),
span_id=arg_r.SpanId())
else:
raise AssertionError()
out.Set(action.name, val)
return action.quit_parsing_flags
def _VarRefOrWord(node, dynamic_arith):
# type: (arith_expr_t, bool) -> bool
with tagswitch(node) as case:
if case(arith_expr_e.VarRef):
return True
elif case(arith_expr_e.Word):
if dynamic_arith:
return True
return False
def _RightMostSpanForPart(part):
# type: (word_part_t) -> int
UP_part = part
with tagswitch(part) as case:
if case(word_part_e.ShArrayLiteral):
part = cast(sh_array_literal, UP_part)
# TODO: Return )
return LeftMostSpanForWord(part.words[0]) # Hm this is a=(1 2 3)
elif case(word_part_e.Literal):
# Just use the token
tok = cast(Token, UP_part)
return tok.span_id
elif case(word_part_e.EscapedLiteral):
part = cast(word_part__EscapedLiteral, UP_part)
return part.token.span_id
elif case(word_part_e.SingleQuoted):
part = cast(single_quoted, UP_part)
return part.spids[1] # right '
elif case(word_part_e.DoubleQuoted):
part = cast(double_quoted, UP_part)
return part.spids[1] # right "
elif case(word_part_e.SimpleVarSub):
part = cast(simple_var_sub, UP_part)
return part.token.span_id
elif case(word_part_e.BracedVarSub):
part = cast(braced_var_sub, UP_part)
spid = part.spids[1] # right }
assert spid != runtime.NO_SPID
return spid
elif case(word_part_e.CommandSub):
part = cast(command_sub, UP_part)
return part.spids[1]
elif case(word_part_e.TildeSub):
return runtime.NO_SPID
elif case(word_part_e.ArithSub):
part = cast(word_part__ArithSub, UP_part)
return part.spids[1]
elif case(word_part_e.ExtGlob):
part = cast(word_part__ExtGlob, UP_part)
return part.spids[1]
# TODO: Do Splice and FuncCall need it?
else:
raise AssertionError(part.tag_())
def SpanForArithExpr(node):
# type: (arith_expr_t) -> int
UP_node = node
with tagswitch(node) as case:
if case(arith_expr_e.VarRef):
token = cast(Token, UP_node)
return token.span_id
elif case(arith_expr_e.Word):
w = cast(compound_word, UP_node)
return word_.LeftMostSpanForWord(w)
return runtime.NO_SPID
def _ExpandPart(
parts, # type: List[word_part_t]
first_alt_index, # type: int
suffixes, # type: List[List[word_part_t]]
):
# type: (...) -> List[List[word_part_t]]
"""Mutually recursive with _BraceExpand.
Args:
parts: input parts
first_alt_index: index of the first BracedTuple
suffixes: List of suffixes to append.
"""
out = [] # type: List[List[word_part_t]]
prefix = parts[:first_alt_index]
expand_part = parts[first_alt_index]
UP_part = expand_part
with tagswitch(expand_part) as case:
if case(word_part_e.BracedTuple):
expand_part = cast(word_part__BracedTuple, UP_part)
# Call _BraceExpand on each of the inner words too!
expanded_alts = [] # type: List[List[word_part_t]]
for w in expand_part.words:
expanded_alts.extend(_BraceExpand(w.parts))
for alt_parts in expanded_alts:
for suffix in suffixes:
out_parts = [] # type: List[word_part_t]
out_parts.extend(prefix)
out_parts.extend(alt_parts)
out_parts.extend(suffix)
out.append(out_parts)
elif case(word_part_e.BracedRange):
expand_part = cast(word_part__BracedRange, UP_part)
# Not mutually recursive with _BraceExpand
strs = _RangeStrings(expand_part)
for s in strs:
for suffix in suffixes:
out_parts_ = [] # type: List[word_part_t]
out_parts_.extend(prefix)
# Preserve span_id from the original
t = Token(Id.Lit_Chars, expand_part.spids[0], s)
out_parts_.append(t)
out_parts_.extend(suffix)
out.append(out_parts_)
else:
raise AssertionError()
return out
def SpanForArithExpr(node):
# type: (arith_expr_t) -> int
UP_node = node
with tagswitch(node) as case:
if case(arith_expr_e.VarRef):
# TODO: VarRef should store a token instead of a string!
return runtime.NO_SPID
elif case(arith_expr_e.ArithWord):
node = cast(arith_expr__ArithWord, UP_node)
return word_.LeftMostSpanForWord(node.w)
return runtime.NO_SPID
def OnMatch(self, prefix, suffix, arg_r, out):
# type: (Optional[str], Optional[str], Reader, _Attributes) -> bool
"""Called when the flag matches."""
if suffix: # for the ',' in -d,
arg = suffix
else:
arg_r.Next()
arg = arg_r.Peek()
if arg is None:
e_usage('expected argument to %r' % ('-' + self.name),
span_id=arg_r.SpanId())
# e.g. spec.LongFlag('--format', ['text', 'html'])
# Should change to arg.Enum([...])
with tagswitch(self.flag_type) as case:
if case(flag_type_e.Enum):
alts = cast(flag_type__Enum, self.flag_type).alts
if arg not in alts:
e_usage(
'got invalid argument %r to %r, expected one of: %s' %
(arg, ('-' + self.name), ', '.join(alts)),
span_id=arg_r.SpanId())
val = value.Str(arg) # type: value_t
elif case(flag_type_e.Str):
val = value.Str(arg)
elif case(flag_type_e.Int):
try:
val = value.Int(int(arg))
except ValueError:
e_usage('expected integer after %r, got %r' %
('-' + self.name, arg),
span_id=arg_r.SpanId())
elif case(flag_type_e.Float):
try:
val = value.Float(float(arg))
except ValueError:
e_usage('expected number after %r, got %r' %
('-' + self.name, arg),
span_id=arg_r.SpanId())
else:
raise AssertionError()
out.Set(self.name, val)
return self.quit_parsing_flags
def find_dynamic_token(part):
# type: (word_part_t) -> token|bool
"""Recursive search for dynamic token.
This is patterned on word_._EvalWordPart, but with
~inverted boolean logic: it returns the token object
if one is found, otherwise False.
"""
UP_part = part
with tagswitch(part) as case:
if case(word_part_e.ShArrayLiteral):
return cast(Token, UP_part).token
elif case(word_part_e.AssocArrayLiteral):
return cast(Token, UP_part).token
elif case(word_part_e.Literal):
return False
elif case(word_part_e.EscapedLiteral):
return False
elif case(word_part_e.SingleQuoted):
return False
elif case(word_part_e.DoubleQuoted):
part = cast(double_quoted, UP_part)
for p in part.parts:
tok = find_dynamic_token(p)
if tok:
return tok
return False
elif case(
word_part_e.CommandSub,
word_part_e.SimpleVarSub,
word_part_e.BracedVarSub,
word_part_e.TildeSub,
word_part_e.ArithSub,
word_part_e.ExtGlob,
word_part_e.Splice,
):
return cast(Token, UP_part).token
else:
raise AssertionError(part.tag_())
def _ValToIntOrError(self, val, span_id=runtime.NO_SPID):
# type: (value_t, int) -> int
try:
UP_val = val
with tagswitch(val) as case:
if case(value_e.Undef
): # 'nounset' already handled before got here
# Happens upon a[undefined]=42, which unfortunately turns into a[0]=42.
#log('blame_word %s arena %s', blame_word, self.arena)
e_die('Undefined value in arithmetic context',
span_id=span_id)
elif case(value_e.Int):
val = cast(value__Int, UP_val)
return val.i
elif case(value_e.Str):
val = cast(value__Str, UP_val)
return _StringToInteger(val.s,
span_id=span_id) # calls e_die
elif case(value_e.Obj):
# Note: this handles var x = 42; echo $(( x > 2 )).
if mylib.PYTHON:
val = cast(value__Obj, UP_val)
if isinstance(val.obj, int):
return val.obj
raise AssertionError() # not in C++
except error.FatalRuntime as e:
if self.exec_opts.strict_arith():
raise
else:
span_id = word_.SpanIdFromError(e)
self.errfmt.PrettyPrintError(e, prefix='warning: ')
return 0
# Arrays and associative arrays always fail -- not controlled by strict_arith.
# In bash, (( a )) is like (( a[0] )), but I don't want that.
# And returning '0' gives different results.
e_die("Expected a value convertible to integer, got %s",
ui.ValType(val),
span_id=span_id)
def _VarRefOrWord(self, anode):
# type: (arith_expr_t) -> Tuple[Optional[str], int]
"""
Returns (var_name, span_id) if the arith node can be interpreted that way
"""
UP_anode = anode
with tagswitch(anode) as case:
if case(arith_expr_e.VarRef):
tok = cast(Token, UP_anode)
return (tok.val, tok.span_id)
elif case(arith_expr_e.Word):
w = cast(compound_word, UP_anode)
var_name = self.EvalWordToString(w)
span_id = word_.LeftMostSpanForWord(w)
return (var_name, span_id)
no_str = None # type: str
return (no_str, runtime.NO_SPID)
def BraceExpandWords(words):
# type: (List[word_t]) -> List[compound_word]
out = [] # type: List[compound_word]
for w in words:
UP_w = w
with tagswitch(w) as case:
if case(word_e.BracedTree):
w = cast(word__BracedTree, UP_w)
parts_list = _BraceExpand(w.parts)
tmp = [compound_word(p) for p in parts_list]
out.extend(tmp)
elif case(word_e.Compound):
w = cast(compound_word, UP_w)
out.append(w)
else:
raise AssertionError(w.tag_())
return out
def _GetSplitter(self, ifs=None):
# type: (str) -> IfsSplitter
"""Based on the current stack frame, get the splitter."""
if ifs is None:
val = self.mem.GetVar('IFS')
UP_val = val
with tagswitch(val) as case:
if case(value_e.Undef):
ifs = DEFAULT_IFS
elif case(value_e.Str):
val = cast(value__Str, UP_val)
ifs = val.s
else:
# TODO: Raise proper error
raise AssertionError("IFS shouldn't be an array")
try:
sp = self.splitters[ifs]
except KeyError:
# Figure out what kind of splitter we should instantiate.
ifs_whitespace = mylib.BufWriter()
ifs_other = mylib.BufWriter()
for c in ifs:
if c in ' \t\n': # Happens to be the same as DEFAULT_IFS
ifs_whitespace.write(c)
else:
# TODO: \ not supported
ifs_other.write(c)
sp = IfsSplitter(ifs_whitespace.getvalue(), ifs_other.getvalue())
# NOTE: Technically, we could make the key more precise. IFS=$' \t' is
# the same as IFS=$'\t '. But most programs probably don't do that, and
# everything should work in any case.
self.splitters[ifs] = sp
return sp
def EvalLhs(node, arith_ev, mem, spid, lookup_mode):
# type: (sh_lhs_expr_t, ArithEvaluator, Mem, int, scope_t) -> lvalue_t
"""sh_lhs_expr -> lvalue.
Used for a=b and a[x]=b
"""
assert isinstance(node, sh_lhs_expr_t), node
UP_node = node
lval = None # type: lvalue_t
with tagswitch(node) as case:
if case(sh_lhs_expr_e.Name): # a=x
node = cast(sh_lhs_expr__Name, UP_node)
# Note: C++ constructor doesn't take spids directly. Should we add that?
lval1 = lvalue.Named(node.name)
lval1.spids.append(spid)
lval = lval1
elif case(sh_lhs_expr_e.IndexedName): # a[1+2]=x
node = cast(sh_lhs_expr__IndexedName, UP_node)
if mem.IsAssocArray(node.name, lookup_mode):
key = arith_ev.EvalWordToString(node.index)
# copy left-mode spid
lval2 = lvalue.Keyed(node.name, key)
lval2.spids.append(node.spids[0])
lval = lval2
else:
index = arith_ev.EvalToInt(node.index)
# copy left-mode spid
lval3 = lvalue.Indexed(node.name, index)
lval3.spids.append(node.spids[0])
lval = lval3
else:
raise AssertionError(node.tag_())
return lval
def SpanForLhsExpr(node):
# type: (sh_lhs_expr_t) -> int
# This switch is annoying but we don't have inheritance from the sum type
# (because of diamond issue). We might change the schema later, which maeks
# it moot. See the comment in frontend/syntax.asdl.
UP_node = node
with tagswitch(node) as case:
if case(sh_lhs_expr_e.Name):
node = cast(sh_lhs_expr__Name, UP_node)
spids = node.spids
elif case(sh_lhs_expr_e.IndexedName):
node = cast(sh_lhs_expr__IndexedName, UP_node)
spids = node.spids
else:
# Should not see UnparsedIndex
raise AssertionError()
if len(spids):
return spids[0]
else:
return runtime.NO_SPID
def RightMostSpanForWord(w):
# type: (word_t) -> int
"""Needed for here doc delimiters."""
UP_w = w
with tagswitch(w) as case:
if case(word_e.Compound):
w = cast(compound_word, UP_w)
if len(w.parts) == 0:
# TODO: Use Empty instead
raise AssertionError("Compound shouldn't be empty")
else:
end = w.parts[-1]
return _RightMostSpanForPart(end)
elif case(word_e.Empty):
return runtime.NO_SPID
elif case(word_e.Token):
tok = cast(Token, UP_w)
return tok.span_id
else:
raise AssertionError(w.tag_())
def Set(self, name, val):
# type: (str, value_t) -> None
self.attrs[name] = val
if mylib.PYTHON:
# Backward compatibility!
with tagswitch(val) as case:
if case(value_e.Undef):
py_val = None # type: Any
elif case(value_e.Bool):
py_val = cast(value__Bool, val).b
elif case(value_e.Int):
py_val = cast(value__Int, val).i
elif case(value_e.Float):
py_val = cast(value__Float, val).f
elif case(value_e.Str):
py_val = cast(value__Str, val).s
else:
raise AssertionError(val)
# debug-completion -> debug_completion
setattr(self, name.replace('-', '_'), py_val)
def EvalShellLhs(self, node, spid, lookup_mode):
# type: (sh_lhs_expr_t, int, scope_t) -> lvalue_t
"""Evaluate a shell LHS expression, i.e. place expression.
For a=b and a[x]=b etc.
"""
assert isinstance(node, sh_lhs_expr_t), node
UP_node = node
lval = None # type: lvalue_t
with tagswitch(node) as case:
if case(sh_lhs_expr_e.Name): # a=x
node = cast(sh_lhs_expr__Name, UP_node)
# Note: C++ constructor doesn't take spids directly. Should we add that?
lval1 = lvalue.Named(node.name)
lval1.spids.append(spid)
lval = lval1
elif case(sh_lhs_expr_e.IndexedName): # a[1+2]=x
node = cast(sh_lhs_expr__IndexedName, UP_node)
if self.mem.IsAssocArray(node.name, lookup_mode):
key = self.EvalWordToString(node.index)
lval2 = lvalue.Keyed(node.name, key)
lval2.spids.append(node.spids[0])
lval = lval2
else:
index = self.EvalToInt(node.index)
lval3 = lvalue.Indexed(node.name, index)
lval3.spids.append(node.spids[0])
lval = lval3
else:
raise AssertionError(node.tag_())
return lval
def OnProcessStart(self, pid, why):
# type: (int, trace_t) -> None
buf = self._RichTraceBegin('|')
if not buf:
return
# TODO: ProcessSub and PipelinePart are commonly command.Simple, and also
# Fork/ForkWait through the BraceGroup. We could print those argv arrays.
UP_why = why
with tagswitch(why) as case:
# Synchronous cases
if case(trace_e.External):
why = cast(trace__External, UP_why)
buf.write('command %d:' % pid)
_PrintArgv(why.argv, buf)
# Everything below is the same. Could use string literals?
elif case(trace_e.ForkWait):
buf.write('forkwait %d\n' % pid)
elif case(trace_e.CommandSub):
buf.write('command sub %d\n' % pid)
# Async cases
elif case(trace_e.ProcessSub):
buf.write('proc sub %d\n' % pid)
elif case(trace_e.HereDoc):
buf.write('here doc %d\n' % pid)
elif case(trace_e.Fork):
buf.write('fork %d\n' % pid)
elif case(trace_e.PipelinePart):
buf.write('part %d\n' % pid)
else:
raise AssertionError()
self.f.write(buf.getvalue())
def _ApplyRedirect(self, r, waiter):
# type: (redirect, Waiter) -> None
arg = r.arg
UP_arg = arg
with tagswitch(arg) as case:
if case(redirect_arg_e.Path):
arg = cast(redirect_arg__Path, UP_arg)
if r.op_id in (Id.Redir_Great, Id.Redir_AndGreat): # > &>
# NOTE: This is different than >| because it respects noclobber, but
# that option is almost never used. See test/wild.sh.
mode = posix.O_CREAT | posix.O_WRONLY | posix.O_TRUNC
elif r.op_id == Id.Redir_Clobber: # >|
mode = posix.O_CREAT | posix.O_WRONLY | posix.O_TRUNC
elif r.op_id in (Id.Redir_DGreat,
Id.Redir_AndDGreat): # >> &>>
mode = posix.O_CREAT | posix.O_WRONLY | posix.O_APPEND
elif r.op_id == Id.Redir_Less: # <
mode = posix.O_RDONLY
elif r.op_id == Id.Redir_LessGreat: # <>
mode = posix.O_CREAT | posix.O_RDWR
else:
raise NotImplementedError(r.op_id)
# NOTE: 0666 is affected by umask, all shells use it.
try:
open_fd = posix.open(arg.filename, mode, 0o666)
except OSError as e:
self.errfmt.Print_("Can't open %r: %s" %
(arg.filename, pyutil.strerror(e)),
span_id=r.op_spid)
raise # redirect failed
new_fd = self._PushDup(open_fd, r.loc)
if new_fd != NO_FD:
posix.close(open_fd)
# Now handle &> and &>> and their variants. These pairs are the same:
#
# stdout_stderr.py &> out-err.txt
# stdout_stderr.py > out-err.txt 2>&1
#
# stdout_stderr.py 3&> out-err.txt
# stdout_stderr.py 3> out-err.txt 2>&3
#
# Ditto for {fd}> and {fd}&>
if r.op_id in (Id.Redir_AndGreat, Id.Redir_AndDGreat):
self._PushDup(new_fd, redir_loc.Fd(2))
elif case(redirect_arg_e.CopyFd): # e.g. echo hi 1>&2
arg = cast(redirect_arg__CopyFd, UP_arg)
if r.op_id == Id.Redir_GreatAnd: # 1>&2
self._PushDup(arg.target_fd, r.loc)
elif r.op_id == Id.Redir_LessAnd: # 0<&5
# The only difference between >& and <& is the default file
# descriptor argument.
self._PushDup(arg.target_fd, r.loc)
else:
raise NotImplementedError()
elif case(redirect_arg_e.MoveFd): # e.g. echo hi 5>&6-
arg = cast(redirect_arg__MoveFd, UP_arg)
new_fd = self._PushDup(arg.target_fd, r.loc)
if new_fd != NO_FD:
posix.close(arg.target_fd)
UP_loc = r.loc
if r.loc.tag_() == redir_loc_e.Fd:
fd = cast(redir_loc__Fd, UP_loc).fd
else:
fd = NO_FD
self.cur_frame.saved.append(_RedirFrame(new_fd, fd, False))
elif case(redirect_arg_e.CloseFd): # e.g. echo hi 5>&-
self._PushCloseFd(r.loc)
elif case(redirect_arg_e.HereDoc):
arg = cast(redirect_arg__HereDoc, UP_arg)
# NOTE: Do these descriptors have to be moved out of the range 0-9?
read_fd, write_fd = posix.pipe()
self._PushDup(read_fd, r.loc) # stdin is now the pipe
# We can't close like we do in the filename case above? The writer can
# get a "broken pipe".
self._PushClose(read_fd)
thunk = _HereDocWriterThunk(write_fd, arg.body)
# TODO: Use PIPE_SIZE to save a process in the case of small here docs,
# which are the common case. (dash does this.)
start_process = True
#start_process = False
if start_process:
here_proc = Process(thunk, self.job_state)
# NOTE: we could close the read pipe here, but it doesn't really
# matter because we control the code.
_ = here_proc.Start()
#log('Started %s as %d', here_proc, pid)
self._PushWait(here_proc, waiter)
# Now that we've started the child, close it in the parent.
posix.close(write_fd)
else:
posix.write(write_fd, arg.body)
posix.close(write_fd)
def Run(self, cmd_val):
arg_r = args.Reader(cmd_val.argv, spids=cmd_val.arg_spids)
arg_r.Next() # skip 'json'
action, action_spid = arg_r.Peek2()
if action is None:
raise error.Usage(_JSON_ACTION_ERROR)
arg_r.Next()
if action == 'write':
arg, _ = JSON_WRITE_SPEC.Parse(arg_r)
# GetVar() of each name and print it.
for var_name in arg_r.Rest():
if var_name.startswith(':'):
var_name = var_name[1:]
val = self.mem.GetVar(var_name)
with tagswitch(val) as case:
if case(value_e.Undef):
# TODO: blame the right span_id
self.errfmt.Print("no variable named %r is defined",
var_name)
return 1
elif case(value_e.Str):
obj = val.s
elif case(value_e.MaybeStrArray):
obj = val.strs
elif case(value_e.AssocArray):
obj = val.d
elif case(value_e.Obj):
obj = val.obj
else:
raise AssertionError(val)
if arg.pretty:
indent = arg.indent
extra_newline = False
else:
# How yajl works: if indent is -1, then everything is on one line.
indent = -1
extra_newline = True
j = yajl.dump(obj, sys.stdout, indent=indent)
if extra_newline:
sys.stdout.write('\n')
# TODO: Accept a block. They aren't hooked up yet.
if cmd_val.block:
# TODO: flatten value.{Str,Obj} into a flat dict?
namespace = self.cmd_ev.EvalBlock(cmd_val.block)
print(yajl.dump(namespace))
elif action == 'read':
arg, _ = JSON_READ_SPEC.Parse(arg_r)
# TODO:
# Respect -validate=F
var_name, name_spid = arg_r.ReadRequired2("expected variable name")
if var_name.startswith(':'):
var_name = var_name[1:]
if not match.IsValidVarName(var_name):
raise error.Usage('got invalid variable name %r' % var_name,
span_id=name_spid)
try:
# Use a global _STDIN, because we get EBADF on a redirect if we use a
# local. A Py_DECREF closes the file, which we don't want, because the
# redirect is responsible for freeing it.
#
# https://github.com/oilshell/oil/issues/675
#
# TODO: write a better binding like yajl.readfd()
#
# It should use streaming like here:
# https://lloyd.github.io/yajl/
obj = yajl.load(_STDIN)
except ValueError as e:
self.errfmt.Print('json read: %s', e, span_id=action_spid)
return 1
self.mem.SetVar(sh_lhs_expr.Name(var_name), value.Obj(obj),
scope_e.LocalOnly)
else:
raise error.Usage(_JSON_ACTION_ERROR, span_id=action_spid)
return 0
