def _get_pre_context_epilog_definition(dial_db):
backup_position = Lng.REGISTER_NAME(E_R.BackupStreamPositionOfLexemeStartP)
txt = [
Lng.LABEL(DoorID.global_end_of_pre_context_check(dial_db)),
#-------------------
Lng.IF(backup_position, "!=", "((QUEX_TYPE_STREAM_POSITION)-1)"),
# "QUEX_NAME(Buffer_print_content)(&me->buffer);\n",
# "std::cout << std::endl;\n",
Lng.IF("false", "==", Lng.BUFFER_SEEK(backup_position)),
Lng.RAISE_ERROR_FLAG("E_Error_File_SeekFailed"),
Lng.RETURN,
Lng.END_IF,
Lng.LEXEME_START_SET(PositionStorage=None), # use '_read_p'
# "std::cout << \"lexst \" << me->buffer._lexeme_start_p[0] << std::endl;",
# "std::cout << \"readp \" << me->buffer._read_p[0] << std::endl;",
# "QUEX_NAME(Buffer_print_content)(&me->buffer);\n",
# "std::cout << std::endl;\n",
Lng.ASSIGN(backup_position, "((QUEX_TYPE_STREAM_POSITION)-1)"),
Lng.ELSE_FOLLOWS,
#-----------------------
# -- set the input stream back to the real current position.
# during backward lexing the analyzer went backwards, so it needs to be reset.
Lng.INPUT_P_TO_LEXEME_START(),
Lng.END_IF,
]
return [ "%s\n" % line for line in txt ]
def framework(txt, PWState, TheAnalyzer):
"""Implement the Pathwalker's framework. The scheme for a path-walker
is the following:
Pathwalker Head:
Compares the current 'input' character if it is still
on the path or not. If it is on the path we increment
the 'path_iterator' and re-enter the path walker. If
not, then the thread of control enters the transition
map.
Pathwalker Transition Map:
The transition map is the common transition map that all
implemented states had in common. Now, transitions to
states outside the path may happen.
"""
dial_db = PWState.entry.dial_db
# Three Versions of PathWalker Heads:
if PWState.uniform_door_id is not None:
# UNIFORM PATHS: Along the path, always the same (or no) commands are executed.
#
# PathWalker Head Implementation:
#
# if input == *path_iterator:
# path_iterator += 1
# if *path_iterator != TerminationCode: goto CommonPathWalkerDoor
# else: goto TerminalDoor
#
# -- "goto CommonPathWalkerDoor"
goto_next_door = " %s\n" % Lng.GOTO(PWState.uniform_door_id,
dial_db)
# -- "goto TerminalDoor"
if PWState.uniform_terminal_door_id is not None:
# All path have same terminal state and enter it at the same door
goto_terminal_door = " %s\n" % Lng.GOTO(
PWState.uniform_terminal_door_id, dial_db)
else:
# The terminals of the paths are different
#
# The "goto TerminalDoor" is implemented for each path. The single
# goto is split into a sequence:
#
# if path_iterator == path_0_end: goto TerminalDoorOfPath0
# else if path_iterator == path_1_end: goto TerminalDoorOfPath1
# else if path_iterator == path_2_end: goto TerminalDoorOfPath2
# ...
tmp = ""
offset = 0
for path_id, door_id_sequence in enumerate(
PWState.door_id_sequence_list):
offset += len(door_id_sequence) + 1
tmp += " %s" % Lng.IF("path_iterator", "==", "&path_walker_%i_path_base[%s]" % \
(PWState.index, offset - 1), FirstF=(path_id == 0)) \
+ " %s\n" % Lng.GOTO(door_id_sequence[-1], dial_db)
tmp += " %s" % Lng.ELSE_FOLLOWS
tmp += " %s\n" % Lng.UNREACHABLE
tmp += " %s\n" % Lng.END_IF
goto_terminal_door = tmp
path_walker_head = \
[" %s" % Lng.IF_INPUT("==", "*path_iterator"),
" %s\n" % Lng.PATH_ITERATOR_INCREMENT,
" %s" % Lng.IF("*path_iterator", "!=", "QUEX_SETTING_BUFFER_LEXATOM_PATH_TERMINATION"),
goto_next_door,
" %s\n" % Lng.ELSE_FOLLOWS,
goto_terminal_door,
" %s\n" % Lng.END_IF,
" %s\n" % Lng.END_IF]
else:
# NON UNIFORM PATHS
#
# PathWalker Head Implementation:
#
# if input == *path_iterator:
# path_iterator += 1
# goto NextDoor(path_iterator)
#
# Here, the "goto TerminalDoor" results from NextDoor(path_iterator)
# automatically, when the path_iterator stands on the last element.
#
label = "path_walker_%i_state_base[path_iterator - path_walker_%i_reference]" \
% (PWState.index, PWState.index)
goto_next_door = "%s" % (Lng.GOTO_BY_VARIABLE(label))
path_walker_head = [
" %s" % Lng.IF_INPUT("==", "*path_iterator"),
" %s\n" % Lng.PATH_ITERATOR_INCREMENT,
" %s\n" % goto_next_door,
" %s\n" % Lng.END_IF
]
txt.extend(path_walker_head)
return
def __frame(FunctionName, CodeTxt, IteratorName, DoorIdReturn, dial_db):
txt = [ \
"static void\n" \
+ "%s(QUEX_TYPE_ANALYZER* me, QUEX_TYPE_LEXATOM* LexemeBegin, QUEX_TYPE_LEXATOM* LexemeEnd)\n" % FunctionName \
+ "{\n" \
]
if IteratorName:
state_router_adr = DoorID.global_state_router(dial_db).related_address
state_router_label = Lng.LABEL_STR_BY_ADR(state_router_adr)
txt.extend([
"# define self (*me)\n",
"/* 'QUEX_GOTO_STATE' requires 'QUEX_LABEL_STATE_ROUTER' */\n",
"# define QUEX_LABEL_STATE_ROUTER %s\n" % state_router_label
])
# Following function refers to the global 'variable_db'
txt.append(Lng.VARIABLE_DEFINITIONS(variable_db))
txt.extend([
" (void)me;\n",
Lng.COUNTER_SHIFT_VALUES(),
"%s" % Lng.ML_COMMENT("Allow LexemeBegin == LexemeEnd (e.g. END_OF_STREAM)\n"
"=> Caller does not need to check\n"
"BUT, if so quit immediately after 'shift values'."),
" __quex_assert(LexemeBegin <= LexemeEnd);\n",
" %s" % Lng.IF("LexemeBegin", "==", "LexemeEnd"),
" %s\n" % Lng.PURE_RETURN,
" %s\n" % Lng.END_IF,
" %s = LexemeBegin;\n" % IteratorName
])
txt.extend(CodeTxt)
if IteratorName:
door_id_failure = DoorID.incidence(E_IncidenceIDs.MATCH_FAILURE, dial_db)
door_id_bad_lexatom = DoorID.incidence(E_IncidenceIDs.BAD_LEXATOM, dial_db)
txt.append(
"%s /* TERMINAL: BAD_LEXATOM */\n;\n" % Lng.LABEL(door_id_bad_lexatom)
# BETTER: A lexeme that is 'counted' has already matched!
# => FAILURE is impossible!
# "%s /* TERMINAL: FAILURE */\n%s\n" % Lng.UNREACHABLE
+ "%s /* TERMINAL: FAILURE */\n%s\n" % (Lng.LABEL(door_id_failure),
Lng.GOTO(DoorIdReturn, dial_db))
)
txt.append(
"%s\n" % Lng.LABEL(DoorIdReturn)
+ "%s\n" % Lng.COMMENT("Assert: lexeme in codec's character boundaries.") \
+ " __quex_assert(%s == LexemeEnd);\n" % IteratorName \
+ " return;\n" \
+ "".join(generator.do_state_router(dial_db)) \
+ "%s\n" % Lng.UNDEFINE("self")
+ "%s\n" % Lng.UNDEFINE("QUEX_LABEL_STATE_ROUTER")
# If there is no MATCH_FAILURE, then DoorIdBeyond is still referenced as 'gotoed',
# but MATCH_FAILURE is never implemented, later on, because its DoorId is not
# referenced.
+ "$$<not-computed-gotos>----------------------------------------------\n"
+ " %s /* in QUEX_GOTO_STATE */\n" % Lng.GOTO(DoorID.global_state_router(dial_db), dial_db)
+ " %s /* to BAD_LEXATOM */\n" % Lng.GOTO(DoorID.incidence(E_IncidenceIDs.BAD_LEXATOM, dial_db), dial_db)
+ "$$------------------------------------------------------------------\n"
+ " %s\n" % Lng.COMMENT("Avoid compiler warning: 'Unused labels'") \
+ " %s\n" % Lng.GOTO(door_id_failure, dial_db) \
+ " (void)target_state_index;\n"
+ " (void)target_state_else_index;\n"
)
txt.append("}\n")
return "".join(Lng.GET_PLAIN_STRINGS(txt, dial_db))
