Lunatic translator: nearing syntax completion while treading in murky waters.

- bump lpeg stack limit to 1024 (hack) for long if/if/if...else chains
- lexical: newline, EOF and whitespace; "bad" identifiers; hex literals,
           newline terminated strings (allow empty string)
- syntax: allow nesting of array expressions, it's easier than special-casing;
          handle issues with structs expecting parm2 (hackish); userdef;
          switch/case/default
- fix parsing some commands; mind prefixes!
- frontend: if failing match, print last keyword and its position; warn on
  "bad" identifiers (one per such); batch processing from command line
- Files that locate finds from my linux box now pass (except where there are
  really syntax errors).

git-svn-id: https://svn.eduke32.com/eduke32@2616 1a8010ca-5511-0410-912e-c29ae57300e0
This commit is contained in:
helixhorned 2012-04-29 20:54:06 +00:00
parent b2b8ab7890
commit f5ee6ca7eb
1 changed files with 188 additions and 94 deletions

View File

@ -3,6 +3,17 @@
local lpeg = require("lpeg")
-- If/else nesting is problematic in CON: because a dangling 'else' is attached
-- to the outermost 'if', I think there's no way of linearizing its (recursive)
-- pattern, so the "too many pending calls/choices" is unavoidable in general.
-- This limit is of course still arbitrary, but writing if/else cascades
-- in CON isn't pretty either (though sometimes necessary because nested switches
-- don't work?)
-- See also: http://lua-users.org/lists/lua-l/2010-03/msg00086.html
lpeg.setmaxstack(1024);
local Pat, Set, Range, Var = lpeg.P, lpeg.S, lpeg.R, lpeg.V
@ -19,20 +30,24 @@ end
----==== patterns ====----
---- basic ones
local newline = Pat("\n") -- need to do stuff on newline later...
-- Windows, *nix and Mac newlines all exist in the wild!
local newline = "\r"*Pat("\n")^-1 + "\n"
local EOF = Pat(-1)
local anychar = Pat(1)
-- comments
local comment = "/*" * match_until(anychar, "*/") * "*/"
local linecomment = "//" * match_until(anychar, newline)
local whitespace = Var("whitespace")
local sp0 = whitespace^0
local sp1 = whitespace^1 -- + (-1) -- matches EOF, too
-- This "WS+" pattern matches EOF too, so that a forgotten newline at EOF is
-- properly handled
local sp1 = whitespace^1 + EOF
local alpha = Range("AZ", "az") -- locale?
local alphanum = alpha + Range("09")
local alnumtok = alphanum + Set("{}/\\*-_.") -- see isaltok() in gamedef.c
--local alnumtok = alphanum + Set("{}/\\*-_.") -- see isaltok() in gamedef.c
--- basic lexical elements ("tokens")
local t_number = Range("09")^1 + (Pat("0x") + "0X")*Range("09", "af")^1
local t_number = Range("09")^1 + (Pat("0x") + "0X")*Range("09", "af", "AF")^1
-- Valid identifier names are disjunct from keywords!
-- XXX: CON is more permissive with identifier name characters:
local t_identifier = Var("t_identifier")
@ -53,7 +68,8 @@ local t_wvar = t_arrayexp + t_identifier
---- helper patterns / pattern constructing functions
local maybe_quoted_filename = ('"' * t_filename * '"' + t_filename)
local newline_term_string = (whitespace-newline)^1 * t_newline_term_str -- XXX: empty string?
-- empty string is handled too; we must not eat the newline then!
local newline_term_string = (#newline + EOF) + (whitespace-newline)^1 * t_newline_term_str
-- (sp1 * t_define) repeated exactly n times
@ -102,6 +118,7 @@ end
-- The command names will be attached to the front of the patterns later!
--== Top level CON commands ==--
-- XXX: many of these are also allowed inside actors/states/events in CON.
local Co = {
--- 1. Preprocessor
include = sp1 * maybe_quoted_filename,
@ -163,14 +180,22 @@ local Co = {
local varop = cmd(W,D)
local varvarop = cmd(W,R)
-- t_define is t_rvar without t_arrayexp, actually, so that no nesting is allowed:
local arraypat = sp0 * "[" * sp0 * t_define * sp0 * "]"
-- Allow nesting... stuff like
-- ifvarl actorvar[sprite[THISACTOR].owner].burning 0
-- is kinda breaking the classic "no array nesting" rules
-- (if there ever were any) and making our life harder else.
local arraypat = sp0 * "[" * sp0 * t_rvar * sp0 * "]"
-- Have to bite the bullet here and list actor/player members with second parameters,
-- even though it's ugly to make it part of the syntax. Also, stuff like
-- actor[xxx].loogiex parm2 x
-- will be wrongly accepted at the parsing stage because we don't discriminate between
-- actor and player (but it will be rejected later).
local parm2memberpat = (Pat("htg_t") + "loogiex" + "loogiey" + "ammo_amount" +
"weaprecs" + "gotweapon" + "pals" + "max_ammo_amount") * sp0 * t_rvar
-- The member name must match keywords, too (_all), because e.g. cstat is a member
-- of sprite[]
-- XXX: actor and sprite members can have parm2, e.g. this is legal:
-- ifvare player[THISACTOR].gotweapon 4 0
-- but not parsed currently.
local memberpat = sp0 * "." * sp0 * t_identifier_all
-- of sprite[].
local memberpat = sp0 * "." * sp0 * (parm2memberpat + t_identifier_all)
local getstructcmd = -- get<structname>[<idx>].<member> (<parm2>)? <<var>>
-- existence of a second parameter is determined later
@ -204,7 +229,11 @@ local Ci = {
getsector = getstructcmd,
getthisprojectile = getstructcmd,
gettspr = getstructcmd,
getuserdef = getstructcmd,
-- NOTE: {get,set}userdef is the only struct that can be accessed without
-- an "array part", e.g. H266mod has "setuserdef .weaponswitch 0" (space
-- between keyword and "." is mandatory)
getuserdef = (arraypat + sp1) * memberpat * sp1 * (t_rvar * sp1 * t_wvar + t_wvar),
-- getuserdef = getstructcmd,
getwall = getstructcmd,
getactorvar = getperxvarcmd,
@ -217,7 +246,8 @@ local Ci = {
setsector = setstructcmd,
setthisprojectile = setstructcmd,
settspr = setstructcmd,
setuserdef = setstructcmd,
setuserdef = (arraypat + sp1) * memberpat * sp1 * (t_rvar * sp1 * t_wvar + t_rvar),
-- setuserdef = setstructcmd,
setwall = setstructcmd,
setactorvar = setperxvarcmd,
@ -355,7 +385,6 @@ local Ci = {
killit = cmd(),
mikesnd = cmd(),
nullop = cmd(),
operate = cmd(),
pkick = cmd(),
pstomp = cmd(),
resetactioncount = cmd(),
@ -392,12 +421,12 @@ local Ci = {
qsubstr = cmd(R,R),
-- array stuff
copy = sp1 * t_identifier * arraypat * sp1 * t_identifier * arraypat,
copy = sp1 * t_identifier * arraypat * sp1 * t_identifier * arraypat * sp1 * t_rvar,
setarray = sp1 * t_identifier * arraypat * sp1 * t_rvar,
activatebysector = cmd(R,R),
addlog = cmd(),
addlogvar = cmd(R),
addlogvar = cmd(R), -- HERE, it's significant that addlogvar
-- addlog = cmd(), -- comes before addlog!
addweaponvar = cmd(R,R), -- exec SPECIAL HANDLING!
cansee = cmd(R,R,R,R,R,R,R,R,W),
canseespr = cmd(R,R,W),
@ -416,7 +445,7 @@ local Ci = {
gametext = cmd(R,R,R,R,R,R,R,R,R,R,R), -- 11 R
gametextz = cmd(R,R,R,R,R,R,R,R,R,R,R,R), -- 12 R
digitalnumber = cmd(R,R,R,R,R,R,R,R,R,R,R), -- 11R
digitalnumberz = cmd(W,R,R,R,R,R,R,R,R,R,R,R), -- 1W 11R
digitalnumberz = cmd(R,R,R,R,R,R,R,R,R,R,R,R), -- 12R
minitext = cmd(R,R,R,R,R),
ldist = cmd(W,R,R),
@ -426,14 +455,17 @@ local Ci = {
savemapstate = cmd(),
movesprite = cmd(R,R,R,R,R,W),
neartag = cmd(R,R,R,R,R,W,W,W,W,R,R),
operateactivators = cmd(R),
operatesectors = cmd(R),
operateactivators = cmd(R,R),
operatesectors = cmd(R,R),
palfrom = (sp1 * t_define)^-4,
-- must come after all other operate* commands
-- operate = cmd(),
myos = cmd(R,R,R,R,R),
myosx = cmd(R,R,R,R,R),
myospal = cmd(R,R,R,R,R,R),
myospalx = cmd(R,R,R,R,R,R),
myosx = cmd(R,R,R,R,R),
headspritesect = cmd(R,R),
headspritestat = cmd(R,R),
@ -519,31 +551,6 @@ local Cif = {
ifsound = cmd(D),
ifpinventory = cmd(D,D),
ifp = (sp1 * t_define)^1,
ifclient = cmd(),
ifserver = cmd(),
ifonwater = cmd(),
ifinwater = cmd(),
ifactornotstayput = cmd(),
ifactorsound = cmd(),
ifcansee = cmd(),
ifhitweapon = cmd(),
ifsquished = cmd(),
ifdead = cmd(),
ifcanshoottarget = cmd(),
ifhitspace = cmd(),
ifoutside = cmd(),
ifmultiplayer = cmd(),
ifinspace = cmd(),
ifbulletnear = cmd(),
ifrespawn = cmd(),
ifinouterspace = cmd(),
ifnotmoving = cmd(),
ifawayfromwall = cmd(),
ifcanseetarget = cmd(),
ifnosounds = cmd(),
ifvarl = cmd(R,D),
ifvarg = cmd(R,D),
ifvare = cmd(R,D),
@ -553,7 +560,6 @@ local Cif = {
ifvarxor = cmd(R,D),
ifvareither = cmd(R,D),
ifactorsound = cmd(R,R),
ifvarvarg = cmd(R,R),
ifvarvarl = cmd(R,R),
ifvarvare = cmd(R,R),
@ -562,6 +568,31 @@ local Cif = {
ifvarvaror = cmd(R,R),
ifvarvarxor = cmd(R,R),
ifvarvareither = cmd(R,R),
ifactorsound = cmd(R,R),
ifp = (sp1 * t_define)^1,
ifsquished = cmd(),
ifserver = cmd(),
ifrespawn = cmd(),
ifoutside = cmd(),
ifonwater = cmd(),
ifnotmoving = cmd(),
ifnosounds = cmd(),
ifmultiplayer = cmd(),
ifinwater = cmd(),
ifinspace = cmd(),
ifinouterspace = cmd(),
ifhitweapon = cmd(),
ifhitspace = cmd(),
ifdead = cmd(),
ifclient = cmd(),
ifcanshoottarget = cmd(),
ifcanseetarget = cmd(),
-- ifcansee = cmd(),
ifbulletnear = cmd(),
ifawayfromwall = cmd(),
ifactornotstayput = cmd(),
}
@ -613,10 +644,15 @@ end
local function getlinecol(pos)
local line = bsearch(newlineidxs, pos)
local col = pos-newlineidxs[line]
local col = pos-newlineidxs[line-1]
return line, col
end
-- Last keyword position, for error diagnosis.
local g_lastkwpos = nil
local g_lastkw = nil
local g_badids = {} -- maps bad id strings to 'true'
-- A generic trace function, prints a position together with the match content
-- A non-existing 'doit' means 'true'.
local function TraceFunc(pat, label, doit)
@ -625,20 +661,42 @@ local function TraceFunc(pat, label, doit)
if (doit==nil or doit) then
local function tfunc(subj, pos, a)
local line, col = getlinecol(pos)
printf("%d,%d:%s:%s", line, col, label, a)
printf("%d,%d:%s: %s", line, col, label, a)
return true
end
pat = lpeg.Cmt(pat, tfunc)
elseif (label=="kw") then -- HACK
local function tfunc(subj, pos, a)
g_lastkwpos = pos
g_lastkw = a
return true
end
-- XXX: is there a better way?
pat = lpeg.Cmt(pat, tfunc)
end
return pat
end
local function BadIdentFunc(pat)
local function tfunc(subj, pos, a)
if (not g_badids[a]) then
local line, col = getlinecol(pos)
printf("%d,%d: warning: bad identifier: %s", line, col, a)
g_badids[a] = true
end
return true
end
return lpeg.Cmt(Pat(pat), tfunc)
end
-- These are tracers for specific patterns which can be disabled
-- if desired.
local function Keyw(kwname) return TraceFunc(kwname, "kw", true) end
local function NotKeyw(text) return TraceFunc(text, "!kw", true) end
local function Ident(idname) return TraceFunc(idname, "id", true) end
local function Stmt(cmdpat) return TraceFunc(cmdpat, "st", true) end
local function Keyw(kwname) return TraceFunc(kwname, "kw", false) end
local function NotKeyw(text) return TraceFunc(text, "!kw", false) end
local function Ident(idname) return TraceFunc(idname, "id", false) end
local function BadIdent(idname) return BadIdentFunc(idname) end
local function Stmt(cmdpat) return TraceFunc(cmdpat, "st", false) end
----==== Translator continued ====----
@ -662,8 +720,10 @@ local function all_alt_pattern(...)
local args = {...}
for argi=1,#args do
local pattab = args[argi]
-- NOTE: pairs() iterates in undefined order!
-- We can't handle prefix-problematic commands this way here.
for cmdname,cmdpat in pairs(pattab) do
pat = pat + cmdpat
pat = cmdpat + pat
end
end
return pat
@ -671,24 +731,32 @@ end
-- actor ORGANTIC is greeting!
local function warn_on_lonely_else(subj, pos)
print(pos..": warning: found `else' with no `if'")
local line, col = getlinecol(pos)
printf("%d,%d: warning: found `else' with no `if'", line, col)
return true
end
-- About prefixes: I think it's not a problem *here* if e.g. "getactor" comes
-- before "getactorvar", because the pattern for the former will fail
-- eventually in the ordered choice if fed with the latter. However, it DOES
-- matter in the keyword list, see NotKeyw() trace function and comment in
-- con_lang.lua.
-- NOTE: The indented text is not true, e.g. addlog vs. addlogvar:
-- since 'addlog' has no args, it will get matched given an 'addlogvar' in the subject:
-- About prefixes: I think it's not a problem *here* if e.g. "getactor" comes
-- before "getactorvar", because the pattern for the former will fail
-- eventually in the ordered choice if fed with the latter. However, it DOES
-- matter in the keyword list, see NotKeyw() trace function and comment in
-- con_lang.lua.
-- Do we have more of them? Yes.
-- operate/operate*
-- ifcansee/ifcanseetarget
local con_outer_command = all_alt_pattern(Co)
local con_inner_command = all_alt_pattern(Ci)
local con_if_begs = all_alt_pattern(Cif)
-- Empty-arged commands that are prefixes of others must come last:
local con_inner_command = all_alt_pattern(Ci) + "addlog" + "operate"
local con_if_begs = all_alt_pattern(Cif) + "ifcansee"
local lone_else = lpeg.Cmt("else" * sp1, warn_on_lonely_else)
local stmt_list = Var("stmt_list")
-- possibly empty statement list:
local stmt_list_or_eps = (stmt_list * sp1)^-1
local stmt_list_nosp_or_eps = (stmt_list * (sp1 * stmt_list)^0)^-1
-- common to all three: <name/tilenum> [<strength> [<action> [<move> [<ai>... ]]]]
local common_actor_end = sp1 * t_define * sp1 * (t_define * sp1)^0 * stmt_list_or_eps * "enda"
@ -710,19 +778,32 @@ local Cb = {
attachnames(Cb)
local t_good_identifier = Range("AZ", "az", "__") * Range("AZ", "az", "__", "09")^0
-- CON isaltok also has chars in "{}.", but these could potentially
-- interfere with *CON* syntax. The "]" is so that the number in array[80]
-- isn't considered a broken identifier.
-- "-" is somewhat problematic, but we allow it only as 2nd and up character, so
-- there's no ambiguity with unary minus. (Commands must be separated by spaces
-- in CON, so a trailing "-" is "OK", too.)
-- This is broken in itself, so we ought to make a compatibility/modern CON switch.
local t_broken_identifier = BadIdent(-((t_number + t_good_identifier) * (sp1 + Set("[]:"))) *
(alphanum + Set("_/\\*")) * (alphanum + Set("_/\\*-"))^0)
--- The final grammar!
local Grammar = Pat{
-- The starting symbol.
-- A translation unit is a (possibly empty) sequence of outer CON
-- commands, separated by at least one whitespace which may be
-- omitted at the EOF.
sp0 * ((con_outer_command + all_alt_pattern(Cb)) * (sp1 + (-1)))^0,
sp0 * ((con_outer_command + all_alt_pattern(Cb)) * sp1)^0,
-- Deps. These appear here because we're hitting a limit with LPeg else:
-- http://lua-users.org/lists/lua-l/2008-11/msg00462.html
whitespace = Set(" \t\r") + newline + Set("(),;") + comment + linecomment,
-- NOTE: NW demo (NWSNOW.CON) contains a Ctrl-Z char (dec 26)
whitespace = Set(" \t\r\26") + newline + Set("(),;") + comment + linecomment,
t_identifier_all = Range("AZ", "az", "__") * Range("AZ", "az", "__", "09")^0,
t_identifier_all = t_broken_identifier + t_good_identifier,
-- NOTE: -con_keyword alone would be wrong, e.g. "state breakobject":
-- NOTE 2: The + "[" is so that stuff like
-- getactor[THISACTOR].x x
@ -732,13 +813,19 @@ local Grammar = Pat{
-- getactor [THISACTOR].y y
-- This is in need of cleanup!
t_identifier = -NotKeyw(con_keyword * (sp1 + "[")) * Ident(t_identifier_all),
t_define = Pat("-")^-1 * sp0 * (t_identifier + t_number),
t_define = (Pat("-") * sp0)^-1 * (t_identifier + t_number),
t_arrayexp = t_identifier * arraypat * memberpat^-1,
switch_stmt = Keyw("switch") * (sp1 * (Var("case") + Var("default")))^0 * sp1 * "endswitch",
case = Keyw("case") * sp1 * t_define * sp0 * Pat(":")^-1 * sp1 * stmt_list_or_eps * "break",
default = Keyw("default") * sp0 * Pat(":")^-1 * sp1 * stmt_list_or_eps * "break",
-- SWITCH
switch_stmt = Keyw("switch") * sp1 * t_rvar *
(Var("case_block") + Var("default_block"))^0 * sp1 * "endswitch",
-- NOTE: some old DNWMD has "case: PIGCOP". I don't think I'll allow that.
case_block = (sp1 * Keyw("case") * sp1 * t_define * (sp0*":")^-1)^1 * sp1 *
stmt_list_nosp_or_eps, -- * "break",
default_block = sp1 * Keyw("default") * (sp0*":"*sp0 + sp1) * stmt_list_nosp_or_eps, -- * "break",
-- The "lone" if statement is tested first, so that a potential dangling "else" is
-- attached to the outermost possible "if", as done by CON
@ -751,7 +838,7 @@ local Grammar = Pat{
-- TODO: some sp1 --> sp0?
single_stmt = Stmt(
lone_else^-1 *
( Keyw("{") * sp0 * "}"
( Keyw("{") * sp1 * "}" -- space separation of commands in CON is for a reason!
+ Keyw("{") * sp1 * stmt_list * sp1 * "}"
+ (con_inner_command + Var("switch_stmt") + Var("if_stmt") + Var("while_stmt"))
-- + lpeg.Cmt(t_newline_term_str, function (subj, curpos) print("Error at "..curpos) end)
@ -769,37 +856,44 @@ local function setup_newlineidxs(contents)
for i in string.gmatch(contents, "()\n") do
newlineidxs[#newlineidxs+1] = i
end
newlineidxs[#newlineidxs+1] = #contents+1 -- dummy newline
-- dummy newlines at beginning and end
newlineidxs[#newlineidxs+1] = #contents+1
newlineidxs[0] = 0
end
---=== stand-alone: ===---
if (not EDUKE32_LUNATIC) then
local io = require("io")
local filename = arg[1]
assert(filename)
for argi=1,#arg do
local filename = arg[argi]
printf("\n---- Parsing file \"%s\"", filename);
local contents = io.open(filename):read("*all")
setup_newlineidxs(contents)
local contents = io.open(filename):read("*all")
setup_newlineidxs(contents)
local idx = lpeg.match(Grammar, contents)
g_badids = {}
if (not idx) then
print("Match failed.")
return
local idx = lpeg.match(Grammar, contents)
if (not idx) then
print("Match failed.")
elseif (idx == #contents+1) then
print("Matched whole contents.")
else
local i, col = getlinecol(idx)
local bi, ei = newlineidxs[i]+1, newlineidxs[i+1]-1
printf("Match succeeded up to %d (line %d, col %d; len=%d)",
idx, i, col, #contents)
-- printf("Line goes from %d to %d", bi, ei)
print(string.sub(contents, bi, ei))
if (g_lastkwpos) then
i, col = getlinecol(g_lastkwpos)
printf("Last keyword was at line %d, col %d: %s", i, col, g_lastkw)
end
end
end
if (idx == #contents+1) then
print("Matched whole contents.")
return
end
local i, col = getlinecol(idx)
local bi, ei = newlineidxs[i]+1, newlineidxs[i+1]-1
printf("Match succeeded up to %d (line %d, col %d; len=%d)",
idx, i, col, #contents)
-- printf("Line goes from %d to %d", bi, ei)
print(string.sub(contents, bi, ei))
end