builtin/common/misc_helpers.lua

   1 -- Minetest: builtin/misc_helpers.lua
   2
   3 --------------------------------------------------------------------------------
   4 -- Localize functions to avoid table lookups (better performance).
   5 local table_insert = table.insert
   6 local string_sub, string_find = string.sub, string.find
   7
   8 --------------------------------------------------------------------------------
   9 function basic_dump(o)
  10         local tp = type(o)
  11         if tp == "number" then
  12                 return tostring(o)
  13         elseif tp == "string" then
  14                 return string.format("%q", o)
  15         elseif tp == "boolean" then
  16                 return tostring(o)
  17         elseif tp == "nil" then
  18                 return "nil"
  19         -- Uncomment for full function dumping support.
  20         -- Not currently enabled because bytecode isn't very human-readable and
  21         -- dump's output is intended for humans.
  22         --elseif tp == "function" then
  23         --      return string.format("loadstring(%q)", string.dump(o))
  24         else
  25                 return string.format("<%s>", tp)
  26         end
  27 end
  28
  29 local keywords = {
  30         ["and"] = true,
  31         ["break"] = true,
  32         ["do"] = true,
  33         ["else"] = true,
  34         ["elseif"] = true,
  35         ["end"] = true,
  36         ["false"] = true,
  37         ["for"] = true,
  38         ["function"] = true,
  39         ["goto"] = true,  -- Lua 5.2
  40         ["if"] = true,
  41         ["in"] = true,
  42         ["local"] = true,
  43         ["nil"] = true,
  44         ["not"] = true,
  45         ["or"] = true,
  46         ["repeat"] = true,
  47         ["return"] = true,
  48         ["then"] = true,
  49         ["true"] = true,
  50         ["until"] = true,
  51         ["while"] = true,
  52 }
  53 local function is_valid_identifier(str)
  54         if not str:find("^[a-zA-Z_][a-zA-Z0-9_]*$") or keywords[str] then
  55                 return false
  56         end
  57         return true
  58 end
  59
  60 --------------------------------------------------------------------------------
  61 -- Dumps values in a line-per-value format.
  62 -- For example, {test = {"Testing..."}} becomes:
  63 --   _["test"] = {}
  64 --   _["test"][1] = "Testing..."
  65 -- This handles tables as keys and circular references properly.
  66 -- It also handles multiple references well, writing the table only once.
  67 -- The dumped argument is internal-only.
  68
  69 function dump2(o, name, dumped)
  70         name = name or "_"
  71         -- "dumped" is used to keep track of serialized tables to handle
  72         -- multiple references and circular tables properly.
  73         -- It only contains tables as keys.  The value is the name that
  74         -- the table has in the dump, eg:
  75         -- {x = {"y"}} -> dumped[{"y"}] = '_["x"]'
  76         dumped = dumped or {}
  77         if type(o) ~= "table" then
  78                 return string.format("%s = %s\n", name, basic_dump(o))
  79         end
  80         if dumped[o] then
  81                 return string.format("%s = %s\n", name, dumped[o])
  82         end
  83         dumped[o] = name
  84         -- This contains a list of strings to be concatenated later (because
  85         -- Lua is slow at individual concatenation).
  86         local t = {}
  87         for k, v in pairs(o) do
  88                 local keyStr
  89                 if type(k) == "table" then
  90                         if dumped[k] then
  91                                 keyStr = dumped[k]
  92                         else
  93                                 -- Key tables don't have a name, so use one of
  94                                 -- the form _G["table: 0xFFFFFFF"]
  95                                 keyStr = string.format("_G[%q]", tostring(k))
  96                                 -- Dump key table
  97                                 table_insert(t, dump2(k, keyStr, dumped))
  98                         end
  99                 else
 100                         keyStr = basic_dump(k)
 101                 end
 102                 local vname = string.format("%s[%s]", name, keyStr)
 103                 table_insert(t, dump2(v, vname, dumped))
 104         end
 105         return string.format("%s = {}\n%s", name, table.concat(t))
 106 end
 107
 108 --------------------------------------------------------------------------------
 109 -- This dumps values in a one-statement format.
 110 -- For example, {test = {"Testing..."}} becomes:
 111 -- [[{
 112 --      test = {
 113 --              "Testing..."
 114 --      }
 115 -- }]]
 116 -- This supports tables as keys, but not circular references.
 117 -- It performs poorly with multiple references as it writes out the full
 118 -- table each time.
 119 -- The indent field specifies a indentation string, it defaults to a tab.
 120 -- Use the empty string to disable indentation.
 121 -- The dumped and level arguments are internal-only.
 122
 123 function dump(o, indent, nested, level)
 124         if type(o) ~= "table" then
 125                 return basic_dump(o)
 126         end
 127         -- Contains table -> true/nil of currently nested tables
 128         nested = nested or {}
 129         if nested[o] then
 130                 return "<circular reference>"
 131         end
 132         nested[o] = true
 133         indent = indent or "\t"
 134         level = level or 1
 135         local t = {}
 136         local dumped_indexes = {}
 137         for i, v in ipairs(o) do
 138                 table_insert(t, dump(v, indent, nested, level + 1))
 139                 dumped_indexes[i] = true
 140         end
 141         for k, v in pairs(o) do
 142                 if not dumped_indexes[k] then
 143                         if type(k) ~= "string" or not is_valid_identifier(k) then
 144                                 k = "["..dump(k, indent, nested, level + 1).."]"
 145                         end
 146                         v = dump(v, indent, nested, level + 1)
 147                         table_insert(t, k.." = "..v)
 148                 end
 149         end
 150         nested[o] = nil
 151         if indent ~= "" then
 152                 local indent_str = "\n"..string.rep(indent, level)
 153                 local end_indent_str = "\n"..string.rep(indent, level - 1)
 154                 return string.format("{%s%s%s}",
 155                                 indent_str,
 156                                 table.concat(t, ","..indent_str),
 157                                 end_indent_str)
 158         end
 159         return "{"..table.concat(t, ", ").."}"
 160 end
 161
 162 --------------------------------------------------------------------------------
 163 function string.split(str, delim, include_empty, max_splits, sep_is_pattern)
 164         delim = delim or ","
 165         max_splits = max_splits or -1
 166         local items = {}
 167         local pos, len, seplen = 1, #str, #delim
 168         local plain = not sep_is_pattern
 169         max_splits = max_splits + 1
 170         repeat
 171                 local np, npe = string_find(str, delim, pos, plain)
 172                 np, npe = (np or (len+1)), (npe or (len+1))
 173                 if (not np) or (max_splits == 1) then
 174                         np = len + 1
 175                         npe = np
 176                 end
 177                 local s = string_sub(str, pos, np - 1)
 178                 if include_empty or (s ~= "") then
 179                         max_splits = max_splits - 1
 180                         table_insert(items, s)
 181                 end
 182                 pos = npe + 1
 183         until (max_splits == 0) or (pos > (len + 1))
 184         return items
 185 end
 186
 187 --------------------------------------------------------------------------------
 188 function table.indexof(list, val)
 189         for i = 1, #list do
 190                 if list[i] == val then
 191                         return i
 192                 end
 193         end
 194         return -1
 195 end
 196
 197 assert(table.indexof({"foo", "bar"}, "foo") == 1)
 198 assert(table.indexof({"foo", "bar"}, "baz") == -1)
 199
 200 --------------------------------------------------------------------------------
 201 function file_exists(filename)
 202         local f = io.open(filename, "r")
 203         if f == nil then
 204                 return false
 205         else
 206                 f:close()
 207                 return true
 208         end
 209 end
 210
 211 --------------------------------------------------------------------------------
 212 function string:trim()
 213         return (self:gsub("^%s*(.-)%s*$", "%1"))
 214 end
 215
 216 assert(string.trim("\n \t\tfoo bar\t ") == "foo bar")
 217
 218 --------------------------------------------------------------------------------
 219 function math.hypot(x, y)
 220         local t
 221         x = math.abs(x)
 222         y = math.abs(y)
 223         t = math.min(x, y)
 224         x = math.max(x, y)
 225         if x == 0 then return 0 end
 226         t = t / x
 227         return x * math.sqrt(1 + t * t)
 228 end
 229
 230 --------------------------------------------------------------------------------
 231 function math.sign(x, tolerance)
 232         tolerance = tolerance or 0
 233         if x > tolerance then
 234                 return 1
 235         elseif x < -tolerance then
 236                 return -1
 237         end
 238         return 0
 239 end
 240
 241 --------------------------------------------------------------------------------
 242 function get_last_folder(text,count)
 243         local parts = text:split(DIR_DELIM)
 244
 245         if count == nil then
 246                 return parts[#parts]
 247         end
 248
 249         local retval = ""
 250         for i=1,count,1 do
 251                 retval = retval .. parts[#parts - (count-i)] .. DIR_DELIM
 252         end
 253
 254         return retval
 255 end
 256
 257 --------------------------------------------------------------------------------
 258 function cleanup_path(temppath)
 259
 260         local parts = temppath:split("-")
 261         temppath = ""
 262         for i=1,#parts,1 do
 263                 if temppath ~= "" then
 264                         temppath = temppath .. "_"
 265                 end
 266                 temppath = temppath .. parts[i]
 267         end
 268
 269         parts = temppath:split(".")
 270         temppath = ""
 271         for i=1,#parts,1 do
 272                 if temppath ~= "" then
 273                         temppath = temppath .. "_"
 274                 end
 275                 temppath = temppath .. parts[i]
 276         end
 277
 278         parts = temppath:split("'")
 279         temppath = ""
 280         for i=1,#parts,1 do
 281                 if temppath ~= "" then
 282                         temppath = temppath .. ""
 283                 end
 284                 temppath = temppath .. parts[i]
 285         end
 286
 287         parts = temppath:split(" ")
 288         temppath = ""
 289         for i=1,#parts,1 do
 290                 if temppath ~= "" then
 291                         temppath = temppath
 292                 end
 293                 temppath = temppath .. parts[i]
 294         end
 295
 296         return temppath
 297 end
 298
 299 function core.formspec_escape(text)
 300         if text ~= nil then
 301                 text = string.gsub(text,"\\","\\\\")
 302                 text = string.gsub(text,"%]","\\]")
 303                 text = string.gsub(text,"%[","\\[")
 304                 text = string.gsub(text,";","\\;")
 305                 text = string.gsub(text,",","\\,")
 306         end
 307         return text
 308 end
 309
 310
 311 function core.splittext(text,charlimit)
 312         local retval = {}
 313
 314         local current_idx = 1
 315
 316         local start,stop = string_find(text, " ", current_idx)
 317         local nl_start,nl_stop = string_find(text, "\n", current_idx)
 318         local gotnewline = false
 319         if nl_start ~= nil and (start == nil or nl_start < start) then
 320                 start = nl_start
 321                 stop = nl_stop
 322                 gotnewline = true
 323         end
 324         local last_line = ""
 325         while start ~= nil do
 326                 if string.len(last_line) + (stop-start) > charlimit then
 327                         table_insert(retval, last_line)
 328                         last_line = ""
 329                 end
 330
 331                 if last_line ~= "" then
 332                         last_line = last_line .. " "
 333                 end
 334
 335                 last_line = last_line .. string_sub(text, current_idx, stop - 1)
 336
 337                 if gotnewline then
 338                         table_insert(retval, last_line)
 339                         last_line = ""
 340                         gotnewline = false
 341                 end
 342                 current_idx = stop+1
 343
 344                 start,stop = string_find(text, " ", current_idx)
 345                 nl_start,nl_stop = string_find(text, "\n", current_idx)
 346
 347                 if nl_start ~= nil and (start == nil or nl_start < start) then
 348                         start = nl_start
 349                         stop = nl_stop
 350                         gotnewline = true
 351                 end
 352         end
 353
 354         --add last part of text
 355         if string.len(last_line) + (string.len(text) - current_idx) > charlimit then
 356                         table_insert(retval, last_line)
 357                         table_insert(retval, string_sub(text, current_idx))
 358         else
 359                 last_line = last_line .. " " .. string_sub(text, current_idx)
 360                 table_insert(retval, last_line)
 361         end
 362
 363         return retval
 364 end
 365
 366 --------------------------------------------------------------------------------
 367
 368 if INIT == "game" then
 369         local dirs1 = {9, 18, 7, 12}
 370         local dirs2 = {20, 23, 22, 21}
 371
 372         function core.rotate_and_place(itemstack, placer, pointed_thing,
 373                                 infinitestacks, orient_flags)
 374                 orient_flags = orient_flags or {}
 375
 376                 local unode = core.get_node_or_nil(pointed_thing.under)
 377                 if not unode then
 378                         return
 379                 end
 380                 local undef = core.registered_nodes[unode.name]
 381                 if undef and undef.on_rightclick then
 382                         undef.on_rightclick(pointed_thing.under, unode, placer,
 383                                         itemstack, pointed_thing)
 384                         return
 385                 end
 386                 local pitch = placer:get_look_pitch()
 387                 local fdir = core.dir_to_facedir(placer:get_look_dir())
 388                 local wield_name = itemstack:get_name()
 389
 390                 local above = pointed_thing.above
 391                 local under = pointed_thing.under
 392                 local iswall = (above.y == under.y)
 393                 local isceiling = not iswall and (above.y < under.y)
 394                 local anode = core.get_node_or_nil(above)
 395                 if not anode then
 396                         return
 397                 end
 398                 local pos = pointed_thing.above
 399                 local node = anode
 400
 401                 if undef and undef.buildable_to then
 402                         pos = pointed_thing.under
 403                         node = unode
 404                         iswall = false
 405                 end
 406
 407                 if core.is_protected(pos, placer:get_player_name()) then
 408                         core.record_protection_violation(pos,
 409                                         placer:get_player_name())
 410                         return
 411                 end
 412
 413                 local ndef = core.registered_nodes[node.name]
 414                 if not ndef or not ndef.buildable_to then
 415                         return
 416                 end
 417
 418                 if orient_flags.force_floor then
 419                         iswall = false
 420                         isceiling = false
 421                 elseif orient_flags.force_ceiling then
 422                         iswall = false
 423                         isceiling = true
 424                 elseif orient_flags.force_wall then
 425                         iswall = true
 426                         isceiling = false
 427                 elseif orient_flags.invert_wall then
 428                         iswall = not iswall
 429                 end
 430
 431                 if iswall then
 432                         core.set_node(pos, {name = wield_name,
 433                                         param2 = dirs1[fdir+1]})
 434                 elseif isceiling then
 435                         if orient_flags.force_facedir then
 436                                 core.set_node(pos, {name = wield_name,
 437                                                 param2 = 20})
 438                         else
 439                                 core.set_node(pos, {name = wield_name,
 440                                                 param2 = dirs2[fdir+1]})
 441                         end
 442                 else -- place right side up
 443                         if orient_flags.force_facedir then
 444                                 core.set_node(pos, {name = wield_name,
 445                                                 param2 = 0})
 446                         else
 447                                 core.set_node(pos, {name = wield_name,
 448                                                 param2 = fdir})
 449                         end
 450                 end
 451
 452                 if not infinitestacks then
 453                         itemstack:take_item()
 454                         return itemstack
 455                 end
 456         end
 457
 458
 459 --------------------------------------------------------------------------------
 460 --Wrapper for rotate_and_place() to check for sneak and assume Creative mode
 461 --implies infinite stacks when performing a 6d rotation.
 462 --------------------------------------------------------------------------------
 463
 464
 465         core.rotate_node = function(itemstack, placer, pointed_thing)
 466                 core.rotate_and_place(itemstack, placer, pointed_thing,
 467                                 core.setting_getbool("creative_mode"),
 468                                 {invert_wall = placer:get_player_control().sneak})
 469                 return itemstack
 470         end
 471 end
 472
 473 --------------------------------------------------------------------------------
 474 function core.explode_table_event(evt)
 475         if evt ~= nil then
 476                 local parts = evt:split(":")
 477                 if #parts == 3 then
 478                         local t = parts[1]:trim()
 479                         local r = tonumber(parts[2]:trim())
 480                         local c = tonumber(parts[3]:trim())
 481                         if type(r) == "number" and type(c) == "number"
 482                                         and t ~= "INV" then
 483                                 return {type=t, row=r, column=c}
 484                         end
 485                 end
 486         end
 487         return {type="INV", row=0, column=0}
 488 end
 489
 490 --------------------------------------------------------------------------------
 491 function core.explode_textlist_event(evt)
 492         if evt ~= nil then
 493                 local parts = evt:split(":")
 494                 if #parts == 2 then
 495                         local t = parts[1]:trim()
 496                         local r = tonumber(parts[2]:trim())
 497                         if type(r) == "number" and t ~= "INV" then
 498                                 return {type=t, index=r}
 499                         end
 500                 end
 501         end
 502         return {type="INV", index=0}
 503 end
 504
 505 --------------------------------------------------------------------------------
 506 function core.explode_scrollbar_event(evt)
 507         local retval = core.explode_textlist_event(evt)
 508
 509         retval.value = retval.index
 510         retval.index = nil
 511
 512         return retval
 513 end
 514
 515 --------------------------------------------------------------------------------
 516 function core.pos_to_string(pos, decimal_places)
 517         local x = pos.x
 518         local y = pos.y
 519         local z = pos.z
 520         if decimal_places ~= nil then
 521                 x = string.format("%." .. decimal_places .. "f", x)
 522                 y = string.format("%." .. decimal_places .. "f", y)
 523                 z = string.format("%." .. decimal_places .. "f", z)
 524         end
 525         return "(" .. x .. "," .. y .. "," .. z .. ")"
 526 end
 527
 528 --------------------------------------------------------------------------------
 529 function core.string_to_pos(value)
 530         if value == nil then
 531                 return nil
 532         end
 533
 534         local p = {}
 535         p.x, p.y, p.z = string.match(value, "^([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+)$")
 536         if p.x and p.y and p.z then
 537                 p.x = tonumber(p.x)
 538                 p.y = tonumber(p.y)
 539                 p.z = tonumber(p.z)
 540                 return p
 541         end
 542         local p = {}
 543         p.x, p.y, p.z = string.match(value, "^%( *([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+) *%)$")
 544         if p.x and p.y and p.z then
 545                 p.x = tonumber(p.x)
 546                 p.y = tonumber(p.y)
 547                 p.z = tonumber(p.z)
 548                 return p
 549         end
 550         return nil
 551 end
 552
 553 assert(core.string_to_pos("10.0, 5, -2").x == 10)
 554 assert(core.string_to_pos("( 10.0, 5, -2)").z == -2)
 555 assert(core.string_to_pos("asd, 5, -2)") == nil)
 556
 557 --------------------------------------------------------------------------------
 558 function table.copy(t, seen)
 559         local n = {}
 560         seen = seen or {}
 561         seen[t] = n
 562         for k, v in pairs(t) do
 563                 n[(type(k) == "table" and (seen[k] or table.copy(k, seen))) or k] =
 564                         (type(v) == "table" and (seen[v] or table.copy(v, seen))) or v
 565         end
 566         return n
 567 end
 568 --------------------------------------------------------------------------------
 569 -- mainmenu only functions
 570 --------------------------------------------------------------------------------
 571 if INIT == "mainmenu" then
 572         function core.get_game(index)
 573                 local games = game.get_games()
 574
 575                 if index > 0 and index <= #games then
 576                         return games[index]
 577                 end
 578
 579                 return nil
 580         end
 581
 582         function fgettext_ne(text, ...)
 583                 text = core.gettext(text)
 584                 local arg = {n=select('#', ...), ...}
 585                 if arg.n >= 1 then
 586                         -- Insert positional parameters ($1, $2, ...)
 587                         local result = ''
 588                         local pos = 1
 589                         while pos <= text:len() do
 590                                 local newpos = text:find('[$]', pos)
 591                                 if newpos == nil then
 592                                         result = result .. text:sub(pos)
 593                                         pos = text:len() + 1
 594                                 else
 595                                         local paramindex =
 596                                                 tonumber(text:sub(newpos+1, newpos+1))
 597                                         result = result .. text:sub(pos, newpos-1)
 598                                                 .. tostring(arg[paramindex])
 599                                         pos = newpos + 2
 600                                 end
 601                         end
 602                         text = result
 603                 end
 604                 return text
 605         end
 606
 607         function fgettext(text, ...)
 608                 return core.formspec_escape(fgettext_ne(text, ...))
 609         end
 610 end
 611