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 function string.split(str, delim, include_empty, max_splits, sep_is_pattern)
 163         delim = delim or ","
 164         max_splits = max_splits or -1
 165         local items = {}
 166         local pos, len, seplen = 1, #str, #delim
 167         local plain = not sep_is_pattern
 168         max_splits = max_splits + 1
 169         repeat
 170                 local np, npe = string_find(str, delim, pos, plain)
 171                 np, npe = (np or (len+1)), (npe or (len+1))
 172                 if (not np) or (max_splits == 1) then
 173                         np = len + 1
 174                         npe = np
 175                 end
 176                 local s = string_sub(str, pos, np - 1)
 177                 if include_empty or (s ~= "") then
 178                         max_splits = max_splits - 1
 179                         table_insert(items, s)
 180                 end
 181                 pos = npe + 1
 182         until (max_splits == 0) or (pos > (len + 1))
 183         return items
 184 end
 185
 186 --------------------------------------------------------------------------------
 187 function file_exists(filename)
 188         local f = io.open(filename, "r")
 189         if f==nil then
 190                 return false
 191         else
 192                 f:close()
 193                 return true
 194         end
 195 end
 196
 197 --------------------------------------------------------------------------------
 198 function string:trim()
 199         return (self:gsub("^%s*(.-)%s*$", "%1"))
 200 end
 201
 202 assert(string.trim("\n \t\tfoo bar\t ") == "foo bar")
 203
 204 --------------------------------------------------------------------------------
 205 function math.hypot(x, y)
 206         local t
 207         x = math.abs(x)
 208         y = math.abs(y)
 209         t = math.min(x, y)
 210         x = math.max(x, y)
 211         if x == 0 then return 0 end
 212         t = t / x
 213         return x * math.sqrt(1 + t * t)
 214 end
 215
 216 --------------------------------------------------------------------------------
 217 function math.sign(x, tolerance)
 218         tolerance = tolerance or 0
 219         if x > tolerance then
 220                 return 1
 221         elseif x < -tolerance then
 222                 return -1
 223         end
 224         return 0
 225 end
 226
 227 --------------------------------------------------------------------------------
 228 function get_last_folder(text,count)
 229         local parts = text:split(DIR_DELIM)
 230
 231         if count == nil then
 232                 return parts[#parts]
 233         end
 234
 235         local retval = ""
 236         for i=1,count,1 do
 237                 retval = retval .. parts[#parts - (count-i)] .. DIR_DELIM
 238         end
 239
 240         return retval
 241 end
 242
 243 --------------------------------------------------------------------------------
 244 function cleanup_path(temppath)
 245
 246         local parts = temppath:split("-")
 247         temppath = ""
 248         for i=1,#parts,1 do
 249                 if temppath ~= "" then
 250                         temppath = temppath .. "_"
 251                 end
 252                 temppath = temppath .. parts[i]
 253         end
 254
 255         parts = temppath:split(".")
 256         temppath = ""
 257         for i=1,#parts,1 do
 258                 if temppath ~= "" then
 259                         temppath = temppath .. "_"
 260                 end
 261                 temppath = temppath .. parts[i]
 262         end
 263
 264         parts = temppath:split("'")
 265         temppath = ""
 266         for i=1,#parts,1 do
 267                 if temppath ~= "" then
 268                         temppath = temppath .. ""
 269                 end
 270                 temppath = temppath .. parts[i]
 271         end
 272
 273         parts = temppath:split(" ")
 274         temppath = ""
 275         for i=1,#parts,1 do
 276                 if temppath ~= "" then
 277                         temppath = temppath
 278                 end
 279                 temppath = temppath .. parts[i]
 280         end
 281
 282         return temppath
 283 end
 284
 285 function core.formspec_escape(text)
 286         if text ~= nil then
 287                 text = string.gsub(text,"\\","\\\\")
 288                 text = string.gsub(text,"%]","\\]")
 289                 text = string.gsub(text,"%[","\\[")
 290                 text = string.gsub(text,";","\\;")
 291                 text = string.gsub(text,",","\\,")
 292         end
 293         return text
 294 end
 295
 296
 297 function core.splittext(text,charlimit)
 298         local retval = {}
 299
 300         local current_idx = 1
 301
 302         local start,stop = string_find(text, " ", current_idx)
 303         local nl_start,nl_stop = string_find(text, "\n", current_idx)
 304         local gotnewline = false
 305         if nl_start ~= nil and (start == nil or nl_start < start) then
 306                 start = nl_start
 307                 stop = nl_stop
 308                 gotnewline = true
 309         end
 310         local last_line = ""
 311         while start ~= nil do
 312                 if string.len(last_line) + (stop-start) > charlimit then
 313                         table_insert(retval, last_line)
 314                         last_line = ""
 315                 end
 316
 317                 if last_line ~= "" then
 318                         last_line = last_line .. " "
 319                 end
 320
 321                 last_line = last_line .. string_sub(text, current_idx, stop - 1)
 322
 323                 if gotnewline then
 324                         table_insert(retval, last_line)
 325                         last_line = ""
 326                         gotnewline = false
 327                 end
 328                 current_idx = stop+1
 329
 330                 start,stop = string_find(text, " ", current_idx)
 331                 nl_start,nl_stop = string_find(text, "\n", current_idx)
 332
 333                 if nl_start ~= nil and (start == nil or nl_start < start) then
 334                         start = nl_start
 335                         stop = nl_stop
 336                         gotnewline = true
 337                 end
 338         end
 339
 340         --add last part of text
 341         if string.len(last_line) + (string.len(text) - current_idx) > charlimit then
 342                         table_insert(retval, last_line)
 343                         table_insert(retval, string_sub(text, current_idx))
 344         else
 345                 last_line = last_line .. " " .. string_sub(text, current_idx)
 346                 table_insert(retval, last_line)
 347         end
 348
 349         return retval
 350 end
 351
 352 --------------------------------------------------------------------------------
 353
 354 if INIT == "game" then
 355         local dirs1 = {9, 18, 7, 12}
 356         local dirs2 = {20, 23, 22, 21}
 357
 358         function core.rotate_and_place(itemstack, placer, pointed_thing,
 359                                 infinitestacks, orient_flags)
 360                 orient_flags = orient_flags or {}
 361
 362                 local unode = core.get_node_or_nil(pointed_thing.under)
 363                 if not unode then
 364                         return
 365                 end
 366                 local undef = core.registered_nodes[unode.name]
 367                 if undef and undef.on_rightclick then
 368                         undef.on_rightclick(pointed_thing.under, unode, placer,
 369                                         itemstack, pointed_thing)
 370                         return
 371                 end
 372                 local pitch = placer:get_look_pitch()
 373                 local fdir = core.dir_to_facedir(placer:get_look_dir())
 374                 local wield_name = itemstack:get_name()
 375
 376                 local above = pointed_thing.above
 377                 local under = pointed_thing.under
 378                 local iswall = (above.y == under.y)
 379                 local isceiling = not iswall and (above.y < under.y)
 380                 local anode = core.get_node_or_nil(above)
 381                 if not anode then
 382                         return
 383                 end
 384                 local pos = pointed_thing.above
 385                 local node = anode
 386
 387                 if undef and undef.buildable_to then
 388                         pos = pointed_thing.under
 389                         node = unode
 390                         iswall = false
 391                 end
 392
 393                 if core.is_protected(pos, placer:get_player_name()) then
 394                         core.record_protection_violation(pos,
 395                                         placer:get_player_name())
 396                         return
 397                 end
 398
 399                 local ndef = core.registered_nodes[node.name]
 400                 if not ndef or not ndef.buildable_to then
 401                         return
 402                 end
 403
 404                 if orient_flags.force_floor then
 405                         iswall = false
 406                         isceiling = false
 407                 elseif orient_flags.force_ceiling then
 408                         iswall = false
 409                         isceiling = true
 410                 elseif orient_flags.force_wall then
 411                         iswall = true
 412                         isceiling = false
 413                 elseif orient_flags.invert_wall then
 414                         iswall = not iswall
 415                 end
 416
 417                 if iswall then
 418                         core.set_node(pos, {name = wield_name,
 419                                         param2 = dirs1[fdir+1]})
 420                 elseif isceiling then
 421                         if orient_flags.force_facedir then
 422                                 core.set_node(pos, {name = wield_name,
 423                                                 param2 = 20})
 424                         else
 425                                 core.set_node(pos, {name = wield_name,
 426                                                 param2 = dirs2[fdir+1]})
 427                         end
 428                 else -- place right side up
 429                         if orient_flags.force_facedir then
 430                                 core.set_node(pos, {name = wield_name,
 431                                                 param2 = 0})
 432                         else
 433                                 core.set_node(pos, {name = wield_name,
 434                                                 param2 = fdir})
 435                         end
 436                 end
 437
 438                 if not infinitestacks then
 439                         itemstack:take_item()
 440                         return itemstack
 441                 end
 442         end
 443
 444
 445 --------------------------------------------------------------------------------
 446 --Wrapper for rotate_and_place() to check for sneak and assume Creative mode
 447 --implies infinite stacks when performing a 6d rotation.
 448 --------------------------------------------------------------------------------
 449
 450
 451         core.rotate_node = function(itemstack, placer, pointed_thing)
 452                 core.rotate_and_place(itemstack, placer, pointed_thing,
 453                                 core.setting_getbool("creative_mode"),
 454                                 {invert_wall = placer:get_player_control().sneak})
 455                 return itemstack
 456         end
 457 end
 458
 459 --------------------------------------------------------------------------------
 460 function core.explode_table_event(evt)
 461         if evt ~= nil then
 462                 local parts = evt:split(":")
 463                 if #parts == 3 then
 464                         local t = parts[1]:trim()
 465                         local r = tonumber(parts[2]:trim())
 466                         local c = tonumber(parts[3]:trim())
 467                         if type(r) == "number" and type(c) == "number"
 468                                         and t ~= "INV" then
 469                                 return {type=t, row=r, column=c}
 470                         end
 471                 end
 472         end
 473         return {type="INV", row=0, column=0}
 474 end
 475
 476 --------------------------------------------------------------------------------
 477 function core.explode_textlist_event(evt)
 478         if evt ~= nil then
 479                 local parts = evt:split(":")
 480                 if #parts == 2 then
 481                         local t = parts[1]:trim()
 482                         local r = tonumber(parts[2]:trim())
 483                         if type(r) == "number" and t ~= "INV" then
 484                                 return {type=t, index=r}
 485                         end
 486                 end
 487         end
 488         return {type="INV", index=0}
 489 end
 490
 491 --------------------------------------------------------------------------------
 492 function core.explode_scrollbar_event(evt)
 493         local retval = core.explode_textlist_event(evt)
 494
 495         retval.value = retval.index
 496         retval.index = nil
 497
 498         return retval
 499 end
 500
 501 --------------------------------------------------------------------------------
 502 function core.pos_to_string(pos, decimal_places)
 503         local x = pos.x
 504         local y = pos.y
 505         local z = pos.z
 506         if decimal_places ~= nil then
 507                 x = string.format("%." .. decimal_places .. "f", x)
 508                 y = string.format("%." .. decimal_places .. "f", y)
 509                 z = string.format("%." .. decimal_places .. "f", z)
 510         end
 511         return "(" .. x .. "," .. y .. "," .. z .. ")"
 512 end
 513
 514 --------------------------------------------------------------------------------
 515 function core.string_to_pos(value)
 516         if value == nil then
 517                 return nil
 518         end
 519
 520         local p = {}
 521         p.x, p.y, p.z = string.match(value, "^([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+)$")
 522         if p.x and p.y and p.z then
 523                 p.x = tonumber(p.x)
 524                 p.y = tonumber(p.y)
 525                 p.z = tonumber(p.z)
 526                 return p
 527         end
 528         local p = {}
 529         p.x, p.y, p.z = string.match(value, "^%( *([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+) *%)$")
 530         if p.x and p.y and p.z then
 531                 p.x = tonumber(p.x)
 532                 p.y = tonumber(p.y)
 533                 p.z = tonumber(p.z)
 534                 return p
 535         end
 536         return nil
 537 end
 538
 539 assert(core.string_to_pos("10.0, 5, -2").x == 10)
 540 assert(core.string_to_pos("( 10.0, 5, -2)").z == -2)
 541 assert(core.string_to_pos("asd, 5, -2)") == nil)
 542
 543 --------------------------------------------------------------------------------
 544 function table.copy(t, seen)
 545         local n = {}
 546         seen = seen or {}
 547         seen[t] = n
 548         for k, v in pairs(t) do
 549                 n[(type(k) == "table" and (seen[k] or table.copy(k, seen))) or k] =
 550                         (type(v) == "table" and (seen[v] or table.copy(v, seen))) or v
 551         end
 552         return n
 553 end
 554 --------------------------------------------------------------------------------
 555 -- mainmenu only functions
 556 --------------------------------------------------------------------------------
 557 if INIT == "mainmenu" then
 558         function core.get_game(index)
 559                 local games = game.get_games()
 560
 561                 if index > 0 and index <= #games then
 562                         return games[index]
 563                 end
 564
 565                 return nil
 566         end
 567
 568         function fgettext_ne(text, ...)
 569                 text = core.gettext(text)
 570                 local arg = {n=select('#', ...), ...}
 571                 if arg.n >= 1 then
 572                         -- Insert positional parameters ($1, $2, ...)
 573                         local result = ''
 574                         local pos = 1
 575                         while pos <= text:len() do
 576                                 local newpos = text:find('[$]', pos)
 577                                 if newpos == nil then
 578                                         result = result .. text:sub(pos)
 579                                         pos = text:len() + 1
 580                                 else
 581                                         local paramindex =
 582                                                 tonumber(text:sub(newpos+1, newpos+1))
 583                                         result = result .. text:sub(pos, newpos-1)
 584                                                 .. tostring(arg[paramindex])
 585                                         pos = newpos + 2
 586                                 end
 587                         end
 588                         text = result
 589                 end
 590                 return text
 591         end
 592
 593         function fgettext(text, ...)
 594                 return core.formspec_escape(fgettext_ne(text, ...))
 595         end
 596 end
 597