builtin/common/misc_helpers.lua

   1 -- Minetest: builtin/misc_helpers.lua
   2
   3 --------------------------------------------------------------------------------
   4 -- Localize functions to avoid table lookups (better performance).
   5 local string_sub, string_find = string.sub, string.find
   6
   7 --------------------------------------------------------------------------------
   8 function basic_dump(o)
   9         local tp = type(o)
  10         if tp == "number" then
  11                 return tostring(o)
  12         elseif tp == "string" then
  13                 return string.format("%q", o)
  14         elseif tp == "boolean" then
  15                 return tostring(o)
  16         elseif tp == "nil" then
  17                 return "nil"
  18         -- Uncomment for full function dumping support.
  19         -- Not currently enabled because bytecode isn't very human-readable and
  20         -- dump's output is intended for humans.
  21         --elseif tp == "function" then
  22         --      return string.format("loadstring(%q)", string.dump(o))
  23         else
  24                 return string.format("<%s>", tp)
  25         end
  26 end
  27
  28 local keywords = {
  29         ["and"] = true,
  30         ["break"] = true,
  31         ["do"] = true,
  32         ["else"] = true,
  33         ["elseif"] = true,
  34         ["end"] = true,
  35         ["false"] = true,
  36         ["for"] = true,
  37         ["function"] = true,
  38         ["goto"] = true,  -- Lua 5.2
  39         ["if"] = true,
  40         ["in"] = true,
  41         ["local"] = true,
  42         ["nil"] = true,
  43         ["not"] = true,
  44         ["or"] = true,
  45         ["repeat"] = true,
  46         ["return"] = true,
  47         ["then"] = true,
  48         ["true"] = true,
  49         ["until"] = true,
  50         ["while"] = true,
  51 }
  52 local function is_valid_identifier(str)
  53         if not str:find("^[a-zA-Z_][a-zA-Z0-9_]*$") or keywords[str] then
  54                 return false
  55         end
  56         return true
  57 end
  58
  59 --------------------------------------------------------------------------------
  60 -- Dumps values in a line-per-value format.
  61 -- For example, {test = {"Testing..."}} becomes:
  62 --   _["test"] = {}
  63 --   _["test"][1] = "Testing..."
  64 -- This handles tables as keys and circular references properly.
  65 -- It also handles multiple references well, writing the table only once.
  66 -- The dumped argument is internal-only.
  67
  68 function dump2(o, name, dumped)
  69         name = name or "_"
  70         -- "dumped" is used to keep track of serialized tables to handle
  71         -- multiple references and circular tables properly.
  72         -- It only contains tables as keys.  The value is the name that
  73         -- the table has in the dump, eg:
  74         -- {x = {"y"}} -> dumped[{"y"}] = '_["x"]'
  75         dumped = dumped or {}
  76         if type(o) ~= "table" then
  77                 return string.format("%s = %s\n", name, basic_dump(o))
  78         end
  79         if dumped[o] then
  80                 return string.format("%s = %s\n", name, dumped[o])
  81         end
  82         dumped[o] = name
  83         -- This contains a list of strings to be concatenated later (because
  84         -- Lua is slow at individual concatenation).
  85         local t = {}
  86         for k, v in pairs(o) do
  87                 local keyStr
  88                 if type(k) == "table" then
  89                         if dumped[k] then
  90                                 keyStr = dumped[k]
  91                         else
  92                                 -- Key tables don't have a name, so use one of
  93                                 -- the form _G["table: 0xFFFFFFF"]
  94                                 keyStr = string.format("_G[%q]", tostring(k))
  95                                 -- Dump key table
  96                                 t[#t + 1] = dump2(k, keyStr, dumped)
  97                         end
  98                 else
  99                         keyStr = basic_dump(k)
 100                 end
 101                 local vname = string.format("%s[%s]", name, keyStr)
 102                 t[#t + 1] = dump2(v, vname, dumped)
 103         end
 104         return string.format("%s = {}\n%s", name, table.concat(t))
 105 end
 106
 107 --------------------------------------------------------------------------------
 108 -- This dumps values in a one-statement format.
 109 -- For example, {test = {"Testing..."}} becomes:
 110 -- [[{
 111 --      test = {
 112 --              "Testing..."
 113 --      }
 114 -- }]]
 115 -- This supports tables as keys, but not circular references.
 116 -- It performs poorly with multiple references as it writes out the full
 117 -- table each time.
 118 -- The indent field specifies a indentation string, it defaults to a tab.
 119 -- Use the empty string to disable indentation.
 120 -- The dumped and level arguments are internal-only.
 121
 122 function dump(o, indent, nested, level)
 123         if type(o) ~= "table" then
 124                 return basic_dump(o)
 125         end
 126         -- Contains table -> true/nil of currently nested tables
 127         nested = nested or {}
 128         if nested[o] then
 129                 return "<circular reference>"
 130         end
 131         nested[o] = true
 132         indent = indent or "\t"
 133         level = level or 1
 134         local t = {}
 135         local dumped_indexes = {}
 136         for i, v in ipairs(o) do
 137                 t[#t + 1] = dump(v, indent, nested, level + 1)
 138                 dumped_indexes[i] = true
 139         end
 140         for k, v in pairs(o) do
 141                 if not dumped_indexes[k] then
 142                         if type(k) ~= "string" or not is_valid_identifier(k) then
 143                                 k = "["..dump(k, indent, nested, level + 1).."]"
 144                         end
 145                         v = dump(v, indent, nested, level + 1)
 146                         t[#t + 1] = k.." = "..v
 147                 end
 148         end
 149         nested[o] = nil
 150         if indent ~= "" then
 151                 local indent_str = "\n"..string.rep(indent, level)
 152                 local end_indent_str = "\n"..string.rep(indent, level - 1)
 153                 return string.format("{%s%s%s}",
 154                                 indent_str,
 155                                 table.concat(t, ","..indent_str),
 156                                 end_indent_str)
 157         end
 158         return "{"..table.concat(t, ", ").."}"
 159 end
 160
 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                         items[#items + 1] = 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 table.indexof(list, val)
 188         for i, v in ipairs(list) do
 189                 if v == val then
 190                         return i
 191                 end
 192         end
 193         return -1
 194 end
 195
 196 assert(table.indexof({"foo", "bar"}, "foo") == 1)
 197 assert(table.indexof({"foo", "bar"}, "baz") == -1)
 198
 199 --------------------------------------------------------------------------------
 200 function file_exists(filename)
 201         local f = io.open(filename, "r")
 202         if f == nil then
 203                 return false
 204         else
 205                 f:close()
 206                 return true
 207         end
 208 end
 209
 210 --------------------------------------------------------------------------------
 211 function string:trim()
 212         return (self:gsub("^%s*(.-)%s*$", "%1"))
 213 end
 214
 215 assert(string.trim("\n \t\tfoo bar\t ") == "foo bar")
 216
 217 --------------------------------------------------------------------------------
 218 function math.hypot(x, y)
 219         local t
 220         x = math.abs(x)
 221         y = math.abs(y)
 222         t = math.min(x, y)
 223         x = math.max(x, y)
 224         if x == 0 then return 0 end
 225         t = t / x
 226         return x * math.sqrt(1 + t * t)
 227 end
 228
 229 --------------------------------------------------------------------------------
 230 function math.sign(x, tolerance)
 231         tolerance = tolerance or 0
 232         if x > tolerance then
 233                 return 1
 234         elseif x < -tolerance then
 235                 return -1
 236         end
 237         return 0
 238 end
 239
 240 --------------------------------------------------------------------------------
 241 function get_last_folder(text,count)
 242         local parts = text:split(DIR_DELIM)
 243
 244         if count == nil then
 245                 return parts[#parts]
 246         end
 247
 248         local retval = ""
 249         for i=1,count,1 do
 250                 retval = retval .. parts[#parts - (count-i)] .. DIR_DELIM
 251         end
 252
 253         return retval
 254 end
 255
 256 --------------------------------------------------------------------------------
 257 function cleanup_path(temppath)
 258
 259         local parts = temppath:split("-")
 260         temppath = ""
 261         for i=1,#parts,1 do
 262                 if temppath ~= "" then
 263                         temppath = temppath .. "_"
 264                 end
 265                 temppath = temppath .. parts[i]
 266         end
 267
 268         parts = temppath:split(".")
 269         temppath = ""
 270         for i=1,#parts,1 do
 271                 if temppath ~= "" then
 272                         temppath = temppath .. "_"
 273                 end
 274                 temppath = temppath .. parts[i]
 275         end
 276
 277         parts = temppath:split("'")
 278         temppath = ""
 279         for i=1,#parts,1 do
 280                 if temppath ~= "" then
 281                         temppath = temppath .. ""
 282                 end
 283                 temppath = temppath .. parts[i]
 284         end
 285
 286         parts = temppath:split(" ")
 287         temppath = ""
 288         for i=1,#parts,1 do
 289                 if temppath ~= "" then
 290                         temppath = temppath
 291                 end
 292                 temppath = temppath .. parts[i]
 293         end
 294
 295         return temppath
 296 end
 297
 298 function core.formspec_escape(text)
 299         if text ~= nil then
 300                 text = string.gsub(text,"\\","\\\\")
 301                 text = string.gsub(text,"%]","\\]")
 302                 text = string.gsub(text,"%[","\\[")
 303                 text = string.gsub(text,";","\\;")
 304                 text = string.gsub(text,",","\\,")
 305         end
 306         return text
 307 end
 308
 309
 310 function core.splittext(text,charlimit)
 311         local retval = {}
 312
 313         local current_idx = 1
 314
 315         local start,stop = string_find(text, " ", current_idx)
 316         local nl_start,nl_stop = string_find(text, "\n", current_idx)
 317         local gotnewline = false
 318         if nl_start ~= nil and (start == nil or nl_start < start) then
 319                 start = nl_start
 320                 stop = nl_stop
 321                 gotnewline = true
 322         end
 323         local last_line = ""
 324         while start ~= nil do
 325                 if string.len(last_line) + (stop-start) > charlimit then
 326                         retval[#retval + 1] = last_line
 327                         last_line = ""
 328                 end
 329
 330                 if last_line ~= "" then
 331                         last_line = last_line .. " "
 332                 end
 333
 334                 last_line = last_line .. string_sub(text, current_idx, stop - 1)
 335
 336                 if gotnewline then
 337                         retval[#retval + 1] = last_line
 338                         last_line = ""
 339                         gotnewline = false
 340                 end
 341                 current_idx = stop+1
 342
 343                 start,stop = string_find(text, " ", current_idx)
 344                 nl_start,nl_stop = string_find(text, "\n", current_idx)
 345
 346                 if nl_start ~= nil and (start == nil or nl_start < start) then
 347                         start = nl_start
 348                         stop = nl_stop
 349                         gotnewline = true
 350                 end
 351         end
 352
 353         --add last part of text
 354         if string.len(last_line) + (string.len(text) - current_idx) > charlimit then
 355                         retval[#retval + 1] = last_line
 356                         retval[#retval + 1] = string_sub(text, current_idx)
 357         else
 358                 last_line = last_line .. " " .. string_sub(text, current_idx)
 359                 retval[#retval + 1] = last_line
 360         end
 361
 362         return retval
 363 end
 364
 365 --------------------------------------------------------------------------------
 366
 367 if INIT == "game" then
 368         local dirs1 = {9, 18, 7, 12}
 369         local dirs2 = {20, 23, 22, 21}
 370
 371         function core.rotate_and_place(itemstack, placer, pointed_thing,
 372                                 infinitestacks, orient_flags)
 373                 orient_flags = orient_flags or {}
 374
 375                 local unode = core.get_node_or_nil(pointed_thing.under)
 376                 if not unode then
 377                         return
 378                 end
 379                 local undef = core.registered_nodes[unode.name]
 380                 if undef and undef.on_rightclick then
 381                         undef.on_rightclick(pointed_thing.under, unode, placer,
 382                                         itemstack, pointed_thing)
 383                         return
 384                 end
 385                 local fdir = core.dir_to_facedir(placer:get_look_dir())
 386                 local wield_name = itemstack:get_name()
 387
 388                 local above = pointed_thing.above
 389                 local under = pointed_thing.under
 390                 local iswall = (above.y == under.y)
 391                 local isceiling = not iswall and (above.y < under.y)
 392                 local anode = core.get_node_or_nil(above)
 393                 if not anode then
 394                         return
 395                 end
 396                 local pos = pointed_thing.above
 397                 local node = anode
 398
 399                 if undef and undef.buildable_to then
 400                         pos = pointed_thing.under
 401                         node = unode
 402                         iswall = false
 403                 end
 404
 405                 if core.is_protected(pos, placer:get_player_name()) then
 406                         core.record_protection_violation(pos,
 407                                         placer:get_player_name())
 408                         return
 409                 end
 410
 411                 local ndef = core.registered_nodes[node.name]
 412                 if not ndef or not ndef.buildable_to then
 413                         return
 414                 end
 415
 416                 if orient_flags.force_floor then
 417                         iswall = false
 418                         isceiling = false
 419                 elseif orient_flags.force_ceiling then
 420                         iswall = false
 421                         isceiling = true
 422                 elseif orient_flags.force_wall then
 423                         iswall = true
 424                         isceiling = false
 425                 elseif orient_flags.invert_wall then
 426                         iswall = not iswall
 427                 end
 428
 429                 if iswall then
 430                         core.set_node(pos, {name = wield_name,
 431                                         param2 = dirs1[fdir + 1]})
 432                 elseif isceiling then
 433                         if orient_flags.force_facedir then
 434                                 core.set_node(pos, {name = wield_name,
 435                                                 param2 = 20})
 436                         else
 437                                 core.set_node(pos, {name = wield_name,
 438                                                 param2 = dirs2[fdir + 1]})
 439                         end
 440                 else -- place right side up
 441                         if orient_flags.force_facedir then
 442                                 core.set_node(pos, {name = wield_name,
 443                                                 param2 = 0})
 444                         else
 445                                 core.set_node(pos, {name = wield_name,
 446                                                 param2 = fdir})
 447                         end
 448                 end
 449
 450                 if not infinitestacks then
 451                         itemstack:take_item()
 452                         return itemstack
 453                 end
 454         end
 455
 456
 457 --------------------------------------------------------------------------------
 458 --Wrapper for rotate_and_place() to check for sneak and assume Creative mode
 459 --implies infinite stacks when performing a 6d rotation.
 460 --------------------------------------------------------------------------------
 461
 462
 463         core.rotate_node = function(itemstack, placer, pointed_thing)
 464                 core.rotate_and_place(itemstack, placer, pointed_thing,
 465                                 core.setting_getbool("creative_mode"),
 466                                 {invert_wall = placer:get_player_control().sneak})
 467                 return itemstack
 468         end
 469 end
 470
 471 --------------------------------------------------------------------------------
 472 function core.explode_table_event(evt)
 473         if evt ~= nil then
 474                 local parts = evt:split(":")
 475                 if #parts == 3 then
 476                         local t = parts[1]:trim()
 477                         local r = tonumber(parts[2]:trim())
 478                         local c = tonumber(parts[3]:trim())
 479                         if type(r) == "number" and type(c) == "number"
 480                                         and t ~= "INV" then
 481                                 return {type=t, row=r, column=c}
 482                         end
 483                 end
 484         end
 485         return {type="INV", row=0, column=0}
 486 end
 487
 488 --------------------------------------------------------------------------------
 489 function core.explode_textlist_event(evt)
 490         if evt ~= nil then
 491                 local parts = evt:split(":")
 492                 if #parts == 2 then
 493                         local t = parts[1]:trim()
 494                         local r = tonumber(parts[2]:trim())
 495                         if type(r) == "number" and t ~= "INV" then
 496                                 return {type=t, index=r}
 497                         end
 498                 end
 499         end
 500         return {type="INV", index=0}
 501 end
 502
 503 --------------------------------------------------------------------------------
 504 function core.explode_scrollbar_event(evt)
 505         local retval = core.explode_textlist_event(evt)
 506
 507         retval.value = retval.index
 508         retval.index = nil
 509
 510         return retval
 511 end
 512
 513 --------------------------------------------------------------------------------
 514 function core.pos_to_string(pos, decimal_places)
 515         local x = pos.x
 516         local y = pos.y
 517         local z = pos.z
 518         if decimal_places ~= nil then
 519                 x = string.format("%." .. decimal_places .. "f", x)
 520                 y = string.format("%." .. decimal_places .. "f", y)
 521                 z = string.format("%." .. decimal_places .. "f", z)
 522         end
 523         return "(" .. x .. "," .. y .. "," .. z .. ")"
 524 end
 525
 526 --------------------------------------------------------------------------------
 527 function core.string_to_pos(value)
 528         if value == nil then
 529                 return nil
 530         end
 531
 532         local p = {}
 533         p.x, p.y, p.z = string.match(value, "^([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+)$")
 534         if p.x and p.y and p.z then
 535                 p.x = tonumber(p.x)
 536                 p.y = tonumber(p.y)
 537                 p.z = tonumber(p.z)
 538                 return p
 539         end
 540         local p = {}
 541         p.x, p.y, p.z = string.match(value, "^%( *([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+) *%)$")
 542         if p.x and p.y and p.z then
 543                 p.x = tonumber(p.x)
 544                 p.y = tonumber(p.y)
 545                 p.z = tonumber(p.z)
 546                 return p
 547         end
 548         return nil
 549 end
 550
 551 assert(core.string_to_pos("10.0, 5, -2").x == 10)
 552 assert(core.string_to_pos("( 10.0, 5, -2)").z == -2)
 553 assert(core.string_to_pos("asd, 5, -2)") == nil)
 554
 555 --------------------------------------------------------------------------------
 556 function core.string_to_area(value)
 557         local p1, p2 = unpack(value:split(") ("))
 558         if p1 == nil or p2 == nil then
 559                 return nil
 560         end
 561
 562         p1 = core.string_to_pos(p1 .. ")")
 563         p2 = core.string_to_pos("(" .. p2)
 564         if p1 == nil or p2 == nil then
 565                 return nil
 566         end
 567
 568         return p1, p2
 569 end
 570
 571 local function test_string_to_area()
 572         local p1, p2 = core.string_to_area("(10.0, 5, -2) (  30.2,   4, -12.53)")
 573         assert(p1.x == 10.0 and p1.y == 5 and p1.z == -2)
 574         assert(p2.x == 30.2 and p2.y == 4 and p2.z == -12.53)
 575
 576         p1, p2 = core.string_to_area("(10.0, 5, -2  30.2,   4, -12.53")
 577         assert(p1 == nil and p2 == nil)
 578
 579         p1, p2 = core.string_to_area("(10.0, 5,) -2  fgdf2,   4, -12.53")
 580         assert(p1 == nil and p2 == nil)
 581 end
 582
 583 test_string_to_area()
 584
 585 --------------------------------------------------------------------------------
 586 function table.copy(t, seen)
 587         local n = {}
 588         seen = seen or {}
 589         seen[t] = n
 590         for k, v in pairs(t) do
 591                 n[(type(k) == "table" and (seen[k] or table.copy(k, seen))) or k] =
 592                         (type(v) == "table" and (seen[v] or table.copy(v, seen))) or v
 593         end
 594         return n
 595 end
 596 --------------------------------------------------------------------------------
 597 -- mainmenu only functions
 598 --------------------------------------------------------------------------------
 599 if INIT == "mainmenu" then
 600         function core.get_game(index)
 601                 local games = game.get_games()
 602
 603                 if index > 0 and index <= #games then
 604                         return games[index]
 605                 end
 606
 607                 return nil
 608         end
 609
 610         function fgettext_ne(text, ...)
 611                 text = core.gettext(text)
 612                 local arg = {n=select('#', ...), ...}
 613                 if arg.n >= 1 then
 614                         -- Insert positional parameters ($1, $2, ...)
 615                         local result = ''
 616                         local pos = 1
 617                         while pos <= text:len() do
 618                                 local newpos = text:find('[$]', pos)
 619                                 if newpos == nil then
 620                                         result = result .. text:sub(pos)
 621                                         pos = text:len() + 1
 622                                 else
 623                                         local paramindex =
 624                                                 tonumber(text:sub(newpos+1, newpos+1))
 625                                         result = result .. text:sub(pos, newpos-1)
 626                                                 .. tostring(arg[paramindex])
 627                                         pos = newpos + 2
 628                                 end
 629                         end
 630                         text = result
 631                 end
 632                 return text
 633         end
 634
 635         function fgettext(text, ...)
 636                 return core.formspec_escape(fgettext_ne(text, ...))
 637         end
 638 end
 639