Add support for Lua 5.2

Includes aliases to functions deprecated in Lua 5.2, such as
math.log10 and unpack, and loadstring

DiskFile.c

@@ -80,6 +80,6 @@ void torch_DiskFile_init(lua_State *L)
   luaT_newmetatable(L, "torch.DiskFile", "torch.File",
                     torch_DiskFile_new, torch_DiskFile_free, NULL);
 
-  luaL_register(L, NULL, torch_DiskFile__);
+  luaT_setfuncs(L, torch_DiskFile__, 0);
   lua_pop(L, 1);
 }

File.c

@@ -199,6 +199,6 @@ static const struct luaL_Reg torch_File__ [] = {
 void torch_File_init(lua_State *L)
 {
   luaT_newmetatable(L, "torch.File", NULL, NULL, NULL, NULL);
-  luaL_register(L, NULL, torch_File__);
+  luaT_setfuncs(L, torch_File__, 0);
   lua_pop(L, 1);
 }

File.lua

@@ -21,6 +21,9 @@ local TYPE_BOOLEAN  = 5
 local TYPE_FUNCTION = 6
 local TYPE_RECUR_FUNCTION = 7
 
+-- Lua 5.2 compatibility
+local loadstring = loadstring or load
+
 function File:isWritableObject(object)
    local typename = type(object)
    local typeidx

Generator.c

@@ -24,6 +24,6 @@ void torch_Generator_init(lua_State *L)
 {
   luaT_newmetatable(L, torch_Generator, NULL,
                     torch_Generator_new, torch_Generator_free, torch_Generator_factory);
-  luaL_register(L, NULL, torch_Generator_table_);
+  luaT_setfuncs(L, torch_Generator_table_, 0);
   lua_pop(L, 1);
 }

MemoryFile.c

@@ -56,6 +56,6 @@ void torch_MemoryFile_init(lua_State *L)
 {
   luaT_newmetatable(L, "torch.MemoryFile", "torch.File",
                     torch_MemoryFile_new, torch_MemoryFile_free, NULL);
-  luaL_register(L, NULL, torch_MemoryFile__);
+  luaT_setfuncs(L, torch_MemoryFile__, 0);
   lua_pop(L, 1);
 }

PipeFile.c

@@ -38,6 +38,6 @@ void torch_PipeFile_init(lua_State *L)
 {
   luaT_newmetatable(L, "torch.PipeFile", "torch.DiskFile",
                     torch_PipeFile_new, torch_PipeFile_free, NULL);
-  luaL_register(L, NULL, torch_PipeFile__);
+  luaT_setfuncs(L, torch_PipeFile__, 0);
   lua_pop(L, 1);
 }

Tensor.lua

@@ -7,6 +7,9 @@ local Tensor = {}
 -- types
 local types = {'Byte', 'Char', 'Short', 'Int', 'Long', 'Float', 'Double'}
 
+-- Lua 5.2 compatibility
+local log10 = math.log10 or function(x) return math.log(x, 10) end
+
 -- tostring() functions for Tensor and Storage
 local function Storage__printformat(self)
    if self:size() == 0 then 
@@ -25,13 +28,13 @@ local function Storage__printformat(self)
    local tensor = torch.DoubleTensor(torch.DoubleStorage(self:size()):copy(self), 1, self:size()):abs()
    local expMin = tensor:min()
    if expMin ~= 0 then
-      expMin = math.floor(math.log10(expMin)) + 1
+      expMin = math.floor(log10(expMin)) + 1
    else
       expMin = 1
    end
    local expMax = tensor:max()
    if expMax ~= 0 then
-      expMax = math.floor(math.log10(expMax)) + 1
+      expMax = math.floor(log10(expMax)) + 1
    else
       expMax = 1
    end

TensorMath.lua

@@ -120,7 +120,8 @@ local function wrap(...)
          end
       end
    end
-   method:wrap(unpack(args))
+   local unpack = unpack or table.unpack
+    method:wrap(unpack(args))
 end
 
 local reals = {ByteTensor='unsigned char',
@@ -1133,12 +1134,12 @@ static void torch_TensorMath_init(lua_State *L)
   luaT_pushmetatable(L, "torch.Tensor");
 
   /* register methods */
-  luaL_register(L, NULL, m_torch_TensorMath__);
+  luaT_setfuncs(L, m_torch_TensorMath__, 0);
 
   /* register functions into the "torch" field of the tensor metaclass */
   lua_pushstring(L, "torch");
   lua_newtable(L);
-  luaL_register(L, NULL, torch_TensorMath__);
+  luaT_setfuncs(L, torch_TensorMath__, 0);
   lua_rawset(L, -3);
   lua_pop(L, 1);
 }
@@ -1157,7 +1158,7 @@ void torch_TensorMath_init(lua_State *L)
   torch_LongTensorMath_init(L);
   torch_FloatTensorMath_init(L);
   torch_DoubleTensorMath_init(L);
-  luaL_register(L, NULL, torch_TensorMath__);
+  luaT_setfuncs(L, torch_TensorMath__, 0);
 }
 ]])
 

Timer.c

@@ -165,6 +165,6 @@ static const struct luaL_Reg torch_Timer__ [] = {
 void torch_Timer_init(lua_State *L)
 {
   luaT_newmetatable(L, "torch.Timer", NULL, torch_Timer_new, torch_Timer_free, NULL);
-  luaL_register(L, NULL, torch_Timer__);
+  luaT_setfuncs(L, torch_Timer__, 0);
   lua_pop(L, 1);
 }

generic/Storage.c

@@ -273,7 +273,7 @@ void torch_Storage_(init)(lua_State *L)
 {
   luaT_newmetatable(L, torch_Storage, NULL,
                     torch_Storage_(new), torch_Storage_(free), torch_Storage_(factory));
-  luaL_register(L, NULL, torch_Storage_(_));
+  luaT_setfuncs(L, torch_Storage_(_), 0);
   lua_pop(L, 1);
 }
 

generic/Tensor.c

@@ -1278,7 +1278,7 @@ void torch_Tensor_(init)(lua_State *L)
 {
   luaT_newmetatable(L, torch_Tensor, NULL,
                     torch_Tensor_(new), torch_Tensor_(free), torch_Tensor_(factory));
-  luaL_register(L, NULL, torch_Tensor_(_));
+  luaT_setfuncs(L, torch_Tensor_(_), 0);
   lua_pop(L, 1);
 }
 

generic/TensorOperator.c

@@ -166,7 +166,7 @@ static const struct luaL_Reg torch_TensorOperator_(_) [] = {
 void torch_TensorOperator_(init)(lua_State *L)
 {
   luaT_pushmetatable(L, torch_Tensor);
-  luaL_register(L, NULL, torch_TensorOperator_(_));
+  luaT_setfuncs(L, torch_TensorOperator_(_), 0);
   lua_pop(L, 1);
 }
 

init.c

@@ -56,7 +56,7 @@ int luaopen_libtorch(lua_State *L)
 
   lua_newtable(L);
   lua_pushvalue(L, -1);
-  lua_setfield(L, LUA_GLOBALSINDEX, "torch");
+  lua_setglobal(L, "torch");
 
   torch_File_init(L);
 

init.lua

@@ -6,6 +6,9 @@
 if not string.gfind then
     string.gfind = string.gmatch
 end
+if not table.unpack then
+    table.unpack = unpack
+end
 
 require "paths"
 paths.require "libtorch"

lib/luaT/luaT.c

@@ -45,6 +45,24 @@ void luaT_free(lua_State *L, void *ptr)
   free(ptr);
 }
 
+void luaT_setfuncs(lua_State *L, const luaL_Reg *l, int nup)
+{
+#if LUA_VERSION_NUM == 501
+  luaL_checkstack(L, nup+1, "too many upvalues");
+  for (; l->name != NULL; l++) {  /* fill the table with given functions */
+    int i;
+    lua_pushstring(L, l->name);
+    for (i = 0; i < nup; i++)  /* copy upvalues to the top */
+      lua_pushvalue(L, -(nup+1));
+    lua_pushcclosure(L, l->func, nup);  /* closure with those upvalues */
+    lua_settable(L, -(nup + 3));
+  }
+  lua_pop(L, nup);  /* remove upvalues */
+#else
+  luaL_setfuncs(L, l, nup);
+#endif
+}
+
 void luaT_stackdump(lua_State *L)
 {
   int i;
@@ -159,8 +177,8 @@ const char *luaT_typenameid(lua_State *L, const char *tname)
 }
 
 static const char cdataname[] = ""
-  "local _, ffi = pcall(require, 'ffi')\n"
-  "if ffi then\n"
+  "local ok, ffi = pcall(require, 'ffi')\n"
+  "if ok then\n"
   "  local id2name = {}\n"
   "  return function(cdata, name)\n"
   "    local id\n"
@@ -215,8 +233,8 @@ static const char* luaT_cdataname(lua_State *L, int ud, const char *tname)
 
 static void* CDATA_MT_KEY = &CDATA_MT_KEY;
 static const char cdatamt[] = ""
-  "local _, ffi = pcall(require, 'ffi')\n"
-  "if ffi and not jit then\n"
+  "local ok, ffi = pcall(require, 'ffi')\n"
+  "if ok and not jit then\n"
   "  return ffi.debug().cdata_mt\n"
   "else\n"
   "  return {}\n"
@@ -448,7 +466,7 @@ void luaT_registeratname(lua_State *L, const struct luaL_Reg *methods, const cha
     lua_rawget(L, idx);
   }
 
-  luaL_register(L, NULL, methods);
+  luaT_setfuncs(L, methods, 0);
   lua_pop(L, 1);
 }
 
@@ -494,9 +512,9 @@ int luaT_lua_newmetatable(lua_State *L)
   luaL_argcheck(L, lua_isnoneornil(L, 5) || lua_isfunction(L, 5), 5, "factory function or nil expected");
 
   if(is_in_module)
-    lua_getfield(L, LUA_GLOBALSINDEX, module_name);
+    lua_getglobal(L, module_name);
   else
-    lua_pushvalue(L, LUA_GLOBALSINDEX);
+    lua_pushglobaltable(L);
   if(!lua_istable(L, 6))
     luaL_error(L, "while creating metatable %s: bad argument #1 (%s is an invalid module name)", tname, module_name);
 
@@ -853,15 +871,17 @@ int luaT_lua_setenv(lua_State *L)
   if(!lua_isfunction(L, 1) && !lua_isuserdata(L, 1))
     luaL_typerror(L, 1, "function or userdata");
   luaL_checktype(L, 2, LUA_TTABLE);
-  lua_setfenv(L, 1);
+  lua_setuservalue(L, 1);
   return 0;
 }
 
 int luaT_lua_getenv(lua_State *L)
 {
   if(!lua_isfunction(L, 1) && !lua_isuserdata(L, 1))
     luaL_typerror(L, 1, "function or userdata");
-  lua_getfenv(L, 1);
+  lua_getuservalue(L, 1);
+  if (lua_isnil(L, -1))
+    lua_newtable(L);
   return 1;
 }
 

lib/luaT/luaT.h

@@ -32,13 +32,27 @@ extern "C" {
 # define LUAT_API LUA_EXTERNC
 #endif
 
+#if LUA_VERSION_NUM == 501
+# define lua_pushglobaltable(L) lua_pushvalue(L, LUA_GLOBALSINDEX)
+# define lua_setuservalue lua_setfenv
+# define lua_getuservalue lua_getfenv
+#else
+# define lua_objlen lua_rawlen
+static int luaL_typerror(lua_State *L, int narg, const char *tname)
+{
+  return luaL_error(L, "%s expected, got %s", tname, luaL_typename(L, narg));
+}
+#endif
+
 
 /* C functions */
 
 LUAT_API void* luaT_alloc(lua_State *L, long size);
 LUAT_API void* luaT_realloc(lua_State *L, void *ptr, long size);
 LUAT_API void luaT_free(lua_State *L, void *ptr);
 
+LUAT_API void luaT_setfuncs(lua_State *L, const luaL_Reg *l, int nup);
+
 LUAT_API const char* luaT_newmetatable(lua_State *L, const char *tname, const char *parenttname,
                                        lua_CFunction constructor, lua_CFunction destructor, lua_CFunction factory);
 

random.lua

@@ -46,7 +46,7 @@ void torch_random_init(lua_State *L)
   torch_Generator_init(L);
   torch_Generator_new(L);
   lua_setfield(L, -2, "_gen");
-  luaL_register(L, NULL, random__);
+  luaT_setfuncs(L, random__, 0);
 }
 ]])
 

test/test.lua

@@ -5,6 +5,10 @@ local torchtest = {}
 local msize = 100
 local precision
 
+-- Lua 5.2 compatibility
+local loadstring = loadstring or load
+local unpack = unpack or table.unpack
+
 local function maxdiff(x,y)
    local d = x-y
    if x:type() == 'torch.DoubleTensor' or x:type() == 'torch.FloatTensor' then

test/timeSort.lua

@@ -10,7 +10,8 @@ cmd:option('-r', 20, 'Number of repetitions')
 
 local options = cmd:parse(arg or {})
 function main()
-    local pow10 = torch.linspace(1,math.log10(options.N), options.p)
+    local log10 = math.log10 or function(x) return math.log(x, 10) end
+    local pow10 = torch.linspace(1,log10(options.N), options.p)
     local num_sizes = options.p
     local num_reps = options.r
 
@@ -128,11 +129,11 @@ function main()
     gnuplot.xlabel('N')
     gnuplot.ylabel('Speed-up Factor (s)')
     gnuplot.figprint('benchmarkRatio.png')
-    
+
     torch.save('benchmark.t7', {
                new_rnd=new_rnd,
                new_srt=new_srt,
-               new_cst=new_cst, 
+               new_cst=new_cst,
                old_rnd=old_rnd,
                old_srt=old_srt,
                old_cst=old_cst,

utils.c

@@ -113,7 +113,7 @@ static int torch_lua_getdefaulttensortype(lua_State *L)
 
 const char* torch_getdefaulttensortype(lua_State *L)
 {
-  lua_getfield(L, LUA_GLOBALSINDEX, "torch");
+  lua_getglobal(L, "torch");
   if(lua_istable(L, -1))
   {
     lua_getfield(L, -1, "Tensor");
@@ -214,5 +214,5 @@ static const struct luaL_Reg torch_utils__ [] = {
 
 void torch_utils_init(lua_State *L)
 {
-  luaL_register(L, NULL, torch_utils__);
+  luaT_setfuncs(L, torch_utils__, 0);
 }