On 09/25/2015 03:04 PM, Hans Hagen wrote:

On 9/25/2015 4:09 PM, Orion Poplawski wrote:

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I'm just starting to take a look how luatex makes use of lua. And it appears that luatex does not merely use lua, but extends it in various ways, essentially creating new lua dialect. Is the assessment correct? Is there any documentation on this?

Indeed we have some more on board. Keep in mind that lua is used as extension language so whenever it's used in an application there can be extensions.

Btw, a dialect implies a different language. Adding a couple of functions is not making it a dialect.

You appear to be extending it in at least four areas by adding new functions, and replacing some as described below. liolibext is the most "entangled" due to duplicating liolib code, lstrlibext also uses some Lua internals that are not normally exposed to consumers of Lua (e.g. lua_lock). I'm fine with not calling this a new "dialect", but it is certainly extended, though modifying popen()/read()/lines() is interesting. I'm interested to know if there has been any discussion with the Lua maintainers about incorporating any of these changes in Lua proper? liolibext.c: /* This extension only replaces one function: io.popen() and two metatable entries: f:read() and f:lines() but unfortunately it has to copy quite a bunch of lines from the original liolib.c to do so. */ llfslibext.c: adds to lfs: lua_setfield(L, -2, "isdir"); lua_pushcfunction(L, file_is_file); lua_setfield(L, -2, "isfile"); lua_pushcfunction(L, read_link); lua_setfield(L, -2, "readlink"); lua_pushcfunction(L, get_short_name); lua_setfield(L, -2, "shortname"); loslibext.c: lua_getglobal(L, "os"); lua_pushcfunction(L, ex_sleep); lua_setfield(L, -2, "sleep"); lua_pushliteral(L, OS_PLATTYPE); lua_setfield(L, -2, "type"); lua_pushliteral(L, OS_PLATNAME); lua_setfield(L, -2, "name"); lua_pushcfunction(L, ex_uname); lua_setfield(L, -2, "uname"); #if (! defined (_WIN32)) && (! defined (__SUNOS__)) lua_pushcfunction(L, os_times); lua_setfield(L, -2, "times"); #endif #if ! defined (__SUNOS__) lua_pushcfunction(L, os_gettimeofday); lua_setfield(L, -2, "gettimeofday"); #endif if (!safer) { lua_pushcfunction(L, os_setenv); lua_setfield(L, -2, "setenv"); lua_pushcfunction(L, os_exec); lua_setfield(L, -2, "exec"); lua_pushcfunction(L, os_spawn); lua_setfield(L, -2, "spawn"); lua_pushcfunction(L, os_execute); lua_setfield(L, -2, "execute"); lua_pushcfunction(L, os_tmpdir); lua_setfield(L, -2, "tmpdir"); } lstrlibext.c {"utfvalues", str_utfvalues}, {"utfcharacters", str_utfcharacters}, {"characters", str_characters}, {"characterpairs", str_characterpairs}, {"bytes", str_bytes}, {"bytepairs", str_bytepairs}, {"explode", str_split}, {"dump", str_dump},

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Also, is luajit used in the same way, or would it be possible to use a system installed luajit in building luatex?

The only benefit of luajit is the faster virtual machine. A downside is that there are some limitations in memory cq. stack usage. We use a patch that makes the string hashing faster (we use the normal lua method instead of the luajit one that is optimizied for urls and that can make luajit slower than lua).

Becaus eluatex uses lua as extension language it will always be shipped with a specific version (linked in or alongside the binary).

Hans

FWIW - Here are some changes I had to make while trying to compile against lua 5.3: diff --git a/texk/web2c/luatexdir/lua/liolibext.c b/texk/web2c/luatexdir/lua/liolibext.c index edf094d..883dce7 100644 --- a/texk/web2c/luatexdir/lua/liolibext.c +++ b/texk/web2c/luatexdir/lua/liolibext.c @@ -33,6 +33,7 @@ #include "lauxlib.h" #endif #include "lualib.h" +#include diff --git a/texk/web2c/luatexdir/lua/llualib.c b/texk/web2c/luatexdir/lua/llualib.c index 23bec6b..f0c4a21 100644 --- a/texk/web2c/luatexdir/lua/llualib.c +++ b/texk/web2c/luatexdir/lua/llualib.c @@ -258,7 +258,11 @@ static int set_bytecode(lua_State * L) lua_bytecode_registers[k].buf = xmalloc(LOAD_BUF_SIZE); lua_bytecode_registers[k].alloc = LOAD_BUF_SIZE; memset(lua_bytecode_registers[k].buf, 0, LOAD_BUF_SIZE); +#if LUA_VERSION_NUM >= 503 + lua_dump(L, writer, (void *) (lua_bytecode_registers + k),0); +#else lua_dump(L, writer, (void *) (lua_bytecode_registers + k)); +#endif } lua_pop(L, 1); return 0; diff --git a/texk/web2c/luatexdir/lua/texluac.w b/texk/web2c/luatexdir/lua/texluac.w index 396121c..e533b8f 100644 --- a/texk/web2c/luatexdir/lua/texluac.w +++ b/texk/web2c/luatexdir/lua/texluac.w @@ -265,7 +265,11 @@ int luac_main(int ac, char *av[]) static void PrintString(const TString* ts) { const char* s=getstr(ts); +#if LUA_VERSION_NUM >= 503 + size_t i,n=ts->len; +#else size_t i,n=ts->tsv.len; +#endif printf("%c",'"'); for (i=0; i= 503 PrintString(rawtsvalue(o)); +#else + PrintString(tsvalue(o)); +#endif break; default: /* cannot happen */ printf("? type=%d",ttype(o)); diff --git a/texk/web2c/luatexdir/slnunicode/slnunico.c b/texk/web2c/luatexdir/slnunicode/slnunico.c index 60ef95b..58e055e 100644 --- a/texk/web2c/luatexdir/slnunicode/slnunico.c +++ b/texk/web2c/luatexdir/slnunicode/slnunico.c @@ -435,7 +435,11 @@ static int str_dump (lua_State *L) { luaL_checktype(L, 1, LUA_TFUNCTION); lua_settop(L, 1); luaL_buffinit(L,&b); +#if LUA_VERSION_NUM >= 503 + if (lua_dump(L, writer, &b, 0) != 0) +#else if (lua_dump(L, writer, &b) != 0) +#endif luaL_error(L, "unable to dump given function"); luaL_pushresult(&b); return 1; -- Orion Poplawski Technical Manager 303-415-9701 x222 NWRA/CoRA Division FAX: 303-415-9702 3380 Mitchell Lane orion@cora.nwra.com Boulder, CO 80301 http://www.cora.nwra.com