/* ltexlib.c

   Copyright 2006-2012 Taco Hoekwater <taco@luatex.org>

   This file is part of LuaTeX.

   LuaTeX is free software; you can redistribute it and/or modify it under
   the terms of the GNU General Public License as published by the Free
   Software Foundation; either version 2 of the License, or (at your
   option) any later version.

   LuaTeX is distributed in the hope that it will be useful, but WITHOUT
   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
   License for more details.

   You should have received a copy of the GNU General Public License along
   with LuaTeX; if not, see <http://www.gnu.org/licenses/>. */

/* hh-ls: Because the lists start with a temp node, we have to set the prev link
to nil because otherwise at the lua end we expose temp which can create havoc. In the
setter no prev link is created so we can presume that it's not used later on. */

#include "ptexlib.h"
#include "lua/luatex-api.h"

/* tex random generators */
extern int unif_rand(int );
extern int norm_rand(void );
extern void init_randoms(int );

typedef struct {
    char *text;
    unsigned int tsize;
    void *next;
    boolean partial;
    int cattable;
    halfword tok;
    halfword nod;
} rope;

typedef struct {
    rope *head;
    rope *tail;
    char complete;              /* currently still writing ? */
} spindle;

#define  PARTIAL_LINE 1
#define  FULL_LINE    0

#define  write_spindle spindles[spindle_index]
#define  read_spindle  spindles[(spindle_index-1)]

static int spindle_size  = 0;
static spindle *spindles = NULL;
static int spindle_index = 0;

static int luac_store(lua_State * L, int i, int partial, int cattable)
{
    char *st = NULL;
    size_t tsize = 0;
    rope *rn = NULL;
    halfword tok = null;
    halfword nod = null;
    int t = lua_type(L, i);
    if (t == LUA_TNUMBER || t == LUA_TSTRING) {
        const char *sttemp;
        sttemp = lua_tolstring(L, i, &tsize);
        st = xmalloc((unsigned) (tsize + 1));
        memcpy(st, sttemp, (tsize + 1));
    } else if (t == LUA_TUSERDATA) {
        void *p ;
        p = lua_touserdata(L, i);
        if (p == NULL) {
            return 0;
        } else if (lua_getmetatable(L, i)) {
            lua_get_metatablelua(luatex_token);
            if (lua_rawequal(L, -1, -2)) {
                tok = (halfword) token_info((*((lua_token *)p)).token);
                lua_pop(L, 2);
            } else {
                lua_get_metatablelua(luatex_node);
                if (lua_rawequal(L, -1, -3)) {
                    nod = *((halfword *)p);
                    lua_pop(L, 3);
                } else {
                    lua_pop(L, 3);
                    return 0;
                }
            }
        } else {
            return 0;
        }
    } else {
        return 0;
    }
    /* common */
    luacstrings++;
    rn = (rope *) xmalloc(sizeof(rope));
    rn->text = st;
    rn->tsize = (unsigned) tsize;
    rn->tok = tok;
    rn->nod = nod;
    rn->next = NULL;
    rn->partial = partial;
    rn->cattable = cattable;
    /* add */
    if (write_spindle.head == NULL) {
        write_spindle.head = rn;
    } else {
        write_spindle.tail->next = rn;
    }
    write_spindle.tail = rn;
    write_spindle.complete = 0;
    return 1;
}

static int do_luacprint(lua_State * L, int partial, int deftable)
{
    int cattable = deftable;
    int startstrings = 1;
    int n = lua_gettop(L);
    if (cattable != NO_CAT_TABLE) {
        if (lua_type(L, 1) == LUA_TNUMBER && n > 1) {
            cattable = lua_tointeger(L, 1);
            startstrings = 2;
            if (cattable != -1 && cattable != -2 && !valid_catcode_table(cattable)) {
                cattable = DEFAULT_CAT_TABLE;
            }
        }
    }
    if (lua_type(L, startstrings) == LUA_TTABLE) {
        int i;
        for (i = 1;; i++) {
            lua_rawgeti(L, startstrings, i);
            if (luac_store(L, -1, partial, cattable)) {
                lua_pop(L, 1);
            } else {
                lua_pop(L, 1);
                break;
            }
        }
    } else {
        int i;
        for (i = startstrings; i <= n; i++) {
            luac_store(L, i, partial, cattable);
        }
    }
    return 0;
}

/* the next one writes a raw token (number) */

/*

int luatwrite(lua_State * L)
{
    int top = lua_gettop(L);
    if (top>0) {
        rope *rn = xmalloc(sizeof(rope)); // overkill
        int i = 1 ;
        luacstrings++; // should be luactokens
        rn->text = NULL;
        rn->tsize = 0;
        rn->partial = 0;
        rn->cattable = DEFAULT_CAT_TABLE;
        rn->next = NULL;
        rn->tok = 0;
        rn->nod = 0;
        if (write_spindle.head == NULL) {
            write_spindle.head = rn;
        } else {
            write_spindle.tail->next = rn;
        }
        write_spindle.tail = rn;
        write_spindle.complete = 0;
        while (1) {
            rn->tok = lua_tointeger(L,i);
            if (i<top) {
                rope *r = xmalloc(sizeof(rope)); // overkill
                r->text = NULL;
                r->tsize = 0;
                r->partial = 0;
                r->cattable = DEFAULT_CAT_TABLE;
                r->next = NULL;
                r->tok = 0;
                r->nod = 0;
                rn->next = r;
                rn = r;
                write_spindle.tail = rn;
                i++;
            } else {
                break;
            }
        }
    }
    return 0;
}

*/

/* the next one writes a raw node (number) */

/*

int luanwrite(lua_State * L)
{
    int top = lua_gettop(L);
    if (top>0) {
        rope *rn = xmalloc(sizeof(rope)); // overkill
        int i = 1 ;
        luacstrings++; // should be luactokens
        rn->text = NULL;
        rn->tsize = 0;
        rn->partial = 0;
        rn->cattable = DEFAULT_CAT_TABLE;
        rn->next = NULL;
        rn->tok = 0;
        rn->nod = 0;
        if (write_spindle.head == NULL) {
            write_spindle.head = rn;
        } else {
            write_spindle.tail->next = rn;
        }
        write_spindle.tail = rn;
        write_spindle.complete = 0;
        while (1) {
            rn->nod = lua_tointeger(L,i);
            if (i<top) {
                rope *r = xmalloc(sizeof(rope)); // overkill
                r->text = NULL;
                r->tsize = 0;
                r->partial = 0;
                r->cattable = DEFAULT_CAT_TABLE;
                r->next = NULL;
                r->tok = 0;
                r->nod = 0;
                rn->next = r;
                rn = r;
                write_spindle.tail = rn;
                i++;
            } else {
                break;
            }
        }
    }
    return 0;
}

*/

/* lua.write */

static int luacwrite(lua_State * L)
{
    return do_luacprint(L, FULL_LINE, NO_CAT_TABLE);
}

/* lua.print */

static int luacprint(lua_State * L)
{
    return do_luacprint(L, FULL_LINE, DEFAULT_CAT_TABLE);
}

/* lua.sprint */

static int luacsprint(lua_State * L)
{
    return do_luacprint(L, PARTIAL_LINE, DEFAULT_CAT_TABLE);
}

/* lua.cprint */

static int luaccprint(lua_State * L)
{
    /* so a negative value is a specific catcode with offset 1 */
    int cattable = lua_tointeger(L,1);
    if (cattable < 0 || cattable > 15) {
        cattable = - 12 - 0xFF ;
    } else {
        cattable = - cattable - 0xFF;
    }
    if (lua_type(L, 2) == LUA_TTABLE) {
        int i;
        for (i = 1;; i++) {
            lua_rawgeti(L, 2, i);
            if (luac_store(L, -1, PARTIAL_LINE, cattable)) {
                lua_pop(L, 1);
            } else {
                lua_pop(L, 1);
                break;
            }
        }
    } else {
        int i;
        int n = lua_gettop(L);
        for (i = 2; i <= n; i++) {
            luac_store(L, i, PARTIAL_LINE, cattable);
        }
    }
    return 0;
}

/* lua.tprint */

static int luactprint(lua_State * L)
{
    int i, j;
    int cattable, startstrings;
    int n = lua_gettop(L);
    for (i = 1; i <= n; i++) {
        cattable = DEFAULT_CAT_TABLE;
        startstrings = 1;
        if (lua_type(L, i) != LUA_TTABLE) {
            luaL_error(L, "no string to print");
        }
        lua_pushvalue(L, i); /* push the table */
        lua_pushinteger(L, 1);
        lua_gettable(L, -2);
        if (lua_type(L, -1) == LUA_TNUMBER) {
            cattable = lua_tointeger(L, -1);
            startstrings = 2;
            if (cattable != -1 && cattable != -2 && !valid_catcode_table(cattable)) {
                cattable = DEFAULT_CAT_TABLE;
            }
        }
        lua_pop(L, 1);
        for (j = startstrings;; j++) {
            lua_pushinteger(L, j);
            lua_gettable(L, -2);
            if (luac_store(L, -1, PARTIAL_LINE, cattable)) {
                lua_pop(L, 1);
            } else {
                lua_pop(L, 1);
                break;
            }
        }
        lua_pop(L, 1); /* pop the table */
    }
    return 0;
}

int luacstring_cattable(void)
{
    return (int) read_spindle.tail->cattable;
}

int luacstring_partial(void)
{
    return read_spindle.tail->partial;
}

int luacstring_final_line(void)
{
    return (read_spindle.tail->next == NULL);
}

int luacstring_input(halfword *n)
{
    rope *t = read_spindle.head;
    int ret = 1 ;
    if (!read_spindle.complete) {
        read_spindle.complete = 1;
        read_spindle.tail = NULL;
    }
    if (t == NULL) {
        if (read_spindle.tail != NULL)
            free(read_spindle.tail);
        read_spindle.tail = NULL;
        return 0;
    }
    if (t->text != NULL) {
        /* put that thing in the buffer */
        char *st = t->text;
        int ret = first;
        last = first;
        check_buffer_overflow(last + (int) t->tsize);
        while (t->tsize-- > 0)
            buffer[last++] = (packed_ASCII_code) * st++;
        if (!t->partial) {
            while (last - 1 > ret && buffer[last - 1] == ' ')
                last--;
        }
        free(t->text);
        t->text = NULL;
    } else if (t->tok > 0) {
        *n = t->tok;
        ret = 2;
    } else if (t->nod > 0) {
        *n = t->nod;
        ret = 3;
    }
    if (read_spindle.tail != NULL) {
        /* not a one-liner */
        free(read_spindle.tail);
    }
    read_spindle.tail = t;
    read_spindle.head = t->next;
    return ret;
}

/* open for reading, and make a new one for writing */

void luacstring_start(int n)
{
    (void) n; /* for -W */
    spindle_index++;
    if (spindle_size == spindle_index) {
        /* add a new one */
        spindles = xrealloc(spindles, (unsigned) (sizeof(spindle) * (unsigned) (spindle_size + 1)));
        spindles[spindle_index].head = NULL;
        spindles[spindle_index].tail = NULL;
        spindles[spindle_index].complete = 0;
        spindle_size++;
    }
}

/* close for reading */

void luacstring_close(int n)
{
    rope *next, *t;
    (void) n; /* for -W */
    next = read_spindle.head;
    while (next != NULL) {
        if (next->text != NULL)
            free(next->text);
        t = next;
        next = next->next;
        if (t==read_spindle.tail) {
            read_spindle.tail = NULL;
        }
        free(t);
    }
    read_spindle.head = NULL;
    if (read_spindle.tail != NULL)
        free(read_spindle.tail);
    read_spindle.tail = NULL;
    read_spindle.complete = 0;
    spindle_index--;
}

/* local (static) versions */

#define check_index_range(j,s) \
  if (j<0 || j > 65535) { \
    luaL_error(L, "incorrect index specification for tex.%s()", s);  }

#define check_register(base) do { \
    int k = get_item_index(L, lua_gettop(L), base); \
    if ((k>=0) && (k <= 65535)) { \
        lua_pushinteger(L,k); \
    } else { \
        lua_pushboolean(L,false); \
    } \
    return 1; \
} while (1)

static const char *scan_integer_part(lua_State * L, const char *ss, int *ret, int *radix_ret)
{
    boolean negative = false; /* should the answer be negated? */
    int m = 214748364;        /* |$2^{31}$ / radix|, the threshold of danger */
    int d;                    /* the digit just scanned */
    boolean vacuous = true;   /* have no digits appeared? */
    boolean OK_so_far = true; /* has an error message been issued? */
    int radix1 = 10;          /* the radix of the integer */
    int c = 0;                /* the current character */
    const char *s;            /* where we stopped in the string |ss| */
    integer val = 0;          /* return value */
    s = ss;
    do {
        do {
            c = *s++;
        } while (c && c == ' ');
        if (c == '-') {
            negative = !negative;
            c = '+';
        }
    } while (c == '+');
    if (c == '\'') {
        radix1 = 8;
        m = 02000000000;
        c = *s++;
    } else if (c == '"') {
        radix1 = 16;
        m = 01000000000;
        c = *s++;
    }
    /* Accumulate the constant until |cur_tok| is not a suitable digit */
    while (1) {
        if ((c < '0' + radix1) && (c >= '0') && (c <= '0' + 9)) {
            d = c - '0';
        } else if (radix1 == 16) {
            if ((c <= 'A' + 5) && (c >= 'A')) {
                d = c - 'A' + 10;
            } else if ((c <= 'a' + 5) && (c >= 'a')) {
                d = c - 'a' + 10;
            } else {
                break;
            }
        } else {
            break;
        }
        vacuous = false;
        if ((val >= m) && ((val > m) || (d > 7) || (radix1 != 10))) {
            if (OK_so_far) {
                luaL_error(L, "Number too big");
                val = infinity;
                OK_so_far = false;
            }
        } else {
            val = val * radix1 + d;
        }
        c = *s++;
    }
    if (vacuous) {
        /* Express astonishment that no number was here */
        luaL_error(L, "Missing number, treated as zero");
    }
    if (negative)
        val = -val;
    *ret = val;
    *radix_ret = radix1;
    if (c != ' ' && s > ss)
        s--;
    return s;
}

#define set_conversion(A,B) do { num=(A); denom=(B); } while(0)

/* sets |cur_val| to a dimension */

static const char *scan_dimen_part(lua_State * L, const char *ss, int *ret)
{
    boolean negative = false;   /* should the answer be negated? */
    int f = 0;                  /* numerator of a fraction whose denominator is $2^{16}$ */
    int num, denom;             /* conversion ratio for the scanned units */
    int k;                      /* number of digits in a decimal fraction */
    scaled v;                   /* an internal dimension */
    int save_cur_val;           /* temporary storage of |cur_val| */
    int c;                      /* the current character */
    const char *s = ss;         /* where we are in the string */
    int radix1 = 0;             /* the current radix */
    int rdig[18];               /* to save the |dig[]| array */
    int saved_tex_remainder;    /* to save |tex_remainder|  */
    int saved_arith_error;      /* to save |arith_error|  */
    int saved_cur_val;          /* to save the global |cur_val| */
    saved_tex_remainder = tex_remainder;
    saved_arith_error = arith_error;
    saved_cur_val = cur_val;
    /* get the next non-blank non-sign */
    do {
        /* get the next non-blank non-call token */
        do {
            c = *s++;
        } while (c && c == ' ');
        if (c == '-') {
            negative = !negative;
            c = '+';
        }
    } while (c == '+');
    if (c == ',') {
        c = '.';
    }
    if (c != '.') {
        s = scan_integer_part(L, (s > ss ? (s - 1) : ss), &cur_val, &radix1);
        c = *s;
    } else {
        radix1 = 10;
        cur_val = 0;
        c = *(--s);
    }
    if (c == ',')
        c = '.';
    if ((radix1 == 10) && (c == '.')) {
        /* scan decimal fraction */
        for (k = 0; k < 18; k++)
            rdig[k] = dig[k];
        k = 0;
        s++;
        /* get rid of the '.' */
        while (1) {
            c = *s++;
            if ((c > '0' + 9) || (c < '0'))
                break;
            if (k < 17) {
                /* digits for |k>=17| cannot affect the result */
                dig[k++] = c - '0';
            }
        }
        f = round_decimals(k);
        if (c != ' ')
            c = *(--s);
        for (k = 0; k < 18; k++)
            dig[k] = rdig[k];
    }
    if (cur_val < 0) {          /* in this case |f=0| */
        negative = !negative;
        cur_val = -cur_val;
    }
    /*
        Scan for (u)units that are internal dimensions; |goto attach_sign| with
        |cur_val| set if found.
    */
    save_cur_val = cur_val;
    /* Get the next non-blank non-call... */
    do {
        c = *s++;
    } while (c && c == ' ');
    if (c != ' ')
        c = *(--s);
    if (strncmp(s, "em", 2) == 0) {
        s += 2;
        v = (quad(get_cur_font()));
    } else if (strncmp(s, "ex", 2) == 0) {
        s += 2;
        v = (x_height(get_cur_font()));
    } else if (strncmp(s, "px", 2) == 0) {
        s += 2;
        v = px_dimen_par;
    } else {
        goto NOT_FOUND;
    }
    c = *s++;
    if (c != ' ') {
        c = *(--s);
    }
    cur_val = nx_plus_y(save_cur_val, v, xn_over_d(v, f, 0200000));
    goto ATTACH_SIGN;
  NOT_FOUND:
    /* Scan for (m)\.{mu} units and |goto attach_fraction| */
    if (strncmp(s, "mu", 2) == 0) {
        s += 2;
        goto ATTACH_FRACTION;
    }
    if (strncmp(s, "true", 4) == 0) {
        /* Adjust (f)for the magnification ratio */
        s += 4;
        if (output_mode_used <= OMODE_DVI) {
            prepare_mag();
            if (mag_par != 1000) {
                cur_val = xn_over_d(cur_val, 1000, mag_par);
                f = (1000 * f + 0200000 * tex_remainder) / mag_par;
                cur_val = cur_val + (f / 0200000);
                f = f % 0200000;
            }
        }
        do {
            c = *s++;
        } while (c && c == ' ');
        c = *(--s);
    }
    if (strncmp(s, "pt", 2) == 0) {
        s += 2;
        goto ATTACH_FRACTION;   /* the easy case */
    }
    /*
        Scan for (a)all other units and adjust |cur_val| and |f| accordingly; |goto done|
        in the case of scaled points
    */
    if (strncmp(s, "mm", 2) == 0) {
        s += 2;
        set_conversion(7227, 2540);
    } else if (strncmp(s, "cm", 2) == 0) {
        s += 2;
        set_conversion(7227, 254);
    } else if (strncmp(s, "sp", 2) == 0) {
        s += 2;
        goto DONE;
    } else if (strncmp(s, "bp", 2) == 0) {
        s += 2;
        set_conversion(7227, 7200);
    } else if (strncmp(s, "in", 2) == 0) {
        s += 2;
        set_conversion(7227, 100);
    } else if (strncmp(s, "dd", 2) == 0) {
        s += 2;
        set_conversion(1238, 1157);
    } else if (strncmp(s, "cc", 2) == 0) {
        s += 2;
        set_conversion(14856, 1157);
    } else if (strncmp(s, "pc", 2) == 0) {
        s += 2;
        set_conversion(12, 1);
    } else if (strncmp(s, "nd", 2) == 0) {
        s += 2;
        set_conversion(685, 642);
    } else if (strncmp(s, "nc", 2) == 0) {
        s += 2;
        set_conversion(1370, 107);
    } else {
        /* Complain about unknown unit and |goto done2| */
        luaL_error(L, "Illegal unit of measure (pt inserted)");
        goto DONE2;
    }
    cur_val = xn_over_d(cur_val, num, denom);
    f = (num * f + 0200000 * tex_remainder) / denom;
    cur_val = cur_val + (f / 0200000);
    f = f % 0200000;
  DONE2:
  ATTACH_FRACTION:
    if (cur_val >= 040000)
        arith_error = true;
    else
        cur_val = cur_val * 65536 + f;
  DONE:
    /* Scan an optional space */
    c = *s++;
    if (c != ' ')
        s--;
  ATTACH_SIGN:
    if (arith_error || (abs(cur_val) >= 010000000000)) {
        /* Report that this dimension is out of range */
        luaL_error(L, "Dimension too large");
        cur_val = max_dimen;
    }
    if (negative)
        cur_val = -cur_val;
    *ret = cur_val;
    tex_remainder = saved_tex_remainder;
    arith_error = saved_arith_error;
    cur_val = saved_cur_val;
    return s;
}

int dimen_to_number(lua_State * L, const char *s)
{
    int j = 0;
    const char *d = scan_dimen_part(L, s, &j);
    if (*d) {
        luaL_error(L, "conversion failed (trailing junk?)");
        j = 0;
    }
    return j;
}

static int tex_scaledimen(lua_State * L)
{
    int sp;
    int t = lua_type(L, 1);
    if (t == LUA_TNUMBER) {
        sp = lua_roundnumber(L, 1);
    } else if (t == LUA_TSTRING) {
        sp = dimen_to_number(L, lua_tostring(L, 1));
    } else {
        luaL_error(L, "argument must be a string or a number");
        return 0;
    }
    lua_pushinteger(L, sp);
    return 1;
}

static int texerror (lua_State * L)
{
    const char **errhlp = NULL;
    const char *error = luaL_checkstring(L,1);
    int n = lua_gettop(L);
    if (n==2 && lua_type(L, n) == LUA_TTABLE) {
        int i;
        int l = 1; /* |errhlp| is terminated by a NULL entry */
        for (i = 1;; i++) {
            lua_rawgeti(L, n, i);
            if (lua_type(L,-1) == LUA_TSTRING) {
                l++;
                lua_pop(L, 1);
            } else {
                lua_pop(L, 1);
                break;
            }
        }
        if (l>1) {
          errhlp = xmalloc(l * sizeof(char *));
          memset(errhlp,0,l * sizeof(char *));
          for (i = 1;; i++) {
            lua_rawgeti(L, n, i);
            if (lua_type(L,-1) == LUA_TSTRING) {
                errhlp[(i-1)] = lua_tostring(L,-1);
                lua_pop(L, 1);
            } else {
                break;
            }
	  }
	}
    }
    deletions_allowed = false;
    tex_error(error, errhlp);
    if (errhlp)
      xfree(errhlp);
    deletions_allowed = true;
    return 0;
}

static int get_item_index(lua_State * L, int i, int base)
{
    size_t kk;
    int k;
    int cur_cs1;
    const char *s;
    switch (lua_type(L, i)) {
        case LUA_TSTRING:
            s = lua_tolstring(L, i, &kk);
            cur_cs1 = string_lookup(s, kk);
            if (cur_cs1 == undefined_control_sequence || cur_cs1 == undefined_cs_cmd)
                k = -1; /* guarandeed invalid */
            else
                k = (equiv(cur_cs1) - base);
            break;
        case LUA_TNUMBER:
            k = luaL_checkinteger(L, i);
            break;
        default:
            luaL_error(L, "argument must be a string or a number");
            k = -1; /* not a valid index */
    }
    return k;
}

#define check_item_global(L,top,isglobal) \
    if (top == 3 && (lua_type(L,1) == LUA_TSTRING)) { \
        const char *s = lua_tostring(L, 1); \
        if (lua_key_eq(s,global)) { \
            isglobal = 1; \
        } \
    }

#define set_item_index_plus(L, where, base, what, value, is_global, is_assign, set_register, glue) { \
    size_t len;                                                                       \
    const char *str;                                                                  \
    int key, err, cs;                                                                 \
    int save_global_defs = global_defs_par;                                           \
    if (is_global) {                                                                  \
        global_defs_par = 1;                                                          \
    }                                                                                 \
    switch (lua_type(L, where)) {                                                     \
        case LUA_TSTRING:                                                             \
            str = lua_tolstring(L, where, &len);                                      \
            cs = string_lookup(str, len);                                             \
            if (cs == undefined_control_sequence || cs == undefined_cs_cmd) {         \
                luaL_error(L, "incorrect %s name", what);                             \
            } else {                                                                  \
                key = equiv(cs) - base;                                               \
                if (key >= 0 && key <= 65535) {                                       \
                    err = set_register(key, value);                                   \
                    if (err) {                                                        \
                        luaL_error(L, "incorrect %s value", what);                    \
                    }                                                                 \
                } else if (is_assign(eq_type(cs))) {                                  \
                    if (glue) {                                                       \
                        int a = is_global;                                            \
                        define(equiv(cs), assign_glue_cmd, value);                    \
                    } else {                                                          \
                        assign_internal_value((is_global ? 4 : 0), equiv(cs), value); \
                    }                                                                 \
                } else {                                                              \
                    luaL_error(L, "incorrect %s name", what);                         \
                }                                                                     \
            }                                                                         \
            break;                                                                    \
        case LUA_TNUMBER:                                                             \
            key = luaL_checkinteger(L, where);                                        \
            if (key>=0 && key <= 65535) {                                             \
                err = set_register(key, value);                                       \
                if (err) {                                                            \
                    luaL_error(L, "incorrect %s value", what);                        \
                }                                                                     \
            } else {                                                                  \
                luaL_error(L, "incorrect %s index", what);                            \
            }                                                                         \
            break;                                                                    \
        default:                                                                      \
            luaL_error(L, "argument of 'set%s' must be a string or a number", what);  \
    }                                                                                 \
    global_defs_par = save_global_defs;                                               \
}

static int gettex(lua_State * L);

#define get_item_index_plus(L, where, base, what, value, is_assign, get_register, texget) { \
    size_t len;                                                                       \
    const char *str;                                                                  \
    int key, cs;                                                                      \
    switch (lua_type(L, where)) {                                                     \
        case LUA_TSTRING:                                                             \
            str = lua_tolstring(L, where, &len);                                      \
            cs = string_lookup(str, len);                                             \
            if (cs == undefined_control_sequence || cs == undefined_cs_cmd) {         \
                luaL_error(L, "incorrect %s name", what);                             \
            } else {                                                                  \
                key = equiv(cs) - base;                                               \
                if (key >= 0 && key <= 65535) {                                       \
                    value = get_register(key);                                        \
                } else if (is_assign(eq_type(cs))) {                                  \
                    texget = gettex(L); /* lazy */                                    \
                } else {                                                              \
                    luaL_error(L, "incorrect %s name", what);                         \
                }                                                                     \
            }                                                                         \
            break;                                                                    \
        case LUA_TNUMBER:                                                             \
            key = luaL_checkinteger(L, where);                                        \
            if (key>=0 && key <= 65535) {                                             \
                value = get_register(key);                                            \
            } else {                                                                  \
                luaL_error(L, "incorrect %s index", what);                            \
            }                                                                         \
            break;                                                                    \
        default:                                                                      \
            luaL_error(L, "argument of 'get%s' must be a string or a number", what);  \
    }                                                                                 \
}

static int isdimen(lua_State * L)
{
    check_register(scaled_base);
}

static int setdimen(lua_State * L)
{
    int isglobal = 0;
    int value = 0;
    int top = lua_gettop(L);
    int t = lua_type(L, top);
    check_item_global(L,top,isglobal);
    if (t == LUA_TNUMBER) {
        value = lua_roundnumber(L, top);
    } else if (t == LUA_TSTRING) {
        value = dimen_to_number(L, lua_tostring(L, top));
    } else {
        luaL_error(L, "unsupported %s value type","dimen");
    }
    set_item_index_plus(L, top-1, scaled_base, "dimen", value, isglobal, is_dim_assign, set_tex_dimen_register, false);
    return 0;
}

static int getdimen(lua_State * L)
{
    int value = 0;
    int texget = 0;
    get_item_index_plus(L, lua_gettop(L), scaled_base, "dimen", value, is_dim_assign, get_tex_dimen_register, texget);
    if (texget > 0) {
        return texget;
    }
    lua_pushinteger(L, value);
    return 1;
}

static int isskip(lua_State * L)
{
    check_register(skip_base);
}

static int setskip(lua_State * L)
{
    int isglobal = 0;
    halfword *value = NULL;
    int top = lua_gettop(L);
    check_item_global(L,top,isglobal);
    value = check_isnode(L, top);
    if (type(*value) == glue_spec_node) {
        set_item_index_plus(L, top-1, skip_base, "skip", *value, isglobal, is_glue_assign, set_tex_skip_register, true);
    } else {
        luaL_error(L, "glue_spec expected");
    }
    return 0;
}

static int getskip(lua_State * L)
{
    int value = 0;
    int texget = 0;
    get_item_index_plus(L, lua_gettop(L), skip_base, "skip", value, is_glue_assign, get_tex_skip_register, texget);
    if (texget > 0) {
        return texget;
    }
    if (value == null) {
        lua_nodelib_push_fast(L, copy_node(zero_glue));
    } else {
        lua_nodelib_push_fast(L, copy_node(value));
    }
    return 1;
}

static int setglue(lua_State * L)
{
    int isglobal = 0;
    int index = 1;
    halfword value = copy_node(zero_glue);
    int top = lua_gettop(L);
    check_item_global(L,top,isglobal);
    if (isglobal) {
        index = 2;
        top -= 1;
    }
    /* [global] slot [width] [stretch] [shrink] [stretch_order] [shrink_order] */
    if (top > 1) { width(value) = lua_roundnumber(L,index+1); }
    if (top > 2) { stretch(value) = lua_roundnumber(L,index+2); }
    if (top > 3) { shrink(value) = lua_roundnumber(L,index+3); }
    if (top > 4) { stretch_order(value) = lua_tointeger(L,index+4); }
    if (top > 5) { shrink_order(value) = lua_tointeger(L,index+5); }
    set_item_index_plus(L, index, skip_base, "skip", value, isglobal, is_glue_assign, set_tex_skip_register, true);
    return 0;
}

static int getglue(lua_State * L)
{
    int value = 0;
    int texget = 0;
    int top = lua_gettop(L);
    int dim = -1;
    if (top > 1 && lua_type(L,top) == LUA_TBOOLEAN) {
        dim = lua_toboolean(L,top);
        top = top - 1;
    } else {
        lua_pushboolean(L,1);
        dim = 1 ;
        /* no top adaption. somewhat messy, but the gettex fallback checks itself */
    }
    /* checks itself for the boolean */
    get_item_index_plus(L, top, skip_base, "glue", value, is_glue_assign, get_tex_skip_register, texget);
    if (texget > 0) {
        return texget;
    }
    if (dim == 0) {
        /* false */
        if (value == null) {
            lua_pushinteger(L,0);
        } else {
            lua_pushinteger(L,width(value));
        }
        return 1;
   } else {
        /* true and nil */
        if (value == null) {
            lua_pushinteger(L,0);
            lua_pushinteger(L,0);
            lua_pushinteger(L,0);
            lua_pushinteger(L,0);
            lua_pushinteger(L,0);
        } else {
            lua_pushinteger(L,width(value));
            lua_pushinteger(L,stretch(value));
            lua_pushinteger(L,shrink(value));
            lua_pushinteger(L,stretch_order(value));
            lua_pushinteger(L,shrink_order(value));
        }
        return 5;
    }
}

static int ismuskip(lua_State * L)
{
    check_register(mu_skip_base);
}

static int setmuskip(lua_State * L)
{
    int isglobal = 0;
    halfword *value = NULL;
    int top = lua_gettop(L);
    check_item_global(L,top,isglobal);
    value = check_isnode(L, top);
    set_item_index_plus(L, top-1, mu_skip_base, "muskip", *value, isglobal, is_mu_glue_assign, set_tex_mu_skip_register, true);
    return 0;
}

static int getmuskip(lua_State * L)
{
    int value = 0;
    int texget = 0;
    get_item_index_plus(L, lua_gettop(L), mu_skip_base, "muskip", value, is_mu_glue_assign, get_tex_mu_skip_register, texget);
    if (texget > 0) {
        return texget;
    }
    lua_nodelib_push_fast(L, copy_node(value));
    return 1;
}

static int setmuglue(lua_State * L)
{
    int isglobal = 0;
    int index = 1;
    halfword value = copy_node(zero_glue);
    int top = lua_gettop(L);
    check_item_global(L,top,isglobal);
    if (isglobal) {
        index = 2;
        top -= 1;
    }
    /* [global] slot [width] [stretch] [shrink] [stretch_order] [shrink_order] */
    if (top > 1) { width(value) = lua_roundnumber(L,index+1); }
    if (top > 2) { stretch(value) = lua_roundnumber(L,index+2); }
    if (top > 3) { shrink(value) = lua_roundnumber(L,index+3); }
    if (top > 4) { stretch_order(value) = lua_tointeger(L,index+4); }
    if (top > 5) { shrink_order(value) = lua_tointeger(L,index+5); }
    set_item_index_plus(L, index, mu_skip_base, "muskip", value, isglobal, is_mu_glue_assign, set_tex_mu_skip_register, true);
    return 0;
}

static int getmuglue(lua_State * L)
{
    int value = 0;
    int texget = 0;
    int top = lua_gettop(L);
    int dim = -1;
    if (top > 1 && lua_type(L,top) == LUA_TBOOLEAN) {
        dim = lua_toboolean(L,top);
        top = top - 1;
    } else {
        lua_pushboolean(L,1);
        dim = 1 ;
        /* no top adaption. somewhat messy, but the gettex fallback checks itself */
    }
    /* checks itself for the boolean */
    get_item_index_plus(L, top, mu_skip_base, "muskip", value, is_mu_glue_assign, get_tex_mu_skip_register, texget);
    if (texget > 0) {
        return texget;
    }
    if (dim == 0) {
        /* false */
        if (value == null) {
            lua_pushinteger(L,0);
        } else {
            lua_pushinteger(L,width(value));
        }
        return 1;
   } else {
        /* true and nil */
        if (value == null) {
            lua_pushinteger(L,0);
            lua_pushinteger(L,0);
            lua_pushinteger(L,0);
            lua_pushinteger(L,0);
            lua_pushinteger(L,0);
        } else {
            lua_pushinteger(L,width(value));
            lua_pushinteger(L,stretch(value));
            lua_pushinteger(L,shrink(value));
            lua_pushinteger(L,stretch_order(value));
            lua_pushinteger(L,shrink_order(value));
        }
        return 5;
    }
}

static int iscount(lua_State * L)
{
    check_register(count_base);
}

static int setcount(lua_State * L)
{
    int t;
    int isglobal = 0;
    int value = 0;
    int top = lua_gettop(L);
    check_item_global(L,top,isglobal);
    t = lua_type(L,top);
    if (t == LUA_TNUMBER) {
        value = lua_tointeger(L, top);
    } else {
        luaL_error(L, "unsupported %s value type","count");
    }
    set_item_index_plus(L, top-1, count_base, "count", value, isglobal, is_int_assign, set_tex_count_register, false);
    return 0;
}

static int getcount(lua_State * L)
{
    int value = 0;
    int texget = 0;
    get_item_index_plus(L, lua_gettop(L), count_base, "count", value, is_int_assign, get_tex_count_register, texget);
    if (texget > 0) {
        return texget;
    }
    lua_pushinteger(L, value);
    return 1;
}

static int isattribute(lua_State * L)
{
    check_register(attribute_base);
}

/* there are no system set attributes so this is a bit overkill */

static int setattribute(lua_State * L)
{
    int t;
    int isglobal = 0;
    int value = 0;
    int top = lua_gettop(L);
    check_item_global(L,top,isglobal);
    t = lua_type(L,top);
    if (t == LUA_TNUMBER) {
        value = lua_tointeger(L, top);
    } else {
        luaL_error(L, "unsupported %s value type","attribute");
    }
    set_item_index_plus(L, top-1, attribute_base, "attribute", value, isglobal, is_attr_assign, set_tex_attribute_register, false);
    return 0;
}

static int getattribute(lua_State * L)
{
    int value = 0;
    int texget = 0;
    get_item_index_plus(L, lua_gettop(L), attribute_base, "attribute", value, is_attr_assign, get_tex_attribute_register, texget);
    if (texget > 0) {
        return texget;
    }
    lua_pushinteger(L, value);
    return 1;
}

/* todo: we can avoid memcpy as there is no need to go through the pool */

/* use string_to_toks */

static int istoks(lua_State * L)
{
    check_register(toks_base);
}

static int settoks(lua_State * L)
{
    int i, err, k;
    lstring str;
    char *s;
    const char *ss;
    int is_global = 0;
    int save_global_defs = global_defs_par;
    int n = lua_gettop(L);
    if (n == 3 && (lua_type(L,1) == LUA_TSTRING)) {
        const char *s = lua_tostring(L, 1);
        if (lua_key_eq(s,global))
            is_global = 1;
    }
    if (is_global)
        global_defs_par = 1;
    i = lua_gettop(L);
    if (lua_type(L,i) != LUA_TSTRING) {
        luaL_error(L, "unsupported value type");
    }
    ss = lua_tolstring(L, i, &str.l);
    s = xmalloc (str.l+1);
    memcpy (s, ss, str.l+1);
    str.s = (unsigned char *)s;
    k = get_item_index(L, (i - 1), toks_base);
    check_index_range(k, "settoks");
    err = set_tex_toks_register(k, str);
    xfree(str.s);
    global_defs_par = save_global_defs;
    if (err) {
        luaL_error(L, "incorrect value");
    }
    return 0;
}

static int scantoks(lua_State * L)
{
    int i, err, k, c;
    lstring str;
    char *s;
    const char *ss;
    int is_global = 0;
    int save_global_defs = global_defs_par;
    int n = lua_gettop(L);
    if (n == 4 && (lua_type(L,1) == LUA_TSTRING)) {
        const char *s = lua_tostring(L, 1);
        if (lua_key_eq(s,global))
            is_global = 1;
    }
    /* action : vsettokscct(L, is_global); */
    if (is_global)
        global_defs_par = 1;
    i = lua_gettop(L);
    if (lua_type(L,i) != LUA_TSTRING) {
        luaL_error(L, "unsupported value type");
    }
    ss = lua_tolstring(L, i, &str.l);
    s = xmalloc (str.l+1);
    memcpy (s, ss, str.l+1);
    str.s = (unsigned char *)s;
    k = get_item_index(L, (i - 2), toks_base);
    c = luaL_checkinteger(L, i - 1);
    check_index_range(k, "settoks");
    err = scan_tex_toks_register(k, c, str);
    xfree(str.s);
    global_defs_par = save_global_defs;
    if (err) {
        luaL_error(L, "incorrect value");
    }
    return 0;
}

static int gettoks(lua_State * L)
{
    char *ss;
    str_number t;
    int k = get_item_index(L, lua_gettop(L), toks_base);
    check_index_range(k, "gettoks");
    t = get_tex_toks_register(k);
    ss = makecstring(t);
    lua_pushstring(L, ss);
    free(ss);
    flush_str(t);
    return 1;
}

static int get_box_id(lua_State * L, int i, boolean report)
{
    const char *s;
    int cur_cs1, cur_cmd1;
    size_t k = 0;
    int j = -1;
    switch (lua_type(L, i)) {
        case LUA_TSTRING:
            s = lua_tolstring(L, i, &k);
            cur_cs1 = string_lookup(s, k);
            cur_cmd1 = eq_type(cur_cs1);
            if (cur_cmd1 == char_given_cmd ||
                cur_cmd1 == math_given_cmd) {
                j = equiv(cur_cs1);
            }
            break;
        case LUA_TNUMBER:
            j = lua_tointeger(L, (i));
            break;
        default:
            if (report) {
                luaL_error(L, "argument must be a string or a number");
            }
            j = -1;                 /* not a valid box id */
    }
    return j;
}

static int getbox(lua_State * L)
{
    int t;
    int k = get_box_id(L, -1, true);
    check_index_range(k, "getbox");
    t = get_tex_box_register(k);
    nodelist_to_lua(L, t);
    return 1;
}

static int splitbox(lua_State * L)
{
    const char *s;
    int k = get_box_id(L, 1, true);
    check_index_range(k, "splitbox");
    if (lua_isnumber(L, 2)) {
        int m = 1;
        if (lua_type(L, 3) == LUA_TSTRING) {
            s = lua_tostring(L, 3);
            if (lua_key_eq(s, exactly)) {
                m = 0;
            } else if (lua_key_eq(s, additional)) {
                m = 1;
            }
        } else if (lua_type(L, 3) == LUA_TNUMBER) {
            m = (int) lua_tointeger(L, 3);
        }
        if ((m<0) || (m>1)) {
            luaL_error(L, "wrong mode in splitbox");
        }
        nodelist_to_lua(L, vsplit(k,lua_roundnumber(L,2),m));
    } else {
        /* maybe a warning */
        lua_pushnil(L);
    }
    return 1;
}

static int isbox(lua_State * L)
{
    int k = get_box_id(L, -1, false);
    lua_pushboolean(L,(k>=0 && k<=65535));
    return 1;
}

static int vsetbox(lua_State * L, int is_global)
{
    int j, k, err, t;
    int save_global_defs;
    k = get_box_id(L, -2, true);
    check_index_range(k, "setbox");
    t = lua_type(L, -1);
    if (t == LUA_TBOOLEAN) {
        j = lua_toboolean(L, -1);
        if (j == 0) {
            j = null;
        } else {
            return 0;
        }
    } else if (t == LUA_TNIL) {
        j = null;
    } else {
        j = nodelist_from_lua(L,-1);
        if (j != null && type(j) != hlist_node && type(j) != vlist_node) {
            luaL_error(L, "setbox: incompatible node type (%s)\n", get_node_name(type(j), subtype(j)));
            return 0;
        }
    }
    save_global_defs = global_defs_par;
    if (is_global) {
        global_defs_par = 1;
    }
    err = set_tex_box_register(k, j);
    global_defs_par = save_global_defs;
    if (err) {
        luaL_error(L, "incorrect value");
    }
    return 0;
}

static int setbox(lua_State * L)
{
    int isglobal = 0;
    int n = lua_gettop(L);
    if (n == 3 && (lua_type(L,1) == LUA_TSTRING)) {
        const char *s = lua_tostring(L, 1);
        if (lua_key_eq(s,global))
            isglobal = 1;
    }
    return vsetbox(L, isglobal);
}

#define check_char_range(j,s,lim) \
    if (j<0 || j >= lim) { \
        luaL_error(L, "incorrect character value %d for tex.%s()", (int) j, s); \
    }

static int setcode (lua_State *L, void (*setone)(int,halfword,quarterword),
            void (*settwo)(int,halfword,quarterword), const char *name, int lim)
{
    int ch;
    halfword val, ucval;
    int level = cur_level;
    int n = lua_gettop(L);
    int f = 1;
    if (n>1 && lua_type(L,1) == LUA_TTABLE)
        f++;
    if (n>2 && (lua_type(L,f) == LUA_TSTRING)) {
        const char *s = lua_tostring(L, f);
        if (lua_key_eq(s,global)) {
            level = level_one;
            f++;
        }
    }
    ch = luaL_checkinteger(L, f);
    check_char_range(ch, name, 65536*17);
    val = (halfword) luaL_checkinteger(L, f+1);
    check_char_range(val, name, lim);
    (setone)(ch, val, level);
    if (settwo != NULL && n-f == 2) {
        ucval = (halfword) luaL_checkinteger(L, f+2);
        check_char_range(ucval, name, lim);
        (settwo)(ch, ucval, level);
    }
    return 0;
}

static int setlccode(lua_State * L)
{
    return setcode(L, &set_lc_code, &set_uc_code, "setlccode",  65536*17);
}

static int getlccode(lua_State * L)
{
    int ch = luaL_checkinteger(L, -1);
    check_char_range(ch, "getlccode", 65536*17);
    lua_pushinteger(L, get_lc_code(ch));
    return 1;
}

static int setuccode(lua_State * L)
{
    return setcode(L, &set_uc_code, &set_lc_code, "setuccode", 65536*17);
}

static int getuccode(lua_State * L)
{
    int ch = luaL_checkinteger(L, -1);
    check_char_range(ch, "getuccode",  65536*17);
    lua_pushinteger(L, get_uc_code(ch));
    return 1;
}

static int setsfcode(lua_State * L)
{
    return setcode(L, &set_sf_code, NULL, "setsfcode", 32768);
}

static int getsfcode(lua_State * L)
{
    int ch = luaL_checkinteger(L, -1);
    check_char_range(ch, "getsfcode",  65536*17);
    lua_pushinteger(L, get_sf_code(ch));
    return 1;
}

static int setcatcode(lua_State * L)
{
    int ch;
    halfword val;
    int level = cur_level;
    int cattable = cat_code_table_par;
    int n = lua_gettop(L);
    int f = 1;
    if (n>1 && lua_type(L,1) == LUA_TTABLE)
        f++;
    if (n>2 && (lua_type(L,f) == LUA_TSTRING)) {
        const char *s = lua_tostring(L, f);
        if (lua_key_eq(s,global)) {
            level = level_one;
            f++;
        }
    }
    if (n-f == 2) {
        cattable = luaL_checkinteger(L, -3);
    }
    ch = luaL_checkinteger(L, -2);
    check_char_range(ch, "setcatcode", 65536*17);
    val = (halfword) luaL_checkinteger(L, -1);
    check_char_range(val, "setcatcode", 16);
    set_cat_code(cattable, ch, val, level);
    return 0;
}

static int getcatcode(lua_State * L)
{
    int cattable = cat_code_table_par;
    int ch = luaL_checkinteger(L, -1);
    if (lua_gettop(L)>=2 && lua_type(L,-2)==LUA_TNUMBER) {
        cattable = luaL_checkinteger(L, -2);
    }
    check_char_range(ch, "getcatcode",  65536*17);
    lua_pushinteger(L, get_cat_code(cattable, ch));
    return 1;
}

/*

static int setmathcode(lua_State * L)
{
    int ch;
    halfword cval, fval, chval;
    int level = cur_level;
    int n = lua_gettop(L);
    int f = 1;
    if (n>1 && lua_type(L,1) == LUA_TTABLE)
        f++;
    if (n>2 && (lua_type(L,f) == LUA_TSTRING)) {
        const char *s = lua_tostring(L, f);
        if (lua_key_eq(s,global)) {
            level = level_one;
            f++;
        }
    }
    if (n-f!=1 || lua_type(L,f+1) != LUA_TTABLE) {
        luaL_error(L, "Bad arguments for tex.setmathcode()");
    }
    ch = luaL_checkinteger(L, -2);
    check_char_range(ch, "setmathcode", 65536*17);

    lua_rawgeti(L, -1, 1);
    cval = (halfword) luaL_checkinteger(L, -1);
    lua_rawgeti(L, -2, 2);
    fval = (halfword) luaL_checkinteger(L, -1);
    lua_rawgeti(L, -3, 3);
    chval = (halfword) luaL_checkinteger(L, -1);
    lua_pop(L,3);

    check_char_range(cval, "setmathcode", 8);
    check_char_range(fval, "setmathcode", 256);
    check_char_range(chval, "setmathcode", 65536*17);
    set_math_code(ch, cval,fval, chval, (quarterword) (level));
    return 0;
}

*/

/*
    [global] code { c f ch }
    [global] code   c f ch   (a bit easier on memory, counterpart of getter)
*/

static int setmathcode(lua_State * L)
{
    int ch;
    halfword cval, fval, chval;
    int level = cur_level;
    int f = 1;
    if (lua_type(L,1) == LUA_TSTRING) {
        const char *s = lua_tostring(L,1);
        if (lua_key_eq(s,global)) {
            level = level_one;
            f = 2;
        }
    }
    ch = luaL_checkinteger(L, f);
    check_char_range(ch, "setmathcode", 65536*17);
    f += 1 ;
    if (lua_type(L,f) == LUA_TNUMBER) {
        cval = luaL_checkinteger(L, f);
        fval = luaL_checkinteger(L, f+1);
        chval = luaL_checkinteger(L, f+2);
    } else if (lua_type(L,f) == LUA_TTABLE) {
        lua_rawgeti(L, f, 1);
        cval = (halfword) luaL_checkinteger(L, -1);
        lua_rawgeti(L, f, 2);
        fval = (halfword) luaL_checkinteger(L, -1);
        lua_rawgeti(L, f, 3);
        chval = (halfword) luaL_checkinteger(L, -1);
        lua_pop(L,3);
    } else {
        luaL_error(L, "Bad arguments for tex.setmathcode()");
        return 0;
    }
    check_char_range(cval, "setmathcode", 8);
    check_char_range(fval, "setmathcode", 256);
    check_char_range(chval, "setmathcode", 65536*17);
    set_math_code(ch, cval,fval, chval, (quarterword) (level));
    return 0;
}

static int getmathcode(lua_State * L)
{
    mathcodeval mval = { 0, 0, 0 };
    int ch = luaL_checkinteger(L, -1);
    check_char_range(ch, "getmathcode",  65536*17);
    mval = get_math_code(ch);
    lua_newtable(L);
    lua_pushinteger(L,mval.class_value);
    lua_rawseti(L, -2, 1);
    lua_pushinteger(L,mval.family_value);
    lua_rawseti(L, -2, 2);
    lua_pushinteger(L,mval.character_value);
    lua_rawseti(L, -2, 3);
    return 1;
}

static int getmathcodes(lua_State * L)
{
    mathcodeval mval = { 0, 0, 0 };
    int ch = luaL_checkinteger(L, -1);
    check_char_range(ch, "getmathcodes",  65536*17);
    mval = get_math_code(ch);
    lua_pushinteger(L,mval.class_value);
    lua_pushinteger(L,mval.family_value);
    lua_pushinteger(L,mval.character_value);
    return 3;
}

/*

static int setdelcode(lua_State * L)
{
    int ch;
    halfword sfval, scval, lfval, lcval;
    int level = cur_level;
    int n = lua_gettop(L);
    int f = 1;
    if (n>1 && lua_type(L,1) == LUA_TTABLE)
        f++;
    if (n>2 && (lua_type(L,f) == LUA_TSTRING)) {
        const char *s = lua_tostring(L, f);
        if (lua_key_eq(s,global)) {
            level = level_one;
	    f++;
	}
    }
    if (n-f!=1 || lua_type(L,f+1) != LUA_TTABLE) {
	luaL_error(L, "Bad arguments for tex.setdelcode()");
    }
    ch = luaL_checkinteger(L, -2);
    check_char_range(ch, "setdelcode", 65536*17);
    lua_rawgeti(L, -1, 1);
    sfval = (halfword) luaL_checkinteger(L, -1);
    lua_rawgeti(L, -2, 2);
    scval = (halfword) luaL_checkinteger(L, -1);
    lua_rawgeti(L, -3, 3);
    lfval = (halfword) luaL_checkinteger(L, -1);
    lua_rawgeti(L, -4, 4);
    lcval = (halfword) luaL_checkinteger(L, -1);
    lua_pop(L,4);

    check_char_range(sfval, "setdelcode", 256);
    check_char_range(scval, "setdelcode", 65536*17);
    check_char_range(lfval, "setdelcode", 256);
    check_char_range(lcval, "setdelcode", 65536*17);
    set_del_code(ch, sfval, scval, lfval, lcval, (quarterword) (level));

    return 0;
}

*/

/*
    [global] code { c f ch }
    [global] code   c f ch   (a bit easier on memory, counterpart of getter)
*/

static int setdelcode(lua_State * L)
{
    int ch;
    halfword sfval, scval, lfval, lcval;
    int level = cur_level;
    int f = 1;
    if (lua_type(L,1) == LUA_TSTRING) {
        const char *s = lua_tostring(L,1);
        if (lua_key_eq(s,global)) {
            level = level_one;
            f = 2;
        }
    }
    ch = luaL_checkinteger(L, f);
    check_char_range(ch, "setdelcode", 65536*17);
    f += 1;
    if (lua_type(L,f) == LUA_TNUMBER) {
        sfval = luaL_checkinteger(L, f);
        scval = luaL_checkinteger(L, f+1);
        lfval = luaL_checkinteger(L, f+2);
        lcval = luaL_checkinteger(L, f+3);
    } else if (lua_type(L,f) == LUA_TTABLE) {
        lua_rawgeti(L, f, 1);
        sfval = (halfword) luaL_checkinteger(L, -1);
        lua_rawgeti(L, f, 2);
        scval = (halfword) luaL_checkinteger(L, -1);
        lua_rawgeti(L, f, 3);
        lfval = (halfword) luaL_checkinteger(L, -1);
        lua_rawgeti(L, f, 4);
        lcval = (halfword) luaL_checkinteger(L, -1);
        lua_pop(L,4);
    } else {
        luaL_error(L, "Bad arguments for tex.setdelcode()");
        return 0;
    }
    check_char_range(sfval, "setdelcode", 256);
    check_char_range(scval, "setdelcode", 65536*17);
    check_char_range(lfval, "setdelcode", 256);
    check_char_range(lcval, "setdelcode", 65536*17);
    set_del_code(ch, sfval, scval, lfval, lcval, (quarterword) (level));
    return 0;
}

static int getdelcode(lua_State * L)
{
    delcodeval mval = { 0, 0, 0, 0, 0 };
    int ch = luaL_checkinteger(L, -1);
    check_char_range(ch, "getdelcode",  65536*17);
    mval = get_del_code(ch);
    lua_newtable(L);
    lua_pushinteger(L,mval.small_family_value);
    lua_rawseti(L, -2, 1);
    lua_pushinteger(L,mval.small_character_value);
    lua_rawseti(L, -2, 2);
    lua_pushinteger(L,mval.large_family_value);
    lua_rawseti(L, -2, 3);
    lua_pushinteger(L,mval.large_character_value);
    lua_rawseti(L, -2, 4);
    return 1;
}

static int getdelcodes(lua_State * L)
{
    delcodeval mval = { 0, 0, 0, 0, 0 };
    int ch = luaL_checkinteger(L, -1);
    check_char_range(ch, "getdelcodes",  65536*17);
    mval = get_del_code(ch);
    lua_pushinteger(L,mval.small_family_value);
    lua_pushinteger(L,mval.small_character_value);
    lua_pushinteger(L,mval.large_family_value);
    lua_pushinteger(L,mval.large_character_value);
    return 4;
}

static int settex(lua_State * L)
{
    const char *st;
    int texstr, isprim;
    size_t k;
    int cur_cs1, cur_cmd1;
    int isglobal = 0;
    int j = 0;
    int i = lua_gettop(L);
    if (lua_type(L,i-1) == LUA_TSTRING) {
        st = lua_tolstring(L, (i - 1), &k);
        if (lua_key_eq(st,prevdepth)) {
            if (lua_type(L, i) == LUA_TNUMBER) {
                cur_list.prev_depth_field = lua_roundnumber(L, i);
            } else if (lua_type(L, i) == LUA_TSTRING) {
                cur_list.prev_depth_field = dimen_to_number(L, lua_tostring(L, i));
            } else {
                luaL_error(L, "unsupported value type");
            }
            return 0;
        } else if (lua_key_eq(st,prevgraf)) {
            if (lua_type(L, i) == LUA_TNUMBER) {
                cur_list.pg_field = lua_tointeger(L, i);
            } else {
                luaL_error(L, "unsupported value type");
            }
            return 0;
        } else if (lua_key_eq(st,spacefactor)) {
            if (lua_type(L, i) == LUA_TNUMBER) {
                cur_list.space_factor_field = lua_roundnumber(L, i);
            } else {
                luaL_error(L, "unsupported value type");
            }
            return 0;
        }
        texstr = maketexlstring(st, k);
        isprim = is_primitive(texstr);
        flush_str(texstr);
        if (isprim) {
            if (i == 3 && (lua_type(L,1) == LUA_TSTRING)) {
                const char *s = lua_tostring(L, 1);
                if (lua_key_eq(s,global))
                    isglobal = 1;
            }
            cur_cs1 = string_lookup(st, k);
            flush_str(texstr);
            cur_cmd1 = eq_type(cur_cs1);
            if (is_int_assign(cur_cmd1)) {
                if (lua_type(L, i) == LUA_TNUMBER) {
                    int luai = lua_tointeger(L, i);
                    assign_internal_value((isglobal ? 4 : 0), equiv(cur_cs1), luai);
                } else {
                    luaL_error(L, "unsupported value type");
                }
            } else if (is_dim_assign(cur_cmd1)) {
                if (lua_type(L, i) == LUA_TNUMBER) {
                    j = lua_roundnumber(L, i);
                } else if (lua_type(L, i) == LUA_TSTRING) {
                    j = dimen_to_number(L, lua_tostring(L, i));
                } else {
                    luaL_error(L, "unsupported value type");
                }
                assign_internal_value((isglobal ? 4 : 0), equiv(cur_cs1), j);
            } else if (is_glue_assign(cur_cmd1)) {
                int a = isglobal;
                if (lua_type(L, i) == LUA_TNUMBER) {
                    halfword value = copy_node(zero_glue);
                    width(value) = lua_roundnumber(L,i);
                    if (i > 1) { stretch(value) = lua_roundnumber(L,i+1); }
                    if (i > 3) { shrink(value) = lua_roundnumber(L,i+2); }
                    if (i > 4) { stretch_order(value) = lua_tointeger(L,i+3); }
                    if (i > 5) { shrink_order(value) = lua_tointeger(L,i+4); }
                    define(equiv(cur_cs1), assign_glue_cmd, value);
                } else {
                    halfword *j1 = check_isnode(L, i);     /* the value */
                    define(equiv(cur_cs1), assign_glue_cmd, *j1);
                }
            } else if (is_toks_assign(cur_cmd1)) {
                if (lua_type(L,i) == LUA_TSTRING) {
                    j = tokenlist_from_lua(L);  /* uses stack -1 */
                    assign_internal_value((isglobal ? 4 : 0), equiv(cur_cs1), j);

                } else {
                    luaL_error(L, "unsupported value type");
                }

            } else if (lua_istable(L, (i - 2))) {
                /*
                    people may want to add keys that are also primitives |tex.wd| for example)
                    so creating an error is not right here
                */
                lua_rawset(L, (i - 2));
            }
        } else if (lua_istable(L, (i - 2))) {
            lua_rawset(L, (i - 2));
        }
    } else if (lua_istable(L, (i - 2))) {
        lua_rawset(L, (i - 2));
    }
    return 0;
}

/* todo: some will to the pdf namespace  .. ignore > 31 */

static int do_convert(lua_State * L, int cur_code)
{
    int texstr;
    int i = -1;
    char *str = NULL;
    switch (cur_code) {
        /* ignored (yet) */

        case insert_ht_code:               /* arg <register int> */
        case lua_code:                     /* arg complex */
        case lua_escape_string_code:       /* arg token list */
        case left_margin_kern_code:        /* arg box */
        case right_margin_kern_code:       /* arg box */
        case string_code:                  /* arg token */
        case cs_string_code:               /* arg token */
        case meaning_code:                 /* arg token */
            break;

        /* the next fall through, and come from 'official' indices! */

        case font_name_code:               /* arg fontid */
        case font_identifier_code:         /* arg fontid */
        case uniform_deviate_code:         /* arg int */
        case number_code:                  /* arg int */
        case roman_numeral_code:           /* arg int */

            if (lua_gettop(L) < 1) {
                /* error */
            }
            i = lua_tointeger(L, 1);

            /* these fall through! */

        default:
            /* no backend here */
            if (cur_code < 32) {
                texstr = the_convert_string(cur_code, i);
                if (texstr) {
                    str = makecstring(texstr);
                    flush_str(texstr);
                }
            }
    }
    /* end */
    if (str) {
        lua_pushstring(L, str);
        free(str);
    } else {
        lua_pushnil(L);
    }
    return 1;
}

static int do_scan_internal(lua_State * L, int cur_cmd1, int cur_code, int values)
{
    int texstr;
    int retval = 1 ;
    char *str = NULL;
    int save_cur_val, save_cur_val_level;
    save_cur_val = cur_val;
    save_cur_val_level = cur_val_level;
    scan_something_simple(cur_cmd1, cur_code);
    switch (cur_val_level) {
        case int_val_level:
        case dimen_val_level:
        case attr_val_level:
            lua_pushinteger(L, cur_val);
            break;
        case glue_val_level:
        case mu_val_level:
            if (values == 0) {
                lua_pushinteger(L,width(cur_val));
                flush_node(cur_val);
            } else if (values == 1) {
                lua_pushinteger(L,width(cur_val));
                lua_pushinteger(L,stretch(cur_val));
                lua_pushinteger(L,shrink(cur_val));
                lua_pushinteger(L,stretch_order(cur_val));
                lua_pushinteger(L,shrink_order(cur_val));
                flush_node(cur_val);
                retval = 5;
            } else {
                lua_nodelib_push_fast(L, cur_val);
            }
            break;
        default:
            texstr = the_scanned_result();
            str = makecstring(texstr);
            if (str) {
                lua_pushstring(L, str);
                free(str);
            } else {
                lua_pushnil(L);
            }
            flush_str(texstr);
            break;
    }
    cur_val = save_cur_val;
    cur_val_level = save_cur_val_level;
    return retval;
}

static int do_lastitem(lua_State * L, int cur_code)
{
    int retval = 1;
    switch (cur_code) {
        /* the next two do not actually exist */
        case lastattr_code:
        case attrexpr_code:
            lua_pushnil(L);
            break;
            /* the expressions do something complicated with arguments, yuck */
        case numexpr_code:
        case dimexpr_code:
        case glueexpr_code:
        case muexpr_code:
            lua_pushnil(L);
            break;
            /* these read a glue or muglue, todo */
        case mu_to_glue_code:
        case glue_to_mu_code:
        case glue_stretch_order_code:
        case glue_shrink_order_code:
        case glue_stretch_code:
        case glue_shrink_code:
            lua_pushnil(L);
            break;
            /* these read a fontid and a char, todo */
        case font_char_wd_code:
        case font_char_ht_code:
        case font_char_dp_code:
        case font_char_ic_code:
            lua_pushnil(L);
            break;
            /* these read an integer, todo */
        case par_shape_length_code:
        case par_shape_indent_code:
        case par_shape_dimen_code:
            lua_pushnil(L);
            break;
        case lastpenalty_code:
        case lastkern_code:
        case lastskip_code:
        case last_node_type_code:
        case input_line_no_code:
        case badness_code:
        case last_saved_box_resource_index_code:
        case last_saved_image_resource_index_code:
        case last_saved_image_resource_pages_code:
        case last_x_pos_code:
        case last_y_pos_code:
        case random_seed_code:
        case luatex_version_code:
        case eTeX_minor_version_code:
        case eTeX_version_code:
        case current_group_level_code:
        case current_group_type_code:
        case current_if_level_code:
        case current_if_type_code:
        case current_if_branch_code:
            retval = do_scan_internal(L, last_item_cmd, cur_code, -1);
            break;
        default:
            lua_pushnil(L);
            break;
    }
    return retval;
}

static int tex_setmathparm(lua_State * L)
{
    int i, j;
    int k;
    int l = cur_level;
    void *p;
    int n = lua_gettop(L);
    if ((n == 3) || (n == 4)) {
        if (n == 4 && (lua_type(L,1) == LUA_TSTRING)) {
            const char *s = lua_tostring(L, 1);
            if (lua_key_eq(s,global))
                l = 1;
        }
        i = luaL_checkoption(L, (n - 2), NULL, math_param_names);
        j = luaL_checkoption(L, (n - 1), NULL, math_style_names);
        if (i < 0 || j < 0) {
            /* invalid spec, just ignore it  */
        } else if (i>=math_param_first_mu_glue) {
            p = lua_touserdata(L, n);
            k = *((halfword *)p);
            def_math_param(i, j, (scaled) k, l);
        } else if (lua_type(L, n) == LUA_TNUMBER) {
            k = lua_roundnumber(L, n);
            def_math_param(i, j, (scaled) k, l);
        } else {
            luaL_error(L, "argument must be a number");
        }
    }
    return 0;
}

static int tex_getmathparm(lua_State * L)
{
    if (lua_gettop(L) == 2) {
        int i = luaL_checkoption(L, 1, NULL, math_param_names);
        int j = luaL_checkoption(L, 2, NULL, math_style_names);
        if (i < 0 || j < 0) {
            lua_pushnil(L);
        } else {
            scaled k = get_math_param(i, j);
            if (i >= math_param_first_mu_glue) {
                if (k <= thick_mu_skip_code) {
                    k = glue_par(k);
                }
                lua_nodelib_push_fast(L, k);
            } else {
                lua_pushinteger(L, k);
            }
        }
    } else {
        lua_pushnil(L);
    }
    return 1;
}

static int getfontname(lua_State * L)
{
    return do_convert(L, font_name_code);
}

static int getfontidentifier(lua_State * L)
{
    return do_convert(L, font_identifier_code);
}

static int getuniformdeviate(lua_State * L)
{
    return do_convert(L, uniform_deviate_code);
}

static int getnumber(lua_State * L)
{
    return do_convert(L, number_code);
}

static int getromannumeral(lua_State * L)
{
    return do_convert(L, roman_numeral_code);
}

static int get_parshape(lua_State * L)
{
    halfword par_shape_ptr = par_shape_par_ptr;
    if (par_shape_ptr != 0) {
        int m = 1;
        int n = vinfo(par_shape_ptr + 1);
        lua_createtable(L, n, 0);
        while (m <= n) {
            lua_createtable(L, 2, 0);
            lua_pushinteger(L, vlink((par_shape_ptr) + (2 * (m - 1)) + 2));
            lua_rawseti(L, -2, 1);
            lua_pushinteger(L, vlink((par_shape_ptr) + (2 * (m - 1)) + 3));
            lua_rawseti(L, -2, 2);
            lua_rawseti(L, -2, m);
            m++;
        }
    } else {
        lua_pushnil(L);
    }
    return 1;
}

static int gettex(lua_State * L)
{
    int cur_cs1 = -1;
    int retval = 1; /* default is to return nil  */
    int t = lua_gettop(L);
    int b = -1 ;
    if (t > 1 && lua_type(L,t) == LUA_TBOOLEAN) {
        /*
             0 == flush width only
             1 == flush all glue parameters
        */
        b = lua_toboolean(L,t);
        t = t - 1;
    }
    if (lua_type(L,t) == LUA_TSTRING) {
        /*
            1 == tex
            2 == boxmaxdepth
                or
            1 == boxmaxdepth
        */
        int texstr;
        size_t k;
        const char *st = lua_tolstring(L, t, &k);
        if (lua_key_eq(st,prevdepth)) {
            lua_pushinteger(L, cur_list.prev_depth_field);
            return 1;
        } else if (lua_key_eq(st,prevgraf)) {
            lua_pushinteger(L, cur_list.pg_field);
            return 1;
        } else if (lua_key_eq(st,spacefactor)) {
            lua_pushinteger(L, cur_list.space_factor_field);
            return 1;
        }
        texstr = maketexlstring(st, k);
        cur_cs1 = prim_lookup(texstr);   /* not found == relax == 0 */
        flush_str(texstr);
    }
    if (cur_cs1 > 0) {
        int cur_cmd1 = get_prim_eq_type(cur_cs1);
        int cur_code = get_prim_equiv(cur_cs1);
        switch (cur_cmd1) {
            case last_item_cmd:
                retval = do_lastitem(L, cur_code);
                break;
            case convert_cmd:
                retval = do_convert(L, cur_code);
                break;
            case assign_toks_cmd:
            case assign_int_cmd:
            case assign_attr_cmd:
            case assign_dir_cmd:
            case assign_direction_cmd:
            case assign_dimen_cmd:
            case set_aux_cmd:
            case set_prev_graf_cmd:
            case set_page_int_cmd:
            case set_page_dimen_cmd:
            case char_given_cmd:
            case math_given_cmd:
                retval = do_scan_internal(L, cur_cmd1, cur_code, -1);
                break;
            case assign_glue_cmd:
            case assign_mu_glue_cmd:
                retval = do_scan_internal(L, cur_cmd1, cur_code, b);
                break;
            case set_tex_shape_cmd:
                retval = get_parshape(L);
                break;
            default:
                lua_pushnil(L);
                break;
        }
    } else if ((t == 2) && (lua_type(L,2) == LUA_TSTRING)) {
	    lua_rawget(L, 1);
    }
    return retval;
}

static int getlist(lua_State * L)
{
    const char *str;
    int top = lua_gettop(L);
    if (lua_type(L,top) == LUA_TSTRING) {
        str = lua_tostring(L, top);
        if (lua_key_eq(str,page_ins_head)) {
            if (vlink(page_ins_head) == page_ins_head)
                lua_pushinteger(L, null);
            else
                lua_pushinteger(L, vlink(page_ins_head));
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,contrib_head)) {
            alink(vlink(contrib_head)) = null ;
            lua_pushinteger(L, vlink(contrib_head));
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,page_discards_head)) {
            alink(vlink(page_disc)) = null ;
            lua_pushinteger(L, page_disc);
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,split_discards_head)) {
            alink(vlink(split_disc)) = null ;
            lua_pushinteger(L, split_disc);
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,page_head)) {
            alink(vlink(page_head)) = null ;/*hh-ls */
            lua_pushinteger(L, vlink(page_head));
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,temp_head)) {
            alink(vlink(temp_head)) = null ;/*hh-ls */
            lua_pushinteger(L, vlink(temp_head));
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,hold_head)) {
            alink(vlink(hold_head)) = null ;/*hh-ls */
            lua_pushinteger(L, vlink(hold_head));
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,adjust_head)) {
            alink(vlink(adjust_head)) = null ;/*hh-ls */
            lua_pushinteger(L, vlink(adjust_head));
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,best_page_break)) {
            lua_pushinteger(L, best_page_break);
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,least_page_cost)) {
            lua_pushinteger(L, least_page_cost);
        } else if (lua_key_eq(str,best_size)) {
            lua_pushinteger(L, best_size);
        } else if (lua_key_eq(str,pre_adjust_head)) {
            alink(vlink(pre_adjust_head)) = null ;/*hh-ls */
            lua_pushinteger(L, vlink(pre_adjust_head));
            lua_nodelib_push(L);
        } else if (lua_key_eq(str,align_head)) {
            alink(vlink(align_head)) = null ;/*hh-ls */
            lua_pushinteger(L, vlink(align_head));
            lua_nodelib_push(L);
        } else {
            lua_pushnil(L);
        }
    } else {
        lua_pushnil(L);
    }
    return 1;
}

static int setlist(lua_State * L)
{
    int top = (lua_type(L,1) == LUA_TTABLE) ? 2 : 1 ;
    if (lua_type(L,top) == LUA_TSTRING) {
        const char *str = lua_tostring(L, top);
        if (lua_key_eq(str,best_size)) {
            best_size = (int) lua_tointeger(L, top+1);
        } else if (lua_key_eq(str,least_page_cost)) {
            least_page_cost = (int) lua_tointeger(L, top+1);
        } else {
            halfword *n_ptr;
            halfword n = 0;
            if (!lua_isnil(L, top+1)) {
                n_ptr = check_isnode(L, top+1);
                n = *n_ptr;
            }
            if (lua_key_eq(str,page_ins_head)) {
                if (n == 0) {
                    vlink(page_ins_head) = page_ins_head;
                } else {
                    halfword m;
                    vlink(page_ins_head) = n;
                    m = tail_of_list(n);
                    vlink(m) = page_ins_head;
                }
            } else if (lua_key_eq(str,contrib_head)) {
                vlink(contrib_head) = n;
                if (n == 0) {
                    contrib_tail = contrib_head;
                }
            } else if (lua_key_eq(str,best_page_break)) {
                best_page_break = n;
            } else if (lua_key_eq(str,page_head)) {
                vlink(page_head) = n;
                page_tail = (n == 0 ? page_head : tail_of_list(n));
            } else if (lua_key_eq(str,temp_head)) {
                vlink(temp_head) = n;
            } else if (lua_key_eq(str,page_discards_head)) {
                page_disc = n;
            } else if (lua_key_eq(str,split_discards_head)) {
                split_disc = n;
            } else if (lua_key_eq(str,hold_head)) {
                vlink(hold_head) = n;
            } else if (lua_key_eq(str,adjust_head)) {
                vlink(adjust_head) = n;
                adjust_tail = (n == 0 ? adjust_head : tail_of_list(n));
            } else if (lua_key_eq(str,pre_adjust_head)) {
                vlink(pre_adjust_head) = n;
                pre_adjust_tail = (n == 0 ? pre_adjust_head : tail_of_list(n));
            } else if (lua_key_eq(str,align_head)) {
                vlink(align_head) = n;
            }
        }
    }
    return 0;
}

#define NEST_METATABLE "luatex.nest"

static int lua_nest_getfield(lua_State * L)
{
    list_state_record *r, **rv = lua_touserdata(L, -2);
    const char *field = lua_tostring(L, -1);
    r = *rv;
    if (lua_key_eq(field,mode)) {
        lua_pushinteger(L, r->mode_field);
    } else if (lua_key_eq(field,head)) {
        lua_nodelib_push_fast(L, r->head_field);
    } else if (lua_key_eq(field,tail)) {
        lua_nodelib_push_fast(L, r->tail_field);
    } else if (lua_key_eq(field,delimptr)) {
        lua_pushinteger(L, r->eTeX_aux_field);
        lua_nodelib_push(L);
    } else if (lua_key_eq(field,prevgraf)) {
        lua_pushinteger(L, r->pg_field);
    } else if (lua_key_eq(field,modeline)) {
        lua_pushinteger(L, r->ml_field);
    } else if (lua_key_eq(field,prevdepth)) {
        lua_pushinteger(L, r->prev_depth_field);
    } else if (lua_key_eq(field,spacefactor)) {
        lua_pushinteger(L, r->space_factor_field);
    } else if (lua_key_eq(field,noad)) {
        lua_pushinteger(L, r->incompleat_noad_field);
        lua_nodelib_push(L);
    } else if (lua_key_eq(field,dirs)) {
        lua_pushinteger(L, r->dirs_field);
        lua_nodelib_push(L);
    } else if (lua_key_eq(field,mathdir)) {
        lua_pushboolean(L, r->math_field);
    } else if (lua_key_eq(field,mathstyle)) {
        lua_pushinteger(L, r->math_style_field);
    } else {
        lua_pushnil(L);
    }
    return 1;
}

static int lua_nest_setfield(lua_State * L)
{
    halfword *n;
    int i;
    list_state_record *r, **rv = lua_touserdata(L, -3);
    const char *field = lua_tostring(L, -2);
    r = *rv;
    if (lua_key_eq(field,mode)) {
        i = lua_tointeger(L, -1);
        r->mode_field = i;
    } else if (lua_key_eq(field,head)) {
        n = check_isnode(L, -1);
        r->head_field = *n;
    } else if (lua_key_eq(field,tail)) {
        n = check_isnode(L, -1);
        r->tail_field = *n;
    } else if (lua_key_eq(field,delimptr)) {
        n = check_isnode(L, -1);
        r->eTeX_aux_field = *n;
    } else if (lua_key_eq(field,prevgraf)) {
        i = lua_tointeger(L, -1);
        r->pg_field = i;
    } else if (lua_key_eq(field,modeline)) {
        i = lua_tointeger(L, -1);
        r->ml_field = i;
    } else if (lua_key_eq(field,prevdepth)) {
        i = lua_roundnumber(L, -1);
        r->prev_depth_field = i;
    } else if (lua_key_eq(field,spacefactor)) {
        i = lua_roundnumber(L, -1);
        r->space_factor_field = i;
    } else if (lua_key_eq(field,noad)) {
        n = check_isnode(L, -1);
        r->incompleat_noad_field = *n;
    } else if (lua_key_eq(field,dirs)) {
        n = check_isnode(L, -1);
        r->dirs_field = *n;
    } else if (lua_key_eq(field,mathdir)) {
        r->math_field = lua_toboolean(L, -1);
    } else if (lua_key_eq(field,mathstyle)) {
        i = lua_tointeger(L, -1);
        r->math_style_field = i;
    }
    return 0;
}

static const struct luaL_Reg nest_m[] = {
    {"__index", lua_nest_getfield},
    {"__newindex", lua_nest_setfield},
    {NULL, NULL}                /* sentinel */
};

static void init_nest_lib(lua_State * L)
{
    luaL_newmetatable(L, NEST_METATABLE);
    luaL_openlib(L, NULL, nest_m, 0);
    lua_pop(L, 1);
}

static int getnest(lua_State * L)
{
    list_state_record **nestitem;
    int n = lua_gettop(L);
    int p = -1 ;
    if (n == 0) {
        p = nest_ptr;
    } else {
        int t = lua_type(L, n);
        if (t == LUA_TNUMBER) {
            int ptr = lua_tointeger(L, n);
            if (ptr >= 0 && ptr <= nest_ptr) {
                p = ptr;
            }
        } else if (t == LUA_TSTRING) {
            const char *s = lua_tostring(L, n);
            if (lua_key_eq(s,top)) {
                p = nest_ptr;
            } else if (lua_key_eq(s,ptr)) {
                lua_pushinteger(L, nest_ptr);
                return 1;
            }
        }
    }
    if (p > -1) {
        nestitem = lua_newuserdata(L, sizeof(list_state_record *));
        *nestitem = &nest[p];
        luaL_getmetatable(L, NEST_METATABLE);
        lua_setmetatable(L, -2);
    } else {
        lua_pushnil(L);
    }
    return 1;
}

static int setnest(lua_State * L)
{
    luaL_error(L, "You can't modify the semantic nest array directly");
    return 0;
}

static int do_integer_error(double m)
{
    const char *help[] = {
        "I can only go up to 2147483647='17777777777=" "7FFFFFFF,",
        "so I'm using that number instead of yours.",
        NULL
    };
    tex_error("Number too big", help);
    return (m > 0.0 ? infinity : -infinity);
}

static int tex_roundnumber(lua_State * L)
{
    double m = (double) lua_tonumber(L, 1) + 0.5; /* integer or float */
    if (abs(m) > (double) infinity)
        lua_pushinteger(L, do_integer_error(m));
    else
        lua_pushinteger(L, floor(m));
    return 1;
}

static int tex_scaletable(lua_State * L)
{
    double delta = luaL_checknumber(L, 2);
    if (lua_istable(L, 1)) {
        lua_newtable(L);        /* the new table is at index 3 */
        lua_pushnil(L);
        while (lua_next(L, 1) != 0) {   /* numeric value */
            lua_pushvalue(L, -2);
            lua_insert(L, -2);
            if (lua_type(L,-2) == LUA_TNUMBER) {
                double m = (double) lua_tonumber(L, -1) * delta + 0.5; /* integer or float */
                lua_pop(L, 1);
                if (abs(m) > (double) infinity)
                    lua_pushinteger(L, do_integer_error(m));
                else
                    lua_pushinteger(L, floor(m));
            }
            lua_rawset(L, 3);
        }
    } else if (lua_type(L,1) == LUA_TNUMBER) {
        double m = (double) lua_tonumber(L, 1) * delta + 0.5; /* integer or float */
        if (abs(m) > (double) infinity)
            lua_pushinteger(L, do_integer_error(m));
        else
            lua_pushinteger(L, floor(m));
    } else {
        lua_pushnil(L);
    }
    return 1;
}

#define hash_text(A) hash[(A)].rh

static int tex_definefont(lua_State * L)
{
    const char *csname;
    int f, u;
    str_number t, d;
    size_t l;
    int i = 1;
    int a = 0;
    if (!no_new_control_sequence) {
        const char *help[] = { "You can't create a new font inside a \\csname\\endcsname pair", NULL };
        tex_error("Definition active", help);
    }
    if ((lua_gettop(L) == 3) && lua_isboolean(L, 1)) {
        a = lua_toboolean(L, 1);
        i = 2;
    }
    csname = luaL_checklstring(L, i, &l);
    f = luaL_checkinteger(L, (i + 1));
    no_new_control_sequence = 0;
    u = string_lookup(csname, l);
    no_new_control_sequence = 1;
    if (a)
        geq_define(u, set_font_cmd, f);
    else
        eq_define(u, set_font_cmd, f);
    eqtb[font_id_base + f] = eqtb[u];
    /*tex

        This is tricky: when we redefine a string we loose the old one. So this
        will change as it's only used to display the |\fontname| so we can store
        that with the font.

    */
    d = cs_text(font_id_base + f);
    t = maketexlstring(csname, l); /* the csname */
    if (!d) {
        /*tex We have a new string. */
        cs_text(font_id_base + f) = t;
    } else if ((d!=t) && str_eq_str(d,t)){
        /*tex We have a duplicate string. */
        flush_str(t);
    } else if(d!=t){
        d = search_string(t);
        if (d) {
            /*tex We have already such a string. */
            cs_text(font_id_base + f) = d;
            flush_str(t);
        } else {
            /*tex The old value is lost but still in the pool. */
            cs_text(font_id_base + f) = t;
        }
    }
    return 0;
}

/*
static int tex_hashpairs(lua_State * L)
{
    int cmd, chr;
    str_number s = 0;
    int cs = 1;
    lua_newtable(L);
    while (cs < hash_size) {
        s = hash_text(cs);
        if (s > 0) {
            char *ss = makecstring(s);
            lua_pushstring(L, ss);
            free(ss);
            cmd = eq_type(cs);
            chr = equiv(cs);
            make_token_table(L, cmd, chr, cs);
            lua_rawset(L, -3);
            cs++;
        }
    }
    return 1;
}

static int tex_primitives(lua_State * L)
{
    int cmd, chr;
    str_number s = 0;
    int cs = 0;
    lua_newtable(L);
    while (cs < prim_size) {
        s = get_prim_text(cs);
        if (s > 0) {
            char *ss = makecstring(s);
            lua_pushstring(L, ss);
            free(ss);
            cmd = get_prim_eq_type(cs);
            chr = get_prim_equiv(cs);
            make_token_table(L, cmd, chr, 0);
            lua_rawset(L, -3);
        }
        cs++;
    }
    return 1;
}

static int tex_extraprimitives(lua_State * L)
{
    int n, i;
    int mask = 0;
    int cs = 0;
    n = lua_gettop(L);
    if (n == 0) {
        mask = etex_command + luatex_command;
    } else {
        for (i = 1; i <= n; i++) {
            if (lua_type(L,i) == LUA_TSTRING) {
                const char *s = lua_tostring(L, i);
                if (lua_key_eq(s,etex)) {
                    mask |= etex_command;
                } else if (lua_key_eq(s,tex)) {
                    mask |= tex_command;
                } else if (lua_key_eq(s,core)) {
                    mask |= core_command;
                } else if (lua_key_eq(s,luatex)) {
                    mask |= luatex_command;
                }
            }
        }
    }
    lua_newtable(L);
    i = 1;
    while (cs < prim_size) {
	str_number s = 0;
        s = get_prim_text(cs);
        if (s > 0) {
            if (get_prim_origin(cs) & mask) {
                char *ss = makecstring(s);
                lua_pushstring(L, ss);
                free(ss);
                lua_rawseti(L, -2, i++);
            }
        }
        cs++;
    }
    return 1;
}

*/

static int tex_hashpairs(lua_State * L)
{
    str_number s = 0;
    int cs = 1;
    int nt = 0;
    lua_newtable(L);
    while (cs < hash_size) {
        s = hash_text(cs);
        if (s > 0) {
            char *ss = makecstring(s);
            lua_pushstring(L, ss);
            free(ss);
            lua_rawseti(L, -2, ++nt);
        }
        cs++;
    }
    return 1;
}

static int tex_primitives(lua_State * L)
{
    str_number s = 0;
    int cs = 0;
    int nt = 0;
    lua_newtable(L);
    while (cs < prim_size) {
        s = get_prim_text(cs);
        if (s > 0) {
            char *ss = makecstring(s);
            lua_pushstring(L, ss);
            free(ss);
            lua_rawseti(L, -2, ++nt);
        }
        cs++;
    }
    return 1;
}

static int tex_extraprimitives(lua_State * L)
{
    int n, i;
    int mask = 0;
    int cs = 0;
    int nt = 0;
    n = lua_gettop(L);
    if (n == 0) {
        mask = etex_command + luatex_command;
    } else {
        for (i = 1; i <= n; i++) {
            if (lua_type(L,i) == LUA_TSTRING) {
                const char *s = lua_tostring(L, i);
                if (lua_key_eq(s,etex)) {
                    mask |= etex_command;
                } else if (lua_key_eq(s,tex)) {
                    mask |= tex_command;
                } else if (lua_key_eq(s,core)) {
                    mask |= core_command;
                } else if (lua_key_eq(s,luatex)) {
                    mask |= luatex_command;
                }
            }
        }
    }
    lua_newtable(L);
    while (cs < prim_size) {
        str_number s = 0;
        s = get_prim_text(cs);
        if (s > 0) {
            if (get_prim_origin(cs) & mask) {
                char *ss = makecstring(s);
                lua_pushstring(L, ss);
                free(ss);
                lua_rawseti(L, -2, ++nt);
            }
        }
        cs++;
    }
    return 1;
}

static int tex_enableprimitives(lua_State * L)
{
    int n = lua_gettop(L);
    if (n != 2) {
        luaL_error(L, "wrong number of arguments");
    } else {
        size_t l;
        int i;
        const char *pre = luaL_checklstring(L, 1, &l);
        if (lua_istable(L, 2)) {
            int nncs = no_new_control_sequence;
            no_new_control_sequence = true;
            i = 1;
            while (1) {
                lua_rawgeti(L, 2, i);
                if (lua_type(L,3) == LUA_TSTRING) {
                    const char *prim = lua_tostring(L, 3);
                    str_number s = maketexstring(prim);
                    halfword prim_val = prim_lookup(s);
                    if (prim_val != undefined_primitive) {
                        char *newprim;
                        int val;
                        size_t newl;
                        halfword cur_cmd1 = get_prim_eq_type(prim_val);
                        halfword cur_chr1 = get_prim_equiv(prim_val);
                        if (strncmp(pre, prim, l) != 0) {       /* not a prefix */
                            newl = strlen(prim) + l;
                            newprim = (char *) xmalloc((unsigned) (newl + 1));
                            strcpy(newprim, pre);
                            strcat(newprim + l, prim);
                        } else {
                            newl = strlen(prim);
                            newprim = (char *) xmalloc((unsigned) (newl + 1));
                            strcpy(newprim, prim);
                        }
                        val = string_lookup(newprim, newl);
                        if (val == undefined_control_sequence ||
                            eq_type(val) == undefined_cs_cmd) {
                            primitive_def(newprim, newl, (quarterword) cur_cmd1, cur_chr1);
                        }
                        free(newprim);
                    }
                    flush_str(s);
                } else {
                    lua_pop(L, 1);
                    break;
                }
                lua_pop(L, 1);
                i++;
            }
            lua_pop(L, 1);      /* the table */
            no_new_control_sequence = nncs;
        } else {
            luaL_error(L, "Expected an array of names as second argument");
        }
    }
    return 0;
}

#define get_int_par(A,B) do {             \
    lua_key_rawgeti(A);                   \
    if (lua_type(L, -1) == LUA_TNUMBER) { \
        A = (int) lua_tointeger(L, -1);   \
    } else {                              \
        A = (B);                          \
    }                                     \
    lua_pop(L,1);                         \
} while (0)

#define get_intx_par(A,B,C,D)  do {                \
    lua_key_rawgeti(A);                            \
    if (lua_type(L, -1) == LUA_TNUMBER) {          \
        A = (int) lua_tointeger(L, -1);            \
        C = null;                                  \
    } else if (lua_type(L, -1) == LUA_TTABLE){     \
        A = 0;                                     \
        C = nodelib_topenalties(L, lua_gettop(L)); \
    } else {                                       \
        A = (B);                                   \
        C = (D);                                   \
    }                                              \
    lua_pop(L,1);                                  \
} while (0)

#define get_dimen_par(A,B)  do {          \
    lua_key_rawgeti(A);                   \
    if (lua_type(L, -1) == LUA_TNUMBER) { \
        A = (int) lua_roundnumber(L, -1); \
    } else {                              \
        A = (B);                          \
    }                                     \
    lua_pop(L,1);                         \
} while (0)

#define get_glue_par(A,B)  do {        \
    lua_key_rawgeti(A);                \
    if (lua_type(L, -1) != LUA_TNIL) { \
        A = *check_isnode(L, -1);      \
    } else {                           \
        A = (B);                       \
    }                                  \
    lua_pop(L,1);                      \
} while (0)

static halfword nodelib_toparshape(lua_State * L, int i)
{
    halfword p;
    int n = 0;
    int width, indent, j;
    /* find |n| */
    lua_pushnil(L);
    while (lua_next(L, i) != 0) {
        n++;
        lua_pop(L, 1);
    }
    if (n == 0)
        return null;
    p = new_node(shape_node, 2 * (n + 1) + 1);
    vinfo(p + 1) = n;
    /* fill |p| */
    lua_pushnil(L);
    j = 0;
    while (lua_next(L, i) != 0) {
        /* don't give an error for non-tables, we may add special syntaxes at some point */
        j++;
        if (lua_type(L, i) == LUA_TTABLE) {
            lua_rawgeti(L, -1, 1);      /* indent */
            if (lua_type(L, -1) == LUA_TNUMBER) {
                indent = lua_roundnumber(L, -1);
                lua_pop(L, 1);
                lua_rawgeti(L, -1, 2);  /* width */
                if (lua_type(L, -1) == LUA_TNUMBER) {
                    width = lua_roundnumber(L, -1);
                    lua_pop(L, 1);
                    varmem[p + 2 * j].cint = indent;
                    varmem[p + 2 * j + 1].cint = width;
                }
            }
        }
        lua_pop(L, 1);
    }
    return p;
}

/* penalties */

static halfword nodelib_topenalties(lua_State * L, int i)
{
    halfword p;
    int n = 0;
    int j;
    /* find |n| */
    lua_pushnil(L);
    while (lua_next(L, i) != 0) {
        n++;
        lua_pop(L, 1);
    }
    if (n == 0)
        return null;
    p = new_node(shape_node, 2 * ((n / 2) + 1) + 1 + 1);
    vinfo(p + 1) = (n / 2) + 1;
    varmem[p + 2].cint = n;
    lua_pushnil(L);
    j = 2;
    while (lua_next(L, i) != 0) {
        j++;
        if (lua_type(L, -1) == LUA_TNUMBER) {
            int pen = lua_tointeger(L, -1);
            varmem[p+j].cint = pen;
        }
        lua_pop(L, 1);
    }
    if (!odd(n))
        varmem[p+j+1].cint = 0;
    return p;
}

static int tex_run_linebreak(lua_State * L)
{

    halfword *j;
    halfword p;
    halfword final_par_glue;
    int paragraph_dir = 0;
    /* locally initialized parameters for line breaking */
    int pretolerance, tracingparagraphs, tolerance, looseness,
        adjustspacing, adjdemerits, protrudechars,
        linepenalty, lastlinefit, doublehyphendemerits, finalhyphendemerits,
        hangafter, interlinepenalty, widowpenalty, clubpenalty, brokenpenalty;
    halfword emergencystretch, hangindent, hsize, leftskip, rightskip,parshape;
    int fewest_demerits = 0, actual_looseness = 0;
    halfword clubpenalties, interlinepenalties, widowpenalties;
    int save_vlink_tmp_head;
    /* push a new nest level */
    push_nest();
    save_vlink_tmp_head = vlink(temp_head);

    j = check_isnode(L, 1);     /* the value */
    vlink(temp_head) = *j;
    p = *j;
    if ((!is_char_node(vlink(*j))) && ((type(vlink(*j)) == local_par_node))) {
        paragraph_dir = local_par_dir(vlink(*j));
    }

    while (vlink(p) != null)
        p = vlink(p);
    final_par_glue = p;

    /* initialize local parameters */

    if (lua_gettop(L) != 2 || lua_type(L, 2) != LUA_TTABLE) {
        lua_checkstack(L, 3);
        lua_newtable(L);
    }
    lua_key_rawgeti(pardir);
    if (lua_type(L, -1) == LUA_TSTRING) {
        paragraph_dir = nodelib_getdir(L, -1);
    }
    lua_pop(L, 1);

    lua_key_rawgeti(parshape);
    if (lua_type(L, -1) == LUA_TTABLE) {
        parshape = nodelib_toparshape(L, lua_gettop(L));
    } else {
        parshape = equiv(par_shape_loc);
    }
    lua_pop(L, 1);

    get_int_par  (pretolerance, pretolerance_par);
    get_int_par  (tracingparagraphs, tracing_paragraphs_par);
    get_int_par  (tolerance, tolerance_par);
    get_int_par  (looseness, looseness_par);
    get_int_par  (adjustspacing, adjust_spacing_par);
    get_int_par  (adjdemerits, adj_demerits_par);
    get_int_par  (protrudechars, protrude_chars_par);
    get_int_par  (linepenalty, line_penalty_par);
    get_int_par  (lastlinefit, last_line_fit_par);
    get_int_par  (doublehyphendemerits, double_hyphen_demerits_par);
    get_int_par  (finalhyphendemerits, final_hyphen_demerits_par);
    get_int_par  (hangafter, hang_after_par);
    get_intx_par (interlinepenalty,inter_line_penalty_par, interlinepenalties, equiv(inter_line_penalties_loc));
    get_intx_par (clubpenalty, club_penalty_par, clubpenalties, equiv(club_penalties_loc));
    get_intx_par (widowpenalty, widow_penalty_par, widowpenalties, equiv(widow_penalties_loc));
    get_int_par  (brokenpenalty, broken_penalty_par);
    get_dimen_par(emergencystretch, emergency_stretch_par);
    get_dimen_par(hangindent, hang_indent_par);
    get_dimen_par(hsize, hsize_par);
    get_glue_par (leftskip, left_skip_par);
    get_glue_par (rightskip, right_skip_par);
    ext_do_line_break(paragraph_dir,
                      pretolerance,
                      tracingparagraphs,
                      tolerance,
                      emergencystretch,
                      looseness,
                      adjustspacing,
                      parshape,
                      adjdemerits,
                      protrudechars,
                      linepenalty,
                      lastlinefit,
                      doublehyphendemerits,
                      finalhyphendemerits,
                      hangindent,
                      hsize,
                      hangafter,
                      leftskip,
                      rightskip,
                      interlinepenalties,
                      interlinepenalty,
                      clubpenalty,
                      clubpenalties,
                      widowpenalties,
                      widowpenalty,
                      brokenpenalty,
                      final_par_glue);

    /* return the generated list, and its prevdepth */
    get_linebreak_info (&fewest_demerits, &actual_looseness) ;
    lua_nodelib_push_fast(L, vlink(cur_list.head_field));
    lua_newtable(L);
    lua_push_key(demerits);
    lua_pushinteger(L, fewest_demerits);
    lua_settable(L, -3);
    lua_push_key(looseness);
    lua_pushinteger(L, actual_looseness);
    lua_settable(L, -3);
    lua_push_key(prevdepth);
    lua_pushinteger(L, cur_list.prev_depth_field);
    lua_settable(L, -3);
    lua_push_key(prevgraf);
    lua_pushinteger(L, cur_list.pg_field);
    lua_settable(L, -3);

    /* restore nest stack */
    vlink(temp_head) = save_vlink_tmp_head;
    pop_nest();
    if (parshape != equiv(par_shape_loc))
        flush_node(parshape);
    return 2;
}

static int tex_reset_paragraph(lua_State * L)
{
    (void) L;
    normal_paragraph();
    return 0;
}

static int tex_shipout(lua_State * L)
{
    int boxnum = get_box_id(L, 1, true);
    ship_out(static_pdf, box(boxnum), SHIPPING_PAGE);
    box(boxnum) = null;
    return 0;
}

static int tex_badness(lua_State * L)
{
    scaled t = lua_tointeger(L,1);
    scaled s = lua_tointeger(L,2);
    lua_pushinteger(L, badness(t,s));
    return 1;
}

static int tex_run_boot(lua_State * L)
{
    int n = lua_gettop(L);
    const char *format = NULL;
    if (n >= 1) {
        ini_version = 0;
        format = luaL_checkstring(L, 1);
    } else {
        ini_version = 1;
    }
    if (main_initialize()) {    /* > 0 = failure */
        lua_pushboolean(L, 0);  /* false */
        return 1;
    }
    if (format) {
        if (!zopen_w_input(&fmt_file, format, DUMP_FORMAT, FOPEN_RBIN_MODE)) {
            lua_pushboolean(L, 0);      /* false */
            return 1;
        }
        if (!load_fmt_file(format)) {
            zwclose(fmt_file);
            lua_pushboolean(L, 0);      /* false */
            return 1;
        }
        zwclose(fmt_file);
    }
    pdf_init_map_file("pdftex.map");
    /* */
    if (end_line_char_inactive)
        decr(ilimit);
    else
        buffer[ilimit] = (packed_ASCII_code) end_line_char_par;
    fix_date_and_time();
    random_seed = (microseconds * 1000) + (epochseconds % 1000000);
    init_randoms(random_seed);
    initialize_math();
    fixup_selector(log_opened_global);
    check_texconfig_init();
    text_dir_ptr = new_dir(0);
    history = spotless;         /* ready to go! */
    /* Initialize synctex primitive */
    synctexinitcommand();
    /* tex is ready to go, now */
    /*
    unhide_lua_table(Luas, "tex", tex_table_id);
    unhide_lua_table(Luas, "pdf", pdf_table_id);
    unhide_lua_table(Luas, "token", token_table_id);
    unhide_lua_table(Luas, "node", node_table_id);
    */
    lua_pushboolean(L, 1);      /* true */
    return 1;
}

/* tex random generators */

static int tex_init_rand(lua_State * L)
{
    int sp;
    if (lua_type(L, 1) != LUA_TNUMBER) {
        luaL_error(L, "argument must be a number");
        return 0;
    }
    sp = lua_roundnumber(L, 1);
    init_randoms(sp);
    return 0;
}

static int tex_unif_rand(lua_State * L)
{
    int sp;
    if (lua_type(L, 1) != LUA_TNUMBER) {
        luaL_error(L, "argument must be a number");
        return 0;
    }
    sp = lua_roundnumber(L, 1);
    lua_pushinteger(L, unif_rand(sp));
    return 1;
}

static int tex_norm_rand(lua_State * L)
{
    lua_pushinteger(L, norm_rand());
    return 1;
}

/* Same as lua but  with tex rng */

static int lua_math_random (lua_State *L)
{
    lua_Number rand_max = 0x7fffffff ;
    lua_Number r =  unif_rand(rand_max) ;
    r = (r>=0 ? 0+r : 0-r) ;
    r = r / rand_max;
    switch (lua_gettop(L)) {  /* check number of arguments */
        case 0: {  /* no arguments */
            lua_pushnumber(L, r);  /* float: [0, 1] */
            break;
        }
        case 1: {  /* only upper limit */
            lua_Number u = luaL_checknumber(L, 1);
            luaL_argcheck(L, (lua_Number)1.0 <= u, 1, "interval is empty");
            lua_pushnumber(L, floor(r*u) + (lua_Number)(1.0)); /* float: [1, u] */
            break;
        }
        case 2: {  /* lower and upper limits */
            lua_Number l = luaL_checknumber(L, 1);
            lua_Number u = luaL_checknumber(L, 2);
            luaL_argcheck(L, l <= u, 2, "interval is empty");
            lua_pushnumber(L, floor(r*(u-l+1)) + l);  /* float: [l, u] */
            break;
        }
        default:
            return luaL_error(L, "wrong number of arguments");
    }
    return 1;
}

static int tex_run_main(lua_State * L)
{
    (void) L;
    main_control();
    return 0;
}

static int tex_run_end(lua_State * L)
{
    (void) L;
    final_cleanup();            /* prepare for death */
    close_files_and_terminate();
    do_final_end();
    return 0;
}

static int tex_show_context(lua_State * L)
{
    (void) L;
    show_context();
    return 0;
}

static int tex_save_box_resource(lua_State * L)
{
    halfword boxdata;
    int index = null;
    int attributes = null;
    int resources = null;
    int type = 0;
    int margin = pdf_xform_margin;
    boolean immediate = false;
    /* more or less same as scanner variant */
    if (lua_type(L,1) == LUA_TNUMBER) {
        halfword boxnumber = lua_tointeger(L,1);
        boxdata = box(boxnumber);
        box(boxnumber) = null;
    } else {
        boxdata = nodelist_from_lua(L,1);
        if (type(boxdata) != hlist_node && type(boxdata) != vlist_node) {
            normal_error("pdf backend", "xforms can only be used with a box or [h|v]list");
        }
    }
    if (boxdata == null) {
        normal_error("pdf backend", "xforms cannot be used with a void box or empty [h|v]list");
    }
    /* box attributes resources */
    if (lua_type(L,2) == LUA_TSTRING) {
        lua_pushvalue(L, 2);
        attributes = luaL_ref(L, LUA_REGISTRYINDEX);
    }
    if (lua_type(L,3) == LUA_TSTRING) {
        lua_pushvalue(L, 3);
        resources = luaL_ref(L, LUA_REGISTRYINDEX);
    }
    if (lua_type(L,4) == LUA_TBOOLEAN) {
        immediate = lua_toboolean(L, 4);
    }
    if (lua_type(L,5) == LUA_TNUMBER) {
        type = lua_tointeger(L, 5);
    }
    if (lua_type(L,6) == LUA_TNUMBER) {
        margin = lua_tointeger(L, 6);
    }
    static_pdf->xform_count++;
    index = pdf_create_obj(static_pdf, obj_type_xform, static_pdf->xform_count);
    set_obj_data_ptr(static_pdf, index, pdf_get_mem(static_pdf, pdfmem_xform_size));
    set_obj_xform_attr(static_pdf, index, null);
    set_obj_xform_attr_str(static_pdf, index, attributes);
    set_obj_xform_resources(static_pdf, index, null);
    set_obj_xform_resources_str(static_pdf, index, resources);
    set_obj_xform_box(static_pdf, index, (int) boxdata);
    set_obj_xform_width(static_pdf, index, width(boxdata));
    set_obj_xform_height(static_pdf, index, height(boxdata));
    set_obj_xform_depth(static_pdf, index, depth(boxdata));
    set_obj_xform_type(static_pdf, index, type);
    set_obj_xform_margin(static_pdf, index, margin);
    last_saved_box_index = index;
    lua_pushinteger(L, index);
    if (immediate) {
        pdf_cur_form = last_saved_box_index;
        ship_out(static_pdf, obj_xform_box(static_pdf, last_saved_box_index), SHIPPING_FORM);
    }
    return 1;
}

static int tex_use_box_resource(lua_State * L)
{
    halfword rule;
    int index = 0;
    scaled_whd alt, nat, dim;
    if (lua_type(L,1) != LUA_TNUMBER) {
        lua_pushnil(L);
        lua_pushnil(L);
        lua_pushnil(L);
        lua_pushnil(L);
    } else {
        index = lua_tointeger(L,1);
        alt.wd = null_flag;
        alt.ht = null_flag;
        alt.dp = null_flag;
        if (lua_type(L,2) == LUA_TNUMBER) {
            alt.wd = (scaled) lua_roundnumber(L,2);
        }
        if (lua_type(L,3) == LUA_TNUMBER) {
            alt.ht = (scaled) lua_roundnumber(L,3);
        }
        if (lua_type(L,4) == LUA_TNUMBER) {
            alt.dp = (scaled) lua_roundnumber(L,4);
        }
        /* sort of the same as backend */
        check_obj_type(static_pdf, obj_type_xform, index);
        nat.wd = obj_xform_width(static_pdf, index);
        nat.ht = obj_xform_height(static_pdf, index);
        nat.dp = obj_xform_depth(static_pdf, index);
        if (alt.wd != null_flag || alt.ht != null_flag || alt.dp != null_flag) {
            dim = tex_scale(nat, alt);
        } else {
            dim = nat;
        }
        rule = new_rule(box_rule);
        rule_index(rule) = index;
        width(rule) = dim.wd;
        height(rule) = dim.ht;
        depth(rule) = dim.dp;
        nodelist_to_lua(L, rule);
        lua_pushinteger(L, (int) dim.wd);
        lua_pushinteger(L, (int) dim.ht);
        lua_pushinteger(L, (int) dim.dp);
    }
    return 4;
}

static int tex_get_box_resource_dimensions(lua_State * L)
{
    int index = 0;
    if (lua_type(L,1) != LUA_TNUMBER) {
        lua_pushnil(L);
        lua_pushnil(L);
        lua_pushnil(L);
        lua_pushnil(L);
    } else {
        index = lua_tointeger(L,1);
        check_obj_type(static_pdf, obj_type_xform, index);
        lua_pushinteger(L, (int) obj_xform_width(static_pdf, index));
        lua_pushinteger(L, (int) obj_xform_height(static_pdf, index));
        lua_pushinteger(L, (int) obj_xform_depth(static_pdf, index));
        lua_pushinteger(L, (int) obj_xform_margin(static_pdf, index));
    }
    return 4;
}

static int tex_get_box_resource_box(lua_State * L)
{
    /* no checking yet as this might go */
    halfword b;
    int index = lua_tointeger(L,1);
    check_obj_type(static_pdf, obj_type_xform, index);
    b = obj_xform_box(static_pdf, index);
    nodelist_to_lua(L, b);
    return 1;
}

static int tex_build_page(lua_State * L)
{
    build_page();
    return 0;
}

static int lua_get_page_state(lua_State * L)
{
    lua_pushinteger(L,page_contents);
    return 1;
}

static int lua_get_local_level(lua_State * L)
{
    lua_pushinteger(L,current_local_level());
    return 1;
}

/* synctex */

static int lua_set_synctex_mode(lua_State * L)
{
    halfword mode = lua_tointeger(L, 1);
    synctex_set_mode(mode);
    return 0;
}
static int lua_get_synctex_mode(lua_State * L)
{
    lua_pushinteger(L,synctex_get_mode());
    return 1;
}

static int lua_set_synctex_tag(lua_State * L)
{
    halfword tag = lua_tointeger(L, 1);
    synctex_set_tag(tag);
    return 0;
}

static int lua_get_synctex_tag(lua_State * L)
{
    lua_pushinteger(L,synctex_get_tag());
    return 1;
}

static int lua_force_synctex_tag(lua_State * L)
{
    halfword tag = lua_tointeger(L, 1);
    synctex_force_tag(tag);
    return 0;
}

static int lua_force_synctex_line(lua_State * L)
{
    halfword line = lua_tointeger(L, 1);
    synctex_force_line(line);
    return 0;
}

static int lua_set_synctex_line(lua_State * L)
{
    halfword line = lua_tointeger(L, 1);
    synctex_set_line(line);
    return 0;
}

static int lua_get_synctex_line(lua_State * L)
{
    lua_pushinteger(L,synctex_get_line());
    return 1;
}

static int lua_set_synctex_no_files(lua_State * L)
{
    halfword flag = lua_tointeger(L, 1);
    synctex_set_no_files(flag);
    return 0;
}

/*
    This is experimental and might change. In version 10 we hope to have the
    final version available. It actually took quite a bit of time to understand
    the implications of mixing lua prints in here. The current variant is (so far)
    the most robust (wrt crashes and side effects).
*/

#define mode mode_par

/*
    When we add save levels then we can get crashes when one flushed bad
    groups due to out of order flushing. So we play safe! But still we can
    have issues so best make sure you're in hmode.
*/

static int forcehmode(lua_State * L)
{
    if (abs(mode) == vmode) {
        if (lua_type(L,1) == LUA_TBOOLEAN) {
            new_graf(lua_toboolean(L,1));
        } else {
            new_graf(1);
        }
    }
    return 0;
}

static int runtoks(lua_State * L)
{
    if (lua_type(L,1) == LUA_TFUNCTION) {
        int old_mode = mode;
        int ref;
        halfword r = get_avail();
        halfword t = get_avail();
        token_info(r) = token_val(extension_cmd,end_local_code);
        lua_pushvalue(L, 1);
        ref = luaL_ref(L,LUA_REGISTRYINDEX);
        token_info(t) = token_val(lua_local_call_cmd, ref);
        begin_token_list(r,inserted);
        begin_token_list(t,inserted);
        if (luacstrings > 0) {
            lua_string_start();
        }
        if (tracing_nesting_par > 2) {
            local_control_message("entering token scanner via function");
        }
        mode = -hmode;
        local_control();
        mode = old_mode;
        luaL_unref(L,LUA_REGISTRYINDEX,ref);
    } else {
        halfword t;
        int k = get_item_index(L, 1, toks_base);
        check_index_range(k, "gettoks");
        t = toks(k);
        if (! t) {
            /* nothing to do */
        } else if ((scanner_status != defining) || (lua_toboolean(L,2))) {
            int grouped = lua_toboolean(L,3);
            int old_mode = mode;
            if (grouped) {
                halfword r = get_avail();
                token_info(r) = token_val(right_brace_cmd,0);
                begin_token_list(r,inserted);
            }
            {
                halfword r = get_avail();
                token_info(r) = token_val(extension_cmd,end_local_code);
                begin_token_list(r,inserted);
            }
            begin_token_list(t,local_text);
            if (grouped) {
                halfword r = get_avail();
                token_info(r) = token_val(left_brace_cmd,0);
                begin_token_list(r,inserted);
            }
            if (luacstrings > 0) {
                lua_string_start();
            }
            if (tracing_nesting_par > 2) {
                local_control_message("entering token scanner via register");
            }
            mode = -hmode;
            local_control();
            mode = old_mode;
            /* unsave(); */
        } else {
            halfword q;
            halfword p = temp_token_head;
            halfword r = token_link(t);
            set_token_link(p, null);
            while (r) {
                fast_store_new_token(token_info(r));
                r = token_link(r);
            }
            ins_list(token_link(temp_token_head));
        }
    }
    return 0;
}

static int quittoks(lua_State * L)
{
    (void) L;
    if (tracing_nesting_par > 2) {
        local_control_message("quitting token scanner");
    }
    end_local_control();
    return 0;
}

/*tex Negative values are internal and inline. */

static int tex_getmodevalues(lua_State * L)
{
    lua_newtable(L);
    lua_pushinteger(L,0);
    lua_push_string_by_name(L,unset);      /* 0 */
    lua_rawset(L, -3);
    lua_pushinteger(L,vmode);
    lua_push_string_by_name(L,vertical);   /* 1 */
    lua_rawset(L, -3);
    lua_pushinteger(L,hmode);
    lua_push_string_by_name(L,horizontal); /* 127 */
    lua_rawset(L, -3);
    lua_pushinteger(L,mmode);
    lua_push_string_by_name(L,math);       /* 253 */
    lua_rawset(L, -3);
    return 1;
}

/* till here */

void init_tex_table(lua_State * L)
{
    lua_createtable(L, 0, 3);
    lua_pushcfunction(L, tex_run_boot);
    lua_setfield(L, -2, "initialize");
    lua_pushcfunction(L, tex_run_main);
    lua_setfield(L, -2, "run");
    lua_pushcfunction(L, tex_run_end);
    lua_setfield(L, -2, "finish");
    lua_setglobal(L, "tex");
}

static const struct luaL_Reg texlib[] = {
    { "run", tex_run_main },      /* may be needed  */
    { "finish", tex_run_end },    /* may be needed  */
    { "write", luacwrite },
    { "print", luacprint },
    { "sprint", luacsprint },
    { "tprint", luactprint },
    { "cprint", luaccprint },
    /*
    { "twrite", luatwrite },
    { "nwrite", luanwrite },
    */
    { "error", texerror },
    { "set", settex },
    { "get", gettex },
    { "isdimen", isdimen },
    { "setdimen", setdimen },
    { "getdimen", getdimen },
    { "isskip", isskip },
    { "setskip", setskip },
    { "getskip", getskip },
    { "isglue", isskip },
    { "setglue", setglue },
    { "getglue", getglue },
    { "ismuskip", ismuskip },
    { "setmuskip", setmuskip },
    { "getmuskip", getmuskip },
    { "ismuglue", ismuskip },
    { "setmuglue", setmuglue },
    { "getmuglue", getmuglue },
    { "isattribute", isattribute },
    { "setattribute", setattribute },
    { "getattribute", getattribute },
    { "iscount", iscount },
    { "setcount", setcount },
    { "getcount", getcount },
    { "istoks", istoks },
    { "settoks", settoks },
    { "scantoks", scantoks },
    { "gettoks", gettoks },
    { "isbox", isbox },
    { "setbox", setbox },
    { "getbox", getbox },
    { "splitbox", splitbox },
    { "setlist", setlist },
    { "getlist", getlist },
    { "setnest", setnest }, /* only a message */
    { "getnest", getnest },
    { "setcatcode", setcatcode },
    { "getcatcode", getcatcode },
    { "setdelcode", setdelcode },
    { "getdelcode", getdelcode },
    { "getdelcodes", getdelcodes },
    { "setlccode", setlccode },
    { "getlccode", getlccode },
    { "setmathcode", setmathcode },
    { "getmathcode", getmathcode },
    { "getmathcodes", getmathcodes },
    { "setsfcode", setsfcode },
    { "getsfcode", getsfcode },
    { "setuccode", setuccode },
    { "getuccode", getuccode },
    { "round", tex_roundnumber },
    { "scale", tex_scaletable },
    { "sp", tex_scaledimen },
    { "fontname", getfontname },
    { "fontidentifier", getfontidentifier },
    { "uniformdeviate", getuniformdeviate },
    { "number", getnumber },
    { "romannumeral", getromannumeral },
    { "definefont", tex_definefont },
    { "hashtokens", tex_hashpairs },
    { "primitives", tex_primitives },
    { "extraprimitives", tex_extraprimitives },
    { "enableprimitives", tex_enableprimitives },
    { "shipout", tex_shipout },
    { "badness", tex_badness },
    { "setmath", tex_setmathparm },
    { "getmath", tex_getmathparm },
    { "linebreak", tex_run_linebreak },
    { "resetparagraph", tex_reset_paragraph },
    /* tex random generators     */
    { "init_rand",   tex_init_rand },
    { "uniform_rand",tex_unif_rand },
    { "normal_rand", tex_norm_rand },
    { "lua_math_randomseed", tex_init_rand }, /* syntactic sugar  */
    { "lua_math_random", lua_math_random },
    { "show_context", tex_show_context },
    { "saveboxresource", tex_save_box_resource },
    { "useboxresource", tex_use_box_resource },
    { "getboxresourcedimensions", tex_get_box_resource_dimensions },
    /* might go, used when sanitizing backend */
    { "getboxresourcebox", tex_get_box_resource_box },
    /* just for testing: it will probably stay but maybe with options */
    { "triggerbuildpage", tex_build_page },
    { "getpagestate", lua_get_page_state },
    { "getlocallevel", lua_get_local_level },
    /* not the best place but better than in node */
    { "set_synctex_mode", lua_set_synctex_mode },
    { "get_synctex_mode", lua_get_synctex_mode },
    { "set_synctex_tag", lua_set_synctex_tag },
    { "get_synctex_tag", lua_get_synctex_tag },
    { "set_synctex_no_files", lua_set_synctex_no_files },
    { "force_synctex_tag", lua_force_synctex_tag },
    { "force_synctex_line", lua_force_synctex_line },
    { "set_synctex_line", lua_set_synctex_line },
    { "get_synctex_line", lua_get_synctex_line },
    /* test */
    { "runtoks", runtoks },
    { "quittoks", quittoks },
    { "forcehmode", forcehmode },
    { "getmodevalues", tex_getmodevalues },
    /* sentinel */
    { NULL, NULL }
};

int luaopen_tex(lua_State * L)
{
    luaL_openlib(L, "tex", texlib, 0);
    /* *INDENT-OFF* */
    make_table(L, "attribute", "tex.attribute", "getattribute", "setattribute");
    make_table(L, "skip",      "tex.skip",      "getskip",      "setskip");
    make_table(L, "glue",      "tex.glue",      "getglue",      "setglue");
    make_table(L, "muskip",    "tex.muskip",    "getmuskip",    "setmuskip");
    make_table(L, "muglue",    "tex.muglue",    "getmuglue",    "setmuglue");
    make_table(L, "dimen",     "tex.dimen",     "getdimen",     "setdimen");
    make_table(L, "count",     "tex.count",     "getcount",     "setcount");
    make_table(L, "toks",      "tex.toks",      "gettoks",      "settoks");
    make_table(L, "box",       "tex.box",       "getbox",       "setbox");
    make_table(L, "sfcode",    "tex.sfcode",    "getsfcode",    "setsfcode");
    make_table(L, "lccode",    "tex.lccode",    "getlccode",    "setlccode");
    make_table(L, "uccode",    "tex.uccode",    "getuccode",    "setuccode");
    make_table(L, "catcode",   "tex.catcode",   "getcatcode",   "setcatcode");
    make_table(L, "mathcode",  "tex.mathcode",  "getmathcode",  "setmathcode");
    make_table(L, "delcode",   "tex.delcode",   "getdelcode",   "setdelcode");
    make_table(L, "lists",     "tex.lists",     "getlist",      "setlist");
    make_table(L, "nest",      "tex.nest",      "getnest",      "setnest");
    /* *INDENT-ON* */
    init_nest_lib(L);
    /* make the meta entries */
    /* fetch it back */
    luaL_newmetatable(L, "tex.meta");
    lua_pushstring(L, "__index");
    lua_pushcfunction(L, gettex);
    lua_settable(L, -3);
    lua_pushstring(L, "__newindex");
    lua_pushcfunction(L, settex);
    lua_settable(L, -3);
    lua_setmetatable(L, -2);    /* meta to itself */
    /* initialize the I/O stack: */
    spindles = xmalloc(sizeof(spindle));
    spindle_index = 0;
    spindles[0].head = NULL;
    spindles[0].tail = NULL;
    spindle_size = 1;
    /* a somewhat odd place for this assert, maybe */
    if (command_names[data_cmd].id != data_cmd) {
        fatal_error("mismatch between tex and lua command name tables");
    };
    return 1;
}
