diff options
author | 2015-01-13 17:59:12 +0100 | |
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committer | 2015-01-13 17:59:12 +0100 | |
commit | d60dc40fe37bbc90eecea9c0ebb1f932df38ab0b (patch) | |
tree | 34ba59a47662984394b88249db7c8103b05793c2 /3rdparty/lua/src/ltable.c | |
parent | b1876ae1a347c07d176bcb381d4ef54fcbd897c7 (diff) |
Update to Lua 5.3
Diffstat (limited to '3rdparty/lua/src/ltable.c')
-rw-r--r-- | 3rdparty/lua/src/ltable.c | 340 |
1 files changed, 201 insertions, 139 deletions
diff --git a/3rdparty/lua/src/ltable.c b/3rdparty/lua/src/ltable.c index 5d76f97ec3c..38be00513dc 100644 --- a/3rdparty/lua/src/ltable.c +++ b/3rdparty/lua/src/ltable.c @@ -1,27 +1,32 @@ /* -** $Id: ltable.c,v 2.72.1.1 2013/04/12 18:48:47 roberto Exp $ +** $Id: ltable.c,v 2.100 2015/01/05 13:52:37 roberto Exp $ ** Lua tables (hash) ** See Copyright Notice in lua.h */ +#define ltable_c +#define LUA_CORE + +#include "lprefix.h" + /* ** Implementation of tables (aka arrays, objects, or hash tables). ** Tables keep its elements in two parts: an array part and a hash part. ** Non-negative integer keys are all candidates to be kept in the array -** part. The actual size of the array is the largest `n' such that at +** part. The actual size of the array is the largest 'n' such that at ** least half the slots between 0 and n are in use. ** Hash uses a mix of chained scatter table with Brent's variation. ** A main invariant of these tables is that, if an element is not -** in its main position (i.e. the `original' position that its hash gives +** in its main position (i.e. the 'original' position that its hash gives ** to it), then the colliding element is in its own main position. ** Hence even when the load factor reaches 100%, performance remains good. */ +#include <float.h> +#include <math.h> #include <string.h> - -#define ltable_c -#define LUA_CORE +#include <limits.h> #include "lua.h" @@ -37,21 +42,26 @@ /* -** max size of array part is 2^MAXBITS +** Maximum size of array part (MAXASIZE) is 2^MAXABITS. MAXABITS is +** the largest integer such that MAXASIZE fits in an unsigned int. */ -#if LUAI_BITSINT >= 32 -#define MAXBITS 30 -#else -#define MAXBITS (LUAI_BITSINT-2) -#endif +#define MAXABITS cast_int(sizeof(int) * CHAR_BIT - 1) +#define MAXASIZE (1u << MAXABITS) -#define MAXASIZE (1 << MAXBITS) +/* +** Maximum size of hash part is 2^MAXHBITS. MAXHBITS is the largest +** integer such that 2^MAXHBITS fits in a signed int. (Note that the +** maximum number of elements in a table, 2^MAXABITS + 2^MAXHBITS, still +** fits comfortably in an unsigned int.) +*/ +#define MAXHBITS (MAXABITS - 1) #define hashpow2(t,n) (gnode(t, lmod((n), sizenode(t)))) -#define hashstr(t,str) hashpow2(t, (str)->tsv.hash) +#define hashstr(t,str) hashpow2(t, (str)->hash) #define hashboolean(t,p) hashpow2(t, p) +#define hashint(t,i) hashpow2(t, i) /* @@ -61,7 +71,7 @@ #define hashmod(t,n) (gnode(t, ((n) % ((sizenode(t)-1)|1)))) -#define hashpointer(t,p) hashmod(t, IntPoint(p)) +#define hashpointer(t,p) hashmod(t, point2int(p)) #define dummynode (&dummynode_) @@ -70,16 +80,28 @@ static const Node dummynode_ = { {NILCONSTANT}, /* value */ - {{NILCONSTANT, NULL}} /* key */ + {{NILCONSTANT, 0}} /* key */ }; /* -** hash for lua_Numbers +** Checks whether a float has a value representable as a lua_Integer +** (and does the conversion if so) +*/ +static int numisinteger (lua_Number x, lua_Integer *p) { + if ((x) == l_floor(x)) /* integral value? */ + return lua_numbertointeger(x, p); /* try as an integer */ + else return 0; +} + + +/* +** hash for floating-point numbers */ -static Node *hashnum (const Table *t, lua_Number n) { +static Node *hashfloat (const Table *t, lua_Number n) { int i; - luai_hashnum(i, n); + n = l_mathop(frexp)(n, &i) * cast_num(INT_MAX - DBL_MAX_EXP); + i += cast_int(n); if (i < 0) { if (cast(unsigned int, i) == 0u - i) /* use unsigned to avoid overflows */ i = 0; /* handle INT_MIN */ @@ -91,23 +113,25 @@ static Node *hashnum (const Table *t, lua_Number n) { /* -** returns the `main' position of an element in a table (that is, the index +** returns the 'main' position of an element in a table (that is, the index ** of its hash value) */ static Node *mainposition (const Table *t, const TValue *key) { switch (ttype(key)) { - case LUA_TNUMBER: - return hashnum(t, nvalue(key)); + case LUA_TNUMINT: + return hashint(t, ivalue(key)); + case LUA_TNUMFLT: + return hashfloat(t, fltvalue(key)); + case LUA_TSHRSTR: + return hashstr(t, tsvalue(key)); case LUA_TLNGSTR: { - TString *s = rawtsvalue(key); - if (s->tsv.extra == 0) { /* no hash? */ - s->tsv.hash = luaS_hash(getstr(s), s->tsv.len, s->tsv.hash); - s->tsv.extra = 1; /* now it has its hash */ + TString *s = tsvalue(key); + if (s->extra == 0) { /* no hash? */ + s->hash = luaS_hash(getstr(s), s->len, s->hash); + s->extra = 1; /* now it has its hash */ } - return hashstr(t, rawtsvalue(key)); + return hashstr(t, tsvalue(key)); } - case LUA_TSHRSTR: - return hashstr(t, rawtsvalue(key)); case LUA_TBOOLEAN: return hashboolean(t, bvalue(key)); case LUA_TLIGHTUSERDATA: @@ -121,61 +145,61 @@ static Node *mainposition (const Table *t, const TValue *key) { /* -** returns the index for `key' if `key' is an appropriate key to live in -** the array part of the table, -1 otherwise. +** returns the index for 'key' if 'key' is an appropriate key to live in +** the array part of the table, 0 otherwise. */ -static int arrayindex (const TValue *key) { - if (ttisnumber(key)) { - lua_Number n = nvalue(key); - int k; - lua_number2int(k, n); - if (luai_numeq(cast_num(k), n)) - return k; +static unsigned int arrayindex (const TValue *key) { + if (ttisinteger(key)) { + lua_Integer k = ivalue(key); + if (0 < k && (lua_Unsigned)k <= MAXASIZE) + return cast(unsigned int, k); /* 'key' is an appropriate array index */ } - return -1; /* `key' did not match some condition */ + return 0; /* 'key' did not match some condition */ } /* -** returns the index of a `key' for table traversals. First goes all +** returns the index of a 'key' for table traversals. First goes all ** elements in the array part, then elements in the hash part. The -** beginning of a traversal is signaled by -1. +** beginning of a traversal is signaled by 0. */ -static int findindex (lua_State *L, Table *t, StkId key) { - int i; - if (ttisnil(key)) return -1; /* first iteration */ +static unsigned int findindex (lua_State *L, Table *t, StkId key) { + unsigned int i; + if (ttisnil(key)) return 0; /* first iteration */ i = arrayindex(key); - if (0 < i && i <= t->sizearray) /* is `key' inside array part? */ - return i-1; /* yes; that's the index (corrected to C) */ + if (i != 0 && i <= t->sizearray) /* is 'key' inside array part? */ + return i; /* yes; that's the index */ else { + int nx; Node *n = mainposition(t, key); - for (;;) { /* check whether `key' is somewhere in the chain */ - /* key may be dead already, but it is ok to use it in `next' */ + for (;;) { /* check whether 'key' is somewhere in the chain */ + /* key may be dead already, but it is ok to use it in 'next' */ if (luaV_rawequalobj(gkey(n), key) || (ttisdeadkey(gkey(n)) && iscollectable(key) && deadvalue(gkey(n)) == gcvalue(key))) { i = cast_int(n - gnode(t, 0)); /* key index in hash table */ /* hash elements are numbered after array ones */ - return i + t->sizearray; + return (i + 1) + t->sizearray; } - else n = gnext(n); - if (n == NULL) - luaG_runerror(L, "invalid key to " LUA_QL("next")); /* key not found */ + nx = gnext(n); + if (nx == 0) + luaG_runerror(L, "invalid key to 'next'"); /* key not found */ + else n += nx; } } } int luaH_next (lua_State *L, Table *t, StkId key) { - int i = findindex(L, t, key); /* find original element */ - for (i++; i < t->sizearray; i++) { /* try first array part */ + unsigned int i = findindex(L, t, key); /* find original element */ + for (; i < t->sizearray; i++) { /* try first array part */ if (!ttisnil(&t->array[i])) { /* a non-nil value? */ - setnvalue(key, cast_num(i+1)); + setivalue(key, i + 1); setobj2s(L, key+1, &t->array[i]); return 1; } } - for (i -= t->sizearray; i < sizenode(t); i++) { /* then hash part */ + for (i -= t->sizearray; cast_int(i) < sizenode(t); i++) { /* hash part */ if (!ttisnil(gval(gnode(t, i)))) { /* a non-nil value? */ setobj2s(L, key, gkey(gnode(t, i))); setobj2s(L, key+1, gval(gnode(t, i))); @@ -192,19 +216,24 @@ int luaH_next (lua_State *L, Table *t, StkId key) { ** ============================================================== */ - -static int computesizes (int nums[], int *narray) { +/* +** Compute the optimal size for the array part of table 't'. 'nums' is a +** "count array" where 'nums[i]' is the number of integers in the table +** between 2^(i - 1) + 1 and 2^i. Put in '*narray' the optimal size, and +** return the number of elements that will go to that part. +*/ +static unsigned int computesizes (unsigned int nums[], unsigned int *narray) { int i; - int twotoi; /* 2^i */ - int a = 0; /* number of elements smaller than 2^i */ - int na = 0; /* number of elements to go to array part */ - int n = 0; /* optimal size for array part */ + unsigned int twotoi; /* 2^i */ + unsigned int a = 0; /* number of elements smaller than 2^i */ + unsigned int na = 0; /* number of elements to go to array part */ + unsigned int n = 0; /* optimal size for array part */ for (i = 0, twotoi = 1; twotoi/2 < *narray; i++, twotoi *= 2) { if (nums[i] > 0) { a += nums[i]; if (a > twotoi/2) { /* more than half elements present? */ n = twotoi; /* optimal size (till now) */ - na = a; /* all elements smaller than n will go to array part */ + na = a; /* all elements up to 'n' will go to array part */ } } if (a == *narray) break; /* all elements already counted */ @@ -215,9 +244,9 @@ static int computesizes (int nums[], int *narray) { } -static int countint (const TValue *key, int *nums) { - int k = arrayindex(key); - if (0 < k && k <= MAXASIZE) { /* is `key' an appropriate array index? */ +static int countint (const TValue *key, unsigned int *nums) { + unsigned int k = arrayindex(key); + if (k != 0) { /* is 'key' an appropriate array index? */ nums[luaO_ceillog2(k)]++; /* count as such */ return 1; } @@ -226,20 +255,21 @@ static int countint (const TValue *key, int *nums) { } -static int numusearray (const Table *t, int *nums) { +static unsigned int numusearray (const Table *t, unsigned int *nums) { int lg; - int ttlg; /* 2^lg */ - int ause = 0; /* summation of `nums' */ - int i = 1; /* count to traverse all array keys */ - for (lg=0, ttlg=1; lg<=MAXBITS; lg++, ttlg*=2) { /* for each slice */ - int lc = 0; /* counter */ - int lim = ttlg; + unsigned int ttlg; /* 2^lg */ + unsigned int ause = 0; /* summation of 'nums' */ + unsigned int i = 1; /* count to traverse all array keys */ + /* traverse each slice */ + for (lg = 0, ttlg = 1; lg <= MAXABITS; lg++, ttlg *= 2) { + unsigned int lc = 0; /* counter */ + unsigned int lim = ttlg; if (lim > t->sizearray) { lim = t->sizearray; /* adjust upper limit */ if (i > lim) break; /* no more elements to count */ } - /* count elements in range (2^(lg-1), 2^lg] */ + /* count elements in range (2^(lg - 1), 2^lg] */ for (; i <= lim; i++) { if (!ttisnil(&t->array[i-1])) lc++; @@ -251,9 +281,10 @@ static int numusearray (const Table *t, int *nums) { } -static int numusehash (const Table *t, int *nums, int *pnasize) { +static int numusehash (const Table *t, unsigned int *nums, + unsigned int *pnasize) { int totaluse = 0; /* total number of elements */ - int ause = 0; /* summation of `nums' */ + int ause = 0; /* elements added to 'nums' (can go to array part) */ int i = sizenode(t); while (i--) { Node *n = &t->node[i]; @@ -267,8 +298,8 @@ static int numusehash (const Table *t, int *nums, int *pnasize) { } -static void setarrayvector (lua_State *L, Table *t, int size) { - int i; +static void setarrayvector (lua_State *L, Table *t, unsigned int size) { + unsigned int i; luaM_reallocvector(L, t->array, t->sizearray, size, TValue); for (i=t->sizearray; i<size; i++) setnilvalue(&t->array[i]); @@ -276,23 +307,23 @@ static void setarrayvector (lua_State *L, Table *t, int size) { } -static void setnodevector (lua_State *L, Table *t, int size) { +static void setnodevector (lua_State *L, Table *t, unsigned int size) { int lsize; if (size == 0) { /* no elements to hash part? */ - t->node = cast(Node *, dummynode); /* use common `dummynode' */ + t->node = cast(Node *, dummynode); /* use common 'dummynode' */ lsize = 0; } else { int i; lsize = luaO_ceillog2(size); - if (lsize > MAXBITS) + if (lsize > MAXHBITS) luaG_runerror(L, "table overflow"); size = twoto(lsize); t->node = luaM_newvector(L, size, Node); - for (i=0; i<size; i++) { + for (i = 0; i < (int)size; i++) { Node *n = gnode(t, i); - gnext(n) = NULL; - setnilvalue(gkey(n)); + gnext(n) = 0; + setnilvalue(wgkey(n)); setnilvalue(gval(n)); } } @@ -301,9 +332,11 @@ static void setnodevector (lua_State *L, Table *t, int size) { } -void luaH_resize (lua_State *L, Table *t, int nasize, int nhsize) { - int i; - int oldasize = t->sizearray; +void luaH_resize (lua_State *L, Table *t, unsigned int nasize, + unsigned int nhsize) { + unsigned int i; + int j; + unsigned int oldasize = t->sizearray; int oldhsize = t->lsizenode; Node *nold = t->node; /* save old hash ... */ if (nasize > oldasize) /* array part must grow? */ @@ -321,8 +354,8 @@ void luaH_resize (lua_State *L, Table *t, int nasize, int nhsize) { luaM_reallocvector(L, t->array, oldasize, nasize, TValue); } /* re-insert elements from hash part */ - for (i = twoto(oldhsize) - 1; i >= 0; i--) { - Node *old = nold+i; + for (j = twoto(oldhsize) - 1; j >= 0; j--) { + Node *old = nold + j; if (!ttisnil(gval(old))) { /* doesn't need barrier/invalidate cache, as entry was already present in the table */ @@ -334,18 +367,20 @@ void luaH_resize (lua_State *L, Table *t, int nasize, int nhsize) { } -void luaH_resizearray (lua_State *L, Table *t, int nasize) { +void luaH_resizearray (lua_State *L, Table *t, unsigned int nasize) { int nsize = isdummy(t->node) ? 0 : sizenode(t); luaH_resize(L, t, nasize, nsize); } - +/* +** nums[i] = number of keys 'k' where 2^(i - 1) < k <= 2^i +*/ static void rehash (lua_State *L, Table *t, const TValue *ek) { - int nasize, na; - int nums[MAXBITS+1]; /* nums[i] = number of keys with 2^(i-1) < k <= 2^i */ + unsigned int nasize, na; + unsigned int nums[MAXABITS + 1]; int i; int totaluse; - for (i=0; i<=MAXBITS; i++) nums[i] = 0; /* reset counts */ + for (i = 0; i <= MAXABITS; i++) nums[i] = 0; /* reset counts */ nasize = numusearray(t, nums); /* count keys in array part */ totaluse = nasize; /* all those keys are integer keys */ totaluse += numusehash(t, nums, &nasize); /* count keys in hash part */ @@ -366,7 +401,8 @@ static void rehash (lua_State *L, Table *t, const TValue *ek) { Table *luaH_new (lua_State *L) { - Table *t = &luaC_newobj(L, LUA_TTABLE, sizeof(Table), NULL, 0)->h; + GCObject *o = luaC_newobj(L, LUA_TTABLE, sizeof(Table)); + Table *t = gco2t(o); t->metatable = NULL; t->flags = cast_byte(~0); t->array = NULL; @@ -404,37 +440,52 @@ static Node *getfreepos (Table *t) { */ TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) { Node *mp; + TValue aux; if (ttisnil(key)) luaG_runerror(L, "table index is nil"); - else if (ttisnumber(key) && luai_numisnan(L, nvalue(key))) - luaG_runerror(L, "table index is NaN"); + else if (ttisfloat(key)) { + lua_Number n = fltvalue(key); + lua_Integer k; + if (luai_numisnan(n)) + luaG_runerror(L, "table index is NaN"); + if (numisinteger(n, &k)) { /* index is int? */ + setivalue(&aux, k); + key = &aux; /* insert it as an integer */ + } + } mp = mainposition(t, key); if (!ttisnil(gval(mp)) || isdummy(mp)) { /* main position is taken? */ Node *othern; - Node *n = getfreepos(t); /* get a free place */ - if (n == NULL) { /* cannot find a free place? */ + Node *f = getfreepos(t); /* get a free place */ + if (f == NULL) { /* cannot find a free place? */ rehash(L, t, key); /* grow table */ - /* whatever called 'newkey' take care of TM cache and GC barrier */ + /* whatever called 'newkey' takes care of TM cache and GC barrier */ return luaH_set(L, t, key); /* insert key into grown table */ } - lua_assert(!isdummy(n)); + lua_assert(!isdummy(f)); othern = mainposition(t, gkey(mp)); if (othern != mp) { /* is colliding node out of its main position? */ /* yes; move colliding node into free position */ - while (gnext(othern) != mp) othern = gnext(othern); /* find previous */ - gnext(othern) = n; /* redo the chain with `n' in place of `mp' */ - *n = *mp; /* copy colliding node into free pos. (mp->next also goes) */ - gnext(mp) = NULL; /* now `mp' is free */ + while (othern + gnext(othern) != mp) /* find previous */ + othern += gnext(othern); + gnext(othern) = cast_int(f - othern); /* rechain to point to 'f' */ + *f = *mp; /* copy colliding node into free pos. (mp->next also goes) */ + if (gnext(mp) != 0) { + gnext(f) += cast_int(mp - f); /* correct 'next' */ + gnext(mp) = 0; /* now 'mp' is free */ + } setnilvalue(gval(mp)); } else { /* colliding node is in its own main position */ /* new node will go into free position */ - gnext(n) = gnext(mp); /* chain new position */ - gnext(mp) = n; - mp = n; + if (gnext(mp) != 0) + gnext(f) = cast_int((mp + gnext(mp)) - f); /* chain new position */ + else lua_assert(gnext(f) == 0); + gnext(mp) = cast_int(f - mp); + mp = f; } } - setobj2t(L, gkey(mp), key); - luaC_barrierback(L, obj2gco(t), key); + setnodekey(L, &mp->i_key, key); + luaC_barrierback(L, t, key); lua_assert(ttisnil(gval(mp))); return gval(mp); } @@ -443,18 +494,21 @@ TValue *luaH_newkey (lua_State *L, Table *t, const TValue *key) { /* ** search function for integers */ -const TValue *luaH_getint (Table *t, int key) { +const TValue *luaH_getint (Table *t, lua_Integer key) { /* (1 <= key && key <= t->sizearray) */ - if (cast(unsigned int, key-1) < cast(unsigned int, t->sizearray)) - return &t->array[key-1]; + if (l_castS2U(key - 1) < t->sizearray) + return &t->array[key - 1]; else { - lua_Number nk = cast_num(key); - Node *n = hashnum(t, nk); - do { /* check whether `key' is somewhere in the chain */ - if (ttisnumber(gkey(n)) && luai_numeq(nvalue(gkey(n)), nk)) + Node *n = hashint(t, key); + for (;;) { /* check whether 'key' is somewhere in the chain */ + if (ttisinteger(gkey(n)) && ivalue(gkey(n)) == key) return gval(n); /* that's it */ - else n = gnext(n); - } while (n); + else { + int nx = gnext(n); + if (nx == 0) break; + n += nx; + } + }; return luaO_nilobject; } } @@ -465,12 +519,17 @@ const TValue *luaH_getint (Table *t, int key) { */ const TValue *luaH_getstr (Table *t, TString *key) { Node *n = hashstr(t, key); - lua_assert(key->tsv.tt == LUA_TSHRSTR); - do { /* check whether `key' is somewhere in the chain */ - if (ttisshrstring(gkey(n)) && eqshrstr(rawtsvalue(gkey(n)), key)) + lua_assert(key->tt == LUA_TSHRSTR); + for (;;) { /* check whether 'key' is somewhere in the chain */ + const TValue *k = gkey(n); + if (ttisshrstring(k) && eqshrstr(tsvalue(k), key)) return gval(n); /* that's it */ - else n = gnext(n); - } while (n); + else { + int nx = gnext(n); + if (nx == 0) break; + n += nx; + } + }; return luaO_nilobject; } @@ -480,23 +539,26 @@ const TValue *luaH_getstr (Table *t, TString *key) { */ const TValue *luaH_get (Table *t, const TValue *key) { switch (ttype(key)) { - case LUA_TSHRSTR: return luaH_getstr(t, rawtsvalue(key)); + case LUA_TSHRSTR: return luaH_getstr(t, tsvalue(key)); + case LUA_TNUMINT: return luaH_getint(t, ivalue(key)); case LUA_TNIL: return luaO_nilobject; - case LUA_TNUMBER: { - int k; - lua_Number n = nvalue(key); - lua_number2int(k, n); - if (luai_numeq(cast_num(k), n)) /* index is int? */ + case LUA_TNUMFLT: { + lua_Integer k; + if (numisinteger(fltvalue(key), &k)) /* index is int? */ return luaH_getint(t, k); /* use specialized version */ /* else go through */ } default: { Node *n = mainposition(t, key); - do { /* check whether `key' is somewhere in the chain */ + for (;;) { /* check whether 'key' is somewhere in the chain */ if (luaV_rawequalobj(gkey(n), key)) return gval(n); /* that's it */ - else n = gnext(n); - } while (n); + else { + int nx = gnext(n); + if (nx == 0) break; + n += nx; + } + }; return luaO_nilobject; } } @@ -515,14 +577,14 @@ TValue *luaH_set (lua_State *L, Table *t, const TValue *key) { } -void luaH_setint (lua_State *L, Table *t, int key, TValue *value) { +void luaH_setint (lua_State *L, Table *t, lua_Integer key, TValue *value) { const TValue *p = luaH_getint(t, key); TValue *cell; if (p != luaO_nilobject) cell = cast(TValue *, p); else { TValue k; - setnvalue(&k, cast_num(key)); + setivalue(&k, key); cell = luaH_newkey(L, t, &k); } setobj2t(L, cell, value); @@ -532,16 +594,16 @@ void luaH_setint (lua_State *L, Table *t, int key, TValue *value) { static int unbound_search (Table *t, unsigned int j) { unsigned int i = j; /* i is zero or a present index */ j++; - /* find `i' and `j' such that i is present and j is not */ + /* find 'i' and 'j' such that i is present and j is not */ while (!ttisnil(luaH_getint(t, j))) { i = j; - j *= 2; - if (j > cast(unsigned int, MAX_INT)) { /* overflow? */ + if (j > cast(unsigned int, MAX_INT)/2) { /* overflow? */ /* table was built with bad purposes: resort to linear search */ i = 1; while (!ttisnil(luaH_getint(t, i))) i++; return i - 1; } + j *= 2; } /* now do a binary search between them */ while (j - i > 1) { @@ -554,7 +616,7 @@ static int unbound_search (Table *t, unsigned int j) { /* -** Try to find a boundary in table `t'. A `boundary' is an integer index +** Try to find a boundary in table 't'. A 'boundary' is an integer index ** such that t[i] is non-nil and t[i+1] is nil (and 0 if t[1] is nil). */ int luaH_getn (Table *t) { |