add support for local variable declared with attribute 'close' and 'const' for Lua 5.4.

1 files changed, 285 insertions, 0 deletions

diff --git a/src/lua/lstring.c b/src/lua/lstring.c
new file mode 100644
index 0000000..6f15747
--- /dev/null
+++ b/src/lua/lstring.c
@@ -0,0 +1,285 @@
+/*
+** $Id: lstring.c $
+** String table (keeps all strings handled by Lua)
+** See Copyright Notice in lua.h
+*/
+
+#define lstring_c
+#define LUA_CORE
+
+#include "lprefix.h"
+
+
+#include <string.h>
+
+#include "lua.h"
+
+#include "ldebug.h"
+#include "ldo.h"
+#include "lmem.h"
+#include "lobject.h"
+#include "lstate.h"
+#include "lstring.h"
+
+
+/*
+** Lua will use at most ~(2^LUAI_HASHLIMIT) bytes from a long string to
+** compute its hash
+*/
+#if !defined(LUAI_HASHLIMIT)
+#define LUAI_HASHLIMIT          5
+#endif
+
+
+
+/*
+** Maximum size for string table.
+*/
+#define MAXSTRTB        cast_int(luaM_limitN(MAX_INT, TString*))
+
+
+/*
+** equality for long strings
+*/
+int luaS_eqlngstr (TString *a, TString *b) {
+  size_t len = a->u.lnglen;
+  lua_assert(a->tt == LUA_VLNGSTR && b->tt == LUA_VLNGSTR);
+  return (a == b) ||  /* same instance or... */
+    ((len == b->u.lnglen) &&  /* equal length and ... */
+     (memcmp(getstr(a), getstr(b), len) == 0));  /* equal contents */
+}
+
+
+unsigned int luaS_hash (const char *str, size_t l, unsigned int seed,
+                        size_t step) {
+  unsigned int h = seed ^ cast_uint(l);
+  for (; l >= step; l -= step)
+    h ^= ((h<<5) + (h>>2) + cast_byte(str[l - 1]));
+  return h;
+}
+
+
+unsigned int luaS_hashlongstr (TString *ts) {
+  lua_assert(ts->tt == LUA_VLNGSTR);
+  if (ts->extra == 0) {  /* no hash? */
+    size_t len = ts->u.lnglen;
+    size_t step = (len >> LUAI_HASHLIMIT) + 1;
+    ts->hash = luaS_hash(getstr(ts), len, ts->hash, step);
+    ts->extra = 1;  /* now it has its hash */
+  }
+  return ts->hash;
+}
+
+
+static void tablerehash (TString **vect, int osize, int nsize) {
+  int i;
+  for (i = osize; i < nsize; i++)  /* clear new elements */
+    vect[i] = NULL;
+  for (i = 0; i < osize; i++) {  /* rehash old part of the array */
+    TString *p = vect[i];
+    vect[i] = NULL;
+    while (p) {  /* for each string in the list */
+      TString *hnext = p->u.hnext;  /* save next */
+      unsigned int h = lmod(p->hash, nsize);  /* new position */
+      p->u.hnext = vect[h];  /* chain it into array */
+      vect[h] = p;
+      p = hnext;
+    }
+  }
+}
+
+
+/*
+** Resize the string table. If allocation fails, keep the current size.
+** (This can degrade performance, but any non-zero size should work
+** correctly.)
+*/
+void luaS_resize (lua_State *L, int nsize) {
+  stringtable *tb = &G(L)->strt;
+  int osize = tb->size;
+  TString **newvect;
+  if (nsize < osize)  /* shrinking table? */
+    tablerehash(tb->hash, osize, nsize);  /* depopulate shrinking part */
+  newvect = luaM_reallocvector(L, tb->hash, osize, nsize, TString*);
+  if (unlikely(newvect == NULL)) {  /* reallocation failed? */
+    if (nsize < osize)  /* was it shrinking table? */
+      tablerehash(tb->hash, nsize, osize);  /* restore to original size */
+    /* leave table as it was */
+  }
+  else {  /* allocation succeeded */
+    tb->hash = newvect;
+    tb->size = nsize;
+    if (nsize > osize)
+      tablerehash(newvect, osize, nsize);  /* rehash for new size */
+  }
+}
+
+
+/*
+** Clear API string cache. (Entries cannot be empty, so fill them with
+** a non-collectable string.)
+*/
+void luaS_clearcache (global_State *g) {
+  int i, j;
+  for (i = 0; i < STRCACHE_N; i++)
+    for (j = 0; j < STRCACHE_M; j++) {
+      if (iswhite(g->strcache[i][j]))  /* will entry be collected? */
+        g->strcache[i][j] = g->memerrmsg;  /* replace it with something fixed */
+    }
+}
+
+
+/*
+** Initialize the string table and the string cache
+*/
+void luaS_init (lua_State *L) {
+  global_State *g = G(L);
+  int i, j;
+  stringtable *tb = &G(L)->strt;
+  tb->hash = luaM_newvector(L, MINSTRTABSIZE, TString*);
+  tablerehash(tb->hash, 0, MINSTRTABSIZE);  /* clear array */
+  tb->size = MINSTRTABSIZE;
+  /* pre-create memory-error message */
+  g->memerrmsg = luaS_newliteral(L, MEMERRMSG);
+  luaC_fix(L, obj2gco(g->memerrmsg));  /* it should never be collected */
+  for (i = 0; i < STRCACHE_N; i++)  /* fill cache with valid strings */
+    for (j = 0; j < STRCACHE_M; j++)
+      g->strcache[i][j] = g->memerrmsg;
+}
+
+
+
+/*
+** creates a new string object
+*/
+static TString *createstrobj (lua_State *L, size_t l, int tag, unsigned int h) {
+  TString *ts;
+  GCObject *o;
+  size_t totalsize;  /* total size of TString object */
+  totalsize = sizelstring(l);
+  o = luaC_newobj(L, tag, totalsize);
+  ts = gco2ts(o);
+  ts->hash = h;
+  ts->extra = 0;
+  getstr(ts)[l] = '\0';  /* ending 0 */
+  return ts;
+}
+
+
+TString *luaS_createlngstrobj (lua_State *L, size_t l) {
+  TString *ts = createstrobj(L, l, LUA_VLNGSTR, G(L)->seed);
+  ts->u.lnglen = l;
+  return ts;
+}
+
+
+void luaS_remove (lua_State *L, TString *ts) {
+  stringtable *tb = &G(L)->strt;
+  TString **p = &tb->hash[lmod(ts->hash, tb->size)];
+  while (*p != ts)  /* find previous element */
+    p = &(*p)->u.hnext;
+  *p = (*p)->u.hnext;  /* remove element from its list */
+  tb->nuse--;
+}
+
+
+static void growstrtab (lua_State *L, stringtable *tb) {
+  if (unlikely(tb->nuse == MAX_INT)) {  /* too many strings? */
+    luaC_fullgc(L, 1);  /* try to free some... */
+    if (tb->nuse == MAX_INT)  /* still too many? */
+      luaM_error(L);  /* cannot even create a message... */
+  }
+  if (tb->size <= MAXSTRTB / 2)  /* can grow string table? */
+    luaS_resize(L, tb->size * 2);
+}
+
+
+/*
+** Checks whether short string exists and reuses it or creates a new one.
+*/
+static TString *internshrstr (lua_State *L, const char *str, size_t l) {
+  TString *ts;
+  global_State *g = G(L);
+  stringtable *tb = &g->strt;
+  unsigned int h = luaS_hash(str, l, g->seed, 1);
+  TString **list = &tb->hash[lmod(h, tb->size)];
+  lua_assert(str != NULL);  /* otherwise 'memcmp'/'memcpy' are undefined */
+  for (ts = *list; ts != NULL; ts = ts->u.hnext) {
+    if (l == ts->shrlen && (memcmp(str, getstr(ts), l * sizeof(char)) == 0)) {
+      /* found! */
+      if (isdead(g, ts))  /* dead (but not collected yet)? */
+        changewhite(ts);  /* resurrect it */
+      return ts;
+    }
+  }
+  /* else must create a new string */
+  if (tb->nuse >= tb->size) {  /* need to grow string table? */
+    growstrtab(L, tb);
+    list = &tb->hash[lmod(h, tb->size)];  /* rehash with new size */
+  }
+  ts = createstrobj(L, l, LUA_VSHRSTR, h);
+  memcpy(getstr(ts), str, l * sizeof(char));
+  ts->shrlen = cast_byte(l);
+  ts->u.hnext = *list;
+  *list = ts;
+  tb->nuse++;
+  return ts;
+}
+
+
+/*
+** new string (with explicit length)
+*/
+TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {
+  if (l <= LUAI_MAXSHORTLEN)  /* short string? */
+    return internshrstr(L, str, l);
+  else {
+    TString *ts;
+    if (unlikely(l >= (MAX_SIZE - sizeof(TString))/sizeof(char)))
+      luaM_toobig(L);
+    ts = luaS_createlngstrobj(L, l);
+    memcpy(getstr(ts), str, l * sizeof(char));
+    return ts;
+  }
+}
+
+
+/*
+** Create or reuse a zero-terminated string, first checking in the
+** cache (using the string address as a key). The cache can contain
+** only zero-terminated strings, so it is safe to use 'strcmp' to
+** check hits.
+*/
+TString *luaS_new (lua_State *L, const char *str) {
+  unsigned int i = point2uint(str) % STRCACHE_N;  /* hash */
+  int j;
+  TString **p = G(L)->strcache[i];
+  for (j = 0; j < STRCACHE_M; j++) {
+    if (strcmp(str, getstr(p[j])) == 0)  /* hit? */
+      return p[j];  /* that is it */
+  }
+  /* normal route */
+  for (j = STRCACHE_M - 1; j > 0; j--)
+    p[j] = p[j - 1];  /* move out last element */
+  /* new element is first in the list */
+  p[0] = luaS_newlstr(L, str, strlen(str));
+  return p[0];
+}
+
+
+Udata *luaS_newudata (lua_State *L, size_t s, int nuvalue) {
+  Udata *u;
+  int i;
+  GCObject *o;
+  if (unlikely(s > MAX_SIZE - udatamemoffset(nuvalue)))
+    luaM_toobig(L);
+  o = luaC_newobj(L, LUA_VUSERDATA, sizeudata(nuvalue, s));
+  u = gco2u(o);
+  u->len = s;
+  u->nuvalue = nuvalue;
+  u->metatable = NULL;
+  for (i = 0; i < nuvalue; i++)
+    setnilvalue(&u->uv[i].uv);
+  return u;
+}
+