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authorlneto <lneto@NetBSD.org>2014-07-19 18:38:33 +0000
committerlneto <lneto@NetBSD.org>2014-07-19 18:38:33 +0000
commitc4b1eb35e827c43a0dcf41027c98aaedf46be036 (patch)
treef80015954e9c51266af4f2e1c57f2134cbcc1d62 /external/mit/lua/dist/src/lstring.c
parentc6d74635a1d93d95a3770bd621dcd83ed33100c2 (diff)
lua: updated from 5.1 to 5.3 work3
* lua(1): - changed lua_Integer to intmax_t - updated distrib/sets/lists and etc/mtree - updated bsd.lua.mk - fixed bozohttpd (lua-bozo.c) - compatibilized bindings: gpio, sqlite * lua(4): - removed floating-point and libc dependencies using '#ifndef _KERNEL' - fixed division by zero and exponentiation - libkern: added isalnum(), iscntrl(), isgraph(), isprint() and ispunct() - acpica: removed isprint() from acnetbsd.h - libc: moved strcspn.c, strpbrk.c and strspn.c to common - removed stub headers - compatibilized bindings: luapmf, luasystm * reorganized luaconf.h * updated doc/CHANGES and doc/RESPONSIBLE
Diffstat (limited to 'external/mit/lua/dist/src/lstring.c')
-rw-r--r--external/mit/lua/dist/src/lstring.c193
1 files changed, 132 insertions, 61 deletions
diff --git a/external/mit/lua/dist/src/lstring.c b/external/mit/lua/dist/src/lstring.c
index 07350b78f27..b5163ef7001 100644
--- a/external/mit/lua/dist/src/lstring.c
+++ b/external/mit/lua/dist/src/lstring.c
@@ -1,19 +1,23 @@
-/* $NetBSD: lstring.c,v 1.1.1.2 2012/03/15 00:08:08 alnsn Exp $ */
+/* $NetBSD: lstring.c,v 1.2 2014/07/19 18:38:34 lneto Exp $ */
/*
-** $Id: lstring.c,v 1.1.1.2 2012/03/15 00:08:08 alnsn Exp $
+** $Id: lstring.c,v 1.2 2014/07/19 18:38:34 lneto Exp $
** String table (keeps all strings handled by Lua)
** See Copyright Notice in lua.h
*/
+#ifndef _KERNEL
#include <string.h>
+#endif
#define lstring_c
#define LUA_CORE
#include "lua.h"
+#include "ldebug.h"
+#include "ldo.h"
#include "lmem.h"
#include "lobject.h"
#include "lstate.h"
@@ -21,93 +25,160 @@
+/*
+** Lua will use at most ~(2^LUAI_HASHLIMIT) bytes from a string to
+** compute its hash
+*/
+#if !defined(LUAI_HASHLIMIT)
+#define LUAI_HASHLIMIT 5
+#endif
+
+
+/*
+** equality for long strings
+*/
+int luaS_eqlngstr (TString *a, TString *b) {
+ size_t len = a->tsv.len;
+ lua_assert(a->tsv.tt == LUA_TLNGSTR && b->tsv.tt == LUA_TLNGSTR);
+ return (a == b) || /* same instance or... */
+ ((len == b->tsv.len) && /* 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) {
+ unsigned int h = seed ^ cast(unsigned int, l);
+ size_t l1;
+ size_t step = (l >> LUAI_HASHLIMIT) + 1;
+ for (l1 = l; l1 >= step; l1 -= step)
+ h = h ^ ((h<<5) + (h>>2) + cast_byte(str[l1 - 1]));
+ return h;
+}
+
+
+/*
+** resizes the string table
+*/
void luaS_resize (lua_State *L, int newsize) {
- GCObject **newhash;
- stringtable *tb;
int i;
- if (G(L)->gcstate == GCSsweepstring)
- return; /* cannot resize during GC traverse */
- newhash = luaM_newvector(L, newsize, GCObject *);
- tb = &G(L)->strt;
- for (i=0; i<newsize; i++) newhash[i] = NULL;
- /* rehash */
- for (i=0; i<tb->size; i++) {
- GCObject *p = tb->hash[i];
+ stringtable *tb = &G(L)->strt;
+ if (newsize > tb->size) { /* grow table if needed */
+ luaM_reallocvector(L, tb->hash, tb->size, newsize, TString *);
+ for (i = tb->size; i < newsize; i++)
+ tb->hash[i] = NULL;
+ }
+ for (i = 0; i < tb->size; i++) { /* rehash */
+ TString *p = tb->hash[i];
+ tb->hash[i] = NULL;
while (p) { /* for each node in the list */
- GCObject *next = p->gch.next; /* save next */
- unsigned int h = gco2ts(p)->hash;
- int h1 = lmod(h, newsize); /* new position */
- lua_assert(cast_int(h%newsize) == lmod(h, newsize));
- p->gch.next = newhash[h1]; /* chain it */
- newhash[h1] = p;
- p = next;
+ TString *hnext = p->tsv.hnext; /* save next */
+ unsigned int h = lmod(p->tsv.hash, newsize); /* new position */
+ p->tsv.hnext = tb->hash[h]; /* chain it */
+ tb->hash[h] = p;
+ p = hnext;
}
}
- luaM_freearray(L, tb->hash, tb->size, TString *);
+ if (newsize < tb->size) { /* shrink table if needed */
+ /* vanishing slice should be empty */
+ lua_assert(tb->hash[newsize] == NULL && tb->hash[tb->size - 1] == NULL);
+ luaM_reallocvector(L, tb->hash, tb->size, newsize, TString *);
+ }
tb->size = newsize;
- tb->hash = newhash;
}
-static TString *newlstr (lua_State *L, const char *str, size_t l,
- unsigned int h) {
+
+/*
+** creates a new string object
+*/
+static TString *createstrobj (lua_State *L, const char *str, size_t l,
+ int tag, unsigned int h) {
TString *ts;
- stringtable *tb;
- if (l+1 > (MAX_SIZET - sizeof(TString))/sizeof(char))
- luaM_toobig(L);
- ts = cast(TString *, luaM_malloc(L, (l+1)*sizeof(char)+sizeof(TString)));
+ GCObject *o;
+ size_t totalsize; /* total size of TString object */
+ totalsize = sizeof(TString) + ((l + 1) * sizeof(char));
+ o = luaC_newobj(L, tag, totalsize);
+ ts = rawgco2ts(o);
ts->tsv.len = l;
ts->tsv.hash = h;
- ts->tsv.marked = luaC_white(G(L));
- ts->tsv.tt = LUA_TSTRING;
- ts->tsv.reserved = 0;
+ ts->tsv.extra = 0;
memcpy(ts+1, str, l*sizeof(char));
((char *)(ts+1))[l] = '\0'; /* ending 0 */
- tb = &G(L)->strt;
- h = lmod(h, tb->size);
- ts->tsv.next = tb->hash[h]; /* chain new entry */
- tb->hash[h] = obj2gco(ts);
- tb->nuse++;
- if (tb->nuse > cast(lu_int32, tb->size) && tb->size <= MAX_INT/2)
- luaS_resize(L, tb->size*2); /* too crowded */
return ts;
}
-TString *luaS_newlstr (lua_State *L, const char *str, size_t l) {
- GCObject *o;
- unsigned int h = cast(unsigned int, l); /* seed */
- size_t step = (l>>5)+1; /* if string is too long, don't hash all its chars */
- size_t l1;
- for (l1=l; l1>=step; l1-=step) /* compute hash */
- h = h ^ ((h<<5)+(h>>2)+cast(unsigned char, str[l1-1]));
- for (o = G(L)->strt.hash[lmod(h, G(L)->strt.size)];
- o != NULL;
- o = o->gch.next) {
- TString *ts = rawgco2ts(o);
- if (ts->tsv.len == l && (memcmp(str, getstr(ts), l) == 0)) {
- /* string may be dead */
- if (isdead(G(L), o)) changewhite(o);
+void luaS_remove (lua_State *L, TString *ts) {
+ stringtable *tb = &G(L)->strt;
+ TString **p = &tb->hash[lmod(ts->tsv.hash, tb->size)];
+ while (*p != ts) /* find previous element */
+ p = &(*p)->tsv.hnext;
+ *p = (*p)->tsv.hnext; /* remove element from its list */
+ tb->nuse--;
+}
+
+
+/*
+** 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);
+ unsigned int h = luaS_hash(str, l, g->seed);
+ TString **list = &g->strt.hash[lmod(h, g->strt.size)];
+ for (ts = *list; ts != NULL; ts = ts->tsv.hnext) {
+ if (l == ts->tsv.len &&
+ (memcmp(str, getstr(ts), l * sizeof(char)) == 0)) {
+ /* found! */
+ if (isdead(g, obj2gco(ts))) /* dead (but not collected yet)? */
+ changewhite(obj2gco(ts)); /* resurrect it */
return ts;
}
}
- return newlstr(L, str, l, h); /* not found */
+ if (g->strt.nuse >= g->strt.size && g->strt.size <= MAX_INT/2) {
+ luaS_resize(L, g->strt.size * 2);
+ list = &g->strt.hash[lmod(h, g->strt.size)]; /* recompute with new size */
+ }
+ ts = createstrobj(L, str, l, LUA_TSHRSTR, h);
+ ts->tsv.hnext = *list;
+ *list = ts;
+ g->strt.nuse++;
+ return ts;
}
-Udata *luaS_newudata (lua_State *L, size_t s, Table *e) {
+/*
+** 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 {
+ if (l + 1 > (MAX_SIZE - sizeof(TString))/sizeof(char))
+ luaM_toobig(L);
+ return createstrobj(L, str, l, LUA_TLNGSTR, G(L)->seed);
+ }
+}
+
+
+/*
+** new zero-terminated string
+*/
+TString *luaS_new (lua_State *L, const char *str) {
+ return luaS_newlstr(L, str, strlen(str));
+}
+
+
+Udata *luaS_newudata (lua_State *L, size_t s) {
Udata *u;
- if (s > MAX_SIZET - sizeof(Udata))
+ GCObject *o;
+ if (s > MAX_SIZE - sizeof(Udata))
luaM_toobig(L);
- u = cast(Udata *, luaM_malloc(L, s + sizeof(Udata)));
- u->uv.marked = luaC_white(G(L)); /* is not finalized */
- u->uv.tt = LUA_TUSERDATA;
+ o = luaC_newobj(L, LUA_TUSERDATA, sizeof(Udata) + s);
+ u = rawgco2u(o);
u->uv.len = s;
u->uv.metatable = NULL;
- u->uv.env = e;
- /* chain it on udata list (after main thread) */
- u->uv.next = G(L)->mainthread->next;
- G(L)->mainthread->next = obj2gco(u);
+ setuservalue(L, u, luaO_nilobject);
return u;
}