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author | Kartik K. Agaram <vc@akkartik.com> | 2021-10-19 21:38:48 -0700 |
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committer | Kartik K. Agaram <vc@akkartik.com> | 2021-10-22 19:24:44 -0700 |
commit | 74f8cd15bb43110973deffdeb9dd229797e5b328 (patch) | |
tree | 12d6b5475a786eacf7a5a79b03b2b85621578ec6 /src/lstring.c | |
download | teliva-74f8cd15bb43110973deffdeb9dd229797e5b328.tar.gz |
new fork of Lua 5.1
https://www.lua.org
Diffstat (limited to 'src/lstring.c')
-rw-r--r-- | src/lstring.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/src/lstring.c b/src/lstring.c new file mode 100644 index 0000000..4911315 --- /dev/null +++ b/src/lstring.c @@ -0,0 +1,111 @@ +/* +** $Id: lstring.c,v 2.8.1.1 2007/12/27 13:02:25 roberto Exp $ +** String table (keeps all strings handled by Lua) +** See Copyright Notice in lua.h +*/ + + +#include <string.h> + +#define lstring_c +#define LUA_CORE + +#include "lua.h" + +#include "lmem.h" +#include "lobject.h" +#include "lstate.h" +#include "lstring.h" + + + +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]; + 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; + } + } + luaM_freearray(L, tb->hash, tb->size, TString *); + tb->size = newsize; + tb->hash = newhash; +} + + +static TString *newlstr (lua_State *L, const char *str, size_t l, + 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))); + ts->tsv.len = l; + ts->tsv.hash = h; + ts->tsv.marked = luaC_white(G(L)); + ts->tsv.tt = LUA_TSTRING; + ts->tsv.reserved = 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); + return ts; + } + } + return newlstr(L, str, l, h); /* not found */ +} + + +Udata *luaS_newudata (lua_State *L, size_t s, Table *e) { + Udata *u; + if (s > MAX_SIZET - 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; + 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); + return u; +} + |