Index: third_party/lua/src/lstring.c |
diff --git a/third_party/lua/src/lstring.c b/third_party/lua/src/lstring.c |
new file mode 100644 |
index 0000000000000000000000000000000000000000..8b5af0b2e77cc23757d2187a76e8c01dcda0e7a9 |
--- /dev/null |
+++ b/third_party/lua/src/lstring.c |
@@ -0,0 +1,185 @@ |
+/* |
+** $Id: lstring.c,v 2.26 2013/01/08 13:50:10 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" |
+ |
+ |
+/* |
+** 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 */ |
+} |
+ |
+ |
+/* |
+** equality for strings |
+*/ |
+int luaS_eqstr (TString *a, TString *b) { |
+ return (a->tsv.tt == b->tsv.tt) && |
+ (a->tsv.tt == LUA_TSHRSTR ? eqshrstr(a, b) : luaS_eqlngstr(a, b)); |
+} |
+ |
+ |
+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) { |
+ int i; |
+ stringtable *tb = &G(L)->strt; |
+ /* cannot resize while GC is traversing strings */ |
+ luaC_runtilstate(L, ~bitmask(GCSsweepstring)); |
+ if (newsize > tb->size) { |
+ luaM_reallocvector(L, tb->hash, tb->size, newsize, GCObject *); |
+ for (i = tb->size; i < newsize; i++) tb->hash[i] = NULL; |
+ } |
+ /* rehash */ |
+ for (i=0; i<tb->size; i++) { |
+ GCObject *p = tb->hash[i]; |
+ tb->hash[i] = NULL; |
+ while (p) { /* for each node in the list */ |
+ GCObject *next = gch(p)->next; /* save next */ |
+ unsigned int h = lmod(gco2ts(p)->hash, newsize); /* new position */ |
+ gch(p)->next = tb->hash[h]; /* chain it */ |
+ tb->hash[h] = p; |
+ resetoldbit(p); /* see MOVE OLD rule */ |
+ p = next; |
+ } |
+ } |
+ if (newsize < tb->size) { |
+ /* shrinking slice must be empty */ |
+ lua_assert(tb->hash[newsize] == NULL && tb->hash[tb->size - 1] == NULL); |
+ luaM_reallocvector(L, tb->hash, tb->size, newsize, GCObject *); |
+ } |
+ tb->size = newsize; |
+} |
+ |
+ |
+/* |
+** creates a new string object |
+*/ |
+static TString *createstrobj (lua_State *L, const char *str, size_t l, |
+ int tag, unsigned int h, GCObject **list) { |
+ TString *ts; |
+ size_t totalsize; /* total size of TString object */ |
+ totalsize = sizeof(TString) + ((l + 1) * sizeof(char)); |
+ ts = &luaC_newobj(L, tag, totalsize, list, 0)->ts; |
+ ts->tsv.len = l; |
+ ts->tsv.hash = h; |
+ ts->tsv.extra = 0; |
+ memcpy(ts+1, str, l*sizeof(char)); |
+ ((char *)(ts+1))[l] = '\0'; /* ending 0 */ |
+ return ts; |
+} |
+ |
+ |
+/* |
+** creates a new short string, inserting it into string table |
+*/ |
+static TString *newshrstr (lua_State *L, const char *str, size_t l, |
+ unsigned int h) { |
+ GCObject **list; /* (pointer to) list where it will be inserted */ |
+ stringtable *tb = &G(L)->strt; |
+ TString *s; |
+ if (tb->nuse >= cast(lu_int32, tb->size) && tb->size <= MAX_INT/2) |
+ luaS_resize(L, tb->size*2); /* too crowded */ |
+ list = &tb->hash[lmod(h, tb->size)]; |
+ s = createstrobj(L, str, l, LUA_TSHRSTR, h, list); |
+ tb->nuse++; |
+ return s; |
+} |
+ |
+ |
+/* |
+** 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) { |
+ GCObject *o; |
+ global_State *g = G(L); |
+ unsigned int h = luaS_hash(str, l, g->seed); |
+ for (o = g->strt.hash[lmod(h, g->strt.size)]; |
+ o != NULL; |
+ o = gch(o)->next) { |
+ TString *ts = rawgco2ts(o); |
+ if (h == ts->tsv.hash && |
+ l == ts->tsv.len && |
+ (memcmp(str, getstr(ts), l * sizeof(char)) == 0)) { |
+ if (isdead(G(L), o)) /* string is dead (but was not collected yet)? */ |
+ changewhite(o); /* resurrect it */ |
+ return ts; |
+ } |
+ } |
+ return newshrstr(L, str, l, h); /* not found; create a new string */ |
+} |
+ |
+ |
+/* |
+** 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_SIZET - sizeof(TString))/sizeof(char)) |
+ luaM_toobig(L); |
+ return createstrobj(L, str, l, LUA_TLNGSTR, G(L)->seed, NULL); |
+ } |
+} |
+ |
+ |
+/* |
+** 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, Table *e) { |
+ Udata *u; |
+ if (s > MAX_SIZET - sizeof(Udata)) |
+ luaM_toobig(L); |
+ u = &luaC_newobj(L, LUA_TUSERDATA, sizeof(Udata) + s, NULL, 0)->u; |
+ u->uv.len = s; |
+ u->uv.metatable = NULL; |
+ u->uv.env = e; |
+ return u; |
+} |
+ |