136 lines
4.0 KiB
C
136 lines
4.0 KiB
C
/* Read-only tables for Lua */
|
|
|
|
#include <string.h>
|
|
#include "lrotable.h"
|
|
#include "lua.h"
|
|
#include "lauxlib.h"
|
|
#include "lstring.h"
|
|
#include "lobject.h"
|
|
#include "lapi.h"
|
|
|
|
/* Local defines */
|
|
#define LUAR_FINDFUNCTION 0
|
|
#define LUAR_FINDVALUE 1
|
|
|
|
/* Externally defined read-only table array */
|
|
extern const luaR_table lua_rotable[];
|
|
|
|
/* Find a global "read only table" in the constant lua_rotable array */
|
|
void* luaR_findglobal(const char *name, unsigned len) {
|
|
unsigned i;
|
|
|
|
if (strlen(name) > LUA_MAX_ROTABLE_NAME)
|
|
return NULL;
|
|
for (i=0; lua_rotable[i].name; i ++)
|
|
if (*lua_rotable[i].name != '\0' && strlen(lua_rotable[i].name) == len && !strncmp(lua_rotable[i].name, name, len)) {
|
|
return (void*)(lua_rotable[i].pentries);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/* Find an entry in a rotable and return it */
|
|
static const TValue* luaR_auxfind(const luaR_entry *pentry, const char *strkey, luaR_numkey numkey, unsigned *ppos) {
|
|
const TValue *res = NULL;
|
|
unsigned i = 0;
|
|
|
|
if (pentry == NULL)
|
|
return NULL;
|
|
while(pentry->key.type != LUA_TNIL) {
|
|
if ((strkey && (pentry->key.type == LUA_TSTRING) && (!strcmp(pentry->key.id.strkey, strkey))) ||
|
|
(!strkey && (pentry->key.type == LUA_TNUMBER) && ((luaR_numkey)pentry->key.id.numkey == numkey))) {
|
|
res = &pentry->value;
|
|
break;
|
|
}
|
|
i ++; pentry ++;
|
|
}
|
|
if (res && ppos)
|
|
*ppos = i;
|
|
return res;
|
|
}
|
|
|
|
int luaR_findfunction(lua_State *L, const luaR_entry *ptable) {
|
|
const TValue *res = NULL;
|
|
const char *key = luaL_checkstring(L, 2);
|
|
|
|
res = luaR_auxfind(ptable, key, 0, NULL);
|
|
if (res && ttislightfunction(res)) {
|
|
luaA_pushobject(L, res);
|
|
return 1;
|
|
}
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
/* Find an entry in a rotable and return its type
|
|
If "strkey" is not NULL, the function will look for a string key,
|
|
otherwise it will look for a number key */
|
|
const TValue* luaR_findentry(void *data, const char *strkey, luaR_numkey numkey, unsigned *ppos) {
|
|
return luaR_auxfind((const luaR_entry*)data, strkey, numkey, ppos);
|
|
}
|
|
|
|
/* Find the metatable of a given table */
|
|
void* luaR_getmeta(void *data) {
|
|
#ifdef LUA_META_ROTABLES
|
|
const TValue *res = luaR_auxfind((const luaR_entry*)data, "__metatable", 0, NULL);
|
|
return res && ttisrotable(res) ? rvalue(res) : NULL;
|
|
#else
|
|
return NULL;
|
|
#endif
|
|
}
|
|
|
|
static void luaR_next_helper(lua_State *L, const luaR_entry *pentries, int pos, TValue *key, TValue *val) {
|
|
setnilvalue(key);
|
|
setnilvalue(val);
|
|
if (pentries[pos].key.type != LUA_TNIL) {
|
|
/* Found an entry */
|
|
if (pentries[pos].key.type == LUA_TSTRING)
|
|
setsvalue(L, key, luaS_newro(L, pentries[pos].key.id.strkey))
|
|
else
|
|
setnvalue(key, (lua_Number)pentries[pos].key.id.numkey)
|
|
setobj2s(L, val, &pentries[pos].value);
|
|
}
|
|
}
|
|
/* next (used for iteration) */
|
|
void luaR_next(lua_State *L, void *data, TValue *key, TValue *val) {
|
|
const luaR_entry* pentries = (const luaR_entry*)data;
|
|
char strkey[LUA_MAX_ROTABLE_NAME + 1], *pstrkey = NULL;
|
|
luaR_numkey numkey = 0;
|
|
unsigned keypos;
|
|
|
|
/* Special case: if key is nil, return the first element of the rotable */
|
|
if (ttisnil(key))
|
|
luaR_next_helper(L, pentries, 0, key, val);
|
|
else if (ttisstring(key) || ttisnumber(key)) {
|
|
/* Find the previoud key again */
|
|
if (ttisstring(key)) {
|
|
luaR_getcstr(strkey, rawtsvalue(key), LUA_MAX_ROTABLE_NAME);
|
|
pstrkey = strkey;
|
|
} else
|
|
numkey = (luaR_numkey)nvalue(key);
|
|
luaR_findentry(data, pstrkey, numkey, &keypos);
|
|
/* Advance to next key */
|
|
keypos ++;
|
|
luaR_next_helper(L, pentries, keypos, key, val);
|
|
}
|
|
}
|
|
|
|
/* Convert a Lua string to a C string */
|
|
void luaR_getcstr(char *dest, const TString *src, size_t maxsize) {
|
|
if (src->tsv.len+1 > maxsize)
|
|
dest[0] = '\0';
|
|
else {
|
|
memcpy(dest, getstr(src), src->tsv.len);
|
|
dest[src->tsv.len] = '\0';
|
|
}
|
|
}
|
|
|
|
/* Return 1 if the given pointer is a rotable */
|
|
#ifdef LUA_META_ROTABLES
|
|
|
|
#include "compiler.h"
|
|
|
|
int luaR_isrotable(void *p) {
|
|
return RODATA_START_ADDRESS <= (char*)p && (char*)p <= RODATA_END_ADDRESS;
|
|
}
|
|
#endif
|