0
0
mirror of https://gitlab.nic.cz/labs/bird.git synced 2024-12-23 10:11:53 +00:00
bird/lua/filter.c

136 lines
3.3 KiB
C
Raw Normal View History

#include "nest/bird.h"
2018-01-23 14:11:08 +00:00
#include "conf/conf.h"
#include "filter/filter.h"
2017-02-06 14:25:48 +00:00
#include "lua.h"
#include <lua.h>
#include <lualib.h>
#include <lauxlib.h>
/* Docs: http://pgl.yoyo.org/luai/i/luaL_dostring */
2018-01-23 14:11:08 +00:00
struct lua_new_filter_writer_data {
struct lua_filter_chunk *first, *last;
};
static int lua_new_filter_writer(lua_State *L UNUSED, const void *p, size_t sz, void *ud) {
struct lua_new_filter_writer_data *d = ud;
struct lua_filter_chunk *cur = cfg_allocz(sizeof(struct lua_filter_chunk));
cur->size = sz;
cur->chunk = cfg_alloc(sz);
memcpy(cur->chunk, p, sz);
if (d->last)
d->last = d->last->next = cur;
else
d->last = d->first = cur;
return 0;
}
struct filter * lua_new_filter(struct f_inst *inst) {
struct filter *f = cfg_alloc(sizeof(struct filter));
f->name = NULL;
f->type = FILTER_LUA;
struct f_val string = f_eval(inst, cfg_mem);
if (string.type != T_STRING) {
cf_error("Lua filter must be a string");
return NULL;
}
lua_State *L = luaL_newstate();
luaL_openlibs(L);
int loadres = luaL_loadstring(L, string.val.s);
switch (loadres) {
case LUA_ERRMEM:
lua_close(L);
cf_error("Memory allocation error occured when loading lua chunk");
return NULL;
case LUA_ERRSYNTAX:
{
const char *e = lua_tostring(L, -1);
char *ec = cfg_alloc(strlen(e) + 1);
strcpy(ec, e);
lua_close(L);
cf_error("Lua syntax error: %s", ec);
return NULL;
}
case 0: /* Everything OK */
break;
}
struct lua_new_filter_writer_data lnfwd = {};
lua_dump(L, lua_new_filter_writer, &lnfwd, 0); /* No error to handle */
lua_close(L);
f->lua_chunk = lnfwd.first;
return f;
}
static const char *lua_interpret_reader(lua_State *L UNUSED, void *ud, size_t *sz) {
struct lua_filter_chunk **cptr = ud;
if ((*cptr) == NULL)
return NULL;
*sz = (*cptr)->size;
void *out = (*cptr)->chunk;
*cptr = (*cptr)->next;
return out;
}
struct f_val lua_interpret(struct lua_filter_chunk *chunk, struct rte **e, struct rta **a, struct ea_list **ea, struct linpool *lp, int flags) {
lua_State *L = luaL_newstate();
luaL_openlibs(L);
lua_bird_state *lbs = luaB_init(L, lp);
2017-02-08 11:36:32 +00:00
luaB_push_route(L, *e);
2018-01-23 14:11:08 +00:00
struct lua_filter_chunk **rptr = &chunk;
lua_load(L, lua_interpret_reader, rptr, "", "b");
int le = lua_pcall(L, 0, LUA_MULTRET, 0);
struct f_val out = F_VAL_VOID;
if (le && lbs->exception) {
out = F_VAL(T_RETURN, i, lbs->exception);
} else if (le) {
log(L_ERR "bad lua: %s", lua_tostring(L, -1));
out = F_VAL(T_RETURN, i, F_ERROR);
} else if (lua_isnumber(L, -1)) {
out = F_VAL(T_INT, i, lua_tonumber(L, -1));
} else {
log(L_WARN "lua return value is not a number (unimplemented): %s", lua_tostring(L, -1));
out = F_VAL(T_RETURN, i, F_ERROR);
}
lua_close(L);
return out;
}
2018-01-23 14:11:08 +00:00
int lua_filter_same(struct lua_filter_chunk *new, struct lua_filter_chunk *old) {
size_t npos = 0, opos = 0;
while (new && old) {
size_t nrem = new->size - npos;
size_t orem = old->size - opos;
size_t rem = MIN(nrem, orem);
if (memcmp(new->chunk + npos, old->chunk + opos, rem))
return 0;
npos += rem;
opos += rem;
if (npos == new->size) {
new = new->next;
npos = 0;
}
if (opos == old->size) {
old = old->next;
opos = 0;
}
}
if (!new && !old)
return 1;
else
return 0;
}