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package bolt
const (
bigNode = 0x01
subNode = 0x02
dupNode = 0x04
)
type node struct {
lo int
hi int
flags int
keySize int
data []byte
}
func (n *node) setFlags(f int) {
// Valid flags: (F_DUPDATA|F_SUBDATA|MDB_RESERVE|MDB_APPEND)
// TODO
}
func (n *node) size() int {
return 0 // TODO: offsetof(MDB_node, mn_data)
}
// TODO: #define INDXSIZE(k) (NODESIZE + ((k) == NULL ? 0 : (k)->mv_size))
// TODO: #define LEAFSIZE(k, d) (NODESIZE + (k)->mv_size + (d)->mv_size)
// TODO: #define NODEPTR(p, i) ((MDB_node *)((char *)(p) + (p)->mp_ptrs[i]))
// TODO: #define NODEKEY(node) (void *)((node)->mn_data)
// TODO: #define NODEDATA(node) (void *)((char *)(node)->mn_data + (node)->mn_ksize)
// TODO: #define NODEPGNO(node) ((node)->mn_lo | ((pgno_t) (node)->mn_hi << 16) | (PGNO_TOPWORD ? ((pgno_t) (node)->mn_flags << PGNO_TOPWORD) : 0))
// TODO: #define SETPGNO(node,pgno) do { (node)->mn_lo = (pgno) & 0xffff; (node)->mn_hi = (pgno) >> 16; if (PGNO_TOPWORD) (node)->mn_flags = (pgno) >> PGNO_TOPWORD; } while(0)
// TODO: #define NODEDSZ(node) ((node)->mn_lo | ((unsigned)(node)->mn_hi << 16))
// TODO: #define SETDSZ(node,size) do { (node)->mn_lo = (size) & 0xffff; (node)->mn_hi = (size) >> 16;} while(0)
// TODO: #define NODEKSZ(node) ((node)->mn_ksize)
// TODO: #define LEAF2KEY(p, i, ks) ((char *)(p) + PAGEHDRSZ + ((i)*(ks)))
// TODO: #define MDB_GET_KEY(node, keyptr) { if ((keyptr) != NULL) { (keyptr)->mv_size = NODEKSZ(node); (keyptr)->mv_data = NODEKEY(node); } }
// TODO: #define MDB_GET_KEY2(node, key) { key.mv_size = NODEKSZ(node); key.mv_data = NODEKEY(node); }
// Compact the main page after deleting a node on a subpage.
// @param[in] mp The main page to operate on.
// @param[in] indx The index of the subpage on the main page.
func (n *node) shrink(index int) {
/*
MDB_node *node;
MDB_page *sp, *xp;
char *base;
int nsize, delta;
indx_t i, numkeys, ptr;
node = NODEPTR(mp, indx);
sp = (MDB_page *)NODEDATA(node);
delta = SIZELEFT(sp);
xp = (MDB_page *)((char *)sp + delta);
// shift subpage upward
if (IS_LEAF2(sp)) {
nsize = NUMKEYS(sp) * sp->mp_pad;
if (nsize & 1)
return; // do not make the node uneven-sized
memmove(METADATA(xp), METADATA(sp), nsize);
} else {
int i;
numkeys = NUMKEYS(sp);
for (i=numkeys-1; i>=0; i--)
xp->mp_ptrs[i] = sp->mp_ptrs[i] - delta;
}
xp->mp_upper = sp->mp_lower;
xp->mp_lower = sp->mp_lower;
xp->mp_flags = sp->mp_flags;
xp->mp_pad = sp->mp_pad;
COPY_PGNO(xp->mp_pgno, mp->mp_pgno);
nsize = NODEDSZ(node) - delta;
SETDSZ(node, nsize);
// shift lower nodes upward
ptr = mp->mp_ptrs[indx];
numkeys = NUMKEYS(mp);
for (i = 0; i < numkeys; i++) {
if (mp->mp_ptrs[i] <= ptr)
mp->mp_ptrs[i] += delta;
}
base = (char *)mp + mp->mp_upper;
memmove(base + delta, base, ptr - mp->mp_upper + NODESIZE + NODEKSZ(node));
mp->mp_upper += delta;
*/
}
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