static struct item* _item_alloc(uint8_t id, char *key, uint16_t nkey, int exptime, char *value, uint32_t nbyte) {
struct item *it;
struct item *uit;
assert(id >= SLABCLASS_MIN_ID && id <= SLABCLASS_MAX_ID);
it = item_get_from_lruq(id);
if (it != NULL && item_expired(it)) {
item_reuse(it);
goto done;
}
uit = (settings.evict_opt & EVICT_LRU)? it : NULL;
it = slab_get_item(id);
if (it != NULL) {
goto done;
}
if (uit != NULL) {
it = uit;
item_reuse(it);
goto done;
}
return NULL;
done:
assert(it->id == id);
assert(!item_is_linked(it));
assert(!item_is_slabbed(it));
assert(it->offset != 0);
assert(it->refcount == 0);
it->flags = 0;
it->nbyte = nbyte;
it->exptime = exptime + time_now();
it->nkey = nkey;
memcpy(item_key(it), key, nkey);
memcpy(item_key(it) + nkey, value, nbyte);
return it;
}
static void
req_process_add(struct context *ctx, struct conn *conn, struct msg *msg)
{
struct itemx *itx;
struct item *it;
/* add, adds only if the mapping is not present */
itx = itemx_getx(msg->hash, msg->md);
if (itx != NULL) {
it = slab_read_item(itx->sid, itx->offset);
/* if the item hasn't expired yet */
if(!item_expired(it)) {
rsp_send_status(ctx, conn, msg, MSG_RSP_NOT_STORED);
return;
}
}
req_process_set(ctx, conn, msg);
}
static struct item* item_get_from_lruq(uint8_t id) {
struct item *it;
struct item *uit;
uint32_t tries;
if (!settings.use_lruq) {
return NULL;
}
for (tries = ITEM_LRUQ_MAX_TRIES, it = TAILQ_FIRST(&item_lruq[id]), uit = NULL;
it != NULL && tries > 0; tries--, it = TAILQ_NEXT(it, i_tqe)) {
if (it->refcount != 0) {
continue;
}
if (item_expired(it)) {
return it;
} else if (uit == NULL) {
uit = it;
}
}
return uit;
}
static void
req_process_get(struct context *ctx, struct conn *conn, struct msg *msg)
{
struct itemx *itx;
struct item *it;
itx = itemx_getx(msg->hash, msg->md);
if (itx == NULL) {
msg_type_t type;
/*
* On a miss, we send a "END\r\n" response, unless the request
* is an intermediate fragment in a fragmented request.
*/
if (msg->frag_id == 0 || msg->last_fragment) {
type = MSG_RSP_END;
} else {
type = MSG_EMPTY;
}
rsp_send_status(ctx, conn, msg, type);
return;
}
/*
* On a hit, we read the item with address [sid, offset] and respond
* with item value if the item hasn't expired yet.
*/
it = slab_read_item(itx->sid, itx->offset);
if (it == NULL) {
rsp_send_error(ctx, conn, msg, MSG_RSP_SERVER_ERROR, errno);
return;
}
if (item_expired(it)) {
rsp_send_status(ctx, conn, msg, MSG_RSP_NOT_FOUND);
return;
}
rsp_send_value(ctx, conn, msg, it, itx->cas);
}
static void
req_process_replace(struct context *ctx, struct conn *conn, struct msg *msg)
{
struct itemx *itx;
struct item *it;
/* replace, only replaces if the mapping is present */
itx = itemx_getx(msg->hash, msg->md);
if (itx == NULL) {
rsp_send_status(ctx, conn, msg, MSG_RSP_NOT_STORED);
return;
}
/* if the item has expired */
it = slab_read_item(itx->sid, itx->offset);
if(item_expired(it)) {
rsp_send_status(ctx, conn, msg, MSG_RSP_NOT_STORED);
return;
}
req_process_set(ctx, conn, msg);
}
static void
req_process_num(struct context *ctx, struct conn *conn, struct msg *msg)
{
rstatus_t status;
uint8_t *key, nkey, cid;
struct item *it;
struct itemx *itx;
uint64_t cnum, nnum;
char numstr[FC_UINT64_MAXLEN];
int n;
key = msg->key_start;
nkey = (uint8_t)(msg->key_end - msg->key_start);
/* 1). look up existing itemx */
itx = itemx_getx(msg->hash, msg->md);
if (itx == NULL) {
/* 2a). miss -> return NOT_FOUND */
rsp_send_status(ctx, conn, msg, MSG_RSP_NOT_FOUND);
return;
}
/* 2b). hit -> read existing item into it */
it = slab_read_item(itx->sid, itx->offset);
if (it == NULL) {
rsp_send_error(ctx, conn, msg, MSG_RSP_SERVER_ERROR, errno);
return;
}
if (item_expired(it)) {
rsp_send_status(ctx, conn, msg, MSG_RSP_NOT_FOUND);
return;
}
/* 3). sanity check item data to be a number */
status = fc_atou64(item_data(it), it->ndata, &cnum);
if (status != FC_OK) {
rsp_send_error(ctx, conn, msg, MSG_RSP_CLIENT_ERROR, EINVAL);
return;
}
/* 4). remove existing itemx of it */
itemx_removex(msg->hash, msg->md);
/* 5). compute the new incr/decr number nnum and numstr */
if (msg->type == MSG_REQ_INCR) {
nnum = cnum + msg->num;
} else {
if (cnum < msg->num) {
nnum = 0;
} else {
nnum = cnum - msg->num;
}
}
n = fc_scnprintf(numstr, sizeof(numstr), "%"PRIu64"", nnum);
/* 6). alloc new item that can hold n worth of bytes */
cid = item_slabcid(nkey, n);
ASSERT(cid != SLABCLASS_INVALID_ID);
it = item_get(key, nkey, cid, n, time_reltime(msg->expiry), msg->flags,
msg->md, msg->hash);
if (it == NULL) {
rsp_send_error(ctx, conn, msg, MSG_RSP_SERVER_ERROR, ENOMEM);
return;
}
/* 7). copy numstr to it */
fc_memcpy(item_data(it), numstr, n);
rsp_send_num(ctx, conn, msg, it);
}
static void
req_process_concat(struct context *ctx, struct conn *conn, struct msg *msg)
{
uint8_t *key, nkey, cid;
struct item *oit, *it;
uint32_t ndata;
struct itemx *itx;
key = msg->key_start;
nkey = (uint8_t)(msg->key_end - msg->key_start);
/* 1). look up existing itemx */
itx = itemx_getx(msg->hash, msg->md);
if (itx == NULL) {
/* 2a). miss -> return NOT_STORED */
rsp_send_status(ctx, conn, msg, MSG_RSP_NOT_STORED);
return;
}
/* 2b). hit -> read existing item into oit */
oit = slab_read_item(itx->sid, itx->offset);
if (oit == NULL) {
rsp_send_error(ctx, conn, msg, MSG_RSP_SERVER_ERROR, errno);
return;
}
if (item_expired(oit)) {
rsp_send_status(ctx, conn, msg, MSG_RSP_NOT_STORED);
return;
}
ndata = msg->vlen + oit->ndata;
cid = item_slabcid(nkey, ndata);
if (cid == SLABCLASS_INVALID_ID) {
rsp_send_error(ctx, conn, msg, MSG_RSP_CLIENT_ERROR, EINVAL);
return;
}
/* 3). remove existing itemx of oit */
itemx_removex(msg->hash, msg->md);
/* 4). alloc new item that can hold ndata worth of bytes */
it = item_get(key, nkey, cid, ndata, time_reltime(msg->expiry),
msg->flags, msg->md, msg->hash);
if (it == NULL) {
rsp_send_error(ctx, conn, msg, MSG_RSP_SERVER_ERROR, ENOMEM);
return;
}
/* 5). copy data from msg to head or tail of new item it */
switch (msg->type) {
case MSG_REQ_PREPEND:
mbuf_copy_to(&msg->mhdr, msg->value, item_data(it), msg->vlen);
fc_memcpy(item_data(it) + msg->vlen, item_data(oit), oit->ndata);
break;
case MSG_REQ_APPEND:
fc_memcpy(item_data(it), item_data(oit), oit->ndata);
mbuf_copy_to(&msg->mhdr, msg->value, item_data(it) + oit->ndata, msg->vlen);
break;
default:
NOT_REACHED();
}
rsp_send_status(ctx, conn, msg, MSG_RSP_STORED);
}
