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tokerstokers
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feature: implemented the lindex method for list type share dict value
The `lindex` method returns the element at index `index` in the shared dict list. Just like the `LINDEX` of Redis.
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Diff for: ‎README.markdown

+19
Original file line numberDiff line numberDiff line change
@@ -3185,6 +3185,7 @@ Nginx API for Lua
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* [ngx.shared.DICT.lpop](#ngxshareddictlpop)
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* [ngx.shared.DICT.rpop](#ngxshareddictrpop)
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* [ngx.shared.DICT.llen](#ngxshareddictllen)
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* [ngx.shared.DICT.lindex](#ngxshareddictlindex)
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* [ngx.shared.DICT.ttl](#ngxshareddictttl)
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* [ngx.shared.DICT.expire](#ngxshareddictexpire)
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* [ngx.shared.DICT.flush_all](#ngxshareddictflush_all)
@@ -6235,6 +6236,7 @@ The resulting object `dict` has the following methods:
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* [lpop](#ngxshareddictlpop)
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* [rpop](#ngxshareddictrpop)
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* [llen](#ngxshareddictllen)
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* [lindex](#ngxshareddictlindex)
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* [ttl](#ngxshareddictttl)
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* [expire](#ngxshareddictexpire)
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* [flush_all](#ngxshareddictflush_all)
@@ -6607,6 +6609,23 @@ See also [ngx.shared.DICT](#ngxshareddict).
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[Back to TOC](#nginx-api-for-lua)
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ngx.shared.DICT.lindex
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----------------------
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**syntax:** *val, err = ngx.shared.DICT:lindex(key, index)*
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**context:** *init_by_lua*, set_by_lua*, rewrite_by_lua*, access_by_lua*, content_by_lua*, header_filter_by_lua*, body_filter_by_lua*, log_by_lua*, ngx.timer.*, balancer_by_lua*, ssl_certificate_by_lua*, ssl_session_fetch_by_lua*, ssl_session_store_by_lua**
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Returns the element which at the index `index` of the list named `key` in the shm-base dictionary [ngx.shared.DICT](#ngxshareddict).
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The index is zero-based, so `0` means the first element, `1` for the second element and so forth. Also, negative index can be used to designate elements starting at the tail of the list, here `-1` means the last element and `-2` means the penultimate and so on.
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If `key` does not exist, it will return `nil`. When the `key` already takes a value that is not a list, it will return `nil` and `"value not a list"`. When `index` is out of the list length bound, the method will return `nil`.
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See also [ngx.shared.DICT](#ngxshareddict).
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[Back to TOC](#nginx-api-for-lua)
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ngx.shared.DICT.ttl
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-------------------
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**syntax:** *ttl, err = ngx.shared.DICT:ttl(key)*

Diff for: ‎doc/HttpLuaModule.wiki

+15
Original file line numberDiff line numberDiff line change
@@ -5232,6 +5232,7 @@ The resulting object <code>dict</code> has the following methods:
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* [[#ngx.shared.DICT.lpop|lpop]]
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* [[#ngx.shared.DICT.rpop|rpop]]
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* [[#ngx.shared.DICT.llen|llen]]
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* [[#ngx.shared.DICT.lindex|lindex]]
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* [[#ngx.shared.DICT.ttl|ttl]]
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* [[#ngx.shared.DICT.expire|expire]]
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* [[#ngx.shared.DICT.flush_all|flush_all]]
@@ -5553,6 +5554,20 @@ This feature was first introduced in the <code>v0.10.6</code> release.
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See also [[#ngx.shared.DICT|ngx.shared.DICT]].
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== ngx.shared.DICT.lindex ==
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'''syntax:''' ''val, err = ngx.shared.DICT:lindex(key, index)''
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'''context:''' ''init_by_lua*, set_by_lua*, rewrite_by_lua*, access_by_lua*, content_by_lua*, header_filter_by_lua*, body_filter_by_lua*, log_by_lua*, ngx.timer.*, balancer_by_lua*, ssl_certificate_by_lua*, ssl_session_fetch_by_lua*, ssl_session_store_by_lua*''
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Returns the element which at the index <code>index</code> of the list named <code>key</code> in the shm-base dictionary [[#ngx.shared.DICT|ngx.shared.DICT]].
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The index is zero-based, so <code>0</code> means the first element, <code>1</code> for the second element and so forth. Also, negative index can be used to designate elements starting at the tail of the list, here <code>-1</code> means the last element and <code>-2</code> means the penultimate and so on.
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If <code>key</code> does not exist, it will return <code>nil</code>. When the <code>key</code> already takes a value that is not a list, it will return <code>nil</code> and <code>"value not a list"</code>. When <code>index</code> is out of the list length bound, the method will return `nil`.
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See also [[#ngx.shared.DICT|ngx.shared.DICT]].
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== ngx.shared.DICT.ttl ==
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'''syntax:''' ''ttl, err = ngx.shared.DICT:ttl(key)''
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Diff for: ‎src/ngx_http_lua_shdict.c

+164-1
Original file line numberDiff line numberDiff line change
@@ -41,6 +41,7 @@ static int ngx_http_lua_shdict_lpop(lua_State *L);
4141
static int ngx_http_lua_shdict_rpop(lua_State *L);
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static int ngx_http_lua_shdict_pop_helper(lua_State *L, int flags);
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static int ngx_http_lua_shdict_llen(lua_State *L);
44+
static int ngx_http_lua_shdict_lindex(lua_State *L);
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4546

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static ngx_inline ngx_shm_zone_t *ngx_http_lua_shdict_get_zone(lua_State *L,
@@ -331,7 +332,7 @@ ngx_http_lua_inject_shdict_api(ngx_http_lua_main_conf_t *lmcf, lua_State *L)
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lua_createtable(L, 0, lmcf->shdict_zones->nelts /* nrec */);
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/* ngx.shared */
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lua_createtable(L, 0 /* narr */, 18 /* nrec */); /* shared mt */
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lua_createtable(L, 0 /* narr */, 19 /* nrec */); /* shared mt */
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lua_pushcfunction(L, ngx_http_lua_shdict_get);
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lua_setfield(L, -2, "get");
@@ -375,6 +376,9 @@ ngx_http_lua_inject_shdict_api(ngx_http_lua_main_conf_t *lmcf, lua_State *L)
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lua_pushcfunction(L, ngx_http_lua_shdict_llen);
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lua_setfield(L, -2, "llen");
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lua_pushcfunction(L, ngx_http_lua_shdict_lindex);
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lua_setfield(L, -2, "lindex");
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lua_pushcfunction(L, ngx_http_lua_shdict_flush_all);
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lua_setfield(L, -2, "flush_all");
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@@ -2176,6 +2180,165 @@ ngx_http_lua_shdict_llen(lua_State *L)
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}
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2183+
static int
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ngx_http_lua_shdict_lindex(lua_State *L)
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{
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int n, i, index;
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uint8_t value_type;
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uint32_t hash;
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double num;
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ngx_int_t rc;
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ngx_str_t name, key, value;
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ngx_queue_t *queue;
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ngx_http_lua_shdict_ctx_t *ctx;
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ngx_http_lua_shdict_node_t *sd;
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ngx_shm_zone_t *zone;
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ngx_http_lua_shdict_list_node_t *lnode;
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n = lua_gettop(L);
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if (n != 3) {
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return luaL_error(L, "expecting 3 arguments, "
2203+
"but only seen %d", n);
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}
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if (lua_type(L, 1) != LUA_TTABLE) {
2207+
return luaL_error(L, "bad \"zone\" argument");
2208+
}
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zone = ngx_http_lua_shdict_get_zone(L, 1);
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if (zone == NULL) {
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return luaL_error(L, "bad \"zone\" argument");
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}
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ctx = zone->data;
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name = ctx->name;
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2218+
if (lua_isnil(L, 2)) {
2219+
lua_pushnil(L);
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lua_pushliteral(L, "nil key");
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return 2;
2222+
}
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key.data = (u_char *) luaL_checklstring(L, 2, &key.len);
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if (key.len == 0) {
2227+
lua_pushnil(L);
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lua_pushliteral(L, "empty key");
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return 2;
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}
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if (key.len > 65535) {
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lua_pushnil(L);
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lua_pushliteral(L, "key too long");
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return 2;
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}
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index = luaL_checkint(L, 3);
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2240+
hash = ngx_crc32_short(key.data, key.len);
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ngx_shmtx_lock(&ctx->shpool->mutex);
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#if 1
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ngx_http_lua_shdict_expire(ctx, 1);
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#endif
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rc = ngx_http_lua_shdict_lookup(zone, hash, key.data, key.len, &sd);
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dd("shdict lookup returned %d", (int) rc);
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if (rc == NGX_DECLINED || rc == NGX_DONE) {
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ngx_shmtx_unlock(&ctx->shpool->mutex);
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lua_pushnil(L);
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return 1;
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}
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/* rc == NGX_OK */
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if (sd->value_type != SHDICT_TLIST) {
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ngx_shmtx_unlock(&ctx->shpool->mutex);
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lua_pushnil(L);
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lua_pushliteral(L, "value not a list");
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return 2;
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}
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ngx_queue_remove(&sd->queue);
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ngx_queue_insert_head(&ctx->sh->lru_queue, &sd->queue);
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if (index >= (int) sd->value_len || -index > (int) sd->value_len) {
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ngx_shmtx_unlock(&ctx->shpool->mutex);
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lua_pushnil(L);
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return 1;
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}
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queue = ngx_http_lua_shdict_get_list_head(sd, key.len);
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if (index >= 0) { /* forward */
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for (i = 0; i <= index; i++) {
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queue = ngx_queue_next(queue);
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}
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} else { /* backward */
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for (i = -1; i >= index; i--) {
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queue = ngx_queue_prev(queue);
2290+
}
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}
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lnode = ngx_queue_data(queue, ngx_http_lua_shdict_list_node_t, queue);
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value_type = lnode->value_type;
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dd("data: %p", lnode->data);
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dd("value len: %d", (int) sd->value_len);
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2300+
value.data = lnode->data;
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value.len = (size_t) lnode->value_len;
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switch (value_type) {
2304+
2305+
case SHDICT_TSTRING:
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2307+
lua_pushlstring(L, (char *) value.data, value.len);
2308+
break;
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2310+
case SHDICT_TNUMBER:
2311+
2312+
if (value.len != sizeof(double)) {
2313+
2314+
ngx_shmtx_unlock(&ctx->shpool->mutex);
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return luaL_error(L, "bad lua list node number value size found"
2317+
" for key %s in shared_dict %s: %lu",
2318+
key.data, name.data,
2319+
(unsigned long) value.len);
2320+
}
2321+
2322+
ngx_memcpy(&num, value.data, sizeof(double));
2323+
2324+
lua_pushnumber(L, num);
2325+
break;
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2327+
default:
2328+
2329+
ngx_shmtx_unlock(&ctx->shpool->mutex);
2330+
2331+
return luaL_error(L, "bad list node value type found for key %s in "
2332+
"shared_dict %s: %d", key.data, name.data,
2333+
value_type);
2334+
}
2335+
2336+
ngx_shmtx_unlock(&ctx->shpool->mutex);
2337+
2338+
return 1;
2339+
}
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ngx_shm_zone_t *
21802343
ngx_http_lua_find_zone(u_char *name_data, size_t name_len)
21812344
{

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