Add ngx_http_lua_ffi_shdict_store_when for set_when and safe_set_when

README.markdown

@@ -3261,6 +3261,8 @@ Nginx API for Lua
 * [ngx.shared.DICT.get_stale](#ngxshareddictget_stale)
 * [ngx.shared.DICT.set](#ngxshareddictset)
 * [ngx.shared.DICT.safe_set](#ngxshareddictsafe_set)
+* [ngx.shared.DICT.set_when](#ngxshareddictset_when)
+* [ngx.shared.DICT.safe_set_when](#ngxshareddictsafe_set_when)
 * [ngx.shared.DICT.add](#ngxshareddictadd)
 * [ngx.shared.DICT.safe_add](#ngxshareddictsafe_add)
 * [ngx.shared.DICT.replace](#ngxshareddictreplace)
@@ -6400,6 +6402,8 @@ The resulting object `dict` has the following methods:
 * [get_stale](#ngxshareddictget_stale)
 * [set](#ngxshareddictset)
 * [safe_set](#ngxshareddictsafe_set)
+* [set_when](#ngxshareddictset_when)
+* [safe_set_when](#ngxshareddictsafe_set_when)
 * [add](#ngxshareddictadd)
 * [safe_add](#ngxshareddictsafe_add)
 * [replace](#ngxshareddictreplace)
@@ -6590,6 +6594,42 @@ See also [ngx.shared.DICT](#ngxshareddict).
 
 [Back to TOC](#nginx-api-for-lua)
 
+ngx.shared.DICT.set_when
+------------------------
+**syntax:** *success, err, forcible = ngx.shared.DICT:set(key, old_value, value, exptime?, flags?)*
+
+**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**
+
+Just like the [set](#ngxshareddictset) method, but only stores the key-value pair into the dictionary [ngx.shared.DICT](#ngxshareddict) if the value for key is the same as `old_value`.
+
+If the `key` argument does *not* exist in the dictionary (or expired already), the `success` return value will be `true`.
+
+If the value for the key is *not* the same as `old_value`, the `success` return value will be `false` and the `err` value will be `"already modified"`.
+
+This feature was first introduced in the `v0.10.16rc1` release.
+
+See also [ngx.shared.DICT](#ngxshareddict).
+
+[Back to TOC](#nginx-api-for-lua)
+
+ngx.shared.DICT.safe_set_when
+-----------------------------
+**syntax:** *ok, err = ngx.shared.DICT:safe_set_when(key, old_value, value, exptime?, flags?)*
+
+**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**
+
+Similar to the [set_when](#ngxshareddictset_when) method, but never overrides the (least recently used) unexpired items in the store when running out of storage in the shared memory zone. In this case, it will immediately return `nil` and the string "no memory".
+
+If the `key` argument does *not* exist in the dictionary (or expired already), the `success` return value will be `true`.
+
+If the value for the key is *not* the same as `old_value`, the `success` return value will be `false` and the `err` value will be `"already modified"`.
+
+This feature was first introduced in the `v0.10.16rc1` release.
+
+See also [ngx.shared.DICT](#ngxshareddict).
+
+[Back to TOC](#nginx-api-for-lua)
+
 ngx.shared.DICT.add
 -------------------
 

doc/HttpLuaModule.wiki

@@ -5393,6 +5393,8 @@ The resulting object <code>dict</code> has the following methods:
 * [[#ngx.shared.DICT.get_stale|get_stale]]
 * [[#ngx.shared.DICT.set|set]]
 * [[#ngx.shared.DICT.safe_set|safe_set]]
+* [[#ngx.shared.DICT.set_when|set_when]]
+* [[#ngx.shared.DICT.safe_set_when|safe_set_when]]
 * [[#ngx.shared.DICT.add|add]]
 * [[#ngx.shared.DICT.safe_add|safe_add]]
 * [[#ngx.shared.DICT.replace|replace]]
@@ -5563,6 +5565,36 @@ This feature was first introduced in the <code>v0.7.18</code> release.
 
 See also [[#ngx.shared.DICT|ngx.shared.DICT]].
 
+== ngx.shared.DICT.set_when ==
+'''syntax:''' ''success, err, forcible = ngx.shared.DICT:set(key, old_value, value, exptime?, flags?)''
+
+'''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*''
+
+Just like the [[#ngx.shared.DICT.set|set]] method, but only stores the key-value pair into the dictionary [[#ngx.shared.DICT|ngx.shared.DICT]] if the value for key is the same as <code>old_value</code>.
+
+If the <code>key</code> argument does ''not'' exist in the dictionary (or expired already), the <code>success</code> return value will be <code>true</code>.
+
+If the value for the key is ''not'' the same as <code>old_value</code>, the <code>success</code> return value will be <code>false</code> and the <code>err</code> value will be <code>"already modified"</code>.
+
+This feature was first introduced in the <code>v0.10.16rc1</code> release.
+
+See also [[#ngx.shared.DICT|ngx.shared.DICT]].
+
+== ngx.shared.DICT.safe_set_when ==
+'''syntax:''' ''ok, err = ngx.shared.DICT:safe_set_when(key, old_value, value, exptime?, flags?)''
+
+'''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*''
+
+Similar to the [[#ngx.shared.DICT.set_when|set_when]] method, but never overrides the (least recently used) unexpired items in the store when running out of storage in the shared memory zone. In this case, it will immediately return <code>nil</code> and the string "no memory".
+
+If the <code>key</code> argument does ''not'' exist in the dictionary (or expired already), the <code>success</code> return value will be <code>true</code>.
+
+If the value for the key is ''not'' the same as <code>old_value</code>, the <code>success</code> return value will be <code>false</code> and the <code>err</code> value will be <code>"already modified"</code>.
+
+This feature was first introduced in the <code>v0.10.16rc1</code> release.
+
+See also [[#ngx.shared.DICT|ngx.shared.DICT]].
+
 == ngx.shared.DICT.add ==
 
 '''syntax:''' ''success, err, forcible = ngx.shared.DICT:add(key, value, exptime?, flags?)''