Apache HTTP Server 2.4 版
說明 | 基於槽的共用記憶體供應器。 |
---|---|
狀態 | 擴充模組 |
模組識別碼 | slotmem_shm_module |
原始檔 | mod_slotmem_shm.c |
mod_slotmem_shm
是用來在共用記憶體區段(資料集在其中以「槽」組織)進行建立跟存取的記憶體供應器。
所有共用記憶體都會在每次重新啟動時被清除並清理,無論是否為正常重新啟動。資料本身會儲存在 create
和 attach
呼叫中 name
參數所指定的檔案中,並會從該檔案中還原。如果沒有指定絕對路徑,則檔案會相對於 DefaultRuntimeDir
指令所指定的的路徑建立。
mod_slotmem_shm
提供下列 API 函數
/* call the callback on all worker slots */ apr_status_t doall(ap_slotmem_instance_t *s, ap_slotmem_callback_fn_t *func, void *data, apr_pool_t *pool) /* create a new slotmem with each item size is item_size. 'name' is used to generate a filename for the persistent store of the shared memory if configured. Values are: "none" - Anonymous shared memory and no persistent store "file-name" - [DefaultRuntimeDir]/file-name "/absolute-file-name" - Absolute file name */ apr_status_t create(ap_slotmem_instance_t **new, const char *name, apr_size_t item_size, unsigned int item_num, ap_slotmem_type_t type, apr_pool_t *pool) /* attach to an existing slotmem. See 'create()' for description of 'name' parameter */ apr_status_t attach(ap_slotmem_instance_t **new, const char *name, apr_size_t *item_size, unsigned int *item_num, apr_pool_t *pool) /* get the direct pointer to the memory associated with this worker slot */ apr_status_t dptr(ap_slotmem_instance_t *s, unsigned int item_id, void **mem) /* get/read the memory from this slot to dest */ apr_status_t get(ap_slotmem_instance_t *s, unsigned int item_id, unsigned char *dest, apr_size_t dest_len) /* put/write the data from src to this slot */ apr_status_t put(ap_slotmem_instance_t *slot, unsigned int item_id, unsigned char *src, apr_size_t src_len) /* return the total number of slots in the segment */ unsigned int num_slots(ap_slotmem_instance_t *s) /* return the total data size, in bytes, of a slot in the segment */ apr_size_t slot_size(ap_slotmem_instance_t *s) /* grab or allocate the first free slot and mark as in-use (does not do any data copying) */ apr_status_t grab(ap_slotmem_instance_t *s, unsigned int *item_id) /* forced grab or allocate the specified slot and mark as in-use (does not do any data copying) */ apr_status_t fgrab(ap_slotmem_instance_t *s, unsigned int item_id) /* release or free a slot and mark as not in-use (does not do any data copying) */ apr_status_t release(ap_slotmem_instance_t *s, unsigned int item_id)