Struct __wt_collator 

#[repr(C)]
pub struct __wt_collator {
    pub compare: Option<unsafe extern "C" fn(collator: *mut WT_COLLATOR, session: *mut WT_SESSION, key1: *const WT_ITEM, key2: *const WT_ITEM, cmp: *mut c_int) -> c_int>,
    pub customize: Option<unsafe extern "C" fn(collator: *mut WT_COLLATOR, session: *mut WT_SESSION, uri: *const c_char, passcfg: *mut WT_CONFIG_ITEM, customp: *mut *mut WT_COLLATOR) -> c_int>,
    pub terminate: Option<unsafe extern "C" fn(collator: *mut WT_COLLATOR, session: *mut WT_SESSION) -> c_int>,
}

The interface implemented by applications to provide custom ordering of records.

Applications register their implementation with WiredTiger by calling WT_CONNECTION::add_collator. See @ref custom_collators for more information.

@snippet ex_extending.c add collator nocase

@snippet ex_extending.c add collator prefix10

Fields

compare: Option<unsafe extern "C" fn(collator: *mut WT_COLLATOR, session: *mut WT_SESSION, key1: *const WT_ITEM, key2: *const WT_ITEM, cmp: *mut c_int) -> c_int>

Callback to compare keys.

@param[out] cmp set to -1 if key1 < key2, 0 if key1 == key2, 1 if key1 > key2. @returns zero for success, non-zero to indicate an error.

@snippet ex_all.c Implement WT_COLLATOR

@snippet ex_extending.c case insensitive comparator

@snippet ex_extending.c n character comparator

customize: Option<unsafe extern "C" fn(collator: *mut WT_COLLATOR, session: *mut WT_SESSION, uri: *const c_char, passcfg: *mut WT_CONFIG_ITEM, customp: *mut *mut WT_COLLATOR) -> c_int>

If non-NULL, this callback is called to customize the collator for each data source. If the callback returns a non-NULL collator, that instance is used instead of this one for all comparisons.

terminate: Option<unsafe extern "C" fn(collator: *mut WT_COLLATOR, session: *mut WT_SESSION) -> c_int>

If non-NULL a callback performed when the data source is closed for customized extractors otherwise when the database is closed.

The WT_COLLATOR::terminate callback is intended to allow cleanup, the handle will not be subsequently accessed by WiredTiger.

Trait Implementations

impl Clone for __wt_collator

fn clone(&self) -> __wt_collator

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for __wt_collator

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Copy for __wt_collator