mdbx: добавление mdbx_cursor_on_first/last_dup() в API.

This commit is contained in:
Леонид Юрьев (Leonid Yuriev) 2023-11-18 02:34:07 +03:00
parent eee3e6eb6b
commit ed59ad22c6
3 changed files with 65 additions and 0 deletions

8
mdbx.h
View File

@ -5138,6 +5138,10 @@ mdbx_cursor_eof(const MDBX_cursor *cursor);
MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
mdbx_cursor_on_first(const MDBX_cursor *cursor);
/** FIXME */
MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
mdbx_cursor_on_first_dup(const MDBX_cursor *cursor);
/** \brief Determines whether the cursor is pointed to the last key-value pair
* or not.
* \ingroup c_cursors
@ -5152,6 +5156,10 @@ mdbx_cursor_on_first(const MDBX_cursor *cursor);
MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
mdbx_cursor_on_last(const MDBX_cursor *cursor);
/** FIXME */
MDBX_NOTHROW_PURE_FUNCTION LIBMDBX_API int
mdbx_cursor_on_last_dup(const MDBX_cursor *cursor);
/** \addtogroup c_rqest
* \details \note The estimation result varies greatly depending on the filling
* of specific pages and the overall balance of the b-tree:

View File

@ -4467,6 +4467,8 @@ public:
inline bool eof() const;
inline bool on_first() const;
inline bool on_last() const;
inline bool on_first_multival() const;
inline bool on_last_multival() const;
inline estimate_result estimate(const slice &key, const slice &value) const;
inline estimate_result estimate(const slice &key) const;
inline estimate_result estimate(move_operation operation) const;
@ -6396,6 +6398,14 @@ inline bool cursor::on_last() const {
return error::boolean_or_throw(::mdbx_cursor_on_last(*this));
}
inline bool cursor::on_first_multival() const {
return error::boolean_or_throw(::mdbx_cursor_on_first_dup(*this));
}
inline bool cursor::on_last_multival() const {
return error::boolean_or_throw(::mdbx_cursor_on_last_dup(*this));
}
inline cursor::estimate_result cursor::estimate(const slice &key,
const slice &value) const {
return estimate_result(*this, multi_exactkey_lowerboundvalue, key, value);

View File

@ -24533,6 +24533,29 @@ int mdbx_cursor_on_first(const MDBX_cursor *mc) {
return MDBX_RESULT_TRUE;
}
int mdbx_cursor_on_first_dup(const MDBX_cursor *mc) {
if (unlikely(mc == NULL))
return MDBX_EINVAL;
if (unlikely(mc->mc_signature != MDBX_MC_LIVE))
return (mc->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
: MDBX_EBADSIGN;
if (!(mc->mc_flags & C_INITIALIZED))
return mc->mc_db->md_entries ? MDBX_RESULT_FALSE : MDBX_RESULT_TRUE;
if (!mc->mc_xcursor)
return MDBX_RESULT_TRUE;
mc = &mc->mc_xcursor->mx_cursor;
for (size_t i = 0; i < mc->mc_snum; ++i) {
if (mc->mc_ki[i])
return MDBX_RESULT_FALSE;
}
return MDBX_RESULT_TRUE;
}
int mdbx_cursor_on_last(const MDBX_cursor *mc) {
if (unlikely(mc == NULL))
return MDBX_EINVAL;
@ -24553,6 +24576,30 @@ int mdbx_cursor_on_last(const MDBX_cursor *mc) {
return MDBX_RESULT_TRUE;
}
int mdbx_cursor_on_last_dup(const MDBX_cursor *mc) {
if (unlikely(mc == NULL))
return MDBX_EINVAL;
if (unlikely(mc->mc_signature != MDBX_MC_LIVE))
return (mc->mc_signature == MDBX_MC_READY4CLOSE) ? MDBX_EINVAL
: MDBX_EBADSIGN;
if (!(mc->mc_flags & C_INITIALIZED))
return mc->mc_db->md_entries ? MDBX_RESULT_FALSE : MDBX_RESULT_TRUE;
if (!mc->mc_xcursor)
return MDBX_RESULT_TRUE;
mc = &mc->mc_xcursor->mx_cursor;
for (size_t i = 0; i < mc->mc_snum; ++i) {
size_t nkeys = page_numkeys(mc->mc_pg[i]);
if (mc->mc_ki[i] < nkeys - 1)
return MDBX_RESULT_FALSE;
}
return MDBX_RESULT_TRUE;
}
int mdbx_cursor_eof(const MDBX_cursor *mc) {
if (unlikely(mc == NULL))
return MDBX_EINVAL;