diff options
Diffstat (limited to 'sqlite3.go')
| -rw-r--r-- | sqlite3.go | 25 |
1 files changed, 25 insertions, 0 deletions
@@ -100,6 +100,8 @@ int _sqlite3_create_function( } void callbackTrampoline(sqlite3_context*, int, sqlite3_value**); + +int compareTrampoline(void*, int, char*, int, char*); */ import "C" import ( @@ -313,6 +315,29 @@ func (tx *SQLiteTx) Rollback() error { return err } +// RegisterCollation makes a Go function available as a collation. +// +// cmp receives two UTF-8 strings, a and b. The result should be 0 if +// a==b, -1 if a < b, and +1 if a > b. +// +// cmp must always return the same result given the same +// inputs. Additionally, it must have the following properties for all +// strings A, B and C: if A==B then B==A; if A==B and B==C then A==C; +// if A<B then B>A; if A<B and B<C then A<C. +// +// If cmp does not obey these constraints, sqlite3's behavior is +// undefined when the collation is used. +func (c *SQLiteConn) RegisterCollation(name string, cmp func(string, string) int) error { + handle := newHandle(c, cmp) + cname := C.CString(name) + defer C.free(unsafe.Pointer(cname)) + rv := C.sqlite3_create_collation(c.db, cname, C.SQLITE_UTF8, unsafe.Pointer(handle), (*[0]byte)(unsafe.Pointer(C.compareTrampoline))) + if rv != C.SQLITE_OK { + return c.lastError() + } + return nil +} + // RegisterFunc makes a Go function available as a SQLite function. // // The Go function can have arguments of the following types: any |