gotosocial/vendor/github.com/ncruces/go-sqlite3/internal/util/handle.go
kim 1e7b32490d
[experiment] add alternative wasm sqlite3 implementation available via build-tag (#2863)
This allows for building GoToSocial with [SQLite transpiled to WASM](https://github.com/ncruces/go-sqlite3) and accessed through [Wazero](https://wazero.io/).
2024-05-27 17:46:15 +02:00

66 lines
1.1 KiB
Go

package util
import (
"context"
"io"
)
type handleState struct {
handles []any
holes int
}
func (s *handleState) CloseNotify(ctx context.Context, exitCode uint32) {
for _, h := range s.handles {
if c, ok := h.(io.Closer); ok {
c.Close()
}
}
s.handles = nil
s.holes = 0
}
func GetHandle(ctx context.Context, id uint32) any {
if id == 0 {
return nil
}
s := ctx.Value(moduleKey{}).(*moduleState)
return s.handles[^id]
}
func DelHandle(ctx context.Context, id uint32) error {
if id == 0 {
return nil
}
s := ctx.Value(moduleKey{}).(*moduleState)
a := s.handles[^id]
s.handles[^id] = nil
s.holes++
if c, ok := a.(io.Closer); ok {
return c.Close()
}
return nil
}
func AddHandle(ctx context.Context, a any) (id uint32) {
if a == nil {
panic(NilErr)
}
s := ctx.Value(moduleKey{}).(*moduleState)
// Find an empty slot.
if s.holes > cap(s.handles)-len(s.handles) {
for id, h := range s.handles {
if h == nil {
s.holes--
s.handles[id] = a
return ^uint32(id)
}
}
}
// Add a new slot.
s.handles = append(s.handles, a)
return -uint32(len(s.handles))
}