[chore] Update ncruces/go-sqlite3 to 0.21.3 (#3629)

This includes some additional locking fixes for the BSDs.

1 files changed, 7 insertions, 9 deletions

diff --git a/vendor/github.com/ncruces/go-sqlite3/vfs/shm_memlk.go b/vendor/github.com/ncruces/go-sqlite3/vfs/shm_memlk.go
index 404019642..5c8071ebe 100644
--- a/vendor/github.com/ncruces/go-sqlite3/vfs/shm_memlk.go
+++ b/vendor/github.com/ncruces/go-sqlite3/vfs/shm_memlk.go
@@ -10,9 +10,6 @@ func (s *vfsShm) shmMemLock(offset, n int32, flags _ShmFlag) _ErrorCode {
 	case flags&_SHM_UNLOCK != 0:
 		for i := offset; i < offset+n; i++ {
 			if s.lock[i] {
-				if s.vfsShmParent.lock[i] == 0 {
-					panic(util.AssertErr())
-				}
 				if s.vfsShmParent.lock[i] <= 0 {
 					s.vfsShmParent.lock[i] = 0
 				} else {
@@ -23,20 +20,21 @@ func (s *vfsShm) shmMemLock(offset, n int32, flags _ShmFlag) _ErrorCode {
 		}
 	case flags&_SHM_SHARED != 0:
 		for i := offset; i < offset+n; i++ {
-			if s.lock[i] {
-				panic(util.AssertErr())
-			}
-			if s.vfsShmParent.lock[i]+1 <= 0 {
+			if !s.lock[i] &&
+				s.vfsShmParent.lock[i]+1 <= 0 {
 				return _BUSY
 			}
 		}
 		for i := offset; i < offset+n; i++ {
-			s.vfsShmParent.lock[i]++
-			s.lock[i] = true
+			if !s.lock[i] {
+				s.vfsShmParent.lock[i]++
+				s.lock[i] = true
+			}
 		}
 	case flags&_SHM_EXCLUSIVE != 0:
 		for i := offset; i < offset+n; i++ {
 			if s.lock[i] {
+				// SQLite never requests an exclusive lock that it already holds.
 				panic(util.AssertErr())
 			}
 			if s.vfsShmParent.lock[i] != 0 {