Refactor.

ncruces · Nov 5, 2024 · 04af9fe · 04af9fe
1 parent ee15dec
commit 04af9fe
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Showing 6 changed files with 21 additions and 28 deletions.
diff --git a/internal/util/mmap.go b/internal/util/mmap.go
@@ -55,10 +55,10 @@ type MappedRegion struct {
 	used bool
 }
 
-func MapRegion(ctx context.Context, mod api.Module, f *os.File, offset int64, size int32, prot int) (*MappedRegion, error) {
+func MapRegion(ctx context.Context, mod api.Module, f *os.File, offset int64, size int32, readOnly bool) (*MappedRegion, error) {
 	s := ctx.Value(moduleKey{}).(*moduleState)
 	r := s.new(ctx, mod, size)
-	err := r.mmap(f, offset, prot)
+	err := r.mmap(f, offset, readOnly)
 	if err != nil {
 		return nil, err
 	}
@@ -75,7 +75,11 @@ func (r *MappedRegion) Unmap() error {
 	return err
 }
 
-func (r *MappedRegion) mmap(f *os.File, offset int64, prot int) error {
+func (r *MappedRegion) mmap(f *os.File, offset int64, readOnly bool) error {
+	prot := unix.PROT_READ
+	if !readOnly {
+		prot |= unix.PROT_WRITE
+	}
 	_, err := unix.MmapPtr(int(f.Fd()), offset, r.addr, uintptr(r.size),
 		prot, unix.MAP_SHARED|unix.MAP_FIXED)
 	r.used = err == nil

diff --git a/vfs/shm.go b/vfs/shm.go
@@ -1,4 +1,4 @@
-//go:build ((darwin || linux || freebsd || openbsd || netbsd || dragonfly || illumos) && (386 || arm || amd64 || arm64 || riscv64 || ppc64le) && !sqlite3_nosys) || sqlite3_flock || sqlite3_dotlk
+//go:build ((linux || darwin || freebsd || openbsd || netbsd || dragonfly || illumos) && (386 || arm || amd64 || arm64 || riscv64 || ppc64le) && !sqlite3_nosys) || sqlite3_flock || sqlite3_dotlk
 
 package vfs
 

diff --git a/vfs/shm_bsd.go b/vfs/shm_bsd.go
@@ -146,8 +146,7 @@ func (s *vfsShm) shmMap(ctx context.Context, mod api.Module, id, size int32, ext
 		}
 	}
 
-	r, err := util.MapRegion(ctx, mod, s.File, int64(id)*int64(size), size,
-		unix.PROT_READ|unix.PROT_WRITE)
+	r, err := util.MapRegion(ctx, mod, s.File, int64(id)*int64(size), size, false)
 	if err != nil {
 		return 0, _IOERR_SHMMAP
 	}

diff --git a/vfs/shm_dotlk.go b/vfs/shm_dotlk.go
@@ -14,8 +14,6 @@ import (
 	"github.com/tetratelabs/wazero/api"
 )
 
-const _WALINDEX_PGSZ = 32768
-
 type vfsShmBuffer struct {
 	shared []byte // +checklocks:Mutex
 	refs   int    // +checklocks:vfsShmBuffersMtx
@@ -151,7 +149,7 @@ func (s *vfsShm) shmLock(offset, n int32, flags _ShmFlag) _ErrorCode {
 
 	switch {
 	case flags&_SHM_LOCK != 0:
-		s.shmAcquire()
+		defer s.shmAcquire()
 	case flags&_SHM_EXCLUSIVE != 0:
 		s.shmRelease()
 	}
@@ -248,6 +246,8 @@ func (s *vfsShm) shmBarrier() {
 //
 // https://sqlite.org/walformat.html#the_wal_index_file_format
 
+const _WALINDEX_PGSZ = 32768
+
 // +checklocks:s.Mutex
 func (s *vfsShm) shmAcquire() {
 	// Copies modified words from shared to private memory.

diff --git a/vfs/shm_ofd.go b/vfs/shm_ofd.go
@@ -1,4 +1,4 @@
-//go:build (darwin || linux) && (386 || arm || amd64 || arm64 || riscv64 || ppc64le) && !(sqlite3_flock || sqlite3_dotlk || sqlite3_nosys)
+//go:build (linux || darwin) && (386 || arm || amd64 || arm64 || riscv64 || ppc64le) && !(sqlite3_flock || sqlite3_dotlk || sqlite3_nosys)
 
 package vfs
 
@@ -21,7 +21,7 @@ type vfsShm struct {
 	regions  []*util.MappedRegion
 	readOnly bool
 	blocking bool
-	barrier  sync.Mutex
+	sync.Mutex
 }
 
 var _ blockingSharedMemory = &vfsShm{}
@@ -32,7 +32,7 @@ func (s *vfsShm) shmOpen() _ErrorCode {
 			unix.O_RDWR|unix.O_CREAT|unix.O_NOFOLLOW, 0666)
 		if err != nil {
 			f, err = os.OpenFile(s.path,
-				unix.O_CREAT|unix.O_NOFOLLOW, 0666)
+				unix.O_RDONLY|unix.O_CREAT|unix.O_NOFOLLOW, 0666)
 			s.readOnly = true
 		}
 		if err != nil {
@@ -64,10 +64,7 @@ func (s *vfsShm) shmOpen() _ErrorCode {
 			return _IOERR_SHMOPEN
 		}
 	}
-	if rc := osReadLock(s.File, _SHM_DMS, 1, time.Millisecond); rc != _OK {
-		return rc
-	}
-	return _OK
+	return osReadLock(s.File, _SHM_DMS, 1, time.Millisecond)
 }
 
 func (s *vfsShm) shmMap(ctx context.Context, mod api.Module, id, size int32, extend bool) (uint32, _ErrorCode) {
@@ -94,13 +91,7 @@ func (s *vfsShm) shmMap(ctx context.Context, mod api.Module, id, size int32, ext
 		}
 	}
 
-	var prot int
-	if s.readOnly {
-		prot = unix.PROT_READ
-	} else {
-		prot = unix.PROT_READ | unix.PROT_WRITE
-	}
-	r, err := util.MapRegion(ctx, mod, s.File, int64(id)*int64(size), size, prot)
+	r, err := util.MapRegion(ctx, mod, s.File, int64(id)*int64(size), size, s.readOnly)
 	if err != nil {
 		return 0, _IOERR_SHMMAP
 	}
@@ -156,8 +147,7 @@ func (s *vfsShm) shmUnmap(delete bool) {
 	for _, r := range s.regions {
 		r.Unmap()
 	}
-	clear(s.regions)
-	s.regions = s.regions[:0]
+	s.regions = nil
 
 	// Close the file.
 	if delete {
@@ -168,9 +158,9 @@ func (s *vfsShm) shmUnmap(delete bool) {
 }
 
 func (s *vfsShm) shmBarrier() {
-	s.barrier.Lock()
+	s.Lock()
 	//lint:ignore SA2001 memory barrier.
-	s.barrier.Unlock()
+	s.Unlock()
 }
 
 func (s *vfsShm) shmEnableBlocking(block bool) {

diff --git a/vfs/shm_other.go b/vfs/shm_other.go
@@ -1,4 +1,4 @@
-//go:build !(((darwin || linux || freebsd || openbsd || netbsd || dragonfly || illumos) && (386 || arm || amd64 || arm64 || riscv64 || ppc64le) && !sqlite3_nosys) || sqlite3_flock || sqlite3_dotlk)
+//go:build !(((linux || darwin || freebsd || openbsd || netbsd || dragonfly || illumos) && (386 || arm || amd64 || arm64 || riscv64 || ppc64le) && !sqlite3_nosys) || sqlite3_flock || sqlite3_dotlk)
 
 package vfs