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-rw-r--r--vendor/github.com/boltdb/bolt/bolt_windows.go144
1 files changed, 144 insertions, 0 deletions
diff --git a/vendor/github.com/boltdb/bolt/bolt_windows.go b/vendor/github.com/boltdb/bolt/bolt_windows.go
new file mode 100644
index 000000000..b00fb0720
--- /dev/null
+++ b/vendor/github.com/boltdb/bolt/bolt_windows.go
@@ -0,0 +1,144 @@
+package bolt
+
+import (
+ "fmt"
+ "os"
+ "syscall"
+ "time"
+ "unsafe"
+)
+
+// LockFileEx code derived from golang build filemutex_windows.go @ v1.5.1
+var (
+ modkernel32 = syscall.NewLazyDLL("kernel32.dll")
+ procLockFileEx = modkernel32.NewProc("LockFileEx")
+ procUnlockFileEx = modkernel32.NewProc("UnlockFileEx")
+)
+
+const (
+ lockExt = ".lock"
+
+ // see https://msdn.microsoft.com/en-us/library/windows/desktop/aa365203(v=vs.85).aspx
+ flagLockExclusive = 2
+ flagLockFailImmediately = 1
+
+ // see https://msdn.microsoft.com/en-us/library/windows/desktop/ms681382(v=vs.85).aspx
+ errLockViolation syscall.Errno = 0x21
+)
+
+func lockFileEx(h syscall.Handle, flags, reserved, locklow, lockhigh uint32, ol *syscall.Overlapped) (err error) {
+ r, _, err := procLockFileEx.Call(uintptr(h), uintptr(flags), uintptr(reserved), uintptr(locklow), uintptr(lockhigh), uintptr(unsafe.Pointer(ol)))
+ if r == 0 {
+ return err
+ }
+ return nil
+}
+
+func unlockFileEx(h syscall.Handle, reserved, locklow, lockhigh uint32, ol *syscall.Overlapped) (err error) {
+ r, _, err := procUnlockFileEx.Call(uintptr(h), uintptr(reserved), uintptr(locklow), uintptr(lockhigh), uintptr(unsafe.Pointer(ol)), 0)
+ if r == 0 {
+ return err
+ }
+ return nil
+}
+
+// fdatasync flushes written data to a file descriptor.
+func fdatasync(db *DB) error {
+ return db.file.Sync()
+}
+
+// flock acquires an advisory lock on a file descriptor.
+func flock(db *DB, mode os.FileMode, exclusive bool, timeout time.Duration) error {
+ // Create a separate lock file on windows because a process
+ // cannot share an exclusive lock on the same file. This is
+ // needed during Tx.WriteTo().
+ f, err := os.OpenFile(db.path+lockExt, os.O_CREATE, mode)
+ if err != nil {
+ return err
+ }
+ db.lockfile = f
+
+ var t time.Time
+ for {
+ // If we're beyond our timeout then return an error.
+ // This can only occur after we've attempted a flock once.
+ if t.IsZero() {
+ t = time.Now()
+ } else if timeout > 0 && time.Since(t) > timeout {
+ return ErrTimeout
+ }
+
+ var flag uint32 = flagLockFailImmediately
+ if exclusive {
+ flag |= flagLockExclusive
+ }
+
+ err := lockFileEx(syscall.Handle(db.lockfile.Fd()), flag, 0, 1, 0, &syscall.Overlapped{})
+ if err == nil {
+ return nil
+ } else if err != errLockViolation {
+ return err
+ }
+
+ // Wait for a bit and try again.
+ time.Sleep(50 * time.Millisecond)
+ }
+}
+
+// funlock releases an advisory lock on a file descriptor.
+func funlock(db *DB) error {
+ err := unlockFileEx(syscall.Handle(db.lockfile.Fd()), 0, 1, 0, &syscall.Overlapped{})
+ db.lockfile.Close()
+ os.Remove(db.path + lockExt)
+ return err
+}
+
+// mmap memory maps a DB's data file.
+// Based on: https://github.com/edsrzf/mmap-go
+func mmap(db *DB, sz int) error {
+ if !db.readOnly {
+ // Truncate the database to the size of the mmap.
+ if err := db.file.Truncate(int64(sz)); err != nil {
+ return fmt.Errorf("truncate: %s", err)
+ }
+ }
+
+ // Open a file mapping handle.
+ sizelo := uint32(sz >> 32)
+ sizehi := uint32(sz) & 0xffffffff
+ h, errno := syscall.CreateFileMapping(syscall.Handle(db.file.Fd()), nil, syscall.PAGE_READONLY, sizelo, sizehi, nil)
+ if h == 0 {
+ return os.NewSyscallError("CreateFileMapping", errno)
+ }
+
+ // Create the memory map.
+ addr, errno := syscall.MapViewOfFile(h, syscall.FILE_MAP_READ, 0, 0, uintptr(sz))
+ if addr == 0 {
+ return os.NewSyscallError("MapViewOfFile", errno)
+ }
+
+ // Close mapping handle.
+ if err := syscall.CloseHandle(syscall.Handle(h)); err != nil {
+ return os.NewSyscallError("CloseHandle", err)
+ }
+
+ // Convert to a byte array.
+ db.data = ((*[maxMapSize]byte)(unsafe.Pointer(addr)))
+ db.datasz = sz
+
+ return nil
+}
+
+// munmap unmaps a pointer from a file.
+// Based on: https://github.com/edsrzf/mmap-go
+func munmap(db *DB) error {
+ if db.data == nil {
+ return nil
+ }
+
+ addr := (uintptr)(unsafe.Pointer(&db.data[0]))
+ if err := syscall.UnmapViewOfFile(addr); err != nil {
+ return os.NewSyscallError("UnmapViewOfFile", err)
+ }
+ return nil
+}