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|
//go:build darwin
package fuse
import (
"syscall"
"unsafe"
)
// File allocation support for macOS using fcntl
const (
// macOS doesn't have fallocate, but we can use fcntl with F_PREALLOCATE
F_ALLOCATECONTIG = 0x02
F_ALLOCATEALL = 0x04
// Dummy flags for compatibility
FALLOC_FL_KEEP_SIZE = 0x01
FALLOC_FL_PUNCH_HOLE = 0x02
FALLOC_FL_NO_HIDE_STALE = 0x04
FALLOC_FL_COLLAPSE_RANGE = 0x08
FALLOC_FL_ZERO_RANGE = 0x10
FALLOC_FL_INSERT_RANGE = 0x20
FALLOC_FL_UNSHARE_RANGE = 0x40
)
// fstore_t structure for F_PREALLOCATE
type fstore struct {
flags uint32
posmode int16
offset int64
length int64
bytesalloc int64
}
func fallocateFile(fd int, mode int, offset int64, length int64) error {
// On macOS, we use fcntl with F_PREALLOCATE
store := fstore{
flags: F_ALLOCATECONTIG,
posmode: syscall.F_PEOFPOSMODE, // Allocate from EOF
offset: 0,
length: length,
}
_, _, errno := syscall.Syscall(syscall.SYS_FCNTL,
uintptr(fd),
syscall.F_PREALLOCATE,
uintptr(unsafe.Pointer(&store)))
if errno != 0 {
// If contiguous allocation fails, try non-contiguous
store.flags = F_ALLOCATEALL
_, _, errno = syscall.Syscall(syscall.SYS_FCNTL,
uintptr(fd),
syscall.F_PREALLOCATE,
uintptr(unsafe.Pointer(&store)))
if errno != 0 {
return errno
}
}
// Set file size if not keeping size
if mode&FALLOC_FL_KEEP_SIZE == 0 {
return syscall.Ftruncate(fd, offset+length)
}
return nil
}
func isFallocateSupported() bool {
return true
}
|
