diff options
| -rw-r--r-- | libpod/lock/shm/shm_lock.go | 2 | ||||
| -rw-r--r-- | libpod/lock/shm/shm_lock_nocgo.go | 102 |
2 files changed, 104 insertions, 0 deletions
diff --git a/libpod/lock/shm/shm_lock.go b/libpod/lock/shm/shm_lock.go index 76dd5729e..37c8dea7d 100644 --- a/libpod/lock/shm/shm_lock.go +++ b/libpod/lock/shm/shm_lock.go @@ -1,3 +1,5 @@ +// +build linux,cgo + package shm // #cgo LDFLAGS: -lrt -lpthread diff --git a/libpod/lock/shm/shm_lock_nocgo.go b/libpod/lock/shm/shm_lock_nocgo.go new file mode 100644 index 000000000..ea1488c90 --- /dev/null +++ b/libpod/lock/shm/shm_lock_nocgo.go @@ -0,0 +1,102 @@ +// +build linux,!cgo + +package shm + +import ( + "github.com/sirupsen/logrus" +) + +// SHMLocks is a struct enabling POSIX semaphore locking in a shared memory +// segment. +type SHMLocks struct { +} + +// CreateSHMLock sets up a shared-memory segment holding a given number of POSIX +// semaphores, and returns a struct that can be used to operate on those locks. +// numLocks must not be 0, and may be rounded up to a multiple of the bitmap +// size used by the underlying implementation. +func CreateSHMLock(path string, numLocks uint32) (*SHMLocks, error) { + logrus.Error("locks are not supported without cgo") + return &SHMLocks{}, nil +} + +// OpenSHMLock opens an existing shared-memory segment holding a given number of +// POSIX semaphores. numLocks must match the number of locks the shared memory +// segment was created with. +func OpenSHMLock(path string, numLocks uint32) (*SHMLocks, error) { + logrus.Error("locks are not supported without cgo") + return &SHMLocks{}, nil +} + +// GetMaxLocks returns the maximum number of locks in the SHM +func (locks *SHMLocks) GetMaxLocks() uint32 { + logrus.Error("locks are not supported without cgo") + return 0 +} + +// Close closes an existing shared-memory segment. +// The segment will be rendered unusable after closing. +// WARNING: If you Close() while there are still locks locked, these locks may +// fail to release, causing a program freeze. +// Close() is only intended to be used while testing the locks. +func (locks *SHMLocks) Close() error { + logrus.Error("locks are not supported without cgo") + return nil +} + +// AllocateSemaphore allocates a semaphore from a shared-memory segment for use +// by a container or pod. +// Returns the index of the semaphore that was allocated. +// Allocations past the maximum number of locks given when the SHM segment was +// created will result in an error, and no semaphore will be allocated. +func (locks *SHMLocks) AllocateSemaphore() (uint32, error) { + logrus.Error("locks are not supported without cgo") + return 0, nil +} + +// AllocateGivenSemaphore allocates the given semaphore from the shared-memory +// segment for use by a container or pod. +// If the semaphore is already in use or the index is invalid an error will be +// returned. +func (locks *SHMLocks) AllocateGivenSemaphore(sem uint32) error { + logrus.Error("locks are not supported without cgo") + return nil +} + +// DeallocateSemaphore frees a semaphore in a shared-memory segment so it can be +// reallocated to another container or pod. +// The given semaphore must be already allocated, or an error will be returned. +func (locks *SHMLocks) DeallocateSemaphore(sem uint32) error { + logrus.Error("locks are not supported without cgo") + return nil +} + +// DeallocateAllSemaphores frees all semaphores so they can be reallocated to +// other containers and pods. +func (locks *SHMLocks) DeallocateAllSemaphores() error { + logrus.Error("locks are not supported without cgo") + return nil +} + +// LockSemaphore locks the given semaphore. +// If the semaphore is already locked, LockSemaphore will block until the lock +// can be acquired. +// There is no requirement that the given semaphore be allocated. +// This ensures that attempts to lock a container after it has been deleted, +// but before the caller has queried the database to determine this, will +// succeed. +func (locks *SHMLocks) LockSemaphore(sem uint32) error { + logrus.Error("locks are not supported without cgo") + return nil +} + +// UnlockSemaphore unlocks the given semaphore. +// Unlocking a semaphore that is already unlocked with return EBUSY. +// There is no requirement that the given semaphore be allocated. +// This ensures that attempts to lock a container after it has been deleted, +// but before the caller has queried the database to determine this, will +// succeed. +func (locks *SHMLocks) UnlockSemaphore(sem uint32) error { + logrus.Error("locks are not supported without cgo") + return nil +} |