4 files changed, 109 insertions, 7 deletions

diff --git a/libpod/lock/shm/shm_lock.c b/libpod/lock/shm/shm_lock.c
index 047d3c417..fbb3f57cc 100644
--- a/libpod/lock/shm/shm_lock.c
+++ b/libpod/lock/shm/shm_lock.c
@@ -413,7 +413,7 @@ int32_t allocate_given_semaphore(shm_struct_t *shm, uint32_t sem_index) {
 // Returns 0 on success, negative ERRNO values on failure
 int32_t deallocate_semaphore(shm_struct_t *shm, uint32_t sem_index) {
   bitmap_t test_map;
-  int bitmap_index, index_in_bitmap, ret_code, i;
+  int bitmap_index, index_in_bitmap, ret_code;
 
   if (shm == NULL) {
     return -1 * EINVAL;
@@ -500,7 +500,7 @@ int32_t deallocate_all_semaphores(shm_struct_t *shm) {
 // subsequently realize they have been removed).
 // Returns 0 on success, -1 on failure
 int32_t lock_semaphore(shm_struct_t *shm, uint32_t sem_index) {
-  int bitmap_index, index_in_bitmap, ret_code;
+  int bitmap_index, index_in_bitmap;
 
   if (shm == NULL) {
     return -1 * EINVAL;
@@ -522,7 +522,7 @@ int32_t lock_semaphore(shm_struct_t *shm, uint32_t sem_index) {
 // subsequently realize they have been removed).
 // Returns 0 on success, -1 on failure
 int32_t unlock_semaphore(shm_struct_t *shm, uint32_t sem_index) {
-  int bitmap_index, index_in_bitmap, ret_code;
+  int bitmap_index, index_in_bitmap;
 
   if (shm == NULL) {
     return -1 * EINVAL;
diff --git a/libpod/lock/shm/shm_lock.go b/libpod/lock/shm/shm_lock.go
index c21e9a221..322e92a8f 100644
--- a/libpod/lock/shm/shm_lock.go
+++ b/libpod/lock/shm/shm_lock.go
@@ -1,6 +1,9 @@
+// +build linux,cgo
+
 package shm
 
 // #cgo LDFLAGS: -lrt -lpthread
+// #cgo CFLAGS: -Wall -Werror
 // #include <stdlib.h>
 // #include "shm_lock.h"
 // const uint32_t bitmap_size_c = BITMAP_SIZE;
@@ -19,7 +22,7 @@ var (
 	// BitmapSize is the size of the bitmap used when managing SHM locks.
 	// an SHM lock manager's max locks will be rounded up to a multiple of
 	// this number.
-	BitmapSize uint32 = uint32(C.bitmap_size_c)
+	BitmapSize = uint32(C.bitmap_size_c)
 )
 
 // SHMLocks is a struct enabling POSIX semaphore locking in a shared memory
diff --git a/libpod/lock/shm/shm_lock.h b/libpod/lock/shm/shm_lock.h
index 759f8178a..8796b43f4 100644
--- a/libpod/lock/shm/shm_lock.h
+++ b/libpod/lock/shm/shm_lock.h
@@ -32,9 +32,6 @@ typedef struct shm_struct {
   lock_group_t    locks[];
 } shm_struct_t;
 
-static size_t compute_shm_size(uint32_t num_bitmaps);
-static int take_mutex(pthread_mutex_t *mutex);
-static int release_mutex(pthread_mutex_t *mutex);
 shm_struct_t *setup_lock_shm(char *path, uint32_t num_locks, int *error_code);
 shm_struct_t *open_lock_shm(char *path, uint32_t num_locks, int *error_code);
 int32_t close_lock_shm(shm_struct_t *shm);
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
+}