1 files changed, 243 insertions, 0 deletions
diff --git a/vendor/git.iim.gay/grufwub/go-store/kv/store.go b/vendor/git.iim.gay/grufwub/go-store/kv/store.go
new file mode 100644
index 000000000..840a554e9
--- /dev/null
+++ b/vendor/git.iim.gay/grufwub/go-store/kv/store.go
@@ -0,0 +1,243 @@
+package kv
+
+import (
+	"io"
+	"sync"
+
+	"git.iim.gay/grufwub/go-mutexes"
+	"git.iim.gay/grufwub/go-store/storage"
+	"git.iim.gay/grufwub/go-store/util"
+)
+
+// KVStore is a very simple, yet performant key-value store
+type KVStore struct {
+	mutexMap mutexes.MutexMap // mutexMap is a map of keys to mutexes to protect file access
+	mutex    sync.RWMutex     // mutex is the total store mutex
+	storage  storage.Storage  // storage is the underlying storage
+}
+
+func OpenFile(path string, cfg *storage.DiskConfig) (*KVStore, error) {
+	// Attempt to open disk storage
+	storage, err := storage.OpenFile(path, cfg)
+	if err != nil {
+		return nil, err
+	}
+
+	// Return new KVStore
+	return OpenStorage(storage)
+}
+
+func OpenBlock(path string, cfg *storage.BlockConfig) (*KVStore, error) {
+	// Attempt to open block storage
+	storage, err := storage.OpenBlock(path, cfg)
+	if err != nil {
+		return nil, err
+	}
+
+	// Return new KVStore
+	return OpenStorage(storage)
+}
+
+func OpenStorage(storage storage.Storage) (*KVStore, error) {
+	// Perform initial storage clean
+	err := storage.Clean()
+	if err != nil {
+		return nil, err
+	}
+
+	// Return new KVStore
+	return &KVStore{
+		mutexMap: mutexes.NewMap(mutexes.NewRW),
+		mutex:    sync.RWMutex{},
+		storage:  storage,
+	}, nil
+}
+
+// Get fetches the bytes for supplied key in the store
+func (st *KVStore) Get(key string) ([]byte, error) {
+	// Acquire store read lock
+	st.mutex.RLock()
+	defer st.mutex.RUnlock()
+
+	// Pass to unprotected fn
+	return st.get(key)
+}
+
+func (st *KVStore) get(key string) ([]byte, error) {
+	// Acquire read lock for key
+	runlock := st.mutexMap.RLock(key)
+	defer runlock()
+
+	// Read file bytes
+	return st.storage.ReadBytes(key)
+}
+
+// GetStream fetches a ReadCloser for the bytes at the supplied key location in the store
+func (st *KVStore) GetStream(key string) (io.ReadCloser, error) {
+	// Acquire store read lock
+	st.mutex.RLock()
+	defer st.mutex.RUnlock()
+
+	// Pass to unprotected fn
+	return st.getStream(key)
+}
+
+func (st *KVStore) getStream(key string) (io.ReadCloser, error) {
+	// Acquire read lock for key
+	runlock := st.mutexMap.RLock(key)
+
+	// Attempt to open stream for read
+	rd, err := st.storage.ReadStream(key)
+	if err != nil {
+		runlock()
+		return nil, err
+	}
+
+	// Wrap readcloser in our own callback closer
+	return util.ReadCloserWithCallback(rd, runlock), nil
+}
+
+// Put places the bytes at the supplied key location in the store
+func (st *KVStore) Put(key string, value []byte) error {
+	// Acquire store write lock
+	st.mutex.Lock()
+	defer st.mutex.Unlock()
+
+	// Pass to unprotected fn
+	return st.put(key, value)
+}
+
+func (st *KVStore) put(key string, value []byte) error {
+	// Acquire write lock for key
+	unlock := st.mutexMap.Lock(key)
+	defer unlock()
+
+	// Write file bytes
+	return st.storage.WriteBytes(key, value)
+}
+
+// PutStream writes the bytes from the supplied Reader at the supplied key location in the store
+func (st *KVStore) PutStream(key string, r io.Reader) error {
+	// Acquire store write lock
+	st.mutex.Lock()
+	defer st.mutex.Unlock()
+
+	// Pass to unprotected fn
+	return st.putStream(key, r)
+}
+
+func (st *KVStore) putStream(key string, r io.Reader) error {
+	// Acquire write lock for key
+	unlock := st.mutexMap.Lock(key)
+	defer unlock()
+
+	// Write file stream
+	return st.storage.WriteStream(key, r)
+}
+
+// Has checks whether the supplied key exists in the store
+func (st *KVStore) Has(key string) (bool, error) {
+	// Acquire store read lock
+	st.mutex.RLock()
+	defer st.mutex.RUnlock()
+
+	// Pass to unprotected fn
+	return st.has(key)
+}
+
+func (st *KVStore) has(key string) (bool, error) {
+	// Acquire read lock for key
+	runlock := st.mutexMap.RLock(key)
+	defer runlock()
+
+	// Stat file on disk
+	return st.storage.Stat(key)
+}
+
+// Delete removes the supplied key-value pair from the store
+func (st *KVStore) Delete(key string) error {
+	// Acquire store write lock
+	st.mutex.Lock()
+	defer st.mutex.Unlock()
+
+	// Pass to unprotected fn
+	return st.delete(key)
+}
+
+func (st *KVStore) delete(key string) error {
+	// Acquire write lock for key
+	unlock := st.mutexMap.Lock(key)
+	defer unlock()
+
+	// Remove file from disk
+	return st.storage.Remove(key)
+}
+
+// Iterator returns an Iterator for key-value pairs in the store, using supplied match function
+func (st *KVStore) Iterator(matchFn func(string) bool) (*KVIterator, error) {
+	// If no function, match all
+	if matchFn == nil {
+		matchFn = func(string) bool { return true }
+	}
+
+	// Get store read lock
+	st.mutex.RLock()
+
+	// Setup the walk keys function
+	entries := []storage.StorageEntry{}
+	walkFn := func(entry storage.StorageEntry) {
+		// Ignore unmatched entries
+		if !matchFn(entry.Key()) {
+			return
+		}
+
+		// Add to entries
+		entries = append(entries, entry)
+	}
+
+	// Walk keys in the storage
+	err := st.storage.WalkKeys(&storage.WalkKeysOptions{WalkFn: walkFn})
+	if err != nil {
+		st.mutex.RUnlock()
+		return nil, err
+	}
+
+	// Return new iterator
+	return &KVIterator{
+		store:   st,
+		entries: entries,
+		index:   -1,
+		key:     "",
+		onClose: st.mutex.RUnlock,
+	}, nil
+}
+
+// Read provides a read-only window to the store, holding it in a read-locked state until
+// the supplied function returns
+func (st *KVStore) Read(do func(*StateRO)) {
+	// Get store read lock
+	st.mutex.RLock()
+	defer st.mutex.RUnlock()
+
+	// Create new store state (defer close)
+	state := &StateRO{store: st}
+	defer state.close()
+
+	// Pass state
+	do(state)
+}
+
+// Update provides a read-write window to the store, holding it in a read-write-locked state
+// until the supplied functions returns
+func (st *KVStore) Update(do func(*StateRW)) {
+	// Get store lock
+	st.mutex.Lock()
+	defer st.mutex.Unlock()
+
+	// Create new store state (defer close)
+	state := &StateRW{store: st}
+	defer state.close()
+
+	// Pass state
+	do(state)
+}