Rework the storage interface so that operations are asynchronous.

[bluesky.git] / bluesky / store.c

diff --git a/bluesky/store.c b/bluesky/store.c
index 52cc6b3..13a080f 100644 (file)
--- a/bluesky/store.c
+++ b/bluesky/store.c
@@ -14,7 +14,8 @@
 
 /* Interaction with cloud storage.  We expose very simple GET/PUT style
  * interface, which different backends can implement.  Available backends
- * (will) include Amazon S3 and a simple local store for testing purposes. */
+ * (will) include Amazon S3 and a simple local store for testing purposes.
+ * Operations may be performed asynchronously. */
 
 struct _BlueSkyStore {
     const BlueSkyStoreImplementation *impl;
@@ -53,17 +54,79 @@ void bluesky_store_free(BlueSkyStore *store)
     g_free(store);
 }
 
+BlueSkyStoreAsync *bluesky_store_async_new(BlueSkyStore *store)
+{
+    BlueSkyStoreAsync *async;
+
+    async = g_new(BlueSkyStoreAsync, 1);
+    async->store = store;
+    async->lock = g_mutex_new();
+    async->completion_cond = g_cond_new();
+    async->status = ASYNC_NEW;
+    async->op = STORE_OP_NONE;
+    async->key = NULL;
+    async->data = NULL;
+    async->result = -1;
+    async->store_private = NULL;
+
+    return async;
+}
+
+/* Block until the given operation has completed. */
+void bluesky_store_async_wait(BlueSkyStoreAsync *async)
+{
+    g_return_if_fail(async != NULL);
+    g_mutex_lock(async->lock);
+
+    if (async->status == ASYNC_NEW) {
+        g_error("bluesky_store_async_wait on a new async object!\n");
+        g_mutex_unlock(async->lock);
+        return;
+    }
+
+    while (async->status != ASYNC_COMPLETE) {
+        g_cond_wait(async->completion_cond, async->lock);
+    }
+}
+
+/* Mark an asynchronous operation as complete.  This should only be called by
+ * the store implementations.  The lock must be held when calling this
+ * function. */
+void bluesky_store_async_mark_complete(BlueSkyStoreAsync *async)
+{
+    async->status = ASYNC_COMPLETE;
+    g_cond_broadcast(async->completion_cond);
+}
+
+/* Convenience wrappers that perform a single operation synchronously. */
 BlueSkyRCStr *bluesky_store_get(BlueSkyStore *store, const gchar *key)
 {
-    return store->impl->get(store->handle, key);
+    BlueSkyStoreAsync *async = bluesky_store_async_new(store);
+    async->op = STORE_OP_GET;
+    async->key = g_strdup(key);
+    store->impl->submit(store->handle, async);
+
+    bluesky_store_async_wait(async);
+
+    BlueSkyRCStr *data = async->data;
+    bluesky_string_ref(data);
+    return data;
 }
 
 void bluesky_store_put(BlueSkyStore *store,
                        const gchar *key, BlueSkyRCStr *val)
 {
-    store->impl->put(store->handle, key, val);
+    BlueSkyStoreAsync *async = bluesky_store_async_new(store);
+    async->op = STORE_OP_PUT;
+    async->key = g_strdup(key);
+    bluesky_string_ref(val);
+    async->data = val;
+    store->impl->submit(store->handle, async);
+
+    bluesky_store_async_wait(async);
 }
 
+#if 0
 /* Simple in-memory data store for test purposes. */
 typedef struct {
     GMutex *lock;
@@ -145,10 +208,11 @@ static BlueSkyStoreImplementation filestore_impl = {
     .get = filestore_get,
     .put = filestore_put,
 };
+#endif
 
 void bluesky_store_init()
 {
     store_implementations = g_hash_table_new(g_str_hash, g_str_equal);
-    bluesky_store_register(&memstore_impl, "mem");
-    bluesky_store_register(&filestore_impl, "file");
+    //bluesky_store_register(&memstore_impl, "mem");
+    //bluesky_store_register(&filestore_impl, "file");
 }