/* 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;
g_free(store);
}
-BlueSkyRCStr *bluesky_store_get(BlueSkyStore *store, const gchar *key)
+BlueSkyStoreAsync *bluesky_store_async_new(BlueSkyStore *store)
{
- return store->impl->get(store->handle, key);
-}
+ BlueSkyStoreAsync *async;
-void bluesky_store_put(BlueSkyStore *store,
- const gchar *key, BlueSkyRCStr *val)
-{
- store->impl->put(store->handle, key, val);
-}
+ 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;
-/* Create and return a new reference-counted string. The reference count is
- * initially one. The newly-returned string takes ownership of the memory
- * pointed at by data, and will call g_free on it when the reference count
- * drops to zero. */
-BlueSkyRCStr *bluesky_string_new(gpointer data, gsize len)
-{
- BlueSkyRCStr *string = g_new(BlueSkyRCStr, 1);
- string->data = data;
- string->len = len;
- g_atomic_int_set(&string->refcount, 1);
- return string;
+ return async;
}
-void bluesky_string_ref(BlueSkyRCStr *string)
+/* Block until the given operation has completed. */
+void bluesky_store_async_wait(BlueSkyStoreAsync *async)
{
- if (string == NULL)
+ 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;
+ }
- g_atomic_int_inc(&string->refcount);
+ while (async->status != ASYNC_COMPLETE) {
+ g_cond_wait(async->completion_cond, async->lock);
+ }
}
-void bluesky_string_unref(BlueSkyRCStr *string)
+/* 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)
{
- if (string == NULL)
- return;
+ async->status = ASYNC_COMPLETE;
+ g_cond_broadcast(async->completion_cond);
+}
- if (g_atomic_int_dec_and_test(&string->refcount)) {
- g_free(string->data);
- g_free(string);
- }
+/* Convenience wrappers that perform a single operation synchronously. */
+BlueSkyRCStr *bluesky_store_get(BlueSkyStore *store, const gchar *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;
}
-/* Duplicate and return a new reference-counted string, containing a copy of
- * the original data, with a reference count of 1. As an optimization, if the
- * passed-in string already has a reference count of 1, the original is
- * returned. Can be used to make a mutable copy of a shared string. For this
- * to truly be safe, it is probably needed that there be some type of lock
- * protecting access to the string. */
-BlueSkyRCStr *bluesky_string_dup(BlueSkyRCStr *string)
+void bluesky_store_put(BlueSkyStore *store,
+ const gchar *key, BlueSkyRCStr *val)
{
- if (string == NULL)
- return NULL;
+ 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);
- if (g_atomic_int_dec_and_test(&string->refcount)) {
- /* There are no other shared copies, so return this one. */
- g_atomic_int_inc(&string->refcount);
- return string;
- } else {
- return bluesky_string_new(g_memdup(string->data, string->len),
- string->len);
- }
+ bluesky_store_async_wait(async);
}
+#if 0
/* Simple in-memory data store for test purposes. */
typedef struct {
GMutex *lock;
.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");
}