X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=bluesky%2Fcloudlog.c;h=9d2fe373dcbe1f75116d692e696f4904dee63b4b;hb=2f883084c4393dc7b730df2e778b9f2fc14f70e0;hp=40067fd3661f91d4ec9e45a9019a73d9043c8bd6;hpb=a82b60b3b683840a7074110831bcbaa16a40f0eb;p=bluesky.git

diff --git a/bluesky/cloudlog.c b/bluesky/cloudlog.c
index 40067fd..9d2fe37 100644
--- a/bluesky/cloudlog.c
+++ b/bluesky/cloudlog.c
@@ -78,7 +78,7 @@ guint bluesky_cloudlog_hash(gconstpointer a)
  * before writing a batch to the cloud, handling indirection through items like
  * the inode map, etc. */
 
-BlueSkyCloudLog *bluesky_cloudlog_new(BlueSkyFS *fs)
+BlueSkyCloudLog *bluesky_cloudlog_new(BlueSkyFS *fs, const BlueSkyCloudID *id)
 {
     BlueSkyCloudLog *log = g_new0(BlueSkyCloudLog, 1);
 
@@ -86,7 +86,10 @@ BlueSkyCloudLog *bluesky_cloudlog_new(BlueSkyFS *fs)
     log->cond = g_cond_new();
     log->fs = fs;
     log->type = LOGTYPE_UNKNOWN;
-    log->id = bluesky_cloudlog_new_id();
+    if (id != NULL)
+        memcpy(&log->id, id, sizeof(BlueSkyCloudID));
+    else
+        log->id = bluesky_cloudlog_new_id();
     log->links = g_array_new(FALSE, TRUE, sizeof(BlueSkyCloudLog *));
     g_atomic_int_set(&log->refcount, 1);
 
@@ -177,22 +180,29 @@ void bluesky_cloudlog_insert(BlueSkyCloudLog *log)
     g_mutex_unlock(log->fs->lock);
 }
 
-struct log_header {
-    char magic[4];
-    uint32_t size;
-    BlueSkyCloudID id;
-    uint32_t pointer_count;
-} __attribute__((packed));
+/* Look up the cloud log entry for the given ID.  If create is TRUE and the
+ * item does not exist, create a special pending entry that can later be filled
+ * in when the real item is loaded.  The returned item has a reference held.
+ * As a special case, if a null ID is provided then NULL is returned. */
+BlueSkyCloudLog *bluesky_cloudlog_get(BlueSkyFS *fs, BlueSkyCloudID id)
+{
+    static BlueSkyCloudID id0 = {{0}};
 
-struct logref {
-    BlueSkyCloudID id;
-    BlueSkyCloudPointer location;
-} __attribute__((packed));
+    if (memcmp(&id, &id0, sizeof(BlueSkyCloudID)) == 0)
+        return NULL;
 
-struct log_footer {
-    char refmagic[4];
-    struct logref refs[0];
-};
+    g_mutex_lock(fs->lock);
+    BlueSkyCloudLog *item;
+    item = g_hash_table_lookup(fs->locations, &id);
+    if (item == NULL) {
+        item = bluesky_cloudlog_new(fs, &id);
+        g_hash_table_insert(fs->locations, &id, item);
+    } else {
+        bluesky_cloudlog_ref(item);
+    }
+    g_mutex_unlock(fs->lock);
+    return item;
+}
 
 /* Ensure that a cloud log item is loaded in memory, and if not read it in.
  * TODO: Make asynchronous, and make this also fetch from the cloud.  Right now
@@ -202,20 +212,52 @@ void bluesky_cloudlog_fetch(BlueSkyCloudLog *log)
     if (log->data != NULL)
         return;
 
+    /* There are actually two cases: a full deserialization if we have not ever
+     * read the object before, and a partial deserialization where the metadata
+     * is already in memory and we just need to remap the data.  If the object
+     * type has not yet been set, we'll need to read and parse the metadata.
+     * Once that is done, we can fall through the case of remapping the data
+     * itself. */
+    if (log->type == LOGTYPE_UNKNOWN) {
+        BlueSkyRCStr *raw = NULL;
+        if ((log->location_flags | log->pending_write) & CLOUDLOG_JOURNAL) {
+            raw = bluesky_log_map_object(log->fs, -1, log->log_seq,
+                                         log->log_offset, log->log_size);
+        }
+
+        if (raw == NULL && (log->location_flags & CLOUDLOG_CLOUD)) {
+            log->location_flags &= ~CLOUDLOG_JOURNAL;
+            raw = bluesky_log_map_object(log->fs,
+                                         log->location.directory,
+                                         log->location.sequence,
+                                         log->location.offset,
+                                         log->location.size);
+        }
+
+        g_assert(raw != NULL);
+        bluesky_deserialize_cloudlog(log, raw->data, raw->len);
+        bluesky_string_unref(raw);
+    }
+
+    /* At this point all metadata should be available and we need only remap
+     * the object data. */
+
+    int offset;
     if ((log->location_flags | log->pending_write) & CLOUDLOG_JOURNAL) {
         bluesky_cloudlog_stats_update(log, -1);
+        offset = log->log_offset + sizeof(struct log_header);
         log->data = bluesky_log_map_object(log->fs, -1, log->log_seq,
-                                           log->log_offset, log->log_size);
+                                           offset, log->data_size);
         bluesky_cloudlog_stats_update(log, 1);
     }
 
     if (log->data == NULL && (log->location_flags & CLOUDLOG_CLOUD)) {
         log->location_flags &= ~CLOUDLOG_JOURNAL;
         bluesky_cloudlog_stats_update(log, -1);
+        offset = log->location.offset + sizeof(struct cloudlog_header);
         log->data = bluesky_log_map_object(log->fs, log->location.directory,
                                            log->location.sequence,
-                                           log->location.offset,
-                                           log->location.size);
+                                           offset, log->data_size);
         bluesky_cloudlog_stats_update(log, 1);
     }
 
@@ -248,22 +290,32 @@ BlueSkyCloudPointer bluesky_cloudlog_serialize(BlueSkyCloudLog *log,
 
     bluesky_cloudlog_stats_update(log, -1);
 
+    GString *data1 = g_string_new("");
+    GString *data2 = g_string_new("");
+    GString *data3 = g_string_new("");
+    bluesky_serialize_cloudlog(log, data1, data2, data3);
+
     /* TODO: Right now offset/size are set to the raw data, but we should add
      * header parsing to the code which loads objects back in. */
     log->location = state->location;
-    log->location.offset = state->data->len + sizeof(struct log_header);
-    log->location.size = log->data->len;
-        /* = sizeof(struct log_header) + sizeof(BlueSkyCloudID) * 0
-           + log->data->len; */
-
-    struct log_header header;
-    memcpy(header.magic, "AgI ", 4);
-    header.size = GUINT32_TO_LE(log->location.size);
+    log->location.offset = state->data->len;
+    log->data_size = data1->len;
+
+    struct cloudlog_header header;
+    memcpy(header.magic, CLOUDLOG_MAGIC, 4);
+    header.type = log->type + '0';
+    header.size1 = GUINT32_TO_LE(data1->len);
+    header.size2 = GUINT32_TO_LE(data2->len);
+    header.size3 = GUINT32_TO_LE(data3->len);
     header.id = log->id;
-    header.pointer_count = GUINT32_TO_LE(0);
+    header.inum = GUINT64_TO_LE(log->inum);
 
     g_string_append_len(state->data, (const char *)&header, sizeof(header));
-    g_string_append_len(state->data, log->data->data, log->data->len);
+    g_string_append_len(state->data, data1->str, data1->len);
+    g_string_append_len(state->data, data2->str, data2->len);
+    g_string_append_len(state->data, data3->str, data3->len);
+
+    log->location.size = state->data->len - log->location.offset;
 
     /* If the object we flushed was an inode, update the inode map. */
     if (log->type == LOGTYPE_INODE) {
@@ -272,6 +324,8 @@ BlueSkyCloudPointer bluesky_cloudlog_serialize(BlueSkyCloudLog *log,
                                                         log->inum, 1);
         entry->id = log->id;
         entry->location = log->location;
+        entry->item = log;
+        bluesky_cloudlog_ref(entry->item);
         g_mutex_unlock(fs->lock);
     }