/**** Reference-counted strings. ****/
-void bluesky_mmap_unref(BlueSkyMmap *mmap)
-{
- if (mmap == NULL)
- return;
-
- if (g_atomic_int_dec_and_test(&mmap->refcount)) {
- munmap((void *)mmap->addr, mmap->len);
- g_free(mmap);
- }
-}
-
/* 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
}
/* Create a new BlueSkyRCStr from a memory-mapped buffer. */
-BlueSkyRCStr *bluesky_string_new_from_mmap(BlueSkyMmap *mmap,
+BlueSkyRCStr *bluesky_string_new_from_mmap(BlueSkyCacheFile *mmap,
int offset, gsize len)
{
+ g_assert(offset + len <= mmap->len);
+
BlueSkyRCStr *string = g_new(BlueSkyRCStr, 1);
string->mmap = mmap;
- g_atomic_int_inc(&mmap->refcount);
+ g_atomic_int_inc(&mmap->mapcount);
string->data = (char *)mmap->addr + offset;
string->len = len;
g_atomic_int_set(&string->refcount, 1);
else
return (BlueSkyInode *)head->prev->data;
}
+
+/**** Range sets. ****/
+
+/* These are a data structure which can track a set of discontiguous integer
+ * ranges--such as the partitioning of the inode number space or the bytes in a
+ * log file into objects. This current prototype implementation just tracks
+ * the starting offset with a hash table and doesn't track the length, but
+ * should be extended later to track properly. */
+
+struct BlueSkyRangeset {
+ GSequence *seq;
+};
+
+static gint compare64(gconstpointer a, gconstpointer b, gpointer user_data)
+{
+ uint64_t x = *(uint64_t *)a;
+ uint64_t y = *(uint64_t *)b;
+
+ if (x < y)
+ return -1;
+ else if (x > y)
+ return 1;
+ else
+ return 0;
+}
+
+BlueSkyRangeset *bluesky_rangeset_new()
+{
+ BlueSkyRangeset *rangeset = g_new(BlueSkyRangeset, 1);
+ rangeset->seq = g_sequence_new(g_free);
+ return rangeset;
+}
+
+void bluesky_rangeset_free(BlueSkyRangeset *rangeset)
+{
+ g_sequence_free(rangeset->seq);
+ g_free(rangeset);
+}
+
+gboolean bluesky_rangeset_insert(BlueSkyRangeset *rangeset,
+ uint64_t start, uint64_t length,
+ gpointer data)
+{
+ GSequenceIter *i;
+ i = g_sequence_search(rangeset->seq, &start, compare64, NULL);
+ i = g_sequence_iter_prev(i);
+
+ /* TODO: Checks that no other item overlaps. */
+
+ BlueSkyRangesetItem *item = g_new(BlueSkyRangesetItem, 1);
+ item->start = start;
+ item->length = length;
+ item->data = data;
+ g_sequence_insert_sorted(rangeset->seq, item, compare64, NULL);
+
+ return TRUE;
+}
+
+const BlueSkyRangesetItem *bluesky_rangeset_lookup(BlueSkyRangeset *rangeset,
+ uint64_t offset)
+{
+ GSequenceIter *i;
+ i = g_sequence_search(rangeset->seq, &offset, compare64, NULL);
+ i = g_sequence_iter_prev(i);
+ if (g_sequence_iter_is_end(i))
+ return NULL;
+
+ BlueSkyRangesetItem *item = (BlueSkyRangesetItem *)g_sequence_get(i);
+ if (offset >= item->start && offset < item->start + item->length)
+ return item;
+ else
+ return NULL;
+}
+
+/* Look up the first rangeset item starting at or following the given address.
+ * Can be used to iterate through a rangeset. */
+const BlueSkyRangesetItem *bluesky_rangeset_lookup_next(BlueSkyRangeset *rangeset, uint64_t offset)
+{
+ GSequenceIter *i;
+ i = g_sequence_search(rangeset->seq, &offset, compare64, NULL);
+ i = g_sequence_iter_prev(i);
+ if (g_sequence_iter_is_end(i))
+ return NULL;
+ BlueSkyRangesetItem *item = (BlueSkyRangesetItem *)g_sequence_get(i);
+ if (item->start < offset) {
+ i = g_sequence_iter_next(i);
+ if (g_sequence_iter_is_end(i))
+ item = NULL;
+ else
+ item = (BlueSkyRangesetItem *)g_sequence_get(i);
+ }
+ return item;
+}