* TODO: Licensing
*/
+#include <stdio.h>
#include <stdint.h>
+#include <inttypes.h>
#include <glib.h>
#include <string.h>
-#include "bluesky.h"
+#include "bluesky-private.h"
/* Core filesystem. Different proxies, such as the NFSv3 one, interface to
* this, but the core actually tracks the data which is stored. So far we just
/* Update an inode to indicate that a modification was made. This increases
* the change counter, updates the ctime to the current time, and optionally
- * updates the mtime. */
+ * updates the mtime. inode must already be locked. */
void bluesky_inode_update_ctime(BlueSkyInode *inode, gboolean update_mtime)
{
int64_t now = bluesky_get_current_time();
inode->mtime = now;
}
-/* Compute the HMAC keyed-hash function using the given hash algorithm, data,
- * and key. */
-void compute_hmac(GChecksumType algo,
- const guchar *data, gsize data_len,
- const guchar *key, gsize key_len,
- guint8 *buffer, gsize *digest_len)
-{
- int block_size;
-
- switch (algo) {
- case G_CHECKSUM_MD5:
- case G_CHECKSUM_SHA1:
- case G_CHECKSUM_SHA256:
- block_size = 64;
- break;
- default:
- g_error("Unknown hash algorithm for HMAC: %d\n", algo);
- }
-
- gsize digest_size = g_checksum_type_get_length(algo);
-
- guchar keybuf[block_size];
- memset(keybuf, 0, block_size);
- memcpy(keybuf, key, MIN(block_size, key_len));
- for (int i = 0; i < block_size; i++)
- keybuf[i] ^= 0x36;
-
- GChecksum *csum1 = g_checksum_new(algo);
- g_checksum_update(csum1, keybuf, block_size);
- g_checksum_update(csum1, data, data_len);
- guint8 digest[digest_size];
- g_checksum_get_digest(csum1, digest, &digest_size);
-
- memset(keybuf, 0, block_size);
- memcpy(keybuf, key, MIN(block_size, key_len));
- for (int i = 0; i < block_size; i++)
- keybuf[i] ^= 0x5c;
-
- GChecksum *csum2 = g_checksum_new(algo);
- g_checksum_update(csum2, keybuf, block_size);
- g_checksum_update(csum2, digest, digest_size);
-
- g_checksum_get_digest(csum2, buffer, digest_len);
-
- g_checksum_free(csum1);
- g_checksum_free(csum2);
-}
-
/* Unfortunately a glib hash table is only guaranteed to be able to store
* 32-bit keys if we use the key directly. If we want 64-bit inode numbers,
* we'll have to allocate memory to store the 64-bit inumber, and use a pointer
return fs;
}
+BlueSkyFS *bluesky_init_fs(gchar *name, BlueSkyStore *store)
+{
+ BlueSkyRCStr *data = bluesky_store_get(store, "superblock");
+ if (data != NULL) {
+ BlueSkyFS *fs = bluesky_deserialize_superblock(data->data);
+ if (fs != NULL) {
+ fs->store = store;
+ g_print("Loaded filesystem superblock\n");
+ g_free(fs->name);
+ fs->name = g_strdup(name);
+ return fs;
+ }
+ }
+
+ g_print("Initializing fresh filesystem\n");
+ BlueSkyFS *fs = bluesky_new_fs(name);
+ fs->store = store;
+
+ BlueSkyInode *root = bluesky_new_inode(BLUESKY_ROOT_INUM, fs,
+ BLUESKY_DIRECTORY);
+ root->nlink = 1;
+ root->mode = 0755;
+ bluesky_insert_inode(fs, root);
+
+ bluesky_inode_flush(fs, root);
+ bluesky_superblock_flush(fs);
+
+ return fs;
+}
+
/* Inode reference counting. */
void bluesky_inode_ref(BlueSkyInode *inode)
{
void bluesky_inode_unref(BlueSkyInode *inode)
{
if (g_atomic_int_dec_and_test(&inode->refcount)) {
- g_error("Reference count for inode %lld dropped to zero!\n",
+ g_error("Reference count for inode %"PRIu64" dropped to zero!\n",
inode->inum);
}
}
/* Allocate a fresh inode number which has not been used before within a
- * filesystem. */
+ * filesystem. fs must already be locked. */
uint64_t bluesky_fs_alloc_inode(BlueSkyFS *fs)
{
uint64_t inum;
- g_mutex_lock(fs->lock);
inum = fs->next_inum;
fs->next_inum++;
- g_mutex_unlock(fs->lock);
+
+ bluesky_superblock_flush(fs);
return inum;
}
case BLUESKY_DIRECTORY:
i->dirents = g_sequence_new(bluesky_dirent_destroy);
i->dirhash = g_hash_table_new(g_str_hash, g_str_equal);
+ i->dirhash_folded = g_hash_table_new(g_str_hash, g_str_equal);
break;
case BLUESKY_BLOCK:
case BLUESKY_CHARACTER:
/* Retrieve an inode from the filesystem. Eventually this will be a cache and
* so we might need to go fetch the inode from elsewhere; for now all
- * filesystem state is stored here. */
+ * filesystem state is stored here. inode is returned locked with a reference
+ * held. */
BlueSkyInode *bluesky_get_inode(BlueSkyFS *fs, uint64_t inum)
{
BlueSkyInode *inode = NULL;
+ if (inum == 0) {
+ return NULL;
+ }
+
g_mutex_lock(fs->lock);
inode = (BlueSkyInode *)g_hash_table_lookup(fs->inodes, &inum);
+
+ if (inode == NULL) {
+ bluesky_inode_fetch(fs, inum);
+ inode = (BlueSkyInode *)g_hash_table_lookup(fs->inodes, &inum);
+ }
+
+ if (inode != NULL) {
+ bluesky_inode_ref(inode);
+ }
+
g_mutex_unlock(fs->lock);
return inode;
}
-/* Insert an inode into the filesystem inode cache. */
+/* Insert an inode into the filesystem inode cache. fs should be locked. */
void bluesky_insert_inode(BlueSkyFS *fs, BlueSkyInode *inode)
{
- g_mutex_lock(fs->lock);
g_hash_table_insert(fs->inodes, &inode->inum, inode);
- g_mutex_unlock(fs->lock);
+}
+
+/* Synchronize an inode to stable storage. */
+void bluesky_inode_flush(BlueSkyFS *fs, BlueSkyInode *inode)
+{
+ GString *buf = g_string_new("");
+ bluesky_serialize_inode(buf, inode);
+ BlueSkyRCStr *data = bluesky_string_new_from_gstring(buf);
+
+ char key[64];
+ sprintf(key, "inode-%016"PRIx64, inode->inum);
+
+ bluesky_store_put(fs->store, key, data);
+}
+
+/* Fetch an inode from stable storage. */
+void bluesky_inode_fetch(BlueSkyFS *fs, uint64_t inum)
+{
+ char key[64];
+ sprintf(key, "inode-%016"PRIx64, inum);
+ BlueSkyRCStr *data = bluesky_store_get(fs->store, key);
+ if (data == NULL)
+ return;
+
+ BlueSkyInode *inode = bluesky_deserialize_inode(fs, data->data);
+ if (inode != NULL) {
+ bluesky_insert_inode(fs, inode);
+ }
+}
+
+/* Synchronize filesystem superblock to stable storage. */
+void bluesky_superblock_flush(BlueSkyFS *fs)
+{
+ GString *buf = g_string_new("");
+ bluesky_serialize_superblock(buf, fs);
+ BlueSkyRCStr *data = bluesky_string_new_from_gstring(buf);
+
+ g_print("Syncing superblock...\n");
+
+ bluesky_store_put(fs->store, "superblock", data);
}