X-Git-Url: https://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb2%2Fprivate.h;h=63354a43dd829c52f82d0a933783f6c67ce8782b;hp=e15d1ad835968bfe76a89ac97f64ead1e6db1b2a;hb=f6067e4cbd7b7415571f12438aec00faec5657fb;hpb=e5bb37eaf32db72f6f17eb01b8de5404fc3ce21c

diff --git a/ccan/tdb2/private.h b/ccan/tdb2/private.h
index e15d1ad8..63354a43 100644
--- a/ccan/tdb2/private.h
+++ b/ccan/tdb2/private.h
@@ -116,6 +116,9 @@ typedef int tdb_bool_err;
 #define TDB_OFF_HASH_EXTRA_BIT 57
 #define TDB_OFF_UPPER_STEAL_SUBHASH_BIT 56
 
+/* Additional features we understand.  Currently: none. */
+#define TDB_FEATURE_MASK ((uint64_t)0)
+
 /* The bit number where we store the extra hash bits. */
 /* Convenience mask to get actual offset. */
 #define TDB_OFF_MASK \
@@ -240,7 +243,12 @@ struct tdb_header {
 	tdb_off_t free_table; /* (First) free table. */
 	tdb_off_t recovery; /* Transaction recovery area. */
 
-	tdb_off_t reserved[26];
+	uint64_t features_used; /* Features all writers understand */
+	uint64_t features_offered; /* Features offered */
+
+	uint64_t seqnum; /* Sequence number for TDB_SEQNUM */
+
+	tdb_off_t reserved[23];
 
 	/* Top level hash table. */
 	tdb_off_t hashtable[1ULL << TDB_TOPLEVEL_HASH_BITS];
@@ -294,7 +302,8 @@ enum tdb_lock_flags {
 	TDB_LOCK_NOCHECK = 4,
 };
 
-struct tdb_lock_type {
+struct tdb_lock {
+	struct tdb_context *owner;
 	uint32_t off;
 	uint32_t count;
 	uint32_t ltype;
@@ -309,21 +318,38 @@ struct tdb_access_hdr {
 	bool convert;
 };
 
-struct tdb_context {
-	/* Filename of the database. */
-	const char *name;
+struct tdb_file {
+	/* Single list of all TDBs, to detect multiple opens. */
+	struct tdb_file *next;
+
+	/* How many are sharing us? */
+	unsigned int refcnt;
 
 	/* Mmap (if any), or malloc (for TDB_INTERNAL). */
 	void *map_ptr;
 
-	/* Are we accessing directly? (debugging check). */
-	int direct_access;
+	/* How much space has been mapped (<= current file size) */
+	tdb_len_t map_size;
 
-	 /* Open file descriptor (undefined for TDB_INTERNAL). */
+	/* The file descriptor (-1 for TDB_INTERNAL). */
 	int fd;
 
-	/* How much space has been mapped (<= current file size) */
-	tdb_len_t map_size;
+	/* Lock information */
+	struct tdb_lock allrecord_lock;
+	size_t num_lockrecs;
+	struct tdb_lock *lockrecs;
+
+	/* Identity of this file. */
+	dev_t device;
+	ino_t inode;
+};
+
+struct tdb_context {
+	/* Filename of the database. */
+	const char *name;
+
+	/* Are we accessing directly? (debugging check). */
+	int direct_access;
 
 	/* Operating read-only? (Opened O_RDONLY, or in traverse_read) */
 	bool read_only;
@@ -359,20 +385,16 @@ struct tdb_context {
 	/* IO methods: changes for transactions. */
 	const struct tdb_methods *methods;
 
-	/* Lock information */
-	struct tdb_lock_type allrecord_lock;
-	size_t num_lockrecs;
-	struct tdb_lock_type *lockrecs;
-
 	struct tdb_attribute_stats *stats;
 
 	/* Direct access information */
 	struct tdb_access_hdr *access;
 
-	/* Single list of all TDBs, to avoid multiple opens. */
-	struct tdb_context *next;
-	dev_t device;
-	ino_t inode;
+	/* Last error we returned. */
+	enum TDB_ERROR last_error;
+
+	/* The actual file information */
+	struct tdb_file *file;
 };
 
 struct tdb_methods {
@@ -461,7 +483,7 @@ void tdb_io_init(struct tdb_context *tdb);
 void *tdb_convert(const struct tdb_context *tdb, void *buf, tdb_len_t size);
 
 /* Unmap and try to map the tdb. */
-void tdb_munmap(struct tdb_context *tdb);
+void tdb_munmap(struct tdb_file *file);
 void tdb_mmap(struct tdb_context *tdb);
 
 /* Either alloc a copy, or give direct access.  Release frees or noop. */
@@ -506,6 +528,9 @@ enum TDB_ERROR tdb_write_convert(struct tdb_context *tdb, tdb_off_t off,
 enum TDB_ERROR tdb_read_convert(struct tdb_context *tdb, tdb_off_t off,
 				void *rec, size_t len);
 
+/* Bump the seqnum (caller checks for tdb->flags & TDB_SEQNUM) */
+void tdb_inc_seqnum(struct tdb_context *tdb);
+
 /* Adds a stat, if it's in range. */
 void add_stat_(struct tdb_context *tdb, uint64_t *stat, size_t val);
 #define add_stat(tdb, statname, val)					\
@@ -515,8 +540,6 @@ void add_stat_(struct tdb_context *tdb, uint64_t *stat, size_t val);
 	} while (0)
 
 /* lock.c: */
-void tdb_lock_init(struct tdb_context *tdb);
-
 /* Lock/unlock a range of hashes. */
 enum TDB_ERROR tdb_lock_hashes(struct tdb_context *tdb,
 			       tdb_off_t hash_lock, tdb_len_t hash_range,
@@ -525,6 +548,9 @@ enum TDB_ERROR tdb_unlock_hashes(struct tdb_context *tdb,
 				 tdb_off_t hash_lock,
 				 tdb_len_t hash_range, int ltype);
 
+/* For closing the file. */
+void tdb_unlock_all(struct tdb_context *tdb);
+
 /* Lock/unlock a particular free bucket. */
 enum TDB_ERROR tdb_lock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off,
 				    enum tdb_lock_flags waitflag);