Merge 2610c05b5b95cc7036b3d6dfb894c6cfbdb68483 as Samba-4.0alpha16

1 files changed, 486 insertions, 0 deletions

diff --git a/lib/tdb2/tdb.c b/lib/tdb2/tdb.c
new file mode 100644
index 0000000000..753ccb0c8b
--- /dev/null
+++ b/lib/tdb2/tdb.c
@@ -0,0 +1,486 @@
+#include "private.h"
+#ifndef _SAMBA_BUILD_
+#include <ccan/asprintf/asprintf.h>
+#include <stdarg.h>
+#endif
+
+static enum TDB_ERROR update_rec_hdr(struct tdb_context *tdb,
+				     tdb_off_t off,
+				     tdb_len_t keylen,
+				     tdb_len_t datalen,
+				     struct tdb_used_record *rec,
+				     uint64_t h)
+{
+	uint64_t dataroom = rec_data_length(rec) + rec_extra_padding(rec);
+	enum TDB_ERROR ecode;
+
+	ecode = set_header(tdb, rec, TDB_USED_MAGIC, keylen, datalen,
+			   keylen + dataroom, h);
+	if (ecode == TDB_SUCCESS) {
+		ecode = tdb_write_convert(tdb, off, rec, sizeof(*rec));
+	}
+	return ecode;
+}
+
+static enum TDB_ERROR replace_data(struct tdb_context *tdb,
+				   struct hash_info *h,
+				   struct tdb_data key, struct tdb_data dbuf,
+				   tdb_off_t old_off, tdb_len_t old_room,
+				   bool growing)
+{
+	tdb_off_t new_off;
+	enum TDB_ERROR ecode;
+
+	/* Allocate a new record. */
+	new_off = alloc(tdb, key.dsize, dbuf.dsize, h->h, TDB_USED_MAGIC,
+			growing);
+	if (TDB_OFF_IS_ERR(new_off)) {
+		return new_off;
+	}
+
+	/* We didn't like the existing one: remove it. */
+	if (old_off) {
+		tdb->stats.frees++;
+		ecode = add_free_record(tdb, old_off,
+					sizeof(struct tdb_used_record)
+					+ key.dsize + old_room,
+					TDB_LOCK_WAIT, true);
+		if (ecode == TDB_SUCCESS)
+			ecode = replace_in_hash(tdb, h, new_off);
+	} else {
+		ecode = add_to_hash(tdb, h, new_off);
+	}
+	if (ecode != TDB_SUCCESS) {
+		return ecode;
+	}
+
+	new_off += sizeof(struct tdb_used_record);
+	ecode = tdb->methods->twrite(tdb, new_off, key.dptr, key.dsize);
+	if (ecode != TDB_SUCCESS) {
+		return ecode;
+	}
+
+	new_off += key.dsize;
+	ecode = tdb->methods->twrite(tdb, new_off, dbuf.dptr, dbuf.dsize);
+	if (ecode != TDB_SUCCESS) {
+		return ecode;
+	}
+
+	if (tdb->flags & TDB_SEQNUM)
+		tdb_inc_seqnum(tdb);
+
+	return TDB_SUCCESS;
+}
+
+static enum TDB_ERROR update_data(struct tdb_context *tdb,
+				  tdb_off_t off,
+				  struct tdb_data dbuf,
+				  tdb_len_t extra)
+{
+	enum TDB_ERROR ecode;
+
+	ecode = tdb->methods->twrite(tdb, off, dbuf.dptr, dbuf.dsize);
+	if (ecode == TDB_SUCCESS && extra) {
+		/* Put a zero in; future versions may append other data. */
+		ecode = tdb->methods->twrite(tdb, off + dbuf.dsize, "", 1);
+	}
+	if (tdb->flags & TDB_SEQNUM)
+		tdb_inc_seqnum(tdb);
+
+	return ecode;
+}
+
+enum TDB_ERROR tdb_store(struct tdb_context *tdb,
+			 struct tdb_data key, struct tdb_data dbuf, int flag)
+{
+	struct hash_info h;
+	tdb_off_t off;
+	tdb_len_t old_room = 0;
+	struct tdb_used_record rec;
+	enum TDB_ERROR ecode;
+
+	off = find_and_lock(tdb, key, F_WRLCK, &h, &rec, NULL);
+	if (TDB_OFF_IS_ERR(off)) {
+		return tdb->last_error = off;
+	}
+
+	/* Now we have lock on this hash bucket. */
+	if (flag == TDB_INSERT) {
+		if (off) {
+			ecode = TDB_ERR_EXISTS;
+			goto out;
+		}
+	} else {
+		if (off) {
+			old_room = rec_data_length(&rec)
+				+ rec_extra_padding(&rec);
+			if (old_room >= dbuf.dsize) {
+				/* Can modify in-place.  Easy! */
+				ecode = update_rec_hdr(tdb, off,
+						       key.dsize, dbuf.dsize,
+						       &rec, h.h);
+				if (ecode != TDB_SUCCESS) {
+					goto out;
+				}
+				ecode = update_data(tdb,
+						    off + sizeof(rec)
+						    + key.dsize, dbuf,
+						    old_room - dbuf.dsize);
+				if (ecode != TDB_SUCCESS) {
+					goto out;
+				}
+				tdb_unlock_hashes(tdb, h.hlock_start,
+						  h.hlock_range, F_WRLCK);
+				return tdb->last_error = TDB_SUCCESS;
+			}
+		} else {
+			if (flag == TDB_MODIFY) {
+				/* if the record doesn't exist and we
+				   are in TDB_MODIFY mode then we should fail
+				   the store */
+				ecode = TDB_ERR_NOEXIST;
+				goto out;
+			}
+		}
+	}
+
+	/* If we didn't use the old record, this implies we're growing. */
+	ecode = replace_data(tdb, &h, key, dbuf, off, old_room, off);
+out:
+	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
+	return tdb->last_error = ecode;
+}
+
+enum TDB_ERROR tdb_append(struct tdb_context *tdb,
+			  struct tdb_data key, struct tdb_data dbuf)
+{
+	struct hash_info h;
+	tdb_off_t off;
+	struct tdb_used_record rec;
+	tdb_len_t old_room = 0, old_dlen;
+	unsigned char *newdata;
+	struct tdb_data new_dbuf;
+	enum TDB_ERROR ecode;
+
+	off = find_and_lock(tdb, key, F_WRLCK, &h, &rec, NULL);
+	if (TDB_OFF_IS_ERR(off)) {
+		return tdb->last_error = off;
+	}
+
+	if (off) {
+		old_dlen = rec_data_length(&rec);
+		old_room = old_dlen + rec_extra_padding(&rec);
+
+		/* Fast path: can append in place. */
+		if (rec_extra_padding(&rec) >= dbuf.dsize) {
+			ecode = update_rec_hdr(tdb, off, key.dsize,
+					       old_dlen + dbuf.dsize, &rec,
+					       h.h);
+			if (ecode != TDB_SUCCESS) {
+				goto out;
+			}
+
+			off += sizeof(rec) + key.dsize + old_dlen;
+			ecode = update_data(tdb, off, dbuf,
+					    rec_extra_padding(&rec));
+			goto out;
+		}
+
+		/* Slow path. */
+		newdata = malloc(key.dsize + old_dlen + dbuf.dsize);
+		if (!newdata) {
+			ecode = tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
+					   "tdb_append:"
+					   " failed to allocate %zu bytes",
+					   (size_t)(key.dsize + old_dlen
+						    + dbuf.dsize));
+			goto out;
+		}
+		ecode = tdb->methods->tread(tdb, off + sizeof(rec) + key.dsize,
+					    newdata, old_dlen);
+		if (ecode != TDB_SUCCESS) {
+			goto out_free_newdata;
+		}
+		memcpy(newdata + old_dlen, dbuf.dptr, dbuf.dsize);
+		new_dbuf.dptr = newdata;
+		new_dbuf.dsize = old_dlen + dbuf.dsize;
+	} else {
+		newdata = NULL;
+		new_dbuf = dbuf;
+	}
+
+	/* If they're using tdb_append(), it implies they're growing record. */
+	ecode = replace_data(tdb, &h, key, new_dbuf, off, old_room, true);
+
+out_free_newdata:
+	free(newdata);
+out:
+	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
+	return tdb->last_error = ecode;
+}
+
+enum TDB_ERROR tdb_fetch(struct tdb_context *tdb, struct tdb_data key,
+			 struct tdb_data *data)
+{
+	tdb_off_t off;
+	struct tdb_used_record rec;
+	struct hash_info h;
+	enum TDB_ERROR ecode;
+
+	off = find_and_lock(tdb, key, F_RDLCK, &h, &rec, NULL);
+	if (TDB_OFF_IS_ERR(off)) {
+		return tdb->last_error = off;
+	}
+
+	if (!off) {
+		ecode = TDB_ERR_NOEXIST;
+	} else {
+		data->dsize = rec_data_length(&rec);
+		data->dptr = tdb_alloc_read(tdb, off + sizeof(rec) + key.dsize,
+					    data->dsize);
+		if (TDB_PTR_IS_ERR(data->dptr)) {
+			ecode = TDB_PTR_ERR(data->dptr);
+		} else
+			ecode = TDB_SUCCESS;
+	}
+
+	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
+	return tdb->last_error = ecode;
+}
+
+bool tdb_exists(struct tdb_context *tdb, TDB_DATA key)
+{
+	tdb_off_t off;
+	struct tdb_used_record rec;
+	struct hash_info h;
+
+	off = find_and_lock(tdb, key, F_RDLCK, &h, &rec, NULL);
+	if (TDB_OFF_IS_ERR(off)) {
+		tdb->last_error = off;
+		return false;
+	}
+	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
+
+	tdb->last_error = TDB_SUCCESS;
+	return off ? true : false;
+}
+
+enum TDB_ERROR tdb_delete(struct tdb_context *tdb, struct tdb_data key)
+{
+	tdb_off_t off;
+	struct tdb_used_record rec;
+	struct hash_info h;
+	enum TDB_ERROR ecode;
+
+	off = find_and_lock(tdb, key, F_WRLCK, &h, &rec, NULL);
+	if (TDB_OFF_IS_ERR(off)) {
+		return tdb->last_error = off;
+	}
+
+	if (!off) {
+		ecode = TDB_ERR_NOEXIST;
+		goto unlock;
+	}
+
+	ecode = delete_from_hash(tdb, &h);
+	if (ecode != TDB_SUCCESS) {
+		goto unlock;
+	}
+
+	/* Free the deleted entry. */
+	tdb->stats.frees++;
+	ecode = add_free_record(tdb, off,
+				sizeof(struct tdb_used_record)
+				+ rec_key_length(&rec)
+				+ rec_data_length(&rec)
+				+ rec_extra_padding(&rec),
+				TDB_LOCK_WAIT, true);
+
+	if (tdb->flags & TDB_SEQNUM)
+		tdb_inc_seqnum(tdb);
+
+unlock:
+	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
+	return tdb->last_error = ecode;
+}
+
+unsigned int tdb_get_flags(struct tdb_context *tdb)
+{
+	return tdb->flags;
+}
+
+void tdb_add_flag(struct tdb_context *tdb, unsigned flag)
+{
+	if (tdb->flags & TDB_INTERNAL) {
+		tdb->last_error = tdb_logerr(tdb, TDB_ERR_EINVAL,
+					     TDB_LOG_USE_ERROR,
+					     "tdb_add_flag: internal db");
+		return;
+	}
+	switch (flag) {
+	case TDB_NOLOCK:
+		tdb->flags |= TDB_NOLOCK;
+		break;
+	case TDB_NOMMAP:
+		tdb->flags |= TDB_NOMMAP;
+		tdb_munmap(tdb->file);
+		break;
+	case TDB_NOSYNC:
+		tdb->flags |= TDB_NOSYNC;
+		break;
+	case TDB_SEQNUM:
+		tdb->flags |= TDB_SEQNUM;
+		break;
+	case TDB_ALLOW_NESTING:
+		tdb->flags |= TDB_ALLOW_NESTING;
+		break;
+	default:
+		tdb->last_error = tdb_logerr(tdb, TDB_ERR_EINVAL,
+					     TDB_LOG_USE_ERROR,
+					     "tdb_add_flag: Unknown flag %u",
+					     flag);
+	}
+}
+
+void tdb_remove_flag(struct tdb_context *tdb, unsigned flag)
+{
+	if (tdb->flags & TDB_INTERNAL) {
+		tdb->last_error = tdb_logerr(tdb, TDB_ERR_EINVAL,
+					     TDB_LOG_USE_ERROR,
+					     "tdb_remove_flag: internal db");
+		return;
+	}
+	switch (flag) {
+	case TDB_NOLOCK:
+		tdb->flags &= ~TDB_NOLOCK;
+		break;
+	case TDB_NOMMAP:
+		tdb->flags &= ~TDB_NOMMAP;
+		tdb_mmap(tdb);
+		break;
+	case TDB_NOSYNC:
+		tdb->flags &= ~TDB_NOSYNC;
+		break;
+	case TDB_SEQNUM:
+		tdb->flags &= ~TDB_SEQNUM;
+		break;
+	case TDB_ALLOW_NESTING:
+		tdb->flags &= ~TDB_ALLOW_NESTING;
+		break;
+	default:
+		tdb->last_error = tdb_logerr(tdb, TDB_ERR_EINVAL,
+					     TDB_LOG_USE_ERROR,
+					     "tdb_remove_flag: Unknown flag %u",
+					     flag);
+	}
+}
+
+const char *tdb_errorstr(enum TDB_ERROR ecode)
+{
+	/* Gcc warns if you miss a case in the switch, so use that. */
+	switch (ecode) {
+	case TDB_SUCCESS: return "Success";
+	case TDB_ERR_CORRUPT: return "Corrupt database";
+	case TDB_ERR_IO: return "IO Error";
+	case TDB_ERR_LOCK: return "Locking error";
+	case TDB_ERR_OOM: return "Out of memory";
+	case TDB_ERR_EXISTS: return "Record exists";
+	case TDB_ERR_EINVAL: return "Invalid parameter";
+	case TDB_ERR_NOEXIST: return "Record does not exist";
+	case TDB_ERR_RDONLY: return "write not permitted";
+	}
+	return "Invalid error code";
+}
+
+enum TDB_ERROR tdb_error(struct tdb_context *tdb)
+{
+	return tdb->last_error;
+}
+
+enum TDB_ERROR COLD tdb_logerr(struct tdb_context *tdb,
+			       enum TDB_ERROR ecode,
+			       enum tdb_log_level level,
+			       const char *fmt, ...)
+{
+	char *message;
+	va_list ap;
+	size_t len;
+	/* tdb_open paths care about errno, so save it. */
+	int saved_errno = errno;
+
+	if (!tdb->log_fn)
+		return ecode;
+
+	va_start(ap, fmt);
+	len = vasprintf(&message, fmt, ap);
+	va_end(ap);
+
+	if (len < 0) {
+		tdb->log_fn(tdb, TDB_LOG_ERROR,
+			    "out of memory formatting message:", tdb->log_data);
+		tdb->log_fn(tdb, level, fmt, tdb->log_data);
+	} else {
+		tdb->log_fn(tdb, level, message, tdb->log_data);
+		free(message);
+	}
+	errno = saved_errno;
+	return ecode;
+}
+
+enum TDB_ERROR tdb_parse_record_(struct tdb_context *tdb,
+				 TDB_DATA key,
+				 enum TDB_ERROR (*parse)(TDB_DATA k,
+							 TDB_DATA d,
+							 void *data),
+				 void *data)
+{
+	tdb_off_t off;
+	struct tdb_used_record rec;
+	struct hash_info h;
+	enum TDB_ERROR ecode;
+
+	off = find_and_lock(tdb, key, F_RDLCK, &h, &rec, NULL);
+	if (TDB_OFF_IS_ERR(off)) {
+		return tdb->last_error = off;
+	}
+
+	if (!off) {
+		ecode = TDB_ERR_NOEXIST;
+	} else {
+		const void *dptr;
+		dptr = tdb_access_read(tdb, off + sizeof(rec) + key.dsize,
+				       rec_data_length(&rec), false);
+		if (TDB_PTR_IS_ERR(dptr)) {
+			ecode = TDB_PTR_ERR(dptr);
+		} else {
+			TDB_DATA d = tdb_mkdata(dptr, rec_data_length(&rec));
+
+			ecode = parse(key, d, data);
+			tdb_access_release(tdb, dptr);
+		}
+	}
+
+	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_RDLCK);
+	return tdb->last_error = ecode;
+}
+
+const char *tdb_name(const struct tdb_context *tdb)
+{
+	return tdb->name;
+}
+
+int64_t tdb_get_seqnum(struct tdb_context *tdb)
+{
+	tdb_off_t off = tdb_read_off(tdb, offsetof(struct tdb_header, seqnum));
+	if (TDB_OFF_IS_ERR(off))
+		tdb->last_error = off;
+	else
+		tdb->last_error = TDB_SUCCESS;
+	return off;
+}
+
+
+int tdb_fd(const struct tdb_context *tdb)
+{
+	return tdb->file->fd;
+}