X-Git-Url: https://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb2%2Ftdb.c;h=2315c485eea31be3c40af274243f39cc55f633e0;hp=1aa3baa46c24471033af359dba192ab82e3747a3;hb=751a8a34d06dde243c9f273427ef262c25fbe11f;hpb=aa12380008323e14f8d7dabe78b174b72f69e2dd

diff --git a/ccan/tdb2/tdb.c b/ccan/tdb2/tdb.c
index 1aa3baa4..2315c485 100644
--- a/ccan/tdb2/tdb.c
+++ b/ccan/tdb2/tdb.c
@@ -1,4 +1,5 @@
 #include "private.h"
+#include <ccan/asprintf/asprintf.h>
 #include <ccan/tdb2/tdb2.h>
 #include <assert.h>
 #include <stdarg.h>
@@ -49,8 +50,6 @@ static uint64_t random_number(struct tdb_context *tdb)
 	fd = open("/dev/urandom", O_RDONLY);
 	if (fd >= 0) {
 		if (read_all(fd, &ret, sizeof(ret))) {
-			tdb_logerr(tdb, TDB_SUCCESS, TDB_DEBUG_TRACE,
-				 "tdb_open: random from /dev/urandom");
 			close(fd);
 			return ret;
 		}
@@ -65,9 +64,6 @@ static uint64_t random_number(struct tdb_context *tdb)
 			char reply[1 + sizeof(uint64_t)];
 			int r = read(fd, reply, sizeof(reply));
 			if (r > 1) {
-				tdb_logerr(tdb, TDB_SUCCESS, TDB_DEBUG_TRACE,
-					   "tdb_open: %u random bytes from"
-					   " /dev/egd-pool", r-1);
 				/* Copy at least some bytes. */
 				memcpy(&ret, reply+1, r - 1);
 				if (reply[0] == sizeof(uint64_t)
@@ -83,7 +79,7 @@ static uint64_t random_number(struct tdb_context *tdb)
 	/* Fallback: pid and time. */
 	gettimeofday(&now, NULL);
 	ret = getpid() * 100132289ULL + now.tv_sec * 1000000ULL + now.tv_usec;
-	tdb_logerr(tdb, TDB_SUCCESS, TDB_DEBUG_TRACE,
+	tdb_logerr(tdb, TDB_SUCCESS, TDB_LOG_WARNING,
 		   "tdb_open: random from getpid and time");
 	return ret;
 }
@@ -94,14 +90,15 @@ struct new_database {
 };
 
 /* initialise a new database */
-static int tdb_new_database(struct tdb_context *tdb,
-			    struct tdb_attribute_seed *seed,
-			    struct tdb_header *hdr)
+static enum TDB_ERROR tdb_new_database(struct tdb_context *tdb,
+				       struct tdb_attribute_seed *seed,
+				       struct tdb_header *hdr)
 {
 	/* We make it up in memory, then write it out if not internal */
 	struct new_database newdb;
 	unsigned int magic_len;
 	ssize_t rlen;
+	enum TDB_ERROR ecode;
 
 	/* Fill in the header */
 	newdb.hdr.version = TDB_VERSION;
@@ -122,9 +119,13 @@ static int tdb_new_database(struct tdb_context *tdb,
 	/* Free is empty. */
 	newdb.hdr.free_table = offsetof(struct new_database, ftable);
 	memset(&newdb.ftable, 0, sizeof(newdb.ftable));
-	set_header(NULL, &newdb.ftable.hdr, TDB_FTABLE_MAGIC, 0,
-		   sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
-		   sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr), 0);
+	ecode = set_header(NULL, &newdb.ftable.hdr, TDB_FTABLE_MAGIC, 0,
+			   sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
+			   sizeof(newdb.ftable) - sizeof(newdb.ftable.hdr),
+			   0);
+	if (ecode != TDB_SUCCESS) {
+		return ecode;
+	}
 
 	/* Magic food */
 	memset(newdb.hdr.magic_food, 0, sizeof(newdb.hdr.magic_food));
@@ -141,29 +142,34 @@ static int tdb_new_database(struct tdb_context *tdb,
 		tdb->map_size = sizeof(newdb);
 		tdb->map_ptr = malloc(tdb->map_size);
 		if (!tdb->map_ptr) {
-			tdb_logerr(tdb, TDB_ERR_OOM, TDB_DEBUG_FATAL,
-				   "tdb_new_database: failed to allocate");
-			return -1;
+			return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
+					  "tdb_new_database:"
+					  " failed to allocate");
 		}
 		memcpy(tdb->map_ptr, &newdb, tdb->map_size);
-		return 0;
+		return TDB_SUCCESS;
+	}
+	if (lseek(tdb->fd, 0, SEEK_SET) == -1) {
+		return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+				  "tdb_new_database:"
+				  " failed to seek: %s", strerror(errno));
 	}
-	if (lseek(tdb->fd, 0, SEEK_SET) == -1)
-		return -1;
 
-	if (ftruncate(tdb->fd, 0) == -1)
-		return -1;
+	if (ftruncate(tdb->fd, 0) == -1) {
+		return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+				  "tdb_new_database:"
+				  " failed to truncate: %s", strerror(errno));
+	}
 
 	rlen = write(tdb->fd, &newdb, sizeof(newdb));
 	if (rlen != sizeof(newdb)) {
 		if (rlen >= 0)
 			errno = ENOSPC;
-		tdb_logerr(tdb, TDB_ERR_IO, TDB_DEBUG_FATAL,
-			   "tdb_new_database: %zi writing header: %s",
-			   rlen, strerror(errno));
-		return -1;
+		return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+				  "tdb_new_database: %zi writing header: %s",
+				  rlen, strerror(errno));
 	}
-	return 0;
+	return TDB_SUCCESS;
 }
 
 struct tdb_context *tdb_open(const char *name, int tdb_flags,
@@ -178,6 +184,8 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 	ssize_t rlen;
 	struct tdb_header hdr;
 	struct tdb_attribute_seed *seed = NULL;
+	tdb_bool_err berr;
+	enum TDB_ERROR ecode;
 
 	tdb = malloc(sizeof(*tdb));
 	if (!tdb) {
@@ -190,7 +198,6 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 	tdb->direct_access = 0;
 	tdb->fd = -1;
 	tdb->map_size = sizeof(struct tdb_header);
-	tdb->ecode = TDB_SUCCESS;
 	tdb->flags = tdb_flags;
 	tdb->logfn = NULL;
 	tdb->transaction = NULL;
@@ -220,24 +227,25 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 				tdb->stats->size = sizeof(attr->stats);
 			break;
 		default:
-			tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_DEBUG_ERROR,
-				   "tdb_open: unknown attribute type %u",
-				   attr->base.attr);
+			ecode = tdb_logerr(tdb, TDB_ERR_EINVAL,
+					   TDB_LOG_USE_ERROR,
+					   "tdb_open:"
+					   " unknown attribute type %u",
+					   attr->base.attr);
 			goto fail;
 		}
 		attr = attr->base.next;
 	}
 
 	if ((open_flags & O_ACCMODE) == O_WRONLY) {
-		tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_DEBUG_ERROR,
-			   "tdb_open: can't open tdb %s write-only", name);
+		ecode = tdb_logerr(tdb, TDB_ERR_EINVAL, TDB_LOG_USE_ERROR,
+				   "tdb_open: can't open tdb %s write-only",
+				   name);
 		goto fail;
 	}
 
 	if ((open_flags & O_ACCMODE) == O_RDONLY) {
 		tdb->read_only = true;
-		/* read only databases don't do locking */
-		tdb->flags |= TDB_NOLOCK;
 		tdb->mmap_flags = PROT_READ;
 	} else {
 		tdb->read_only = false;
@@ -247,7 +255,8 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 	/* internal databases don't need any of the rest. */
 	if (tdb->flags & TDB_INTERNAL) {
 		tdb->flags |= (TDB_NOLOCK | TDB_NOMMAP);
-		if (tdb_new_database(tdb, seed, &hdr) != 0) {
+		ecode = tdb_new_database(tdb, seed, &hdr);
+		if (ecode != TDB_SUCCESS) {
 			goto fail;
 		}
 		tdb_convert(tdb, &hdr.hash_seed, sizeof(hdr.hash_seed));
@@ -259,9 +268,9 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 	if ((tdb->fd = open(name, open_flags, mode)) == -1) {
 		/* errno set by open(2) */
 		saved_errno = errno;
-		tdb_logerr(tdb, TDB_ERR_IO, TDB_DEBUG_ERROR,
-			   "tdb_open: could not open file %s: %s",
-			   name, strerror(errno));
+		ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+				   "tdb_open: could not open file %s: %s",
+				   name, strerror(errno));
 		goto fail;
 	}
 
@@ -270,27 +279,27 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
         fcntl(tdb->fd, F_SETFD, v | FD_CLOEXEC);
 
 	/* ensure there is only one process initialising at once */
-	if (tdb_lock_open(tdb, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK) == -1) {
-		/* errno set by tdb_brlock */
-		saved_errno = errno;
+	ecode = tdb_lock_open(tdb, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK);
+	if (ecode != TDB_SUCCESS) {
 		goto fail;
 	}
 
 	/* If they used O_TRUNC, read will return 0. */
 	rlen = read(tdb->fd, &hdr, sizeof(hdr));
 	if (rlen == 0 && (open_flags & O_CREAT)) {
-		if (tdb_new_database(tdb, seed, &hdr) == -1) {
+		ecode = tdb_new_database(tdb, seed, &hdr);
+		if (ecode != TDB_SUCCESS) {
 			goto fail;
 		}
 	} else if (rlen < 0) {
-		tdb_logerr(tdb, TDB_ERR_IO, TDB_DEBUG_ERROR,
-			   "tdb_open: error %s reading %s",
-			   strerror(errno), name);
+		ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+				   "tdb_open: error %s reading %s",
+				   strerror(errno), name);
 		goto fail;
 	} else if (rlen < sizeof(hdr)
 		   || strcmp(hdr.magic_food, TDB_MAGIC_FOOD) != 0) {
-		tdb_logerr(tdb, TDB_ERR_IO, TDB_DEBUG_ERROR,
-			   "tdb_open: %s is not a tdb file", name);
+		ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+				   "tdb_open: %s is not a tdb file", name);
 		goto fail;
 	}
 
@@ -299,9 +308,10 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 			tdb->flags |= TDB_CONVERT;
 		else {
 			/* wrong version */
-			tdb_logerr(tdb, TDB_ERR_IO, TDB_DEBUG_ERROR,
-				   "tdb_open: %s is unknown version 0x%llx",
-				   name, (long long)hdr.version);
+			ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+					   "tdb_open:"
+					   " %s is unknown version 0x%llx",
+					   name, (long long)hdr.version);
 			goto fail;
 		}
 	}
@@ -312,34 +322,35 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 	hash_test = tdb_hash(tdb, &hash_test, sizeof(hash_test));
 	if (hdr.hash_test != hash_test) {
 		/* wrong hash variant */
-		tdb_logerr(tdb, TDB_ERR_IO, TDB_DEBUG_ERROR,
-			   "tdb_open: %s uses a different hash function",
-			   name);
+		ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+				   "tdb_open:"
+				   " %s uses a different hash function",
+				   name);
 		goto fail;
 	}
 
 	if (fstat(tdb->fd, &st) == -1) {
 		saved_errno = errno;
-		tdb_logerr(tdb, TDB_ERR_IO, TDB_DEBUG_ERROR,
-			   "tdb_open: could not stat open %s: %s",
-			   name, strerror(errno));
+		ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+				   "tdb_open: could not stat open %s: %s",
+				   name, strerror(errno));
 		goto fail;
 	}
 
 	/* Is it already in the open list?  If so, fail. */
 	if (tdb_already_open(st.st_dev, st.st_ino)) {
 		/* FIXME */
-		tdb_logerr(tdb, TDB_ERR_NESTING, TDB_DEBUG_ERROR,
-			   "tdb_open: %s (%d,%d) is already open in this"
-			   " process",
-			   name, (int)st.st_dev, (int)st.st_ino);
+		ecode = tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_USE_ERROR,
+				   "tdb_open: %s (%d,%d) is already open"
+				   " in this process",
+				   name, (int)st.st_dev, (int)st.st_ino);
 		goto fail;
 	}
 
 	tdb->name = strdup(name);
 	if (!tdb->name) {
-		tdb_logerr(tdb, TDB_ERR_OOM, TDB_DEBUG_ERROR,
-			   "tdb_open: failed to allocate name");
+		ecode = tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
+				   "tdb_open: failed to allocate name");
 		goto fail;
 	}
 
@@ -351,12 +362,22 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 	tdb->methods->oob(tdb, tdb->map_size + 1, true);
 
 	/* Now it's fully formed, recover if necessary. */
-	if (tdb_needs_recovery(tdb) && tdb_lock_and_recover(tdb) == -1) {
-		goto fail;
+	berr = tdb_needs_recovery(tdb);
+	if (unlikely(berr != false)) {
+		if (berr < 0) {
+			ecode = berr;
+			goto fail;
+		}
+		ecode = tdb_lock_and_recover(tdb);
+		if (ecode != TDB_SUCCESS) {
+			goto fail;
+		}
 	}
 
-	if (tdb_ftable_init(tdb) == -1)
+	ecode = tdb_ftable_init(tdb);
+	if (ecode != TDB_SUCCESS) {
 		goto fail;
+	}
 
 	tdb->next = tdbs;
 	tdbs = tdb;
@@ -365,7 +386,7 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
  fail:
 	/* Map ecode to some logical errno. */
 	if (!saved_errno) {
-		switch (tdb->ecode) {
+		switch (ecode) {
 		case TDB_ERR_CORRUPT:
 		case TDB_ERR_IO:
 			saved_errno = EIO;
@@ -379,9 +400,6 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 		case TDB_ERR_EINVAL:
 			saved_errno = EINVAL;
 			break;
-		case TDB_ERR_NESTING:
-			saved_errno = EBUSY;
-			break;
 		default:
 			saved_errno = EINVAL;
 			break;
@@ -397,91 +415,102 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
 		} else
 			tdb_munmap(tdb);
 	}
+	free(tdb->lockrecs);
 	free((char *)tdb->name);
 	if (tdb->fd != -1)
 		if (close(tdb->fd) != 0)
-			tdb_logerr(tdb, TDB_ERR_IO, TDB_DEBUG_ERROR,
+			tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
 				   "tdb_open: failed to close tdb->fd"
-				   " on error!");
+				   " on error: %s", strerror(errno));
 	free(tdb);
 	errno = saved_errno;
 	return NULL;
 }
 
-static int 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)
+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;
 
-	if (set_header(tdb, rec, TDB_USED_MAGIC, keylen, datalen,
-		       keylen + dataroom, h))
-		return -1;
-
-	return tdb_write_convert(tdb, off, rec, sizeof(*rec));
+	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;
 }
 
-/* Returns -1 on error, 0 on OK */
-static int 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)
+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 (unlikely(new_off == TDB_OFF_ERR))
-		return -1;
+	if (TDB_OFF_IS_ERR(new_off)) {
+		return new_off;
+	}
 
 	/* We didn't like the existing one: remove it. */
 	if (old_off) {
 		add_stat(tdb, frees, 1);
-		add_free_record(tdb, old_off,
-				sizeof(struct tdb_used_record)
-				+ key.dsize + old_room);
-		if (replace_in_hash(tdb, h, new_off) == -1)
-			return -1;
+		ecode = add_free_record(tdb, old_off,
+					sizeof(struct tdb_used_record)
+					+ key.dsize + old_room);
+		if (ecode == TDB_SUCCESS)
+			ecode = replace_in_hash(tdb, h, new_off);
 	} else {
-		if (add_to_hash(tdb, h, new_off) == -1)
-			return -1;
+		ecode = add_to_hash(tdb, h, new_off);
+	}
+	if (ecode != TDB_SUCCESS) {
+		return ecode;
 	}
 
 	new_off += sizeof(struct tdb_used_record);
-	if (tdb->methods->write(tdb, new_off, key.dptr, key.dsize) == -1)
-		return -1;
+	ecode = tdb->methods->twrite(tdb, new_off, key.dptr, key.dsize);
+	if (ecode != TDB_SUCCESS) {
+		return ecode;
+	}
 
 	new_off += key.dsize;
-	if (tdb->methods->write(tdb, new_off, dbuf.dptr, dbuf.dsize) == -1)
-		return -1;
+	ecode = tdb->methods->twrite(tdb, new_off, dbuf.dptr, dbuf.dsize);
+	if (ecode != TDB_SUCCESS) {
+		return ecode;
+	}
 
 	/* FIXME: tdb_increment_seqnum(tdb); */
-	return 0;
+	return TDB_SUCCESS;
 }
 
-int tdb_store(struct tdb_context *tdb,
-	      struct tdb_data key, struct tdb_data dbuf, int flag)
+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;
-	int ret;
+	enum TDB_ERROR ecode;
 
 	off = find_and_lock(tdb, key, F_WRLCK, &h, &rec, NULL);
-	if (unlikely(off == TDB_OFF_ERR))
-		return -1;
+	if (TDB_OFF_IS_ERR(off)) {
+		return off;
+	}
 
 	/* Now we have lock on this hash bucket. */
 	if (flag == TDB_INSERT) {
 		if (off) {
-			tdb->ecode = TDB_ERR_EXISTS;
-			goto fail;
+			ecode = TDB_ERR_EXISTS;
+			goto out;
 		}
 	} else {
 		if (off) {
@@ -489,41 +518,44 @@ int tdb_store(struct tdb_context *tdb,
 				+ rec_extra_padding(&rec);
 			if (old_room >= dbuf.dsize) {
 				/* Can modify in-place.  Easy! */
-				if (update_rec_hdr(tdb, off,
-						   key.dsize, dbuf.dsize,
-						   &rec, h.h))
-					goto fail;
-				if (tdb->methods->write(tdb, off + sizeof(rec)
-							+ key.dsize,
-							dbuf.dptr, dbuf.dsize))
-					goto fail;
+				ecode = update_rec_hdr(tdb, off,
+						       key.dsize, dbuf.dsize,
+						       &rec, h.h);
+				if (ecode != TDB_SUCCESS) {
+					goto out;
+				}
+				ecode = tdb->methods->twrite(tdb,
+							     off + sizeof(rec)
+							     + key.dsize,
+							     dbuf.dptr,
+							     dbuf.dsize);
+				if (ecode != TDB_SUCCESS) {
+					goto out;
+				}
 				tdb_unlock_hashes(tdb, h.hlock_start,
 						  h.hlock_range, F_WRLCK);
-				return 0;
+				return 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 */
-				tdb->ecode = TDB_ERR_NOEXIST;
-				goto fail;
+				ecode = TDB_ERR_NOEXIST;
+				goto out;
 			}
 		}
 	}
 
 	/* If we didn't use the old record, this implies we're growing. */
-	ret = replace_data(tdb, &h, key, dbuf, off, old_room, off != 0);
-	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
-	return ret;
-
-fail:
+	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 -1;
+	return ecode;
 }
 
-int tdb_append(struct tdb_context *tdb,
-	       struct tdb_data key, struct tdb_data dbuf)
+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;
@@ -531,11 +563,12 @@ int tdb_append(struct tdb_context *tdb,
 	tdb_len_t old_room = 0, old_dlen;
 	unsigned char *newdata;
 	struct tdb_data new_dbuf;
-	int ret;
+	enum TDB_ERROR ecode;
 
 	off = find_and_lock(tdb, key, F_WRLCK, &h, &rec, NULL);
-	if (unlikely(off == TDB_OFF_ERR))
-		return -1;
+	if (TDB_OFF_IS_ERR(off)) {
+		return off;
+	}
 
 	if (off) {
 		old_dlen = rec_data_length(&rec);
@@ -543,33 +576,33 @@ int tdb_append(struct tdb_context *tdb,
 
 		/* Fast path: can append in place. */
 		if (rec_extra_padding(&rec) >= dbuf.dsize) {
-			if (update_rec_hdr(tdb, off, key.dsize,
-					   old_dlen + dbuf.dsize, &rec, h.h))
-				goto fail;
+			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;
-			if (tdb->methods->write(tdb, off, dbuf.dptr,
-						dbuf.dsize) == -1)
-				goto fail;
-
-			/* FIXME: tdb_increment_seqnum(tdb); */
-			tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range,
-					  F_WRLCK);
-			return 0;
+			ecode = tdb->methods->twrite(tdb, off, dbuf.dptr,
+						     dbuf.dsize);
+			goto out;
 		}
 
 		/* Slow path. */
 		newdata = malloc(key.dsize + old_dlen + dbuf.dsize);
 		if (!newdata) {
-			tdb_logerr(tdb, TDB_ERR_OOM, TDB_DEBUG_FATAL,
-				   "tdb_append: failed to allocate %zu bytes",
-				   (size_t)(key.dsize+old_dlen+dbuf.dsize));
-			goto fail;
+			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;
 		}
-		if (tdb->methods->read(tdb, off + sizeof(rec) + key.dsize,
-				       newdata, old_dlen) != 0) {
-			free(newdata);
-			goto fail;
+		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;
@@ -580,75 +613,77 @@ int tdb_append(struct tdb_context *tdb,
 	}
 
 	/* If they're using tdb_append(), it implies they're growing record. */
-	ret = replace_data(tdb, &h, key, new_dbuf, off, old_room, true);
-	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
-	free(newdata);
+	ecode = replace_data(tdb, &h, key, new_dbuf, off, old_room, true);
 
-	return ret;
-
-fail:
+out_free_newdata:
+	free(newdata);
+out:
 	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
-	return -1;
+	return ecode;
 }
 
-struct tdb_data tdb_fetch(struct tdb_context *tdb, struct tdb_data key)
+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;
-	struct tdb_data ret;
+	enum TDB_ERROR ecode;
 
 	off = find_and_lock(tdb, key, F_RDLCK, &h, &rec, NULL);
-	if (unlikely(off == TDB_OFF_ERR))
-		return tdb_null;
+	if (TDB_OFF_IS_ERR(off)) {
+		return off;
+	}
 
 	if (!off) {
-		tdb->ecode = TDB_ERR_NOEXIST;
-		ret = tdb_null;
+		ecode = TDB_ERR_NOEXIST;
 	} else {
-		ret.dsize = rec_data_length(&rec);
-		ret.dptr = tdb_alloc_read(tdb, off + sizeof(rec) + key.dsize,
-					  ret.dsize);
+		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 ret;
+	return ecode;
 }
 
-int tdb_delete(struct tdb_context *tdb, struct tdb_data key)
+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 (unlikely(off == TDB_OFF_ERR))
-		return -1;
+	if (TDB_OFF_IS_ERR(off)) {
+		return off;
+	}
 
 	if (!off) {
-		tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
-		tdb->ecode = TDB_ERR_NOEXIST;
-		return -1;
+		ecode = TDB_ERR_NOEXIST;
+		goto unlock;
 	}
 
-	if (delete_from_hash(tdb, &h) == -1)
-		goto unlock_err;
+	ecode = delete_from_hash(tdb, &h);
+	if (ecode != TDB_SUCCESS) {
+		goto unlock;
+	}
 
 	/* Free the deleted entry. */
 	add_stat(tdb, frees, 1);
-	if (add_free_record(tdb, off,
-			    sizeof(struct tdb_used_record)
-			    + rec_key_length(&rec)
-			    + rec_data_length(&rec)
-			    + rec_extra_padding(&rec)) != 0)
-		goto unlock_err;
-
-	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
-	return 0;
+	ecode = add_free_record(tdb, off,
+				sizeof(struct tdb_used_record)
+				+ rec_key_length(&rec)
+				+ rec_data_length(&rec)
+				+ rec_extra_padding(&rec));
 
-unlock_err:
+unlock:
 	tdb_unlock_hashes(tdb, h.hlock_start, h.hlock_range, F_WRLCK);
-	return -1;
+	return ecode;
 }
 
 int tdb_close(struct tdb_context *tdb)
@@ -691,22 +726,16 @@ int tdb_close(struct tdb_context *tdb)
 	return ret;
 }
 
-enum TDB_ERROR tdb_error(const struct tdb_context *tdb)
-{
-	return tdb->ecode;
-}
-
-const char *tdb_errorstr(const struct tdb_context *tdb)
+const char *tdb_errorstr(enum TDB_ERROR ecode)
 {
 	/* Gcc warns if you miss a case in the switch, so use that. */
-	switch (tdb->ecode) {
+	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_NESTING: return "Transaction already started";
 	case TDB_ERR_EINVAL: return "Invalid parameter";
 	case TDB_ERR_NOEXIST: return "Record does not exist";
 	case TDB_ERR_RDONLY: return "write not permitted";
@@ -714,10 +743,10 @@ const char *tdb_errorstr(const struct tdb_context *tdb)
 	return "Invalid error code";
 }
 
-void COLD tdb_logerr(struct tdb_context *tdb,
-		     enum TDB_ERROR ecode,
-		     enum tdb_debug_level level,
-		     const char *fmt, ...)
+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;
@@ -725,26 +754,21 @@ void COLD tdb_logerr(struct tdb_context *tdb,
 	/* tdb_open paths care about errno, so save it. */
 	int saved_errno = errno;
 
-	tdb->ecode = ecode;
-
 	if (!tdb->logfn)
-		return;
+		return ecode;
 
-	/* FIXME: Doesn't assume asprintf. */
 	va_start(ap, fmt);
-	len = vsnprintf(NULL, 0, fmt, ap);
+	len = vasprintf(&message, fmt, ap);
 	va_end(ap);
 
-	message = malloc(len + 1);
-	if (!message) {
-		tdb->logfn(tdb, level, tdb->log_private,
-			   "out of memory formatting message");
-		return;
+	if (len < 0) {
+		tdb->logfn(tdb, TDB_LOG_ERROR, tdb->log_private,
+			   "out of memory formatting message:");
+		tdb->logfn(tdb, level, tdb->log_private, fmt);
+	} else {
+		tdb->logfn(tdb, level, tdb->log_private, message);
+		free(message);
 	}
-	va_start(ap, fmt);
-	len = vsprintf(message, fmt, ap);
-	va_end(ap);
-	tdb->logfn(tdb, level, tdb->log_private, message);
-	free(message);
 	errno = saved_errno;
+	return ecode;
 }