tdb2: rename ->read and ->write functions.

[ccan] / ccan / tdb2 / transaction.c

diff --git a/ccan/tdb2/transaction.c b/ccan/tdb2/transaction.c
index 92658026ac9c006c5e6f9bf31b99f77bb116abc6..66be5bdc8e533cf67c49fddea59e2951ca10e863 100644 (file)
--- a/ccan/tdb2/transaction.c
+++ b/ccan/tdb2/transaction.c
@@ -151,7 +151,8 @@ static int transaction_read(struct tdb_context *tdb, tdb_off_t off, void *buf,
        if (tdb->transaction->num_blocks <= blk ||
            tdb->transaction->blocks[blk] == NULL) {
                /* nope, do a real read */
-               if (tdb->transaction->io_methods->read(tdb, off, buf, len) != 0) {
+               if (tdb->transaction->io_methods->tread(tdb, off, buf, len)
+                   != 0) {
                        goto fail;
                }
                return 0;
@@ -249,9 +250,9 @@ static int transaction_write(struct tdb_context *tdb, tdb_off_t off,
                        if (len2 + (blk * getpagesize()) > tdb->transaction->old_map_size) {
                                len2 = tdb->transaction->old_map_size - (blk * getpagesize());
                        }
-                       if (tdb->transaction->io_methods->read(tdb, blk * getpagesize(),
-                                                              tdb->transaction->blocks[blk],
-                                                              len2) != 0) {
+                       if (tdb->transaction->io_methods->tread(tdb, blk * getpagesize(),
+                                                               tdb->transaction->blocks[blk],
+                                                               len2) != 0) {
                                tdb_logerr(tdb, TDB_ERR_OOM, TDB_DEBUG_FATAL,
                                           "transaction_write: failed to"
                                           " read old block: %s",
@@ -363,10 +364,39 @@ static int transaction_expand_file(struct tdb_context *tdb, tdb_off_t addition)
 }
 
 static void *transaction_direct(struct tdb_context *tdb, tdb_off_t off,
-                               size_t len)
+                               size_t len, bool write_mode)
 {
-       /* FIXME */
-       return NULL;
+       size_t blk = off / getpagesize(), end_blk;
+
+       /* This is wrong for zero-length blocks, but will fail gracefully */
+       end_blk = (off + len - 1) / getpagesize();
+
+       /* Can only do direct if in single block and we've already copied. */
+       if (write_mode) {
+               if (blk != end_blk)
+                       return NULL;
+               if (blk >= tdb->transaction->num_blocks)
+                       return NULL;
+               if (tdb->transaction->blocks[blk] == NULL)
+                       return NULL;
+               return tdb->transaction->blocks[blk] + off % getpagesize();
+       }
+
+       /* Single which we have copied? */
+       if (blk == end_blk
+           && blk < tdb->transaction->num_blocks
+           && tdb->transaction->blocks[blk])
+               return tdb->transaction->blocks[blk] + off % getpagesize();
+
+       /* Otherwise must be all not copied. */
+       while (blk < end_blk) {
+               if (blk >= tdb->transaction->num_blocks)
+                       break;
+               if (tdb->transaction->blocks[blk])
+                       return NULL;
+               blk++;
+       }
+       return tdb->transaction->io_methods->direct(tdb, off, len, false);
 }
 
 static const struct tdb_methods transaction_methods = {
@@ -439,8 +469,8 @@ static void _tdb_transaction_cancel(struct tdb_context *tdb)
                uint64_t invalid = TDB_RECOVERY_INVALID_MAGIC;
 
                /* remove the recovery marker */
-               if (methods->write(tdb, tdb->transaction->magic_offset,
-                                  &invalid, sizeof(invalid)) == -1 ||
+               if (methods->twrite(tdb, tdb->transaction->magic_offset,
+                                   &invalid, sizeof(invalid)) == -1 ||
                    transaction_sync(tdb, tdb->transaction->magic_offset,
                                     sizeof(invalid)) == -1) {
                        tdb_logerr(tdb, tdb->ecode, TDB_DEBUG_FATAL,
@@ -595,7 +625,7 @@ static int tdb_recovery_allocate(struct tdb_context *tdb,
        }
 
        if (recovery_head != 0) {
-               if (methods->read(tdb, recovery_head, &rec, sizeof(rec))) {
+               if (methods->tread(tdb, recovery_head, &rec, sizeof(rec))) {
                        tdb_logerr(tdb, tdb->ecode, TDB_DEBUG_FATAL,
                                 "tdb_recovery_allocate:"
                                 " failed to read recovery record");
@@ -667,8 +697,8 @@ static int tdb_recovery_allocate(struct tdb_context *tdb,
        /* write the recovery header offset and sync - we can sync without a race here
           as the magic ptr in the recovery record has not been set */
        tdb_convert(tdb, &recovery_head, sizeof(recovery_head));
-       if (methods->write(tdb, offsetof(struct tdb_header, recovery),
-                          &recovery_head, sizeof(tdb_off_t)) == -1) {
+       if (methods->twrite(tdb, offsetof(struct tdb_header, recovery),
+                           &recovery_head, sizeof(tdb_off_t)) == -1) {
                tdb_logerr(tdb, tdb->ecode, TDB_DEBUG_FATAL,
                         "tdb_recovery_allocate:"
                         " failed to write recovery head");
@@ -761,9 +791,9 @@ static int transaction_setup_recovery(struct tdb_context *tdb,
                /* the recovery area contains the old data, not the
                   new data, so we have to call the original tdb_read
                   method to get it */
-               if (methods->read(tdb, offset,
-                                 p + sizeof(offset) + sizeof(length),
-                                 length) != 0) {
+               if (methods->tread(tdb, offset,
+                                  p + sizeof(offset) + sizeof(length),
+                                  length) != 0) {
                        free(data);
                        return -1;
                }
@@ -776,8 +806,8 @@ static int transaction_setup_recovery(struct tdb_context *tdb,
        tdb_convert(tdb, p, sizeof(tailer));
 
        /* write the recovery data to the recovery area */
-       if (methods->write(tdb, recovery_offset, data,
-                          sizeof(*rec) + recovery_size) == -1) {
+       if (methods->twrite(tdb, recovery_offset, data,
+                           sizeof(*rec) + recovery_size) == -1) {
                tdb_logerr(tdb, tdb->ecode, TDB_DEBUG_FATAL,
                         "tdb_transaction_setup_recovery:"
                         " failed to write recovery data");
@@ -804,7 +834,7 @@ static int transaction_setup_recovery(struct tdb_context *tdb,
        *magic_offset = recovery_offset + offsetof(struct tdb_recovery_record,
                                                   magic);
 
-       if (methods->write(tdb, *magic_offset, &magic, sizeof(magic)) == -1) {
+       if (methods->twrite(tdb, *magic_offset, &magic, sizeof(magic)) == -1) {
                tdb_logerr(tdb, tdb->ecode, TDB_DEBUG_FATAL,
                         "tdb_transaction_setup_recovery:"
                         " failed to write recovery magic");
@@ -978,8 +1008,8 @@ int tdb_transaction_commit(struct tdb_context *tdb)
                        length = tdb->transaction->last_block_size;
                }
 
-               if (methods->write(tdb, offset, tdb->transaction->blocks[i],
-                                  length) == -1) {
+               if (methods->twrite(tdb, offset, tdb->transaction->blocks[i],
+                                   length) == -1) {
                        tdb_logerr(tdb, tdb->ecode, TDB_DEBUG_FATAL,
                                   "tdb_transaction_commit:"
                                   " write failed during commit");
@@ -1084,8 +1114,8 @@ int tdb_transaction_recover(struct tdb_context *tdb)
        }
 
        /* read the full recovery data */
-       if (tdb->methods->read(tdb, recovery_head + sizeof(rec), data,
-                              rec.len) == -1) {
+       if (tdb->methods->tread(tdb, recovery_head + sizeof(rec), data,
+                               rec.len) == -1) {
                tdb_logerr(tdb, tdb->ecode, TDB_DEBUG_FATAL,
                           "tdb_transaction_recover:"
                           " failed to read recovery data");
@@ -1102,7 +1132,7 @@ int tdb_transaction_recover(struct tdb_context *tdb)
                memcpy(&len, p + sizeof(ofs), sizeof(len));
                p += sizeof(ofs) + sizeof(len);
 
-               if (tdb->methods->write(tdb, ofs, p, len) == -1) {
+               if (tdb->methods->twrite(tdb, ofs, p, len) == -1) {
                        free(data);
                        tdb_logerr(tdb, tdb->ecode, TDB_DEBUG_FATAL,
                                 "tdb_transaction_recover:"