License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "private.h"
+#include <assert.h>
#include <ccan/likely/likely.h>
void tdb_munmap(struct tdb_context *tdb)
if (tdb->flags & TDB_NOMMAP)
return;
- tdb->map_ptr = mmap(NULL, tdb->map_size,
- PROT_READ|(tdb->read_only? 0:PROT_WRITE),
+ tdb->map_ptr = mmap(NULL, tdb->map_size, tdb->mmap_flags,
MAP_SHARED, tdb->fd, 0);
/*
struct stat st;
int ret;
+ /* We can't hold pointers during this: we could unmap! */
+ assert(!tdb->direct_access
+ || (tdb->flags & TDB_NOLOCK)
+ || tdb_has_expansion_lock(tdb));
+
if (len <= tdb->map_size)
return 0;
if (tdb->flags & TDB_INTERNAL) {
return 0;
}
-static void *tdb_direct(struct tdb_context *tdb, tdb_off_t off, size_t len)
-{
- if (unlikely(!tdb->map_ptr))
- return NULL;
-
- /* FIXME: We can do a subset of this! */
- if (tdb->transaction)
- return NULL;
-
- if (unlikely(tdb_oob(tdb, off + len, true) == -1))
- return NULL;
- return (char *)tdb->map_ptr + off;
-}
-
/* Either make a copy into pad and return that, or return ptr into mmap. */
/* Note: pad has to be a real object, so we can't get here if len
* overflows size_t */
void *tdb_get(struct tdb_context *tdb, tdb_off_t off, void *pad, size_t len)
{
if (likely(!(tdb->flags & TDB_CONVERT))) {
- void *ret = tdb_direct(tdb, off, len);
+ void *ret = tdb->methods->direct(tdb, off, len);
if (ret)
return ret;
}
return buf;
}
-/* Return first non-zero offset in num offset array, or num. */
/* FIXME: Return the off? */
-uint64_t tdb_find_nonzero_off(struct tdb_context *tdb, tdb_off_t off,
- uint64_t num)
+uint64_t tdb_find_nonzero_off(struct tdb_context *tdb,
+ tdb_off_t base, uint64_t start, uint64_t end)
{
uint64_t i;
const uint64_t *val;
/* Zero vs non-zero is the same unconverted: minor optimization. */
- val = tdb_access_read(tdb, off, num * sizeof(tdb_off_t), false);
+ val = tdb_access_read(tdb, base + start * sizeof(tdb_off_t),
+ (end - start) * sizeof(tdb_off_t), false);
if (!val)
- return num;
+ return end;
- for (i = 0; i < num; i++) {
+ for (i = 0; i < (end - start); i++) {
if (val[i])
break;
}
tdb_access_release(tdb, val);
- return i;
+ return start + i;
}
/* Return first zero offset in num offset array, or num. */
int zero_out(struct tdb_context *tdb, tdb_off_t off, tdb_len_t len)
{
char buf[8192] = { 0 };
- void *p = tdb_direct(tdb, off, len);
+ void *p = tdb->methods->direct(tdb, off, len);
if (p) {
memset(p, 0, len);
return 0;
tdb->ecode = TDB_ERR_IO;
tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv,
"tdb_write failed at %llu len=%llu (%s)\n",
- off, len, strerror(errno));
+ (long long)off, (long long)len,
+ strerror(errno));
return -1;
}
}
return tdb_write_convert(tdb, off, &val, sizeof(val));
}
-/* read a lump of data, allocating the space for it */
-void *tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset, tdb_len_t len)
+static void *_tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset,
+ tdb_len_t len, unsigned int prefix)
{
void *buf;
/* some systems don't like zero length malloc */
- buf = malloc(len ? len : 1);
+ buf = malloc(prefix + len ? prefix + len : 1);
if (unlikely(!buf)) {
tdb->ecode = TDB_ERR_OOM;
tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
"tdb_alloc_read malloc failed len=%lld\n",
- (long long)len);
- } else if (unlikely(tdb->methods->read(tdb, offset, buf, len))) {
+ (long long)prefix + len);
+ } else if (unlikely(tdb->methods->read(tdb, offset, buf+prefix, len))) {
free(buf);
buf = NULL;
}
return buf;
}
-uint64_t hash_record(struct tdb_context *tdb, tdb_off_t off)
+/* read a lump of data, allocating the space for it */
+void *tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset, tdb_len_t len)
{
- struct tdb_used_record pad, *r;
- const void *key;
- uint64_t klen, hash;
-
- r = tdb_get(tdb, off, &pad, sizeof(pad));
- if (!r)
- /* FIXME */
- return 0;
-
- klen = rec_key_length(r);
- key = tdb_access_read(tdb, off + sizeof(pad), klen, false);
- if (!key)
- return 0;
-
- hash = tdb_hash(tdb, key, klen);
- tdb_access_release(tdb, key);
- return hash;
+ return _tdb_alloc_read(tdb, offset, len, 0);
}
static int fill(struct tdb_context *tdb,
return 0;
}
+/* This is only neded for tdb_access_commit, but used everywhere to simplify. */
+struct tdb_access_hdr {
+ tdb_off_t off;
+ tdb_len_t len;
+ bool convert;
+};
+
const void *tdb_access_read(struct tdb_context *tdb,
tdb_off_t off, tdb_len_t len, bool convert)
{
- const void *ret = NULL;
+ const void *ret = NULL;
if (likely(!(tdb->flags & TDB_CONVERT)))
- ret = tdb_direct(tdb, off, len);
+ ret = tdb->methods->direct(tdb, off, len);
if (!ret) {
- ret = tdb_alloc_read(tdb, off, len);
- if (convert)
- tdb_convert(tdb, (void *)ret, len);
- }
+ struct tdb_access_hdr *hdr;
+ hdr = _tdb_alloc_read(tdb, off, len, sizeof(*hdr));
+ if (hdr) {
+ ret = hdr + 1;
+ if (convert)
+ tdb_convert(tdb, (void *)ret, len);
+ }
+ } else
+ tdb->direct_access++;
+
+ return ret;
+}
+
+void *tdb_access_write(struct tdb_context *tdb,
+ tdb_off_t off, tdb_len_t len, bool convert)
+{
+ void *ret = NULL;
+
+ if (likely(!(tdb->flags & TDB_CONVERT)))
+ ret = tdb->methods->direct(tdb, off, len);
+
+ if (!ret) {
+ struct tdb_access_hdr *hdr;
+ hdr = _tdb_alloc_read(tdb, off, len, sizeof(*hdr));
+ if (hdr) {
+ hdr->off = off;
+ hdr->len = len;
+ hdr->convert = convert;
+ ret = hdr + 1;
+ if (convert)
+ tdb_convert(tdb, (void *)ret, len);
+ }
+ } else
+ tdb->direct_access++;
+
return ret;
}
if (!tdb->map_ptr
|| (char *)p < (char *)tdb->map_ptr
|| (char *)p >= (char *)tdb->map_ptr + tdb->map_size)
- free((void *)p);
+ free((struct tdb_access_hdr *)p - 1);
+ else
+ tdb->direct_access--;
+}
+
+int tdb_access_commit(struct tdb_context *tdb, void *p)
+{
+ int ret = 0;
+
+ if (!tdb->map_ptr
+ || (char *)p < (char *)tdb->map_ptr
+ || (char *)p >= (char *)tdb->map_ptr + tdb->map_size) {
+ struct tdb_access_hdr *hdr;
+
+ hdr = (struct tdb_access_hdr *)p - 1;
+ if (hdr->convert)
+ ret = tdb_write_convert(tdb, hdr->off, p, hdr->len);
+ else
+ ret = tdb_write(tdb, hdr->off, p, hdr->len);
+ free(hdr);
+ } else
+ tdb->direct_access--;
+
+ return ret;
}
#if 0
}
#endif
+static void *tdb_direct(struct tdb_context *tdb, tdb_off_t off, size_t len)
+{
+ if (unlikely(!tdb->map_ptr))
+ return NULL;
+
+ if (unlikely(tdb_oob(tdb, off + len, true) == -1))
+ return NULL;
+ return (char *)tdb->map_ptr + off;
+}
+
static const struct tdb_methods io_methods = {
tdb_read,
tdb_write,
tdb_oob,
tdb_expand_file,
+ tdb_direct,
};
/*