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);
- }
- return ret;
-}
+ 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++;
-void tdb_access_release(struct tdb_context *tdb, const void *p)
-{
- if (!tdb->map_ptr
- || (char *)p < (char *)tdb->map_ptr
- || (char *)p >= (char *)tdb->map_ptr + tdb->map_size)
- free((void *)p);
+ return ret;
}
-#if 0
-/* write a lump of data at a specified offset */
-static int tdb_write(struct tdb_context *tdb, tdb_off_t off,
- const void *buf, tdb_len_t len)
+void *tdb_access_write(struct tdb_context *tdb,
+ tdb_off_t off, tdb_len_t len, bool convert)
{
- if (len == 0) {
- return 0;
- }
+ void *ret = NULL;
- if (tdb->read_only || tdb->traverse_read) {
- tdb->ecode = TDB_ERR_RDONLY;
- return -1;
- }
-
- if (tdb->methods->tdb_oob(tdb, off + len, 0) != 0)
- return -1;
+ if (likely(!(tdb->flags & TDB_CONVERT)))
+ ret = tdb->methods->direct(tdb, off, len);
- if (tdb->map_ptr) {
- memcpy(off + (char *)tdb->map_ptr, buf, len);
- } else {
- ssize_t written = pwrite(tdb->fd, buf, len, off);
- if ((written != (ssize_t)len) && (written != -1)) {
- /* try once more */
- tdb->ecode = TDB_ERR_IO;
- TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_write: wrote only "
- "%d of %d bytes at %d, trying once more\n",
- (int)written, len, off));
- written = pwrite(tdb->fd, (const char *)buf+written,
- len-written,
- off+written);
- }
- if (written == -1) {
- /* Ensure ecode is set for log fn. */
- tdb->ecode = TDB_ERR_IO;
- TDB_LOG((tdb, TDB_DEBUG_FATAL,"tdb_write failed at %d "
- "len=%d (%s)\n", off, len, strerror(errno)));
- return -1;
- } else if (written != (ssize_t)len) {
- tdb->ecode = TDB_ERR_IO;
- TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_write: failed to "
- "write %d bytes at %d in two attempts\n",
- len, off));
- return -1;
+ 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);
}
- }
- return 0;
-}
-
-
+ } else
+ tdb->direct_access++;
-/*
- do an unlocked scan of the hash table heads to find the next non-zero head. The value
- will then be confirmed with the lock held
-*/
-static void tdb_next_hash_chain(struct tdb_context *tdb, uint32_t *chain)
-{
- uint32_t h = *chain;
- if (tdb->map_ptr) {
- for (;h < tdb->header.hash_size;h++) {
- if (0 != *(uint32_t *)(TDB_HASH_TOP(h) + (unsigned char *)tdb->map_ptr)) {
- break;
- }
- }
- } else {
- uint32_t off=0;
- for (;h < tdb->header.hash_size;h++) {
- if (tdb_ofs_read(tdb, TDB_HASH_TOP(h), &off) != 0 || off != 0) {
- break;
- }
- }
- }
- (*chain) = h;
+ return ret;
}
-/* read/write a tdb_off_t */
-int tdb_ofs_read(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d)
+void tdb_access_release(struct tdb_context *tdb, const void *p)
{
- return tdb->methods->tdb_read(tdb, offset, (char*)d, sizeof(*d), DOCONV());
+ if (!tdb->map_ptr
+ || (char *)p < (char *)tdb->map_ptr
+ || (char *)p >= (char *)tdb->map_ptr + tdb->map_size)
+ free((struct tdb_access_hdr *)p - 1);
+ else
+ tdb->direct_access--;
}
-int tdb_ofs_write(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d)
+int tdb_access_commit(struct tdb_context *tdb, void *p)
{
- tdb_off_t off = *d;
- return tdb->methods->tdb_write(tdb, offset, CONVERT(off), sizeof(*d));
-}
+ 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--;
-/* read/write a record */
-int tdb_rec_read(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *rec)
-{
- if (tdb->methods->tdb_read(tdb, offset, rec, sizeof(*rec),DOCONV()) == -1)
- return -1;
- if (TDB_BAD_MAGIC(rec)) {
- /* Ensure ecode is set for log fn. */
- tdb->ecode = TDB_ERR_CORRUPT;
- TDB_LOG((tdb, TDB_DEBUG_FATAL,"tdb_rec_read bad magic 0x%x at offset=%d\n", rec->magic, offset));
- return -1;
- }
- return tdb->methods->tdb_oob(tdb, rec->next+sizeof(*rec), 0);
+ return ret;
}
-int tdb_rec_write(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *rec)
+static void *tdb_direct(struct tdb_context *tdb, tdb_off_t off, size_t len)
{
- struct tdb_record r = *rec;
- return tdb->methods->tdb_write(tdb, offset, CONVERT(r), sizeof(r));
+ if (unlikely(!tdb->map_ptr))
+ return NULL;
+
+ if (unlikely(tdb_oob(tdb, off + len, true) == -1))
+ return NULL;
+ return (char *)tdb->map_ptr + off;
}
-#endif
static const struct tdb_methods io_methods = {
tdb_read,
tdb_write,
tdb_oob,
tdb_expand_file,
+ tdb_direct,
};
/*