return WERR_OK;
}
- regdb = db_open_trans(NULL, state_path("registry.tdb"), 0,
+ regdb = db_open(NULL, state_path("registry.tdb"), 0,
REG_TDB_FLAGS, O_RDWR, 0600);
if (!regdb) {
- regdb = db_open_trans(NULL, state_path("registry.tdb"), 0,
+ regdb = db_open(NULL, state_path("registry.tdb"), 0,
REG_TDB_FLAGS, O_RDWR|O_CREAT, 0600);
if (!regdb) {
werr = ntstatus_to_werror(map_nt_error_from_unix(errno));
become_root();
- regdb = db_open_trans(NULL, state_path("registry.tdb"), 0,
+ regdb = db_open(NULL, state_path("registry.tdb"), 0,
REG_TDB_FLAGS, O_RDWR, 0600);
if ( !regdb ) {
result = ntstatus_to_werror( map_nt_error_from_unix( errno ) );
/* pack all the strings */
for (i=0; i<num_subkeys; i++) {
- len += tdb_pack(buffer+len, buflen-len, "f",
- regsubkey_ctr_specific_key(ctr, i));
- if (len > buflen) {
- /* allocate some extra space */
- buffer = (uint8 *)SMB_REALLOC(buffer, len*2);
+ size_t thistime;
+
+ thistime = tdb_pack(buffer+len, buflen-len, "f",
+ regsubkey_ctr_specific_key(ctr, i));
+ if (len+thistime > buflen) {
+ size_t thistime2;
+ /*
+ * tdb_pack hasn't done anything because of the short
+ * buffer, allocate extra space.
+ */
+ buffer = SMB_REALLOC_ARRAY(buffer, uint8_t,
+ (len+thistime)*2);
if(buffer == NULL) {
DEBUG(0, ("regdb_store_keys: Failed to realloc "
- "memory of size [%d]\n", len*2));
+ "memory of size [%u]\n",
+ (unsigned int)(len+thistime)*2));
+ ret = false;
+ goto done;
+ }
+ buflen = (len+thistime)*2;
+ thistime2 = tdb_pack(
+ buffer+len, buflen-len, "f",
+ regsubkey_ctr_specific_key(ctr, i));
+ if (thistime2 != thistime) {
+ DEBUG(0, ("tdb_pack failed\n"));
ret = false;
goto done;
}
- buflen = len*2;
- len = tdb_pack(buffer+len, buflen-len, "f",
- regsubkey_ctr_specific_key(ctr, i));
}
+ len += thistime;
}
/* finally write out the data */
goto done;
}
+ /*
+ * Delete a sorted subkey cache for regdb_key_exists, will be
+ * recreated automatically
+ */
+ keyname = talloc_asprintf(ctx, "%s/%s", REG_SORTED_SUBKEYS_PREFIX,
+ keyname);
+ if (keyname != NULL) {
+ dbwrap_delete_bystring(regdb, keyname);
+ }
+
done:
TALLOC_FREE(ctx);
SAFE_FREE(buffer);
return ret;
}
+/*
+ * regdb_key_exists() is a very frequent operation. It can be quite
+ * time-consuming to fully fetch the parent's subkey list, talloc_strdup all
+ * subkeys and then compare the keyname linearly to all the parent's subkeys.
+ *
+ * The following code tries to make this operation as efficient as possible:
+ * Per registry key we create a list of subkeys that is very efficient to
+ * search for existence of a subkey. Its format is:
+ *
+ * 4 bytes num_subkeys
+ * 4*num_subkey bytes offset into the string array
+ * then follows a sorted list of subkeys in uppercase
+ *
+ * This record is created by create_sorted_subkeys() on demand if it does not
+ * exist. scan_parent_subkeys() uses regdb->parse_record to search the sorted
+ * list, the parsing code and the binary search can be found in
+ * parent_subkey_scanner. The code uses parse_record() to avoid a memcpy of
+ * the potentially large subkey record.
+ *
+ * The sorted subkey record is deleted in regdb_store_keys_internal and
+ * recreated on demand.
+ */
+
+static int cmp_keynames(const void *p1, const void *p2)
+{
+ return StrCaseCmp(*((char **)p1), *((char **)p2));
+}
+
+static bool create_sorted_subkeys(const char *key, const char *sorted_keyname)
+{
+ char **sorted_subkeys;
+ REGSUBKEY_CTR *ctr;
+ bool result = false;
+ NTSTATUS status;
+ char *buf;
+ char *p;
+ int i, res;
+ size_t len;
+
+ ctr = talloc(talloc_tos(), REGSUBKEY_CTR);
+ if (ctr == NULL) {
+ return false;
+ }
+
+ res = regdb_fetch_keys(key, ctr);
+ if (res == -1) {
+ goto fail;
+ }
+
+ sorted_subkeys = talloc_array(ctr, char *, ctr->num_subkeys);
+ if (sorted_subkeys == NULL) {
+ goto fail;
+ }
+
+ len = 4 + 4*ctr->num_subkeys;
+
+ for (i = 0; i<ctr->num_subkeys; i++) {
+ sorted_subkeys[i] = talloc_strdup_upper(sorted_subkeys,
+ ctr->subkeys[i]);
+ if (sorted_subkeys[i] == NULL) {
+ goto fail;
+ }
+ len += strlen(sorted_subkeys[i])+1;
+ }
+
+ qsort(sorted_subkeys, ctr->num_subkeys, sizeof(char *), cmp_keynames);
+
+ buf = talloc_array(ctr, char, len);
+ if (buf == NULL) {
+ goto fail;
+ }
+ p = buf + 4 + 4*ctr->num_subkeys;
+
+ SIVAL(buf, 0, ctr->num_subkeys);
+
+ for (i=0; i<ctr->num_subkeys; i++) {
+ ptrdiff_t offset = p - buf;
+ SIVAL(buf, 4 + 4*i, offset);
+ strlcpy(p, sorted_subkeys[i], len-offset);
+ p += strlen(sorted_subkeys[i]) + 1;
+ }
+
+ status = dbwrap_trans_store_bystring(
+ regdb, sorted_keyname, make_tdb_data((uint8_t *)buf, len),
+ TDB_REPLACE);
+ if (!NT_STATUS_IS_OK(status)) {
+ goto fail;
+ }
+
+ result = true;
+ fail:
+ TALLOC_FREE(ctr);
+ return result;
+}
+
+struct scan_subkey_state {
+ char *name;
+ bool scanned;
+ bool found;
+};
+
+static int parent_subkey_scanner(TDB_DATA key, TDB_DATA data,
+ void *private_data)
+{
+ struct scan_subkey_state *state =
+ (struct scan_subkey_state *)private_data;
+ uint32_t num_subkeys;
+ uint32_t l, u;
+
+ if (data.dsize < sizeof(uint32_t)) {
+ return -1;
+ }
+
+ state->scanned = true;
+ state->found = false;
+
+ tdb_unpack(data.dptr, data.dsize, "d", &num_subkeys);
+
+ l = 0;
+ u = num_subkeys;
+
+ while (l < u) {
+ uint32_t idx = (l+u)/2;
+ char *s = (char *)data.dptr + IVAL(data.dptr, 4 + 4*idx);
+ int comparison = strcmp(state->name, s);
+
+ if (comparison < 0) {
+ u = idx;
+ } else if (comparison > 0) {
+ l = idx + 1;
+ } else {
+ state->found = true;
+ return 0;
+ }
+ }
+ return 0;
+}
+
+static bool scan_parent_subkeys(const char *parent, const char *name)
+{
+ char *path = NULL;
+ char *key = NULL;
+ struct scan_subkey_state state = { 0, };
+ bool result = false;
+ int res;
+
+ state.name = NULL;
+
+ path = normalize_reg_path(talloc_tos(), parent);
+ if (path == NULL) {
+ goto fail;
+ }
+
+ key = talloc_asprintf(talloc_tos(), "%s/%s",
+ REG_SORTED_SUBKEYS_PREFIX, path);
+ if (key == NULL) {
+ goto fail;
+ }
+
+ state.name = talloc_strdup_upper(talloc_tos(), name);
+ if (state.name == NULL) {
+ goto fail;
+ }
+ state.scanned = false;
+
+ res = regdb->parse_record(regdb, string_term_tdb_data(key),
+ parent_subkey_scanner, &state);
+
+ if (state.scanned) {
+ result = state.found;
+ } else {
+ if (!create_sorted_subkeys(path, key)) {
+ goto fail;
+ }
+ res = regdb->parse_record(regdb, string_term_tdb_data(key),
+ parent_subkey_scanner, &state);
+ if ((res == 0) && (state.scanned)) {
+ result = state.found;
+ }
+ }
+
+ fail:
+ TALLOC_FREE(path);
+ TALLOC_FREE(state.name);
+ return result;
+}
/**
* Check for the existence of a key.
value = regdb_fetch_key_internal(mem_ctx, path);
ret = (value.dptr != NULL);
} else {
- /* get the list of subkeys of the parent key */
- uint32 num_items, len, i;
- fstring subkeyname;
-
*p = '\0';
- p++;
- value = regdb_fetch_key_internal(mem_ctx, path);
- if (value.dptr == NULL) {
- goto done;
- }
-
- len = tdb_unpack(value.dptr, value.dsize, "d", &num_items);
- for (i = 0; i < num_items; i++) {
- len += tdb_unpack(value.dptr +len, value.dsize -len,
- "f", &subkeyname);
- if (strequal(subkeyname, p)) {
- ret = true;
- goto done;
- }
- }
+ ret = scan_parent_subkeys(path, p+1);
}
done:
int regdb_fetch_keys(const char *key, REGSUBKEY_CTR *ctr)
{
- WERROR werr;
uint32 num_items;
uint8 *buf;
uint32 buflen, len;
buflen = value.dsize;
len = tdb_unpack( buf, buflen, "d", &num_items);
+ /*
+ * The following code breaks the abstraction that reg_objects.c sets
+ * up with regsubkey_ctr_addkey(). But if we use that with the current
+ * data structure of ctr->subkeys being an unsorted array, we end up
+ * with an O(n^2) algorithm for retrieving keys from the tdb
+ * file. This is pretty pointless, as we have to trust the data
+ * structure on disk not to have duplicates anyway. The alternative to
+ * breaking this abstraction would be to set up a more sophisticated
+ * data structure in REGSUBKEY_CTR.
+ *
+ * This makes "net conf list" for a registry with >1000 shares
+ * actually usable :-)
+ */
+
+ ctr->subkeys = talloc_array(ctr, char *, num_items);
+ if (ctr->subkeys == NULL) {
+ DEBUG(5, ("regdb_fetch_keys: could not allocate subkeys\n"));
+ goto done;
+ }
+ ctr->num_subkeys = num_items;
+
for (i=0; i<num_items; i++) {
len += tdb_unpack(buf+len, buflen-len, "f", subkeyname);
- werr = regsubkey_ctr_addkey(ctr, subkeyname);
- if (!W_ERROR_IS_OK(werr)) {
- DEBUG(5, ("regdb_fetch_keys: regsubkey_ctr_addkey "
- "failed: %s\n", dos_errstr(werr)));
+ ctr->subkeys[i] = talloc_strdup(ctr->subkeys, subkeyname);
+ if (ctr->subkeys[i] == NULL) {
+ DEBUG(5, ("regdb_fetch_keys: could not allocate "
+ "subkeyname\n"));
+ TALLOC_FREE(ctr->subkeys);
+ ctr->num_subkeys = 0;
goto done;
}
}
git.samba.org / ira / wip.git / blobdiff