int SLNSessionGetValueForField(SLNSessionRef const session, str_t value[], size_t const max, strarg_t const fileURI, strarg_t const field) {
if(!SLNSessionHasPermission(session, SLN_RDONLY)) return DB_EACCES;
if(!field) return DB_EINVAL;
if(max) value[0] = '\0';
int rc = 0;
DB_cursor *metafiles = NULL;
DB_cursor *values = NULL;
SLNRepoRef const repo = SLNSessionGetRepo(session);
DB_env *db = NULL;
SLNRepoDBOpen(repo, &db);
DB_txn *txn = NULL;
rc = db_txn_begin(db, NULL, DB_RDONLY, &txn);
if(rc < 0) goto done;
rc = db_cursor_open(txn, &metafiles);
if(rc < 0) goto done;
rc = db_cursor_open(txn, &values);
if(rc < 0) goto done;
DB_range metaFileIDs[1];
SLNTargetURIAndMetaFileIDRange1(metaFileIDs, txn, fileURI);
DB_val metaFileID_key[1];
rc = db_cursor_firstr(metafiles, metaFileIDs, metaFileID_key, NULL, +1);
if(rc < 0 && DB_NOTFOUND != rc) goto done;
for(; rc >= 0; rc = db_cursor_nextr(metafiles, metaFileIDs, metaFileID_key, NULL, +1)) {
strarg_t u;
uint64_t metaFileID;
SLNTargetURIAndMetaFileIDKeyUnpack(metaFileID_key, txn, &u, &metaFileID);
assert(0 == strcmp(fileURI, u));
DB_range vrange[1];
SLNMetaFileIDFieldAndValueRange2(vrange, txn, metaFileID, field);
DB_val value_val[1];
rc = db_cursor_firstr(values, vrange, value_val, NULL, +1);
if(rc < 0 && DB_NOTFOUND != rc) goto done;
for(; rc >= 0; rc = db_cursor_nextr(values, vrange, value_val, NULL, +1)) {
uint64_t m;
strarg_t f, v;
SLNMetaFileIDFieldAndValueKeyUnpack(value_val, txn, &m, &f, &v);
assert(metaFileID == m);
assert(0 == strcmp(field, f));
if(!v) continue;
if(0 == strcmp("", v)) continue;
size_t const len = strlen(v);
memcpy(value, v, MIN(len, max-1));
value[MIN(len, max-1)] = '\0';
goto done;
}
}
done:
db_cursor_close(values); values = NULL;
db_cursor_close(metafiles); metafiles = NULL;
db_txn_abort(txn); txn = NULL;
SLNRepoDBClose(repo, &db);
return rc;
}
int SLNSessionGetValueForField(SLNSessionRef const session, DB_txn *const txn, strarg_t const fileURI, strarg_t const field, str_t *out, size_t const max) {
int rc = 0;
DB_cursor *metafiles = NULL;
DB_cursor *values = NULL;
rc = db_cursor_open(txn, &metafiles);
if(rc < 0) goto done;
rc = db_cursor_open(txn, &values);
if(rc < 0) goto done;
DB_range metaFileIDs[1];
SLNTargetURIAndMetaFileIDRange1(metaFileIDs, txn, fileURI);
DB_val metaFileID_key[1];
rc = db_cursor_firstr(metafiles, metaFileIDs, metaFileID_key, NULL, +1);
if(rc < 0 && DB_NOTFOUND != rc) goto done;
for(; rc >= 0; rc = db_cursor_nextr(metafiles, metaFileIDs, metaFileID_key, NULL, +1)) {
strarg_t u;
uint64_t metaFileID;
SLNTargetURIAndMetaFileIDKeyUnpack(metaFileID_key, txn, &u, &metaFileID);
assert(0 == strcmp(fileURI, u));
DB_range vrange[1];
SLNMetaFileIDFieldAndValueRange2(vrange, txn, metaFileID, field);
DB_val value_val[1];
rc = db_cursor_firstr(values, vrange, value_val, NULL, +1);
if(rc < 0 && DB_NOTFOUND != rc) goto done;
for(; rc >= 0; rc = db_cursor_nextr(values, vrange, value_val, NULL, +1)) {
uint64_t m;
strarg_t f, v;
SLNMetaFileIDFieldAndValueKeyUnpack(value_val, txn, &m, &f, &v);
assert(metaFileID == m);
assert(0 == strcmp(field, f));
if(!v || '\0' == v[0]) continue;
strlcpy(out, v, max);
goto done;
}
}
done:
db_cursor_close(values); values = NULL;
db_cursor_close(metafiles); metafiles = NULL;
return rc;
}
int SLNSessionGetNextMetaMapURI(SLNSessionRef const session, strarg_t const targetURI, uint64_t *const metaMapID, str_t *out, size_t const max) {
// TODO: We should handle URI synonyms.
// That might mean accepting a fileID instead of targetURI...
assert(metaMapID);
assert(out);
uint64_t const sessionID = SLNSessionGetID(session);
DB_env *db = NULL;
DB_txn *txn = NULL;
DB_cursor *cursor = NULL;
int rc = 0;
size_t count = 0;
rc = SLNSessionDBOpen(session, SLN_RDONLY, &db);
if(rc < 0) goto cleanup;
rc = db_txn_begin(db, NULL, DB_RDONLY, &txn);
if(rc < 0) goto cleanup;
rc = db_cursor_open(txn, &cursor);
if(rc < 0) goto cleanup;
DB_range range[1];
DB_val key[1];
SLNTargetURISessionIDAndMetaMapIDRange2(range, txn, targetURI, sessionID);
SLNTargetURISessionIDAndMetaMapIDKeyPack(key, txn, targetURI, sessionID, *metaMapID);
rc = db_cursor_seekr(cursor, range, key, NULL, +1);
if(rc < 0) goto cleanup;
strarg_t u;
uint64_t s;
SLNTargetURISessionIDAndMetaMapIDKeyUnpack(key, txn, &u, &s, metaMapID);
DB_val row[1], val[1];
SLNSessionIDAndMetaMapIDToMetaURIAndTargetURIKeyPack(row, txn, sessionID, *metaMapID);
rc = db_get(txn, row, val);
if(rc < 0) goto cleanup;
strarg_t metaURI, t;
SLNSessionIDAndMetaMapIDToMetaURIAndTargetURIValUnpack(val, txn, &metaURI, &t);
db_assert(metaURI);
strlcpy(out, metaURI, max); // TODO: Handle err
cleanup:
db_cursor_close(cursor); cursor = NULL;
db_txn_abort(txn); txn = NULL;
SLNSessionDBClose(session, &db);
if(rc < 0) return rc;
return count;
}
static void add_fulltext(DB_txn *const txn, uint64_t const metaFileID, strarg_t const str, size_t const len) {
if(0 == len) return;
assert(str);
int rc;
sqlite3_tokenizer_module const *fts = NULL;
sqlite3_tokenizer *tokenizer = NULL;
fts_get(&fts, &tokenizer);
sqlite3_tokenizer_cursor *tcur = NULL;
rc = fts->xOpen(tokenizer, str, len, &tcur);
assert(SQLITE_OK == rc);
DB_cursor *cursor = NULL;
rc = db_cursor_open(txn, &cursor);
assert(rc >= 0);
for(;;) {
strarg_t token;
int tlen;
int tpos; // TODO
int ignored1, ignored2;
rc = fts->xNext(tcur, &token, &tlen, &ignored1, &ignored2, &tpos);
if(SQLITE_OK != rc) break;
assert('\0' == token[tlen]); // Assumption
DB_val token_val[1];
SLNTermMetaFileIDAndPositionKeyPack(token_val, txn, token, metaFileID, 0);
// TODO: Record tpos. Requires changes to SLNFulltextFilter so that each document only gets returned once, no matter how many times the token appears within it.
DB_val null = { 0, NULL };
rc = db_cursor_put(cursor, token_val, &null, DB_NOOVERWRITE_FAST);
assert(rc >= 0 || DB_KEYEXIST == rc);
}
db_cursor_close(cursor); cursor = NULL;
fts->xClose(tcur); tcur = NULL;
}