If an error would appear before setting buildstate->index_file_fd = -1

in `InitBuildState` we would try to close that file descriptor (which would be 0)
in `BuildIndexCleanup` function because of condition `if (buildstate->index_file_fd != -1)`
and trying to close fd 0 was crashing the server.
Now we will check if the fd is greater than 0 before closing it.

Author: var77

lantern_hnsw/src/hnsw/build.c

@@ -455,7 +455,7 @@ static void BuildIndexCleanup(ldb_HnswBuildState *buildstate)
         buildstate->external_socket->close(buildstate->external_socket);
     }
 
-    if(buildstate->index_file_fd != -1) {
+    if(buildstate->index_file_fd > 0) {
         // index_file_fd will only exist when we mmap the index file to memory
         if(!buildstate->external && buildstate->index_buffer) {
             int munmap_ret = munmap(buildstate->index_buffer, buildstate->index_buffer_size);

lantern_hnsw/test/expected/hnsw_correct.out

@@ -22,7 +22,6 @@ SELECT
     l2sq_dist(v, '{0,0}') AS dist
 FROM
     small_world;
-WARNING:  this hook is experimental and can cause undefined behaviour
 -- Get the results with the index
 CREATE TEMP TABLE results_w_index AS
 SELECT

lantern_hnsw/test/expected/hnsw_cost_estimate.out

@@ -63,7 +63,6 @@ INFO:  done init usearch index
 INFO:  inserted 0 elements
 INFO:  done saving 0 vectors
 SET _lantern_internal.is_test = true;
-WARNING:  this hook is experimental and can cause undefined behaviour
 SELECT is_cost_estimate_within_error('EXPLAIN SELECT * FROM empty_table ORDER BY v <?> ''{1,2}'' LIMIT 10', 0.47);
 DEBUG:  LANTERN - Query cost estimator
 DEBUG:  LANTERN - ---------------------

lantern_hnsw/test/expected/hnsw_create.out

@@ -71,7 +71,6 @@ CREATE TABLE IF NOT EXISTS sift_base10k (
 \copy sift_base10k (v) FROM '/tmp/lantern/vector_datasets/siftsmall_base_arrays.csv' with csv;
 SET lantern.pgvector_compat=FALSE;
 CREATE INDEX hnsw_idx ON sift_base10k USING lantern_hnsw (v dist_l2sq_ops) WITH (M=2, ef_construction=10, ef=4, dim=128);
-WARNING:  this hook is experimental and can cause undefined behaviour
 INFO:  done init usearch index
 INFO:  inserted 10000 elements
 INFO:  done saving 10000 vectors

lantern_hnsw/test/expected/hnsw_create_expr.out

@@ -67,16 +67,10 @@ SET enable_seqscan = false;
 SET lantern.pgvector_compat=FALSE;
 -- This should success
 CREATE INDEX ON test_table USING lantern_hnsw (int_to_fixed_binary_real_array(id)) WITH (M=2);
-WARNING:  this hook is experimental and can cause undefined behaviour
-WARNING:  this hook is experimental and can cause undefined behaviour
-WARNING:  this hook is experimental and can cause undefined behaviour
-WARNING:  this hook is experimental and can cause undefined behaviour
-WARNING:  this hook is experimental and can cause undefined behaviour
 INFO:  done init usearch index
 INFO:  inserted 3 elements
 INFO:  done saving 3 vectors
 SELECT _lantern_internal.validate_index('test_table_int_to_fixed_binary_real_array_idx', false);
-WARNING:  this hook is experimental and can cause undefined behaviour
 INFO:  validate_index() start for test_table_int_to_fixed_binary_real_array_idx
 INFO:  validate_index() done, no issues found.
  validate_index 

lantern_hnsw/test/expected/hnsw_create_unlogged.out

@@ -51,7 +51,6 @@ CREATE UNLOGGED TABLE IF NOT EXISTS sift_base10k (
 \copy sift_base10k (v) FROM '/tmp/lantern/vector_datasets/siftsmall_base_arrays.csv' with csv;
 SET lantern.pgvector_compat=FALSE;
 CREATE INDEX hnsw_idx ON sift_base10k USING lantern_hnsw (v dist_l2sq_ops) WITH (M=2, ef_construction=10, ef=4, dim=128);
-WARNING:  this hook is experimental and can cause undefined behaviour
 INFO:  done init usearch index
 INFO:  inserted 10000 elements
 INFO:  done saving 10000 vectors

lantern_hnsw/test/expected/hnsw_dist_func.out

@@ -38,7 +38,6 @@ SET enable_seqscan=FALSE;
 SET lantern.pgvector_compat=FALSE;
 -- Verify that the distance functions work (check distances)
 SELECT ROUND(l2sq_dist(v, '{0,1,0}')::numeric, 2) FROM small_world_l2 ORDER BY v <?> '{0,1,0}';
-WARNING:  this hook is experimental and can cause undefined behaviour
  round 
 -------
   0.00

lantern_hnsw/test/expected/hnsw_extras.out

@@ -51,7 +51,6 @@ EXPLAIN (COSTS FALSE) SELECT id FROM sift_base1k order by v <-> :'v777' LIMIT 10
 
 SET lantern.pgvector_compat=FALSE;
 EXPLAIN (COSTS FALSE) SELECT id FROM sift_base1k order by v <?> :'v777' LIMIT 10;
-WARNING:  this hook is experimental and can cause undefined behaviour
                                                                                                                                                                                 QUERY PLAN                                                                                                                                                                                 
 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  Limit

lantern_hnsw/test/expected/hnsw_index_from_file.out

@@ -55,7 +55,6 @@ SELECT * FROM ldb_get_indexes('sift_base1k');
 SET enable_seqscan=FALSE;
 SET lantern.pgvector_compat=FALSE;
 SELECT v AS v777 FROM sift_base1k WHERE id = 777 \gset
-WARNING:  this hook is experimental and can cause undefined behaviour
 EXPLAIN (COSTS FALSE) SELECT ROUND(l2sq_dist(v, :'v777')::numeric, 2) FROM sift_base1k order by v <?> :'v777' LIMIT 10;
                                                                                                                                                                                 QUERY PLAN                                                                                                                                                                                 
 ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

lantern_hnsw/test/expected/hnsw_insert.out

@@ -68,7 +68,6 @@ SET enable_seqscan = false;
 SET lantern.pgvector_compat = false;
 -- Inserting vectors of the same dimension and nulls should work
 INSERT INTO small_world (v) VALUES ('{1,1,2}');
-WARNING:  this hook is experimental and can cause undefined behaviour
 INSERT INTO small_world (v) VALUES (NULL);
 -- Inserting vectors of different dimension should fail
 \set ON_ERROR_STOP off

lantern_hnsw/test/expected/hnsw_insert_unlogged.out

@@ -68,7 +68,6 @@ SET enable_seqscan = false;
 SET lantern.pgvector_compat = false;
 -- Inserting vectors of the same dimension and nulls should work
 INSERT INTO small_world (v) VALUES ('{1,1,2}');
-WARNING:  this hook is experimental and can cause undefined behaviour
 INSERT INTO small_world (v) VALUES (NULL);
 -- Inserting vectors of different dimension should fail
 \set ON_ERROR_STOP off

lantern_hnsw/test/expected/hnsw_operators.out

@@ -8,7 +8,6 @@ INFO:  done saving 2 vectors
 -- should rewrite operator
 SET lantern.pgvector_compat=FALSE;
 SELECT * FROM op_test ORDER BY v <?> ARRAY[1,1,1];
-WARNING:  this hook is experimental and can cause undefined behaviour
     v    
 ---------
  {1,1,1}

lantern_hnsw/test/expected/hnsw_select.out

@@ -43,7 +43,6 @@ SET enable_seqscan=FALSE;
 SET lantern.pgvector_compat=FALSE;
 -- Verify that basic queries still work given our query parser and planner hooks
 SELECT 0 + 1;
-WARNING:  this hook is experimental and can cause undefined behaviour
  ?column? 
 ----------
         1

lantern_hnsw/test/expected/hnsw_todo.out

@@ -22,7 +22,6 @@ INFO:  done init usearch index
 INFO:  inserted 8 elements
 INFO:  done saving 8 vectors
 SELECT _lantern_internal.validate_index('small_world_l2_vector_idx', false);
-WARNING:  this hook is experimental and can cause undefined behaviour
 INFO:  validate_index() start for small_world_l2_vector_idx
 INFO:  validate_index() done, no issues found.
  validate_index 

lantern_hnsw/test/expected/hnsw_vector.out

@@ -10,7 +10,6 @@ RESET client_min_messages;
 SET lantern.pgvector_compat=FALSE;
 -- Verify basic functionality of pgvector
 SELECT '[1,2,3]'::vector;
-WARNING:  this hook is experimental and can cause undefined behaviour
  vector  
 ---------
  [1,2,3]

lantern_hnsw/test/test_runner.sh

@@ -46,6 +46,7 @@ function run_regression_test {
                     -e 's! Average  Peak Memory: [0-9]\{1,\}kB!!' \
                     -e 's! time=[0-9]\+\.[0-9]\+\.\.[0-9]\+\.[0-9]\+!!' | \
                grep -v 'DEBUG:  rehashing catalog cache id' | \
+               grep -v 'WARNING:  this hook is experimental and can cause undefined behaviour' | \
                grep -Gv '^ Planning Time:' | \
                grep -Gv '^ Execution Time:' | \
                # ignore lines in explain(format json) output that differ among pg12-pg16