Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit03e0bc1

Browse files
committed
Repair bug in regexp split performance improvements.
Commitc8ea87e introduced a temporary conversion buffer forsubstrings extracted during regexp splits. Unfortunately the code thatsized it was failing to ignore the effects of ignored degenerateregexp matches, so for regexp_split_* calls it could under-size thebuffer in such cases.Fix, and add some regression test cases (though those will only catchthe bug if run in a multibyte encoding).Backpatch to 9.3 as the faulty code was.Thanks to the PostGIS project, Regina Obe and Paul Ramsey for thereport (via IRC) and assistance in analysis. Patch by me.
1 parent84a3a1e commit03e0bc1

File tree

3 files changed

+31
-6
lines changed

3 files changed

+31
-6
lines changed

‎src/backend/utils/adt/regexp.c‎

Lines changed: 10 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -936,6 +936,7 @@ setup_regexp_matches(text *orig_str, text *pattern, text *flags,
936936
intarray_len;
937937
intarray_idx;
938938
intprev_match_end;
939+
intprev_valid_match_end;
939940
intstart_search;
940941
intmaxlen=0;/* largest fetch length in characters */
941942

@@ -991,6 +992,7 @@ setup_regexp_matches(text *orig_str, text *pattern, text *flags,
991992

992993
/* search for the pattern, perhaps repeatedly */
993994
prev_match_end=0;
995+
prev_valid_match_end=0;
994996
start_search=0;
995997
while (RE_wchar_execute(cpattern,wide_str,wide_len,start_search,
996998
pmatch_len,pmatch))
@@ -1043,13 +1045,15 @@ setup_regexp_matches(text *orig_str, text *pattern, text *flags,
10431045
matchctx->nmatches++;
10441046

10451047
/*
1046-
* check length of unmatched portion between end of previous match
1047-
* and start of current one
1048+
* check length of unmatched portion between end of previous valid
1049+
* (nondegenerate, or degenerate but not ignored) match and start
1050+
* of current one
10481051
*/
10491052
if (fetching_unmatched&&
10501053
pmatch[0].rm_so >=0&&
1051-
(pmatch[0].rm_so-prev_match_end)>maxlen)
1052-
maxlen= (pmatch[0].rm_so-prev_match_end);
1054+
(pmatch[0].rm_so-prev_valid_match_end)>maxlen)
1055+
maxlen= (pmatch[0].rm_so-prev_valid_match_end);
1056+
prev_valid_match_end=pmatch[0].rm_eo;
10531057
}
10541058
prev_match_end=pmatch[0].rm_eo;
10551059

@@ -1075,8 +1079,8 @@ setup_regexp_matches(text *orig_str, text *pattern, text *flags,
10751079
* input string
10761080
*/
10771081
if (fetching_unmatched&&
1078-
(wide_len-prev_match_end)>maxlen)
1079-
maxlen= (wide_len-prev_match_end);
1082+
(wide_len-prev_valid_match_end)>maxlen)
1083+
maxlen= (wide_len-prev_valid_match_end);
10801084

10811085
/*
10821086
* Keep a note of the end position of the string for the benefit of

‎src/test/regress/expected/strings.out‎

Lines changed: 18 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -674,6 +674,24 @@ SELECT regexp_split_to_array('123456','.');
674674
{"","","","","","",""}
675675
(1 row)
676676

677+
SELECT regexp_split_to_array('123456','');
678+
regexp_split_to_array
679+
-----------------------
680+
{1,2,3,4,5,6}
681+
(1 row)
682+
683+
SELECT regexp_split_to_array('123456','(?:)');
684+
regexp_split_to_array
685+
-----------------------
686+
{1,2,3,4,5,6}
687+
(1 row)
688+
689+
SELECT regexp_split_to_array('1','');
690+
regexp_split_to_array
691+
-----------------------
692+
{1}
693+
(1 row)
694+
677695
-- errors
678696
SELECT foo, length(foo) FROM regexp_split_to_table('thE QUick bROWn FOx jUMPs ovEr The lazy dOG', 'e', 'zippy') AS foo;
679697
ERROR: invalid regexp option: "z"

‎src/test/regress/sql/strings.sql‎

Lines changed: 3 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -188,6 +188,9 @@ SELECT regexp_split_to_array('the quick brown fox jumps over the lazy dog', 'nom
188188
SELECT regexp_split_to_array('123456','1');
189189
SELECT regexp_split_to_array('123456','6');
190190
SELECT regexp_split_to_array('123456','.');
191+
SELECT regexp_split_to_array('123456','');
192+
SELECT regexp_split_to_array('123456','(?:)');
193+
SELECT regexp_split_to_array('1','');
191194
-- errors
192195
SELECT foo, length(foo)FROM regexp_split_to_table('thE QUick bROWn FOx jUMPs ovEr The lazy dOG','e','zippy')AS foo;
193196
SELECT regexp_split_to_array('thE QUick bROWn FOx jUMPs ovEr The lazy dOG','e','iz');

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp