From 17a5871d9d58ea639b6d1ba4f0ce58462d55a33c Mon Sep 17 00:00:00 2001 From: David Rowley Date: Sat, 27 Jul 2024 23:46:07 +1200 Subject: Optimize escaping of JSON strings There were quite a few places where we either had a non-NUL-terminated string or a text Datum which we needed to call escape_json() on. Many of these places required that a temporary string was created due to the fact that escape_json() needs a NUL-terminated cstring. For text types, those first had to be converted to cstring before calling escape_json() on them. Here we introduce two new functions to make escaping JSON more optimal: escape_json_text() can be given a text Datum to append onto the given buffer. This is more optimal as it foregoes the need to convert the text Datum into a cstring. A temporary allocation is only required if the text Datum needs to be detoasted. escape_json_with_len() can be used when the length of the cstring is already known or the given string isn't NUL-terminated. Having this allows various places which were creating a temporary NUL-terminated string to just call escape_json_with_len() without any temporary memory allocations. Discussion: https://postgr.es/m/CAApHDvpLXwMZvbCKcdGfU9XQjGCDm7tFpRdTXuB9PVgpNUYfEQ@mail.gmail.com Reviewed-by: Melih Mutlu, Heikki Linnakangas --- src/include/utils/json.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'src/include/utils/json.h') diff --git a/src/include/utils/json.h b/src/include/utils/json.h index 6d7f1b387d1..79c1062e1bf 100644 --- a/src/include/utils/json.h +++ b/src/include/utils/json.h @@ -18,6 +18,8 @@ /* functions in json.c */ extern void escape_json(StringInfo buf, const char *str); +extern void escape_json_with_len(StringInfo buf, const char *str, int len); +extern void escape_json_text(StringInfo buf, const text *txt); extern char *JsonEncodeDateTime(char *buf, Datum value, Oid typid, const int *tzp); extern bool to_json_is_immutable(Oid typoid); -- cgit v1.2.3