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| author | David Rowley <drowley@postgresql.org> | 2024-07-27 23:46:07 +1200 |
|---|---|---|
| committer | David Rowley <drowley@postgresql.org> | 2024-07-27 23:46:07 +1200 |
| commit | 17a5871d9d58ea639b6d1ba4f0ce58462d55a33c (patch) | |
| tree | 197ee9a63a458f6980870bb30f75f3693f449aa9 /src/backend/utils/adt/jsonpath.c | |
| parent | 67427f10093a9c50c79e1dbfdcd1698433e8a88f (diff) | |
| download | postgresql-17a5871d9d58ea639b6d1ba4f0ce58462d55a33c.tar.gz postgresql-17a5871d9d58ea639b6d1ba4f0ce58462d55a33c.zip | |
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
Diffstat (limited to 'src/backend/utils/adt/jsonpath.c')
| -rw-r--r-- | src/backend/utils/adt/jsonpath.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/src/backend/utils/adt/jsonpath.c b/src/backend/utils/adt/jsonpath.c index 11e6193e964..0f691bc5f0f 100644 --- a/src/backend/utils/adt/jsonpath.c +++ b/src/backend/utils/adt/jsonpath.c @@ -523,6 +523,8 @@ printJsonPathItem(StringInfo buf, JsonPathItem *v, bool inKey, { JsonPathItem elem; int i; + int32 len; + char *str; check_stack_depth(); CHECK_FOR_INTERRUPTS(); @@ -533,7 +535,8 @@ printJsonPathItem(StringInfo buf, JsonPathItem *v, bool inKey, appendStringInfoString(buf, "null"); break; case jpiString: - escape_json(buf, jspGetString(v, NULL)); + str = jspGetString(v, &len); + escape_json_with_len(buf, str, len); break; case jpiNumeric: if (jspHasNext(v)) @@ -662,7 +665,8 @@ printJsonPathItem(StringInfo buf, JsonPathItem *v, bool inKey, case jpiKey: if (inKey) appendStringInfoChar(buf, '.'); - escape_json(buf, jspGetString(v, NULL)); + str = jspGetString(v, &len); + escape_json_with_len(buf, str, len); break; case jpiCurrent: Assert(!inKey); @@ -674,7 +678,8 @@ printJsonPathItem(StringInfo buf, JsonPathItem *v, bool inKey, break; case jpiVariable: appendStringInfoChar(buf, '$'); - escape_json(buf, jspGetString(v, NULL)); + str = jspGetString(v, &len); + escape_json_with_len(buf, str, len); break; case jpiFilter: appendStringInfoString(buf, "?("); @@ -732,7 +737,9 @@ printJsonPathItem(StringInfo buf, JsonPathItem *v, bool inKey, appendStringInfoString(buf, " like_regex "); - escape_json(buf, v->content.like_regex.pattern); + escape_json_with_len(buf, + v->content.like_regex.pattern, + v->content.like_regex.patternlen); if (v->content.like_regex.flags) { |