diff options
Diffstat (limited to 'src/backend/utils/adt/json.c')
| -rw-r--r-- | src/backend/utils/adt/json.c | 156 |
1 files changed, 102 insertions, 54 deletions
diff --git a/src/backend/utils/adt/json.c b/src/backend/utils/adt/json.c index d719a61f16b..be7bc46038f 100644 --- a/src/backend/utils/adt/json.c +++ b/src/backend/utils/adt/json.c @@ -23,6 +23,7 @@ #include "utils/builtins.h" #include "utils/date.h" #include "utils/datetime.h" +#include "utils/fmgroids.h" #include "utils/json.h" #include "utils/jsonfuncs.h" #include "utils/lsyscache.h" @@ -285,9 +286,16 @@ datum_to_json_internal(Datum val, bool is_null, StringInfo result, pfree(jsontext); break; default: - outputstr = OidOutputFunctionCall(outfuncoid, val); - escape_json(result, outputstr); - pfree(outputstr); + /* special-case text types to save useless palloc/memcpy cycles */ + if (outfuncoid == F_TEXTOUT || outfuncoid == F_VARCHAROUT || + outfuncoid == F_BPCHAROUT) + escape_json_text(result, (text *) DatumGetPointer(val)); + else + { + outputstr = OidOutputFunctionCall(outfuncoid, val); + escape_json(result, outputstr); + pfree(outputstr); + } break; } } @@ -1391,7 +1399,6 @@ json_object(PG_FUNCTION_ARGS) count, i; text *rval; - char *v; switch (ndims) { @@ -1434,19 +1441,16 @@ json_object(PG_FUNCTION_ARGS) (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), errmsg("null value not allowed for object key"))); - v = TextDatumGetCString(in_datums[i * 2]); if (i > 0) appendStringInfoString(&result, ", "); - escape_json(&result, v); + escape_json_text(&result, (text *) DatumGetPointer(in_datums[i * 2])); appendStringInfoString(&result, " : "); - pfree(v); if (in_nulls[i * 2 + 1]) appendStringInfoString(&result, "null"); else { - v = TextDatumGetCString(in_datums[i * 2 + 1]); - escape_json(&result, v); - pfree(v); + escape_json_text(&result, + (text *) DatumGetPointer(in_datums[i * 2 + 1])); } } @@ -1483,7 +1487,6 @@ json_object_two_arg(PG_FUNCTION_ARGS) val_count, i; text *rval; - char *v; if (nkdims > 1 || nkdims != nvdims) ereport(ERROR, @@ -1512,20 +1515,15 @@ json_object_two_arg(PG_FUNCTION_ARGS) (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), errmsg("null value not allowed for object key"))); - v = TextDatumGetCString(key_datums[i]); if (i > 0) appendStringInfoString(&result, ", "); - escape_json(&result, v); + escape_json_text(&result, (text *) DatumGetPointer(key_datums[i])); appendStringInfoString(&result, " : "); - pfree(v); if (val_nulls[i]) appendStringInfoString(&result, "null"); else - { - v = TextDatumGetCString(val_datums[i]); - escape_json(&result, v); - pfree(v); - } + escape_json_text(&result, + (text *) DatumGetPointer(val_datums[i])); } appendStringInfoChar(&result, '}'); @@ -1541,50 +1539,100 @@ json_object_two_arg(PG_FUNCTION_ARGS) PG_RETURN_TEXT_P(rval); } +/* + * escape_json_char + * Inline helper function for escape_json* functions + */ +static pg_attribute_always_inline void +escape_json_char(StringInfo buf, char c) +{ + switch (c) + { + case '\b': + appendStringInfoString(buf, "\\b"); + break; + case '\f': + appendStringInfoString(buf, "\\f"); + break; + case '\n': + appendStringInfoString(buf, "\\n"); + break; + case '\r': + appendStringInfoString(buf, "\\r"); + break; + case '\t': + appendStringInfoString(buf, "\\t"); + break; + case '"': + appendStringInfoString(buf, "\\\""); + break; + case '\\': + appendStringInfoString(buf, "\\\\"); + break; + default: + if ((unsigned char) c < ' ') + appendStringInfo(buf, "\\u%04x", (int) c); + else + appendStringInfoCharMacro(buf, c); + break; + } +} /* - * Produce a JSON string literal, properly escaping characters in the text. + * escape_json + * Produce a JSON string literal, properly escaping the NUL-terminated + * cstring. */ void escape_json(StringInfo buf, const char *str) { - const char *p; + appendStringInfoCharMacro(buf, '"'); + + for (; *str != '\0'; str++) + escape_json_char(buf, *str); appendStringInfoCharMacro(buf, '"'); - for (p = str; *p; p++) - { - switch (*p) - { - case '\b': - appendStringInfoString(buf, "\\b"); - break; - case '\f': - appendStringInfoString(buf, "\\f"); - break; - case '\n': - appendStringInfoString(buf, "\\n"); - break; - case '\r': - appendStringInfoString(buf, "\\r"); - break; - case '\t': - appendStringInfoString(buf, "\\t"); - break; - case '"': - appendStringInfoString(buf, "\\\""); - break; - case '\\': - appendStringInfoString(buf, "\\\\"); - break; - default: - if ((unsigned char) *p < ' ') - appendStringInfo(buf, "\\u%04x", (int) *p); - else - appendStringInfoCharMacro(buf, *p); - break; - } - } +} + +/* + * escape_json_with_len + * Produce a JSON string literal, properly escaping the possibly not + * NUL-terminated characters in 'str'. 'len' defines the number of bytes + * from 'str' to process. + */ +void +escape_json_with_len(StringInfo buf, const char *str, int len) +{ appendStringInfoCharMacro(buf, '"'); + + for (int i = 0; i < len; i++) + escape_json_char(buf, str[i]); + + appendStringInfoCharMacro(buf, '"'); +} + +/* + * escape_json_text + * Append 'txt' onto 'buf' and escape using escape_json_with_len. + * + * This is more efficient than calling text_to_cstring and appending the + * result as that could require an additional palloc and memcpy. + */ +void +escape_json_text(StringInfo buf, const text *txt) +{ + /* must cast away the const, unfortunately */ + text *tunpacked = pg_detoast_datum_packed(unconstify(text *, txt)); + int len = VARSIZE_ANY_EXHDR(tunpacked); + char *str; + + str = VARDATA_ANY(tunpacked); + + escape_json_with_len(buf, str, len); + + /* pfree any detoasted values */ + if (tunpacked != txt) + pfree(tunpacked); } /* Semantic actions for key uniqueness check */ |