json.h File Reference

#include "lib/stringinfo.h"

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Functions
void	escape_json (StringInfo buf, const char *str)
char *	JsonEncodeDateTime (char *buf, Datum value, Oid typid, const int *tzp)
bool	to_json_is_immutable (Oid typoid)
Datum	json_build_object_worker (int nargs, Datum *args, bool *nulls, Oid *types, bool absent_on_null, bool unique_keys)
Datum	json_build_array_worker (int nargs, Datum *args, bool *nulls, Oid *types, bool absent_on_null)

Function Documentation

escape_json()

void escape_json	(	StringInfo	buf,
		const char *	str
	)

Definition at line 1610 of file json.c.

{
    const char *p;
 
    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;
        }
    }
    appendStringInfoCharMacro(buf, '"');
}

References appendStringInfo(), appendStringInfoCharMacro, appendStringInfoString(), buf, and generate_unaccent_rules::str.

Referenced by AddFileToBackupManifest(), appendJSONKeyValue(), composite_to_json(), datum_to_json(), escape_yaml(), ExplainDummyGroup(), ExplainOpenGroup(), ExplainProperty(), ExplainPropertyList(), ExplainPropertyListNested(), hstore_to_json(), hstore_to_json_loose(), json_object(), json_object_two_arg(), jsonb_put_escaped_value(), populate_scalar(), printJsonPathItem(), sn_object_field_start(), sn_scalar(), transform_string_values_object_field_start(), transform_string_values_scalar(), and write_jsonlog().

json_build_array_worker()

Datum json_build_array_worker	(	int	nargs,
		Datum *	args,
		bool *	nulls,
		Oid *	types,
		bool	absent_on_null
	)

Definition at line 1382 of file json.c.

{
    int         i;
    const char *sep = "";
    StringInfo  result;
 
    result = makeStringInfo();
 
    appendStringInfoChar(result, '[');
 
    for (i = 0; i < nargs; i++)
    {
        if (absent_on_null && nulls[i])
            continue;
 
        appendStringInfoString(result, sep);
        sep = ", ";
        add_json(args[i], nulls[i], result, types[i], false);
    }
 
    appendStringInfoChar(result, ']');
 
    return PointerGetDatum(cstring_to_text_with_len(result->data, result->len));
}

References add_json(), appendStringInfoChar(), appendStringInfoString(), generate_unaccent_rules::args, cstring_to_text_with_len(), StringInfoData::data, i, StringInfoData::len, makeStringInfo(), PointerGetDatum(), and types.

Referenced by ExecEvalJsonConstructor(), and json_build_array().

json_build_object_worker()

Datum json_build_object_worker	(	int	nargs,
		Datum *	args,
		bool *	nulls,
		Oid *	types,
		bool	absent_on_null,
		bool	unique_keys
	)

Definition at line 1269 of file json.c.

{
    int         i;
    const char *sep = "";
    StringInfo  result;
    JsonUniqueBuilderState unique_check;
 
    if (nargs % 2 != 0)
        ereport(ERROR,
                (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("argument list must have even number of elements"),
        /* translator: %s is a SQL function name */
                 errhint("The arguments of %s must consist of alternating keys and values.",
                         "json_build_object()")));
 
    result = makeStringInfo();
 
    appendStringInfoChar(result, '{');
 
    if (unique_keys)
        json_unique_builder_init(&unique_check);
 
    for (i = 0; i < nargs; i += 2)
    {
        StringInfo  out;
        bool        skip;
        int         key_offset;
 
        /* Skip null values if absent_on_null */
        skip = absent_on_null && nulls[i + 1];
 
        if (skip)
        {
            /* If key uniqueness check is needed we must save skipped keys */
            if (!unique_keys)
                continue;
 
            out = json_unique_builder_get_throwawaybuf(&unique_check);
        }
        else
        {
            appendStringInfoString(result, sep);
            sep = ", ";
            out = result;
        }
 
        /* process key */
        if (nulls[i])
            ereport(ERROR,
                    (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
                     errmsg("null value not allowed for object key")));
 
        /* save key offset before appending it */
        key_offset = out->len;
 
        add_json(args[i], false, out, types[i], true);
 
        if (unique_keys)
        {
            /* check key uniqueness after key appending */
            const char *key = &out->data[key_offset];
 
            if (!json_unique_check_key(&unique_check.check, key, 0))
                ereport(ERROR,
                        errcode(ERRCODE_DUPLICATE_JSON_OBJECT_KEY_VALUE),
                        errmsg("duplicate JSON key %s", key));
 
            if (skip)
                continue;
        }
 
        appendStringInfoString(result, " : ");
 
        /* process value */
        add_json(args[i + 1], nulls[i + 1], result, types[i + 1], false);
    }
 
    appendStringInfoChar(result, '}');
 
    return PointerGetDatum(cstring_to_text_with_len(result->data, result->len));
}

References add_json(), appendStringInfoChar(), appendStringInfoString(), generate_unaccent_rules::args, JsonUniqueBuilderState::check, cstring_to_text_with_len(), StringInfoData::data, ereport, errcode(), errhint(), errmsg(), ERROR, i, json_unique_builder_get_throwawaybuf(), json_unique_builder_init(), json_unique_check_key(), sort-test::key, StringInfoData::len, makeStringInfo(), PointerGetDatum(), skip, and types.

Referenced by ExecEvalJsonConstructor(), and json_build_object().

JsonEncodeDateTime()

char* JsonEncodeDateTime	(	char *	buf,
		Datum	value,
		Oid	typid,
		const int *	tzp
	)

Definition at line 385 of file json.c.

{
    if (!buf)
        buf = palloc(MAXDATELEN + 1);
 
    switch (typid)
    {
        case DATEOID:
            {
                DateADT     date;
                struct pg_tm tm;
 
                date = DatumGetDateADT(value);
 
                /* Same as date_out(), but forcing DateStyle */
                if (DATE_NOT_FINITE(date))
                    EncodeSpecialDate(date, buf);
                else
                {
                    j2date(date + POSTGRES_EPOCH_JDATE,
                           &(tm.tm_year), &(tm.tm_mon), &(tm.tm_mday));
                    EncodeDateOnly(&tm, USE_XSD_DATES, buf);
                }
            }
            break;
        case TIMEOID:
            {
                TimeADT     time = DatumGetTimeADT(value);
                struct pg_tm tt,
                           *tm = &tt;
                fsec_t      fsec;
 
                /* Same as time_out(), but forcing DateStyle */
                time2tm(time, tm, &fsec);
                EncodeTimeOnly(tm, fsec, false, 0, USE_XSD_DATES, buf);
            }
            break;
        case TIMETZOID:
            {
                TimeTzADT  *time = DatumGetTimeTzADTP(value);
                struct pg_tm tt,
                           *tm = &tt;
                fsec_t      fsec;
                int         tz;
 
                /* Same as timetz_out(), but forcing DateStyle */
                timetz2tm(time, tm, &fsec, &tz);
                EncodeTimeOnly(tm, fsec, true, tz, USE_XSD_DATES, buf);
            }
            break;
        case TIMESTAMPOID:
            {
                Timestamp   timestamp;
                struct pg_tm tm;
                fsec_t      fsec;
 
                timestamp = DatumGetTimestamp(value);
                /* Same as timestamp_out(), but forcing DateStyle */
                if (TIMESTAMP_NOT_FINITE(timestamp))
                    EncodeSpecialTimestamp(timestamp, buf);
                else if (timestamp2tm(timestamp, NULL, &tm, &fsec, NULL, NULL) == 0)
                    EncodeDateTime(&tm, fsec, false, 0, NULL, USE_XSD_DATES, buf);
                else
                    ereport(ERROR,
                            (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
                             errmsg("timestamp out of range")));
            }
            break;
        case TIMESTAMPTZOID:
            {
                TimestampTz timestamp;
                struct pg_tm tm;
                int         tz;
                fsec_t      fsec;
                const char *tzn = NULL;
 
                timestamp = DatumGetTimestampTz(value);
 
                /*
                 * If a time zone is specified, we apply the time-zone shift,
                 * convert timestamptz to pg_tm as if it were without a time
                 * zone, and then use the specified time zone for converting
                 * the timestamp into a string.
                 */
                if (tzp)
                {
                    tz = *tzp;
                    timestamp -= (TimestampTz) tz * USECS_PER_SEC;
                }
 
                /* Same as timestamptz_out(), but forcing DateStyle */
                if (TIMESTAMP_NOT_FINITE(timestamp))
                    EncodeSpecialTimestamp(timestamp, buf);
                else if (timestamp2tm(timestamp, tzp ? NULL : &tz, &tm, &fsec,
                                      tzp ? NULL : &tzn, NULL) == 0)
                {
                    if (tzp)
                        tm.tm_isdst = 1;    /* set time-zone presence flag */
 
                    EncodeDateTime(&tm, fsec, true, tz, tzn, USE_XSD_DATES, buf);
                }
                else
                    ereport(ERROR,
                            (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
                             errmsg("timestamp out of range")));
            }
            break;
        default:
            elog(ERROR, "unknown jsonb value datetime type oid %u", typid);
            return NULL;
    }
 
    return buf;
}

References buf, DATE_NOT_FINITE, DatumGetDateADT(), DatumGetTimeADT(), DatumGetTimestamp(), DatumGetTimestampTz(), DatumGetTimeTzADTP(), elog(), EncodeDateOnly(), EncodeDateTime(), EncodeSpecialDate(), EncodeSpecialTimestamp(), EncodeTimeOnly(), ereport, errcode(), errmsg(), ERROR, j2date(), MAXDATELEN, palloc(), POSTGRES_EPOCH_JDATE, time2tm(), timestamp2tm(), TIMESTAMP_NOT_FINITE, timetz2tm(), tm, pg_tm::tm_isdst, pg_tm::tm_mday, pg_tm::tm_mon, pg_tm::tm_year, USE_XSD_DATES, USECS_PER_SEC, and value.

Referenced by convertJsonbScalar(), datum_to_json(), and datum_to_jsonb().

to_json_is_immutable()

bool to_json_is_immutable

(

Oid

typoid

)

Definition at line 765 of file json.c.

{
    JsonTypeCategory tcategory;
    Oid         outfuncoid;
 
    json_categorize_type(typoid, &tcategory, &outfuncoid);
 
    switch (tcategory)
    {
        case JSONTYPE_BOOL:
        case JSONTYPE_JSON:
        case JSONTYPE_NULL:
            return true;
 
        case JSONTYPE_DATE:
        case JSONTYPE_TIMESTAMP:
        case JSONTYPE_TIMESTAMPTZ:
            return false;
 
        case JSONTYPE_ARRAY:
            return false;       /* TODO recurse into elements */
 
        case JSONTYPE_COMPOSITE:
            return false;       /* TODO recurse into fields */
 
        case JSONTYPE_NUMERIC:
        case JSONTYPE_CAST:
        case JSONTYPE_OTHER:
            return func_volatile(outfuncoid) == PROVOLATILE_IMMUTABLE;
    }
 
    return false;               /* not reached */
}

References func_volatile(), json_categorize_type(), JSONTYPE_ARRAY, JSONTYPE_BOOL, JSONTYPE_CAST, JSONTYPE_COMPOSITE, JSONTYPE_DATE, JSONTYPE_JSON, JSONTYPE_NULL, JSONTYPE_NUMERIC, JSONTYPE_OTHER, JSONTYPE_TIMESTAMP, and JSONTYPE_TIMESTAMPTZ.

Referenced by contain_mutable_functions_walker().