*
* json.c
* JSON data type support.
*
* Portions Copyright (c) 2021 Huawei Technologies Co.,Ltd.
* Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* src/backend/utils/adt/json.c
*
* -------------------------------------------------------------------------
*/
#include "postgres.h"
#include "knl/knl_variable.h"
#include "gaussdb_version.h"
#include "access/htup.h"
#include "access/transam.h"
#include "catalog/pg_cast.h"
#include "catalog/pg_type.h"
#include "executor/spi.h"
#include "lib/stringinfo.h"
#include "libpq/pqformat.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "parser/parse_coerce.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/json.h"
#include "utils/jsonapi.h"
#include "utils/typcache.h"
#include "utils/syscache.h"
* The context of the parser is maintained by the recursive descent
* mechanism, but is passed explicitly to the error reporting routine
* for better diagnostics.
*/
typedef enum
{
JSON_PARSE_VALUE,
JSON_PARSE_STRING,
JSON_PARSE_ARRAY_START,
JSON_PARSE_ARRAY_NEXT,
JSON_PARSE_OBJECT_START,
JSON_PARSE_OBJECT_LABEL,
JSON_PARSE_OBJECT_NEXT,
JSON_PARSE_OBJECT_COMMA,
JSON_PARSE_END
} JsonParseContext;
static inline void json_lex(JsonLexContext *lex);
static inline void json_lex_string(JsonLexContext *lex);
static inline void json_lex_number(JsonLexContext *lex, char *s, bool *num_err);
static inline void parse_scalar(JsonLexContext *lex, JsonSemAction *sem);
static void parse_object_field(JsonLexContext *lex, JsonSemAction *sem);
static void parse_object(JsonLexContext *lex, JsonSemAction *sem);
static void parse_array_element(JsonLexContext *lex, JsonSemAction *sem);
static void parse_array(JsonLexContext *lex, JsonSemAction *sem);
static void report_parse_error(JsonParseContext ctx, JsonLexContext *lex);
static void report_invalid_token(JsonLexContext *lex);
static int report_json_context(JsonLexContext *lex);
static char *extract_mb_char(const char *s);
static void composite_to_json(Datum composite, StringInfo result, bool use_line_feeds);
static void array_dim_to_json(StringInfo result, int dim, int ndims, int *dims, Datum *vals, bool *nulls,
int *valcount, TYPCATEGORY tcategory, Oid typoutputfunc, bool use_line_feeds);
static void array_to_json_internal(Datum array, StringInfo result, bool use_line_feeds);
static void datum_to_json(Datum val, bool is_null, StringInfo result, TYPCATEGORY tcategory, Oid typoutputfunc,
bool key_scalar);
static void add_json(Datum val, bool is_null, StringInfo result, Oid val_type, bool key_scalar);
static text *catenate_stringinfo_string(StringInfo buffer, const char *addon);
static JsonSemAction nullSemAction =
{
NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL
};
* lex_peek
*
* what is the current look_ahead token?
*/
static inline JsonTokenType lex_peek(JsonLexContext *lex)
{
return lex->token_type;
}
* lex_accept
*
* accept the look_ahead token and move the lexer to the next token if the
* look_ahead token matches the token parameter. In that case, and if required,
* also hand back the de-escaped lexeme.
*
* returns true if the token matched, false otherwise.
*/
static inline bool lex_accept(JsonLexContext *lex, JsonTokenType token, char **lexeme)
{
if (lex->token_type == token) {
if (lexeme != NULL) {
if (lex->token_type == JSON_TOKEN_STRING) {
if (lex->strval != NULL)
*lexeme = pstrdup(lex->strval->data);
} else {
int len = (lex->token_terminator - lex->token_start);
char *tokstr = (char*)palloc(len + 1);
errno_t rc = 0;
rc = memcpy_s(tokstr, len + 1, lex->token_start, len);
securec_check(rc, "\0", "\0");
tokstr[len] = '\0';
*lexeme = tokstr;
}
}
json_lex(lex);
return true;
}
return false;
}
* lex_accept
*
* move the lexer to the next token if the current look_ahead token matches
* the parameter token. Otherwise, report an error.
*/
static inline void lex_expect(JsonParseContext ctx, JsonLexContext *lex, JsonTokenType token)
{
if (!lex_accept(lex, token, NULL))
report_parse_error(ctx, lex);;
}
* All the defined type categories are upper case , so use lower case here
* so we avoid any possible clash.
*/
#define TYPCATEGORY_JSON 'j'
#define TYPCATEGORY_JSON_CAST 'c'
#define JSON_ALPHANUMERIC_CHAR(c) \
(((c) >= 'a' && (c) <= 'z') || \
((c) >= 'A' && (c) <= 'Z') || \
((c) >= '0' && (c) <= '9') || \
(c) == '_' || \
IS_HIGHBIT_SET(c))
* Input.
*/
Datum json_in(PG_FUNCTION_ARGS)
{
char* json = PG_GETARG_CSTRING(0);
text *result = cstring_to_text(json);
JsonLexContext *lex = NULL;
lex = makeJsonLexContext(result, false);
MemoryContext oldcxt = CurrentMemoryContext;
PG_TRY();
{
pg_parse_json(lex, &nullSemAction);
}
PG_CATCH();
{
if (fcinfo->can_ignore) {
(void)MemoryContextSwitchTo(oldcxt);
ErrorData *edata = CopyErrorData();
ereport(WARNING,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json")));
FlushErrorState();
FreeErrorData(edata);
PG_RETURN_DATUM((Datum)DirectFunctionCall1(json_in, CStringGetDatum("null")));
} else {
PG_RE_THROW();
}
}
PG_END_TRY();
PG_RETURN_TEXT_P(result);
}
* Output.
*/
Datum json_out(PG_FUNCTION_ARGS)
{
Datum txt = PG_GETARG_DATUM(0);
PG_RETURN_CSTRING(TextDatumGetCString(txt));
}
* Binary send.
*/
Datum json_send(PG_FUNCTION_ARGS)
{
text *t = PG_GETARG_TEXT_PP(0);
StringInfoData buf;
pq_begintypsend(&buf);
pq_sendtext(&buf, VARDATA_ANY(t), VARSIZE_ANY_EXHDR(t));
PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
}
* Binary receive.
*/
Datum json_recv(PG_FUNCTION_ARGS)
{
StringInfo buf = (StringInfo) PG_GETARG_POINTER(0);
char *str = NULL;
int nbytes;
JsonLexContext *lex = NULL;
str = pq_getmsgtext(buf, buf->len - buf->cursor, &nbytes);
lex = makeJsonLexContextCstringLen(str, nbytes, false);
pg_parse_json(lex, &nullSemAction);
PG_RETURN_TEXT_P(cstring_to_text_with_len(str, nbytes));
}
* makeJsonLexContext
*
* lex constructor, with or without StringInfo object
* for de-escaped lexemes.
*
* Without is better as it makes the processing faster, so only make one
* if really required.
*
* If you already have the json as a text* value, use the first of these
* functions, otherwise use makeJsonLexContextCstringLen().
*/
JsonLexContext *makeJsonLexContext(text *json, bool need_escapes)
{
return makeJsonLexContextCstringLen(VARDATA(json), VARSIZE(json) - VARHDRSZ, need_escapes);
}
JsonLexContext *makeJsonLexContextCstringLen(char *json, int len, bool need_escapes)
{
JsonLexContext *lex = (JsonLexContext*)palloc0(sizeof(JsonLexContext));
lex->input = lex->token_terminator = lex->line_start = json;
lex->line_number = 1;
lex->input_length = len;
if (need_escapes) {
lex->strval = makeStringInfo();
}
return lex;
}
* pg_parse_json
*
* Publicly visible entry point for the JSON parser.
*
* lex is a lexing context, set up for the json to be processed by calling
* makeJsonLexContext(). sem is a strucure of function pointers to semantic
* action routines to be called at appropriate spots during parsing, and a
* pointer to a state object to be passed to those routines.
*/
void pg_parse_json(JsonLexContext *lex, JsonSemAction *sem)
{
JsonTokenType tok;
json_lex(lex);
tok = lex_peek(lex);
switch (tok)
{
case JSON_TOKEN_OBJECT_START:
parse_object(lex, sem);
break;
case JSON_TOKEN_ARRAY_START:
parse_array(lex, sem);
break;
default:
parse_scalar(lex, sem);
}
lex_expect(JSON_PARSE_END, lex, JSON_TOKEN_END);
}
* Recursive Descent parse routines. There is one for each structural
* element in a json document:
* - scalar (string, number, true, false, null)
* - array ( [ ] )
* - array element
* - object ( { } )
* - object field
*/
static inline void parse_scalar(JsonLexContext *lex, JsonSemAction *sem)
{
char *val = NULL;
json_scalar_action sfunc = sem->scalar;
char **valaddr = NULL;
JsonTokenType tok = lex_peek(lex);
valaddr = sfunc == NULL ? NULL : &val;
switch (tok) {
case JSON_TOKEN_TRUE:
lex_accept(lex, JSON_TOKEN_TRUE, valaddr);
break;
case JSON_TOKEN_FALSE:
lex_accept(lex, JSON_TOKEN_FALSE, valaddr);
break;
case JSON_TOKEN_NULL:
lex_accept(lex, JSON_TOKEN_NULL, valaddr);
break;
case JSON_TOKEN_NUMBER:
lex_accept(lex, JSON_TOKEN_NUMBER, valaddr);
break;
case JSON_TOKEN_STRING:
lex_accept(lex, JSON_TOKEN_STRING, valaddr);
break;
default:
report_parse_error(JSON_PARSE_VALUE, lex);
}
if (sfunc != NULL) {
(*sfunc) (sem->semstate, val, tok);
}
}
static void parse_object_field(JsonLexContext *lex, JsonSemAction *sem)
{
* an object field is "fieldname" : value where value can be a scalar,
* object or array
*/
char *fname = NULL;
json_ofield_action ostart = sem->object_field_start;
json_ofield_action oend = sem->object_field_end;
bool isnull = false;
char **fnameaddr = NULL;
JsonTokenType tok;
if (ostart != NULL || oend != NULL) {
fnameaddr = &fname;
}
if (!lex_accept(lex, JSON_TOKEN_STRING, fnameaddr)) {
report_parse_error(JSON_PARSE_STRING, lex);
}
lex_expect(JSON_PARSE_OBJECT_LABEL, lex, JSON_TOKEN_COLON);
tok = lex_peek(lex);
isnull = tok == JSON_TOKEN_NULL;
if (ostart != NULL) {
(*ostart) (sem->semstate, fname, isnull);
}
switch (tok) {
case JSON_TOKEN_OBJECT_START:
parse_object(lex, sem);
break;
case JSON_TOKEN_ARRAY_START:
parse_array(lex, sem);
break;
default:
parse_scalar(lex, sem);
}
if (oend != NULL) {
(*oend) (sem->semstate, fname, isnull);
}
if (fname != NULL) {
pfree(fname);
}
}
static void parse_object(JsonLexContext *lex, JsonSemAction *sem)
{
* an object is a possibly empty sequence of object fields, separated by
* commas and surrounde by curly braces.
*/
json_struct_action ostart = sem->object_start;
json_struct_action oend = sem->object_end;
JsonTokenType tok;
check_stack_depth();
if (ostart != NULL) {
(*ostart) (sem->semstate);
}
* Data inside an object is at a higher nesting level than the object
* itself. Note that we increment this after we call the semantic routine
* for the object start and restore it before we call the routine for the
* object end.
*/
lex->lex_level++;
lex_expect(JSON_PARSE_OBJECT_START, lex, JSON_TOKEN_OBJECT_START);
tok = lex_peek(lex);
switch (tok) {
case JSON_TOKEN_STRING:
parse_object_field(lex, sem);
while (lex_accept(lex, JSON_TOKEN_COMMA, NULL))
parse_object_field(lex, sem);
break;
case JSON_TOKEN_OBJECT_END:
break;
default:
report_parse_error(JSON_PARSE_OBJECT_START, lex);
}
lex_expect(JSON_PARSE_OBJECT_NEXT, lex, JSON_TOKEN_OBJECT_END);
lex->lex_level--;
if (oend != NULL) {
(*oend) (sem->semstate);
}
}
static void parse_array_element(JsonLexContext *lex, JsonSemAction *sem)
{
json_aelem_action astart = sem->array_element_start;
json_aelem_action aend = sem->array_element_end;
JsonTokenType tok = lex_peek(lex);
bool isnull;
isnull = tok == JSON_TOKEN_NULL;
if (astart != NULL) {
(*astart) (sem->semstate, isnull);
}
switch (tok) {
case JSON_TOKEN_OBJECT_START:
parse_object(lex, sem);
break;
case JSON_TOKEN_ARRAY_START:
parse_array(lex, sem);
break;
default:
parse_scalar(lex, sem);
}
if (aend != NULL) {
(*aend) (sem->semstate, isnull);
}
}
static void parse_array(JsonLexContext *lex, JsonSemAction *sem)
{
* an array is a possibly empty sequence of array elements, separated by
* commas and surrounded by square brackets.
*/
json_struct_action astart = sem->array_start;
json_struct_action aend = sem->array_end;
check_stack_depth();
if (astart != NULL) {
(*astart) (sem->semstate);
}
* Data inside an array is at a higher nesting level than the array
* itself. Note that we increment this after we call the semantic routine
* for the array start and restore it before we call the routine for the
* array end.
*/
lex->lex_level++;
lex_expect(JSON_PARSE_ARRAY_START, lex, JSON_TOKEN_ARRAY_START);
if (lex_peek(lex) != JSON_TOKEN_ARRAY_END) {
parse_array_element(lex, sem);
while (lex_accept(lex, JSON_TOKEN_COMMA, NULL))
parse_array_element(lex, sem);
}
lex_expect(JSON_PARSE_ARRAY_NEXT, lex, JSON_TOKEN_ARRAY_END);
lex->lex_level--;
if (aend != NULL) {
(*aend) (sem->semstate);
}
}
* Lex one token from the input stream.
*/
static inline void json_lex(JsonLexContext *lex)
{
char *s = NULL;
int len;
s = lex->token_terminator;
len = s - lex->input;
while (len < lex->input_length &&
(*s == ' ' || *s == '\t' || *s == '\n' || *s == '\r')){
if (*s == '\n') {
++lex->line_number;
}
++s;
++len;
}
lex->token_start = s;
if (len >= lex->input_length) {
lex->token_start = NULL;
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = s;
lex->token_type = JSON_TOKEN_END;
} else {
switch (*s) {
case '{':
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = s + 1;
lex->token_type = JSON_TOKEN_OBJECT_START;
break;
case '}':
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = s + 1;
lex->token_type = JSON_TOKEN_OBJECT_END;
break;
case '[':
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = s + 1;
lex->token_type = JSON_TOKEN_ARRAY_START;
break;
case ']':
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = s + 1;
lex->token_type = JSON_TOKEN_ARRAY_END;
break;
case ',':
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = s + 1;
lex->token_type = JSON_TOKEN_COMMA;
break;
case ':':
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = s + 1;
lex->token_type = JSON_TOKEN_COLON;
break;
case '"':
json_lex_string(lex);
lex->token_type = JSON_TOKEN_STRING;
break;
case '-':
json_lex_number(lex, s + 1, NULL);
lex->token_type = JSON_TOKEN_NUMBER;
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
json_lex_number(lex, s, NULL);
lex->token_type = JSON_TOKEN_NUMBER;
break;
default: {
char *p = NULL;
* We're not dealing with a string, number, legal
* punctuation mark, or end of string. The only legal
* tokens we might find here are true, false, and null,
* but for error reporting purposes we scan until we see a
* non-alphanumeric character. That way, we can report
* the whole word as an unexpected token, rather than just
* some unintuitive prefix thereof.
*/
for (p = s; p - s < lex->input_length - len && JSON_ALPHANUMERIC_CHAR(*p); p++)
;
* We got some sort of unexpected punctuation or an
* otherwise unexpected character, so just complain about
* that one character.
*/
if (p == s) {
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = s + 1;
report_invalid_token(lex);
}
* We've got a real alphanumeric token here. If it
* happens to be true, false, or null, all is well. If
* not, error out.
*/
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = p;
if (p - s == 4) {
if (memcmp(s, "true", 4) == 0)
lex->token_type = JSON_TOKEN_TRUE;
else if (memcmp(s, "null", 4) == 0)
lex->token_type = JSON_TOKEN_NULL;
else
report_invalid_token(lex);
} else if (p - s == 5 && memcmp(s, "false", 5) == 0) {
lex->token_type = JSON_TOKEN_FALSE;
} else {
report_invalid_token(lex);
}
}
}
}
}
* The next token in the input stream is known to be a string; lex it.
*/
static inline void json_lex_string(JsonLexContext *lex)
{
char *s = NULL;
int len;
int hi_surrogate = -1;
if (lex->strval != NULL) {
resetStringInfo(lex->strval);
}
Assert(lex->input_length > 0);
s = lex->token_start;
len = lex->token_start - lex->input;
for (;;) {
s++;
len++;
if (len >= lex->input_length) {
lex->token_terminator = s;
report_invalid_token(lex);
} else if (*s == '"') {
break;
} else if ((unsigned char) *s < 32) {
lex->token_terminator = s;
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Character with value 0x%02x must be escaped.", (unsigned char) *s),
report_json_context(lex)));
} else if (*s == '\\') {
s++;
len++;
if (len >= lex->input_length) {
lex->token_terminator = s;
report_invalid_token(lex);
} else if (*s == 'u') {
int i;
int ch = 0;
for (i = 1; i <= 4; i++) {
s++;
len++;
if (len >= lex->input_length) {
lex->token_terminator = s;
report_invalid_token(lex);
} else if (*s >= '0' && *s <= '9') {
ch = (ch * 16) + (*s - '0');
} else if (*s >= 'a' && *s <= 'f') {
ch = (ch * 16) + (*s - 'a') + 10;
} else if (*s >= 'A' && *s <= 'F') {
ch = (ch * 16) + (*s - 'A') + 10;
} else {
lex->token_terminator = s + pg_mblen(s);
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("\"\\u\" must be followed by four hexadecimal digits."),
report_json_context(lex)));
}
}
if (lex->strval != NULL) {
char utf8str[5];
int utf8len;
if (ch >= 0xd800 && ch <= 0xdbff) {
if (hi_surrogate != -1) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Unicode high surrogate must not follow a high surrogate."),
report_json_context(lex)));
}
hi_surrogate = ((uint32)ch & 0x3ff) << 10;
continue;
} else if (ch >= 0xdc00 && ch <= 0xdfff) {
if (hi_surrogate == -1) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Unicode low surrogate must follow a high surrogate."),
report_json_context(lex)));
}
ch = 0x10000 + hi_surrogate + ((uint32)ch & 0x3ff);
hi_surrogate = -1;
}
if (hi_surrogate != -1) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Unicode low surrogate must follow a high surrogate."),
report_json_context(lex)));
}
* For UTF8, replace the escape sequence by the actual
* utf8 character in lex->strval. Do this also for other
* encodings if the escape designates an ASCII character,
* otherwise raise an error. We don't ever unescape a
* \u0000, since that would result in an impermissible nul
* byte.
*/
if (ch == 0) {
appendStringInfoString(lex->strval, "\\u0000");
} else if (GetDatabaseEncoding() == PG_UTF8) {
unicode_to_utf8(ch, (unsigned char *) utf8str);
utf8len = pg_utf_mblen((unsigned char *) utf8str);
appendBinaryStringInfo(lex->strval, utf8str, utf8len);
} else if (ch <= 0x007f) {
* This is the only way to designate things like a
* form feed character in JSON, so it's useful in all
* encodings.
*/
appendStringInfoChar(lex->strval, (char) ch);
} else {
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Unicode escape values cannot be used for code point values above 007F when the server encoding is not UTF8."),
report_json_context(lex)));
}
}
} else if (lex->strval != NULL) {
if (hi_surrogate != -1) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Unicode low surrogate must follow a high surrogate."),
report_json_context(lex)));
}
switch (*s) {
case '"':
case '\\':
case '/':
appendStringInfoChar(lex->strval, *s);
break;
case 'b':
appendStringInfoChar(lex->strval, '\b');
break;
case 'f':
appendStringInfoChar(lex->strval, '\f');
break;
case 'n':
appendStringInfoChar(lex->strval, '\n');
break;
case 'r':
appendStringInfoChar(lex->strval, '\r');
break;
case 't':
appendStringInfoChar(lex->strval, '\t');
break;
default:
lex->token_terminator = s + pg_mblen(s);
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Escape sequence \"\\%s\" is invalid.",
extract_mb_char(s)),
report_json_context(lex)));
}
} else if (strchr("\"\\/bfnrt", *s) == NULL) {
* Simpler processing if we're not bothered about de-escaping
*
* It's very tempting to remove the strchr() call here and
* replace it with a switch statement, but testing so far has
* shown it's not a performance win.
*/
lex->token_terminator = s + pg_mblen(s);
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Escape sequence \"\\%s\" is invalid.",
extract_mb_char(s)),
report_json_context(lex)));
}
} else if (lex->strval != NULL) {
if (hi_surrogate != -1) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Unicode low surrogate must follow a high surrogate."),
report_json_context(lex)));
}
appendStringInfoChar(lex->strval, *s);
} else {
int step = pg_mblen(s) - 1;
s += step;
len += step;
}
}
if (hi_surrogate != -1) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Unicode low surrogate must follow a high surrogate."),
report_json_context(lex)));
}
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = s + 1;
}
* The next token in the input stream is known to be a number; lex it.
*
* In JSON, a number consists of four parts:
*
* (1) An optional minus sign ('-').
*
* (2) Either a single '0', or a string of one or more digits that does not
* begin with a '0'.
*
* (3) An optional decimal part, consisting of a period ('.') followed by
* one or more digits. (Note: While this part can be omitted
* completely, it's not OK to have only the decimal point without
* any digits afterwards.)
*
* (4) An optional exponent part, consisting of 'e' or 'E', optionally
* followed by '+' or '-', followed by one or more digits. (Note:
* As with the decimal part, if 'e' or 'E' is present, it must be
* followed by at least one digit.)
*
* The 's' argument to this function points to the ostensible beginning
* of part 2 - i.e. the character after any optional minus sign, and the
* first character of the string if there is none.
*
*-------------------------------------------------------------------------
*/
static inline void json_lex_number(JsonLexContext *lex, char *s, bool *num_err)
{
bool error = false;
char *p = NULL;
int len;
len = s - lex->input;
if (*s == '0') {
s++;
len++;
} else if (*s >= '1' && *s <= '9') {
do {
s++;
len++;
} while (len < lex->input_length && *s >= '0' && *s <= '9');
} else {
error = true;
}
if (len < lex->input_length && *s == '.') {
s++;
len++;
if (len == lex->input_length || *s < '0' || *s > '9') {
error = true;
} else {
do {
s++;
len++;
} while (len < lex->input_length && *s >= '0' && *s <= '9');
}
}
if (len < lex->input_length && (*s == 'e' || *s == 'E')) {
s++;
len++;
if (len < lex->input_length && (*s == '+' || *s == '-')) {
s++;
len++;
}
if (len == lex->input_length || *s < '0' || *s > '9') {
error = true;
} else {
do {
s++;
len++;
} while (len < lex->input_length && *s >= '0' && *s <= '9');
}
}
* Check for trailing garbage. As in json_lex(), any alphanumeric stuff
* here should be considered part of the token for error-reporting
* purposes.
*/
for (p = s; len < lex->input_length && JSON_ALPHANUMERIC_CHAR(*p); p++, len++) {
error = true;
}
if (num_err != NULL) {
*num_err = error;
} else {
lex->prev_token_terminator = lex->token_terminator;
lex->token_terminator = p;
if (error) {
report_invalid_token(lex);
}
}
}
* Report a parse error.
*
* lex->token_start and lex->token_terminator must identify the current token.
*/
static void report_parse_error(JsonParseContext ctx, JsonLexContext *lex)
{
char *token = NULL;
int toklen;
errno_t rc = 0;
if (lex->token_start == NULL || lex->token_type == JSON_TOKEN_END) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("The input string ended unexpectedly."),
report_json_context(lex)));
}
toklen = lex->token_terminator - lex->token_start;
token = (char*)palloc(toklen + 1);
rc = memcpy_s(token, toklen + 1, lex->token_start, toklen);
securec_check(rc, "\0", "\0");
token[toklen] = '\0';
if (ctx == JSON_PARSE_END) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Expected end of input, but found \"%s\".", token),
report_json_context(lex)));
} else {
switch (ctx) {
case JSON_PARSE_VALUE:
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Expected JSON value, but found \"%s\".", token),
report_json_context(lex)));
break;
case JSON_PARSE_STRING:
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Expected string, but found \"%s\".", token),
report_json_context(lex)));
break;
case JSON_PARSE_ARRAY_START:
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Expected array element or \"]\", but found \"%s\".", token),
report_json_context(lex)));
break;
case JSON_PARSE_ARRAY_NEXT:
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Expected \",\" or \"]\", but found \"%s\".", token),
report_json_context(lex)));
break;
case JSON_PARSE_OBJECT_START:
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Expected string or \"}\", but found \"%s\".", token),
report_json_context(lex)));
break;
case JSON_PARSE_OBJECT_LABEL:
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Expected \":\", but found \"%s\".", token),
report_json_context(lex)));
break;
case JSON_PARSE_OBJECT_NEXT:
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Expected \",\" or \"}\", but found \"%s\".", token),
report_json_context(lex)));
break;
case JSON_PARSE_OBJECT_COMMA:
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Expected string, but found \"%s\".", token),
report_json_context(lex)));
break;
default:
elog(ERROR, "unexpected json parse state: %d", ctx);
}
}
}
* Report an invalid input token.
*
* lex->token_start and lex->token_terminator must identify the token.
*/
static void report_invalid_token(JsonLexContext *lex)
{
char *token = NULL;
int toklen;
errno_t rc = 0;
toklen = lex->token_terminator - lex->token_start;
token = (char*)palloc(toklen + 1);
rc = memcpy_s(token, toklen + 1, lex->token_start, toklen);
securec_check(rc, "\0", "\0");
token[toklen] = '\0';
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type json"),
errdetail("Token \"%s\" is invalid.", token),
report_json_context(lex)));
}
* Report a CONTEXT line for bogus JSON input.
*
* lex->token_terminator must be set to identify the spot where we detected
* the error. Note that lex->token_start might be NULL, in case we recognized
* error at EOF.
*
* The return value isn't meaningful, but we make it non-void so that this
* can be invoked inside ereport().
*/
static int report_json_context(JsonLexContext *lex)
{
const char *context_start = NULL;
const char *context_end = NULL;
const char *line_start = NULL;
int line_number;
char *ctxt = NULL;
int ctxtlen;
const char *prefix = NULL;
const char *suffix = NULL;
errno_t rc = 0;
context_start = lex->input;
context_end = lex->token_terminator;
line_start = context_start;
line_number = 1;
for (;;) {
if (context_start < context_end && *context_start == '\n') {
context_start++;
line_start = context_start;
line_number++;
continue;
}
if (context_end - context_start < 50) {
break;
}
if (IS_HIGHBIT_SET(*context_start)) {
context_start += pg_mblen(context_start);
} else {
context_start++;
}
}
* We add "..." to indicate that the excerpt doesn't start at the
* beginning of the line ... but if we're within 3 characters of the
* beginning of the line, we might as well just show the whole line.
*/
if (context_start - line_start <= 3) {
context_start = line_start;
}
ctxtlen = context_end - context_start;
ctxt = (char*)palloc(ctxtlen + 1);
rc = memcpy_s(ctxt, ctxtlen + 1, context_start, ctxtlen);
securec_check(rc, "\0", "\0");
ctxt[ctxtlen] = '\0';
* Show the context, prefixing "..." if not starting at start of line, and
* suffixing "..." if not ending at end of line.
*/
prefix = (context_start > line_start) ? "..." : "";
suffix = (lex->token_type != JSON_TOKEN_END &&
context_end - lex->input < lex->input_length &&
*context_end != '\n' && *context_end != '\r') ? "..." : "";
return errcontext("JSON data, line %d: %s%s%s", line_number, prefix, ctxt, suffix);
}
* Extract a single, possibly multi-byte char from the input string.
*/
static char *extract_mb_char(const char *s)
{
char *res = NULL;
int len;
errno_t rc = 0;
len = pg_mblen(s);
res = (char*)palloc(len + 1);
rc = memcpy_s(res, len + 1, s, len);
securec_check(rc, "\0", "\0");
res[len] = '\0';
return res;
}
* Turn a scalar Datum into JSON, appending the string to "result".
*
* Hand off a non-scalar datum to composite_to_json or array_to_json_internal
* as appropriate.
*/
static void datum_to_json(Datum val, bool is_null, StringInfo result,
TYPCATEGORY tcategory, Oid typoutputfunc, bool key_scalar)
{
char *outputstr = NULL;
text *jsontext = NULL;
bool numeric_error = false;
JsonLexContext dummy_lex;
check_stack_depth();
if (is_null) {
appendStringInfoString(result, "null");
return;
}
switch (tcategory) {
case TYPCATEGORY_ARRAY:
array_to_json_internal(val, result, false);
break;
case TYPCATEGORY_COMPOSITE:
composite_to_json(val, result, false);
break;
case TYPCATEGORY_BOOLEAN:
if (!key_scalar)
appendStringInfoString(result, DatumGetBool(val) ? "true" : "false");
else
escape_json(result, DatumGetBool(val) ? "true" : "false");
break;
case TYPCATEGORY_NUMERIC:
outputstr = OidOutputFunctionCall(typoutputfunc, val);
if (key_scalar) {
escape_json(result, outputstr);
} else {
* Don't call escape_json for a non-key if it's a valid JSON
* number.
*/
dummy_lex.input = *outputstr == '-' ? outputstr + 1 : outputstr;
dummy_lex.input_length = strlen(dummy_lex.input);
json_lex_number(&dummy_lex, dummy_lex.input, &numeric_error);
if (!numeric_error) {
appendStringInfoString(result, outputstr);
} else {
escape_json(result, outputstr);
}
}
pfree(outputstr);
break;
case TYPCATEGORY_JSON:
outputstr = OidOutputFunctionCall(typoutputfunc, val);
appendStringInfoString(result, outputstr);
pfree(outputstr);
break;
case TYPCATEGORY_JSON_CAST:
jsontext = DatumGetTextP(OidFunctionCall1(typoutputfunc, val));
outputstr = text_to_cstring(jsontext);
appendStringInfoString(result, outputstr);
pfree(outputstr);
pfree(jsontext);
break;
default:
outputstr = OidOutputFunctionCall(typoutputfunc, val);
if (key_scalar && *outputstr == '\0') {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("key value must not be empty")));
}
escape_json(result, outputstr);
pfree(outputstr);
break;
}
}
* Process a single dimension of an array.
* If it's the innermost dimension, output the values, otherwise call
* ourselves recursively to process the next dimension.
*/
static void array_dim_to_json(StringInfo result, int dim, int ndims, int *dims, Datum *vals,
bool *nulls, int *valcount, TYPCATEGORY tcategory, Oid typoutputfunc, bool use_line_feeds)
{
int i;
const char *sep = NULL;
Assert(dim < ndims);
sep = use_line_feeds ? ",\n " : ",";
appendStringInfoChar(result, '[');
for (i = 1; i <= dims[dim]; i++) {
if (i > 1) {
appendStringInfoString(result, sep);
}
if (dim + 1 == ndims) {
datum_to_json(vals[*valcount], nulls[*valcount], result, tcategory,
typoutputfunc, false);
(*valcount)++;
} else {
* Do we want line feeds on inner dimensions of arrays? For now
* we'll say no.
*/
array_dim_to_json(result, dim + 1, ndims, dims, vals, nulls,
valcount, tcategory, typoutputfunc, false);
}
}
appendStringInfoChar(result, ']');
}
* Turn an array into JSON.
*/
static void array_to_json_internal(Datum array, StringInfo result, bool use_line_feeds)
{
ArrayType *v = DatumGetArrayTypeP(array);
Oid element_type = ARR_ELEMTYPE(v);
int *dim = NULL;
int ndim;
int nitems;
int count = 0;
Datum *elements = NULL;
bool *nulls = NULL;
int16 typlen;
bool typbyval = false;
char typalign, typdelim;
Oid typioparam;
Oid typoutputfunc;
TYPCATEGORY tcategory;
Oid castfunc = InvalidOid;
ndim = ARR_NDIM(v);
dim = ARR_DIMS(v);
nitems = ArrayGetNItems(ndim, dim);
if (nitems <= 0) {
appendStringInfoString(result, "[]");
return;
}
get_type_io_data(element_type, IOFunc_output,
&typlen, &typbyval, &typalign,
&typdelim, &typioparam, &typoutputfunc);
if (element_type > FirstNormalObjectId) {
HeapTuple tuple;
Form_pg_cast castForm;
tuple = SearchSysCache2(CASTSOURCETARGET, ObjectIdGetDatum(element_type), ObjectIdGetDatum(JSONOID));
if (HeapTupleIsValid(tuple)) {
castForm = (Form_pg_cast) GETSTRUCT(tuple);
if (castForm->castmethod == COERCION_METHOD_FUNCTION) {
castfunc = typoutputfunc = castForm->castfunc;
}
ReleaseSysCache(tuple);
}
}
deconstruct_array(v, element_type, typlen, typbyval, typalign, &elements, &nulls, &nitems);
if (castfunc != InvalidOid) {
tcategory = TYPCATEGORY_JSON_CAST;
} else if (element_type == RECORDOID) {
tcategory = TYPCATEGORY_COMPOSITE;
} else if (element_type == JSONOID || element_type == JSONBOID) {
tcategory = TYPCATEGORY_JSON;
} else {
tcategory = TypeCategory(element_type);
}
array_dim_to_json(result, 0, ndim, dim, elements, nulls, &count, tcategory, typoutputfunc, use_line_feeds);
pfree(elements);
pfree(nulls);
}
* Turn a composite / record into JSON.
*/
static void composite_to_json(Datum composite, StringInfo result, bool use_line_feeds)
{
HeapTupleHeader td;
Oid tupType;
int32 tupTypmod;
TupleDesc tupdesc;
HeapTupleData tmptup;
HeapTupleData *tuple = NULL;
int i;
bool needsep = false;
const char *sep = NULL;
sep = use_line_feeds ? ",\n " : ",";
td = DatumGetHeapTupleHeader(composite);
tupType = HeapTupleHeaderGetTypeId(td);
tupTypmod = HeapTupleHeaderGetTypMod(td);
tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
tmptup.t_len = HeapTupleHeaderGetDatumLength(td);
tmptup.t_data = td;
tuple = &tmptup;
appendStringInfoChar(result, '{');
for (i = 0; i < tupdesc->natts; i++) {
Datum val;
bool isnull = false;
char *attname = NULL;
TYPCATEGORY tcategory;
Oid typoutput;
bool typisvarlena = false;
Oid castfunc = InvalidOid;
if (tupdesc->attrs[i].attisdropped) {
continue;
}
if (needsep) {
appendStringInfoString(result, sep);
}
needsep = true;
attname = NameStr(tupdesc->attrs[i].attname);
escape_json(result, attname);
appendStringInfoChar(result, ':');
val = heap_getattr(tuple, i + 1, tupdesc, &isnull);
getTypeOutputInfo(tupdesc->attrs[i].atttypid, &typoutput, &typisvarlena);
if (tupdesc->attrs[i].atttypid > FirstNormalObjectId) {
HeapTuple cast_tuple;
Form_pg_cast castForm;
cast_tuple = SearchSysCache2(CASTSOURCETARGET, ObjectIdGetDatum(tupdesc->attrs[i].atttypid),
ObjectIdGetDatum(JSONOID));
if (HeapTupleIsValid(cast_tuple)) {
castForm = (Form_pg_cast) GETSTRUCT(cast_tuple);
if (castForm->castmethod == COERCION_METHOD_FUNCTION) {
castfunc = typoutput = castForm->castfunc;
}
ReleaseSysCache(cast_tuple);
}
}
if (castfunc != InvalidOid) {
tcategory = TYPCATEGORY_JSON_CAST;
} else if (tupdesc->attrs[i].atttypid == RECORDARRAYOID) {
tcategory = TYPCATEGORY_ARRAY;
} else if (tupdesc->attrs[i].atttypid == RECORDOID) {
tcategory = TYPCATEGORY_COMPOSITE;
} else if (tupdesc->attrs[i].atttypid == JSONOID || tupdesc->attrs[i].atttypid == JSONBOID) {
tcategory = TYPCATEGORY_JSON;
} else {
tcategory = TypeCategory(tupdesc->attrs[i].atttypid);
}
datum_to_json(val, isnull, result, tcategory, typoutput, false);
}
appendStringInfoChar(result, '}');
ReleaseTupleDesc(tupdesc);
}
* append Json for orig_val to result. If it's a field key, make sure it's
* of an acceptable type and is quoted.
*/
static void add_json(Datum val, bool is_null, StringInfo result, Oid val_type, bool key_scalar)
{
TYPCATEGORY tcategory;
Oid typoutput;
bool typisvarlena = false;
Oid castfunc = InvalidOid;
if (val_type == InvalidOid) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not determine input data type")));
}
getTypeOutputInfo(val_type, &typoutput, &typisvarlena);
if (val_type > FirstNormalObjectId) {
HeapTuple tuple;
Form_pg_cast castForm;
tuple = SearchSysCache2(CASTSOURCETARGET, ObjectIdGetDatum(val_type), ObjectIdGetDatum(JSONOID));
if (HeapTupleIsValid(tuple)) {
castForm = (Form_pg_cast) GETSTRUCT(tuple);
if (castForm->castmethod == COERCION_METHOD_FUNCTION) {
castfunc = typoutput = castForm->castfunc;
}
ReleaseSysCache(tuple);
}
}
if (castfunc != InvalidOid) {
tcategory = TYPCATEGORY_JSON_CAST;
} else if (val_type == RECORDARRAYOID) {
tcategory = TYPCATEGORY_ARRAY;
} else if (val_type == RECORDOID) {
tcategory = TYPCATEGORY_COMPOSITE;
} else if (val_type == JSONOID) {
tcategory = TYPCATEGORY_JSON;
} else {
tcategory = TypeCategory(val_type);
}
if (key_scalar &&
(tcategory == TYPCATEGORY_ARRAY ||
tcategory == TYPCATEGORY_COMPOSITE ||
tcategory == TYPCATEGORY_JSON ||
tcategory == TYPCATEGORY_JSON_CAST)) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("key value must be scalar, not array, composite or json")));
}
datum_to_json(val, is_null, result, tcategory, typoutput, key_scalar);
}
* SQL function array_to_json(row)
*/
extern Datum array_to_json(PG_FUNCTION_ARGS)
{
Datum array = PG_GETARG_DATUM(0);
StringInfo result;
result = makeStringInfo();
array_to_json_internal(array, result, false);
PG_RETURN_TEXT_P(cstring_to_text_with_len(result->data, result->len));
}
* SQL function array_to_json(row, prettybool)
*/
extern Datum array_to_json_pretty(PG_FUNCTION_ARGS)
{
Datum array = PG_GETARG_DATUM(0);
bool use_line_feeds = PG_GETARG_BOOL(1);
StringInfo result;
result = makeStringInfo();
array_to_json_internal(array, result, use_line_feeds);
PG_RETURN_TEXT_P(cstring_to_text_with_len(result->data, result->len));
}
* SQL function row_to_json(row)
*/
extern Datum row_to_json(PG_FUNCTION_ARGS)
{
Datum array = PG_GETARG_DATUM(0);
StringInfo result;
result = makeStringInfo();
composite_to_json(array, result, false);
PG_RETURN_TEXT_P(cstring_to_text_with_len(result->data, result->len));
}
* SQL function row_to_json(row, prettybool)
*/
extern Datum row_to_json_pretty(PG_FUNCTION_ARGS)
{
Datum array = PG_GETARG_DATUM(0);
bool use_line_feeds = PG_GETARG_BOOL(1);
StringInfo result;
result = makeStringInfo();
composite_to_json(array, result, use_line_feeds);
PG_RETURN_TEXT_P(cstring_to_text_with_len(result->data, result->len));
}
* SQL function to_json(anyvalue)
*/
Datum to_json(PG_FUNCTION_ARGS)
{
Datum val = PG_GETARG_DATUM(0);
Oid val_type = get_fn_expr_argtype(fcinfo->flinfo, 0);
StringInfo result;
TYPCATEGORY tcategory;
Oid typoutput;
bool typisvarlena = false;
Oid castfunc = InvalidOid;
if (val_type == InvalidOid) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not determine input data type")));
}
result = makeStringInfo();
getTypeOutputInfo(val_type, &typoutput, &typisvarlena);
if (val_type > FirstNormalObjectId) {
HeapTuple tuple;
Form_pg_cast castForm;
tuple = SearchSysCache2(CASTSOURCETARGET, ObjectIdGetDatum(val_type), ObjectIdGetDatum(JSONOID));
if (HeapTupleIsValid(tuple)) {
castForm = (Form_pg_cast) GETSTRUCT(tuple);
if (castForm->castmethod == COERCION_METHOD_FUNCTION) {
castfunc = typoutput = castForm->castfunc;
}
ReleaseSysCache(tuple);
}
}
if (castfunc != InvalidOid) {
tcategory = TYPCATEGORY_JSON_CAST;
} else if (val_type == RECORDARRAYOID) {
tcategory = TYPCATEGORY_ARRAY;
} else if (val_type == RECORDOID) {
tcategory = TYPCATEGORY_COMPOSITE;
} else if (val_type == JSONOID || val_type == JSONBOID) {
tcategory = TYPCATEGORY_JSON;
} else {
tcategory = TypeCategory(val_type);
}
datum_to_json(val, false, result, tcategory, typoutput, false);
PG_RETURN_TEXT_P(cstring_to_text_with_len(result->data, result->len));
}
* json_agg transition function
*/
Datum json_agg_transfn(PG_FUNCTION_ARGS)
{
Oid val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
MemoryContext aggcontext,
oldcontext;
StringInfo state;
Datum val;
TYPCATEGORY tcategory;
Oid typoutput;
bool typisvarlena = false;
Oid castfunc = InvalidOid;
if (val_type == InvalidOid) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("could not determine input data type")));
}
if (!AggCheckCallContext(fcinfo, &aggcontext)) {
elog(ERROR, "json_agg_transfn called in non-aggregate context");
}
if (PG_ARGISNULL(0)) {
* Make this StringInfo in a context where it will persist for the
* duration off the aggregate call. It's only needed for this initial
* piece, as the StringInfo routines make sure they use the right
* context to enlarge the object if necessary.
*/
oldcontext = MemoryContextSwitchTo(aggcontext);
state = makeStringInfo();
MemoryContextSwitchTo(oldcontext);
appendStringInfoChar(state, '[');
} else {
state = (StringInfo) PG_GETARG_POINTER(0);
appendStringInfoString(state, ", ");
}
if (PG_ARGISNULL(1)) {
val = (Datum) 0;
datum_to_json(val, true, state, 0, InvalidOid, false);
PG_RETURN_POINTER(state);
}
val = PG_GETARG_DATUM(1);
getTypeOutputInfo(val_type, &typoutput, &typisvarlena);
if (val_type > FirstNormalObjectId) {
HeapTuple tuple;
Form_pg_cast castForm;
tuple = SearchSysCache2(CASTSOURCETARGET, ObjectIdGetDatum(val_type), ObjectIdGetDatum(JSONOID));
if (HeapTupleIsValid(tuple)) {
castForm = (Form_pg_cast) GETSTRUCT(tuple);
if (castForm->castmethod == COERCION_METHOD_FUNCTION) {
castfunc = typoutput = castForm->castfunc;
}
ReleaseSysCache(tuple);
}
}
if (castfunc != InvalidOid) {
tcategory = TYPCATEGORY_JSON_CAST;
} else if (val_type == RECORDARRAYOID) {
tcategory = TYPCATEGORY_ARRAY;
} else if (val_type == RECORDOID) {
tcategory = TYPCATEGORY_COMPOSITE;
} else if (val_type == JSONOID || val_type == JSONBOID) {
tcategory = TYPCATEGORY_JSON;
} else {
tcategory = TypeCategory(val_type);
}
if (!PG_ARGISNULL(0) &&
(tcategory == TYPCATEGORY_ARRAY || tcategory == TYPCATEGORY_COMPOSITE)) {
appendStringInfoString(state, "\n ");
}
datum_to_json(val, false, state, tcategory, typoutput, false);
* The transition type for array_agg() is declared to be "internal", which
* is a pass-by-value type the same size as a pointer. So we can safely
* pass the ArrayBuildState pointer through nodeAgg.c's machinations.
*/
PG_RETURN_POINTER(state);
}
* json_agg final function
*/
Datum json_agg_finalfn(PG_FUNCTION_ARGS)
{
StringInfo state;
Assert(AggCheckCallContext(fcinfo, NULL));
state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0);
if (state == NULL) {
PG_RETURN_NULL();
}
PG_RETURN_TEXT_P(catenate_stringinfo_string(state, "]"));
}
* json_object_agg transition function.
*
* aggregate two input columns as a single json value.
*/
Datum json_object_agg_transfn(PG_FUNCTION_ARGS)
{
Oid val_type;
MemoryContext aggcontext, oldcontext;
StringInfo state;
Datum arg;
if (!AggCheckCallContext(fcinfo, &aggcontext)) {
elog(ERROR, "json_agg_transfn called in non-aggregate context");
}
if (PG_ARGISNULL(0)) {
* Make this StringInfo in a context where it will persist for the
* duration off the aggregate call. It's only needed for this initial
* piece, as the StringInfo routines make sure they use the right
* context to enlarge the object if necessary.
*/
oldcontext = MemoryContextSwitchTo(aggcontext);
state = makeStringInfo();
MemoryContextSwitchTo(oldcontext);
appendStringInfoString(state, "{ ");
} else {
state = (StringInfo) PG_GETARG_POINTER(0);
appendStringInfoString(state, ", ");
}
if (PG_ARGISNULL(1)) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("field name must not be null")));
}
val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
* turn a constant (more or less literal) value that's of unknown type
* into text. Unknowns come in as a cstring pointer.
*/
if (val_type == UNKNOWNOID && get_fn_expr_arg_stable(fcinfo->flinfo, 1)) {
val_type = TEXTOID;
arg = CStringGetTextDatum(PG_GETARG_POINTER(1));
} else {
arg = PG_GETARG_DATUM(1);
}
if (val_type == InvalidOid || val_type == UNKNOWNOID) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("arg 1: could not determine data type")));
}
add_json(arg, false, state, val_type, true);
appendStringInfoString(state, " : ");
val_type = get_fn_expr_argtype(fcinfo->flinfo, 2);
if (val_type == UNKNOWNOID && get_fn_expr_arg_stable(fcinfo->flinfo, 2)) {
val_type = TEXTOID;
if (PG_ARGISNULL(2)) {
arg = (Datum) 0;
} else {
arg = CStringGetTextDatum(PG_GETARG_POINTER(2));
}
} else {
arg = PG_GETARG_DATUM(2);
}
if (val_type == InvalidOid || val_type == UNKNOWNOID) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("arg 2: could not determine data type")));
}
add_json(arg, PG_ARGISNULL(2), state, val_type, false);
PG_RETURN_POINTER(state);
}
* json_object_agg final function.
*
*/
Datum json_object_agg_finalfn(PG_FUNCTION_ARGS)
{
StringInfo state;
Assert(AggCheckCallContext(fcinfo, NULL));
state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0);
if (state == NULL) {
PG_RETURN_TEXT_P(cstring_to_text("{}"));
}
PG_RETURN_TEXT_P(catenate_stringinfo_string(state, " }"));
}
* Helper function for aggregates: return given StringInfo's contents plus
* specified trailing string, as a text datum. We need this because aggregate
* final functions are not allowed to modify the aggregate state.
*/
static text *catenate_stringinfo_string(StringInfo buffer, const char *addon)
{
int buflen = buffer->len;
int addlen = strlen(addon);
Size resbuflen = buflen + addlen;
text *result = (text *)palloc(resbuflen + VARHDRSZ);
SET_VARSIZE(result, resbuflen + VARHDRSZ);
int rc = memcpy_s(VARDATA(result), resbuflen, buffer->data, buflen);
securec_check(rc, "\0", "\0");
rc = memcpy_s(VARDATA(result) + buflen, resbuflen - buflen, addon, addlen);
securec_check(rc, "\0", "\0");
return result;
}
* SQL function json_build_object(variadic "any")
*/
Datum json_build_object(PG_FUNCTION_ARGS)
{
int nargs = PG_NARGS();
int i;
Datum arg;
char *sep = "";
StringInfo result;
Oid val_type;
if (nargs % 2 != 0) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid number or arguments: object must be matched key value pairs")));
}
result = makeStringInfo();
appendStringInfoChar(result, '{');
for (i = 0; i < nargs; i += 2) {
if (PG_ARGISNULL(i)) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("arg %d: key cannot be null", i + 1)));
}
val_type = get_fn_expr_argtype(fcinfo->flinfo, i);
* turn a constant (more or less literal) value that's of unknown type
* into text. Unknowns come in as a cstring pointer.
*/
if (val_type == UNKNOWNOID && get_fn_expr_arg_stable(fcinfo->flinfo, i)) {
val_type = TEXTOID;
if (PG_ARGISNULL(i)) {
arg = (Datum) 0;
} else {
arg = CStringGetTextDatum(PG_GETARG_POINTER(i));
}
} else {
arg = PG_GETARG_DATUM(i);
}
if (val_type == InvalidOid || val_type == UNKNOWNOID) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("arg %d: could not determine data type", i + 1)));
}
appendStringInfoString(result, sep);
sep = ", ";
add_json(arg, false, result, val_type, true);
appendStringInfoString(result, " : ");
val_type = get_fn_expr_argtype(fcinfo->flinfo, i + 1);
if (val_type == UNKNOWNOID && get_fn_expr_arg_stable(fcinfo->flinfo, i + 1)) {
val_type = TEXTOID;
if (PG_ARGISNULL(i + 1)) {
arg = (Datum) 0;
} else {
arg = CStringGetTextDatum(PG_GETARG_POINTER(i + 1));
}
} else {
arg = PG_GETARG_DATUM(i + 1);
}
if (val_type == InvalidOid || val_type == UNKNOWNOID) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("arg %d: could not determine data type", i + 2)));
}
add_json(arg, PG_ARGISNULL(i + 1), result, val_type, false);
}
appendStringInfoChar(result, '}');
PG_RETURN_TEXT_P(cstring_to_text_with_len(result->data, result->len));
}
* degenerate case of json_build_object where it gets 0 arguments.
*/
Datum json_build_object_noargs(PG_FUNCTION_ARGS)
{
PG_RETURN_TEXT_P(cstring_to_text_with_len("{}", 2));
}
* SQL function json_build_array(variadic "any")
*/
Datum json_build_array(PG_FUNCTION_ARGS)
{
int nargs = PG_NARGS();
int i;
Datum arg;
char *sep = "";
StringInfo result;
Oid val_type;
result = makeStringInfo();
appendStringInfoChar(result, '[');
for (i = 0; i < nargs; i++) {
val_type = get_fn_expr_argtype(fcinfo->flinfo, i);
if (val_type == UNKNOWNOID && get_fn_expr_arg_stable(fcinfo->flinfo, i)) {
val_type = TEXTOID;
if (PG_ARGISNULL(i)) {
arg = (Datum) 0;
} else {
arg = CStringGetTextDatum(PG_GETARG_POINTER(i));
}
} else {
arg = PG_GETARG_DATUM(i);
}
if (val_type == InvalidOid || val_type == UNKNOWNOID) {
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("arg %d: could not determine data type", i + 1)));
}
appendStringInfoString(result, sep);
sep = ", ";
add_json(arg, PG_ARGISNULL(i), result, val_type, false);
}
appendStringInfoChar(result, ']');
PG_RETURN_TEXT_P(cstring_to_text_with_len(result->data, result->len));
}
* degenerate case of json_build_array where it gets 0 arguments.
*/
Datum json_build_array_noargs(PG_FUNCTION_ARGS)
{
PG_RETURN_TEXT_P(cstring_to_text_with_len("[]", 2));
}
* SQL function json_object(text[])
*
* take a one or two dimensional array of text as name vale pairs
* for a json object.
*
*/
Datum json_object(PG_FUNCTION_ARGS)
{
if (fcinfo->nargs == 0) {
PG_RETURN_DATUM(CStringGetTextDatum("{}"));
}
ArrayType *in_array = PG_GETARG_ARRAYTYPE_P(0);
int ndims = ARR_NDIM(in_array);
StringInfoData result;
Datum *in_datums = NULL;
bool *in_nulls = NULL;
int in_count, count, i;
text *rval = NULL;
char *v = NULL;
switch (ndims) {
case 0:
PG_RETURN_DATUM(CStringGetTextDatum("{}"));
break;
case 1:
if ((ARR_DIMS(in_array)[0]) % 2)
ereport(ERROR,
(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
errmsg("array must have even number of elements")));
break;
case 2:
if ((ARR_DIMS(in_array)[1]) != 2)
ereport(ERROR,
(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
errmsg("array must have two columns")));
break;
default:
ereport(ERROR,
(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
errmsg("wrong number of array subscripts")));
}
deconstruct_array(in_array, TEXTOID, -1, false, 'i', &in_datums, &in_nulls, &in_count);
count = in_count / 2;
initStringInfo(&result);
appendStringInfoChar(&result, '{');
for (i = 0; i < count; ++i) {
if (in_nulls[i * 2]) {
ereport(ERROR,
(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
errmsg("null value not allowed for object key")));
}
v = TextDatumGetCString(in_datums[i * 2]);
if (v[0] == '\0') {
ereport(ERROR,
(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
errmsg("empty value not allowed for object key")));
}
if (i > 0) {
appendStringInfoString(&result, ", ");
}
escape_json(&result, v);
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);
}
}
appendStringInfoChar(&result, '}');
pfree(in_datums);
pfree(in_nulls);
rval = cstring_to_text_with_len(result.data, result.len);
pfree(result.data);
PG_RETURN_TEXT_P(rval);
}
* SQL function json_object(text[], text[])
*
* take separate name and value arrays of text to construct a json object
* pairwise.
*/
Datum json_object_two_arg(PG_FUNCTION_ARGS)
{
ArrayType *key_array = PG_GETARG_ARRAYTYPE_P(0);
ArrayType *val_array = PG_GETARG_ARRAYTYPE_P(1);
int nkdims = ARR_NDIM(key_array);
int nvdims = ARR_NDIM(val_array);
StringInfoData result;
Datum *key_datums = NULL;
Datum *val_datums = NULL;
bool *key_nulls = NULL;
bool *val_nulls = NULL;
int key_count, val_count, i;
text *rval = NULL;
char *v = NULL;
if (nkdims > 1 || nkdims != nvdims) {
ereport(ERROR,
(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
errmsg("wrong number of array subscripts")));
}
if (nkdims == 0) {
PG_RETURN_DATUM(CStringGetTextDatum("{}"));
}
deconstruct_array(key_array, TEXTOID, -1, false, 'i', &key_datums, &key_nulls, &key_count);
deconstruct_array(val_array, TEXTOID, -1, false, 'i', &val_datums, &val_nulls, &val_count);
if (key_count != val_count) {
ereport(ERROR,
(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
errmsg("mismatched array dimensions")));
}
initStringInfo(&result);
appendStringInfoChar(&result, '{');
for (i = 0; i < key_count; ++i) {
if (key_nulls[i]) {
ereport(ERROR,
(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
errmsg("null value not allowed for object key")));
}
v = TextDatumGetCString(key_datums[i]);
if (v[0] == '\0') {
ereport(ERROR,
(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
errmsg("empty value not allowed for object key")));
}
if (i > 0) {
appendStringInfoString(&result, ", ");
}
escape_json(&result, v);
appendStringInfoString(&result, " : ");
pfree(v);
if (val_nulls[i]) {
appendStringInfoString(&result, "null");
} else {
v = TextDatumGetCString(val_datums[i]);
escape_json(&result, v);
pfree(v);
}
}
appendStringInfoChar(&result, '}');
pfree(key_datums);
pfree(key_nulls);
pfree(val_datums);
pfree(val_nulls);
rval = cstring_to_text_with_len(result.data, result.len);
pfree(result.data);
PG_RETURN_TEXT_P(rval);
}
* Produce a JSON string literal, properly escaping characters in the text.
*/
void escape_json(StringInfo buf, const char *str)
{
const char *p = NULL;
int charlen = 0;
appendStringInfoCharMacro(buf, '\"');
p = str;
while (*p != '\0') {
charlen = pg_mblen(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 {
for (int i = 0; i < charlen; i++) {
appendStringInfoCharMacro(buf, *(p + i));
}
}
break;
}
p += charlen;
}
appendStringInfoCharMacro(buf, '\"');
}
* SQL function json_typeof(json) -> text
*
* Returns the type of the outermost JSON value as TEXT. Possible types are
* "object", "array", "string", "number", "boolean", and "null".
*
* Performs a single call to json_lex() to get the first token of the supplied
* value. This initial token uniquely determines the value's type. As our
* input must already have been validated by json_in() or json_recv(), the
* initial token should never be JSON_TOKEN_OBJECT_END, JSON_TOKEN_ARRAY_END,
* JSON_TOKEN_COLON, JSON_TOKEN_COMMA, or JSON_TOKEN_END.
*/
Datum json_typeof(PG_FUNCTION_ARGS)
{
text *json = NULL;
JsonLexContext *lex = NULL;
JsonTokenType tok;
char *type = NULL;
json = PG_GETARG_TEXT_P(0);
lex = makeJsonLexContext(json, false);
json_lex(lex);
tok = lex_peek(lex);
switch (tok) {
case JSON_TOKEN_OBJECT_START:
type = "object";
break;
case JSON_TOKEN_ARRAY_START:
type = "array";
break;
case JSON_TOKEN_STRING:
type = "string";
break;
case JSON_TOKEN_NUMBER:
type = "number";
break;
case JSON_TOKEN_TRUE:
case JSON_TOKEN_FALSE:
type = "boolean";
break;
case JSON_TOKEN_NULL:
type = "null";
break;
default:
elog(ERROR, "unexpected json token: %d", tok);
}
PG_RETURN_TEXT_P(cstring_to_text(type));
}
extern int json_typeof_internal(text* json)
{
JsonLexContext *lex = makeJsonLexContext(json, false);
json_lex(lex);
return lex_peek(lex);
}