Prevent infinity and NaN in jsonb/plperl transform

jsonb uses numeric internally, and numeric can store NaN, but that is
not allowed by jsonb on input, so we shouldn't store it.  Also prevent
infinity to get a consistent error message.  (numeric input would reject
infinity anyway.)
Reported-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>

contrib/jsonb_plperl/expected/jsonb_plperl.out

@@ -39,6 +39,26 @@ SELECT testSVToJsonb();
  1
 (1 row)
 
+CREATE FUNCTION testInf() RETURNS jsonb
+LANGUAGE plperl
+TRANSFORM FOR TYPE jsonb
+AS $$
+$val = 0 + 'Inf';
+return $val;
+$$;
+SELECT testInf();
+ERROR:  cannot convert infinity to jsonb
+CONTEXT:  PL/Perl function "testinf"
+CREATE FUNCTION testNaN() RETURNS jsonb
+LANGUAGE plperl
+TRANSFORM FOR TYPE jsonb
+AS $$
+$val = 0 + 'NaN';
+return $val;
+$$;
+SELECT testNaN();
+ERROR:  cannot convert NaN to jsonb
+CONTEXT:  PL/Perl function "testnan"
 -- this revealed a bug in the original implementation
 CREATE FUNCTION testRegexpResultToJsonb() RETURNS jsonb
 LANGUAGE plperl
@@ -71,7 +91,7 @@ SELECT roundtrip('1');
 (1 row)
 
 SELECT roundtrip('1E+131071');
-ERROR:  cannot convert infinite value to jsonb
+ERROR:  cannot convert infinity to jsonb
 CONTEXT:  PL/Perl function "roundtrip"
 SELECT roundtrip('-1');
  roundtrip 
@@ -207,4 +227,4 @@ SELECT roundtrip('{"1": {"2": [3, 4, 5]}, "2": 3}');
 
 \set VERBOSITY terse \\ -- suppress cascade details
 DROP EXTENSION plperl CASCADE;
-NOTICE:  drop cascades to 6 other objects
+NOTICE:  drop cascades to 8 other objects

contrib/jsonb_plperl/expected/jsonb_plperlu.out

@@ -39,6 +39,26 @@ SELECT testSVToJsonb();
  1
 (1 row)
 
+CREATE FUNCTION testInf() RETURNS jsonb
+LANGUAGE plperlu
+TRANSFORM FOR TYPE jsonb
+AS $$
+$val = 0 + 'Inf';
+return $val;
+$$;
+SELECT testInf();
+ERROR:  cannot convert infinity to jsonb
+CONTEXT:  PL/Perl function "testinf"
+CREATE FUNCTION testNaN() RETURNS jsonb
+LANGUAGE plperlu
+TRANSFORM FOR TYPE jsonb
+AS $$
+$val = 0 + 'NaN';
+return $val;
+$$;
+SELECT testNaN();
+ERROR:  cannot convert NaN to jsonb
+CONTEXT:  PL/Perl function "testnan"
 -- this revealed a bug in the original implementation
 CREATE FUNCTION testRegexpResultToJsonb() RETURNS jsonb
 LANGUAGE plperlu
@@ -71,7 +91,7 @@ SELECT roundtrip('1');
 (1 row)
 
 SELECT roundtrip('1E+131071');
-ERROR:  cannot convert infinite value to jsonb
+ERROR:  cannot convert infinity to jsonb
 CONTEXT:  PL/Perl function "roundtrip"
 SELECT roundtrip('-1');
  roundtrip 
@@ -207,4 +227,4 @@ SELECT roundtrip('{"1": {"2": [3, 4, 5]}, "2": 3}');
 
 \set VERBOSITY terse \\ -- suppress cascade details
 DROP EXTENSION plperlu CASCADE;
-NOTICE:  drop cascades to 6 other objects
+NOTICE:  drop cascades to 8 other objects

contrib/jsonb_plperl/jsonb_plperl.c

@@ -211,10 +211,22 @@ SV_to_JsonbValue(SV *in, JsonbParseState **jsonb_state, bool is_elem)
 			{
 				double		nval = SvNV(in);
 
+				/*
+				 * jsonb doesn't allow infinity or NaN (per JSON
+				 * specification), but the numeric type that is used for the
+				 * storage accepts NaN, so we have to prevent it here
+				 * explicitly.  We don't really have to check for isinf()
+				 * here, as numeric doesn't allow it and it would be caught
+				 * later, but it makes for a nicer error message.
+				 */
 				if (isinf(nval))
 					ereport(ERROR,
-							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-							 (errmsg("cannot convert infinite value to jsonb"))));
+							(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+							 (errmsg("cannot convert infinity to jsonb"))));
+				if (isnan(nval))
+					ereport(ERROR,
+							(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+							 (errmsg("cannot convert NaN to jsonb"))));
 
 				out.type = jbvNumeric;
 				out.val.numeric =

contrib/jsonb_plperl/sql/jsonb_plperl.sql

@@ -34,6 +34,28 @@ $$;
 SELECT testSVToJsonb();
 
 
+CREATE FUNCTION testInf() RETURNS jsonb
+LANGUAGE plperl
+TRANSFORM FOR TYPE jsonb
+AS $$
+$val = 0 + 'Inf';
+return $val;
+$$;
+
+SELECT testInf();
+
+
+CREATE FUNCTION testNaN() RETURNS jsonb
+LANGUAGE plperl
+TRANSFORM FOR TYPE jsonb
+AS $$
+$val = 0 + 'NaN';
+return $val;
+$$;
+
+SELECT testNaN();
+
+
 -- this revealed a bug in the original implementation
 CREATE FUNCTION testRegexpResultToJsonb() RETURNS jsonb
 LANGUAGE plperl

contrib/jsonb_plperl/sql/jsonb_plperlu.sql

@@ -34,6 +34,28 @@ $$;
 SELECT testSVToJsonb();
 
 
+CREATE FUNCTION testInf() RETURNS jsonb
+LANGUAGE plperlu
+TRANSFORM FOR TYPE jsonb
+AS $$
+$val = 0 + 'Inf';
+return $val;
+$$;
+
+SELECT testInf();
+
+
+CREATE FUNCTION testNaN() RETURNS jsonb
+LANGUAGE plperlu
+TRANSFORM FOR TYPE jsonb
+AS $$
+$val = 0 + 'NaN';
+return $val;
+$$;
+
+SELECT testNaN();
+
+
 -- this revealed a bug in the original implementation
 CREATE FUNCTION testRegexpResultToJsonb() RETURNS jsonb
 LANGUAGE plperlu