From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ewan Young <kdbase.hack@gmail.com>
cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        Michael Paquier <michael@paquier.xyz>
Subject: Re: Use ereport() instead of elog() for invalid weights in
 setweight()
In-reply-to: 
 <CAON2xHNaeLAUzRCXL5AmXLcXaSE_gWAVjWQRmLzc_oZ=1_Vf4Q@mail.gmail.com>
References: 
 <CAON2xHNaeLAUzRCXL5AmXLcXaSE_gWAVjWQRmLzc_oZ=1_Vf4Q@mail.gmail.com>
Comments: In-reply-to Ewan Young <kdbase.hack@gmail.com>
	message dated "Wed, 03 Jun 2026 23:39:05 +0800"
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Date: Wed, 03 Jun 2026 14:17:53 -0400
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Ewan Young <kdbase.hack@gmail.com> writes:
> I noticed that setweight() reports an internal error (SQLSTATE XX000)
> when the weight argument is not one of A/a, B/b, C/c, D/d, even though
> the weight comes directly from user input.  The two-argument variant
> also prints the weight as a raw ASCII code, which is a bit unfriendly:

>     =# SELECT setweight('cat:1'::tsvector, 'p');
>     ERROR:  unrecognized weight: 112

I agree that these ought to be ereport()s.  However, I suspect that
the reason for printing bogus weights numerically was to avoid the
risk of generating encoding-incorrect strings if the given char
value has its high bit set.  The existing code in tsvector_filter
is failing to consider that hazard.

I experimented with making the error messages print non-ASCII
characters differently, and soon decided that that added enough
complexity that we shouldn't have three copies of it.  So the
attached proposed v2 also factors the code out into a new
function parse_weight (maybe a different name would be better?).

I'm unconvinced that we really need a regression test case for
this ...

			regards, tom lane


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Content-Type: text/x-diff;
	name*0="v2-0001-Use-ereport-not-elog-for-invalid-weights-in-setweig";
	name*1="ht.patch"; charset="us-ascii"
Content-ID: <3096030.1780510651.2@sss.pgh.pa.us>
Content-Description: 
 v2-0001-Use-ereport-not-elog-for-invalid-weights-in-setweight.patch
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diff --git a/src/backend/utils/adt/tsvector_op.c b/src/backend/utils/adt/t=
svector_op.c
index d8dece42b9b..53a9541e89f 100644
--- a/src/backend/utils/adt/tsvector_op.c
+++ b/src/backend/utils/adt/tsvector_op.c
@@ -207,17 +207,10 @@ tsvector_length(PG_FUNCTION_ARGS)
 	PG_RETURN_INT32(ret);
 }
 =

-Datum
-tsvector_setweight(PG_FUNCTION_ARGS)
+static int
+parse_weight(char cw)
 {
-	TSVector	in =3D PG_GETARG_TSVECTOR(0);
-	char		cw =3D PG_GETARG_CHAR(1);
-	TSVector	out;
-	int			i,
-				j;
-	WordEntry  *entry;
-	WordEntryPos *p;
-	int			w =3D 0;
+	int			w;
 =

 	switch (cw)
 	{
@@ -238,9 +231,32 @@ tsvector_setweight(PG_FUNCTION_ARGS)
 			w =3D 0;
 			break;
 		default:
-			/* internal error */
-			elog(ERROR, "unrecognized weight: %d", cw);
+			/* Avoid printing non-ASCII bytes, else we have encoding issues */
+			if (cw >=3D ' ' && cw < 0x7f)
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("unrecognized weight: \"%c\"", cw)));
+			else				/* use \ooo format, like charout() */
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("unrecognized weight: \"\\%03o\"",
+								(unsigned char) cw)));
 	}
+	return w;
+}
+
+
+Datum
+tsvector_setweight(PG_FUNCTION_ARGS)
+{
+	TSVector	in =3D PG_GETARG_TSVECTOR(0);
+	char		cw =3D PG_GETARG_CHAR(1);
+	TSVector	out;
+	int			i,
+				j;
+	WordEntry  *entry;
+	WordEntryPos *p;
+	int			w =3D parse_weight(cw);
 =

 	out =3D (TSVector) palloc(VARSIZE(in));
 	memcpy(out, in, VARSIZE(in));
@@ -285,28 +301,7 @@ tsvector_setweight_by_filter(PG_FUNCTION_ARGS)
 	Datum	   *dlexemes;
 	bool	   *nulls;
 =

-	switch (char_weight)
-	{
-		case 'A':
-		case 'a':
-			weight =3D 3;
-			break;
-		case 'B':
-		case 'b':
-			weight =3D 2;
-			break;
-		case 'C':
-		case 'c':
-			weight =3D 1;
-			break;
-		case 'D':
-		case 'd':
-			weight =3D 0;
-			break;
-		default:
-			/* internal error */
-			elog(ERROR, "unrecognized weight: %c", char_weight);
-	}
+	weight =3D parse_weight(char_weight);
 =

 	tsout =3D (TSVector) palloc(VARSIZE(tsin));
 	memcpy(tsout, tsin, VARSIZE(tsin));
@@ -846,29 +841,7 @@ tsvector_filter(PG_FUNCTION_ARGS)
 					 errmsg("weight array may not contain nulls")));
 =

 		char_weight =3D DatumGetChar(dweights[i]);
-		switch (char_weight)
-		{
-			case 'A':
-			case 'a':
-				mask =3D mask | 8;
-				break;
-			case 'B':
-			case 'b':
-				mask =3D mask | 4;
-				break;
-			case 'C':
-			case 'c':
-				mask =3D mask | 2;
-				break;
-			case 'D':
-			case 'd':
-				mask =3D mask | 1;
-				break;
-			default:
-				ereport(ERROR,
-						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-						 errmsg("unrecognized weight: \"%c\"", char_weight)));
-		}
+		mask |=3D 1 << parse_weight(char_weight);
 	}
 =

 	tsout =3D (TSVector) palloc0(VARSIZE(tsin));

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