Replace argument-checking Asserts with regular test-and-elog checks in all

encoding conversion functions.  These are not can't-happen cases because
it's possible to create a conversion with the wrong conversion function
for the specified encoding pair.  That would lead to an Assert crash in
an Assert-enabled build, or incorrect conversion otherwise, neither of
which is desirable.  This would be a DOS issue if production databases
were customarily built with asserts enabled, but fortunately that's not so.
Per an observation by Heikki.

Back-patch to all supported branches.

28 files changed, 166 insertions, 282 deletions

diff --git a/src/backend/utils/mb/conversion_procs/ascii_and_mic/ascii_and_mic.c b/src/backend/utils/mb/conversion_procs/ascii_and_mic/ascii_and_mic.c
index 7bddc9ee603..afd09e0171d 100644
--- a/src/backend/utils/mb/conversion_procs/ascii_and_mic/ascii_and_mic.c
+++ b/src/backend/utils/mb/conversion_procs/ascii_and_mic/ascii_and_mic.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/ascii_and_mic/ascii_and_mic.c,v 1.15 2009/01/01 17:23:51 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/ascii_and_mic/ascii_and_mic.c,v 1.16 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -41,9 +41,7 @@ ascii_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_SQL_ASCII);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_SQL_ASCII, PG_MULE_INTERNAL);
 
 	pg_ascii2mic(src, dest, len);
 
@@ -57,9 +55,7 @@ mic_to_ascii(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_SQL_ASCII);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_SQL_ASCII);
 
 	pg_mic2ascii(src, dest, len);
 
diff --git a/src/backend/utils/mb/conversion_procs/cyrillic_and_mic/cyrillic_and_mic.c b/src/backend/utils/mb/conversion_procs/cyrillic_and_mic/cyrillic_and_mic.c
index 551921daa4d..dd2804d5ddc 100644
--- a/src/backend/utils/mb/conversion_procs/cyrillic_and_mic/cyrillic_and_mic.c
+++ b/src/backend/utils/mb/conversion_procs/cyrillic_and_mic/cyrillic_and_mic.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/cyrillic_and_mic/cyrillic_and_mic.c,v 1.18 2009/01/01 17:23:51 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/cyrillic_and_mic/cyrillic_and_mic.c,v 1.19 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -88,9 +88,7 @@ koi8r_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_KOI8R);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_KOI8R, PG_MULE_INTERNAL);
 
 	koi8r2mic(src, dest, len);
 
@@ -104,9 +102,7 @@ mic_to_koi8r(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_KOI8R);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_KOI8R);
 
 	mic2koi8r(src, dest, len);
 
@@ -120,9 +116,7 @@ iso_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_ISO_8859_5);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_ISO_8859_5, PG_MULE_INTERNAL);
 
 	iso2mic(src, dest, len);
 
@@ -136,9 +130,7 @@ mic_to_iso(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_ISO_8859_5);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_ISO_8859_5);
 
 	mic2iso(src, dest, len);
 
@@ -152,9 +144,7 @@ win1251_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN1251);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN1251, PG_MULE_INTERNAL);
 
 	win12512mic(src, dest, len);
 
@@ -168,9 +158,7 @@ mic_to_win1251(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_WIN1251);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_WIN1251);
 
 	mic2win1251(src, dest, len);
 
@@ -184,9 +172,7 @@ win866_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN866);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN866, PG_MULE_INTERNAL);
 
 	win8662mic(src, dest, len);
 
@@ -200,9 +186,7 @@ mic_to_win866(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_WIN866);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_WIN866);
 
 	mic2win866(src, dest, len);
 
@@ -217,9 +201,7 @@ koi8r_to_win1251(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_KOI8R);
-	Assert(PG_GETARG_INT32(1) == PG_WIN1251);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_KOI8R, PG_WIN1251);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	koi8r2mic(src, buf, len);
@@ -237,9 +219,7 @@ win1251_to_koi8r(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN1251);
-	Assert(PG_GETARG_INT32(1) == PG_KOI8R);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN1251, PG_KOI8R);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	win12512mic(src, buf, len);
@@ -257,9 +237,7 @@ koi8r_to_win866(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_KOI8R);
-	Assert(PG_GETARG_INT32(1) == PG_WIN866);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_KOI8R, PG_WIN866);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	koi8r2mic(src, buf, len);
@@ -277,9 +255,7 @@ win866_to_koi8r(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN866);
-	Assert(PG_GETARG_INT32(1) == PG_KOI8R);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN866, PG_KOI8R);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	win8662mic(src, buf, len);
@@ -297,9 +273,7 @@ win866_to_win1251(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN866);
-	Assert(PG_GETARG_INT32(1) == PG_WIN1251);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN866, PG_WIN1251);
 
 	/*
 	 * Note: There are a few characters like the "Numero" sign that exist in
@@ -323,9 +297,7 @@ win1251_to_win866(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN1251);
-	Assert(PG_GETARG_INT32(1) == PG_WIN866);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN1251, PG_WIN866);
 
 	/* Use mic/KOI8R as intermediary, see comment in win866_to_win1251() */
 	buf = palloc(len * ENCODING_GROWTH_RATE);
@@ -344,9 +316,7 @@ iso_to_koi8r(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_ISO_8859_5);
-	Assert(PG_GETARG_INT32(1) == PG_KOI8R);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_ISO_8859_5, PG_KOI8R);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	iso2mic(src, buf, len);
@@ -364,9 +334,7 @@ koi8r_to_iso(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_KOI8R);
-	Assert(PG_GETARG_INT32(1) == PG_ISO_8859_5);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_KOI8R, PG_ISO_8859_5);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	koi8r2mic(src, buf, len);
@@ -384,9 +352,7 @@ iso_to_win1251(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_ISO_8859_5);
-	Assert(PG_GETARG_INT32(1) == PG_WIN1251);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_ISO_8859_5, PG_WIN1251);
 
 	/* Use mic/KOI8R as intermediary, see comment in win866_to_win1251() */
 	buf = palloc(len * ENCODING_GROWTH_RATE);
@@ -405,9 +371,7 @@ win1251_to_iso(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN1251);
-	Assert(PG_GETARG_INT32(1) == PG_ISO_8859_5);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN1251, PG_ISO_8859_5);
 
 	/* Use mic/KOI8R as intermediary, see comment in win866_to_win1251() */
 	buf = palloc(len * ENCODING_GROWTH_RATE);
@@ -426,9 +390,7 @@ iso_to_win866(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_ISO_8859_5);
-	Assert(PG_GETARG_INT32(1) == PG_WIN866);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_ISO_8859_5, PG_WIN866);
 
 	/* Use mic/KOI8R as intermediary, see comment in win866_to_win1251() */
 	buf = palloc(len * ENCODING_GROWTH_RATE);
@@ -447,9 +409,7 @@ win866_to_iso(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN866);
-	Assert(PG_GETARG_INT32(1) == PG_ISO_8859_5);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN866, PG_ISO_8859_5);
 
 	/* Use mic/KOI8R as intermediary, see comment in win866_to_win1251() */
 	buf = palloc(len * ENCODING_GROWTH_RATE);
diff --git a/src/backend/utils/mb/conversion_procs/euc_cn_and_mic/euc_cn_and_mic.c b/src/backend/utils/mb/conversion_procs/euc_cn_and_mic/euc_cn_and_mic.c
index 5921e8ab256..c9dd40407e2 100644
--- a/src/backend/utils/mb/conversion_procs/euc_cn_and_mic/euc_cn_and_mic.c
+++ b/src/backend/utils/mb/conversion_procs/euc_cn_and_mic/euc_cn_and_mic.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_cn_and_mic/euc_cn_and_mic.c,v 1.18 2009/01/01 17:23:51 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_cn_and_mic/euc_cn_and_mic.c,v 1.19 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -44,9 +44,7 @@ euc_cn_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_CN);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_CN, PG_MULE_INTERNAL);
 
 	euc_cn2mic(src, dest, len);
 
@@ -60,9 +58,7 @@ mic_to_euc_cn(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_CN);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_EUC_CN);
 
 	mic2euc_cn(src, dest, len);
 
diff --git a/src/backend/utils/mb/conversion_procs/euc_jis_2004_and_shift_jis_2004/euc_jis_2004_and_shift_jis_2004.c b/src/backend/utils/mb/conversion_procs/euc_jis_2004_and_shift_jis_2004/euc_jis_2004_and_shift_jis_2004.c
index ba10a56cdb8..e65d755368f 100644
--- a/src/backend/utils/mb/conversion_procs/euc_jis_2004_and_shift_jis_2004/euc_jis_2004_and_shift_jis_2004.c
+++ b/src/backend/utils/mb/conversion_procs/euc_jis_2004_and_shift_jis_2004/euc_jis_2004_and_shift_jis_2004.c
@@ -5,7 +5,7 @@
  * Copyright (c) 2007-2009, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_jis_2004_and_shift_jis_2004/euc_jis_2004_and_shift_jis_2004.c,v 1.5 2009/01/01 17:23:51 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_jis_2004_and_shift_jis_2004/euc_jis_2004_and_shift_jis_2004.c,v 1.6 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -43,9 +43,7 @@ euc_jis_2004_to_shift_jis_2004(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_JIS_2004);
-	Assert(PG_GETARG_INT32(1) == PG_SHIFT_JIS_2004);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_JIS_2004, PG_SHIFT_JIS_2004);
 
 	euc_jis_20042shift_jis_2004(src, dest, len);
 
@@ -59,9 +57,7 @@ shift_jis_2004_to_euc_jis_2004(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_SHIFT_JIS_2004);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_JIS_2004);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_SHIFT_JIS_2004, PG_EUC_JIS_2004);
 
 	shift_jis_20042euc_jis_2004(src, dest, len);
 
diff --git a/src/backend/utils/mb/conversion_procs/euc_jp_and_sjis/euc_jp_and_sjis.c b/src/backend/utils/mb/conversion_procs/euc_jp_and_sjis/euc_jp_and_sjis.c
index 985d00b0d0c..4ad71328ff6 100644
--- a/src/backend/utils/mb/conversion_procs/euc_jp_and_sjis/euc_jp_and_sjis.c
+++ b/src/backend/utils/mb/conversion_procs/euc_jp_and_sjis/euc_jp_and_sjis.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_jp_and_sjis/euc_jp_and_sjis.c,v 1.20 2009/01/01 17:23:51 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_jp_and_sjis/euc_jp_and_sjis.c,v 1.21 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -70,9 +70,7 @@ euc_jp_to_sjis(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_JP);
-	Assert(PG_GETARG_INT32(1) == PG_SJIS);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_JP, PG_SJIS);
 
 	euc_jp2sjis(src, dest, len);
 
@@ -86,9 +84,7 @@ sjis_to_euc_jp(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_SJIS);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_JP);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_SJIS, PG_EUC_JP);
 
 	sjis2euc_jp(src, dest, len);
 
@@ -102,9 +98,7 @@ euc_jp_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_JP);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_JP, PG_MULE_INTERNAL);
 
 	euc_jp2mic(src, dest, len);
 
@@ -118,9 +112,7 @@ mic_to_euc_jp(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_JP);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_EUC_JP);
 
 	mic2euc_jp(src, dest, len);
 
@@ -134,9 +126,7 @@ sjis_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_SJIS);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_SJIS, PG_MULE_INTERNAL);
 
 	sjis2mic(src, dest, len);
 
@@ -150,9 +140,7 @@ mic_to_sjis(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_SJIS);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_SJIS);
 
 	mic2sjis(src, dest, len);
 
diff --git a/src/backend/utils/mb/conversion_procs/euc_kr_and_mic/euc_kr_and_mic.c b/src/backend/utils/mb/conversion_procs/euc_kr_and_mic/euc_kr_and_mic.c
index 1d14ef6b316..878ab9d603a 100644
--- a/src/backend/utils/mb/conversion_procs/euc_kr_and_mic/euc_kr_and_mic.c
+++ b/src/backend/utils/mb/conversion_procs/euc_kr_and_mic/euc_kr_and_mic.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_kr_and_mic/euc_kr_and_mic.c,v 1.18 2009/01/01 17:23:51 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_kr_and_mic/euc_kr_and_mic.c,v 1.19 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -44,9 +44,7 @@ euc_kr_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_KR);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_KR, PG_MULE_INTERNAL);
 
 	euc_kr2mic(src, dest, len);
 
@@ -60,9 +58,7 @@ mic_to_euc_kr(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_KR);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_EUC_KR);
 
 	mic2euc_kr(src, dest, len);
 
diff --git a/src/backend/utils/mb/conversion_procs/euc_tw_and_big5/euc_tw_and_big5.c b/src/backend/utils/mb/conversion_procs/euc_tw_and_big5/euc_tw_and_big5.c
index 3bc6e1d6df8..474432571c1 100644
--- a/src/backend/utils/mb/conversion_procs/euc_tw_and_big5/euc_tw_and_big5.c
+++ b/src/backend/utils/mb/conversion_procs/euc_tw_and_big5/euc_tw_and_big5.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_tw_and_big5/euc_tw_and_big5.c,v 1.19 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/euc_tw_and_big5/euc_tw_and_big5.c,v 1.20 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -57,9 +57,7 @@ euc_tw_to_big5(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_TW);
-	Assert(PG_GETARG_INT32(1) == PG_BIG5);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_TW, PG_BIG5);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	euc_tw2mic(src, buf, len);
@@ -77,9 +75,7 @@ big5_to_euc_tw(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_BIG5);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_TW);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_BIG5, PG_EUC_TW);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	big52mic(src, buf, len);
@@ -96,9 +92,7 @@ euc_tw_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_TW);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_TW, PG_MULE_INTERNAL);
 
 	euc_tw2mic(src, dest, len);
 
@@ -112,9 +106,7 @@ mic_to_euc_tw(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_TW);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_EUC_TW);
 
 	mic2euc_tw(src, dest, len);
 
@@ -128,9 +120,7 @@ big5_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_BIG5);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_BIG5, PG_MULE_INTERNAL);
 
 	big52mic(src, dest, len);
 
@@ -144,9 +134,7 @@ mic_to_big5(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_BIG5);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_BIG5);
 
 	mic2big5(src, dest, len);
 
diff --git a/src/backend/utils/mb/conversion_procs/latin2_and_win1250/latin2_and_win1250.c b/src/backend/utils/mb/conversion_procs/latin2_and_win1250/latin2_and_win1250.c
index e30fe23c0bf..0d7d8a9375a 100644
--- a/src/backend/utils/mb/conversion_procs/latin2_and_win1250/latin2_and_win1250.c
+++ b/src/backend/utils/mb/conversion_procs/latin2_and_win1250/latin2_and_win1250.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/latin2_and_win1250/latin2_and_win1250.c,v 1.16 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/latin2_and_win1250/latin2_and_win1250.c,v 1.17 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -56,9 +56,7 @@ latin2_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_LATIN2);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_LATIN2, PG_MULE_INTERNAL);
 
 	latin22mic(src, dest, len);
 
@@ -72,9 +70,7 @@ mic_to_latin2(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_LATIN2);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_LATIN2);
 
 	mic2latin2(src, dest, len);
 
@@ -88,9 +84,7 @@ win1250_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN1250);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN1250, PG_MULE_INTERNAL);
 
 	win12502mic(src, dest, len);
 
@@ -104,9 +98,7 @@ mic_to_win1250(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_WIN1250);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_WIN1250);
 
 	mic2win1250(src, dest, len);
 
@@ -121,9 +113,7 @@ latin2_to_win1250(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_LATIN2);
-	Assert(PG_GETARG_INT32(1) == PG_WIN1250);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_LATIN2, PG_WIN1250);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	latin22mic(src, buf, len);
@@ -141,9 +131,7 @@ win1250_to_latin2(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned char *buf;
 
-	Assert(PG_GETARG_INT32(0) == PG_WIN1250);
-	Assert(PG_GETARG_INT32(1) == PG_LATIN2);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_WIN1250, PG_LATIN2);
 
 	buf = palloc(len * ENCODING_GROWTH_RATE);
 	win12502mic(src, buf, len);
diff --git a/src/backend/utils/mb/conversion_procs/latin_and_mic/latin_and_mic.c b/src/backend/utils/mb/conversion_procs/latin_and_mic/latin_and_mic.c
index ccf479ea3d3..251d8b4f2eb 100644
--- a/src/backend/utils/mb/conversion_procs/latin_and_mic/latin_and_mic.c
+++ b/src/backend/utils/mb/conversion_procs/latin_and_mic/latin_and_mic.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/latin_and_mic/latin_and_mic.c,v 1.16 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/latin_and_mic/latin_and_mic.c,v 1.17 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -56,9 +56,7 @@ latin1_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_LATIN1);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_LATIN1, PG_MULE_INTERNAL);
 
 	latin12mic(src, dest, len);
 
@@ -72,9 +70,7 @@ mic_to_latin1(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_LATIN1);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_LATIN1);
 
 	mic2latin1(src, dest, len);
 
@@ -88,9 +84,7 @@ latin3_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_LATIN3);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_LATIN3, PG_MULE_INTERNAL);
 
 	latin32mic(src, dest, len);
 
@@ -104,9 +98,7 @@ mic_to_latin3(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_LATIN3);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_LATIN3);
 
 	mic2latin3(src, dest, len);
 
@@ -120,9 +112,7 @@ latin4_to_mic(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_LATIN4);
-	Assert(PG_GETARG_INT32(1) == PG_MULE_INTERNAL);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_LATIN4, PG_MULE_INTERNAL);
 
 	latin42mic(src, dest, len);
 
@@ -136,9 +126,7 @@ mic_to_latin4(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_MULE_INTERNAL);
-	Assert(PG_GETARG_INT32(1) == PG_LATIN4);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_MULE_INTERNAL, PG_LATIN4);
 
 	mic2latin4(src, dest, len);
 
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_ascii/utf8_and_ascii.c b/src/backend/utils/mb/conversion_procs/utf8_and_ascii/utf8_and_ascii.c
index 643152bfc2e..783fa2a3de6 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_ascii/utf8_and_ascii.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_ascii/utf8_and_ascii.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_ascii/utf8_and_ascii.c,v 1.17 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_ascii/utf8_and_ascii.c,v 1.18 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -41,9 +41,7 @@ ascii_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_SQL_ASCII);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_SQL_ASCII, PG_UTF8);
 
 	/* this looks wrong, but basically we're just rejecting high-bit-set */
 	pg_ascii2mic(src, dest, len);
@@ -58,9 +56,7 @@ utf8_to_ascii(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_SQL_ASCII);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_SQL_ASCII);
 
 	/* this looks wrong, but basically we're just rejecting high-bit-set */
 	pg_mic2ascii(src, dest, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_big5/utf8_and_big5.c b/src/backend/utils/mb/conversion_procs/utf8_and_big5/utf8_and_big5.c
index 6b115da92f6..5d8b27967a0 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_big5/utf8_and_big5.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_big5/utf8_and_big5.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_big5/utf8_and_big5.c,v 1.19 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_big5/utf8_and_big5.c,v 1.20 2009/01/29 19:23:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ big5_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_BIG5);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_BIG5, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapBIG5, NULL,
 			   sizeof(LUmapBIG5) / sizeof(pg_local_to_utf), 0, PG_BIG5, len);
@@ -59,9 +57,7 @@ utf8_to_big5(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_BIG5);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_BIG5);
 
 	UtfToLocal(src, dest, ULmapBIG5, NULL,
 			   sizeof(ULmapBIG5) / sizeof(pg_utf_to_local), 0, PG_BIG5, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_cyrillic/utf8_and_cyrillic.c b/src/backend/utils/mb/conversion_procs/utf8_and_cyrillic/utf8_and_cyrillic.c
index f42e8f128f4..0f22256a43f 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_cyrillic/utf8_and_cyrillic.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_cyrillic/utf8_and_cyrillic.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_cyrillic/utf8_and_cyrillic.c,v 1.22 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_cyrillic/utf8_and_cyrillic.c,v 1.23 2009/01/29 19:23:40 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -43,9 +43,7 @@ utf8_to_koi8r(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_KOI8R);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_KOI8R);
 
 	UtfToLocal(src, dest, ULmapKOI8R, NULL,
 			 sizeof(ULmapKOI8R) / sizeof(pg_utf_to_local), 0, PG_KOI8R, len);
@@ -60,9 +58,7 @@ koi8r_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_KOI8R);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_KOI8R, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapKOI8R, NULL,
 			 sizeof(LUmapKOI8R) / sizeof(pg_local_to_utf), 0, PG_KOI8R, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_euc_cn/utf8_and_euc_cn.c b/src/backend/utils/mb/conversion_procs/utf8_and_euc_cn/utf8_and_euc_cn.c
index 8e07d0ed640..92f76e3cd99 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_euc_cn/utf8_and_euc_cn.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_euc_cn/utf8_and_euc_cn.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_cn/utf8_and_euc_cn.c,v 1.20 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_cn/utf8_and_euc_cn.c,v 1.21 2009/01/29 19:23:40 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ euc_cn_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_CN);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_CN, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapEUC_CN, NULL,
 		   sizeof(LUmapEUC_CN) / sizeof(pg_local_to_utf), 0, PG_EUC_CN, len);
@@ -59,9 +57,7 @@ utf8_to_euc_cn(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_CN);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_EUC_CN);
 
 	UtfToLocal(src, dest, ULmapEUC_CN, NULL,
 		   sizeof(ULmapEUC_CN) / sizeof(pg_utf_to_local), 0, PG_EUC_CN, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_euc_jis_2004/utf8_and_euc_jis_2004.c b/src/backend/utils/mb/conversion_procs/utf8_and_euc_jis_2004/utf8_and_euc_jis_2004.c
index c44b2f3d8bb..efc01536320 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_euc_jis_2004/utf8_and_euc_jis_2004.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_euc_jis_2004/utf8_and_euc_jis_2004.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_jis_2004/utf8_and_euc_jis_2004.c,v 1.4 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_jis_2004/utf8_and_euc_jis_2004.c,v 1.5 2009/01/29 19:23:40 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -44,9 +44,7 @@ euc_jis_2004_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_JIS_2004);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_JIS_2004, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapEUC_JIS_2004, LUmapEUC_JIS_2004_combined,
 			   sizeof(LUmapEUC_JIS_2004) / sizeof(pg_local_to_utf),
@@ -63,9 +61,7 @@ utf8_to_euc_jis_2004(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_JIS_2004);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_EUC_JIS_2004);
 
 	UtfToLocal(src, dest, ULmapEUC_JIS_2004, ULmapEUC_JIS_2004_combined,
 			   sizeof(ULmapEUC_JIS_2004) / sizeof(pg_utf_to_local),
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_euc_jp/utf8_and_euc_jp.c b/src/backend/utils/mb/conversion_procs/utf8_and_euc_jp/utf8_and_euc_jp.c
index 83abf81b386..d84a19bc22f 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_euc_jp/utf8_and_euc_jp.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_euc_jp/utf8_and_euc_jp.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_jp/utf8_and_euc_jp.c,v 1.20 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_jp/utf8_and_euc_jp.c,v 1.21 2009/01/29 19:23:40 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ euc_jp_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_JP);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_JP, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapEUC_JP, NULL,
 		   sizeof(LUmapEUC_JP) / sizeof(pg_local_to_utf), 0, PG_EUC_JP, len);
@@ -59,9 +57,7 @@ utf8_to_euc_jp(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_JP);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_EUC_JP);
 
 	UtfToLocal(src, dest, ULmapEUC_JP, NULL,
 		   sizeof(ULmapEUC_JP) / sizeof(pg_utf_to_local), 0, PG_EUC_JP, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_euc_kr/utf8_and_euc_kr.c b/src/backend/utils/mb/conversion_procs/utf8_and_euc_kr/utf8_and_euc_kr.c
index 9e3f43dd7b3..cfbc554e4d1 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_euc_kr/utf8_and_euc_kr.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_euc_kr/utf8_and_euc_kr.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_kr/utf8_and_euc_kr.c,v 1.20 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_kr/utf8_and_euc_kr.c,v 1.21 2009/01/29 19:23:40 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ euc_kr_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_KR);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_KR, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapEUC_KR, NULL,
 		   sizeof(LUmapEUC_KR) / sizeof(pg_local_to_utf), 0, PG_EUC_KR, len);
@@ -59,9 +57,7 @@ utf8_to_euc_kr(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_KR);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_EUC_KR);
 
 	UtfToLocal(src, dest, ULmapEUC_KR, NULL,
 		   sizeof(ULmapEUC_KR) / sizeof(pg_utf_to_local), 0, PG_EUC_KR, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_euc_tw/utf8_and_euc_tw.c b/src/backend/utils/mb/conversion_procs/utf8_and_euc_tw/utf8_and_euc_tw.c
index b10b29d17dd..e18c3ff6b17 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_euc_tw/utf8_and_euc_tw.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_euc_tw/utf8_and_euc_tw.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_tw/utf8_and_euc_tw.c,v 1.20 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_euc_tw/utf8_and_euc_tw.c,v 1.21 2009/01/29 19:23:40 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ euc_tw_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_EUC_TW);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_EUC_TW, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapEUC_TW, NULL,
 		   sizeof(LUmapEUC_TW) / sizeof(pg_local_to_utf), 0, PG_EUC_TW, len);
@@ -59,9 +57,7 @@ utf8_to_euc_tw(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_EUC_TW);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_EUC_TW);
 
 	UtfToLocal(src, dest, ULmapEUC_TW, NULL,
 		   sizeof(ULmapEUC_TW) / sizeof(pg_utf_to_local), 0, PG_EUC_TW, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_gb18030/utf8_and_gb18030.c b/src/backend/utils/mb/conversion_procs/utf8_and_gb18030/utf8_and_gb18030.c
index 4be3489b644..25ecee6b58f 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_gb18030/utf8_and_gb18030.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_gb18030/utf8_and_gb18030.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_gb18030/utf8_and_gb18030.c,v 1.21 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_gb18030/utf8_and_gb18030.c,v 1.22 2009/01/29 19:23:40 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ gb18030_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_GB18030);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_GB18030, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapGB18030, NULL,
 		 sizeof(LUmapGB18030) / sizeof(pg_local_to_utf), 0, PG_GB18030, len);
@@ -59,9 +57,7 @@ utf8_to_gb18030(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_GB18030);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_GB18030);
 
 	UtfToLocal(src, dest, ULmapGB18030, NULL,
 		 sizeof(ULmapGB18030) / sizeof(pg_utf_to_local), 0, PG_GB18030, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_gbk/utf8_and_gbk.c b/src/backend/utils/mb/conversion_procs/utf8_and_gbk/utf8_and_gbk.c
index b6b5a5a826c..f33a22b4fbe 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_gbk/utf8_and_gbk.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_gbk/utf8_and_gbk.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_gbk/utf8_and_gbk.c,v 1.18 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_gbk/utf8_and_gbk.c,v 1.19 2009/01/29 19:23:41 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ gbk_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_GBK);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_GBK, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapGBK, NULL,
 			   sizeof(LUmapGBK) / sizeof(pg_local_to_utf), 0, PG_GBK, len);
@@ -59,9 +57,7 @@ utf8_to_gbk(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_GBK);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_GBK);
 
 	UtfToLocal(src, dest, ULmapGBK, NULL,
 			   sizeof(ULmapGBK) / sizeof(pg_utf_to_local), 0, PG_GBK, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_iso8859/utf8_and_iso8859.c b/src/backend/utils/mb/conversion_procs/utf8_and_iso8859/utf8_and_iso8859.c
index 8996a8723d5..539a8d2593a 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_iso8859/utf8_and_iso8859.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_iso8859/utf8_and_iso8859.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_iso8859/utf8_and_iso8859.c,v 1.29 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_iso8859/utf8_and_iso8859.c,v 1.30 2009/01/29 19:23:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -120,8 +120,7 @@ iso8859_to_utf8(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	int			i;
 
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(-1, PG_UTF8);
 
 	for (i = 0; i < sizeof(maps) / sizeof(pg_conv_map); i++)
 	{
@@ -148,8 +147,7 @@ utf8_to_iso8859(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	int			i;
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, -1);
 
 	for (i = 0; i < sizeof(maps) / sizeof(pg_conv_map); i++)
 	{
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_iso8859_1/utf8_and_iso8859_1.c b/src/backend/utils/mb/conversion_procs/utf8_and_iso8859_1/utf8_and_iso8859_1.c
index 64943800762..cd34b0f05cf 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_iso8859_1/utf8_and_iso8859_1.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_iso8859_1/utf8_and_iso8859_1.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_iso8859_1/utf8_and_iso8859_1.c,v 1.21 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_iso8859_1/utf8_and_iso8859_1.c,v 1.22 2009/01/29 19:23:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ iso8859_1_to_utf8(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	unsigned short c;
 
-	Assert(PG_GETARG_INT32(0) == PG_LATIN1);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_LATIN1, PG_UTF8);
 
 	while (len > 0)
 	{
@@ -75,9 +73,7 @@ utf8_to_iso8859_1(PG_FUNCTION_ARGS)
 	unsigned short c,
 				c1;
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_LATIN1);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_LATIN1);
 
 	while (len > 0)
 	{
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_johab/utf8_and_johab.c b/src/backend/utils/mb/conversion_procs/utf8_and_johab/utf8_and_johab.c
index 9bed1f75040..4df9d64ce22 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_johab/utf8_and_johab.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_johab/utf8_and_johab.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_johab/utf8_and_johab.c,v 1.20 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_johab/utf8_and_johab.c,v 1.21 2009/01/29 19:23:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ johab_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_JOHAB);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_JOHAB, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapJOHAB, NULL,
 			 sizeof(LUmapJOHAB) / sizeof(pg_local_to_utf), 0, PG_JOHAB, len);
@@ -59,9 +57,7 @@ utf8_to_johab(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_JOHAB);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_JOHAB);
 
 	UtfToLocal(src, dest, ULmapJOHAB, NULL,
 			 sizeof(ULmapJOHAB) / sizeof(pg_utf_to_local), 0, PG_JOHAB, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_shift_jis_2004/utf8_and_shift_jis_2004.c b/src/backend/utils/mb/conversion_procs/utf8_and_shift_jis_2004/utf8_and_shift_jis_2004.c
index f3d35e70d94..c006a11e9d1 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_shift_jis_2004/utf8_and_shift_jis_2004.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_shift_jis_2004/utf8_and_shift_jis_2004.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_shift_jis_2004/utf8_and_shift_jis_2004.c,v 1.4 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_shift_jis_2004/utf8_and_shift_jis_2004.c,v 1.5 2009/01/29 19:23:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -44,9 +44,7 @@ shift_jis_2004_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_SHIFT_JIS_2004);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_SHIFT_JIS_2004, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapSHIFT_JIS_2004, LUmapSHIFT_JIS_2004_combined,
 			   sizeof(LUmapSHIFT_JIS_2004) / sizeof(pg_local_to_utf),
@@ -63,9 +61,7 @@ utf8_to_shift_jis_2004(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_SHIFT_JIS_2004);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_SHIFT_JIS_2004);
 
 	UtfToLocal(src, dest, ULmapSHIFT_JIS_2004, ULmapSHIFT_JIS_2004_combined,
 			   sizeof(ULmapSHIFT_JIS_2004) / sizeof(pg_utf_to_local),
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_sjis/utf8_and_sjis.c b/src/backend/utils/mb/conversion_procs/utf8_and_sjis/utf8_and_sjis.c
index 62b76834b65..2ed8964b578 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_sjis/utf8_and_sjis.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_sjis/utf8_and_sjis.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_sjis/utf8_and_sjis.c,v 1.18 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_sjis/utf8_and_sjis.c,v 1.19 2009/01/29 19:23:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ sjis_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_SJIS);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_SJIS, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapSJIS, NULL,
 			   sizeof(LUmapSJIS) / sizeof(pg_local_to_utf), 0, PG_SJIS, len);
@@ -59,9 +57,7 @@ utf8_to_sjis(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_SJIS);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_SJIS);
 
 	UtfToLocal(src, dest, ULmapSJIS, NULL,
 			   sizeof(ULmapSJIS) / sizeof(pg_utf_to_local), 0, PG_SJIS, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_uhc/utf8_and_uhc.c b/src/backend/utils/mb/conversion_procs/utf8_and_uhc/utf8_and_uhc.c
index 77fa7a46de3..5d9c61076a5 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_uhc/utf8_and_uhc.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_uhc/utf8_and_uhc.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_uhc/utf8_and_uhc.c,v 1.18 2009/01/01 17:23:52 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_uhc/utf8_and_uhc.c,v 1.19 2009/01/29 19:23:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -42,9 +42,7 @@ uhc_to_utf8(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UHC);
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UHC, PG_UTF8);
 
 	LocalToUtf(src, dest, LUmapUHC, NULL,
 			   sizeof(LUmapUHC) / sizeof(pg_local_to_utf), 0, PG_UHC, len);
@@ -59,9 +57,7 @@ utf8_to_uhc(PG_FUNCTION_ARGS)
 	unsigned char *dest = (unsigned char *) PG_GETARG_CSTRING(3);
 	int			len = PG_GETARG_INT32(4);
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(PG_GETARG_INT32(1) == PG_UHC);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, PG_UHC);
 
 	UtfToLocal(src, dest, ULmapUHC, NULL,
 			   sizeof(ULmapUHC) / sizeof(pg_utf_to_local), 0, PG_UHC, len);
diff --git a/src/backend/utils/mb/conversion_procs/utf8_and_win/utf8_and_win.c b/src/backend/utils/mb/conversion_procs/utf8_and_win/utf8_and_win.c
index 67b4a6cbe61..e39d814e87c 100644
--- a/src/backend/utils/mb/conversion_procs/utf8_and_win/utf8_and_win.c
+++ b/src/backend/utils/mb/conversion_procs/utf8_and_win/utf8_and_win.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_win/utf8_and_win.c,v 1.13 2009/01/01 17:23:53 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/mb/conversion_procs/utf8_and_win/utf8_and_win.c,v 1.14 2009/01/29 19:23:42 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -110,8 +110,7 @@ win_to_utf8(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	int			i;
 
-	Assert(PG_GETARG_INT32(1) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(-1, PG_UTF8);
 
 	for (i = 0; i < sizeof(maps) / sizeof(pg_conv_map); i++)
 	{
@@ -138,8 +137,7 @@ utf8_to_win(PG_FUNCTION_ARGS)
 	int			len = PG_GETARG_INT32(4);
 	int			i;
 
-	Assert(PG_GETARG_INT32(0) == PG_UTF8);
-	Assert(len >= 0);
+	CHECK_ENCODING_CONVERSION_ARGS(PG_UTF8, -1);
 
 	for (i = 0; i < sizeof(maps) / sizeof(pg_conv_map); i++)
 	{
diff --git a/src/backend/utils/mb/wchar.c b/src/backend/utils/mb/wchar.c
index 2c6c3f3ff1c..4fb1ca8035a 100644
--- a/src/backend/utils/mb/wchar.c
+++ b/src/backend/utils/mb/wchar.c
@@ -1,7 +1,7 @@
 /*
  * conversion functions between pg_wchar and multibyte streams.
  * Tatsuo Ishii
- * $PostgreSQL: pgsql/src/backend/utils/mb/wchar.c,v 1.68 2008/10/29 08:04:53 petere Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/mb/wchar.c,v 1.69 2009/01/29 19:23:42 tgl Exp $
  *
  */
 /* can be used in either frontend or backend */
@@ -1550,6 +1550,39 @@ pg_verify_mbstr_len(int encoding, const char *mbstr, int len, bool noError)
 }
 
 /*
+ * check_encoding_conversion_args: check arguments of a conversion function
+ *
+ * "expected" arguments can be either an encoding ID or -1 to indicate that
+ * the caller will check whether it accepts the ID.
+ *
+ * Note: the errors here are not really user-facing, so elog instead of
+ * ereport seems sufficient.  Also, we trust that the "expected" encoding
+ * arguments are valid encoding IDs, but we don't trust the actuals.
+ */
+void
+check_encoding_conversion_args(int src_encoding,
+							   int dest_encoding,
+							   int len,
+							   int expected_src_encoding,
+							   int expected_dest_encoding)
+{
+	if (!PG_VALID_ENCODING(src_encoding))
+		elog(ERROR, "invalid source encoding ID: %d", src_encoding);
+	if (src_encoding != expected_src_encoding && expected_src_encoding >= 0)
+		elog(ERROR, "expected source encoding \"%s\", but got \"%s\"",
+			 pg_enc2name_tbl[expected_src_encoding].name,
+			 pg_enc2name_tbl[src_encoding].name);
+	if (!PG_VALID_ENCODING(dest_encoding))
+		elog(ERROR, "invalid destination encoding ID: %d", dest_encoding);
+	if (dest_encoding != expected_dest_encoding && expected_dest_encoding >= 0)
+		elog(ERROR, "expected destination encoding \"%s\", but got \"%s\"",
+			 pg_enc2name_tbl[expected_dest_encoding].name,
+			 pg_enc2name_tbl[dest_encoding].name);
+	if (len < 0)
+		elog(ERROR, "encoding conversion length must not be negative");
+}
+
+/*
  * report_invalid_encoding: complain about invalid multibyte character
  *
  * note: len is remaining length of string, not length of character;
diff --git a/src/include/mb/pg_wchar.h b/src/include/mb/pg_wchar.h
index dc89af9d507..65c99a2797f 100644
--- a/src/include/mb/pg_wchar.h
+++ b/src/include/mb/pg_wchar.h
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/mb/pg_wchar.h,v 1.82 2009/01/04 18:37:36 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/mb/pg_wchar.h,v 1.83 2009/01/29 19:23:42 tgl Exp $
  *
  *	NOTES
  *		This is used both by the backend and by libpq, but should not be
@@ -325,6 +325,19 @@ typedef struct
 	uint32		utf2;			/* UTF-8 code 2 */
 } pg_local_to_utf_combined;
 
+/*
+ * Support macro for encoding conversion functions to validate their
+ * arguments.  (This could be made more compact if we included fmgr.h
+ * here, but we don't want to do that because this header file is also
+ * used by frontends.)
+ */
+#define CHECK_ENCODING_CONVERSION_ARGS(srcencoding,destencoding) \
+	check_encoding_conversion_args(PG_GETARG_INT32(0), \
+								   PG_GETARG_INT32(1), \
+								   PG_GETARG_INT32(4), \
+								   (srcencoding), \
+								   (destencoding))
+
 
 /*
  * These functions are considered part of libpq's exported API and
@@ -408,6 +421,12 @@ extern bool pg_verify_mbstr(int encoding, const char *mbstr, int len,
 extern int pg_verify_mbstr_len(int encoding, const char *mbstr, int len,
 					bool noError);
 
+extern void check_encoding_conversion_args(int src_encoding,
+										   int dest_encoding,
+										   int len,
+										   int expected_src_encoding,
+										   int expected_dest_encoding);
+
 extern void report_invalid_encoding(int encoding, const char *mbstr, int len);
 extern void report_untranslatable_char(int src_encoding, int dest_encoding,
 						   const char *mbstr, int len);