Remove wchar.c Asserts that were stricter than the main code

Assert errors were thrown for functions being passed invalid encodings,
while the main code handled it just fine.

Also document that libpq's PQclientEncoding() returns -1 for an encoding
lookup failure.

Per report from Peter Geoghegan

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index 22815bc9ad8e54f09d3ed120d58f24d2c5fe8fd2..be0d602508df122b166531032578b6d6aa5cfbd7 100644 (file)
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -5377,7 +5377,8 @@ int PQclientEncoding(const PGconn *<replaceable>conn</replaceable>);
 </synopsis>
 
       Note that it returns the encoding ID, not a symbolic string
-      such as <literal>EUC_JP</literal>. To convert an encoding ID to an encoding name, you
+      such as <literal>EUC_JP</literal>. If unsuccessful, it returns -1.
+      To convert an encoding ID to an encoding name, you
       can use:
 
 <synopsis>

diff --git a/src/backend/utils/mb/wchar.c b/src/backend/utils/mb/wchar.c
index 6d03a10854e3efc877970d135fcbf3406c935f9c..5f65f1bc89987ad7c34c9b2da5e473afe4ba1974 100644 (file)
--- a/src/backend/utils/mb/wchar.c
+++ b/src/backend/utils/mb/wchar.c
@@ -1778,10 +1778,7 @@ pg_mic_mblen(const unsigned char *mbstr)
 int
 pg_encoding_mblen(int encoding, const char *mbstr)
 {
-       Assert(PG_VALID_ENCODING(encoding));
-
-       return ((encoding >= 0 &&
-                        encoding < sizeof(pg_wchar_table) / sizeof(pg_wchar_tbl)) ?
+       return (PG_VALID_ENCODING(encoding) ?
                ((*pg_wchar_table[encoding].mblen) ((const unsigned char *) mbstr)) :
        ((*pg_wchar_table[PG_SQL_ASCII].mblen) ((const unsigned char *) mbstr)));
 }
@@ -1792,10 +1789,7 @@ pg_encoding_mblen(int encoding, const char *mbstr)
 int
 pg_encoding_dsplen(int encoding, const char *mbstr)
 {
-       Assert(PG_VALID_ENCODING(encoding));
-
-       return ((encoding >= 0 &&
-                        encoding < sizeof(pg_wchar_table) / sizeof(pg_wchar_tbl)) ?
+       return (PG_VALID_ENCODING(encoding) ?
           ((*pg_wchar_table[encoding].dsplen) ((const unsigned char *) mbstr)) :
        ((*pg_wchar_table[PG_SQL_ASCII].dsplen) ((const unsigned char *) mbstr)));
 }
@@ -1808,12 +1802,9 @@ pg_encoding_dsplen(int encoding, const char *mbstr)
 int
 pg_encoding_verifymb(int encoding, const char *mbstr, int len)
 {
-       Assert(PG_VALID_ENCODING(encoding));
-
-       return ((encoding >= 0 &&
-                        encoding < sizeof(pg_wchar_table) / sizeof(pg_wchar_tbl)) ?
-                       ((*pg_wchar_table[encoding].mbverify) ((const unsigned char *) mbstr, len)) :
-                       ((*pg_wchar_table[PG_SQL_ASCII].mbverify) ((const unsigned char *) mbstr, len)));
+       return (PG_VALID_ENCODING(encoding) ?
+               ((*pg_wchar_table[encoding].mbverify) ((const unsigned char *) mbstr, len)) :
+       ((*pg_wchar_table[PG_SQL_ASCII].mbverify) ((const unsigned char *) mbstr, len)));
 }
 
 /*