Expose quote_literal_cstr() from core.

This eliminates the need for inefficient implementions of this
functionality in both contrib/dblink and contrib/tablefunc, so remove
them.  The upcoming patch implementing an in-core format() function
will also require this functionality.

In passing, add some regression tests.

1 files changed, 0 insertions, 20 deletions

diff --git a/contrib/tablefunc/tablefunc.c b/contrib/tablefunc/tablefunc.c
index ea2f2e15b0a..2e9ea1a626e 100644
--- a/contrib/tablefunc/tablefunc.c
+++ b/contrib/tablefunc/tablefunc.c
@@ -85,7 +85,6 @@ static Tuplestorestate *build_tuplestore_recursively(char *key_fld,
 							 MemoryContext per_query_ctx,
 							 AttInMetadata *attinmeta,
 							 Tuplestorestate *tupstore);
-static char *quote_literal_cstr(char *rawstr);
 
 typedef struct
 {
@@ -1564,22 +1563,3 @@ compatCrosstabTupleDescs(TupleDesc ret_tupdesc, TupleDesc sql_tupdesc)
 	/* OK, the two tupdescs are compatible for our purposes */
 	return true;
 }
-
-/*
- * Return a properly quoted literal value.
- * Uses quote_literal in quote.c
- */
-static char *
-quote_literal_cstr(char *rawstr)
-{
-	text	   *rawstr_text;
-	text	   *result_text;
-	char	   *result;
-
-	rawstr_text = cstring_to_text(rawstr);
-	result_text = DatumGetTextP(DirectFunctionCall1(quote_literal,
-											  PointerGetDatum(rawstr_text)));
-	result = text_to_cstring(result_text);
-
-	return result;
-}