1 files changed, 408 insertions, 0 deletions
diff --git a/contrib/citext/citext.c b/contrib/citext/citext.c
new file mode 100644
index 0000000..df13946
--- /dev/null
+++ b/contrib/citext/citext.c
@@ -0,0 +1,408 @@
+/*
+ * contrib/citext/citext.c
+ */
+#include "postgres.h"
+
+#include "catalog/pg_collation.h"
+#include "common/hashfn.h"
+#include "utils/builtins.h"
+#include "utils/formatting.h"
+#include "utils/varlena.h"
+
+PG_MODULE_MAGIC;
+
+/*
+ *		====================
+ *		FORWARD DECLARATIONS
+ *		====================
+ */
+
+static int32 citextcmp(text *left, text *right, Oid collid);
+static int32 internal_citext_pattern_cmp(text *left, text *right, Oid collid);
+
+/*
+ *		=================
+ *		UTILITY FUNCTIONS
+ *		=================
+ */
+
+/*
+ * citextcmp()
+ * Internal comparison function for citext strings.
+ * Returns int32 negative, zero, or positive.
+ */
+static int32
+citextcmp(text *left, text *right, Oid collid)
+{
+	char	   *lcstr,
+			   *rcstr;
+	int32		result;
+
+	/*
+	 * We must do our str_tolower calls with DEFAULT_COLLATION_OID, not the
+	 * input collation as you might expect.  This is so that the behavior of
+	 * citext's equality and hashing functions is not collation-dependent.  We
+	 * should change this once the core infrastructure is able to cope with
+	 * collation-dependent equality and hashing functions.
+	 */
+
+	lcstr = str_tolower(VARDATA_ANY(left), VARSIZE_ANY_EXHDR(left), DEFAULT_COLLATION_OID);
+	rcstr = str_tolower(VARDATA_ANY(right), VARSIZE_ANY_EXHDR(right), DEFAULT_COLLATION_OID);
+
+	result = varstr_cmp(lcstr, strlen(lcstr),
+						rcstr, strlen(rcstr),
+						collid);
+
+	pfree(lcstr);
+	pfree(rcstr);
+
+	return result;
+}
+
+/*
+ * citext_pattern_cmp()
+ * Internal character-by-character comparison function for citext strings.
+ * Returns int32 negative, zero, or positive.
+ */
+static int32
+internal_citext_pattern_cmp(text *left, text *right, Oid collid)
+{
+	char	   *lcstr,
+			   *rcstr;
+	int			llen,
+				rlen;
+	int32		result;
+
+	lcstr = str_tolower(VARDATA_ANY(left), VARSIZE_ANY_EXHDR(left), DEFAULT_COLLATION_OID);
+	rcstr = str_tolower(VARDATA_ANY(right), VARSIZE_ANY_EXHDR(right), DEFAULT_COLLATION_OID);
+
+	llen = strlen(lcstr);
+	rlen = strlen(rcstr);
+
+	result = memcmp((void *) lcstr, (void *) rcstr, Min(llen, rlen));
+	if (result == 0)
+	{
+		if (llen < rlen)
+			result = -1;
+		else if (llen > rlen)
+			result = 1;
+	}
+
+	pfree(lcstr);
+	pfree(rcstr);
+
+	return result;
+}
+
+/*
+ *		==================
+ *		INDEXING FUNCTIONS
+ *		==================
+ */
+
+PG_FUNCTION_INFO_V1(citext_cmp);
+
+Datum
+citext_cmp(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	int32		result;
+
+	result = citextcmp(left, right, PG_GET_COLLATION());
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_INT32(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_pattern_cmp);
+
+Datum
+citext_pattern_cmp(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	int32		result;
+
+	result = internal_citext_pattern_cmp(left, right, PG_GET_COLLATION());
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_INT32(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_hash);
+
+Datum
+citext_hash(PG_FUNCTION_ARGS)
+{
+	text	   *txt = PG_GETARG_TEXT_PP(0);
+	char	   *str;
+	Datum		result;
+
+	str = str_tolower(VARDATA_ANY(txt), VARSIZE_ANY_EXHDR(txt), DEFAULT_COLLATION_OID);
+	result = hash_any((unsigned char *) str, strlen(str));
+	pfree(str);
+
+	/* Avoid leaking memory for toasted inputs */
+	PG_FREE_IF_COPY(txt, 0);
+
+	PG_RETURN_DATUM(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_hash_extended);
+
+Datum
+citext_hash_extended(PG_FUNCTION_ARGS)
+{
+	text	   *txt = PG_GETARG_TEXT_PP(0);
+	uint64		seed = PG_GETARG_INT64(1);
+	char	   *str;
+	Datum		result;
+
+	str = str_tolower(VARDATA_ANY(txt), VARSIZE_ANY_EXHDR(txt), DEFAULT_COLLATION_OID);
+	result = hash_any_extended((unsigned char *) str, strlen(str), seed);
+	pfree(str);
+
+	/* Avoid leaking memory for toasted inputs */
+	PG_FREE_IF_COPY(txt, 0);
+
+	PG_RETURN_DATUM(result);
+}
+
+/*
+ *		==================
+ *		OPERATOR FUNCTIONS
+ *		==================
+ */
+
+PG_FUNCTION_INFO_V1(citext_eq);
+
+Datum
+citext_eq(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	char	   *lcstr,
+			   *rcstr;
+	bool		result;
+
+	/* We can't compare lengths in advance of downcasing ... */
+
+	lcstr = str_tolower(VARDATA_ANY(left), VARSIZE_ANY_EXHDR(left), DEFAULT_COLLATION_OID);
+	rcstr = str_tolower(VARDATA_ANY(right), VARSIZE_ANY_EXHDR(right), DEFAULT_COLLATION_OID);
+
+	/*
+	 * Since we only care about equality or not-equality, we can avoid all the
+	 * expense of strcoll() here, and just do bitwise comparison.
+	 */
+	result = (strcmp(lcstr, rcstr) == 0);
+
+	pfree(lcstr);
+	pfree(rcstr);
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_ne);
+
+Datum
+citext_ne(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	char	   *lcstr,
+			   *rcstr;
+	bool		result;
+
+	/* We can't compare lengths in advance of downcasing ... */
+
+	lcstr = str_tolower(VARDATA_ANY(left), VARSIZE_ANY_EXHDR(left), DEFAULT_COLLATION_OID);
+	rcstr = str_tolower(VARDATA_ANY(right), VARSIZE_ANY_EXHDR(right), DEFAULT_COLLATION_OID);
+
+	/*
+	 * Since we only care about equality or not-equality, we can avoid all the
+	 * expense of strcoll() here, and just do bitwise comparison.
+	 */
+	result = (strcmp(lcstr, rcstr) != 0);
+
+	pfree(lcstr);
+	pfree(rcstr);
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_lt);
+
+Datum
+citext_lt(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	bool		result;
+
+	result = citextcmp(left, right, PG_GET_COLLATION()) < 0;
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_le);
+
+Datum
+citext_le(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	bool		result;
+
+	result = citextcmp(left, right, PG_GET_COLLATION()) <= 0;
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_gt);
+
+Datum
+citext_gt(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	bool		result;
+
+	result = citextcmp(left, right, PG_GET_COLLATION()) > 0;
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_ge);
+
+Datum
+citext_ge(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	bool		result;
+
+	result = citextcmp(left, right, PG_GET_COLLATION()) >= 0;
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_pattern_lt);
+
+Datum
+citext_pattern_lt(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	bool		result;
+
+	result = internal_citext_pattern_cmp(left, right, PG_GET_COLLATION()) < 0;
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_pattern_le);
+
+Datum
+citext_pattern_le(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	bool		result;
+
+	result = internal_citext_pattern_cmp(left, right, PG_GET_COLLATION()) <= 0;
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_pattern_gt);
+
+Datum
+citext_pattern_gt(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	bool		result;
+
+	result = internal_citext_pattern_cmp(left, right, PG_GET_COLLATION()) > 0;
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_pattern_ge);
+
+Datum
+citext_pattern_ge(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	bool		result;
+
+	result = internal_citext_pattern_cmp(left, right, PG_GET_COLLATION()) >= 0;
+
+	PG_FREE_IF_COPY(left, 0);
+	PG_FREE_IF_COPY(right, 1);
+
+	PG_RETURN_BOOL(result);
+}
+
+/*
+ *		===================
+ *		AGGREGATE FUNCTIONS
+ *		===================
+ */
+
+PG_FUNCTION_INFO_V1(citext_smaller);
+
+Datum
+citext_smaller(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	text	   *result;
+
+	result = citextcmp(left, right, PG_GET_COLLATION()) < 0 ? left : right;
+	PG_RETURN_TEXT_P(result);
+}
+
+PG_FUNCTION_INFO_V1(citext_larger);
+
+Datum
+citext_larger(PG_FUNCTION_ARGS)
+{
+	text	   *left = PG_GETARG_TEXT_PP(0);
+	text	   *right = PG_GETARG_TEXT_PP(1);
+	text	   *result;
+
+	result = citextcmp(left, right, PG_GET_COLLATION()) > 0 ? left : right;
+	PG_RETURN_TEXT_P(result);
+}