1 files changed, 105 insertions, 0 deletions
diff --git a/src/backend/tsearch/dict_simple.c b/src/backend/tsearch/dict_simple.c
new file mode 100644
index 0000000..214d44e
--- /dev/null
+++ b/src/backend/tsearch/dict_simple.c
@@ -0,0 +1,105 @@
+/*-------------------------------------------------------------------------
+ *
+ * dict_simple.c
+ *		Simple dictionary: just lowercase and check for stopword
+ *
+ * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/tsearch/dict_simple.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "commands/defrem.h"
+#include "tsearch/ts_locale.h"
+#include "tsearch/ts_utils.h"
+#include "utils/builtins.h"
+
+
+typedef struct
+{
+	StopList	stoplist;
+	bool		accept;
+} DictSimple;
+
+
+Datum
+dsimple_init(PG_FUNCTION_ARGS)
+{
+	List	   *dictoptions = (List *) PG_GETARG_POINTER(0);
+	DictSimple *d = (DictSimple *) palloc0(sizeof(DictSimple));
+	bool		stoploaded = false,
+				acceptloaded = false;
+	ListCell   *l;
+
+	d->accept = true;			/* default */
+
+	foreach(l, dictoptions)
+	{
+		DefElem    *defel = (DefElem *) lfirst(l);
+
+		if (strcmp(defel->defname, "stopwords") == 0)
+		{
+			if (stoploaded)
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("multiple StopWords parameters")));
+			readstoplist(defGetString(defel), &d->stoplist, lowerstr);
+			stoploaded = true;
+		}
+		else if (strcmp(defel->defname, "accept") == 0)
+		{
+			if (acceptloaded)
+				ereport(ERROR,
+						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+						 errmsg("multiple Accept parameters")));
+			d->accept = defGetBoolean(defel);
+			acceptloaded = true;
+		}
+		else
+		{
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+					 errmsg("unrecognized simple dictionary parameter: \"%s\"",
+							defel->defname)));
+		}
+	}
+
+	PG_RETURN_POINTER(d);
+}
+
+Datum
+dsimple_lexize(PG_FUNCTION_ARGS)
+{
+	DictSimple *d = (DictSimple *) PG_GETARG_POINTER(0);
+	char	   *in = (char *) PG_GETARG_POINTER(1);
+	int32		len = PG_GETARG_INT32(2);
+	char	   *txt;
+	TSLexeme   *res;
+
+	txt = lowerstr_with_len(in, len);
+
+	if (*txt == '\0' || searchstoplist(&(d->stoplist), txt))
+	{
+		/* reject as stopword */
+		pfree(txt);
+		res = palloc0(sizeof(TSLexeme) * 2);
+		PG_RETURN_POINTER(res);
+	}
+	else if (d->accept)
+	{
+		/* accept */
+		res = palloc0(sizeof(TSLexeme) * 2);
+		res[0].lexeme = txt;
+		PG_RETURN_POINTER(res);
+	}
+	else
+	{
+		/* report as unrecognized */
+		pfree(txt);
+		PG_RETURN_POINTER(NULL);
+	}
+}