From 71e60a908de00f72902f5c7b79900d8afe535d92 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=9C=D0=B8=D1=85=D0=B0=D0=B8=D0=BB?=
 <41448637+mkgrgis@users.noreply.github.com>
Date: Thu, 2 Feb 2023 12:11:43 +0300
Subject: [PATCH] Add diagnostics for datatype error, fix special IEEE real
 values input for PostgreSQL All character case combinations is valid for
 special values, eg. NaN, Nan, NAN, nan etc. There is calulating optimisation
 for mass SELECT.

---
 sqlite_query.c | 52 ++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 42 insertions(+), 10 deletions(-)

diff --git a/sqlite_query.c b/sqlite_query.c
index 376a79e1..c568b05a 100644
--- a/sqlite_query.c
+++ b/sqlite_query.c
@@ -62,7 +62,7 @@
 #include "catalog/pg_type.h"
 
 static int32
-			sqlite_from_pgtyp(Oid pgtyp);
+			sqlite_eqv_from_pgtyp(Oid pgtyp);
 
 /*
  * convert_sqlite_to_pg: Convert Sqlite data into PostgreSQL's compatible data types
@@ -76,7 +76,9 @@ sqlite_convert_to_pg(Oid pgtyp, int pgtypmod, sqlite3_stmt * stmt, int attnum, A
 	HeapTuple	tuple;
 	int			typemod;
 	int			col_type;
-	int			sqlite_type;
+	int			sqlite_type_eqv_to_pg;
+	bool		special_IEEE_value = false;
+	double		special_IEEE_double;
 
 	/* get the type's output function */
 	tuple = SearchSysCache1(TYPEOID, ObjectIdGetDatum(pgtyp));
@@ -87,11 +89,43 @@ sqlite_convert_to_pg(Oid pgtyp, int pgtypmod, sqlite3_stmt * stmt, int attnum, A
 	typemod = ((Form_pg_type) GETSTRUCT(tuple))->typtypmod;
 	ReleaseSysCache(tuple);
 
-	sqlite_type = sqlite_from_pgtyp(pgtyp);
+	sqlite_type_eqv_to_pg = sqlite_eqv_from_pgtyp(pgtyp);
 	col_type = sqlite3_column_type(stmt, attnum);
 
-	if (sqlite_type != col_type && col_type == SQLITE3_TEXT)
-		elog(ERROR, "invalid input syntax for type =%d, column type =%d", sqlite_type, col_type);
+	if (sqlite_type_eqv_to_pg != col_type && col_type == SQLITE3_TEXT)
+	{
+		value_datum = CStringGetDatum((char*) sqlite3_column_text(stmt, attnum));
+
+		if (sqlite_type_eqv_to_pg == SQLITE_FLOAT && col_type == SQLITE3_TEXT)
+		{
+			bool        special_NaN = false;
+			bool        special_pos_infin = false;
+			bool        special_neg_infin = false;
+			char *p = 0;
+			char *uc_str = (char *) malloc( strlen((char *)value_datum) + 1 );
+			strcpy(uc_str, (char *)value_datum);
+			p = uc_str;
+			while (*p) {
+				*p = toupper(*p);
+				p++;
+			}
+			special_NaN       = !strcmp (uc_str, "NAN");
+			special_pos_infin = !strcmp (uc_str, "+INFINITY") ||
+								!strcmp (uc_str, "+INF") ||
+								!strcmp (uc_str, "INFINITY") ||
+								!strcmp (uc_str, "INF");
+			special_neg_infin = !strcmp (uc_str, "-INFINITY") ||
+								!strcmp (uc_str, "-INF");
+			free(uc_str);
+			special_IEEE_double = special_pos_infin ? (1.0 / 0.0) : special_neg_infin ? (-1.0 / 0.0) : (0.0 / 0.0); // +Inf, -Inf, NaN
+			special_IEEE_value = (special_NaN || special_pos_infin || special_neg_infin);
+		}
+
+		if (special_IEEE_value)
+			elog(DEBUG3, "sqlite_fdw : special IEEE value type =%d, column type =%d, value =%s", sqlite_type_eqv_to_pg, col_type, (char*)value_datum);
+		else
+			elog(ERROR, "invalid input syntax for type =%d, column type =%d, value =%s", sqlite_type_eqv_to_pg, col_type, (char*)value_datum);
+	}
 
 	switch (pgtyp)
 	{
@@ -141,15 +175,13 @@ sqlite_convert_to_pg(Oid pgtyp, int pgtypmod, sqlite3_stmt * stmt, int attnum, A
 			}
 		case FLOAT4OID:
 			{
-				double		value = sqlite3_column_double(stmt, attnum);
-
+				double		value = (special_IEEE_value) ? special_IEEE_double : sqlite3_column_double(stmt, attnum);
 				return Float4GetDatum((float4) value);
 				break;
 			}
 		case FLOAT8OID:
 			{
-				double		value = sqlite3_column_double(stmt, attnum);
-
+				double		value = (special_IEEE_value) ? special_IEEE_double : sqlite3_column_double(stmt, attnum);
 				return Float8GetDatum((float8) value);
 				break;
 			}
@@ -342,7 +374,7 @@ sqlite_bind_sql_var(Oid type, int attnum, Datum value, sqlite3_stmt * stmt, bool
  * Give SQLite data type from PG type
  */
 static int32
-sqlite_from_pgtyp(Oid type)
+sqlite_eqv_from_pgtyp(Oid type)
 {
 	switch (type)
 	{