Fix: allow (re)setting the current catalog

driver/catalogue.c

@@ -94,6 +94,36 @@ SQLRETURN EsSQLStatisticsW(
 #	undef STATISTICS_EMPTY
 }
 
+BOOL TEST_API set_current_catalog(esodbc_dbc_st *dbc, wstr_st *catalog)
+{
+	if (dbc->catalog.cnt) {
+		DBGH(dbc, "catalog already set to `" LWPDL "`.", LWSTR(&dbc->catalog));
+		if (! EQ_WSTR(&dbc->catalog, catalog)) {
+			/* this should never happen, as cluster's name is not updateable
+			 * on the fly. */
+			ERRH(dbc, "overwriting previously set catalog value!");
+			free(dbc->catalog.str);
+			dbc->catalog.str = NULL;
+			dbc->catalog.cnt = 0;
+		} else {
+			return FALSE;
+		}
+	}
+	if (! catalog->cnt) {
+		WARNH(dbc, "attempting to set catalog name to empty value.");
+		return FALSE;
+	}
+	if (! (dbc->catalog.str = malloc((catalog->cnt + 1) * sizeof(SQLWCHAR)))) {
+		ERRNH(dbc, "OOM for %zu wchars.", catalog->cnt + 1);
+		return FALSE;
+	}
+	wmemcpy(dbc->catalog.str, catalog->str, catalog->cnt);
+	dbc->catalog.str[catalog->cnt] = L'\0';
+	dbc->catalog.cnt = catalog->cnt;
+	INFOH(dbc, "current catalog name: `" LWPDL "`.", LWSTR(&dbc->catalog));
+
+	return TRUE;
+}
 
 /* writes into 'dest', of size 'room', the current requested attr. of 'dbc'.
  * returns negative on error, or the char count written otherwise */
@@ -175,6 +205,9 @@ SQLSMALLINT fetch_server_attr(esodbc_dbc_st *dbc, SQLINTEGER attr_id,
 			/* 0-term room left out when binding */
 			buff[attr_val.cnt] = L'\0'; /* write_wstr() expects the 0-term */
 		}
+		if (attr_id == SQL_ATTR_CURRENT_CATALOG) {
+			set_current_catalog(dbc, &attr_val);
+		}
 	}
 	DBGH(dbc, "attribute %ld value: `" LWPDL "`.", attr_id, LWSTR(&attr_val));
 

driver/catalogue.h

@@ -13,6 +13,7 @@
 
 SQLSMALLINT fetch_server_attr(esodbc_dbc_st *dbc, SQLINTEGER attr_id,
 	SQLWCHAR *dest, SQLSMALLINT room);
+BOOL TEST_API set_current_catalog(esodbc_dbc_st *dbc, wstr_st *catalog);
 
 
 SQLRETURN EsSQLStatisticsW(

driver/connect.c

@@ -1528,6 +1528,13 @@ void cleanup_dbc(esodbc_dbc_st *dbc)
 		dbc->srv_ver.string.str = NULL;
 		dbc->srv_ver.string.cnt = 0;
 	}
+	if (dbc->catalog.str) {
+		free(dbc->catalog.str);
+		dbc->catalog.str = NULL;
+		dbc->catalog.cnt = 0;
+	} else {
+		assert(dbc->catalog.cnt == 0);
+	}
 
 	assert(dbc->abuff == NULL);
 	cleanup_curl(dbc);
@@ -3082,7 +3089,37 @@ SQLRETURN EsSQLDisconnect(SQLHDBC ConnectionHandle)
 	return SQL_SUCCESS;
 }
 
-
+/* ES/SQL doesn't support catalogs (yet). This function checks that a
+ * previously retrieved (and cached) catalog value is the same with what the
+ * app currently tries to set it to.
+ * Ideally, the app provided value would be cached here too (as per the spec:
+ * "SQL_ATTR_CURRENT_CATALOG can be set before or after connecting"), in case
+ * there's no connection "established" yet and checked at "establishment"
+ * time. But there's no client reported yet setting a catalog value before
+ * connecting. */
+static SQLRETURN check_catalog_name(esodbc_dbc_st *dbc, SQLWCHAR *name,
+	SQLINTEGER len)
+{
+	wstr_st catalog;
+	catalog.str = name;
+	if (len < 0) {
+		catalog.cnt = wcslen(name);
+	} else {
+		catalog.cnt = (size_t)len;
+	}
+	if (! EQ_WSTR(&dbc->catalog, &catalog)) {
+		if (! dbc->catalog.cnt) {
+			/* this will happen if the app tries to set a value that it
+			 * discovered over a different connection.
+			 * TODO on a first reported issue. */
+			WARNH(dbc, "connection's current catalog not yet set!");
+		}
+		ERRH(dbc, "setting catalog name not supported.");
+		RET_HDIAGS(dbc, SQL_STATE_HYC00);
+	}
+	WARNH(dbc, "ignoring attempt to set the current catalog.");
+	return SQL_SUCCESS;
+}
 
 /*
  * https://docs.microsoft.com/en-us/sql/odbc/reference/develop-app/unicode-drivers :
@@ -3222,8 +3259,7 @@ SQLRETURN EsSQLSetConnectAttrW(
 				/* string should be 0-term'd */
 				0 <= StringLength ? StringLength : SHRT_MAX,
 				(SQLWCHAR *)Value);
-			ERRH(dbc, "setting catalog name not supported.");
-			RET_HDIAGS(dbc, SQL_STATE_HYC00);
+			return check_catalog_name(dbc, (SQLWCHAR *)Value, StringLength);
 
 		case SQL_ATTR_TRACE:
 		case SQL_ATTR_TRACEFILE: /* DM-only */

driver/handles.h

@@ -131,9 +131,10 @@ typedef struct struct_dbc {
 
 	wstr_st dsn; /* data source name SQLGetInfo(SQL_DATA_SOURCE_NAME) */
 	wstr_st server; /* ~ name; requested with SQLGetInfo(SQL_SERVER_NAME) */
+	wstr_st catalog; /* cached value; checked against if app setting it */
 	union {
 		wstr_st string; /* version: SQLGetInfo(SQL_DBMS_VER)  */
-		unsigned char checking; /* first letter of DSN config option */
+		unsigned char checking; /* first letter of DSN config option value */
 	} srv_ver; /* server version */
 	cstr_st url; /* SQL URL (posts) */
 	cstr_st close_url; /* SQL close URL (posts) */

test/test_driverconnect.cc

@@ -7,6 +7,10 @@
 #include <gtest/gtest.h>
 #include "connected_dbc.h"
 
+extern "C" {
+#include "catalogue.h" /* set_current_catalog() */
+}
+
 namespace test {
 
 class DriverConnect : public ::testing::Test, public ConnectedDBC
@@ -70,5 +74,41 @@ TEST_F(DriverConnect, OutputTruncated)
 
 }
 
+TEST_F(DriverConnect, ReinitCurrentCatalog)
+{
+	ret = SQLDriverConnect(my_dbc, (SQLHWND)&types, (SQLWCHAR *)CONNECT_STRING,
+		sizeof(CONNECT_STRING) / sizeof(CONNECT_STRING[0]) - 1, NULL, 0,
+		&out_avail, ESODBC_SQL_DRIVER_TEST);
+	ASSERT_TRUE(SQL_SUCCEEDED(ret));
+
+	esodbc_dbc_st *dbc = (esodbc_dbc_st *)my_dbc;
+	wstr_st crr_cat = WSTR_INIT("crr_catalog");
+	ASSERT_TRUE(set_current_catalog(dbc, &crr_cat));
+	ASSERT_FALSE(set_current_catalog(dbc, &crr_cat));
+
+	wstr_st other_cat = WSTR_INIT("other_catalog");
+	ASSERT_TRUE(set_current_catalog(dbc, &other_cat));
+}
+
+TEST_F(DriverConnect, ResetCurrentCatalog)
+{
+	ret = SQLDriverConnect(my_dbc, (SQLHWND)&types, (SQLWCHAR *)CONNECT_STRING,
+		sizeof(CONNECT_STRING) / sizeof(CONNECT_STRING[0]) - 1, NULL, 0,
+		&out_avail, ESODBC_SQL_DRIVER_TEST);
+	ASSERT_TRUE(SQL_SUCCEEDED(ret));
+
+	esodbc_dbc_st *dbc = (esodbc_dbc_st *)my_dbc;
+	wstr_st crr_cat = WSTR_INIT("crr_catalog");
+	ASSERT_TRUE(set_current_catalog(dbc, &crr_cat));
+	ASSERT_TRUE(SQL_SUCCEEDED(SQLSetConnectAttrW(my_dbc,
+					SQL_ATTR_CURRENT_CATALOG, (SQLPOINTER)crr_cat.str,
+					(SQLINTEGER)crr_cat.cnt)));
+
+	wstr_st other_cat = WSTR_INIT("other_catalog");
+	ASSERT_FALSE(SQL_SUCCEEDED(SQLSetConnectAttrW(my_dbc,
+					SQL_ATTR_CURRENT_CATALOG, (SQLPOINTER)other_cat.str,
+					(SQLINTEGER)other_cat.cnt)));
+}
+
 } // test namespace