CURRENT_DATABASE implementation. Established identity may also be used for isc_info_db_id datum

src/dsql/dsql.cpp

@@ -2230,6 +2230,9 @@ void DSQL_pretty(const dsql_nod* node, int column)
 	case nod_current_role:
 		verb = "current_role";
 		break;
+	case nod_current_database:
+		verb = "current_database";
+		break;
 	case nod_via:
 		verb = "via";
 		break;

src/dsql/gen.cpp

@@ -181,6 +181,10 @@ void GEN_expr( dsql_req* request, dsql_nod* node)
         stuff(request, blr_current_role);
         return;
 
+    case nod_current_database:
+        stuff(request, blr_current_database);
+        return;
+
 	case nod_udf:
 		gen_udf(request, node);
 		return;
@@ -2430,6 +2434,9 @@ static void gen_select( dsql_req* request, dsql_nod* rse)
 		case nod_current_role:
 			name_alias	= "ROLE";
 			break;
+		case nod_current_database:
+			name_alias	= "CURRENT_DATABASE";
+			break;
 		case nod_internal_info:
 			{
 			internal_info_id id =

src/dsql/keywords.cpp

@@ -28,7 +28,7 @@
  *  Contributor(s):
  * 
  *
- *  $Id: keywords.cpp,v 1.36 2004-10-17 08:47:12 dimitr Exp $
+ *  $Id: keywords.cpp,v 1.37 2004-11-11 05:37:20 skidder Exp $
  *
  */
 
@@ -104,6 +104,7 @@ static const TOK tokens[] = {
 	{CSTRING, "CSTRING", 1},
 	{CURRENT, "CURRENT", 1},
 	{CURRENT_CONNECTION, "CURRENT_CONNECTION", 2},
+	{CURRENT_DATABASE, "CURRENT_DATABASE", 2},
 	{CURRENT_DATE, "CURRENT_DATE", 2},
 	{CURRENT_ROLE, "CURRENT_ROLE", 2},
 	{CURRENT_TIME, "CURRENT_TIME", 2},

src/dsql/make.cpp

@@ -1109,6 +1109,14 @@ void MAKE_desc(dsc* desc, dsql_nod* node, dsql_nod* null_replacement)
 		desc->dsc_length = USERNAME_LENGTH + sizeof(USHORT);
 		return;
 
+	case nod_current_database:
+		desc->dsc_dtype = dtype_varying;
+		desc->dsc_scale = 0;
+		desc->dsc_flags = 0;
+		desc->dsc_ttype() = ttype_dynamic;
+		desc->dsc_length = DATABASE_NAME_LENGTH + sizeof(USHORT);
+		return;
+
 	case nod_internal_info:
 		desc->dsc_dtype = dtype_long;
 		desc->dsc_scale = 0;

src/dsql/node.h

@@ -334,7 +334,8 @@ enum nod_t
 	nod_param_val,		// default value for SP parameters support
 	nod_rows,	// ROWS support
 	nod_query_spec,
-	nod_equiv
+	nod_equiv,
+	nod_current_database
 };
 
 typedef nod_t NOD_TYPE;

src/dsql/parse.y

@@ -507,6 +507,7 @@ static LexerState lex;
 %token IIF
 %token SCALAR_ARRAY
 %token CROSS
+%token CURRENT_DATABASE
 
 /* precedence declarations for expression evaluation */
 
@@ -1334,6 +1335,7 @@ default_value	: constant
 			{ $$ = make_node (nod_user_name, (int) 0, NULL); }*/
 		| current_user
 		| current_role
+		| current_database
 		| internal_info
 		| null_value
 		| datetime_value_expression
@@ -2124,6 +2126,7 @@ keyword_or_column	: valid_symbol_name
 		| ROWS
 		| USING
 		| CROSS
+		| CURRENT_DATABASE
 		;
 
 col_opt		: ALTER
@@ -3676,6 +3679,7 @@ value	: column_name
 			{ $$ = $2; }
 		| current_user
 		| current_role
+		| current_database
 		| internal_info
 		| DB_KEY
 			{ $$ = make_node (nod_dbkey, 1, NULL); }
@@ -3804,6 +3808,10 @@ current_role	: CURRENT_ROLE
 			{ $$ = make_node (nod_current_role, 0, NULL); }
 		;
 
+current_database	: CURRENT_DATABASE
+			{ $$ = make_node (nod_current_database, 0, NULL); }
+		;
+
 internal_info	: CURRENT_CONNECTION
 			{ $$ = make_node (nod_internal_info, (int) e_internal_info_count,
 						MAKE_constant ((dsql_str*) internal_connection_id, CONSTANT_SLONG)); }

src/dsql/pass1.cpp

@@ -2644,6 +2644,7 @@ static bool invalid_reference(const dsql_ctx* context, const dsql_nod* node,
 		case nod_current_timestamp:
 		case nod_user_name:
 		case nod_current_role:
+		case nod_current_database:
 		case nod_internal_info:
 		case nod_dbkey:
 		case nod_derived_table:
@@ -4260,6 +4261,7 @@ static bool pass1_found_aggregate(const dsql_nod* node, USHORT check_scope_level
 		case nod_current_timestamp:
 		case nod_user_name:
 		case nod_current_role:
+		case nod_current_database:
 		case nod_internal_info:
 			return false;
 
@@ -4458,6 +4460,7 @@ static bool pass1_found_field(const dsql_nod* node, USHORT check_scope_level,
 		case nod_current_timestamp:
 		case nod_user_name:
 		case nod_current_role:
+		case nod_current_database:
 		case nod_internal_info:
 			return false;
 

src/jrd/blp.h

@@ -137,13 +137,18 @@ static const struct
 /* New BLR in 6.0 */
 	{"extract", extract}, {"current_date", zero},	/* 160 */
 	{"current_timestamp", zero}, {"current_time", zero},
-    /* These verbs were added in 6.0, primarily to support 64-bit integers */
 	{"post_arg", two},
 	{"exec_into", exec_into},
 	{"user_savepoint", user_savepoint},
+	
+	/* These are actually cursor operations added in Firebird 2.0 */
     {"divide2", two},
 	{"agg_total2", one},
-	{"agg_total_distinct2", one}, {"agg_average2", one}, {"agg_average_distinct2", one},	/* 170 */
+	
+	{"current_database", zero}, 
+	
+    /* These verbs were added in 6.0, primarily to support 64-bit integers, now obsolete */
+	{"agg_average2", one}, {"agg_average_distinct2", one},	/* 170 */
 	{"average2", two}, 
 	{"gen_id2", gen_id}, 
     {"set_generator2", gen_id},
@@ -156,6 +161,7 @@ static const struct
 	{"nullsfirst", zero},
 	{"writelock", zero},
 	{"nullslast", zero}, /* 180 */
+    {"current_database", zero},
 	{0, 0}
 };
 

src/jrd/blr.h

@@ -292,6 +292,7 @@
 #define blr_user_savepoint	(unsigned char)165
 #define blr_dcl_cursor		(unsigned char)166
 #define blr_cursor_stmt		(unsigned char)167
+#define blr_current_database (unsigned char)168
 
 /* These codes are actions for user-defined savepoints */
 

src/jrd/cmp.cpp

@@ -1696,6 +1696,14 @@ void CMP_get_desc(thread_db* tdbb, CompilerScratch* csb, jrd_nod* node, DSC * de
 		desc->dsc_flags = 0;
 		return;
 
+    case nod_current_database:
+		desc->dsc_dtype = dtype_text;
+		desc->dsc_ttype() = ttype_metadata;
+		desc->dsc_length = DATABASE_NAME_LENGTH;
+		desc->dsc_scale = 0;
+		desc->dsc_flags = 0;
+		return;
+
 	case nod_internal_info:
 		desc->dsc_dtype = dtype_long;
 		desc->dsc_length = sizeof(SLONG);
@@ -4942,6 +4950,7 @@ static jrd_nod* pass2(thread_db* tdbb, CompilerScratch* csb, jrd_nod* const node
 	case nod_null:
 	case nod_user_name:
     case nod_current_role:
+    case nod_current_database:
 	case nod_internal_info:
 	case nod_gen_id:
 	case nod_gen_id2:

src/jrd/constants.h

@@ -58,6 +58,10 @@ const ULONG MAX_COLUMN_SIZE	= 32767;	/* Bytes */
 
 const int USERNAME_LENGTH	= 31;	/* Bytes */
 
+// Maximum length of database file name. Since it is stored in system tables and
+// clumplet structures it is highly non-trivial to increase
+const int DATABASE_NAME_LENGTH	= 255;	/* Bytes */
+
 const size_t MAX_SQL_IDENTIFIER_SIZE = 32;
 const size_t MAX_SQL_IDENTIFIER_LEN = 31;
 typedef TEXT SqlIdentifier[MAX_SQL_IDENTIFIER_SIZE];

src/jrd/evl.cpp

@@ -19,7 +19,7 @@
  *
  * All Rights Reserved.
  * Contributor(s): ______________________________________.
-  * $Id: evl.cpp,v 1.121 2004-11-07 10:47:19 robocop Exp $ 
+  * $Id: evl.cpp,v 1.122 2004-11-11 05:37:44 skidder Exp $ 
  */
 
 /*
@@ -1015,6 +1015,20 @@ dsc* EVL_expr(thread_db* tdbb, jrd_nod* node)
 		}
 		return &impure->vlu_desc;
 
+	case nod_current_database:
+		impure->vlu_desc.dsc_dtype = dtype_text;
+		impure->vlu_desc.dsc_sub_type = 0;
+		impure->vlu_desc.dsc_scale = 0;
+		INTL_ASSIGN_TTYPE(&impure->vlu_desc, ttype_metadata);
+		
+		impure->vlu_desc.dsc_address =
+			(UCHAR*) tdbb->tdbb_database->dbb_database_name.c_str();
+			
+		impure->vlu_desc.dsc_length =
+			tdbb->tdbb_database->dbb_database_name.length();
+			
+		return &impure->vlu_desc;
+
 	case nod_extract:
 		{
 			impure = (impure_value*) ((SCHAR *) request + node->nod_impure);
@@ -1326,6 +1340,22 @@ bool EVL_field(jrd_rel* relation, Record* record, USHORT id, dsc* desc)
 						return true;
 					}
 					
+					if (temp_nod_type == nod_current_database)
+					{
+						thread_db* tdbb = NULL;
+						SET_TDBB(tdbb);
+						
+						desc->dsc_dtype    = dtype_text;
+						desc->dsc_sub_type = 0;
+						desc->dsc_scale    = 0;
+						INTL_ASSIGN_TTYPE(desc, ttype_metadata);
+						desc->dsc_address =
+							(UCHAR *) tdbb->tdbb_database->dbb_database_name.c_str();
+						desc->dsc_length =
+							tdbb->tdbb_database->dbb_database_name.length();
+						return true;
+					}
+
 					if (temp_nod_type == nod_current_date ||
 					    temp_nod_type == nod_current_time ||
 						temp_nod_type == nod_current_timestamp)

src/jrd/exe.h

@@ -508,6 +508,7 @@ const int e_extract_length	= 2;	/* Number of entries in nod_args */
 const int e_current_date_length		= 1;
 const int e_current_time_length		= 1;
 const int e_current_timestamp_length= 1;
+const int e_current_database_length = 1;
 
 const int e_dcl_cursor_number	= 0;
 const int e_dcl_cursor_rse		= 1;

src/jrd/jrd.cpp

@@ -570,13 +570,15 @@ ISC_STATUS GDS_ATTACH_DATABASE(ISC_STATUS*	user_status,
 	thread_db thd_context;
 	thread_db* tdbb = JRD_MAIN_set_thread_data(thd_context);
 
-/* If database name is not alias, check it against conf file */
+/* Check database against conf file. */
-	const vdnResult vdn = verify_database_name(expanded_filename, user_status);
+	const vdnResult vdn = verify_database_name(expanded_name, user_status);
 	if (!is_alias && vdn == vdnFail)
 	{
 		JRD_restore_context();
 		return user_status[1];
 	} 
+	else 
+	  user_status[0] = 0; // Clear status vector
 
 /* Unless we're already attached, do some initialization */
 
@@ -731,6 +733,18 @@ ISC_STATUS GDS_ATTACH_DATABASE(ISC_STATUS*	user_status,
 	{
 		first = true;
 		dbb->dbb_filename = expanded_name;
+		
+		// NS: Use alias as database ID only if accessing database using file name is not possible.
+		//
+		// This way we:
+		// 1. Ensure uniqueness of ID even in presence of multiple processes
+		// 2. Make sure that ID value can be used to connect back to database
+		//
+		if (is_alias && vdn == vdnFail)
+			dbb->dbb_database_name.assign(file_name, file_length ? file_length : strlen(file_name));
+		else
+			dbb->dbb_database_name = expanded_name;
+			
 		/* Extra LCK_init() done to keep the lock table until the
 		   database is shutdown() after the last detach. */
 		LCK_init(tdbb, LCK_OWNER_database);
@@ -1794,10 +1808,14 @@ ISC_STATUS GDS_CREATE_DATABASE(ISC_STATUS*	user_status,
 	}
 
 	// Check for DatabaseAccess
-	if (!is_alias && verify_database_name(expanded_name, user_status) == vdnFail) 
+	const vdnResult vdn = verify_database_name(expanded_name, user_status);
+	
+	if (!is_alias && vdn == vdnFail) 
 	{
 		ERR_punt();
 	} 
+	else 
+		user_status[0] = 0; // Clear status vector.
 
 	if (options.dpb_key) 
 	{
@@ -1989,6 +2007,17 @@ ISC_STATUS GDS_CREATE_DATABASE(ISC_STATUS*	user_status,
 	dbb->dbb_filename = expanded_name;
 #endif
 
+	// NS: Use alias as database ID only if accessing database using file name is not possible.
+	//
+	// This way we:
+	// 1. Ensure uniqueness of ID even in presence of multiple processes
+	// 2. Make sure that ID value can be used to connect back to database
+	//
+	if (is_alias && vdn == vdnFail)
+		dbb->dbb_database_name.assign(file_name, file_length ? file_length : strlen(file_name));
+	else
+		dbb->dbb_database_name = dbb->dbb_filename;
+
 #ifdef GOVERNOR
 	if (!options.dpb_sec_attach) {
 		if (JRD_max_users) {

src/jrd/jrd.h

@@ -207,6 +207,7 @@ public:
 	USHORT dbb_prefetch_pages;	/* prefetch pages per request */
 	Firebird::string dbb_spare_string;	/* random buffer */
 	Firebird::PathName dbb_filename;	/* filename string */
+	Firebird::PathName dbb_database_name;	/* database ID (file name or alias) */
 	Firebird::string dbb_encrypt_key;	/* encryption key */
 
 	JrdMemoryPool* dbb_permanent;
@@ -273,6 +274,7 @@ private:
 	:	dbb_modules(p),
 		dbb_spare_string(p),
 		dbb_filename(p),
+		dbb_database_name(p),
 		dbb_encrypt_key(p),
 		dbb_pools(1, p, type_dbb),
 		dbb_text_objects(p),

src/jrd/nod.h

@@ -207,3 +207,4 @@ NODE(nod_asn_list, asn_list, "")
 		  NODE(nod_dcl_cursor, declare_cursor, "DECLARE CURSOR")
 		  NODE(nod_cursor_stmt, cursor_stmt, "CURSOR STATEMENT")
 		  NODE(nod_equiv, equiv, " == ")
+          NODE(nod_current_database, current_database, "")

src/jrd/opt.cpp

@@ -2821,6 +2821,7 @@ static bool expression_possible_unknown(const jrd_nod* node)
 		case nod_argument:
 		case nod_current_date:
 		case nod_current_role:
+		case nod_current_database:
 		case nod_current_time:
 		case nod_current_timestamp:
 		case nod_gen_id:
@@ -2931,6 +2932,7 @@ static bool expression_contains_stream(const jrd_nod* node, UCHAR stream)
 		case nod_argument:
 		case nod_current_date:
 		case nod_current_role:
+		case nod_current_database:
 		case nod_current_time:
 		case nod_current_timestamp:
 		case nod_gen_id:
@@ -3251,6 +3253,7 @@ static bool expression_equal2(thread_db* tdbb, OptimizerBlk* opt,
 		case nod_null:
 		case nod_user_name:
 		case nod_current_role:
+		case nod_current_database:
 		case nod_current_time:
 		case nod_current_date:
 		case nod_current_timestamp:

src/jrd/par.cpp

@@ -2418,6 +2418,7 @@ static jrd_nod* parse(thread_db* tdbb, CompilerScratch* csb, USHORT expected,
 	case blr_agg_count:
 	case blr_user_name:
     case blr_current_role:
+    case blr_current_database:
 	case blr_current_date:
 	case blr_current_time:
 	case blr_current_timestamp:

src/misc/blrtable.cpp

@@ -226,6 +226,7 @@ static const VERB verbs[] =
 	PAIR(nod_current_role, blr_current_role, 1, 0, VALUE, VALUE),
 	PAIR(nod_dcl_cursor, blr_dcl_cursor, e_dcl_cursor_length, 0, STATEMENT, OTHER),
 	PAIR(nod_cursor_stmt, blr_cursor_stmt, e_cursor_stmt_length, 0, STATEMENT, OTHER),
+	PAIR(nod_current_database, blr_current_database, e_current_database_length, 0, VALUE, VALUE),
 	{0, NULL, NULL, NULL, NULL, NULL, NULL}
 };