[tarantool-patches] [PATCH v2 5/6] sql: 'PRAGMA' result in Tarantool format

[imeevma@tarantool.org]

Currently, box.sql.execute('PRAGMA') returns nothing but it prints
some information on stdout. This isn't right. This patch makes
the command to return result in Tarantool format.

Part of #3832
---
 src/box/sql/pragma.c   | 83 +++++++++++++++++++++++++++++---------------------
 test/sql/misc.result   | 12 ++++++++
 test/sql/misc.test.lua |  5 +++
 3 files changed, 65 insertions(+), 35 deletions(-)

diff --git a/src/box/sql/pragma.c b/src/box/sql/pragma.c
index 9390f6f..fc87976 100644
--- a/src/box/sql/pragma.c
+++ b/src/box/sql/pragma.c
@@ -168,48 +168,61 @@ pragmaLocate(const char *zName)
 	return lwr > upr ? 0 : &aPragmaName[mid];
 }
 
-#ifdef PRINT_PRAGMA
-#undef PRINT_PRAGMA
-#endif
-#define PRINT_PRAGMA(pragma_name, pragma_flag) do {			       \
-	int nCoolSpaces = 30 - strlen(pragma_name);			       \
-	if (user_session->sql_flags & (pragma_flag)) {			       \
-		printf("%s %*c --  [true] \n", pragma_name, nCoolSpaces, ' '); \
-	} else {							       \
-		printf("%s %*c --  [false] \n", pragma_name, nCoolSpaces, ' ');\
-	}								       \
-} while (0)
-
-#define PRINT_STR_PRAGMA(pragma_name, str_value) do {			       \
-	int nCoolSpaces = 30 - strlen(pragma_name);			       \
-	printf("%s %*c --  '%s' \n", pragma_name, nCoolSpaces, ' ', str_value);\
-} while (0)
-
 static void
-printActivePragmas(struct session *user_session)
+sql_pragma_active_pragmas(struct Parse *parse)
 {
-	int i;
-	for (i = 0; i < ArraySize(aPragmaName); ++i) {
+	struct Vdbe *v = sqlite3GetVdbe(parse);
+	struct session *user_session = current_session();
+
+	sqlite3VdbeSetNumCols(v, 2);
+	sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "pragma_name", SQLITE_STATIC);
+	sqlite3VdbeSetColName(v, 0, COLNAME_DECLTYPE, "TEXT", SQLITE_STATIC);
+	sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "pragma_value",
+			      SQLITE_STATIC);
+	sqlite3VdbeSetColName(v, 1, COLNAME_DECLTYPE, "TEXT", SQLITE_STATIC);
+
+	parse->nMem = 2;
+	for (int i = 0; i < ArraySize(aPragmaName); ++i) {
+		sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, aPragmaName[i].zName,
+				  0);
 		switch (aPragmaName[i].ePragTyp) {
-			case PragTyp_FLAG:
-				PRINT_PRAGMA(aPragmaName[i].zName, aPragmaName[i].iArg);
+			case PragTyp_PARSER_TRACE:
+			case PragTyp_CASE_SENSITIVE_LIKE:
+			case PragTyp_FLAG: {
+				const char *value;
+				if ((user_session->sql_flags &
+				     aPragmaName[i].iArg) != 0)
+					value = "true";
+				else
+					value = "false";
+				sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, value,
+						  0);
 				break;
+			}
 			case PragTyp_DEFAULT_ENGINE: {
-				const char *engine_name =
-					sql_storage_engine_strs[
-						current_session()->
-							sql_default_engine];
-				PRINT_STR_PRAGMA(aPragmaName[i].zName,
-						 engine_name);
+				const char *value = sql_storage_engine_strs[
+					user_session->sql_default_engine];
+				sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, value,
+						  0);
 				break;
 			}
+			case PragTyp_BUSY_TIMEOUT: {
+				int value = parse->db->busyTimeout;
+				sqlite3VdbeAddOp2(v, OP_Integer, value, 2);
+				sqlite3VdbeAddOp2(v, OP_Cast, 2, AFFINITY_TEXT);
+				break;
+			}
+			case PragTyp_COMPOUND_SELECT_LIMIT: {
+				int value = sqlite3_limit(parse->db,
+					SQL_LIMIT_COMPOUND_SELECT, -1);
+				sqlite3VdbeAddOp2(v, OP_Integer, value, 2);
+				sqlite3VdbeAddOp2(v, OP_Cast, 2, AFFINITY_TEXT);
+				break;
+			}
+			default:
+				sqlite3VdbeAddOp2(v, OP_Null, 0, 2);
 		}
-	}
-
-	printf("Other available pragmas: \n");
-	for (i = 0; i < ArraySize(aPragmaName); ++i) {
-		if (aPragmaName[i].ePragTyp != PragTyp_FLAG)
-			printf("-- %s \n", aPragmaName[i].zName);
+		sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
 	}
 }
 
@@ -440,7 +453,7 @@ sqlite3Pragma(Parse * pParse, Token * pId,	/* First part of [schema.]id field */
 
 	zLeft = sqlite3NameFromToken(db, pId);
 	if (!zLeft) {
-		printActivePragmas(user_session);
+		sql_pragma_active_pragmas(pParse);
 		return;
 	}
 
diff --git a/test/sql/misc.result b/test/sql/misc.result
index f1031f7..758734c 100644
--- a/test/sql/misc.result
+++ b/test/sql/misc.result
@@ -57,3 +57,15 @@ result[1][1] == 0 or result[1][1] == 1
 box.sql.execute('PRAGMA case_sensitive_like = '.. result[1][1])
 ---
 ...
+-- Make command "PRAGMA" return result in Tarantool format.
+res = box.sql.execute('PRAGMA')
+---
+...
+#res > 0
+---
+- true
+...
+res[1][1]
+---
+- busy_timeout
+...
diff --git a/test/sql/misc.test.lua b/test/sql/misc.test.lua
index 5952035..1c0dd07 100644
--- a/test/sql/misc.test.lua
+++ b/test/sql/misc.test.lua
@@ -24,3 +24,8 @@ result[1][1] == 0 or result[1][1] == 1
 -- Check that "PRAGMA case_sensitive_like" returns nothing if
 -- called with parameter.
 box.sql.execute('PRAGMA case_sensitive_like = '.. result[1][1])
+
+-- Make command "PRAGMA" return result in Tarantool format.
+res = box.sql.execute('PRAGMA')
+#res > 0
+res[1][1]
-- 
2.7.4