[Tarantool-patches] [PATCH v1 1/1] sql: limit blob size during CAST AS INTEGER

[imeevma at tarantool.org]

This patch limits the number of decoded bytes during CAST from
BLOB to INTEGER according to the specified BLOB size.

Closes #4766
---
https://github.com/tarantool/tarantool/issues/4766
https://github.com/tarantool/tarantool/tree/imeevma/gh-4766-fix-blob-size-for-cast

 src/box/sql/util.c         | 13 ++++++++++---
 test/sql-tap/cast.test.lua | 32 +++++++++++++++++++++++++++++++-
 2 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/src/box/sql/util.c b/src/box/sql/util.c
index f908e9c..8f70ce6 100644
--- a/src/box/sql/util.c
+++ b/src/box/sql/util.c
@@ -467,14 +467,21 @@ sql_atoi64(const char *z, int64_t *val, bool *is_neg, int length)
 	if (*z == '-')
 		*is_neg = true;
 
+	/*
+	 * BLOB data may not end with '\0'. This leads to an error
+	 * in the strtoll() and strtoull() functions. To fix this,
+	 * let's copy the value for decoding into static memory
+	 * and add '\0' to it.
+	 */
+	const char *str_value = tt_cstr(z, length);
 	char *end = NULL;
 	errno = 0;
-	if (*z == '-') {
+	if (*str_value == '-') {
 		*is_neg = true;
-		*val = strtoll(z, &end, 10);
+		*val = strtoll(str_value, &end, 10);
 	} else {
 		*is_neg = false;
-		uint64_t u_val = strtoull(z, &end, 10);
+		uint64_t u_val = strtoull(str_value, &end, 10);
 		*val = u_val;
 	}
 	/* Overflow and underflow errors. */
diff --git a/test/sql-tap/cast.test.lua b/test/sql-tap/cast.test.lua
index 9c937a0..a579f24 100755
--- a/test/sql-tap/cast.test.lua
+++ b/test/sql-tap/cast.test.lua
@@ -1,6 +1,6 @@
 #!/usr/bin/env tarantool
 test = require("sqltester")
-test:plan(85)
+test:plan(87)
 
 --!./tcltestrunner.lua
 -- 2005 June 25
@@ -905,4 +905,34 @@ test:do_execsql_test(
         -- </cast-5.1>
     })
 
+--
+-- gh-4766: Make sure that a blob as part of a tuple can be cast
+-- to NUMBER, INTEGER and UNSIGNED.
+--
+test:do_execsql_test(
+    "cast-6.1",
+    [[
+        CREATE TABLE t (a VARBINARY PRIMARY KEY);
+        INSERT INTO t VALUES (X'33'), (X'372020202020');
+        SELECT a, CAST(a AS NUMBER), CAST(a AS INTEGER), CAST(a AS UNSIGNED) FROM t;
+        DROP TABLE t;
+    ]], {
+        -- <cast-6.1>
+        '3', 3, 3, 3, '7     ', 7, 7, 7
+        -- </cast-6.1>
+    })
+
+test:do_execsql_test(
+    "cast-6.2",
+    [[
+        CREATE TABLE t (a VARBINARY PRIMARY KEY, i INT);
+        INSERT INTO t VALUES (X'33', 1);
+        SELECT a, CAST(a AS NUMBER), CAST(a AS INTEGER), CAST(a AS UNSIGNED) FROM t;
+        DROP TABLE t;
+    ]], {
+        -- <cast-6.2>
+        '3', 3, 3, 3
+        -- </cast-6.2>
+    })
+
 test:finish_test()
-- 
2.7.4