1 //===-- Unittests for snprintf --------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "src/stdio/snprintf.h"
10 
11 #include "utils/UnitTest/Test.h"
12 
13 // The sprintf test cases cover testing the shared printf functionality, so
14 // these tests will focus on snprintf exclusive features.
15 
16 TEST(LlvmLibcSNPrintfTest, CutOff) {
17   char buff[64];
18   int written;
19 
20   written =
21       __llvm_libc::snprintf(buff, 16, "A simple string with no conversions.");
22   EXPECT_EQ(written, 36);
23   ASSERT_STREQ(buff, "A simple string");
24 
25   written = __llvm_libc::snprintf(buff, 5, "%s", "1234567890");
26   EXPECT_EQ(written, 10);
27   ASSERT_STREQ(buff, "1234");
28 
29   // passing null as the output pointer is allowed as long as buffsz is 0.
30   written = __llvm_libc::snprintf(nullptr, 0, "%s and more", "1234567890");
31   EXPECT_EQ(written, 19);
32 }
33 
34 TEST(LlvmLibcSNPrintfTest, NoCutOff) {
35   char buff[64];
36   int written;
37 
38   written =
39       __llvm_libc::snprintf(buff, 37, "A simple string with no conversions.");
40   EXPECT_EQ(written, 36);
41   ASSERT_STREQ(buff, "A simple string with no conversions.");
42 
43   written = __llvm_libc::snprintf(buff, 20, "%s", "1234567890");
44   EXPECT_EQ(written, 10);
45   ASSERT_STREQ(buff, "1234567890");
46 }
47