Add string utility functions.

These are used by the coming-soon vboot wrapper (vboot_api_kernel) to
display debug information when Tab is pressed at a BIOS screen.

BUG=chromium-os:17035
TEST=make && make runtests (runs new test!)

Change-Id: I4893f31e9333f4e9d458a6e347213eef22f770cd
Reviewed-on: http://gerrit.chromium.org/gerrit/3759
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
Tested-by: Randall Spangler <rspangler@chromium.org>

2 files changed, 123 insertions, 0 deletions

diff --git a/tests/Makefile b/tests/Makefile
index e97bbe11..e2a4af53 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -15,6 +15,7 @@ TEST_NAMES = cgptlib_test \
 	     rsa_verify_benchmark \
 	     sha_benchmark \
 	     sha_tests \
+	     utility_string_tests \
 	     vboot_common_tests \
 	     vboot_common2_tests \
 	     vboot_common3_tests \
@@ -90,6 +91,7 @@ runcryptotests:
 # Run other misc tests
 runmisctests:
 	./run_vbutil_tests.sh
+	${BUILD_ROOT}/utility_string_tests
 
 #This will exercise vbutil_kernel and vbutil_firmware
 runfuzztests:
diff --git a/tests/utility_string_tests.c b/tests/utility_string_tests.c
new file mode 100644
index 00000000..91f57146
--- /dev/null
+++ b/tests/utility_string_tests.c
@@ -0,0 +1,121 @@
+/* Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Tests for string utility functions.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "test_common.h"
+#include "utility.h"
+#include "vboot_common.h"
+
+
+/* Test string concatenation */
+static void StrncatTest(void) {
+  char dest[128];
+
+  /* Null inputs */
+  TEST_EQ(0, Strncat(dest, NULL, sizeof(dest)), "Strncat('', null)");
+  TEST_EQ(0, Strncat(NULL, "Hey!", sizeof(dest)), "Strncat(null, '')");
+
+  /* Empty <-- empty */
+  *dest = 0;
+  TEST_EQ(0, Strncat(dest, "", sizeof(dest)), "Strncat('', '')");
+  TEST_EQ(0, strcmp(dest, ""), "Strncat('', '') result");
+
+  /* Nonempty <-- empty */
+  strcpy(dest, "Bob");
+  TEST_EQ(3, Strncat(dest, "", sizeof(dest)), "Strncat(B, '')");
+  TEST_EQ(0, strcmp(dest, "Bob"), "Strncat(B, '') result");
+
+  /* Empty <-- nonempty */
+  *dest = 0;
+  TEST_EQ(5, Strncat(dest, "Alice", sizeof(dest)), "Strncat('', A)");
+  TEST_EQ(0, strcmp(dest, "Alice"), "Strncat('', A) result");
+
+  /* Nonempty <-- nonempty */
+  strcpy(dest, "Tigre");
+  TEST_EQ(10, Strncat(dest, "Bunny", sizeof(dest)), "Strncat(T, B)");
+  TEST_EQ(0, strcmp(dest, "TigreBunny"), "Strncat(T, B) result");
+
+  /* Test clipping */
+  strcpy(dest, "YesI");
+  TEST_EQ(7, Strncat(dest, "Can't", 8), "Strncat(Y, over)");
+  TEST_EQ(0, strcmp(dest, "YesICan"), "Strncat(Y, over) result");
+
+  /* Test clipping if dest already overflows its claimed length */
+  strcpy(dest, "BudgetDeficit");
+  TEST_EQ(6, Strncat(dest, "Spending", 7), "Strncat(over, over)");
+  TEST_EQ(0, strcmp(dest, "Budget"), "Strncat(over, over) result");
+}
+
+
+static void TestU64ToS(uint64_t value, uint32_t radix, uint32_t zero_pad_width,
+                       const char *expect) {
+  char dest[UINT64_TO_STRING_MAX];
+
+  TEST_EQ(strlen(expect),
+          Uint64ToString(dest, sizeof(dest), value, radix, zero_pad_width),
+          "Uint64ToString");
+  printf("Uint64ToString expect %s got %s\n", expect, dest);
+  TEST_EQ(0, strcmp(dest, expect), "Uint64ToString result");
+}
+
+
+/* Test uint64 to string conversion */
+static void Uint64ToStringTest(void) {
+  char dest[UINT64_TO_STRING_MAX];
+
+  /* Test invalid inputs */
+  TEST_EQ(0, Uint64ToString(NULL, 8, 123, 10, 8), "Uint64ToString null dest");
+  TestU64ToS(0, 1, 0, "");
+  TestU64ToS(0, 37, 0, "");
+
+  /* Binary */
+  TestU64ToS(0, 2, 0, "0");
+  TestU64ToS(0x9A, 2, 0, "10011010");
+  TestU64ToS(0x71, 2, 12, "000001110001");
+  TestU64ToS(
+      ~UINT64_C(0), 2, 0,
+      "1111111111111111111111111111111111111111111111111111111111111111");
+
+  /* Decimal */
+  TestU64ToS(0, 10, 0, "0");
+  TestU64ToS(12345, 10, 0, "12345");
+  TestU64ToS(67890, 10, 8, "00067890");
+  TestU64ToS(~UINT64_C(0), 10, 0, "18446744073709551615");
+
+  /* Hex */
+  TestU64ToS(0, 16, 0, "0");
+  TestU64ToS(0x12345678, 16, 0, "12345678");
+  TestU64ToS(0x9ABCDEF, 16, 8, "09abcdef");
+  TestU64ToS(~UINT64_C(0), 16, 0, "ffffffffffffffff");
+
+  /* Zero pad corner cases */
+  /* Don't pad if over length */
+  TestU64ToS(0x1234567890, 16, 8, "1234567890");
+  /* Fail if padding won't fit in buffer */
+  TEST_EQ(0, Uint64ToString(dest, 8, 123, 10, 8), "Uint64ToString bad pad");
+  TEST_EQ(0, strcmp(dest, ""), "Uint64ToString bad pad result");
+
+}
+
+
+/* disable MSVC warnings on unused arguments */
+__pragma(warning (disable: 4100))
+
+int main(int argc, char* argv[]) {
+  int error_code = 0;
+
+  StrncatTest();
+  Uint64ToStringTest();
+
+  if (!gTestSuccess)
+    error_code = 255;
+
+  return error_code;
+}