Álvaro Nieto : msvrct: Fix strncpy to fill the buffer.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: e3e12845572dce7b35660814c44dedf069de1dfb
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=e3e12845572dce7b35660814c4...

Author: Álvaro Nieto 
Date:   Tue Aug 13 21:47:20 2013 +0200

msvrct: Fix strncpy to fill the buffer.

---

dlls/msvcrt/string.c       |    2 ++
 dlls/msvcrt/tests/string.c |   31 +++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/dlls/msvcrt/string.c b/dlls/msvcrt/string.c
index c5d0e18..082029d 100644
--- a/dlls/msvcrt/string.c
+++ b/dlls/msvcrt/string.c
@@ -581,6 +581,8 @@ char* __cdecl MSVCRT_strncpy(char *dst, const char *src, MSVCRT_size_t len)
     for(i=0; i<len; i++)
         if((dst[i] = src[i]) == '\0') break;

+    while (i < len) dst[i++] = 0;
+
     return dst;
 }

diff --git a/dlls/msvcrt/tests/string.c b/dlls/msvcrt/tests/string.c
index 6e3f962..dc90b38 100644
--- a/dlls/msvcrt/tests/string.c
+++ b/dlls/msvcrt/tests/string.c
@@ -2574,6 +2574,36 @@ static void test_atoi(void)
     ok(r == 0, "atoi(4294967296) = %d\n", r);
 }

+static void test_strncpy(void)
+{
+#define TEST_STRNCPY_LEN 10
+    char *ret;
+    char dst[TEST_STRNCPY_LEN + 1];
+    char not_null_terminated[] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '0'};
+
+    /* strlen(src) > TEST_STRNCPY_LEN */
+    ret = strncpy(dst, "01234567890123456789", TEST_STRNCPY_LEN);
+    ok(ret == dst, "ret != dst\n");
+    ok(!strncmp(dst, "0123456789", TEST_STRNCPY_LEN), "dst != 0123456789\n");
+
+    /* without null-terminated */
+    ret = strncpy(dst, not_null_terminated, TEST_STRNCPY_LEN);
+    ok(ret == dst, "ret != dst\n");
+    ok(!strncmp(dst, "0123456789", TEST_STRNCPY_LEN), "dst != 0123456789\n");
+
+    /* strlen(src) < TEST_STRNCPY_LEN */
+    strcpy(dst, "0123456789");
+    ret = strncpy(dst, "012345", TEST_STRNCPY_LEN);
+    ok(ret == dst, "ret != dst\n");
+    ok(!strcmp(dst, "012345"), "dst != 012345\n");
+    ok(dst[TEST_STRNCPY_LEN - 1] == '\0', "dst[TEST_STRNCPY_LEN - 1] != 0\n");
+
+    /* strlen(src) == TEST_STRNCPY_LEN */
+    ret = strncpy(dst, "0123456789", TEST_STRNCPY_LEN);
+    ok(ret == dst, "ret != dst\n");
+    ok(!strncmp(dst, "0123456789", TEST_STRNCPY_LEN), "dst != 0123456789\n");
+}
+
 START_TEST(string)
 {
     char mem[100];
@@ -2675,4 +2705,5 @@ START_TEST(string)
     test__stricmp();
     test__wcstoi64();
     test_atoi();
+    test_strncpy();
 }