From e15684cb1477e2fac6170835ac9132443dc79970 Mon Sep 17 00:00:00 2001
From: akallabeth <akallabeth@posteo.net>
Date: Tue, 9 Feb 2021 15:48:20 +0100
Subject: [PATCH] Fixed a ConvertToUnicode issue and added a unit test

---
 .../libwinpr/crt/test/TestUnicodeConversion.c | 25 +++++++++++++++++++
 winpr/libwinpr/crt/unicode.c                  |  3 +--
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/winpr/libwinpr/crt/test/TestUnicodeConversion.c b/winpr/libwinpr/crt/test/TestUnicodeConversion.c
index 395be3200..e60b2b8bf 100644
--- a/winpr/libwinpr/crt/test/TestUnicodeConversion.c
+++ b/winpr/libwinpr/crt/test/TestUnicodeConversion.c
@@ -411,6 +411,31 @@ static BOOL test_ConvertToUnicode_wrapper(void)
 	int ii;
 	size_t i;
 
+	/* Test static string buffers of differing sizes */
+	{
+		char name[] = "someteststring";
+		const WCHAR cmp[] = { L's', L'o', L'm', L'e', L't', L'e', L's', L't',
+			                  L's', L't', L'r', L'i', L'n', L'g', 0 };
+		WCHAR xname[128] = { 0 };
+		LPWSTR aname = NULL;
+		LPWSTR wname = &xname[0];
+		const size_t len = strnlen(name, ARRAYSIZE(name) - 1);
+		ii = ConvertToUnicode(CP_UTF8, 0, name, len, &wname, ARRAYSIZE(xname));
+		if (ii != len)
+			goto fail;
+
+		if (memcmp(wname, cmp, sizeof(cmp)) != 0)
+			goto fail;
+
+		ii = ConvertToUnicode(CP_UTF8, 0, name, len, &aname, 0);
+		if (ii != len)
+			goto fail;
+		ii = memcmp(aname, cmp, sizeof(cmp));
+		free(aname);
+		if (ii != 0)
+			goto fail;
+	}
+
 	/* Test unterminated unicode string:
 	 * ConvertToUnicode must always null-terminate, even if the src string isn't
 	 */
diff --git a/winpr/libwinpr/crt/unicode.c b/winpr/libwinpr/crt/unicode.c
index 136df98c8..a49197971 100644
--- a/winpr/libwinpr/crt/unicode.c
+++ b/winpr/libwinpr/crt/unicode.c
@@ -429,9 +429,8 @@ int ConvertToUnicode(UINT CodePage, DWORD dwFlags, LPCSTR lpMultiByteStr, int cb
 		{
 			free(*lpWideCharStr);
 			*lpWideCharStr = NULL;
+			status = 0;
 		}
-
-		status = 0;
 	}
 
 	return status;