RDKB-63834: Add unit tests for empty config file detection and fprintf failure paths in persistence.c (#285)

* Initial plan

* Add unit tests for empty config file detection and fprintf failure in persistence.c

Co-authored-by: shibu-kv <89052442+shibu-kv@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: shibu-kv <89052442+shibu-kv@users.noreply.github.com>

Author: Copilot

.gitignore

@@ -0,0 +1,36 @@
+# Build system generated files
+Makefile
+Makefile.in
+aclocal.m4
+autom4te.cache/
+compile
+config.guess
+config.log
+config.status
+config.sub
+configure
+configure~
+depcomp
+install-sh
+libtool
+ltmain.sh
+missing
+m4/
+
+# Build artifacts
+*.o
+*.lo
+*.la
+*.a
+*.so
+*.bin
+*.deps/
+*.dirstamp
+.deps/
+.libs/
+
+# Source subdirectory build files
+source/**/Makefile
+source/**/Makefile.in
+source/**/*.deps/
+source/**/.libs/

source/test/mocks/FileioMock.cpp

@@ -473,6 +473,22 @@ extern "C" int fprintf(FILE* stream, const char* format, ...) {
     va_end(args);
     return result;
 }
+
+/* Intercept the FORTIFY_SOURCE-hardened variant of fprintf */
+extern "C" int __fprintf_chk(FILE* stream, int /*flag*/, const char* format, ...) {
+    va_list args;
+    va_start(args, format);
+    int result = -1;
+
+    if (g_fileIOMock) {
+        result = g_fileIOMock->fprintf(stream, format, args);
+    }
+    else {
+        result = vfprintf(stream, format, args);
+    }
+    va_end(args);
+    return result;
+}
 /*
 extern "C" CURLcode curl_easy_setopt(CURL *curl, CURLoption option, ...)
 {

source/test/utils/UtilsTest.cpp

@@ -50,6 +50,7 @@ using namespace std;
 using ::testing::_;
 using ::testing::Return;
 using ::testing::StrEq;
+using ::testing::Invoke;
 
 //Testing t2MtlsUtils
 TEST(GET_CERTS, MTLS_UTILS_NULL)
@@ -770,6 +771,49 @@ TEST_F(utilsTestFixture, FETCHLOCALCONFIGS_FUNC4)
     Vector_Destroy(configlist, free);
 }
 
+TEST_F(utilsTestFixture, FETCHLOCALCONFIGS_EMPTY_FILE)
+{
+    const char* path = "/opt/.t2persistentFolder/";
+    DIR *dir = (DIR*)0xffffffff;
+    Vector* configlist = NULL;
+    Vector_Create(&configlist);
+    struct dirent *entry = NULL;
+    entry = (struct dirent *)malloc(sizeof(struct dirent));
+    entry->d_type = DT_REG;
+    std::strncpy(entry->d_name, "TestProfile.json", sizeof(entry->d_name) - 1);
+    entry->d_name[sizeof(entry->d_name) - 1] = '\0';
+    EXPECT_CALL(*g_fileIOMock, opendir(_))
+           .Times(1)
+           .WillOnce(Return(dir));
+    EXPECT_CALL(*g_fileIOMock, readdir(_))
+           .Times(2)
+           .WillOnce(Return(entry))
+           .WillOnce(Return((struct dirent *)NULL));
+    EXPECT_CALL(*g_fileIOMock, open(_,_))
+           .Times(1)
+           .WillOnce(Return(1));
+    EXPECT_CALL(*g_fileIOMock, fstat(_,_))
+           .Times(1)
+           .WillOnce(Invoke([](int /*fd*/, struct stat* buf) -> int {
+               memset(buf, 0, sizeof(struct stat));
+               buf->st_size = 0;
+               return 0;
+           }));
+    EXPECT_CALL(*g_fileIOMock, close(_))
+           .Times(1)
+           .WillOnce(Return(0));
+    EXPECT_CALL(*g_systemMock, unlink(_))
+           .Times(1)
+           .WillOnce(Return(0));
+    EXPECT_CALL(*g_fileIOMock, closedir(_))
+           .Times(1)
+           .WillOnce(Return(0));
+    ASSERT_EQ(T2ERROR_SUCCESS, fetchLocalConfigs(path, configlist));
+    EXPECT_EQ(0, (int)Vector_Size(configlist));
+    Vector_Destroy(configlist, free);
+    free(entry);
+}
+
 #if defined (MTLS_FROM_ENV)
 TEST(GetMtlsCertsTest, ReturnsDynamicCertsWhenEnvSet) {
     setenv("XPKI", "1", 1);
@@ -915,28 +959,44 @@ TEST_F(utilsTestFixture, SAVECONFITOFILE1)
             .WillOnce(Return(mockfp));
      ASSERT_EQ(T2ERROR_FAILURE, saveConfigToFile(filepath, profilename, config));
 }
-/*
-TEST_F(utilsTestFixture, SAVECONFITOFILE2)
+TEST_F(utilsTestFixture, SAVECONFITOFILE_FPRINTF_FAILURE)
 {
-     const char* filepath = "/nvram/.t2reportprofiles";
-     const char* profilename = "Profile_1";
-     const char* config = "This is a config string";
-     FILE* mockfp = (FILE *)0xffffffff;
-
+    const char* filepath = "/nvram/.t2reportprofiles/";
+    const char* profilename = "Profile_1";
+    const char* config = "This is a config string";
+    FILE* mockfp = (FILE *)0xffffffff;
     EXPECT_CALL(*g_fileIOMock, fopen(_,_))
-	.Times(1)
-        .WillOnce(Return(mockfp));
+           .Times(1)
+           .WillOnce(Return(mockfp));
     EXPECT_CALL(*g_fileIOMock, fprintf(_,_,_))
-        .Times(1)
-        .WillOnce(Return(-1));
+           .Times(1)
+           .WillOnce(Return(-1));
     EXPECT_CALL(*g_fileIOMock, fclose(_))
-	.Times(1)
-        .WillOnce(Return(0));
-
-    EXPECT_EQ(saveConfigToFile(filepath, profilename, config), T2ERROR_SUCCESS);
+           .Times(1)
+           .WillOnce(Return(0));
+    EXPECT_CALL(*g_systemMock, unlink(_))
+           .Times(1)
+           .WillOnce(Return(0));
+    ASSERT_EQ(T2ERROR_FAILURE, saveConfigToFile(filepath, profilename, config));
+}
 
+TEST_F(utilsTestFixture, SAVECONFITOFILE_SUCCESS)
+{
+    const char* filepath = "/nvram/.t2reportprofiles/";
+    const char* profilename = "Profile_1";
+    const char* config = "This is a config string";
+    FILE* mockfp = (FILE *)0xffffffff;
+    EXPECT_CALL(*g_fileIOMock, fopen(_,_))
+           .Times(1)
+           .WillOnce(Return(mockfp));
+    EXPECT_CALL(*g_fileIOMock, fprintf(_,_,_))
+           .Times(1)
+           .WillOnce(Return((int)strlen(config)));
+    EXPECT_CALL(*g_fileIOMock, fclose(_))
+           .Times(1)
+           .WillOnce(Return(0));
+    ASSERT_EQ(T2ERROR_SUCCESS, saveConfigToFile(filepath, profilename, config));
 }
-*/
 TEST_F(utilsTestFixture, getDevicePropertyData)
 {