Fix random UT failures on PosixFile (nasa#2862)

* Fix Random UT Failure: PosixFile (nasa#2835)
 * Fix UT failing FinalizeCrc test when crc calculation miss match.
   Miss match due to file crc and shadow being out of sync when
   both are not reinialized at the same time.

 * Update File::open in File.ccp to match shadow operation in
   FileRules.cpp to only reset crc when status is OP_OK.

 * Update FileRules.cpp to print out rule name during test.

 * Remove changing file mode in shadow_open() in FileRules.cpp to
   OPEN_NO_MODE when status is not OP_OK.

* Fix Random UT Failure: PosixFile (nasa#2835)
 * Fix additional issue where randomly generate file name may be
   too large for POSIX.

* Fix Random UT Failure: PosixFile (nasa#2835)
 * Fix preallocate test from picking 0 for length, which causes
   unintentional error in preallocate cmd.
 * Fix seek() in SyntheticFileSystem and assert_file_seek() to allow
   for offset being 0.

Os/Posix/test/ut/PosixFileTests.cpp

@@ -33,8 +33,8 @@ bool check_permissions(const char* path, int permission) {
 //!
 std::shared_ptr<std::string> get_test_filename(bool random) {
     const char* filename = TEST_FILE;
-    char full_buffer[PATH_MAX];
-    char buffer[PATH_MAX - sizeof(BASE_PATH)];
+    char full_buffer[_POSIX_PATH_MAX];
+    char buffer[_POSIX_PATH_MAX - sizeof(BASE_PATH)];
     // When random, select random characters
     if (random) {
         filename = buffer;
@@ -47,7 +47,7 @@ std::shared_ptr<std::string> get_test_filename(bool random) {
         }
         buffer[i] = 0; // Terminate random string
     }
-    (void) snprintf(full_buffer, PATH_MAX, "%s/%s", BASE_PATH, filename);
+    (void) snprintf(full_buffer, _POSIX_PATH_MAX, "%s/%s", BASE_PATH, filename);
     // Create a shared pointer wrapping our filename buffer
     std::shared_ptr<std::string> pointer(new std::string(full_buffer), std::default_delete<std::string>());
     return pointer;

Os/test/ut/file/FileRules.cpp

@@ -231,7 +231,7 @@ void Os::Test::File::Tester::assert_file_seek(const FwSignedSizeType original_po
     ASSERT_EQ(this->m_shadow.position(shadow_position), Os::File::Status::OP_OK);
 
     const FwSignedSizeType expected_offset = (absolute) ? seek_desired : (original_position + seek_desired);
-    if (expected_offset > 0) {
+    if (expected_offset >= 0) {
         ASSERT_EQ(new_position, expected_offset);
     } else {
         ASSERT_EQ(new_position, original_position);
@@ -497,7 +497,7 @@ void Os::Test::File::Tester::Preallocate::action(
     state.assert_file_consistent();
     FileState original_file_state = state.current_file_state();
     FwSignedSizeType offset = static_cast<FwSignedSizeType>(STest::Pick::lowerUpper(0, FILE_DATA_MAXIMUM));
-    FwSignedSizeType length = static_cast<FwSignedSizeType>(STest::Pick::lowerUpper(0, FILE_DATA_MAXIMUM));
+    FwSignedSizeType length = static_cast<FwSignedSizeType>(STest::Pick::lowerUpper(1, FILE_DATA_MAXIMUM));
     Os::File::Status status = state.m_file.preallocate(offset, length);
     ASSERT_EQ(Os::File::Status::OP_OK, status);
     state.shadow_preallocate(offset, length);

Os/test/ut/file/SyntheticFileSystem.cpp

@@ -191,7 +191,7 @@ Os::File::Status SyntheticFile::seek(const FwSignedSizeType offset, const SeekTy
         status = Os::File::Status::NOT_OPENED;
     } else {
         FwSignedSizeType new_offset = (absolute) ? offset : (offset + this->m_data->m_pointer);
-        if (new_offset > 0) {
+        if (new_offset >= 0) {
             this->m_data->m_pointer = new_offset;
         } else {
             status = Os::File::Status::INVALID_ARGUMENT;