Implement well-defined handling of unrecoverable errors

Plus the addition of some convenience CRASH_* error macros.
Plus transient avoidance of the flood of warnings emitted by Clang when checking 'this' for NULL.
Plus explanation about the do-while(0) loop in some error macros.
This commit is contained in:
Pedro J. Estébanez 2017-05-26 21:11:16 +02:00
parent 9fa4f1c54c
commit 211c451890
8 changed files with 76 additions and 45 deletions

View file

@ -403,14 +403,9 @@ public:
if (p_to < 0) {
p_to = size() + p_to;
}
if (p_from < 0 || p_from >= size()) {
PoolVector<T> &aux = *((PoolVector<T> *)0); // nullreturn
ERR_FAIL_COND_V(p_from < 0 || p_from >= size(), aux)
}
if (p_to < 0 || p_to >= size()) {
PoolVector<T> &aux = *((PoolVector<T> *)0); // nullreturn
ERR_FAIL_COND_V(p_to < 0 || p_to >= size(), aux)
}
CRASH_BAD_INDEX(p_from, size());
CRASH_BAD_INDEX(p_to, size());
PoolVector<T> slice;
int span = 1 + p_to - p_from;
@ -500,13 +495,9 @@ void PoolVector<T>::push_back(const T &p_val) {
template <class T>
const T PoolVector<T>::operator[](int p_index) const {
if (p_index < 0 || p_index >= size()) {
T &aux = *((T *)0); //nullreturn
ERR_FAIL_COND_V(p_index < 0 || p_index >= size(), aux);
}
CRASH_BAD_INDEX(p_index, size());
Read r = read();
return r[p_index];
}

View file

@ -115,6 +115,19 @@ extern bool _err_error_exists;
#define FUNCTION_STR __FUNCTION__
#endif
// Don't use this directly; instead, use any of the CRASH_* macros
#ifdef _MSC_VER
#define GENERATE_TRAP \
__debugbreak(); \
/* Avoid warning about control paths */ \
for (;;) { \
}
#else
#define GENERATE_TRAP __builtin_trap();
#endif
// (*): See https://stackoverflow.com/questions/257418/do-while-0-what-is-it-good-for
#define ERR_FAIL_INDEX(m_index, m_size) \
do { \
if ((m_index) < 0 || (m_index) >= (m_size)) { \
@ -122,12 +135,12 @@ extern bool _err_error_exists;
return; \
} else \
_err_error_exists = false; \
} while (0);
} while (0); // (*)
/** An index has failed if m_index<0 or m_index >=m_size, the function exists.
* This function returns an error value, if returning Error, please select the most
* appropriate error condition from error_macros.h
*/
* This function returns an error value, if returning Error, please select the most
* appropriate error condition from error_macros.h
*/
#define ERR_FAIL_INDEX_V(m_index, m_size, m_retval) \
do { \
@ -136,7 +149,18 @@ extern bool _err_error_exists;
return m_retval; \
} else \
_err_error_exists = false; \
} while (0);
} while (0); // (*)
/** Use this one if there is no sensible fallback, that is, the error is unrecoverable.
* We'll return a null reference and try to keep running.
*/
#define CRASH_BAD_INDEX(m_index, m_size) \
do { \
if ((m_index) < 0 || (m_index) >= (m_size)) { \
_err_print_error(FUNCTION_STR, __FILE__, __LINE__, "FATAL: Index " _STR(m_index) " out of size (" _STR(m_size) ")."); \
GENERATE_TRAP \
} \
} while (0); // (*)
/** An error condition happened (m_cond tested true) (WARNING this is the opposite as assert().
* the function will exit.
@ -173,6 +197,17 @@ extern bool _err_error_exists;
_err_error_exists = false; \
}
/** Use this one if there is no sensible fallback, that is, the error is unrecoverable.
*/
#define CRASH_COND(m_cond) \
{ \
if (m_cond) { \
_err_print_error(FUNCTION_STR, __FILE__, __LINE__, "FATAL: Condition ' " _STR(m_cond) " ' is true."); \
GENERATE_TRAP \
} \
}
/** An error condition happened (m_cond tested true) (WARNING this is the opposite as assert().
* the function will exit.
* This function returns an error value, if returning Error, please select the most
@ -234,6 +269,15 @@ extern bool _err_error_exists;
return m_value; \
}
/** Use this one if there is no sensible fallback, that is, the error is unrecoverable.
*/
#define CRASH_NOW() \
{ \
_err_print_error(FUNCTION_STR, __FILE__, __LINE__, "FATAL: Method/Function Failed."); \
GENERATE_TRAP \
}
/** Print an error string.
*/

View file

@ -473,8 +473,7 @@ public:
if (!e) {
e = create_entry(p_key);
if (!e)
return *(TData *)NULL; /* panic! */
CRASH_COND(!e);
check_hash_table(); // perform mantenience routine
}

View file

@ -398,10 +398,7 @@ public:
T &operator[](int p_index) {
if (p_index < 0 || p_index >= size()) {
T &aux = *((T *)0); //nullreturn
ERR_FAIL_COND_V(p_index < 0 || p_index >= size(), aux);
}
CRASH_BAD_INDEX(p_index, size());
Element *I = front();
int c = 0;
@ -415,15 +412,12 @@ public:
c++;
}
ERR_FAIL_V(*((T *)0)); // bug!!
CRASH_NOW(); // bug!!
}
const T &operator[](int p_index) const {
if (p_index < 0 || p_index >= size()) {
T &aux = *((T *)0); //nullreturn
ERR_FAIL_COND_V(p_index < 0 || p_index >= size(), aux);
}
CRASH_BAD_INDEX(p_index, size());
const Element *I = front();
int c = 0;
@ -437,7 +431,7 @@ public:
c++;
}
ERR_FAIL_V(*((T *)0)); // bug!
CRASH_NOW(); // bug!!
}
void move_to_back(Element *p_I) {

View file

@ -599,9 +599,9 @@ public:
const V &operator[](const K &p_key) const {
ERR_FAIL_COND_V(!_data._root, *(V *)NULL); // crash on purpose
CRASH_COND(!_data._root);
const Element *e = find(p_key);
ERR_FAIL_COND_V(!e, *(V *)NULL); // crash on purpose
CRASH_COND(!e);
return e->_value;
}
V &operator[](const K &p_key) {
@ -613,7 +613,7 @@ public:
if (!e)
e = insert(p_key, V());
ERR_FAIL_COND_V(!e, *(V *)NULL); // crash on purpose
CRASH_COND(!e);
return e->_value;
}

View file

@ -531,6 +531,12 @@ public:
void add_change_receptor(Object *p_receptor);
void remove_change_receptor(Object *p_receptor);
// TODO: ensure 'this' is never NULL since it's UB, but by now, avoid warning flood
#ifdef __clang__
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wundefined-bool-conversion"
#endif
template <class T>
T *cast_to() {
@ -561,6 +567,10 @@ public:
#endif
}
#ifdef __clang__
#pragma clang diagnostic pop
#endif
enum {
NOTIFICATION_POSTINITIALIZE = 0,

View file

@ -134,10 +134,7 @@ public:
inline T &operator[](int p_index) {
if (p_index < 0 || p_index >= size()) {
T &aux = *((T *)0); //nullreturn
ERR_FAIL_COND_V(p_index < 0 || p_index >= size(), aux);
}
CRASH_BAD_INDEX(p_index, size());
_copy_on_write(); // wants to write, so copy on write.
@ -146,10 +143,8 @@ public:
inline const T &operator[](int p_index) const {
if (p_index < 0 || p_index >= size()) {
const T &aux = *((T *)0); //nullreturn
ERR_FAIL_COND_V(p_index < 0 || p_index >= size(), aux);
}
CRASH_BAD_INDEX(p_index, size());
// no cow needed, since it's reading
return _get_data()[p_index];
}

View file

@ -180,10 +180,8 @@ public:
inline const V &operator[](const T &p_key) const {
int pos = _find_exact(p_key);
if (pos < 0) {
const T &aux = *((T *)0); //nullreturn
ERR_FAIL_COND_V(pos < 1, aux);
}
CRASH_COND(pos < 0);
return _data[pos].value;
}