Commit b1133996 authored by Nick Mathewson's avatar Nick Mathewson 🐛
Browse files

Merge branch 'bug27709_029' into maint-0.2.9

parents 717507e3 5e582c7f
o Minor bugfixes (code safety):
- Rewrite our assertion macros so that they no longer suppress
the compiler's -Wparentheses warnings on their inputs. Fixes bug 27709;
bugfix on 0.0.6.
......@@ -29,6 +29,35 @@
#error "Sorry; we don't support building with NDEBUG."
#endif
#if defined(TOR_UNIT_TESTS) && defined(__GNUC__)
/* We define this GCC macro as a replacement for PREDICT_UNLIKELY() in this
* header, so that in our unit test builds, we'll get compiler warnings about
* stuff like tor_assert(n = 5).
*
* The key here is that (e) is wrapped in exactly one layer of parentheses,
* and then passed right to a conditional. If you do anything else to the
* expression here, or introduce any more parentheses, the compiler won't
* help you.
*
* We only do this for the unit-test build case because it interferes with
* the likely-branch labeling. Note below that in the other case, we define
* these macros to just be synonyms for PREDICT_(UN)LIKELY.
*/
#define ASSERT_PREDICT_UNLIKELY_(e) \
({ \
int tor__assert_tmp_value__; \
if (e) \
tor__assert_tmp_value__ = 1; \
else \
tor__assert_tmp_value__ = 0; \
tor__assert_tmp_value__; \
})
#define ASSERT_PREDICT_LIKELY_(e) ASSERT_PREDICT_UNLIKELY_(e)
#else
#define ASSERT_PREDICT_UNLIKELY_(e) PREDICT_UNLIKELY(e)
#define ASSERT_PREDICT_LIKELY_(e) PREDICT_LIKELY(e)
#endif
/* Sometimes we don't want to use assertions during branch coverage tests; it
* leads to tons of unreached branches which in reality are only assertions we
* didn't hit. */
......@@ -40,7 +69,8 @@
/** Like assert(3), but send assertion failures to the log as well as to
* stderr. */
#define tor_assert(expr) STMT_BEGIN \
if (PREDICT_UNLIKELY(!(expr))) { \
if (ASSERT_PREDICT_LIKELY_(expr)) { \
} else { \
tor_assertion_failed_(SHORT_FILE__, __LINE__, __func__, #expr); \
abort(); \
} STMT_END
......@@ -77,7 +107,7 @@
#define tor_assert_nonfatal_unreached_once() tor_assert(0)
#define tor_assert_nonfatal_once(cond) tor_assert((cond))
#define BUG(cond) \
(PREDICT_UNLIKELY(cond) ? \
(ASSERT_PREDICT_UNLIKELY_(cond) ? \
(tor_assertion_failed_(SHORT_FILE__,__LINE__,__func__,"!("#cond")"), \
abort(), 1) \
: 0)
......@@ -86,14 +116,15 @@
#define tor_assert_nonfatal(cond) ((void)(cond))
#define tor_assert_nonfatal_unreached_once() STMT_NIL
#define tor_assert_nonfatal_once(cond) ((void)(cond))
#define BUG(cond) (PREDICT_UNLIKELY(cond) ? 1 : 0)
#define BUG(cond) (ASSERT_PREDICT_UNLIKELY_(cond) ? 1 : 0)
#else /* Normal case, !ALL_BUGS_ARE_FATAL, !DISABLE_ASSERTS_IN_UNIT_TESTS */
#define tor_assert_nonfatal_unreached() STMT_BEGIN \
tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, NULL, 0); \
STMT_END
#define tor_assert_nonfatal(cond) STMT_BEGIN \
if (PREDICT_UNLIKELY(!(cond))) { \
tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, #cond, 0); \
if (ASSERT_PREDICT_LIKELY_(cond)) { \
} else { \
tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, #cond, 0); \
} \
STMT_END
#define tor_assert_nonfatal_unreached_once() STMT_BEGIN \
......@@ -105,13 +136,14 @@
STMT_END
#define tor_assert_nonfatal_once(cond) STMT_BEGIN \
static int warning_logged__ = 0; \
if (!warning_logged__ && PREDICT_UNLIKELY(!(cond))) { \
if (ASSERT_PREDICT_LIKELY_(cond)) { \
} else if (!warning_logged__) { \
warning_logged__ = 1; \
tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, #cond, 1); \
} \
STMT_END
#define BUG(cond) \
(PREDICT_UNLIKELY(cond) ? \
(ASSERT_PREDICT_UNLIKELY_(cond) ? \
(tor_bug_occurred_(SHORT_FILE__,__LINE__,__func__,"!("#cond")",0), 1) \
: 0)
#endif
......@@ -120,17 +152,17 @@
#define IF_BUG_ONCE__(cond,var) \
if (( { \
static int var = 0; \
int bool_result = (cond); \
if (PREDICT_UNLIKELY(bool_result) && !var) { \
int bool_result = !!(cond); \
if (bool_result && !var) { \
var = 1; \
tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, \
"!("#cond")", 1); \
} \
PREDICT_UNLIKELY(bool_result); } ))
bool_result; } ))
#else
#define IF_BUG_ONCE__(cond,var) \
static int var = 0; \
if (PREDICT_UNLIKELY(cond) ? \
if ((cond) ? \
(var ? 1 : \
(var=1, \
tor_bug_occurred_(SHORT_FILE__, __LINE__, __func__, \
......@@ -148,7 +180,7 @@
*/
#define IF_BUG_ONCE(cond) \
IF_BUG_ONCE__((cond), \
IF_BUG_ONCE__(ASSERT_PREDICT_UNLIKELY_(cond), \
IF_BUG_ONCE_VARNAME__(__LINE__))
/** Define this if you want Tor to crash when any problem comes up,
......@@ -170,4 +202,3 @@ void tor_set_failed_assertion_callback(void (*fn)(void));
#endif
#endif
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment