src/common/util_bug.c

   1 /* Copyright (c) 2003, Roger Dingledine
   2  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   3  * Copyright (c) 2007-2017, The Tor Project, Inc. */
   4 /* See LICENSE for licensing information */
   5
   6 /**
   7  * \file util_bug.c
   8  **/
   9
  10 #include "orconfig.h"
  11 #include "util_bug.h"
  12 #include "torlog.h"
  13 #include "backtrace.h"
  14 #include "container.h"
  15
  16 #ifdef __COVERITY__
  17 int bug_macro_deadcode_dummy__ = 0;
  18 #endif
  19
  20 #ifdef TOR_UNIT_TESTS
  21 static void (*failed_assertion_cb)(void) = NULL;
  22 static int n_bugs_to_capture = 0;
  23 static smartlist_t *bug_messages = NULL;
  24 #define capturing_bugs() (bug_messages != NULL && n_bugs_to_capture)
  25 void
  26 tor_capture_bugs_(int n)
  27 {
  28   tor_end_capture_bugs_();
  29   bug_messages = smartlist_new();
  30   n_bugs_to_capture = n;
  31 }
  32 void
  33 tor_end_capture_bugs_(void)
  34 {
  35   n_bugs_to_capture = 0;
  36   if (!bug_messages)
  37     return;
  38   SMARTLIST_FOREACH(bug_messages, char *, cp, tor_free(cp));
  39   smartlist_free(bug_messages);
  40   bug_messages = NULL;
  41 }
  42 const smartlist_t *
  43 tor_get_captured_bug_log_(void)
  44 {
  45   return bug_messages;
  46 }
  47 static void
  48 add_captured_bug(const char *s)
  49 {
  50   --n_bugs_to_capture;
  51   smartlist_add_strdup(bug_messages, s);
  52 }
  53 /** Set a callback to be invoked when we get any tor_bug_occurred_
  54  * invocation. We use this in the unit tests so that a nonfatal
  55  * assertion failure can also count as a test failure.
  56  */
  57 void
  58 tor_set_failed_assertion_callback(void (*fn)(void))
  59 {
  60   failed_assertion_cb = fn;
  61 }
  62 #else /* !(defined(TOR_UNIT_TESTS)) */
  63 #define capturing_bugs() (0)
  64 #define add_captured_bug(s) do { } while (0)
  65 #endif /* defined(TOR_UNIT_TESTS) */
  66
  67 /** Helper for tor_assert: report the assertion failure. */
  68 void
  69 tor_assertion_failed_(const char *fname, unsigned int line,
  70                       const char *func, const char *expr)
  71 {
  72   char buf[256];
  73   log_err(LD_BUG, "%s:%u: %s: Assertion %s failed; aborting.",
  74           fname, line, func, expr);
  75   tor_snprintf(buf, sizeof(buf),
  76                "Assertion %s failed in %s at %s:%u",
  77                expr, func, fname, line);
  78   log_backtrace(LOG_ERR, LD_BUG, buf);
  79 }
  80
  81 /** Helper for tor_assert_nonfatal: report the assertion failure. */
  82 void
  83 tor_bug_occurred_(const char *fname, unsigned int line,
  84                   const char *func, const char *expr,
  85                   int once)
  86 {
  87   char buf[256];
  88   const char *once_str = once ?
  89     " (Future instances of this warning will be silenced.)": "";
  90   if (! expr) {
  91     if (capturing_bugs()) {
  92       add_captured_bug("This line should not have been reached.");
  93       return;
  94     }
  95     log_warn(LD_BUG, "%s:%u: %s: This line should not have been reached.%s",
  96              fname, line, func, once_str);
  97     tor_snprintf(buf, sizeof(buf),
  98                  "Line unexpectedly reached at %s at %s:%u",
  99                  func, fname, line);
 100   } else {
 101     if (capturing_bugs()) {
 102       add_captured_bug(expr);
 103       return;
 104     }
 105     log_warn(LD_BUG, "%s:%u: %s: Non-fatal assertion %s failed.%s",
 106              fname, line, func, expr, once_str);
 107     tor_snprintf(buf, sizeof(buf),
 108                  "Non-fatal assertion %s failed in %s at %s:%u",
 109                  expr, func, fname, line);
 110   }
 111   log_backtrace(LOG_WARN, LD_BUG, buf);
 112
 113 #ifdef TOR_UNIT_TESTS
 114   if (failed_assertion_cb) {
 115     failed_assertion_cb();
 116   }
 117 #endif
 118 }
 119