release/src/router/dnscrypt/src/proxy/stack_trace.c

   1
   2 #include <config.h>
   3 #ifdef HAVE_SYS_CDEFS_H
   4 # include <sys/cdefs.h>
   5 #elif defined(HAVE_SYS_FEATURE_TESTS_H)
   6 # include <sys/feature_tests.h>
   7 #else
   8 # include <sys/types.h>
   9 #endif
  10 #if !defined(_XOPEN_SOURCE) || _XOPEN_SOURCE < 500
  11 # undef _XOPEN_SOURCE
  12 # define _XOPEN_SOURCE 500
  13 #endif
  14 #ifndef _GNU_SOURCE
  15 # define _GNU_SOURCE   1
  16 #endif
  17 #if !defined(HAVE_SYS_CDEFS_H) && !defined(HAVE_SYS_FEATURE_TESTS_H)
  18 # include <sys/types.h>
  19 #endif
  20
  21 #ifndef _WIN32
  22 # include <dlfcn.h>
  23 #endif
  24 #ifdef HAVE_EXECINFO_H
  25 # include <execinfo.h>
  26 #endif
  27 #include <signal.h>
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <unistd.h>
  31
  32 #include "stack_trace.h"
  33
  34 #ifdef __OpenBSD__
  35 # undef HAVE_BACKTRACE
  36 #endif
  37
  38 void
  39 stack_trace(void)
  40 {
  41 #ifndef HAVE_BACKTRACE
  42     fputs("This platform doesn't support backtrace() yet.\n", stderr);
  43 #else
  44     void  *trace[100];
  45     char **messages = NULL;
  46     int    i;
  47     int    trace_size = 0;
  48
  49     trace_size = backtrace(trace, sizeof(trace) / sizeof(trace[0]));
  50     messages   = backtrace_symbols(trace, trace_size);
  51     fprintf(stderr, "======== Stack trace ========\n");
  52     for (i = 1; i < trace_size; ++i) {
  53         fprintf(stderr, "%s\n", messages[i]);
  54     }
  55 #endif
  56 }
  57
  58 #ifdef HAVE_BACKTRACE
  59 static void
  60 stack_trace_signal_handler(int sig, siginfo_t *info, void *f) {
  61     (void) info;
  62     (void) f;
  63     stack_trace();
  64     kill(getpid(), sig);
  65     abort();
  66     /* NOTREACHED */
  67 }
  68 #endif
  69
  70 int
  71 stack_trace_on_crash(void)
  72 {
  73 #ifdef HAVE_BACKTRACE
  74     struct sigaction act;
  75
  76     sigemptyset(&act.sa_mask);
  77     act.sa_flags     = SA_NODEFER | SA_ONSTACK | SA_RESETHAND | SA_SIGINFO;
  78     act.sa_sigaction = stack_trace_signal_handler;
  79     sigaction(SIGABRT, &act, NULL);
  80     sigaction(SIGBUS,  &act, NULL);
  81     sigaction(SIGFPE,  &act, NULL);
  82 # ifdef SIGILL
  83     sigaction(SIGILL,  &act, NULL);
  84 # endif
  85     sigaction(SIGSEGV, &act, NULL);
  86 #endif
  87
  88     return 0;
  89 }
  90
  91 #ifdef GCC_TRACE
  92 # ifndef __APPLE__
  93 #  define profile_func_enter(A, B) __cyg_profile_func_enter(A, B)
  94 #  define profile_func_exit(A, B)  __cyg_profile_func_exit(A, B)
  95 # endif
  96
  97 static unsigned int call_level = 0U;
  98
  99 void
 100 profile_func_enter(void *this_fn, void *call_site)
 101 __attribute__((no_instrument_function));
 102
 103 void profile_func_enter(void *this_fn, void *call_site)
 104 {
 105     unsigned int level = 0U;
 106
 107     (void) call_site;
 108     ++call_level;
 109     Dl_info info;
 110     this_fn = __builtin_return_address(0);
 111     if (dladdr(this_fn, &info) == 0) {
 112         return;
 113     }
 114     if (info.dli_sname != NULL &&
 115         info.dli_sname[0] == '_' && info.dli_sname[1] == '_') {
 116         return;
 117     }
 118     while (level < call_level) {
 119         fputs("┃ ", stderr);
 120         level++;
 121     }
 122     fputs("┣━━┈", stderr);
 123     if (info.dli_sname != NULL && info.dli_sname[0] != 0) {
 124         fprintf(stderr, "%s()\n", info.dli_sname);
 125     } else {
 126         fprintf(stderr, "<%p>()\n", this_fn);
 127     }
 128 }
 129
 130 void
 131 profile_func_exit(void *this_fn, void *call_site)
 132 __attribute__((no_instrument_function));
 133
 134 void
 135 profile_func_exit(void *this_fn, void *call_site)
 136 {
 137     (void) this_fn;
 138     (void) call_site;
 139     if (call_level > 0U) {
 140         call_level--;
 141     }
 142 }
 143 #endif