[sanitizer] Intercept backtrace, backtrace_symbols.

llvm-svn: 191516

compiler-rt/lib/msan/lit_tests/backtrace.cc

@@ -0,0 +1,26 @@
+// RUN: %clangxx_msan -m64 -O0 %s -o %t && %t
+
+#include <assert.h>
+#include <execinfo.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+__attribute__((noinline))
+void f() {
+  void *buf[10];
+  int sz = backtrace(buf, sizeof(buf) / sizeof(*buf));
+  assert(sz > 0);
+  for (int i = 0; i < sz; ++i)
+    if (!buf[i])
+      exit(1);
+  char **s = backtrace_symbols(buf, sz);
+  assert(s > 0);
+  for (int i = 0; i < sz; ++i)
+    printf("%d\n", strlen(s[i]));
+}
+
+int main(void) {
+  f();
+  return 0;
+}

compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc

@@ -2114,6 +2114,36 @@ INTERCEPTOR(int, sigprocmask, int how, __sanitizer_sigset_t *set,
 #define INIT_SIGPROCMASK
 #endif
 
+#if SANITIZER_INTERCEPT_BACKTRACE
+INTERCEPTOR(int, backtrace, void **buffer, int size) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, backtrace, buffer, size);
+  int res = REAL(backtrace)(buffer, size);
+  if (res && buffer)
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, buffer, res * sizeof(*buffer));
+  return res;
+}
+
+INTERCEPTOR(char **, backtrace_symbols, void **buffer, int size) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, backtrace_symbols, buffer, size);
+  if (buffer && size)
+    COMMON_INTERCEPTOR_READ_RANGE(ctx, buffer, size * sizeof(*buffer));
+  char ** res = REAL(backtrace_symbols)(buffer, size);
+  if (res && size) {
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, res, size * sizeof(*res));
+    for (int i = 0; i < size; ++i)
+      COMMON_INTERCEPTOR_WRITE_RANGE(ctx, res[i], REAL(strlen(res[i])) + 1);
+  }
+  return res;
+}
+#define INIT_BACKTRACE           \
+  INTERCEPT_FUNCTION(backtrace); \
+  INTERCEPT_FUNCTION(backtrace_symbols);
+#else
+#define INIT_BACKTRACE
+#endif
+
 #define SANITIZER_COMMON_INTERCEPTORS_INIT \
   INIT_STRCMP;                             \
   INIT_STRNCMP;                            \
@@ -2189,4 +2219,5 @@ INTERCEPTOR(int, sigprocmask, int how, __sanitizer_sigset_t *set,
   INIT_SIGTIMEDWAIT;                       \
   INIT_SIGSETOPS;                          \
   INIT_SIGPENDING;                         \
-  INIT_SIGPROCMASK;
+  INIT_SIGPROCMASK;                        \
+  INIT_BACKTRACE;

compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h

@@ -125,5 +125,6 @@
 # define SANITIZER_INTERCEPT_SIGSETOPS SI_NOT_WINDOWS
 # define SANITIZER_INTERCEPT_SIGPENDING SI_NOT_WINDOWS
 # define SANITIZER_INTERCEPT_SIGPROCMASK SI_NOT_WINDOWS
+# define SANITIZER_INTERCEPT_BACKTRACE SI_LINUX_NOT_ANDROID
 
 #endif  // #ifndef SANITIZER_PLATFORM_INTERCEPTORS_H

compiler-rt/lib/tsan/rtl/tsan_stat.cc

@@ -369,6 +369,8 @@ void StatOutput(u64 *stat) {
   name[StatInt_sigfillset]               = "  sigfillset                      ";
   name[StatInt_sigpending]               = "  sigpending                      ";
   name[StatInt_sigprocmask]              = "  sigprocmask                     ";
+  name[StatInt_backtrace]                = "  backtrace                       ";
+  name[StatInt_backtrace_symbols]        = "  backtrace_symbols               ";
 
   name[StatAnnotation]                   = "Dynamic annotations               ";
   name[StatAnnotateHappensBefore]        = "  HappensBefore                   ";

compiler-rt/lib/tsan/rtl/tsan_stat.h

@@ -364,6 +364,8 @@ enum StatType {
   StatInt_sigfillset,
   StatInt_sigpending,
   StatInt_sigprocmask,
+  StatInt_backtrace,
+  StatInt_backtrace_symbols,
 
   // Dynamic annotations.
   StatAnnotation,