[sanitizer] Intercept __xpg_strerror_r.

llvm-svn: 195839

compiler-rt/lib/msan/lit_tests/strerror_r-non-gnu.c

@@ -0,0 +1,18 @@
+// RUN: %clang_msan -std=c99 -O0 -g %s -o %t && %t
+
+// strerror_r under a weird set of circumstances can be redirected to
+// __xpg_strerror_r. Test that MSan handles this correctly.
+
+#define _POSIX_C_SOURCE 200112
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+
+int main() {
+  char buf[1000];
+  int res = strerror_r(EINVAL, buf, sizeof(buf));
+  assert(!res);
+  volatile int z = strlen(buf);
+  return 0;
+}

compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc

@@ -1848,6 +1848,21 @@ INTERCEPTOR(char *, strerror_r, int errnum, char *buf, SIZE_T buflen) {
 #define INIT_STRERROR_R
 #endif
 
+#if SANITIZER_INTERCEPT_XPG_STRERROR_R
+INTERCEPTOR(int, __xpg_strerror_r, int errnum, char *buf, SIZE_T buflen) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, __xpg_strerror_r, errnum, buf, buflen);
+  int res = REAL(__xpg_strerror_r)(errnum, buf, buflen);
+  // This version always returns a null-terminated string.
+  if (buf && buflen)
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, buf, REAL(strlen)(buf) + 1);
+  return res;
+}
+#define INIT_XPG_STRERROR_R COMMON_INTERCEPT_FUNCTION(__xpg_strerror_r);
+#else
+#define INIT_XPG_STRERROR_R
+#endif
+
 #if SANITIZER_INTERCEPT_SCANDIR
 typedef int (*scandir_filter_f)(const struct __sanitizer_dirent *);
 typedef int (*scandir_compar_f)(const struct __sanitizer_dirent **,
@@ -2895,6 +2910,7 @@ INTERCEPTOR(SSIZE_T, getdelim, char **lineptr, SIZE_T *n, int delim,
   INIT_SCHED_GETAFFINITY;                  \
   INIT_STRERROR;                           \
   INIT_STRERROR_R;                         \
+  INIT_XPG_STRERROR_R;                     \
   INIT_SCANDIR;                            \
   INIT_SCANDIR64;                          \
   INIT_GETGROUPS;                          \

compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h

@@ -120,6 +120,7 @@
 # define SANITIZER_INTERCEPT_SCHED_GETAFFINITY SI_LINUX_NOT_ANDROID
 # define SANITIZER_INTERCEPT_STRERROR SI_NOT_WINDOWS
 # define SANITIZER_INTERCEPT_STRERROR_R SI_NOT_WINDOWS
+# define SANITIZER_INTERCEPT_XPG_STRERROR_R SI_LINUX_NOT_ANDROID
 # define SANITIZER_INTERCEPT_SCANDIR SI_LINUX_NOT_ANDROID
 # define SANITIZER_INTERCEPT_SCANDIR64 SI_LINUX_NOT_ANDROID
 # define SANITIZER_INTERCEPT_GETGROUPS SI_NOT_WINDOWS

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

@@ -361,6 +361,7 @@ void StatOutput(u64 *stat) {
   name[StatInt_sched_getaffinity]        = "  sched_getaffinity               ";
   name[StatInt_strerror]                 = "  strerror                        ";
   name[StatInt_strerror_r]               = "  strerror_r                      ";
+  name[StatInt___xpg_strerror_r]         = "  __xpg_strerror_r                ";
   name[StatInt_scandir]                  = "  scandir                         ";
   name[StatInt_scandir64]                = "  scandir64                       ";
   name[StatInt_getgroups]                = "  getgroups                       ";

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

@@ -356,6 +356,7 @@ enum StatType {
   StatInt_sched_getaffinity,
   StatInt_strerror,
   StatInt_strerror_r,
+  StatInt___xpg_strerror_r,
   StatInt_scandir,
   StatInt_scandir64,
   StatInt_getgroups,