1 files changed, 118 insertions, 0 deletions
diff --git a/libsanitizer/asan/asan_posix.cc b/libsanitizer/asan/asan_posix.cc
new file mode 100644
index 00000000000..177b84ae67f
--- /dev/null
+++ b/libsanitizer/asan/asan_posix.cc
@@ -0,0 +1,118 @@
+//===-- asan_linux.cc -----------------------------------------------------===//
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of AddressSanitizer, an address sanity checker.
+//
+// Posix-specific details.
+//===----------------------------------------------------------------------===//
+#if defined(__linux__) || defined(__APPLE__)
+
+#include "asan_internal.h"
+#include "asan_interceptors.h"
+#include "asan_mapping.h"
+#include "asan_report.h"
+#include "asan_stack.h"
+#include "asan_thread_registry.h"
+#include "sanitizer_common/sanitizer_libc.h"
+#include "sanitizer_common/sanitizer_procmaps.h"
+
+#include <pthread.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <unistd.h>
+
+static const uptr kAltStackSize = SIGSTKSZ * 4;  // SIGSTKSZ is not enough.
+
+namespace __asan {
+
+static void MaybeInstallSigaction(int signum,
+                                  void (*handler)(int, siginfo_t *, void *)) {
+  if (!AsanInterceptsSignal(signum))
+    return;
+  struct sigaction sigact;
+  REAL(memset)(&sigact, 0, sizeof(sigact));
+  sigact.sa_sigaction = handler;
+  sigact.sa_flags = SA_SIGINFO;
+  if (flags()->use_sigaltstack) sigact.sa_flags |= SA_ONSTACK;
+  CHECK(0 == REAL(sigaction)(signum, &sigact, 0));
+  if (flags()->verbosity >= 1) {
+    Report("Installed the sigaction for signal %d\n", signum);
+  }
+}
+
+static void     ASAN_OnSIGSEGV(int, siginfo_t *siginfo, void *context) {
+  uptr addr = (uptr)siginfo->si_addr;
+  // Write the first message using the bullet-proof write.
+  if (13 != internal_write(2, "ASAN:SIGSEGV\n", 13)) Die();
+  uptr pc, sp, bp;
+  GetPcSpBp(context, &pc, &sp, &bp);
+  ReportSIGSEGV(pc, sp, bp, addr);
+}
+
+void SetAlternateSignalStack() {
+  stack_t altstack, oldstack;
+  CHECK(0 == sigaltstack(0, &oldstack));
+  // If the alternate stack is already in place, do nothing.
+  if ((oldstack.ss_flags & SS_DISABLE) == 0) return;
+  // TODO(glider): the mapped stack should have the MAP_STACK flag in the
+  // future. It is not required by man 2 sigaltstack now (they're using
+  // malloc()).
+  void* base = MmapOrDie(kAltStackSize, __FUNCTION__);
+  altstack.ss_sp = base;
+  altstack.ss_flags = 0;
+  altstack.ss_size = kAltStackSize;
+  CHECK(0 == sigaltstack(&altstack, 0));
+  if (flags()->verbosity > 0) {
+    Report("Alternative stack for T%d set: [%p,%p)\n",
+           asanThreadRegistry().GetCurrentTidOrInvalid(),
+           altstack.ss_sp, (char*)altstack.ss_sp + altstack.ss_size);
+  }
+}
+
+void UnsetAlternateSignalStack() {
+  stack_t altstack, oldstack;
+  altstack.ss_sp = 0;
+  altstack.ss_flags = SS_DISABLE;
+  altstack.ss_size = 0;
+  CHECK(0 == sigaltstack(&altstack, &oldstack));
+  UnmapOrDie(oldstack.ss_sp, oldstack.ss_size);
+}
+
+void InstallSignalHandlers() {
+  // Set the alternate signal stack for the main thread.
+  // This will cause SetAlternateSignalStack to be called twice, but the stack
+  // will be actually set only once.
+  if (flags()->use_sigaltstack) SetAlternateSignalStack();
+  MaybeInstallSigaction(SIGSEGV, ASAN_OnSIGSEGV);
+  MaybeInstallSigaction(SIGBUS, ASAN_OnSIGSEGV);
+}
+
+// ---------------------- TSD ---------------- {{{1
+
+static pthread_key_t tsd_key;
+static bool tsd_key_inited = false;
+void AsanTSDInit(void (*destructor)(void *tsd)) {
+  CHECK(!tsd_key_inited);
+  tsd_key_inited = true;
+  CHECK(0 == pthread_key_create(&tsd_key, destructor));
+}
+
+void *AsanTSDGet() {
+  CHECK(tsd_key_inited);
+  return pthread_getspecific(tsd_key);
+}
+
+void AsanTSDSet(void *tsd) {
+  CHECK(tsd_key_inited);
+  pthread_setspecific(tsd_key, tsd);
+}
+
+}  // namespace __asan
+
+#endif  // __linux__ || __APPLE_