[Sanitizer] Add the way to find binary in PATH

llvm-svn: 189799

compiler-rt/lib/sanitizer_common/sanitizer_common.h

@@ -134,6 +134,7 @@ bool FileExists(const char *filename);
 const char *GetEnv(const char *name);
 bool SetEnv(const char *name, const char *value);
 const char *GetPwd();
+char *FindPathToBinary(const char *name);
 u32 GetUid();
 void ReExec();
 bool StackSizeIsUnlimited();

compiler-rt/lib/sanitizer_common/sanitizer_posix.cc

@@ -173,6 +173,30 @@ const char *GetPwd() {
   return GetEnv("PWD");
 }
 
+char *FindPathToBinary(const char *name) {
+  const char *path = GetEnv("PATH");
+  if (!path)
+    return 0;
+  uptr name_len = internal_strlen(name);
+  InternalScopedBuffer<char> buffer(kMaxPathLength);
+  const char *beg = path;
+  while (true) {
+    const char *end = internal_strchrnul(beg, ':');
+    uptr prefix_len = end - beg;
+    if (prefix_len + name_len + 2 <= kMaxPathLength) {
+      internal_memcpy(buffer.data(), beg, prefix_len);
+      buffer[prefix_len] = '/';
+      internal_memcpy(&buffer[prefix_len + 1], name, name_len);
+      buffer[prefix_len + 1 + name_len] = '\0';
+      if (FileExists(buffer.data()))
+        return internal_strdup(buffer.data());
+    }
+    if (*end == '\0') break;
+    beg = end + 1;
+  }
+  return 0;
+}
+
 }  // namespace __sanitizer
 
 #endif  // SANITIZER_LINUX || SANITIZER_MAC

compiler-rt/lib/sanitizer_common/sanitizer_win.cc

@@ -196,6 +196,10 @@ void SetStackSizeLimitInBytes(uptr limit) {
   UNIMPLEMENTED();
 }
 
+char *FindPathToBinary(const char *name) {
+  UNIMPLEMENTED();
+}
+
 void SleepForSeconds(int seconds) {
   Sleep(seconds * 1000);
 }

compiler-rt/lib/sanitizer_common/tests/sanitizer_common_test.cc

@@ -10,6 +10,7 @@
 // This file is a part of ThreadSanitizer/AddressSanitizer runtime.
 //
 //===----------------------------------------------------------------------===//
+#include "sanitizer_common/sanitizer_allocator_internal.h"
 #include "sanitizer_common/sanitizer_common.h"
 #include "sanitizer_common/sanitizer_libc.h"
 #include "sanitizer_common/sanitizer_platform.h"
@@ -173,4 +174,13 @@ TEST(SanitizerCommon, InternalBinarySearch) {
   ASSERT_EQ(InternalBinarySearch(arr, 0, kSize, 7, UptrLess), kSize + 1);
 }
 
+#if SANITIZER_LINUX
+TEST(SanitizerCommon, FindPathToBinary) {
+  char *true_path = FindPathToBinary("true");
+  EXPECT_NE((char*)0, internal_strstr(true_path, "/bin/true"));
+  InternalFree(true_path);
+  EXPECT_EQ(0, FindPathToBinary("unexisting_binary.ergjeorj"));
+}
+#endif
+
 }  // namespace __sanitizer