Fix DynamicLibraryTest.cpp on FreeBSD and NetBSD

Summary:

After rL301562, on FreeBSD the DynamicLibrary unittests fail, because
the test uses getMainExecutable("DynamicLibraryTests", Ptr), and since
the path does not contain any slashes, retrieving the main executable
will not work.

Reimplement getMainExecutable() for FreeBSD and NetBSD using sysctl(3),
which is more reliable than fiddling with relative or absolute paths.

Also add retrieval of the original argv[] from the GoogleTest framework,
to use as a fallback for other OSes.

Reviewers: emaste, marsupial, hans, krytarowski

Reviewed By: krytarowski

Subscribers: krytarowski, llvm-commits

Differential Revision: https://reviews.llvm.org/D33171

llvm-svn: 303015

llvm/lib/Support/Unix/Path.inc

@@ -103,13 +103,16 @@
 #define STATVFS_F_FLAG(vfs) (vfs).f_flags
 #endif
 
+#if defined(__FreeBSD__) || defined(__NetBSD__)
+#include <sys/sysctl.h>
+#endif
+
 using namespace llvm;
 
 namespace llvm {
 namespace sys  {
 namespace fs {
-#if defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \
-    defined(__OpenBSD__) || defined(__minix) || defined(__FreeBSD_kernel__) || \
+#if defined(__Bitrig__) || defined(__OpenBSD__) || defined(__minix) || \
     defined(__linux__) || defined(__CYGWIN__) || defined(__DragonFly__) || \
     defined(_AIX)
 static int
@@ -164,7 +167,7 @@ getprogpath(char ret[PATH_MAX], const char *bin)
   free(pv);
   return nullptr;
 }
-#endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__
+#endif // Bitrig || OpenBSD || minix || linux || CYGWIN || DragonFly || AIX
 
 /// GetMainExecutable - Return the path to the main executable, given the
 /// value of argv[0] from program startup.
@@ -180,9 +183,24 @@ std::string getMainExecutable(const char *argv0, void *MainAddr) {
     if (realpath(exe_path, link_path))
       return link_path;
   }
-#elif defined(__FreeBSD__) || defined (__NetBSD__) || defined(__Bitrig__) || \
-      defined(__OpenBSD__) || defined(__minix) || defined(__DragonFly__) || \
-      defined(__FreeBSD_kernel__) || defined(_AIX)
+#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__NetBSD__)
+  int mib[4];
+  mib[0] = CTL_KERN;
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+  mib[1] = KERN_PROC;
+  mib[2] = KERN_PROC_PATHNAME;
+  mib[3] = -1;
+#else
+  mib[1] = KERN_PROC_ARGS;
+  mib[2] = -1;
+  mib[3] = KERN_PROC_PATHNAME;
+#endif
+  char exe_path[PATH_MAX];
+  size_t cb = sizeof(exe_path);
+  if (sysctl(mib, 4, exe_path, &cb, NULL, 0) == 0)
+    return exe_path;
+#elif defined(__Bitrig__) || defined(__OpenBSD__) || defined(__minix) || \
+      defined(__DragonFly__) || defined(_AIX)
   char exe_path[PATH_MAX];
 
   if (getprogpath(exe_path, argv0) != NULL)

llvm/unittests/Support/DynamicLibrary/DynamicLibraryTest.cpp

@@ -23,8 +23,10 @@ using namespace llvm::sys;
 extern "C" PIPSQUEAK_EXPORT const char *TestA() { return "ProcessCall"; }
 
 std::string LibPath() {
+  const std::vector<testing::internal::string>& Argvs = testing::internal::GetArgvs();
+  const char *Argv0 = Argvs.size() > 0 ? Argvs[0].c_str() : "DynamicLibraryTests";
   void *Ptr = (void*)(intptr_t)TestA;
-  std::string Path = fs::getMainExecutable("DynamicLibraryTests", Ptr);
+  std::string Path = fs::getMainExecutable(Argv0, Ptr);
   llvm::SmallString<256> Buf(path::parent_path(Path));
   path::append(Buf, "PipSqueak.so");
   return Buf.str();