[lldb] Use file to synchronize TestDeepBundle and TestBundleWithDotInFilename

[JDevlieghere]

Summary

Currently these two tests use an arbitrary wait of 5 seconds for the inferior to finish setting up. When the test machine is under heavy load this sometimes is insufficient leading to spurious test failures. This patch adds synchronization trough a token on the file system. In addition to making the test more reliable it also makes it much faster because we no longer have to wait the full 5 seconds if the setup was completed faster than that.

[teemperor]

This fills my heart with joy.

lldb/test/API/macosx/find-dsym/bundle-with-dot-in-filename/TestBundleWithDotInFilename.py

def tearDown(self):
 
         # Call super's tearDown().
         TestBase.tearDown(self)
 
     @skipIfRemote
     @skipUnlessDarwin
     # This test is explicitly a dSYM test, it doesn't need to run for any other config.
     @skipIf(debug_info=no_match(["dsym"]))
+    @skipIfReproducer # File synchronization is not supported during replay.
     def test_attach_and_check_dsyms(self):
         """Test attach to binary, see if the bundle dSYM is found"""
         exe = self.getBuildArtifact(exe_name)
         self.build()
         os.chdir(self.getBuildDir());
-        popen = self.spawnSubprocess(exe)
 
-        # Give the inferior time to start up, dlopen a bundle, remove the bundle it linked in
-        sleep(5)
+        # Use a file as a synchronization point between test and inferior.
+        pid_file_path = lldbutil.append_to_process_working_directory(self,
+            "token_pid_%d" % (int(os.getpid())))
+        self.addTearDownHook(
+            lambda: self.run_platform_command(
+                "rm %s" %
+                (pid_file_path)))
+
+        popen = self.spawnSubprocess(exe, [pid_file_path])
+
+        # Wait for the inferior to start up, dlopen a bundle, remove the bundle it linked in
+        pid = lldbutil.wait_for_file_on_target(self, pid_file_path)
 
         # Since the library that was dlopen()'ed is now removed, lldb will need to find the
         # binary & dSYM via target.exec-search-paths
         settings_str = "settings set target.exec-search-paths " + self.get_process_working_directory() + "/hide.app"
         self.runCmd(settings_str)
 
         self.runCmd("process attach -p " + str(popen.pid))
 
         target = self.dbg.GetSelectedTarget()
         self.assertTrue(target.IsValid(), 'Should have a valid Target after attaching to process')
 
         setup_complete = target.FindFirstGlobalVariable("setup_is_complete")
         self.assertEquals(setup_complete.GetValueAsUnsigned(), 1, 'Check that inferior process has completed setup')
 
         # Find the bundle module, see if we found the dSYM too (they're both in "hide.app")
         i = 0
         while i < target.GetNumModules():
             mod = target.GetModuleAtIndex(i)
             if mod.GetFileSpec().GetFilename() == 'com.apple.sbd':
                 dsym_name = mod.GetSymbolFileSpec().GetFilename()
                 self.assertTrue (dsym_name == 'com.apple.sbd', "Check that we found the dSYM for the bundle that was loaded")
             i=i+1
         os.chdir(self.getSourceDir());
-
-if __name__ == '__main__':
-    unittest.main()

lldb/test/API/macosx/find-dsym/bundle-with-dot-in-filename/main.c

 #include <dlfcn.h>
 #include <unistd.h>
 #include <stdlib.h>
+#include <stdio.h>
 
 int setup_is_complete = 0;
 
-int main()
+int main(int argc, const char** argv)
 {
 
     void *handle = dlopen ("com.apple.sbd.xpc/com.apple.sbd", RTLD_NOW);
     if (handle)
     {
         if (dlsym(handle, "foo"))
         {
             system ("/bin/rm -rf com.apple.sbd.xpc com.apple.sbd.xpc.dSYM");
+
+            FILE *fp = fopen (argv[1], "w");
+            fclose (fp);
             setup_is_complete = 1;
 
             // At this point we want lldb to attach to the process.  If lldb attaches
             // before we've removed the dlopen'ed bundle, lldb will find the bundle
             // at its actual filepath and not have to do any tricky work, invalidating
             // the test.
 
             for (int loop_limiter = 0; loop_limiter < 100; loop_limiter++)
                 sleep (1);
         }
     }
     return 0;
 }

lldb/test/API/macosx/find-dsym/deep-bundle/TestDeepBundle.py

def tearDown(self):
 
         # Call super's tearDown().
         TestBase.tearDown(self)
 
     @skipIfRemote
     @skipUnlessDarwin
     # This test is explicitly a dSYM test, it doesn't need to run for any other config.
     @skipIf(debug_info=no_match(["dsym"]))
+    @skipIfReproducer # File synchronization is not supported during replay.
     def test_attach_and_check_dsyms(self):
         """Test attach to binary, see if the framework dSYM is found"""
         exe = self.getBuildArtifact(exe_name)
         self.build()
-        popen = self.spawnSubprocess(exe, [self.getBuildDir()])
 
-        # Give the inferior time to start up, dlopen a bundle, remove the bundle it linked in
-        sleep(5)
+        # Use a file as a synchronization point between test and inferior.
+        pid_file_path = lldbutil.append_to_process_working_directory(self,
+            "token_pid_%d" % (int(os.getpid())))
+        self.addTearDownHook(
+            lambda: self.run_platform_command(
+                "rm %s" %
+                (pid_file_path)))
+
+        popen = self.spawnSubprocess(exe, [self.getBuildDir(),  pid_file_path])
+
+        # Wait for the inferior to start up, dlopen a bundle, remove the bundle it linked in
+        pid = lldbutil.wait_for_file_on_target(self, pid_file_path)
 
         # Since the library that was dlopen()'ed is now removed, lldb will need to find the
         # binary & dSYM via target.exec-search-paths
         settings_str = "settings set target.exec-search-paths " + self.get_process_working_directory() + "/hide.app"
         self.runCmd(settings_str)
         self.runCmd("process attach -p " + str(popen.pid))
 
         target = self.dbg.GetSelectedTarget()

lldb/test/API/macosx/find-dsym/deep-bundle/main.c

 #include <MyFramework/MyFramework.h>
 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
 
 int setup_is_complete = 0;
 
 int main(int argc, const char **argv)
 {
     char command[8192];
     sprintf (command,
              "/bin/rm -rf %s/MyFramework %s/MyFramework.framework %s/MyFramework.framework.dSYM",
              argv[1], argv[1], argv[1]);
     system (command);
 
+    FILE *fp = fopen (argv[2], "w");
+    fclose (fp);
     setup_is_complete = 1;
 
     // At this point we want lldb to attach to the process.  If lldb attaches
     // before we've removed the framework we're running against, it will be
     // easy for lldb to find the binary & dSYM without using target.exec-search-paths,
     // which is the point of this test.
 
     for (int loop_limiter = 0; loop_limiter < 100; loop_limiter++)
         sleep (1);
 
      return foo();
 }