[debugserver] Fix logic to extract app bundle from file path

[JDevlieghere]

Summary

Fix the logic to find the app bundle in a path by correctly accounting for paths containing multiple occurrences of .app. The new logic will correctly extract com.app.Foo.app from com.app.Foo.app/com.app.Foo.

rdar://74666208

[jasonmolenda]

Nice, LGTM.

lldb/tools/debugserver/source/MacOSX/MachProcess.mm

3174

I wouldn't conditionalize these messages on LOG_PROCESS, I would log unconditionally if the app launch failed (just DNBLog the errors, IMO)

lldb/tools/debugserver/source/MacOSX/MachProcess.mm

NSDictionary *version_info =
        @"/System/Library/CoreServices/SystemVersion.plist"];
     NSString *version_value = [version_info objectForKey: @"iOSSupportVersion"];
     if (const char *version_str = [version_value UTF8String])
       return version_str;
   }
   return {};
 }
 
+#if defined(WITH_SPRINGBOARD) || defined(WITH_BKS) || defined(WITH_FBS)
+/// Get the app bundle from the given path. Returns the empty string if the
+/// path doesn't appear to be an app bundle.
+static std::string GetAppBundle(std::string path) {
+  auto pos = path.rfind(".app");
+  // Path doesn't contain `.app`.
+  if (pos == std::string::npos)
+    return {};
+  // Path has `.app` extension.
+  if (pos == path.size() - 4)
+    return path.substr(0, pos + 4);
+
+  // Look for `.app` before a path separator.
+  do {
+    if (path[pos + 4] == '/')
+      return path.substr(0, pos + 4);
+    path = path.substr(0, pos);
+    pos = path.rfind(".app");
+  } while (pos != std::string::npos);
+
+  return {};
+}
+#endif
+
 // Do the process specific setup for attach.  If this returns NULL, then there's
 // no
 // platform specific stuff to be done to wait for the attach.  If you get
 // non-null,
 // pass that token to the CheckForProcess method, and then to
 // CleanupAfterAttach.
 
 //  Call PrepareForAttach before attaching to a process that has not yet
 //  launched
 // This returns a token that can be passed to CheckForProcess, and to
 // CleanupAfterAttach.
 // You should call CleanupAfterAttach to free the token, and do whatever other
 // cleanup seems good.
 
 const void *MachProcess::PrepareForAttach(const char *path,
                                           nub_launch_flavor_t launch_flavor,
                                           bool waitfor, DNBError &attach_err) {
 #if defined(WITH_SPRINGBOARD) || defined(WITH_BKS) || defined(WITH_FBS)
   // Tell SpringBoard to halt the next launch of this application on startup.
 
   if (!waitfor)
     return NULL;
 
-  const char *app_ext = strstr(path, ".app");
-  const bool is_app =
-      app_ext != NULL && (app_ext[4] == '\0' || app_ext[4] == '/');
-  if (!is_app) {
+  std::string app_bundle_path = GetAppBundle(path);
+  if (app_bundle_path.empty()) {
     DNBLogThreadedIf(
         LOG_PROCESS,
         "MachProcess::PrepareForAttach(): path '%s' doesn't contain .app, "
         "we can't tell springboard to wait for launch...",
         path);
     return NULL;
   }
 
if (launch_flavor != eLaunchFlavorBKS)
     return NULL;
 #elif defined(WITH_SPRINGBOARD)
   if (launch_flavor == eLaunchFlavorDefault)
     launch_flavor = eLaunchFlavorSpringBoard;
   if (launch_flavor != eLaunchFlavorSpringBoard)
     return NULL;
 #endif
 
-  std::string app_bundle_path(path, app_ext + strlen(".app"));
-
   CFStringRef bundleIDCFStr =
       CopyBundleIDForPath(app_bundle_path.c_str(), attach_err);
   std::string bundleIDStr;
   CFString::UTF8(bundleIDCFStr, bundleIDStr);
   DNBLogThreadedIf(LOG_PROCESS,
                    "CopyBundleIDForPath (%s, err_str) returned @\"%s\"",
                    app_bundle_path.c_str(), bundleIDStr.c_str());
 
pid_t MachProcess::LaunchForDebug(
 
   switch (launch_flavor) {
   case eLaunchFlavorForkExec:
     m_pid = MachProcess::ForkChildForPTraceDebugging(path, argv, envp, this,
                                                      launch_err);
     break;
 #ifdef WITH_FBS
   case eLaunchFlavorFBS: {
-    const char *app_ext = strstr(path, ".app");
-    if (app_ext && (app_ext[4] == '\0' || app_ext[4] == '/')) {
-      std::string app_bundle_path(path, app_ext + strlen(".app"));
+    std::string app_bundle_path = GetAppBundle(path);
+    if (!app_bundle_path.empty()) {
       m_flags |= (eMachProcessFlagsUsingFBS | eMachProcessFlagsBoardCalculated);
       if (BoardServiceLaunchForDebug(app_bundle_path.c_str(), argv, envp,
                                      no_stdio, disable_aslr, event_data,
                                      unmask_signals, launch_err) != 0)
         return m_pid; // A successful SBLaunchForDebug() returns and assigns a
                       // non-zero m_pid.
-      else
-        break; // We tried a FBS launch, but didn't succeed lets get out
     }
+    DNBLog("Failed to launch '%s' with FBS", app_bundle_path);
   } break;
 #endif
 #ifdef WITH_BKS
   case eLaunchFlavorBKS: {
-    const char *app_ext = strstr(path, ".app");
-    if (app_ext && (app_ext[4] == '\0' || app_ext[4] == '/')) {
-      std::string app_bundle_path(path, app_ext + strlen(".app"));
+    std::string app_bundle_path = GetAppBundle(path);
+    if (!app_bundle_path.empty()) {
       m_flags |= (eMachProcessFlagsUsingBKS | eMachProcessFlagsBoardCalculated);
       if (BoardServiceLaunchForDebug(app_bundle_path.c_str(), argv, envp,
                                      no_stdio, disable_aslr, event_data,
                                      unmask_signals, launch_err) != 0)
         return m_pid; // A successful SBLaunchForDebug() returns and assigns a
                       // non-zero m_pid.
-      else
-        break; // We tried a BKS launch, but didn't succeed lets get out
     }
+    DNBLog("Failed to launch '%s' with BKS", app_bundle_path);
   } break;
 #endif
 #ifdef WITH_SPRINGBOARD
-
   case eLaunchFlavorSpringBoard: {
-    //  .../whatever.app/whatever ?
-    //  Or .../com.apple.whatever.app/whatever -- be careful of ".app" in
-    //  "com.apple.whatever" here
-    const char *app_ext = strstr(path, ".app/");
-    if (app_ext == NULL) {
-      // .../whatever.app ?
-      int len = strlen(path);
-      if (len > 5) {
-        if (strcmp(path + len - 4, ".app") == 0) {
-          app_ext = path + len - 4;
-        }
-      }
-    }
-    if (app_ext) {
-      std::string app_bundle_path(path, app_ext + strlen(".app"));
+    std::string app_bundle_path = GetAppBundle(path);
+    if (!app_bundle_path.empty()) {
       if (SBLaunchForDebug(app_bundle_path.c_str(), argv, envp, no_stdio,
                            disable_aslr, unmask_signals, launch_err) != 0)
         return m_pid; // A successful SBLaunchForDebug() returns and assigns a
                       // non-zero m_pid.
-      else
-        break; // We tried a springboard launch, but didn't succeed lets get out
     }
+    DNBLog("Failed to launch '%s' with SpringBoard", app_bundle_path);
   } break;
 
 #endif
 
   case eLaunchFlavorPosixSpawn:
     m_pid = MachProcess::PosixSpawnChildForPTraceDebugging(
         path, DNBArchProtocol::GetCPUType(), DNBArchProtocol::GetCPUSubType(),
         argv, envp, working_directory, stdin_path, stdout_path, stderr_path,
         no_stdio, this, disable_aslr, launch_err);
     break;
 
   default:
-    // Invalid  launch
+    DNBLog("Failed to launch: invalid launch flavor: %d", launch_flavor);
     launch_err.SetError(NUB_GENERIC_ERROR, DNBError::Generic);
     return INVALID_NUB_PROCESS;
   }
 
   if (m_pid == INVALID_NUB_PROCESS) {
     // If we don't have a valid process ID and no one has set the error,
     // then return a generic error
     if (launch_err.Success())