1 files changed, 653 insertions, 0 deletions
diff --git a/contrib/llvm/tools/lldb/source/Plugins/Process/Darwin/DarwinProcessLauncher.cpp b/contrib/llvm/tools/lldb/source/Plugins/Process/Darwin/DarwinProcessLauncher.cpp
new file mode 100644
index 0000000..63b1ae6
--- /dev/null
+++ b/contrib/llvm/tools/lldb/source/Plugins/Process/Darwin/DarwinProcessLauncher.cpp
@@ -0,0 +1,653 @@
+//===-- DarwinProcessLauncher.cpp -------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+//
+//  DarwinProcessLauncher.cpp
+//  lldb
+//
+//  Created by Todd Fiala on 8/30/16.
+//
+//
+
+#include "DarwinProcessLauncher.h"
+
+// C includes
+#include <spawn.h>
+#include <sys/ptrace.h>
+#include <sys/stat.h>
+#include <sys/sysctl.h>
+
+#ifndef _POSIX_SPAWN_DISABLE_ASLR
+#define _POSIX_SPAWN_DISABLE_ASLR 0x0100
+#endif
+
+// LLDB includes
+#include "lldb/lldb-enumerations.h"
+
+#include "lldb/Core/Error.h"
+#include "lldb/Core/Log.h"
+#include "lldb/Core/StreamString.h"
+#include "lldb/Target/ProcessLaunchInfo.h"
+#include "lldb/Utility/PseudoTerminal.h"
+
+#include "CFBundle.h"
+#include "CFString.h"
+
+using namespace lldb;
+using namespace lldb_private;
+using namespace lldb_private::process_darwin;
+using namespace lldb_private::darwin_process_launcher;
+
+namespace {
+static LaunchFlavor g_launch_flavor = LaunchFlavor::Default;
+}
+
+namespace lldb_private {
+namespace darwin_process_launcher {
+
+static uint32_t GetCPUTypeForLocalProcess(::pid_t pid) {
+  int mib[CTL_MAXNAME] = {
+      0,
+  };
+  size_t len = CTL_MAXNAME;
+  if (::sysctlnametomib("sysctl.proc_cputype", mib, &len))
+    return 0;
+
+  mib[len] = pid;
+  len++;
+
+  cpu_type_t cpu;
+  size_t cpu_len = sizeof(cpu);
+  if (::sysctl(mib, static_cast<u_int>(len), &cpu, &cpu_len, 0, 0))
+    cpu = 0;
+  return cpu;
+}
+
+static bool ResolveExecutablePath(const char *path, char *resolved_path,
+                                  size_t resolved_path_size) {
+  if (path == NULL || path[0] == '\0')
+    return false;
+
+  char max_path[PATH_MAX];
+  std::string result;
+  CFString::GlobPath(path, result);
+
+  if (result.empty())
+    result = path;
+
+  struct stat path_stat;
+  if (::stat(path, &path_stat) == 0) {
+    if ((path_stat.st_mode & S_IFMT) == S_IFDIR) {
+      CFBundle bundle(path);
+      CFReleaser<CFURLRef> url(bundle.CopyExecutableURL());
+      if (url.get()) {
+        if (::CFURLGetFileSystemRepresentation(
+                url.get(), true, (UInt8 *)resolved_path, resolved_path_size))
+          return true;
+      }
+    }
+  }
+
+  if (realpath(path, max_path)) {
+    // Found the path relatively...
+    ::strncpy(resolved_path, max_path, resolved_path_size);
+    return strlen(resolved_path) + 1 < resolved_path_size;
+  } else {
+    // Not a relative path, check the PATH environment variable if the
+    const char *PATH = getenv("PATH");
+    if (PATH) {
+      const char *curr_path_start = PATH;
+      const char *curr_path_end;
+      while (curr_path_start && *curr_path_start) {
+        curr_path_end = strchr(curr_path_start, ':');
+        if (curr_path_end == NULL) {
+          result.assign(curr_path_start);
+          curr_path_start = NULL;
+        } else if (curr_path_end > curr_path_start) {
+          size_t len = curr_path_end - curr_path_start;
+          result.assign(curr_path_start, len);
+          curr_path_start += len + 1;
+        } else
+          break;
+
+        result += '/';
+        result += path;
+        struct stat s;
+        if (stat(result.c_str(), &s) == 0) {
+          ::strncpy(resolved_path, result.c_str(), resolved_path_size);
+          return result.size() + 1 < resolved_path_size;
+        }
+      }
+    }
+  }
+  return false;
+}
+
+// TODO check if we have a general purpose fork and exec.  We may be
+// able to get rid of this entirely.
+static Error ForkChildForPTraceDebugging(const char *path, char const *argv[],
+                                         char const *envp[], ::pid_t *pid,
+                                         int *pty_fd) {
+  Error error;
+  if (!path || !argv || !envp || !pid || !pty_fd) {
+    error.SetErrorString("invalid arguments");
+    return error;
+  }
+
+  // Use a fork that ties the child process's stdin/out/err to a pseudo
+  // terminal so we can read it in our MachProcess::STDIOThread
+  // as unbuffered io.
+  lldb_utility::PseudoTerminal pty;
+  char fork_error[256];
+  memset(fork_error, 0, sizeof(fork_error));
+  *pid = static_cast<::pid_t>(pty.Fork(fork_error, sizeof(fork_error)));
+  if (*pid < 0) {
+    //--------------------------------------------------------------
+    // Error during fork.
+    //--------------------------------------------------------------
+    *pid = static_cast<::pid_t>(LLDB_INVALID_PROCESS_ID);
+    error.SetErrorStringWithFormat("%s(): fork failed: %s", __FUNCTION__,
+                                   fork_error);
+    return error;
+  } else if (pid == 0) {
+    //--------------------------------------------------------------
+    // Child process
+    //--------------------------------------------------------------
+
+    // Debug this process.
+    ::ptrace(PT_TRACE_ME, 0, 0, 0);
+
+    // Get BSD signals as mach exceptions.
+    ::ptrace(PT_SIGEXC, 0, 0, 0);
+
+    // If our parent is setgid, lets make sure we don't inherit those
+    // extra powers due to nepotism.
+    if (::setgid(getgid()) == 0) {
+      // Let the child have its own process group. We need to execute
+      // this call in both the child and parent to avoid a race
+      // condition between the two processes.
+
+      // Set the child process group to match its pid.
+      ::setpgid(0, 0);
+
+      // Sleep a bit to before the exec call.
+      ::sleep(1);
+
+      // Turn this process into the given executable.
+      ::execv(path, (char *const *)argv);
+    }
+    // Exit with error code. Child process should have taken
+    // over in above exec call and if the exec fails it will
+    // exit the child process below.
+    ::exit(127);
+  } else {
+    //--------------------------------------------------------------
+    // Parent process
+    //--------------------------------------------------------------
+    // Let the child have its own process group. We need to execute
+    // this call in both the child and parent to avoid a race condition
+    // between the two processes.
+
+    // Set the child process group to match its pid
+    ::setpgid(*pid, *pid);
+    if (pty_fd) {
+      // Release our master pty file descriptor so the pty class doesn't
+      // close it and so we can continue to use it in our STDIO thread
+      *pty_fd = pty.ReleaseMasterFileDescriptor();
+    }
+  }
+  return error;
+}
+
+static Error
+CreatePosixSpawnFileAction(const FileAction &action,
+                           posix_spawn_file_actions_t *file_actions) {
+  Error error;
+
+  // Log it.
+  Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
+  if (log) {
+    StreamString stream;
+    stream.PutCString("converting file action for posix_spawn(): ");
+    action.Dump(stream);
+    stream.Flush();
+    log->PutCString(stream.GetString().c_str());
+  }
+
+  // Validate args.
+  if (!file_actions) {
+    error.SetErrorString("mandatory file_actions arg is null");
+    return error;
+  }
+
+  // Build the posix file action.
+  switch (action.GetAction()) {
+  case FileAction::eFileActionOpen: {
+    const int error_code = ::posix_spawn_file_actions_addopen(
+        file_actions, action.GetFD(), action.GetPath(),
+        action.GetActionArgument(), 0);
+    if (error_code != 0) {
+      error.SetError(error_code, eErrorTypePOSIX);
+      return error;
+    }
+    break;
+  }
+
+  case FileAction::eFileActionClose: {
+    const int error_code =
+        ::posix_spawn_file_actions_addclose(file_actions, action.GetFD());
+    if (error_code != 0) {
+      error.SetError(error_code, eErrorTypePOSIX);
+      return error;
+    }
+    break;
+  }
+
+  case FileAction::eFileActionDuplicate: {
+    const int error_code = ::posix_spawn_file_actions_adddup2(
+        file_actions, action.GetFD(), action.GetActionArgument());
+    if (error_code != 0) {
+      error.SetError(error_code, eErrorTypePOSIX);
+      return error;
+    }
+    break;
+  }
+
+  case FileAction::eFileActionNone:
+  default:
+    if (log)
+      log->Printf("%s(): unsupported file action %u", __FUNCTION__,
+                  action.GetAction());
+    break;
+  }
+
+  return error;
+}
+
+static Error PosixSpawnChildForPTraceDebugging(const char *path,
+                                               ProcessLaunchInfo &launch_info,
+                                               ::pid_t *pid,
+                                               cpu_type_t *actual_cpu_type) {
+  Error error;
+  Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
+
+  if (!pid) {
+    error.SetErrorStringWithFormat("%s(): pid arg cannot be null",
+                                   __FUNCTION__);
+    return error;
+  }
+
+  posix_spawnattr_t attr;
+  short flags;
+  if (log) {
+    StreamString stream;
+    stream.Printf("%s(path='%s',...)\n", __FUNCTION__, path);
+    launch_info.Dump(stream, nullptr);
+    stream.Flush();
+    log->PutCString(stream.GetString().c_str());
+  }
+
+  int error_code;
+  if ((error_code = ::posix_spawnattr_init(&attr)) != 0) {
+    if (log)
+      log->Printf("::posix_spawnattr_init(&attr) failed");
+    error.SetError(error_code, eErrorTypePOSIX);
+    return error;
+  }
+
+  // Ensure we clean up the spawnattr structure however we exit this
+  // function.
+  std::unique_ptr<posix_spawnattr_t, int (*)(posix_spawnattr_t *)> spawnattr_up(
+      &attr, ::posix_spawnattr_destroy);
+
+  flags = POSIX_SPAWN_START_SUSPENDED | POSIX_SPAWN_SETSIGDEF |
+          POSIX_SPAWN_SETSIGMASK;
+  if (launch_info.GetFlags().Test(eLaunchFlagDisableASLR))
+    flags |= _POSIX_SPAWN_DISABLE_ASLR;
+
+  sigset_t no_signals;
+  sigset_t all_signals;
+  sigemptyset(&no_signals);
+  sigfillset(&all_signals);
+  ::posix_spawnattr_setsigmask(&attr, &no_signals);
+  ::posix_spawnattr_setsigdefault(&attr, &all_signals);
+
+  if ((error_code = ::posix_spawnattr_setflags(&attr, flags)) != 0) {
+    if (log)
+      log->Printf("::posix_spawnattr_setflags(&attr, "
+                  "POSIX_SPAWN_START_SUSPENDED%s) failed: %s",
+                  flags & _POSIX_SPAWN_DISABLE_ASLR
+                      ? " | _POSIX_SPAWN_DISABLE_ASLR"
+                      : "",
+                  strerror(error_code));
+    error.SetError(error_code, eErrorTypePOSIX);
+    return error;
+  }
+
+#if !defined(__arm__)
+
+  // We don't need to do this for ARM, and we really shouldn't now that we
+  // have multiple CPU subtypes and no posix_spawnattr call that allows us
+  // to set which CPU subtype to launch...
+  cpu_type_t desired_cpu_type = launch_info.GetArchitecture().GetMachOCPUType();
+  if (desired_cpu_type != LLDB_INVALID_CPUTYPE) {
+    size_t ocount = 0;
+    error_code =
+        ::posix_spawnattr_setbinpref_np(&attr, 1, &desired_cpu_type, &ocount);
+    if (error_code != 0) {
+      if (log)
+        log->Printf("::posix_spawnattr_setbinpref_np(&attr, 1, "
+                    "cpu_type = 0x%8.8x, count => %llu): %s",
+                    desired_cpu_type, (uint64_t)ocount, strerror(error_code));
+      error.SetError(error_code, eErrorTypePOSIX);
+      return error;
+    }
+    if (ocount != 1) {
+      error.SetErrorStringWithFormat("posix_spawnattr_setbinpref_np "
+                                     "did not set the expected number "
+                                     "of cpu_type entries: expected 1 "
+                                     "but was %zu",
+                                     ocount);
+      return error;
+    }
+  }
+#endif
+
+  posix_spawn_file_actions_t file_actions;
+  if ((error_code = ::posix_spawn_file_actions_init(&file_actions)) != 0) {
+    if (log)
+      log->Printf("::posix_spawn_file_actions_init(&file_actions) "
+                  "failed: %s",
+                  strerror(error_code));
+    error.SetError(error_code, eErrorTypePOSIX);
+    return error;
+  }
+
+  // Ensure we clean up file actions however we exit this.  When the
+  // file_actions_up below goes out of scope, we'll get our file action
+  // cleanup.
+  std::unique_ptr<posix_spawn_file_actions_t,
+                  int (*)(posix_spawn_file_actions_t *)>
+      file_actions_up(&file_actions, ::posix_spawn_file_actions_destroy);
+
+  // We assume the caller has setup the file actions appropriately.  We
+  // are not in the business of figuring out what we really need here.
+  // lldb-server will have already called FinalizeFileActions() as well
+  // to button these up properly.
+  const size_t num_actions = launch_info.GetNumFileActions();
+  for (size_t action_index = 0; action_index < num_actions; ++action_index) {
+    const FileAction *const action =
+        launch_info.GetFileActionAtIndex(action_index);
+    if (!action)
+      continue;
+
+    error = CreatePosixSpawnFileAction(*action, &file_actions);
+    if (!error.Success()) {
+      if (log)
+        log->Printf("%s(): error converting FileAction to posix_spawn "
+                    "file action: %s",
+                    __FUNCTION__, error.AsCString());
+      return error;
+    }
+  }
+
+  // TODO: Verify if we can set the working directory back immediately
+  // after the posix_spawnp call without creating a race condition???
+  const char *const working_directory =
+      launch_info.GetWorkingDirectory().GetCString();
+  if (working_directory && working_directory[0])
+    ::chdir(working_directory);
+
+  auto argv = launch_info.GetArguments().GetArgumentVector();
+  auto envp = launch_info.GetEnvironmentEntries().GetArgumentVector();
+  error_code = ::posix_spawnp(pid, path, &file_actions, &attr,
+                              (char *const *)argv, (char *const *)envp);
+  if (error_code != 0) {
+    if (log)
+      log->Printf("::posix_spawnp(pid => %p, path = '%s', file_actions "
+                  "= %p, attr = %p, argv = %p, envp = %p) failed: %s",
+                  pid, path, &file_actions, &attr, argv, envp,
+                  strerror(error_code));
+    error.SetError(error_code, eErrorTypePOSIX);
+    return error;
+  }
+
+  // Validate we got a pid.
+  if (pid == LLDB_INVALID_PROCESS_ID) {
+    error.SetErrorString("posix_spawn() did not indicate a failure but it "
+                         "failed to return a pid, aborting.");
+    return error;
+  }
+
+  if (actual_cpu_type) {
+    *actual_cpu_type = GetCPUTypeForLocalProcess(*pid);
+    if (log)
+      log->Printf("%s(): cpu type for launched process pid=%i: "
+                  "cpu_type=0x%8.8x",
+                  __FUNCTION__, *pid, *actual_cpu_type);
+  }
+
+  return error;
+}
+
+Error LaunchInferior(ProcessLaunchInfo &launch_info, int *pty_master_fd,
+                     LaunchFlavor *launch_flavor) {
+  Error error;
+  Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
+
+  if (!launch_flavor) {
+    error.SetErrorString("mandatory launch_flavor field was null");
+    return error;
+  }
+
+  if (log) {
+    StreamString stream;
+    stream.Printf("NativeProcessDarwin::%s(): launching with the "
+                  "following launch info:",
+                  __FUNCTION__);
+    launch_info.Dump(stream, nullptr);
+    stream.Flush();
+    log->PutCString(stream.GetString().c_str());
+  }
+
+  // Retrieve the binary name given to us.
+  char given_path[PATH_MAX];
+  given_path[0] = '\0';
+  launch_info.GetExecutableFile().GetPath(given_path, sizeof(given_path));
+
+  // Determine the manner in which we'll launch.
+  *launch_flavor = g_launch_flavor;
+  if (*launch_flavor == LaunchFlavor::Default) {
+    // Our default launch method is posix spawn
+    *launch_flavor = LaunchFlavor::PosixSpawn;
+#if defined WITH_FBS
+    // Check if we have an app bundle, if so launch using BackBoard Services.
+    if (strstr(given_path, ".app")) {
+      *launch_flavor = eLaunchFlavorFBS;
+    }
+#elif defined WITH_BKS
+    // Check if we have an app bundle, if so launch using BackBoard Services.
+    if (strstr(given_path, ".app")) {
+      *launch_flavor = eLaunchFlavorBKS;
+    }
+#elif defined WITH_SPRINGBOARD
+    // Check if we have an app bundle, if so launch using SpringBoard.
+    if (strstr(given_path, ".app")) {
+      *launch_flavor = eLaunchFlavorSpringBoard;
+    }
+#endif
+  }
+
+  // Attempt to resolve the binary name to an absolute path.
+  char resolved_path[PATH_MAX];
+  resolved_path[0] = '\0';
+
+  if (log)
+    log->Printf("%s(): attempting to resolve given binary path: \"%s\"",
+                __FUNCTION__, given_path);
+
+  // If we fail to resolve the path to our executable, then just use what we
+  // were given and hope for the best
+  if (!ResolveExecutablePath(given_path, resolved_path,
+                             sizeof(resolved_path))) {
+    if (log)
+      log->Printf("%s(): failed to resolve binary path, using "
+                  "what was given verbatim and hoping for the best",
+                  __FUNCTION__);
+    ::strncpy(resolved_path, given_path, sizeof(resolved_path));
+  } else {
+    if (log)
+      log->Printf("%s(): resolved given binary path to: \"%s\"", __FUNCTION__,
+                  resolved_path);
+  }
+
+  char launch_err_str[PATH_MAX];
+  launch_err_str[0] = '\0';
+
+  // TODO figure out how to handle QSetProcessEvent
+  // const char *process_event = ctx.GetProcessEvent();
+
+  // Ensure the binary is there.
+  struct stat path_stat;
+  if (::stat(resolved_path, &path_stat) == -1) {
+    error.SetErrorToErrno();
+    return error;
+  }
+
+  // Fork a child process for debugging
+  // state_callback(eStateLaunching);
+
+  const auto argv = launch_info.GetArguments().GetConstArgumentVector();
+  const auto envp =
+      launch_info.GetEnvironmentEntries().GetConstArgumentVector();
+
+  switch (*launch_flavor) {
+  case LaunchFlavor::ForkExec: {
+    ::pid_t pid = LLDB_INVALID_PROCESS_ID;
+    error = ForkChildForPTraceDebugging(resolved_path, argv, envp, &pid,
+                                        pty_master_fd);
+    if (error.Success()) {
+      launch_info.SetProcessID(static_cast<lldb::pid_t>(pid));
+    } else {
+      // Reset any variables that might have been set during a failed
+      // launch attempt.
+      if (pty_master_fd)
+        *pty_master_fd = -1;
+
+      // We're done.
+      return error;
+    }
+  } break;
+
+#ifdef WITH_FBS
+  case LaunchFlavor::FBS: {
+    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"));
+      m_flags |= eMachProcessFlagsUsingFBS;
+      if (BoardServiceLaunchForDebug(app_bundle_path.c_str(), argv, envp,
+                                     no_stdio, disable_aslr, event_data,
+                                     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
+    }
+  } break;
+#endif
+
+#ifdef WITH_BKS
+  case LaunchFlavor::BKS: {
+    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"));
+      m_flags |= eMachProcessFlagsUsingBKS;
+      if (BoardServiceLaunchForDebug(app_bundle_path.c_str(), argv, envp,
+                                     no_stdio, disable_aslr, event_data,
+                                     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
+    }
+  } break;
+#endif
+
+#ifdef WITH_SPRINGBOARD
+  case LaunchFlavor::SpringBoard: {
+    //  .../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"));
+      if (SBLaunchForDebug(app_bundle_path.c_str(), argv, envp, no_stdio,
+                           disable_aslr, 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
+    }
+  } break;
+#endif
+
+  case LaunchFlavor::PosixSpawn: {
+    ::pid_t pid = LLDB_INVALID_PROCESS_ID;
+
+    // Retrieve paths for stdin/stdout/stderr.
+    cpu_type_t actual_cpu_type = 0;
+    error = PosixSpawnChildForPTraceDebugging(resolved_path, launch_info, &pid,
+                                              &actual_cpu_type);
+    if (error.Success()) {
+      launch_info.SetProcessID(static_cast<lldb::pid_t>(pid));
+      if (pty_master_fd)
+        *pty_master_fd = launch_info.GetPTY().ReleaseMasterFileDescriptor();
+    } else {
+      // Reset any variables that might have been set during a failed
+      // launch attempt.
+      if (pty_master_fd)
+        *pty_master_fd = -1;
+
+      // We're done.
+      return error;
+    }
+    break;
+  }
+
+  default:
+    // Invalid launch flavor.
+    error.SetErrorStringWithFormat("NativeProcessDarwin::%s(): unknown "
+                                   "launch flavor %d",
+                                   __FUNCTION__, (int)*launch_flavor);
+    return error;
+  }
+
+  if (launch_info.GetProcessID() == LLDB_INVALID_PROCESS_ID) {
+    // If we don't have a valid process ID and no one has set the error,
+    // then return a generic error.
+    if (error.Success())
+      error.SetErrorStringWithFormat("%s(): failed to launch, no reason "
+                                     "specified",
+                                     __FUNCTION__);
+  }
+
+  // We're done with the launch side of the operation.
+  return error;
+}
+}
+} // namespaces