view release on metacpan or  search on metacpan

libuv/src/win/process.c  view on Meta::CPAN

 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include <assert.h>
#include <io.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <limits.h>
#include <wchar.h>
#include <malloc.h>    /* alloca */

#include "uv.h"
#include "internal.h"
#include "handle-inl.h"
#include "req-inl.h"


#define SIGKILL         9


typedef struct env_var {
  const WCHAR* const wide;
  const WCHAR* const wide_eq;
  const size_t len; /* including null or '=' */
} env_var_t;

#define E_V(str) { L##str, L##str L"=", sizeof(str) }

static const env_var_t required_vars[] = { /* keep me sorted */
  E_V("HOMEDRIVE"),
  E_V("HOMEPATH"),
  E_V("LOGONSERVER"),
  E_V("PATH"),
  E_V("SYSTEMDRIVE"),
  E_V("SYSTEMROOT"),
  E_V("TEMP"),
  E_V("USERDOMAIN"),
  E_V("USERNAME"),
  E_V("USERPROFILE"),
  E_V("WINDIR"),
};
static size_t n_required_vars = ARRAY_SIZE(required_vars);


static HANDLE uv_global_job_handle_;
static uv_once_t uv_global_job_handle_init_guard_ = UV_ONCE_INIT;


static void uv__init_global_job_handle(void) {
  /* Create a job object and set it up to kill all contained processes when
   * it's closed. Since this handle is made non-inheritable and we're not
   * giving it to anyone, we're the only process holding a reference to it.
   * That means that if this process exits it is closed and all the processes
   * it contains are killed. All processes created with uv_spawn that are not
   * spawned with the UV_PROCESS_DETACHED flag are assigned to this job.
   *
   * We're setting the JOB_OBJECT_LIMIT_SILENT_BREAKAWAY_OK flag so only the
   * processes that we explicitly add are affected, and *their* subprocesses
   * are not. This ensures that our child processes are not limited in their
   * ability to use job control on Windows versions that don't deal with
   * nested jobs (prior to Windows 8 / Server 2012). It also lets our child
   * processes created detached processes without explicitly breaking away
   * from job control (which uv_spawn doesn't, either).
   */
  SECURITY_ATTRIBUTES attr;
  JOBOBJECT_EXTENDED_LIMIT_INFORMATION info;

  memset(&attr, 0, sizeof attr);
  attr.bInheritHandle = FALSE;

  memset(&info, 0, sizeof info);
  info.BasicLimitInformation.LimitFlags =
      JOB_OBJECT_LIMIT_BREAKAWAY_OK |
      JOB_OBJECT_LIMIT_SILENT_BREAKAWAY_OK |
      JOB_OBJECT_LIMIT_DIE_ON_UNHANDLED_EXCEPTION |
      JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE;

  uv_global_job_handle_ = CreateJobObjectW(&attr, NULL);
  if (uv_global_job_handle_ == NULL)
    uv_fatal_error(GetLastError(), "CreateJobObjectW");

  if (!SetInformationJobObject(uv_global_job_handle_,
                               JobObjectExtendedLimitInformation,
                               &info,
                               sizeof info))
    uv_fatal_error(GetLastError(), "SetInformationJobObject");
}


static int uv_utf8_to_utf16_alloc(const char* s, WCHAR** ws_ptr) {
  int ws_len, r;
  WCHAR* ws;

  ws_len = MultiByteToWideChar(CP_UTF8,
                               0,
                               s,
                               -1,
                               NULL,
                               0);
  if (ws_len <= 0) {
    return GetLastError();
  }

  ws = (WCHAR*) uv__malloc(ws_len * sizeof(WCHAR));
  if (ws == NULL) {
    return ERROR_OUTOFMEMORY;
  }

  r = MultiByteToWideChar(CP_UTF8,
                          0,
                          s,
                          -1,
                          ws,
                          ws_len);
  assert(r == ws_len);

  *ws_ptr = ws;
  return 0;
}


static void uv_process_init(uv_loop_t* loop, uv_process_t* handle) {
  uv__handle_init(loop, (uv_handle_t*) handle, UV_PROCESS);
  handle->exit_cb = NULL;
  handle->pid = 0;
  handle->exit_signal = 0;
  handle->wait_handle = INVALID_HANDLE_VALUE;
  handle->process_handle = INVALID_HANDLE_VALUE;
  handle->child_stdio_buffer = NULL;
  handle->exit_cb_pending = 0;

  UV_REQ_INIT(&handle->exit_req, UV_PROCESS_EXIT);
  handle->exit_req.data = handle;
}


/*
 * Path search functions
 */

/*
 * Helper function for search_path

libuv/src/win/process.c  view on Meta::CPAN

  startup.lpReserved2 = (BYTE*) process->child_stdio_buffer;

  startup.hStdInput = uv__stdio_handle(process->child_stdio_buffer, 0);
  startup.hStdOutput = uv__stdio_handle(process->child_stdio_buffer, 1);
  startup.hStdError = uv__stdio_handle(process->child_stdio_buffer, 2);

  process_flags = CREATE_UNICODE_ENVIRONMENT;

  if ((options->flags & UV_PROCESS_WINDOWS_HIDE_CONSOLE) ||
      (options->flags & UV_PROCESS_WINDOWS_HIDE)) {
    /* Avoid creating console window if stdio is not inherited. */
    for (i = 0; i < options->stdio_count; i++) {
      if (options->stdio[i].flags & UV_INHERIT_FD)
        break;
      if (i == options->stdio_count - 1)
        process_flags |= CREATE_NO_WINDOW;
    }
  }
  if ((options->flags & UV_PROCESS_WINDOWS_HIDE_GUI) ||
      (options->flags & UV_PROCESS_WINDOWS_HIDE)) {
    /* Use SW_HIDE to avoid any potential process window. */
    startup.wShowWindow = SW_HIDE;
  } else {
    startup.wShowWindow = SW_SHOWDEFAULT;
  }

  if (options->flags & UV_PROCESS_DETACHED) {
    /* Note that we're not setting the CREATE_BREAKAWAY_FROM_JOB flag. That
     * means that libuv might not let you create a fully daemonized process
     * when run under job control. However the type of job control that libuv
     * itself creates doesn't trickle down to subprocesses so they can still
     * daemonize.
     *
     * A reason to not do this is that CREATE_BREAKAWAY_FROM_JOB makes the
     * CreateProcess call fail if we're under job control that doesn't allow
     * breakaway.
     */
    process_flags |= DETACHED_PROCESS | CREATE_NEW_PROCESS_GROUP;
  }

  if (!CreateProcessW(application_path,
                     arguments,
                     NULL,
                     NULL,
                     1,
                     process_flags,
                     env,
                     cwd,
                     &startup,
                     &info)) {
    /* CreateProcessW failed. */
    err = GetLastError();
    goto done;
  }

  /* Spawn succeeded. Beyond this point, failure is reported asynchronously. */

  process->process_handle = info.hProcess;
  process->pid = info.dwProcessId;

  /* If the process isn't spawned as detached, assign to the global job object
   * so windows will kill it when the parent process dies. */
  if (!(options->flags & UV_PROCESS_DETACHED)) {
    uv_once(&uv_global_job_handle_init_guard_, uv__init_global_job_handle);

    if (!AssignProcessToJobObject(uv_global_job_handle_, info.hProcess)) {
      /* AssignProcessToJobObject might fail if this process is under job
       * control and the job doesn't have the
       * JOB_OBJECT_LIMIT_SILENT_BREAKAWAY_OK flag set, on a Windows version
       * that doesn't support nested jobs.
       *
       * When that happens we just swallow the error and continue without
       * establishing a kill-child-on-parent-exit relationship, otherwise
       * there would be no way for libuv applications run under job control
       * to spawn processes at all.
       */
      DWORD err = GetLastError();
      if (err != ERROR_ACCESS_DENIED)
        uv_fatal_error(err, "AssignProcessToJobObject");
    }
  }

  /* Set IPC pid to all IPC pipes. */
  for (i = 0; i < options->stdio_count; i++) {
    const uv_stdio_container_t* fdopt = &options->stdio[i];
    if (fdopt->flags & UV_CREATE_PIPE &&
        fdopt->data.stream->type == UV_NAMED_PIPE &&
        ((uv_pipe_t*) fdopt->data.stream)->ipc) {
      ((uv_pipe_t*) fdopt->data.stream)->pipe.conn.ipc_remote_pid =
          info.dwProcessId;
    }
  }

  /* Setup notifications for when the child process exits. */
  result = RegisterWaitForSingleObject(&process->wait_handle,
      process->process_handle, exit_wait_callback, (void*)process, INFINITE,
      WT_EXECUTEINWAITTHREAD | WT_EXECUTEONLYONCE);
  if (!result) {
    uv_fatal_error(GetLastError(), "RegisterWaitForSingleObject");
  }

  CloseHandle(info.hThread);

  assert(!err);

  /* Make the handle active. It will remain active until the exit callback is
   * made or the handle is closed, whichever happens first. */
  uv__handle_start(process);

  /* Cleanup, whether we succeeded or failed. */
 done:
  uv__free(application);
  uv__free(application_path);
  uv__free(arguments);
  uv__free(cwd);
  uv__free(env);
  uv__free(alloc_path);

  if (process->child_stdio_buffer != NULL) {
    /* Clean up child stdio handles. */
    uv__stdio_destroy(process->child_stdio_buffer);
    process->child_stdio_buffer = NULL;
  }

  return uv_translate_sys_error(err);
}