w32: Synchronous spawning gpg-agent/dirmngr/keyboxd.gniibe/synch-spawn

* common/asshelp.h [HAVE_W32_SYSTEM] (w32_ack_to_frontend): New.
* common/asshelp.c [HAVE_W32_SYSTEM] (start_new_service): Use
GPGRT_PROCESS_STDOUT_PIPE flag, and read from the pipe to wait.
(w32_ack_to_frontend): New.
* agent/gpg-agent.c [HAVE_W32_SYSTEM] (main): Add
w32_ack_to_frontend.
* dirmngr/dirmngr.c [HAVE_W32_SYSTEM] (main): Likewise.
* kbx/keyboxd.c [HAVE_W32_SYSTEM] (main): Likewise.

--

GnuPG-bug-id: 7720
Signed-off-by: NIIBE Yutaka <[email protected]>

5 files changed, 84 insertions, 1 deletions

diff --git a/agent/gpg-agent.c b/agent/gpg-agent.c
index ae1295977..9d214e703 100644
--- a/agent/gpg-agent.c
+++ b/agent/gpg-agent.c
@@ -1855,6 +1855,9 @@ main (int argc, char **argv)
         }
 
       log_info ("%s %s started\n", gpgrt_strusage(11), gpgrt_strusage(13) );
+#ifdef HAVE_W32_SYSTEM
+      w32_ack_to_frontend ();
+#endif
       handle_connections (fd, fd_extra, fd_browser, fd_ssh,
                           reliable_homedir_inotify);
       assuan_sock_close (fd);
diff --git a/common/asshelp.c b/common/asshelp.c
index 0152d1243..a45f05714 100644
--- a/common/asshelp.c
+++ b/common/asshelp.c
@@ -536,8 +536,46 @@ start_new_service (assuan_context_t *r_ctx,
           && assuan_socket_connect (ctx, sockname, 0, connect_flags))
         {
 #ifdef HAVE_W32_SYSTEM
+          gpgrt_process_t proc;
+
           err = gpgrt_process_spawn (program? program : program_name, argv,
-                                     GPGRT_PROCESS_DETACHED, NULL, NULL);
+                                     (GPGRT_PROCESS_DETACHED
+                                      |GPGRT_PROCESS_STDOUT_PIPE
+                                      |GPGRT_PROCESS_STDERR_KEEP),
+                                     NULL, &proc);
+          if (!err)
+            {
+              int pipe_in;
+              err = gpgrt_process_get_fds (proc, 0, NULL, &pipe_in, NULL);
+              if (!err)
+                {
+                  char buf[256];
+                  int r;
+
+                  /* We wait until the child process says it's ready
+                     to serve, by reading from the pipe.  */
+                  r = read (pipe_in, buf, sizeof buf);
+                  close (pipe_in);
+                  /* Older versions of Windows (< Vista), it cannot
+                   * support spawing with pipe I/O for
+                   * GPGRT_PROCESS_DETACHED flag (since inheriting
+                   * specific HANDLEs are not supported).  In this
+                   * case, read from child process fails.
+                   */
+                  if (r < 0)
+                    {
+                      if (verbose)
+                        log_info ("read from child process failed: %s\n",
+                                  strerror (errno));
+/* NOTE: Remove following line when we can assume newer Windows.  */
+#define SUPPORT_OLDER_WINDOWS 1
+#if !defined(SUPPORT_OLDER_WINDOWS)
+                      err = gpg_error (GPG_ERR_SERVER_FAILED);
+#endif
+                    }
+                }
+              gpgrt_process_release (proc);
+            }
 #else /*!W32*/
           err = gpgrt_process_spawn (program? program : program_name, argv,
                                      0, NULL, NULL);
@@ -757,3 +795,38 @@ warn_server_version_mismatch (assuan_context_t ctx,
   xfree (serverversion);
   return err;
 }
+
+
+#ifdef HAVE_W32_SYSTEM
+#include <fcntl.h>
+
+/*
+ * At the start of service (gpg-agent/dirmngr/keyboxd), after the
+ * preparation of socket, send "OK" (or "ERR 1") to the frontend
+ * (gpg/gpgsm).
+ */
+void
+w32_ack_to_frontend (void)
+{
+  int null_fd = open ("NUL", O_RDWR);
+
+  /* For the case of older Windows (< Vista), stdin/stdout/stder is
+   * invalid handle and write to stdout may fail.  We ignore this
+   * error.  */
+  if (null_fd < 0)
+    {
+      perror ("open failed");
+      /* Reply "General Error".  */
+      write (1, "ERR 1\n", 6);
+    }
+  else
+    {
+      /* Reply, it's OK.  */
+      write (1, "OK\n", 3);
+      if (dup2 (null_fd, 1) < 0)
+        perror ("dup2 failed");
+      dup2 (null_fd, 2);
+      close (null_fd);
+    }
+}
+#endif
diff --git a/common/asshelp.h b/common/asshelp.h
index cde6e226f..936a3964e 100644
--- a/common/asshelp.h
+++ b/common/asshelp.h
@@ -106,6 +106,11 @@ gpg_error_t warn_server_version_mismatch (assuan_context_t ctx,
                                           void *status_func_ctrl,
                                           int print_hints);
 
+#ifdef HAVE_W32_SYSTEM
+/* Say hello to the frontend.  */
+void w32_ack_to_frontend (void);
+#endif
+
 
 /*-- asshelp2.c --*/
 
diff --git a/dirmngr/dirmngr.c b/dirmngr/dirmngr.c
index d418d09e2..dc7e233f2 100644
--- a/dirmngr/dirmngr.c
+++ b/dirmngr/dirmngr.c
@@ -1526,6 +1526,7 @@ main (int argc, char **argv)
       pid = getpid ();
       es_printf ("set %s=%s;%lu;1\n",
                  DIRMNGR_INFO_NAME, socket_name, (ulong) pid);
+      w32_ack_to_frontend ();
 #else
       pid = fork();
       if (pid == (pid_t)-1)
diff --git a/kbx/keyboxd.c b/kbx/keyboxd.c
index 197f01c74..4eff1cc45 100644
--- a/kbx/keyboxd.c
+++ b/kbx/keyboxd.c
@@ -734,6 +734,7 @@ main (int argc, char **argv )
 
       (void)nodetach;
       initialize_modules ();
+      w32_ack_to_frontend ();
 
 #else /*!HAVE_W32_SYSTEM*/