spawn: Fix spawn_cb of gpgrt_spawn_process_fd.

* src/gpg-error.def.in (gpgrt_close_all_fds): New.
* src/gpg-error.vers (gpgrt_close_all_fds): New.
* src/gpg-error.h.in (GPGRT_SPAWN_INHERIT_FILE): New.
(gpgrt_spawn_process_fd): SPAWN_CB having return value.
* src/gpgrt-int.h (_gpgrt_spawn_process_fd): SPAWN_CB change.
* src/spawn-posix.c (_gpgrt_close_all_fds): Rename from close_all_fds,
and export it.
(do_exec): Support the case not closing fds.
(_gpgrt_spawn_process_fd): Handle return value of SPAWN_CB to
determine closing all fds or not.
* src/spawn-w32.c (_gpgrt_spawn_process_fd): Run SPAWN_CB.
(_gpgrt_close_all_fds): New.
* src/visibility.c (gpgrt_close_all_fds): New.
* src/visibility.h (gpgrt_close_all_fds): New.

--

Now, we have the API of gpgrt_spawn_process_fd for POSIX and Windows.
Giving portable semantics for spawning a process is difficult, and it
is still difficult for users to writing a function for SPAWN_CB with
portability, but gpgrt_spawn_process_fd gives the feature of spawning
a process.

GnuPG-bug-id: 6249
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>

1 files changed, 12 insertions, 5 deletions

diff --git a/src/gpgrt-int.h b/src/gpgrt-int.h
index b95b44c..c414272 100644
--- a/src/gpgrt-int.h
+++ b/src/gpgrt-int.h
@@ -696,15 +696,19 @@ _gpgrt_spawn_process (const char *pgmname, const char *argv[],
  * The arguments for the process are expected in the NULL terminated
  * array ARGV.  The program name itself should not be included there.
  * Calling gpgrt_wait_process and gpgrt_release_process is required.
- * Returns 0 on success or an error code.  If AFTER_FORK_CB is not
- * NULL, the given function will be called right after the fork, by
- * child process.
+ * Returns 0 on success or an error code.  If SPAWN_CB is not NULL,
+ * the given function will be called with SPAWN_CB_ARG to determine if
+ * file descriptors/handles should be inherited or not.  The callback
+ * function should return 1 to ask keeping file descriptors/handles.
+ * If SPAWN_CB is NULL, or it returns 0, all file descriptors (except
+ * INFD, OUTFD, and ERRFD) will be closed on POSIX machine.  On POSIX
+ * machine, it is called right after the fork, by child process.
  */
 gpg_err_code_t _gpgrt_spawn_process_fd (const char *pgmname,
                                         const char *argv[],
                                         int infd, int outfd, int errfd,
-                                        void (*after_fork_cb)(void *),
-                                        void *after_fork_cb_arg,
+                                        int (*spawn_cb) (void *),
+                                        void *spawn_cb_arg,
                                         pid_t *pid);
 
 /* Spawn a new process and immediately detach from it.  The name of
@@ -758,6 +762,9 @@ void _gpgrt_kill_process (pid_t pid);
  * It is a nop if PID is invalid.  */
 void _gpgrt_release_process (pid_t pid);
 
+/* Close all file resources (descriptors), except KEEP_FDS.  */
+void _gpgrt_close_all_fds (int from, int *keep_fds);
+
 
 /*
  * Local prototypes for argparse.