/* Capture output from a subprocess.

   Copyright (C) 2017-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#ifndef SUPPORT_CAPTURE_SUBPROCESS_H

#define SUPPORT_CAPTURE_SUBPROCESS_H

#include <support/xmemstream.h>

struct support_capture_subprocess

{

  struct xmemstream out;

  struct xmemstream err;

  int status;

};

/* Invoke CALLBACK (CLOSURE) in a subprocess and capture standard

   output, standard error, and the exit status.  The out.buffer and

   err.buffer members in the result are null-terminated strings which

   can be examined by the caller (out.out and err.out are NULL).  */

struct support_capture_subprocess support_capture_subprocess

  (void (*callback) (void *), void *closure);

/* Issue FILE with ARGV arguments by using posix_spawn and capture standard

   output, standard error, and the exit status.  The out.buffer and err.buffer

   are handle as support_capture_subprocess.  */

struct support_capture_subprocess support_capture_subprogram

  (const char *file, char *const argv[]);

/* Deallocate the subprocess data captured by

   support_capture_subprocess.  */

void support_capture_subprocess_free (struct support_capture_subprocess *);

enum support_capture_allow

{

  /* No output is allowed.  */

  sc_allow_none = 0x01,

  /* Output to stdout is permitted.  */

  sc_allow_stdout = 0x02,

  /* Output to standard error is permitted.  */

  sc_allow_stderr = 0x04,

};

/* Check that the subprocess exited and that only the allowed outputs

   happened.  If STATUS_OR_SIGNAL is nonnegative, it is the expected

   (decoded) exit status of the process, as returned by WEXITSTATUS.

   If STATUS_OR_SIGNAL is negative, -STATUS_OR_SIGNAL is the expected

   termination signal, as returned by WTERMSIG.  ALLOWED is a

   combination of support_capture_allow flags.  Report errors under

   the CONTEXT message.  */

void support_capture_subprocess_check (struct support_capture_subprocess *,

                                       const char *context,

                                       int status_or_signal, int allowed)

  __attribute__ ((nonnull (1, 2)));

#endif /* SUPPORT_CAPTURE_SUBPROCESS_H */