| /* 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/>. */ |
| |
| #include <support/capture_subprocess.h> |
| |
| #include <errno.h> |
| #include <stdlib.h> |
| #include <support/check.h> |
| #include <support/xunistd.h> |
| #include <support/xsocket.h> |
| |
| static void |
| transfer (const char *what, struct pollfd *pfd, struct xmemstream *stream) |
| { |
| if (pfd->revents != 0) |
| { |
| char buf[1024]; |
| ssize_t ret = TEMP_FAILURE_RETRY (read (pfd->fd, buf, sizeof (buf))); |
| if (ret < 0) |
| { |
| support_record_failure (); |
| printf ("error: reading from subprocess %s: %m", what); |
| pfd->events = 0; |
| pfd->revents = 0; |
| } |
| else if (ret == 0) |
| { |
| /* EOF reached. Stop listening. */ |
| pfd->events = 0; |
| pfd->revents = 0; |
| } |
| else |
| /* Store the data just read. */ |
| TEST_VERIFY (fwrite (buf, ret, 1, stream->out) == 1); |
| } |
| } |
| |
| struct support_capture_subprocess |
| support_capture_subprocess (void (*callback) (void *), void *closure) |
| { |
| struct support_capture_subprocess result; |
| xopen_memstream (&result.out); |
| xopen_memstream (&result.err); |
| |
| int stdout_pipe[2]; |
| xpipe (stdout_pipe); |
| int stderr_pipe[2]; |
| xpipe (stderr_pipe); |
| |
| TEST_VERIFY (fflush (stdout) == 0); |
| TEST_VERIFY (fflush (stderr) == 0); |
| |
| pid_t pid = xfork (); |
| if (pid == 0) |
| { |
| xclose (stdout_pipe[0]); |
| xclose (stderr_pipe[0]); |
| xdup2 (stdout_pipe[1], STDOUT_FILENO); |
| xdup2 (stderr_pipe[1], STDERR_FILENO); |
| callback (closure); |
| _exit (0); |
| } |
| xclose (stdout_pipe[1]); |
| xclose (stderr_pipe[1]); |
| |
| struct pollfd fds[2] = |
| { |
| { .fd = stdout_pipe[0], .events = POLLIN }, |
| { .fd = stderr_pipe[0], .events = POLLIN }, |
| }; |
| |
| do |
| { |
| xpoll (fds, 2, -1); |
| transfer ("stdout", &fds[0], &result.out); |
| transfer ("stderr", &fds[1], &result.err); |
| } |
| while (fds[0].events != 0 || fds[1].events != 0); |
| xclose (stdout_pipe[0]); |
| xclose (stderr_pipe[0]); |
| |
| xfclose_memstream (&result.out); |
| xfclose_memstream (&result.err); |
| xwaitpid (pid, &result.status, 0); |
| return result; |
| } |
| |
| void |
| support_capture_subprocess_free (struct support_capture_subprocess *p) |
| { |
| free (p->out.buffer); |
| free (p->err.buffer); |
| } |