diff options
Diffstat (limited to 'third_party/heimdal/lib/roken/detach.c')
| -rw-r--r-- | third_party/heimdal/lib/roken/detach.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/roken/detach.c b/third_party/heimdal/lib/roken/detach.c new file mode 100644 index 00000000000..36e6cda1e02 --- /dev/null +++ b/third_party/heimdal/lib/roken/detach.c @@ -0,0 +1,225 @@ +/*- + * Copyright (c) 2015 + * Cryptonector LLC. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Cryptonector LLC may not be used to endorse or promote products + * derived from this software without specific prior written + * permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <config.h> +#include <errno.h> +#include <fcntl.h> +#ifdef WIN32 +#include <io.h> +#include <stdlib.h> +#else +#include <unistd.h> +#endif +#include "roken.h" + +#ifdef WIN32 +#define dup2 _dup2 +#endif + +static int pipefds[2] = {-1, -1}; + +ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL +roken_detach_prep(int argc, char **argv, char *special_arg) +{ + ssize_t bytes; + size_t i; + pid_t child; + char **new_argv; + char buf[1]; + char fildes[21]; + int status; + + pipefds[0] = -1; + pipefds[1] = -1; + +#ifdef WIN32 + if (_pipe(pipefds, 4, _O_NOINHERIT | O_BINARY) == -1) + err(1, "failed to setup to detach daemon (_pipe failed)"); +#else + if (pipe(pipefds) == -1) + err(1, "failed to setup to detach daemon (pipe failed)"); +#endif + + new_argv = calloc(argc + 3, sizeof(*new_argv)); + if (new_argv == NULL) + err(1, "Out of memory"); + +#ifdef WIN32 + pipefds[1] = _dup(pipefds[1]); /* The new fd will be inherited */ + if (pipefds[1] == -1) + err(1, "Out of memory"); +#else + fcntl(pipefds[1], F_SETFD, fcntl(pipefds[1], F_GETFD & ~(O_CLOEXEC))); +#endif + + if (snprintf(fildes, sizeof(fildes), "%d", pipefds[1]) >= sizeof(fildes)) + err(1, "failed to setup to detach daemon (fd number %d too large)", + pipefds[1]); + + new_argv[0] = argv[0]; + new_argv[1] = special_arg; + new_argv[2] = fildes; + for (i = 1; argv[i] != NULL; i++) + new_argv[i + 2] = argv[i]; + new_argv[argc + 2] = NULL; + +#ifndef WIN32 + fflush(stdout); + child = fork(); +#else + { + intptr_t child_handle; + + _flushall(); + child_handle = spawnvp(_P_NOWAIT, argv[0], new_argv); + if (child_handle == -1) + child = (pid_t)-1; + else + child = GetProcessId((HANDLE)child_handle); + } +#endif + if (child == (pid_t)-1) + err(1, "failed to setup to fork daemon (fork failed)"); + +#ifndef WIN32 + if (child == 0) { + int fd; + + (void) close(pipefds[0]); + pipefds[0] = -1; + /* + * Keep stdout/stderr for now so output and errors prior to + * detach_finish() can be seen by the user. + */ + fd = open(_PATH_DEVNULL, O_RDWR, 0); + if (fd == -1) + err(1, "failed to open /dev/null"); + (void) dup2(fd, STDIN_FILENO); + if (fd > STDERR_FILENO) + (void) close(fd); + if (getenv("ROKEN_DETACH_USE_EXEC")) { + (void) execvp(argv[0], new_argv); + err(1, "failed to self-re-exec"); + } + free(new_argv); + return pipefds[1]; + } +#endif + + /* Parent */ + free(new_argv); + (void) close(pipefds[1]); + pipefds[1] = -1; + do { + bytes = read(pipefds[0], buf, sizeof(buf)); + } while (bytes == -1 && errno == EINTR); + (void) close(pipefds[0]); + pipefds[0] = -1; + if (bytes == -1) { + /* + * No need to wait for the process. We've killed it. If it + * doesn't want to exit, we'd have to wait potentially forever, + * but we want to indicate failure to the user as soon as + * possible. A wait with timeout would end the same way + * (attempting to kill the process). + */ + err(1, "failed to setup daemon child (read from child pipe)"); + } + if (bytes == 0) { + warnx("daemon child preparation failed, waiting for child"); + status = wait_for_process(child); + if (SE_IS_ERROR(status) || SE_PROCSTATUS(status) != 0) + errx(SE_PROCSTATUS(status), + "daemon child preparation failed (child exited)"); + } + _exit(0); + /* NOTREACHED */ + return -1; +} + +#ifdef WIN32 +#ifdef dup2 +#undef dup2 +#endif +#define dup2 _dup2 +#endif + +ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL +roken_detach_finish(const char *dir, int daemon_child_fd) +{ + char buf[1] = ""; + ssize_t bytes; + int fd; + + rk_pidfile(NULL); + if (pipefds[1] == -1 && daemon_child_fd != -1) + pipefds[1] = daemon_child_fd; + if (pipefds[0] != -1) + (void) close(pipefds[0]); + if (pipefds[1] == -1) + return; + +#ifdef HAVE_SETSID + if (setsid() == -1) + err(1, "failed to detach from tty"); +#endif + +#ifndef WIN32 + /* + * Hopefully we've written any pidfiles by now, if they had to be in + * the current directory... + * + * The daemons do re-open logs and so on, therefore this chdir() + * call needs to be optional for testing. + */ + if (dir != NULL && chdir(dir) == -1) + err(1, "failed to chdir to /"); +#endif + + do { + bytes = write(pipefds[1], buf, sizeof(buf)); + } while (bytes == -1 && errno == EINTR); + if (bytes == -1) + err(1, "failed to signal parent while detaching"); + (void) close(pipefds[1]); + if (bytes != sizeof(buf)) + errx(1, "failed to signal parent while detaching"); + + fd = open(_PATH_DEVNULL, O_RDWR, 0); + if (fd == -1) + err(1, "failed to open /dev/null"); + /* + * Maybe we should check that our output got written, if redirected + * to a file. File utils normally do this. + */ + (void) dup2(fd, STDOUT_FILENO); + (void) dup2(fd, STDERR_FILENO); + if (fd > 2) + (void) close(fd); +} |