diff options
Diffstat (limited to 'support')
| -rw-r--r-- | support/include/nfslib.h | 4 | ||||
| -rw-r--r-- | support/nfs/Makefile.am | 2 | ||||
| -rw-r--r-- | support/nfs/mydaemon.c | 148 |
3 files changed, 153 insertions, 1 deletions
diff --git a/support/include/nfslib.h b/support/include/nfslib.h index f210a06..ce4b14b 100644 --- a/support/include/nfslib.h +++ b/support/include/nfslib.h @@ -128,6 +128,10 @@ void fputrmtabent(FILE *fp, struct rmtabent *xep, long *pos); void fendrmtabent(FILE *fp); void frewindrmtabent(FILE *fp); +/* mydaemon */ +void mydaemon(int nochdir, int noclose, int *pipefds); +void release_parent(int *pipefds); + /* * wildmat borrowed from INN */ diff --git a/support/nfs/Makefile.am b/support/nfs/Makefile.am index 05c2fc4..fb9b8c1 100644 --- a/support/nfs/Makefile.am +++ b/support/nfs/Makefile.am @@ -2,7 +2,7 @@ noinst_LIBRARIES = libnfs.a libnfs_a_SOURCES = exports.c rmtab.c xio.c rpcmisc.c rpcdispatch.c \ - xlog.c xcommon.c wildmat.c nfsclient.c \ + xlog.c xcommon.c wildmat.c mydaemon.c nfsclient.c \ nfsexport.c getfh.c nfsctl.c rpc_socket.c getport.c \ svc_socket.c cacheio.c closeall.c nfs_mntent.c conffile.c \ svc_create.c atomicio.c strlcpy.c strlcat.c diff --git a/support/nfs/mydaemon.c b/support/nfs/mydaemon.c new file mode 100644 index 0000000..e885d60 --- /dev/null +++ b/support/nfs/mydaemon.c @@ -0,0 +1,148 @@ +/* + mydaemon.c + + Copyright (c) 2000 The Regents of the University of Michigan. + All rights reserved. + + Copyright (c) 2000 Dug Song <dugsong@UMICH.EDU>. + Copyright (c) 2002 Andy Adamson <andros@UMICH.EDU>. + Copyright (c) 2002 Marius Aamodt Eriksen <marius@UMICH.EDU>. + Copyright (c) 2002 J. Bruce Fields <bfields@UMICH.EDU>. + Copyright (c) 2013 Jeff Layton <jlayton@redhat.com> + + All rights reserved, all wrongs reversed. + + 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. Neither the name of the University nor the names of its + contributors may be used to endorse or promote products derived + from this software without specific prior written permission. + + THIS SOFTWARE IS PROVIDED ``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 <sys/param.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <errno.h> +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <xlog.h> + +/** + * mydaemon - daemonize, but have parent wait to exit + * @nochdir: skip chdir()'ing the child to / after forking if true + * @noclose: skip closing stdin/stdout/stderr if true + * @pipefds: pointer to 2 element array of pipefds + * + * This function is like daemon(), but with our own special sauce to delay + * the exit of the parent until the child is set up properly. A pipe is created + * between parent and child. The parent process will wait to exit until the + * child dies or writes a '1' on the pipe signaling that it started + * successfully. + */ +void +mydaemon(int nochdir, int noclose, int *pipefds) +{ + int pid, status, tempfd; + + if (pipe(pipefds) < 0) { + xlog_err("mydaemon: pipe() failed: errno %d (%s)\n", + errno, strerror(errno)); + exit(1); + } + if ((pid = fork ()) < 0) { + xlog_err("mydaemon: fork() failed: errno %d (%s)\n", + errno, strerror(errno)); + exit(1); + } + + if (pid != 0) { + /* + * Parent. Wait for status from child. + */ + close(pipefds[1]); + if (read(pipefds[0], &status, 1) != 1) + exit(1); + exit (0); + } + /* Child. */ + close(pipefds[0]); + setsid (); + if (nochdir == 0) { + if (chdir ("/") == -1) { + xlog_err("mydaemon: chdir() failed: errno %d (%s)\n", + errno, strerror(errno)); + exit(1); + } + } + + while (pipefds[1] <= 2) { + pipefds[1] = dup(pipefds[1]); + if (pipefds[1] < 0) { + xlog_err("mydaemon: dup() failed: errno %d (%s)\n", + errno, strerror(errno)); + exit(1); + } + } + + if (noclose == 0) { + tempfd = open("/dev/null", O_RDWR); + if (tempfd >= 0) { + dup2(tempfd, 0); + dup2(tempfd, 1); + dup2(tempfd, 2); + close(tempfd); + } else { + xlog_err("mydaemon: can't open /dev/null: errno %d " + "(%s)\n", errno, strerror(errno)); + exit(1); + } + } + + return; +} + +/** + * release_parent - tell the parent that it can exit now + * @pipefds: pipefd array that was previously passed to mydaemon() + * + * This function tells the parent process of mydaemon() that it's now clear + * to exit(0). + */ +void +release_parent(int *pipefds) +{ + int status; + + if (pipefds[1] > 0) { + if (write(pipefds[1], &status, 1) != 1) { + xlog_err("WARN: writing to parent pipe failed: errno " + "%d (%s)\n", errno, strerror(errno)); + } + close(pipefds[1]); + pipefds[1] = -1; + } +} + |