diff options
Diffstat (limited to 'conf/mtab/mtab_isc3.c')
| -rw-r--r-- | conf/mtab/mtab_isc3.c | 269 |
1 files changed, 269 insertions, 0 deletions
diff --git a/conf/mtab/mtab_isc3.c b/conf/mtab/mtab_isc3.c new file mode 100644 index 000000000000..9c8df1bae7d8 --- /dev/null +++ b/conf/mtab/mtab_isc3.c @@ -0,0 +1,269 @@ +/* + * Copyright (c) 1997-2014 Erez Zadok + * Copyright (c) 1990 Jan-Simon Pendry + * Copyright (c) 1990 Imperial College of Science, Technology & Medicine + * Copyright (c) 1990 The Regents of the University of California. + * All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Jan-Simon Pendry at Imperial College, London. + * + * 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 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. + * + * + * File: am-utils/conf/mtab/mtab_isc3.c + * + */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif /* HAVE_CONFIG_H */ +#include <am_defs.h> +#include <amu.h> + +/* fd for /etc/.mnt.lock (also act as flag for: is_locked) */ +static int mtlckf = 0; +static char mtlckname[] = "/etc/.mnt.lock"; +static char mnttabname[] = "/etc/mnttab"; + + +static void +unlockmnttab(void) +{ + if (mtlckf) { + close(mtlckf); + mtlckf = 0; + } +} + + +static +lockfile(int fd, int type) +{ + struct flock lk; + + lk.l_type = type; + lk.l_whence = 0; + lk.l_start = 0; + lk.l_len = 0; + + return fcntl(fd, F_SETLKW, &lk); +} + + +static +lockmnttab(void) +{ + if (mtlckf == 0) { /* need lock on /etc/.mnt.lock */ + mtlckf = open(mtlckname, O_RDWR); + if (mtlckf >= 0) { + if (lockfile(mtlckf, F_WRLCK) < 0) { + close(mtlckf); + mtlckf = 0; +#ifdef DEBUG + dlog("lock failed %m"); +#endif /* DEBUG */ + } else { + return 0; + } + } + } + plog(XLOG_ERROR, "Unable to lock %s: %m", mtlckname); + return -1; +} + + +void +unlock_mntlist(void) +{ + dlog("unlock_mntlist: releasing"); + unlockmnttab(); +} + + +/* convert from ix386 mnttab to amd mntent */ +static mntent_t * +mnt_dup(mntent_t *mp) +{ + /* note: may not be null terminated */ + mntent_t *new_mp = ALLOC(mntent_t); + char nullcpy[128]; + + xstrlcpy(nullcpy, mp->mt_dev, 32); + new_mp->mnt_fsname = xstrdup(nullcpy); + + xstrlcpy(nullcpy, mp->mt_filsys, 32); + new_mp->mnt_dir = xstrdup(nullcpy); + + xstrlcpy(nullcpy, mp->mt_fstyp, 16); + new_mp->mnt_type = xstrdup(nullcpy); + + xstrlcpy(nullcpy, mp->mt_mntopts, 64); + new_mp->mnt_opts = xstrdup(nullcpy); + + new_mp->mnt_freq = 0; + new_mp->mnt_passno = 0; + + new_mp->mnt_time = mp->mt_time; + new_mp->mnt_ro = mp->mt_ro_flg; + + return new_mp; +} + + +/* convert back (static alloc) */ +static mntent_t * +mtab_of(mntent_t *mnt) +{ + static mntent_t mt; + + xstrlcpy(mt.mt_dev, mnt->mnt_fsname, 32); + xstrlcpy(mt.mt_filsys, mnt->mnt_dir, 32); + + mt.mt_ro_flg = mnt->mnt_ro; + mt.mt_time = mnt->mnt_time; + + xstrlcpy(mt.mt_fstyp, mnt->mnt_type, 16); + xstrlcpy(mt.mt_mntopts, mnt->mnt_opts, 64); + + return &mt; +} + + +/* + * Read a mount table into memory + */ +mntlist * +read_mtab(char *fs, const char *mnttabname) +{ + mntlist **mpp, *mhp; + /* From: Piete Brooks <pb@cl.cam.ac.uk> */ + int fd; + mntent_t mountbuffer[NMOUNT], *fs_data; + int ret; + int nmts; + + if (lockmnttab() != 0) + return (mntlist *) NULL; + + fd = open(mnttabname, O_RDONLY); + if (fd < 0) { + plog(XLOG_ERROR, "Can't open %s: %m", mnttabname); + return (mntlist *) NULL; + } + mpp = &mhp; + while ((ret = read(fd, (char *) mountbuffer, NMOUNT * sizeof(mntent_t))) > 0) { + nmts = ret / sizeof(mntent_t); + for (fs_data = mountbuffer; fs_data < &mountbuffer[nmts]; fs_data++) { + /* + * Allocate a new slot + */ + *mpp = ALLOC(struct mntlist); + + /* + * Copy the data returned by getmntent + */ + (*mpp)->mnt = mnt_dup(fs_data); + + /* + * Move to next pointer + */ + mpp = &(*mpp)->mnext; + } + } + if (ret < 0) { + plog(XLOG_ERROR, "read error on %s: %m", mnttabname); + unlockmnttab(); + mhp = (mntlist *) NULL; + } + *mpp = NULL; + + close(fd); + return mhp; +} + + +static +write_mntent_to_mtab(int fd, mntent_t *mnt) +{ + int wr; + +eagain: + wr = write(fd, (char *) mtab_of(mnt), sizeof(mntent_t)); + if (wr < 0) { + switch (wr) { + case EAGAIN: + goto eagain; + default: + return -1; + } + } + if (wr != sizeof(mntent_t)) + plog(XLOG_ERROR, "Can't write entry to %s: %m", mnttabname); + return 0; +} + + +void +rewrite_mtab(mntlist *mp, const char *mnttabname) +{ + int fd; + + assert(mtlckf != 0); + + fd = open(mnttabname, O_RDWR | O_TRUNC); + if (fd < 0) { + plog(XLOG_ERROR, "Can't open %s: %m", mnttabname); + unlockmnttab(); + } + while (mp) { + if (mp->mnt) + write_mntent_to_mtab(fd, mp->mnt); + mp = mp->mnext; + } + + close(fd); + unlockmnttab(); +} + + +void +write_mntent(mntent_t *mp, const char *mnttabname) +{ + int fd; + + if (lockmnttab() == -1) + return; + + fd = open(mnttabname, O_RDWR | O_APPEND); + if (fd < 0) { + plog(XLOG_ERROR, "Unable to append %s: %m", mnttabname); + return; + } + write_mntent_to_mtab(fd, mp); + + close(fd); + unlockmnttab(); +} |