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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 02:42:50 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 02:42:50 +0000
commit8cb83eee5a58b1fad74c34094ce3afb9e430b5a4 (patch)
treea9b2e7baeca1be40eb734371e3c8b11b02294497 /libmount/src/optmap.c
parentInitial commit. (diff)
downloadutil-linux-8cb83eee5a58b1fad74c34094ce3afb9e430b5a4.tar.xz
util-linux-8cb83eee5a58b1fad74c34094ce3afb9e430b5a4.zip
Adding upstream version 2.33.1.upstream/2.33.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'libmount/src/optmap.c')
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1 files changed, 255 insertions, 0 deletions
diff --git a/libmount/src/optmap.c b/libmount/src/optmap.c
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+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * This file is part of libmount from util-linux project.
+ *
+ * Copyright (C) 2010-2018 Karel Zak <kzak@redhat.com>
+ *
+ * libmount 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.
+ */
+
+/**
+ * SECTION: optmap
+ * @title: Option maps
+ * @short_description: description for mount options
+ *
+ * The mount(2) linux syscall uses two arguments for mount options:
+ *
+ * @mountflags: (see MS_* macros in linux/fs.h)
+ *
+ * @mountdata: (usually a comma separated string of options)
+ *
+ * The libmount uses options-map(s) to describe mount options.
+ *
+ * The option description (map entry) includes:
+ *
+ * @name: and argument name
+ *
+ * @id: (in the map unique identifier or a mountflags, e.g MS_RDONLY)
+ *
+ * @mask: (MNT_INVERT, MNT_NOMTAB)
+ *
+ * The option argument value is defined by:
+ *
+ * "=" -- required argument, e.g "comment="
+ *
+ * "[=]" -- optional argument, e.g. "loop[=]"
+ *
+ * Example:
+ *
+ * <informalexample>
+ * <programlisting>
+ * #define MY_MS_FOO (1 << 1)
+ * #define MY_MS_BAR (1 << 2)
+ *
+ * libmnt_optmap myoptions[] = {
+ * { "foo", MY_MS_FOO },
+ * { "nofoo", MY_MS_FOO | MNT_INVERT },
+ * { "bar=", MY_MS_BAR },
+ * { NULL }
+ * };
+ * </programlisting>
+ * </informalexample>
+ *
+ * The libmount defines two basic built-in options maps:
+ *
+ * @MNT_LINUX_MAP: fs-independent kernel mount options (usually MS_* flags)
+ *
+ * @MNT_USERSPACE_MAP: userspace specific mount options (e.g. "user", "loop")
+ *
+ * For more details about option map struct see "struct mnt_optmap" in
+ * mount/mount.h.
+ */
+#include "mountP.h"
+#include "strutils.h"
+
+/*
+ * fs-independent mount flags (built-in MNT_LINUX_MAP)
+ */
+static const struct libmnt_optmap linux_flags_map[] =
+{
+ { "ro", MS_RDONLY }, /* read-only */
+ { "rw", MS_RDONLY, MNT_INVERT }, /* read-write */
+ { "exec", MS_NOEXEC, MNT_INVERT }, /* permit execution of binaries */
+ { "noexec", MS_NOEXEC }, /* don't execute binaries */
+ { "suid", MS_NOSUID, MNT_INVERT }, /* honor suid executables */
+ { "nosuid", MS_NOSUID }, /* don't honor suid executables */
+ { "dev", MS_NODEV, MNT_INVERT }, /* interpret device files */
+ { "nodev", MS_NODEV }, /* don't interpret devices */
+
+ { "sync", MS_SYNCHRONOUS }, /* synchronous I/O */
+ { "async", MS_SYNCHRONOUS, MNT_INVERT },/* asynchronous I/O */
+
+ { "dirsync", MS_DIRSYNC }, /* synchronous directory modifications */
+ { "remount", MS_REMOUNT, MNT_NOMTAB }, /* alter flags of mounted FS */
+ { "bind", MS_BIND }, /* Remount part of the tree elsewhere */
+ { "rbind", MS_BIND | MS_REC }, /* Idem, plus mounted subtrees */
+#ifdef MS_NOSUB
+ { "sub", MS_NOSUB, MNT_INVERT }, /* allow submounts */
+ { "nosub", MS_NOSUB }, /* don't allow submounts */
+#endif
+#ifdef MS_SILENT
+ { "silent", MS_SILENT }, /* be quiet */
+ { "loud", MS_SILENT, MNT_INVERT }, /* print out messages. */
+#endif
+#ifdef MS_MANDLOCK
+ { "mand", MS_MANDLOCK }, /* Allow mandatory locks on this FS */
+ { "nomand", MS_MANDLOCK, MNT_INVERT }, /* Forbid mandatory locks on this FS */
+#endif
+#ifdef MS_NOATIME
+ { "atime", MS_NOATIME, MNT_INVERT }, /* Update access time */
+ { "noatime", MS_NOATIME }, /* Do not update access time */
+#endif
+#ifdef MS_I_VERSION
+ { "iversion", MS_I_VERSION }, /* Update inode I_version time */
+ { "noiversion", MS_I_VERSION, MNT_INVERT},/* Don't update inode I_version time */
+#endif
+#ifdef MS_NODIRATIME
+ { "diratime", MS_NODIRATIME, MNT_INVERT }, /* Update dir access times */
+ { "nodiratime", MS_NODIRATIME }, /* Do not update dir access times */
+#endif
+#ifdef MS_RELATIME
+ { "relatime", MS_RELATIME }, /* Update access times relative to mtime/ctime */
+ { "norelatime", MS_RELATIME, MNT_INVERT }, /* Update access time without regard to mtime/ctime */
+#endif
+#ifdef MS_STRICTATIME
+ { "strictatime", MS_STRICTATIME }, /* Strict atime semantics */
+ { "nostrictatime", MS_STRICTATIME, MNT_INVERT }, /* kernel default atime */
+#endif
+#ifdef MS_LAZYTIME
+ { "lazytime", MS_LAZYTIME }, /* Update {a,m,c}time on the in-memory inode only */
+ { "nolazytime", MS_LAZYTIME, MNT_INVERT },
+#endif
+#ifdef MS_PROPAGATION
+ { "unbindable", MS_UNBINDABLE, MNT_NOHLPS | MNT_NOMTAB }, /* Unbindable */
+ { "runbindable", MS_UNBINDABLE | MS_REC, MNT_NOHLPS | MNT_NOMTAB },
+ { "private", MS_PRIVATE, MNT_NOHLPS | MNT_NOMTAB }, /* Private */
+ { "rprivate", MS_PRIVATE | MS_REC, MNT_NOHLPS | MNT_NOMTAB },
+ { "slave", MS_SLAVE, MNT_NOHLPS | MNT_NOMTAB }, /* Slave */
+ { "rslave", MS_SLAVE | MS_REC, MNT_NOHLPS | MNT_NOMTAB },
+ { "shared", MS_SHARED, MNT_NOHLPS | MNT_NOMTAB }, /* Shared */
+ { "rshared", MS_SHARED | MS_REC, MNT_NOHLPS | MNT_NOMTAB },
+#endif
+ { NULL, 0, 0 }
+};
+
+/*
+ * userspace mount option (built-in MNT_USERSPACE_MAP)
+ */
+static const struct libmnt_optmap userspace_opts_map[] =
+{
+ { "defaults", 0, 0 }, /* default options */
+
+ { "auto", MNT_MS_NOAUTO, MNT_NOHLPS | MNT_INVERT | MNT_NOMTAB }, /* Can be mounted using -a */
+ { "noauto", MNT_MS_NOAUTO, MNT_NOHLPS | MNT_NOMTAB }, /* Can only be mounted explicitly */
+
+ { "user[=]", MNT_MS_USER }, /* Allow ordinary user to mount (mtab) */
+ { "nouser", MNT_MS_USER, MNT_INVERT | MNT_NOMTAB }, /* Forbid ordinary user to mount */
+
+ { "users", MNT_MS_USERS, MNT_NOMTAB }, /* Allow ordinary users to mount */
+ { "nousers", MNT_MS_USERS, MNT_INVERT | MNT_NOMTAB }, /* Forbid ordinary users to mount */
+
+ { "owner", MNT_MS_OWNER, MNT_NOMTAB }, /* Let the owner of the device mount */
+ { "noowner", MNT_MS_OWNER, MNT_INVERT | MNT_NOMTAB }, /* Device owner has no special privs */
+
+ { "group", MNT_MS_GROUP, MNT_NOMTAB }, /* Let the group of the device mount */
+ { "nogroup", MNT_MS_GROUP, MNT_INVERT | MNT_NOMTAB }, /* Device group has no special privs */
+
+ /*
+ * Note that traditional init scripts assume the _netdev option in /etc/mtab to
+ * umount network block devices on shutdown.
+ */
+ { "_netdev", MNT_MS_NETDEV }, /* Device requires network */
+
+ { "comment=", MNT_MS_COMMENT, MNT_NOHLPS | MNT_NOMTAB },/* fstab comment only */
+
+ { "x-", MNT_MS_XCOMMENT, MNT_NOHLPS | MNT_PREFIX }, /* persistent comments (utab) */
+ { "X-", MNT_MS_XFSTABCOMM, MNT_NOHLPS | MNT_NOMTAB | MNT_PREFIX }, /* fstab only comments */
+
+ { "loop[=]", MNT_MS_LOOP, MNT_NOHLPS }, /* use the loop device */
+ { "offset=", MNT_MS_OFFSET, MNT_NOHLPS | MNT_NOMTAB }, /* loop device offset */
+ { "sizelimit=", MNT_MS_SIZELIMIT, MNT_NOHLPS | MNT_NOMTAB }, /* loop device size limit */
+ { "encryption=", MNT_MS_ENCRYPTION, MNT_NOHLPS | MNT_NOMTAB }, /* loop device encryption */
+
+ { "nofail", MNT_MS_NOFAIL, MNT_NOMTAB }, /* Do not fail if ENOENT on dev */
+
+ { "uhelper=", MNT_MS_UHELPER }, /* /sbin/umount.<helper> */
+
+ { "helper=", MNT_MS_HELPER }, /* /sbin/mount.<helper> */
+
+ { NULL, 0, 0 }
+};
+
+/**
+ * mnt_get_builtin_map:
+ * @id: map id -- MNT_LINUX_MAP or MNT_USERSPACE_MAP
+ *
+ * MNT_LINUX_MAP - Linux kernel fs-independent mount options
+ * (usually MS_* flags, see linux/fs.h)
+ *
+ * MNT_USERSPACE_MAP - userspace mount(8) specific mount options
+ * (e.g user=, _netdev, ...)
+ *
+ * Returns: static built-in libmount map.
+ */
+const struct libmnt_optmap *mnt_get_builtin_optmap(int id)
+{
+ assert(id);
+
+ if (id == MNT_LINUX_MAP)
+ return linux_flags_map;
+ else if (id == MNT_USERSPACE_MAP)
+ return userspace_opts_map;
+ return NULL;
+}
+
+/*
+ * Looks up the @name in @maps and returns a map and in @mapent
+ * returns the map entry
+ */
+const struct libmnt_optmap *mnt_optmap_get_entry(
+ struct libmnt_optmap const **maps,
+ int nmaps,
+ const char *name,
+ size_t namelen,
+ const struct libmnt_optmap **mapent)
+{
+ int i;
+
+ assert(maps);
+ assert(nmaps);
+ assert(name);
+ assert(namelen);
+
+ if (mapent)
+ *mapent = NULL;
+
+ for (i = 0; i < nmaps; i++) {
+ const struct libmnt_optmap *map = maps[i];
+ const struct libmnt_optmap *ent;
+ const char *p;
+
+ for (ent = map; ent && ent->name; ent++) {
+ if (ent->mask & MNT_PREFIX) {
+ if (startswith(name, ent->name)) {
+ if (mapent)
+ *mapent = ent;
+ return map;
+ }
+ continue;
+ }
+ if (strncmp(ent->name, name, namelen))
+ continue;
+ p = ent->name + namelen;
+ if (*p == '\0' || *p == '=' || *p == '[') {
+ if (mapent)
+ *mapent = ent;
+ return map;
+ }
+ }
+ }
+ return NULL;
+}
+