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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 02:42:50 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 02:42:50 +0000 |
commit | 8cb83eee5a58b1fad74c34094ce3afb9e430b5a4 (patch) | |
tree | a9b2e7baeca1be40eb734371e3c8b11b02294497 /sys-utils/swapoff.c | |
parent | Initial commit. (diff) | |
download | util-linux-upstream/2.33.1.tar.xz util-linux-upstream/2.33.1.zip |
Adding upstream version 2.33.1.upstream/2.33.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | sys-utils/swapoff.c | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/sys-utils/swapoff.c b/sys-utils/swapoff.c new file mode 100644 index 0000000..0a3807f --- /dev/null +++ b/sys-utils/swapoff.c @@ -0,0 +1,253 @@ +#include <stdio.h> +#include <errno.h> +#include <getopt.h> + +#ifdef HAVE_SYS_SWAP_H +# include <sys/swap.h> +#endif + +#include "nls.h" +#include "c.h" +#include "xalloc.h" +#include "closestream.h" + +#include "swapprober.h" +#include "swapon-common.h" + +#if !defined(HAVE_SWAPOFF) && defined(SYS_swapoff) +# include <sys/syscall.h> +# define swapoff(path) syscall(SYS_swapoff, path) +#endif + +static int verbose; +static int all; + +#define QUIET 1 +#define CANONIC 1 + +/* + * This function works like mnt_resolve_tag(), but it's able to read UUID/LABEL + * from regular swap files too (according to entries in /proc/swaps). Note that + * mnt_resolve_tag() and mnt_resolve_spec() works with system visible block + * devices only. + */ +static char *swapoff_resolve_tag(const char *name, const char *value, + struct libmnt_cache *cache) +{ + char *path; + struct libmnt_table *tb; + struct libmnt_iter *itr; + struct libmnt_fs *fs; + + /* this is usual case for block devices (and it's really fast as it uses + * udev /dev/disk/by-* symlinks by default */ + path = mnt_resolve_tag(name, value, cache); + if (path) + return path; + + /* try regular files from /proc/swaps */ + tb = get_swaps(); + if (!tb) + return NULL; + + itr = mnt_new_iter(MNT_ITER_BACKWARD); + if (!itr) + err(EXIT_FAILURE, _("failed to initialize libmount iterator")); + + while (tb && mnt_table_next_fs(tb, itr, &fs) == 0) { + blkid_probe pr = NULL; + const char *src = mnt_fs_get_source(fs); + const char *type = mnt_fs_get_swaptype(fs); + const char *data = NULL; + + if (!src || !type || strcmp(type, "file") != 0) + continue; + pr = get_swap_prober(src); + if (!pr) + continue; + blkid_probe_lookup_value(pr, name, &data, NULL); + if (data && strcmp(data, value) == 0) + path = xstrdup(src); + blkid_free_probe(pr); + if (path) + break; + } + + mnt_free_iter(itr); + return path; +} + +static int do_swapoff(const char *orig_special, int quiet, int canonic) +{ + const char *special = orig_special; + + if (verbose) + printf(_("swapoff %s\n"), orig_special); + + if (!canonic) { + char *n, *v; + + special = mnt_resolve_spec(orig_special, mntcache); + if (!special && blkid_parse_tag_string(orig_special, &n, &v) == 0) { + special = swapoff_resolve_tag(n, v, mntcache); + free(n); + free(v); + } + if (!special) + return cannot_find(orig_special); + } + + if (swapoff(special) == 0) + return 0; /* success */ + + if (errno == EPERM) + errx(EXIT_FAILURE, _("Not superuser.")); + + if (!quiet || errno == ENOMEM) + warn(_("%s: swapoff failed"), orig_special); + + return -1; +} + +static int swapoff_by(const char *name, const char *value, int quiet) +{ + const char *special = swapoff_resolve_tag(name, value, mntcache); + return special ? do_swapoff(special, quiet, CANONIC) : cannot_find(value); +} + +static void __attribute__((__noreturn__)) usage(void) +{ + FILE *out = stdout; + fputs(USAGE_HEADER, out); + fprintf(out, _(" %s [options] [<spec>]\n"), program_invocation_short_name); + + fputs(USAGE_SEPARATOR, out); + fputs(_("Disable devices and files for paging and swapping.\n"), out); + + fputs(USAGE_OPTIONS, out); + fputs(_(" -a, --all disable all swaps from /proc/swaps\n" + " -v, --verbose verbose mode\n"), out); + + fputs(USAGE_SEPARATOR, out); + printf(USAGE_HELP_OPTIONS(24)); + + fputs(_("\nThe <spec> parameter:\n" \ + " -L <label> LABEL of device to be used\n" \ + " -U <uuid> UUID of device to be used\n" \ + " LABEL=<label> LABEL of device to be used\n" \ + " UUID=<uuid> UUID of device to be used\n" \ + " <device> name of device to be used\n" \ + " <file> name of file to be used\n"), out); + + printf(USAGE_MAN_TAIL("swapoff(8)")); + exit(EXIT_SUCCESS); +} + +static int swapoff_all(void) +{ + int status = 0; + struct libmnt_table *tb; + struct libmnt_fs *fs; + struct libmnt_iter *itr = mnt_new_iter(MNT_ITER_BACKWARD); + + if (!itr) + err(EXIT_FAILURE, _("failed to initialize libmount iterator")); + + /* + * In case /proc/swaps exists, unswap stuff listed there. We are quiet + * but report errors in status. Errors might mean that /proc/swaps + * exists as ordinary file, not in procfs. do_swapoff() exits + * immediately on EPERM. + */ + tb = get_swaps(); + + while (tb && mnt_table_find_next_fs(tb, itr, match_swap, NULL, &fs) == 0) + status |= do_swapoff(mnt_fs_get_source(fs), QUIET, CANONIC); + + /* + * Unswap stuff mentioned in /etc/fstab. Probably it was unmounted + * already, so errors are not bad. Doing swapoff -a twice should not + * give error messages. + */ + tb = get_fstab(); + mnt_reset_iter(itr, MNT_ITER_FORWARD); + + while (tb && mnt_table_find_next_fs(tb, itr, match_swap, NULL, &fs) == 0) { + if (!is_active_swap(mnt_fs_get_source(fs))) + do_swapoff(mnt_fs_get_source(fs), QUIET, !CANONIC); + } + + mnt_free_iter(itr); + return status; +} + +int main(int argc, char *argv[]) +{ + int status = 0, c; + size_t i; + + static const struct option long_opts[] = { + { "all", no_argument, NULL, 'a' }, + { "help", no_argument, NULL, 'h' }, + { "verbose", no_argument, NULL, 'v' }, + { "version", no_argument, NULL, 'V' }, + { NULL, 0, NULL, 0 } + }; + + setlocale(LC_ALL, ""); + bindtextdomain(PACKAGE, LOCALEDIR); + textdomain(PACKAGE); + atexit(close_stdout); + + while ((c = getopt_long(argc, argv, "ahvVL:U:", + long_opts, NULL)) != -1) { + switch (c) { + case 'a': /* all */ + ++all; + break; + case 'h': /* help */ + usage(); + break; + case 'v': /* be chatty */ + ++verbose; + break; + case 'V': /* version */ + printf(UTIL_LINUX_VERSION); + return EXIT_SUCCESS; + case 'L': + add_label(optarg); + break; + case 'U': + add_uuid(optarg); + break; + default: + errtryhelp(EXIT_FAILURE); + } + } + argv += optind; + + if (!all && !numof_labels() && !numof_uuids() && *argv == NULL) { + warnx(_("bad usage")); + errtryhelp(EXIT_FAILURE); + } + + mnt_init_debug(0); + mntcache = mnt_new_cache(); + + for (i = 0; i < numof_labels(); i++) + status |= swapoff_by("LABEL", get_label(i), !QUIET); + + for (i = 0; i < numof_uuids(); i++) + status |= swapoff_by("UUID", get_uuid(i), !QUIET); + + while (*argv != NULL) + status |= do_swapoff(*argv++, !QUIET, !CANONIC); + + if (all) + status |= swapoff_all(); + + free_tables(); + mnt_unref_cache(mntcache); + + return status; +} |