diff options
Diffstat (limited to 'src/shared/fstab-util.c')
| -rw-r--r-- | src/shared/fstab-util.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/src/shared/fstab-util.c b/src/shared/fstab-util.c new file mode 100644 index 0000000..6fd9866 --- /dev/null +++ b/src/shared/fstab-util.c @@ -0,0 +1,268 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <errno.h> +#include <mntent.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "alloc-util.h" +#include "device-nodes.h" +#include "fstab-util.h" +#include "macro.h" +#include "mount-util.h" +#include "parse-util.h" +#include "path-util.h" +#include "string-util.h" +#include "strv.h" +#include "util.h" + +int fstab_has_fstype(const char *fstype) { + _cleanup_endmntent_ FILE *f = NULL; + struct mntent *m; + + f = setmntent("/etc/fstab", "re"); + if (!f) + return errno == ENOENT ? false : -errno; + + for (;;) { + errno = 0; + m = getmntent(f); + if (!m) + return errno != 0 ? -errno : false; + + if (streq(m->mnt_type, fstype)) + return true; + } + return false; +} + +int fstab_is_mount_point(const char *mount) { + _cleanup_endmntent_ FILE *f = NULL; + struct mntent *m; + + f = setmntent("/etc/fstab", "re"); + if (!f) + return errno == ENOENT ? false : -errno; + + for (;;) { + errno = 0; + m = getmntent(f); + if (!m) + return errno != 0 ? -errno : false; + + if (path_equal(m->mnt_dir, mount)) + return true; + } + return false; +} + +int fstab_filter_options(const char *opts, const char *names, + const char **namefound, char **value, char **filtered) { + const char *name, *n = NULL, *x; + _cleanup_strv_free_ char **stor = NULL; + _cleanup_free_ char *v = NULL, **strv = NULL; + + assert(names && *names); + + if (!opts) + goto answer; + + /* If !value and !filtered, this function is not allowed to fail. */ + + if (!filtered) { + const char *word, *state; + size_t l; + + FOREACH_WORD_SEPARATOR(word, l, opts, ",", state) + NULSTR_FOREACH(name, names) { + if (l < strlen(name)) + continue; + if (!strneq(word, name, strlen(name))) + continue; + + /* we know that the string is NUL + * terminated, so *x is valid */ + x = word + strlen(name); + if (IN_SET(*x, '\0', '=', ',')) { + n = name; + if (value) { + free(v); + if (IN_SET(*x, '\0', ',')) + v = NULL; + else { + assert(*x == '='); + x++; + v = strndup(x, l - strlen(name) - 1); + if (!v) + return -ENOMEM; + } + } + } + } + } else { + char **t, **s; + + stor = strv_split(opts, ","); + if (!stor) + return -ENOMEM; + strv = memdup(stor, sizeof(char*) * (strv_length(stor) + 1)); + if (!strv) + return -ENOMEM; + + for (s = t = strv; *s; s++) { + NULSTR_FOREACH(name, names) { + x = startswith(*s, name); + if (x && IN_SET(*x, '\0', '=')) + goto found; + } + + *t = *s; + t++; + continue; + found: + /* Keep the last occurence found */ + n = name; + if (value) { + free(v); + if (*x == '\0') + v = NULL; + else { + assert(*x == '='); + x++; + v = strdup(x); + if (!v) + return -ENOMEM; + } + } + } + *t = NULL; + } + +answer: + if (namefound) + *namefound = n; + if (filtered) { + char *f; + + f = strv_join(strv, ","); + if (!f) + return -ENOMEM; + + *filtered = f; + } + if (value) + *value = TAKE_PTR(v); + + return !!n; +} + +int fstab_extract_values(const char *opts, const char *name, char ***values) { + _cleanup_strv_free_ char **optsv = NULL, **res = NULL; + char **s; + + assert(opts); + assert(name); + assert(values); + + optsv = strv_split(opts, ","); + if (!optsv) + return -ENOMEM; + + STRV_FOREACH(s, optsv) { + char *arg; + int r; + + arg = startswith(*s, name); + if (!arg || *arg != '=') + continue; + r = strv_extend(&res, arg + 1); + if (r < 0) + return r; + } + + *values = TAKE_PTR(res); + + return !!*values; +} + +int fstab_find_pri(const char *options, int *ret) { + _cleanup_free_ char *opt = NULL; + int r; + unsigned pri; + + assert(ret); + + r = fstab_filter_options(options, "pri\0", NULL, &opt, NULL); + if (r < 0) + return r; + if (r == 0 || !opt) + return 0; + + r = safe_atou(opt, &pri); + if (r < 0) + return r; + + if ((int) pri < 0) + return -ERANGE; + + *ret = (int) pri; + return 1; +} + +static char *unquote(const char *s, const char* quotes) { + size_t l; + assert(s); + + /* This is rather stupid, simply removes the heading and + * trailing quotes if there is one. Doesn't care about + * escaping or anything. + * + * DON'T USE THIS FOR NEW CODE ANYMORE! */ + + l = strlen(s); + if (l < 2) + return strdup(s); + + if (strchr(quotes, s[0]) && s[l-1] == s[0]) + return strndup(s+1, l-2); + + return strdup(s); +} + +static char *tag_to_udev_node(const char *tagvalue, const char *by) { + _cleanup_free_ char *t = NULL, *u = NULL; + size_t enc_len; + + u = unquote(tagvalue, QUOTES); + if (!u) + return NULL; + + enc_len = strlen(u) * 4 + 1; + t = new(char, enc_len); + if (!t) + return NULL; + + if (encode_devnode_name(u, t, enc_len) < 0) + return NULL; + + return strjoin("/dev/disk/by-", by, "/", t); +} + +char *fstab_node_to_udev_node(const char *p) { + assert(p); + + if (startswith(p, "LABEL=")) + return tag_to_udev_node(p+6, "label"); + + if (startswith(p, "UUID=")) + return tag_to_udev_node(p+5, "uuid"); + + if (startswith(p, "PARTUUID=")) + return tag_to_udev_node(p+9, "partuuid"); + + if (startswith(p, "PARTLABEL=")) + return tag_to_udev_node(p+10, "partlabel"); + + return strdup(p); +} |