[thirdparty/systemd.git] / src / shared / fstab-util.c

/* SPDX-License-Identifier: LGPL-2.1+ */

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>

#include "alloc-util.h"
#include "device-nodes.h"
#include "fstab-util.h"
#include "macro.h"
#include "mount-util.h"
#include "nulstr-util.h"
#include "parse-util.h"
#include "path-util.h"
#include "string-util.h"
#include "strv.h"

int fstab_has_fstype(const char *fstype) {
        _cleanup_endmntent_ FILE *f = NULL;
        struct mntent *m;

        f = setmntent(fstab_path(), "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;
}

bool fstab_is_extrinsic(const char *mount, const char *opts) {

        /* Don't bother with the OS data itself */
        if (PATH_IN_SET(mount,
                        "/",
                        "/usr",
                        "/etc"))
                return true;

        if (PATH_STARTSWITH_SET(mount,
                                "/run/initramfs",    /* This should stay around from before we boot until after we shutdown */
                                "/proc",             /* All of this is API VFS */
                                "/sys",              /* … dito … */
                                "/dev"))             /* … dito … */
                return true;

        /* If this is an initrd mount, and we are not in the initrd, then leave
         * this around forever, too. */
        if (opts && fstab_test_option(opts, "x-initrd.mount\0") && !in_initrd())
                return true;

        return false;
}

int fstab_is_mount_point(const char *mount) {
        _cleanup_endmntent_ FILE *f = NULL;
        struct mntent *m;

        f = setmntent(fstab_path(), "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 **ret_namefound, char **ret_value, char **ret_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 (!ret_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 (ret_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 occurrence found */
                        n = name;
                        if (ret_value) {
                                free(v);
                                if (*x == '\0')
                                        v = NULL;
                                else {
                                        assert(*x == '=');
                                        x++;
                                        v = strdup(x);
                                        if (!v)
                                                return -ENOMEM;
                                }
                        }
                }
                *t = NULL;
        }

answer:
        if (ret_namefound)
                *ret_namefound = n;
        if (ret_filtered) {
                char *f;

                f = strv_join(strv, ",");
                if (!f)
                        return -ENOMEM;

                *ret_filtered = f;
        }
        if (ret_value)
                *ret_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, 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_atoi(opt, &pri);
        if (r < 0)
                return r;

        *ret = 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);
}
Commit	Line	Data
53e1b683	1	/* SPDX-License-Identifier: LGPL-2.1+ */
d15d0333	2
a8fbdf54	3	#include <errno.h>
a8fbdf54 TA	4	#include <stdio.h>
a8fbdf54 TA	5	#include <stdlib.h>
a8fbdf54	6
b5efdb8a	7	#include "alloc-util.h"
6550203e	8	#include "device-nodes.h"
6bedfcbb	9	#include "fstab-util.h"
a8fbdf54	10	#include "macro.h"
4349cd7c	11	#include "mount-util.h"
d8b4d14d	12	#include "nulstr-util.h"
6bedfcbb	13	#include "parse-util.h"
0b6b6787	14	#include "path-util.h"
07630cea	15	#include "string-util.h"
d15d0333	16	#include "strv.h"
d15d0333	17
6c1921e9 FB	18	int fstab_has_fstype(const char *fstype) {
	19	_cleanup_endmntent_ FILE *f = NULL;
	20	struct mntent *m;
	21
ed4ad488	22	f = setmntent(fstab_path(), "re");
6c1921e9 FB	23	if (!f)
	24	return errno == ENOENT ? false : -errno;
	25
	26	for (;;) {
	27	errno = 0;
	28	m = getmntent(f);
	29	if (!m)
	30	return errno != 0 ? -errno : false;
	31
	32	if (streq(m->mnt_type, fstype))
	33	return true;
	34	}
	35	return false;
	36	}
	37
bc9e5a4c FB	38	bool fstab_is_extrinsic(const char mount, const char opts) {
	39
	40	/* Don't bother with the OS data itself */
	41	if (PATH_IN_SET(mount,
	42	"/",
	43	"/usr",
	44	"/etc"))
	45	return true;
	46
	47	if (PATH_STARTSWITH_SET(mount,
	48	"/run/initramfs", /* This should stay around from before we boot until after we shutdown */
	49	"/proc", /* All of this is API VFS */
	50	"/sys", /* … dito … */
	51	"/dev")) /* … dito … */
	52	return true;
	53
	54	/* If this is an initrd mount, and we are not in the initrd, then leave
	55	* this around forever, too. */
	56	if (opts && fstab_test_option(opts, "x-initrd.mount\0") && !in_initrd())
	57	return true;
	58
	59	return false;
	60	}
	61
b9088048	62	int fstab_is_mount_point(const char *mount) {
0b6b6787 KS	63	_cleanup_endmntent_ FILE *f = NULL;
	64	struct mntent *m;
	65
ed4ad488	66	f = setmntent(fstab_path(), "re");
0b6b6787	67	if (!f)
b9088048 FB	68	return errno == ENOENT ? false : -errno;
	69
	70	for (;;) {
	71	errno = 0;
	72	m = getmntent(f);
	73	if (!m)
	74	return errno != 0 ? -errno : false;
0b6b6787	75
0b6b6787 KS	76	if (path_equal(m->mnt_dir, mount))
0b6b6787 KS	77	return true;
b9088048	78	}
0b6b6787 KS	79	return false;
	80	}
	81
d15d0333	82	int fstab_filter_options(const char opts, const char names,
92a08691	83	const char ret_namefound, char ret_value, char **ret_filtered) {
d15d0333 ZJS	84	const char name, n = NULL, *x;
	85	_cleanup_strv_free_ char **stor = NULL;
	86	_cleanup_free_ char v = NULL, *strv = NULL;
	87
	88	assert(names && *names);
	89
	90	if (!opts)
	91	goto answer;
	92
	93	/* If !value and !filtered, this function is not allowed to fail. */
	94
92a08691	95	if (!ret_filtered) {
d15d0333 ZJS	96	const char word, state;
	97	size_t l;
	98
	99	FOREACH_WORD_SEPARATOR(word, l, opts, ",", state)
	100	NULSTR_FOREACH(name, names) {
	101	if (l < strlen(name))
	102	continue;
	103	if (!strneq(word, name, strlen(name)))
	104	continue;
	105
	106	/* we know that the string is NUL
	107	* terminated, so x is valid /
	108	x = word + strlen(name);
	109	if (IN_SET(*x, '\0', '=', ',')) {
	110	n = name;
92a08691	111	if (ret_value) {
d15d0333 ZJS	112	free(v);
	113	if (IN_SET(*x, '\0', ','))
	114	v = NULL;
	115	else {
	116	assert(*x == '=');
	117	x++;
	118	v = strndup(x, l - strlen(name) - 1);
	119	if (!v)
	120	return -ENOMEM;
	121	}
	122	}
	123	}
	124	}
	125	} else {
	126	char t, s;
	127
	128	stor = strv_split(opts, ",");
	129	if (!stor)
	130	return -ENOMEM;
	131	strv = memdup(stor, sizeof(char) (strv_length(stor) + 1));
	132	if (!strv)
	133	return -ENOMEM;
	134
	135	for (s = t = strv; *s; s++) {
	136	NULSTR_FOREACH(name, names) {
	137	x = startswith(*s, name);
	138	if (x && IN_SET(*x, '\0', '='))
	139	goto found;
	140	}
	141
	142	t = s;
	143	t++;
	144	continue;
	145	found:
5238e957	146	/* Keep the last occurrence found */
d15d0333	147	n = name;
92a08691	148	if (ret_value) {
d15d0333 ZJS	149	free(v);
	150	if (*x == '\0')
	151	v = NULL;
	152	else {
	153	assert(*x == '=');
	154	x++;
	155	v = strdup(x);
	156	if (!v)
	157	return -ENOMEM;
	158	}
	159	}
	160	}
	161	*t = NULL;
	162	}
	163
	164	answer:
92a08691 LP	165	if (ret_namefound)
	166	*ret_namefound = n;
	167	if (ret_filtered) {
d15d0333 ZJS	168	char *f;
	169
	170	f = strv_join(strv, ",");
	171	if (!f)
	172	return -ENOMEM;
	173
92a08691	174	*ret_filtered = f;
d15d0333	175	}
92a08691 LP	176	if (ret_value)
92a08691 LP	177	*ret_value = TAKE_PTR(v);
d15d0333 ZJS	178
	179	return !!n;
	180	}
	181
3519d230 KZ	182	int fstab_extract_values(const char opts, const char name, char ***values) {
	183	_cleanup_strv_free_ char optsv = NULL, res = NULL;
	184	char **s;
	185
	186	assert(opts);
	187	assert(name);
	188	assert(values);
	189
	190	optsv = strv_split(opts, ",");
	191	if (!optsv)
	192	return -ENOMEM;
	193
	194	STRV_FOREACH(s, optsv) {
	195	char *arg;
	196	int r;
	197
	198	arg = startswith(*s, name);
	199	if (!arg \|\| *arg != '=')
	200	continue;
	201	r = strv_extend(&res, arg + 1);
	202	if (r < 0)
	203	return r;
	204	}
	205
ae2a15bc	206	*values = TAKE_PTR(res);
3519d230 KZ	207
	208	return !!*values;
	209	}
	210
d15d0333 ZJS	211	int fstab_find_pri(const char options, int ret) {
d15d0333 ZJS	212	_cleanup_free_ char *opt = NULL;
7477451b	213	int r, pri;
d15d0333 ZJS	214
	215	assert(ret);
	216
	217	r = fstab_filter_options(options, "pri\0", NULL, &opt, NULL);
a75f4e2a	218	if (r < 0)
d15d0333	219	return r;
a75f4e2a ZJS	220	if (r == 0 \|\| !opt)
a75f4e2a ZJS	221	return 0;
d15d0333	222
7477451b	223	r = safe_atoi(opt, &pri);
d15d0333 ZJS	224	if (r < 0)
	225	return r;
	226
7477451b	227	*ret = pri;
d15d0333 ZJS	228	return 1;
d15d0333 ZJS	229	}
6550203e LP	230
	231	static char unquote(const char s, const char* quotes) {
	232	size_t l;
	233	assert(s);
	234
	235	/* This is rather stupid, simply removes the heading and
	236	* trailing quotes if there is one. Doesn't care about
	237	* escaping or anything.
	238	*
13e785f7	239	* DON'T USE THIS FOR NEW CODE ANYMORE! */
6550203e LP	240
	241	l = strlen(s);
	242	if (l < 2)
	243	return strdup(s);
	244
	245	if (strchr(quotes, s[0]) && s[l-1] == s[0])
	246	return strndup(s+1, l-2);
	247
	248	return strdup(s);
	249	}
	250
	251	static char tag_to_udev_node(const char tagvalue, const char *by) {
	252	_cleanup_free_ char t = NULL, u = NULL;
	253	size_t enc_len;
	254
	255	u = unquote(tagvalue, QUOTES);
	256	if (!u)
	257	return NULL;
	258
	259	enc_len = strlen(u) * 4 + 1;
	260	t = new(char, enc_len);
	261	if (!t)
	262	return NULL;
	263
	264	if (encode_devnode_name(u, t, enc_len) < 0)
	265	return NULL;
	266
605405c6	267	return strjoin("/dev/disk/by-", by, "/", t);
6550203e LP	268	}
	269
	270	char fstab_node_to_udev_node(const char p) {
	271	assert(p);
	272
	273	if (startswith(p, "LABEL="))
	274	return tag_to_udev_node(p+6, "label");
	275
	276	if (startswith(p, "UUID="))
	277	return tag_to_udev_node(p+5, "uuid");
	278
	279	if (startswith(p, "PARTUUID="))
	280	return tag_to_udev_node(p+9, "partuuid");
	281
	282	if (startswith(p, "PARTLABEL="))
	283	return tag_to_udev_node(p+10, "partlabel");
	284
	285	return strdup(p);
	286	}