libmount: (optlist) extend functionality

* remember MS_REMOUNT and add mnt_optlist_is_remount()

* fix opt->external use

* add possibility to filter options for mnt_optlist_get_*()

* allow to set/get values

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libmount/src/mountP.h b/libmount/src/mountP.h
index d2e371ceb8acad790393b08b8a2de7ada7ee3817..008fff161d5e658956ca8a11368ebcc64bccb454 100644 (file)
--- a/libmount/src/mountP.h
+++ b/libmount/src/mountP.h
@@ -509,15 +509,30 @@ extern int mnt_optlist_insert_flags(struct libmnt_optlist *ls, unsigned long fla
                         const struct libmnt_optmap *map,
                         unsigned long after,
                         const struct libmnt_optmap *after_map);
+/* "what" argument */
+enum {
+       MNT_OPTLIST_DEFAULT = 0,        /* all (including uknonwn), but exclude external options */
+       MNT_OPTLIST_UNKNOWN = (1 << 1), /* only uknonwn options */
+       MNT_OPTLIST_EXTERNAL = (1 << 2) /* include also external options */
+};
+
 extern int mnt_optlist_get_flags(struct libmnt_optlist *ls, unsigned long *flags,
-                          const struct libmnt_optmap *map);
+                          const struct libmnt_optmap *map, unsigned int what);
 extern int mnt_optlist_get_optstr(struct libmnt_optlist *ol, const char **optstr,
-                        const struct libmnt_optmap *map);
+                        const struct libmnt_optmap *map, unsigned int what);
+
 extern int mnt_optlist_get_propagation(struct libmnt_optlist *ls);
 extern int mnt_optlist_is_propagation_only(struct libmnt_optlist *ls);
+extern int mnt_optlist_is_remount(struct libmnt_optlist *ls);
+extern int mnt_optlist_merge_opts(struct libmnt_optlist *ls);
+
 extern int mnt_opt_has_value(struct libmnt_opt *opt);
+extern const char *mnt_opt_get_value(struct libmnt_opt *opt);
+extern const char *mnt_opt_get_name(struct libmnt_opt *opt);
 extern int mnt_opt_set_external(struct libmnt_opt *opt, int enable);
-extern int mnt_optlist_merge_opts(struct libmnt_optlist *ls);
+extern int mnt_opt_set_value(struct libmnt_opt *opt, const char *str);
+extern int mnt_opt_set_u64value(struct libmnt_opt *opt, uint64_t num);
+extern int mnt_opt_set_quoted_value(struct libmnt_opt *opt, const char *str);
 
 
 /* fs.c */

diff --git a/libmount/src/optlist.c b/libmount/src/optlist.c
index 7a71d821467ff05095d2f9585699ca4def1a78a3..a85a8eeec3e6603604e1e4e51a183f200936c18c 100644 (file)
--- a/libmount/src/optlist.c
+++ b/libmount/src/optlist.c
@@ -47,11 +47,13 @@ struct libmnt_optlist {
 
        char *cached_str[MNT_OPTLIST_MAXMAPS];
        char *cached_all;
+       char *cached_unknown;
 
        unsigned long           propagation;    /* propagation MS_ flags */
        struct list_head        opts;           /* parsed options */
 
-       unsigned int merged : 1;                /* don't care about MNT_OPTSRC_* */
+       unsigned int merged : 1,                /* don't care about MNT_OPTSRC_* */
+                    remount : 1;
 };
 
 struct libmnt_optlist *mnt_new_optlist(void)
@@ -99,6 +101,7 @@ void mnt_unref_optlist(struct libmnt_optlist *ls)
                free(ls->cached_str[i]);
 
        free(ls->cached_all);
+       free(ls->cached_unknown);
        free(ls);
 }
 
@@ -143,6 +146,7 @@ static void optlist_cleanup_cached(struct libmnt_optlist *ls, const struct libmn
        free(ls->cached_all);
        ls->cached_all = NULL;
 
+
        if (map) {
                size_t idx = optlist_get_mapidx(ls, map);
 
@@ -151,7 +155,11 @@ static void optlist_cleanup_cached(struct libmnt_optlist *ls, const struct libmn
 
                free(ls->cached_str[idx]);
                ls->cached_str[idx] = NULL;
+       } else {
+               free(ls->cached_unknown);
+               ls->cached_unknown = NULL;
        }
+
 }
 
 int mnt_optlist_remove_opt(struct libmnt_optlist *ls, struct libmnt_opt *opt)
@@ -160,9 +168,13 @@ int mnt_optlist_remove_opt(struct libmnt_optlist *ls, struct libmnt_opt *opt)
                return -EINVAL;
 
        DBG(OPTLIST, ul_debugobj(ls, " remove %s", opt->name));
-       if (opt->map && opt->ent
-           && opt->map == ls->linux_map && opt->ent->id & MS_PROPAGATION)
-               ls->propagation &= ~opt->ent->id;
+
+       if (opt->map && opt->ent && opt->map == ls->linux_map) {
+               if (opt->ent->id & MS_PROPAGATION)
+                       ls->propagation &= ~opt->ent->id;
+               else if (opt->ent->id == MS_REMOUNT)
+                       ls->remount = 0;
+       }
 
        optlist_cleanup_cached(ls, opt->map);
 
@@ -213,8 +225,11 @@ struct libmnt_opt *mnt_optlist_get_opt(struct libmnt_optlist *ls,
        mnt_reset_iter(&itr, MNT_ITER_FORWARD);
 
        while (mnt_optlist_next_opt(ls, &itr, &opt) == 0) {
-               if (!opt->external && opt->map == map
-                   && opt->ent && (unsigned long) opt->ent->id == id)
+               if (opt->external)
+                       continue;
+               if (map && opt->map != map)
+                       continue;
+               if (opt->ent && (unsigned long) opt->ent->id == id)
                        return opt;
        }
 
@@ -233,7 +248,7 @@ struct libmnt_opt *mnt_optlist_get_named(struct libmnt_optlist *ls,
        mnt_reset_iter(&itr, MNT_ITER_FORWARD);
 
        while (mnt_optlist_next_opt(ls, &itr, &opt) == 0) {
-               if (!opt->external)
+               if (opt->external)
                        continue;
                if (map && map != opt->map)
                        continue;
@@ -329,8 +344,12 @@ static struct libmnt_opt *optlist_new_opt(struct libmnt_optlist *ls,
        else
                list_add_tail(&opt->opts, &ls->opts);
 
-       if (map && ent && map == ls->linux_map && ent->id & MS_PROPAGATION)
-               ls->propagation |= ent->id;
+       if (map && ent && map == ls->linux_map) {
+               if (ent->id & MS_PROPAGATION)
+                       ls->propagation |= ent->id;
+               else if (ent->id == MS_REMOUNT)
+                       ls->remount = 1;
+       }
 
        if (ent && map) {
                DBG(OPTLIST, ul_debugobj(ls, " added %s [id=0x%08x map=%p]",
@@ -561,22 +580,27 @@ int mnt_optlist_insert_flags(struct libmnt_optlist *ls, unsigned long flags,
 
 /* like mnt_optstr_get_flags() */
 int mnt_optlist_get_flags(struct libmnt_optlist *ls, unsigned long *flags,
-                         const struct libmnt_optmap *map)
+                         const struct libmnt_optmap *map, unsigned int what)
 {
        struct libmnt_iter itr;
        struct libmnt_opt *opt;
        unsigned long fl = *flags;
 
-       if (!ls || !map)
+       if (!ls || !map || ((what & MNT_OPTLIST_UNKNOWN) && map))
                return -EINVAL;
 
        mnt_reset_iter(&itr, MNT_ITER_FORWARD);
 
        while (mnt_optlist_next_opt(ls, &itr, &opt) == 0) {
-               if (opt->map != map || !opt->ent || !opt->ent->id)
+               if ((what & MNT_OPTLIST_UNKNOWN) && opt->map)
                        continue;
-               if (opt->external)
+               if (map && opt->map != map)
+                       continue;
+               if (!opt->ent || !opt->ent->id)
+                       continue;
+               if (opt->external && !(what & MNT_OPTLIST_EXTERNAL))
                        continue;
+
                if (opt->ent->mask & MNT_INVERT)
                        fl &= ~opt->ent->id;
                else
@@ -589,62 +613,85 @@ int mnt_optlist_get_flags(struct libmnt_optlist *ls, unsigned long *flags,
 }
 
 int mnt_optlist_get_optstr(struct libmnt_optlist *ls, const char **optstr,
-                       const struct libmnt_optmap *map)
+                       const struct libmnt_optmap *map, unsigned int what)
 {
        struct libmnt_iter itr;
        struct libmnt_opt *opt;
        struct ul_buffer buf = UL_INIT_BUFFER;
        size_t idx = 0;
-       char *str = NULL;
+       char *str = NULL, **cache = NULL;
+       int rc = 0;
 
-       if (!ls || !optstr)
+       if (!ls || !optstr || ((what & MNT_OPTLIST_UNKNOWN) && map))
                return -EINVAL;
 
        *optstr = NULL;
 
-       if (map) {
-               idx = optlist_get_mapidx(ls, map);
-               if (idx == (size_t) -1)
-                       return -EINVAL;
-               if (ls->cached_str[idx])
-                       str = ls->cached_str[idx];
-       } else if (ls->cached_all)
-               str = ls->cached_all;
+       switch (what) {
+       case MNT_OPTLIST_DEFAULT:
+               if (map) {
+                       idx = optlist_get_mapidx(ls, map);
+                       if (idx == (size_t) -1)
+                               return -EINVAL;
+                       if (ls->cached_str[idx])
+                               cache = &ls->cached_str[idx];
+               } else
+                       cache = &ls->cached_all;
+               break;
+       case MNT_OPTLIST_UNKNOWN:
+               cache = &ls->cached_unknown;
+               break;
+       default:
+               break;
+       }
 
-       if (str)
+       if (cache && *cache) {
+               str = *cache;
                goto done;
+       }
+
+       /* For generic options string prepend 'rw' if 'ro' not specified */
+       if (!map) {
+               opt = mnt_optlist_get_opt(ls, MS_RDONLY, ls->linux_map);
+               if (!opt
+                   && (rc = mnt_buffer_append_option(&buf, "rw", 2, NULL, 0)))
+                       goto fail;
+       }
 
        mnt_reset_iter(&itr, MNT_ITER_FORWARD);
 
        while (mnt_optlist_next_opt(ls, &itr, &opt) == 0) {
-               int rc;
-
+               if ((what & MNT_OPTLIST_UNKNOWN) && opt->map)
+                       continue;
                if (map && opt->map != map)
                        continue;
                if (!opt->name)
                        continue;
+               if (opt->external && !(what & MNT_OPTLIST_EXTERNAL))
+                       continue;
+
                rc = mnt_buffer_append_option(&buf,
                                        opt->name, strlen(opt->name),
                                        opt->value,
                                        opt->value ? strlen(opt->value) : 0);
-               if (rc) {
-                       ul_buffer_free_data(&buf);
-                       return rc;
-               }
+               if (rc)
+                       goto fail;
+
        }
 
        str = ul_buffer_get_data(&buf, NULL, NULL);
-       if (map)
-               ls->cached_str[idx] = str;
-       else
-               ls->cached_all = str;
 
+       if (cache)
+               *cache = str;
 done:
        if (optstr)
                *optstr = str;
 
        DBG(OPTLIST, ul_debugobj(ls, "return optstr %s", str));
        return 0;
+fail:
+       ul_buffer_free_data(&buf);
+       return rc;
 }
 
 int mnt_optlist_get_propagation(struct libmnt_optlist *ls)
@@ -659,18 +706,71 @@ int mnt_optlist_is_propagation_only(struct libmnt_optlist *ls)
        if (!ls || !ls->propagation || !ls->nmaps)
                return 0;
 
-       if (mnt_optlist_get_flags(ls, &flags, ls->linux_map) != 0)
+       if (mnt_optlist_get_flags(ls, &flags, ls->linux_map, 0) != 0)
                return 0;
 
        rest = flags & ~MS_PROPAGATION;
        return (rest == 0 || rest == MS_SILENT);
 }
 
+int mnt_optlist_is_remount(struct libmnt_optlist *ls)
+{
+       return ls && ls->remount;
+}
+
 int mnt_opt_has_value(struct libmnt_opt *opt)
 {
        return opt && opt->value;
 }
 
+const char *mnt_opt_get_value(struct libmnt_opt *opt)
+{
+       return opt->value;
+}
+
+const char *mnt_opt_get_name(struct libmnt_opt *opt)
+{
+       return opt->name;
+}
+
+int mnt_opt_set_value(struct libmnt_opt *opt, const char *str)
+{
+       return strdup_to_struct_member(opt, value, str);
+}
+
+int mnt_opt_set_u64value(struct libmnt_opt *opt, uint64_t num)
+{
+       char buf[ sizeof(stringify_value(UINT64_MAX)) ];
+
+        snprintf(buf, sizeof(buf), "%"PRIu64, num);
+
+       return mnt_opt_set_value(opt, buf);
+}
+
+int mnt_opt_set_quoted_value(struct libmnt_opt *opt, const char *str)
+{
+       char *value = NULL;
+
+       if (str && *str) {
+               size_t len = strlen(str);
+               char *p;
+
+               assert(len);
+               p = value = malloc(len + 3);
+               if (!value)
+                       return -ENOMEM;
+               *p++ = '"';
+               memcpy(p, str, len);
+               p += len;
+               *p = '"';
+       }
+
+       free(opt->value);
+       opt->value = value;
+
+       return 0;
+}
+
 int mnt_opt_set_external(struct libmnt_opt *opt, int enable)
 {
        if (!opt)
@@ -826,7 +926,7 @@ static int test_get_str(struct libmnt_test *ts, int argc, char *argv[])
        rc = mk_optlist(&ol, argv[1]);
        if (!rc) {
                mnt_optlist_merge_opts(ol);
-               rc = mnt_optlist_get_optstr(ol, &str, get_map(argv[2]));
+               rc = mnt_optlist_get_optstr(ol, &str, get_map(argv[2]), 0);
        }
        if (!rc)
                printf("'%s'\n", str);
@@ -845,7 +945,7 @@ static int test_get_flg(struct libmnt_test *ts, int argc, char *argv[])
                return -EINVAL;
        rc = mk_optlist(&ol, argv[1]);
        if (!rc)
-               rc = mnt_optlist_get_flags(ol, &flags, get_map(argv[2]));
+               rc = mnt_optlist_get_flags(ol, &flags, get_map(argv[2]), 0);
        if (!rc)
                printf("0x%08lx\n", flags);
        mnt_unref_optlist(ol);