chiark / gitweb /
shared: make timezone and locale enumeration and validation generic
[elogind.git] / src / shared / locale-util.c
diff --git a/src/shared/locale-util.c b/src/shared/locale-util.c
new file mode 100644 (file)
index 0000000..8d2c363
--- /dev/null
@@ -0,0 +1,205 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2014 Lennart Poettering
+
+  systemd 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.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/mman.h>
+
+#include "set.h"
+#include "util.h"
+#include "utf8.h"
+#include "strv.h"
+
+#include "locale-util.h"
+
+static int add_locales_from_archive(Set *locales) {
+        /* Stolen from glibc... */
+
+        struct locarhead {
+                uint32_t magic;
+                /* Serial number.  */
+                uint32_t serial;
+                /* Name hash table.  */
+                uint32_t namehash_offset;
+                uint32_t namehash_used;
+                uint32_t namehash_size;
+                /* String table.  */
+                uint32_t string_offset;
+                uint32_t string_used;
+                uint32_t string_size;
+                /* Table with locale records.  */
+                uint32_t locrectab_offset;
+                uint32_t locrectab_used;
+                uint32_t locrectab_size;
+                /* MD5 sum hash table.  */
+                uint32_t sumhash_offset;
+                uint32_t sumhash_used;
+                uint32_t sumhash_size;
+        };
+
+        struct namehashent {
+                /* Hash value of the name.  */
+                uint32_t hashval;
+                /* Offset of the name in the string table.  */
+                uint32_t name_offset;
+                /* Offset of the locale record.  */
+                uint32_t locrec_offset;
+        };
+
+        const struct locarhead *h;
+        const struct namehashent *e;
+        const void *p = MAP_FAILED;
+        _cleanup_close_ int fd = -1;
+        size_t sz = 0;
+        struct stat st;
+        unsigned i;
+        int r;
+
+        fd = open("/usr/lib/locale/locale-archive", O_RDONLY|O_NOCTTY|O_CLOEXEC);
+        if (fd < 0)
+                return errno == ENOENT ? 0 : -errno;
+
+        if (fstat(fd, &st) < 0)
+                return -errno;
+
+        if (!S_ISREG(st.st_mode))
+                return -EBADMSG;
+
+        if (st.st_size < (off_t) sizeof(struct locarhead))
+                return -EBADMSG;
+
+        p = mmap(NULL, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
+        if (p == MAP_FAILED)
+                return -errno;
+
+        h = (const struct locarhead *) p;
+        if (h->magic != 0xde020109 ||
+            h->namehash_offset + h->namehash_size > st.st_size ||
+            h->string_offset + h->string_size > st.st_size ||
+            h->locrectab_offset + h->locrectab_size > st.st_size ||
+            h->sumhash_offset + h->sumhash_size > st.st_size) {
+                r = -EBADMSG;
+                goto finish;
+        }
+
+        e = (const struct namehashent*) ((const uint8_t*) p + h->namehash_offset);
+        for (i = 0; i < h->namehash_size; i++) {
+                char *z;
+
+                if (e[i].locrec_offset == 0)
+                        continue;
+
+                if (!utf8_is_valid((char*) p + e[i].name_offset))
+                        continue;
+
+                z = strdup((char*) p + e[i].name_offset);
+                if (!z) {
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                r = set_consume(locales, z);
+                if (r < 0)
+                        goto finish;
+        }
+
+        r = 0;
+
+ finish:
+        if (p != MAP_FAILED)
+                munmap((void*) p, sz);
+
+        return r;
+}
+
+static int add_locales_from_libdir (Set *locales) {
+        _cleanup_closedir_ DIR *dir = NULL;
+        struct dirent *entry;
+        int r;
+
+        dir = opendir("/usr/lib/locale");
+        if (!dir)
+                return errno == ENOENT ? 0 : -errno;
+
+        FOREACH_DIRENT(entry, dir, return -errno) {
+                char *z;
+
+                if (entry->d_type != DT_DIR)
+                        continue;
+
+                z = strdup(entry->d_name);
+                if (!z)
+                        return -ENOMEM;
+
+                r = set_consume(locales, z);
+                if (r < 0 && r != -EEXIST)
+                        return r;
+        }
+
+        return 0;
+}
+
+int get_locales(char ***ret) {
+        _cleanup_set_free_ Set *locales = NULL;
+        _cleanup_strv_free_ char **l = NULL;
+        int r;
+
+        locales = set_new(string_hash_func, string_compare_func);
+        if (!locales)
+                return -ENOMEM;
+
+        r = add_locales_from_archive(locales);
+        if (r < 0 && r != -ENOENT)
+                return r;
+
+        r = add_locales_from_libdir(locales);
+        if (r < 0)
+                return r;
+
+        l = set_get_strv(locales);
+        if (!l)
+                return -ENOMEM;
+
+        strv_sort(l);
+
+        *ret = l;
+        l = NULL;
+
+        return 0;
+}
+
+bool locale_is_valid(const char *name) {
+
+        if (isempty(name))
+                return false;
+
+        if (strlen(name) >= 128)
+                return false;
+
+        if (!utf8_is_valid(name))
+                return false;
+
+        if (!filename_is_safe(name))
+                return false;
+
+        if (!string_is_safe(name))
+                return false;
+
+        return true;
+}