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Diffstat (limited to 'src/libsystemd/sd-id128/id128-util.c')
-rw-r--r--src/libsystemd/sd-id128/id128-util.c194
1 files changed, 194 insertions, 0 deletions
diff --git a/src/libsystemd/sd-id128/id128-util.c b/src/libsystemd/sd-id128/id128-util.c
new file mode 100644
index 0000000000..c3f527d657
--- /dev/null
+++ b/src/libsystemd/sd-id128/id128-util.c
@@ -0,0 +1,194 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2016 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 <fcntl.h>
+#include <unistd.h>
+
+#include "fd-util.h"
+#include "hexdecoct.h"
+#include "id128-util.h"
+#include "io-util.h"
+#include "stdio-util.h"
+
+char *id128_to_uuid_string(sd_id128_t id, char s[37]) {
+ unsigned n, k = 0;
+
+ assert(s);
+
+ /* Similar to sd_id128_to_string() but formats the result as UUID instead of plain hex chars */
+
+ for (n = 0; n < 16; n++) {
+
+ if (IN_SET(n, 4, 6, 8, 10))
+ s[k++] = '-';
+
+ s[k++] = hexchar(id.bytes[n] >> 4);
+ s[k++] = hexchar(id.bytes[n] & 0xF);
+ }
+
+ assert(k == 36);
+
+ s[k] = 0;
+
+ return s;
+}
+
+bool id128_is_valid(const char *s) {
+ size_t i, l;
+
+ assert(s);
+
+ l = strlen(s);
+ if (l == 32) {
+
+ /* Plain formatted 128bit hex string */
+
+ for (i = 0; i < l; i++) {
+ char c = s[i];
+
+ if (!(c >= '0' && c <= '9') &&
+ !(c >= 'a' && c <= 'z') &&
+ !(c >= 'A' && c <= 'Z'))
+ return false;
+ }
+
+ } else if (l == 36) {
+
+ /* Formatted UUID */
+
+ for (i = 0; i < l; i++) {
+ char c = s[i];
+
+ if ((i == 8 || i == 13 || i == 18 || i == 23)) {
+ if (c != '-')
+ return false;
+ } else {
+ if (!(c >= '0' && c <= '9') &&
+ !(c >= 'a' && c <= 'z') &&
+ !(c >= 'A' && c <= 'Z'))
+ return false;
+ }
+ }
+
+ } else
+ return false;
+
+ return true;
+}
+
+int id128_read_fd(int fd, Id128Format f, sd_id128_t *ret) {
+ char buffer[36 + 2];
+ ssize_t l;
+
+ assert(fd >= 0);
+ assert(f < _ID128_FORMAT_MAX);
+
+ /* Reads an 128bit ID from a file, which may either be in plain format (32 hex digits), or in UUID format, both
+ * optionally followed by a newline and nothing else. ID files should really be newline terminated, but if they
+ * aren't that's OK too, following the rule of "Be conservative in what you send, be liberal in what you
+ * accept". */
+
+ l = loop_read(fd, buffer, sizeof(buffer), false); /* we expect a short read of either 32/33 or 36/37 chars */
+ if (l < 0)
+ return (int) l;
+ if (l == 0) /* empty? */
+ return -ENOMEDIUM;
+
+ switch (l) {
+
+ case 33: /* plain UUID with trailing newline */
+ if (buffer[32] != '\n')
+ return -EINVAL;
+
+ /* fall through */
+ case 32: /* plain UUID without trailing newline */
+ if (f == ID128_UUID)
+ return -EINVAL;
+
+ buffer[32] = 0;
+ break;
+
+ case 37: /* RFC UUID with trailing newline */
+ if (buffer[36] != '\n')
+ return -EINVAL;
+
+ /* fall through */
+ case 36: /* RFC UUID without trailing newline */
+ if (f == ID128_PLAIN)
+ return -EINVAL;
+
+ buffer[36] = 0;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return sd_id128_from_string(buffer, ret);
+}
+
+int id128_read(const char *p, Id128Format f, sd_id128_t *ret) {
+ _cleanup_close_ int fd = -1;
+
+ fd = open(p, O_RDONLY|O_CLOEXEC|O_NOCTTY);
+ if (fd < 0)
+ return -errno;
+
+ return id128_read_fd(fd, f, ret);
+}
+
+int id128_write_fd(int fd, Id128Format f, sd_id128_t id, bool do_sync) {
+ char buffer[36 + 2];
+ size_t sz;
+ int r;
+
+ assert(fd >= 0);
+ assert(f < _ID128_FORMAT_MAX);
+
+ if (f != ID128_UUID) {
+ sd_id128_to_string(id, buffer);
+ buffer[32] = '\n';
+ sz = 33;
+ } else {
+ id128_to_uuid_string(id, buffer);
+ buffer[36] = '\n';
+ sz = 37;
+ }
+
+ r = loop_write(fd, buffer, sz, false);
+ if (r < 0)
+ return r;
+
+ if (do_sync) {
+ if (fsync(fd) < 0)
+ return -errno;
+ }
+
+ return r;
+}
+
+int id128_write(const char *p, Id128Format f, sd_id128_t id, bool do_sync) {
+ _cleanup_close_ int fd = -1;
+
+ fd = open(p, O_WRONLY|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444);
+ if (fd < 0)
+ return -errno;
+
+ return id128_write_fd(fd, f, id, do_sync);
+}