1 files changed, 87 insertions, 0 deletions
diff --git a/src/shared/device-nodes.c b/src/shared/device-nodes.c
new file mode 100644
index 0000000..d08c40f
--- /dev/null
+++ b/src/shared/device-nodes.c
@@ -0,0 +1,87 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "device-nodes.h"
+#include "path-util.h"
+#include "string-util.h"
+#include "utf8.h"
+
+int allow_listed_char_for_devnode(char c, const char *additional) {
+        return
+                ascii_isdigit(c) ||
+                ascii_isalpha(c) ||
+                strchr("#+-.:=@_", c) ||
+                (additional && strchr(additional, c));
+}
+
+int encode_devnode_name(const char *str, char *str_enc, size_t len) {
+        size_t i, j;
+
+        if (!str || !str_enc)
+                return -EINVAL;
+
+        for (i = 0, j = 0; str[i] != '\0'; i++) {
+                int seqlen;
+
+                seqlen = utf8_encoded_valid_unichar(str + i, SIZE_MAX);
+                if (seqlen > 1) {
+
+                        if (len-j < (size_t) seqlen)
+                                return -EINVAL;
+
+                        memcpy(&str_enc[j], &str[i], seqlen);
+                        j += seqlen;
+                        i += (seqlen-1);
+
+                } else if (str[i] == '\\' || !allow_listed_char_for_devnode(str[i], NULL)) {
+
+                        if (len-j < 4)
+                                return -EINVAL;
+
+                        sprintf(&str_enc[j], "\\x%02x", (unsigned char) str[i]);
+                        j += 4;
+
+                } else {
+                        if (len-j < 1)
+                                return -EINVAL;
+
+                        str_enc[j] = str[i];
+                        j++;
+                }
+        }
+
+        if (len-j < 1)
+                return -EINVAL;
+
+        str_enc[j] = '\0';
+        return 0;
+}
+
+int devnode_same(const char *a, const char *b) {
+        struct stat sa, sb;
+
+        assert(a);
+        assert(b);
+
+        if (!valid_device_node_path(a) || !valid_device_node_path(b))
+                return -EINVAL;
+
+        if (stat(a, &sa) < 0)
+                return -errno;
+        if (stat(b, &sb) < 0)
+                return -errno;
+
+        if (!S_ISBLK(sa.st_mode) && !S_ISCHR(sa.st_mode))
+                return -ENODEV;
+        if (!S_ISBLK(sb.st_mode) && !S_ISCHR(sb.st_mode))
+                return -ENODEV;
+
+        if (((sa.st_mode ^ sb.st_mode) & S_IFMT) != 0) /* both inode same device node type? */
+                return false;
+
+        return sa.st_rdev == sb.st_rdev;
+}