+
+_public_ int sd_bus_path_encode_many(char **out, const char *path_template, ...) {
+ _cleanup_strv_free_ char **labels = NULL;
+ char *path, *path_pos, **label_pos;
+ const char *sep, *template_pos;
+ size_t path_length;
+ va_list list;
+ int r;
+
+ assert_return(out, -EINVAL);
+ assert_return(path_template, -EINVAL);
+
+ path_length = strlen(path_template);
+
+ va_start(list, path_template);
+ for (sep = strchr(path_template, '%'); sep; sep = strchr(sep + 1, '%')) {
+ const char *arg;
+ char *label;
+
+ arg = va_arg(list, const char *);
+ if (!arg) {
+ va_end(list);
+ return -EINVAL;
+ }
+
+ label = bus_label_escape(arg);
+ if (!label) {
+ va_end(list);
+ return -ENOMEM;
+ }
+
+ r = strv_consume(&labels, label);
+ if (r < 0) {
+ va_end(list);
+ return r;
+ }
+
+ /* add label length, but account for the format character */
+ path_length += strlen(label) - 1;
+ }
+ va_end(list);
+
+ path = malloc(path_length + 1);
+ if (!path)
+ return -ENOMEM;
+
+ path_pos = path;
+ label_pos = labels;
+
+ for (template_pos = path_template; *template_pos; ) {
+ sep = strchrnul(template_pos, '%');
+ path_pos = mempcpy(path_pos, template_pos, sep - template_pos);
+ if (!*sep)
+ break;
+
+ path_pos = stpcpy(path_pos, *label_pos++);
+ template_pos = sep + 1;
+ }
+
+ *path_pos = 0;
+ *out = path;
+ return 0;
+}
+
+_public_ int sd_bus_path_decode_many(const char *path, const char *path_template, ...) {
+ _cleanup_strv_free_ char **labels = NULL;
+ const char *template_pos, *path_pos;
+ char **label_pos;
+ va_list list;
+ int r;
+
+ /*
+ * This decodes an object-path based on a template argument. The
+ * template consists of a verbatim path, optionally including special
+ * directives:
+ *
+ * - Each occurrence of '%' in the template matches an arbitrary
+ * substring of a label in the given path. At most one such
+ * directive is allowed per label. For each such directive, the
+ * caller must provide an output parameter (char **) via va_arg. If
+ * NULL is passed, the given label is verified, but not returned.
+ * For each matched label, the *decoded* label is stored in the
+ * passed output argument, and the caller is responsible to free
+ * it. Note that the output arguments are only modified if the
+ * actualy path matched the template. Otherwise, they're left
+ * untouched.
+ *
+ * This function returns <0 on error, 0 if the path does not match the
+ * template, 1 if it matched.
+ */
+
+ assert_return(path, -EINVAL);
+ assert_return(path_template, -EINVAL);
+
+ path_pos = path;
+
+ for (template_pos = path_template; *template_pos; ) {
+ const char *sep;
+ size_t length;
+ char *label;
+
+ /* verify everything until the next '%' matches verbatim */
+ sep = strchrnul(template_pos, '%');
+ length = sep - template_pos;
+ if (strncmp(path_pos, template_pos, length))
+ return 0;
+
+ path_pos += length;
+ template_pos += length;
+
+ if (!*template_pos)
+ break;
+
+ /* We found the next '%' character. Everything up until here
+ * matched. We now skip ahead to the end of this label and make
+ * sure it matches the tail of the label in the path. Then we
+ * decode the string in-between and save it for later use. */
+
+ ++template_pos; /* skip over '%' */
+
+ sep = strchrnul(template_pos, '/');
+ length = sep - template_pos; /* length of suffix to match verbatim */
+
+ /* verify the suffixes match */
+ sep = strchrnul(path_pos, '/');
+ if (sep - path_pos < (ssize_t)length ||
+ strncmp(sep - length, template_pos, length))
+ return 0;
+
+ template_pos += length; /* skip over matched label */
+ length = sep - path_pos - length; /* length of sub-label to decode */
+
+ /* store unescaped label for later use */
+ label = bus_label_unescape_n(path_pos, length);
+ if (!label)
+ return -ENOMEM;
+
+ r = strv_consume(&labels, label);
+ if (r < 0)
+ return r;
+
+ path_pos = sep; /* skip decoded label and suffix */
+ }
+
+ /* end of template must match end of path */
+ if (*path_pos)
+ return 0;
+
+ /* copy the labels over to the caller */
+ va_start(list, path_template);
+ for (label_pos = labels; label_pos && *label_pos; ++label_pos) {
+ char **arg;
+
+ arg = va_arg(list, char **);
+ if (arg)
+ *arg = *label_pos;
+ else
+ free(*label_pos);
+ }
+ va_end(list);
+
+ free(labels);
+ labels = NULL;
+ return 1;
+}
~ianmdlvl / elogind.git / commitdiff