1 files changed, 66 insertions, 0 deletions
diff --git a/src/shared/web-util.c b/src/shared/web-util.c
new file mode 100644
index 0000000..39a300f
--- /dev/null
+++ b/src/shared/web-util.c
@@ -0,0 +1,66 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <stdbool.h>
+
+#include "string-util.h"
+#include "strv.h"
+#include "utf8.h"
+#include "web-util.h"
+
+bool http_etag_is_valid(const char *etag) {
+        if (isempty(etag))
+                return false;
+
+        if (!endswith(etag, "\""))
+                return false;
+
+        if (!STARTSWITH_SET(etag, "\"", "W/\""))
+                return false;
+
+        return true;
+}
+
+bool http_url_is_valid(const char *url) {
+        const char *p;
+
+        if (isempty(url))
+                return false;
+
+        p = STARTSWITH_SET(url, "http://", "https://");
+        if (!p)
+                return false;
+
+        if (isempty(p))
+                return false;
+
+        return ascii_is_valid(p);
+}
+
+bool file_url_is_valid(const char *url) {
+        const char *p;
+
+        if (isempty(url))
+                return false;
+
+        p = startswith(url, "file:/");
+        if (isempty(p))
+                return false;
+
+        return ascii_is_valid(p);
+}
+
+bool documentation_url_is_valid(const char *url) {
+        const char *p;
+
+        if (isempty(url))
+                return false;
+
+        if (http_url_is_valid(url) || file_url_is_valid(url))
+                return true;
+
+        p = STARTSWITH_SET(url, "info:", "man:");
+        if (isempty(p))
+                return false;
+
+        return ascii_is_valid(p);
+}