Use exact prefix for search_url entries

Instead of matching any entry that starts with the given prefix, make
sure that we are matching the whole prefix until the space. This allows
multiple entries to have common starting substrings.

See: https://lists.mailman3.com/hyperkitty/list/dillo-dev@mailman3.com/thread/N3PO6NNPDYWPT2UVSLWTO5SZTOKIOXAI/

Author: rodarima

ChangeLog

@@ -29,6 +29,7 @@ dillo-3.3.0 [Unreleased]
  - Add "mark_unloaded_images" option to show a border in images not loaded, so
    they are easier to see.
  - Fix segfault on CurveBall TLS test with LibreSSL.
+ - Match complete search prefixes in "search_url" to avoid partial matches.
    Patches: Rodrigo Arias Mallo
 +- Middle click on back or forward button opens page in new tab.
    Patches: Alex

src/uicmd.cc

@@ -754,6 +754,9 @@ static char *UIcmd_find_search_str(const char *str)
          const char *search =
             (const char *)dList_nth_data(prefs.search_urls, p);
          if (search && dStrnAsciiCasecmp(str, search, len) == 0) {
+            /* Are we partially matching another entry? */
+            if (search[len] != ' ')
+               continue;
             prefs.search_url_idx = p;
             url = UIcmd_make_search_str(str + len + 1);
             break;