[db] Fetch directory id by path; use const for path and virtual_path

src/db.c

@@ -3850,7 +3850,7 @@ db_group_persistentid_byid(int id, int64_t *persistentid)
 
 /* Directories */
 int
-db_directory_id_byvirtualpath(char *virtual_path)
+db_directory_id_byvirtualpath(const char *virtual_path)
 {
 #define Q_TMPL "SELECT d.id FROM directories d WHERE d.virtual_path = '%q';"
   char *query;
@@ -3873,6 +3873,30 @@ db_directory_id_byvirtualpath(char *virtual_path)
 #undef Q_TMPL
 }
 
+int
+db_directory_id_bypath(const char *path)
+{
+#define Q_TMPL "SELECT d.id FROM directories d WHERE d.path = '%q';"
+  char *query;
+  int ret;
+
+  query = sqlite3_mprintf(Q_TMPL, path);
+  if (!query)
+    {
+      DPRINTF(E_LOG, L_DB, "Out of memory for query string\n");
+
+      return 0;
+    }
+
+  ret = db_file_id_byquery(query);
+
+  sqlite3_free(query);
+
+  return ret;
+
+#undef Q_TMPL
+}
+
 int
 db_directory_enum_start(struct directory_enum *de)
 {

src/db.h

@@ -699,7 +699,10 @@ db_group_persistentid_byid(int id, int64_t *persistentid);
 
 /* Directories */
 int
-db_directory_id_byvirtualpath(char *virtual_path);
+db_directory_id_byvirtualpath(const char *virtual_path);
+
+int
+db_directory_id_bypath(const char *path);
 
 int
 db_directory_enum_start(struct directory_enum *de);