Add convenience macros for dynstr_prepend

include/dynstr.h

@@ -61,6 +61,39 @@
 #define dynstr_append_or_ret_nonzero(...) \
    do {if (dynstr_append(__VA_ARGS__) != DYNSTR_OK) return 1;} while (0)
 
+/**
+ * Convenience macro that calls dynstr_prepend and returns NULL if failed.
+ */
+#define dynstr_prepend_or_ret_null(...) \
+   do {if (dynstr_prepend(__VA_ARGS__) != DYNSTR_OK) return NULL;} while (0)
+
+/**
+ * Convenience macro that calls dynstr_prepend and returns false if failed.
+ */
+#define dynstr_prepend_or_ret_false(...) \
+   do {if (dynstr_prepend(__VA_ARGS__) != DYNSTR_OK) return false;} while (0)
+
+/**
+ * Convenience macro that calls dynstr_prepend and returns its error code if failed.
+ */
+#define dynstr_prepend_or_ret(...) \
+   { \
+      const enum dynstr_err err = dynstr_prepend(__VA_ARGS__);  \
+      if (err != DYNSTR_OK) return err; \
+   }
+
+/**
+ * Convenience macro that calls dynstr_prepend and returns zero if failed.
+ */
+#define dynstr_prepend_or_ret_zero(...) \
+   do {if (dynstr_prepend(__VA_ARGS__) != DYNSTR_OK) return 0;} while (0)
+
+/**
+ * Convenience macro that calls dynstr_prepend and returns one if failed.
+ */
+#define dynstr_prepend_or_ret_nonzero(...) \
+   do {if (dynstr_prepend(__VA_ARGS__) != DYNSTR_OK) return 1;} while (0)
+
 /**
  * Dynamic string type used for this library.
  * @note If needed, members can be safely read but should not be modified