Add tests for x509_csr_parse
diff --git a/include/polarssl/x509_csr.h b/include/polarssl/x509_csr.h
index 4328598..deac88f 100644
--- a/include/polarssl/x509_csr.h
+++ b/include/polarssl/x509_csr.h
@@ -116,8 +116,8 @@
* \param prefix A line prefix
* \param csr The X509 CSR to represent
*
- * \return The amount of data written to the buffer, or -1 in
- * case of an error.
+ * \return The length of the string written (exluding the terminating
+ * null byte), or a negative value in case of an error.
*/
int x509_csr_info( char *buf, size_t size, const char *prefix,
const x509_csr *csr );