Port refactors to help Scheme peek-char

* libguile/ports.h (scm_sys_port_encoding, scm_sys_set_port_encoding):
  New functions, to expose port encodings as symbols directly to (ice-9
  ports).
  (scm_port_maybe_consume_initial_byte_order_mark): New function.
* libguile/ports.c (scm_port_encoding): Dispatch to %port-encoding.
  (scm_set_port_encoding_x): Dispatch to %set-port-encoding!.
  (port_maybe_consume_initial_byte_order_mark): New helper, factored out
  of peek_codepoint.
  (scm_port_maybe_consume_initial_byte_order_mark, peek_codepoint): Call
  port_maybe_consume_initial_byte_order_mark.
* module/ice-9/ports.scm (port-encoding): Implement in Scheme.

1 files changed, 3 insertions, 0 deletions

diff --git a/libguile/ports.h b/libguile/ports.h
index 1572e40e7..cec60212c 100644
--- a/libguile/ports.h
+++ b/libguile/ports.h
@@ -285,12 +285,15 @@ SCM_INTERNAL void scm_i_set_default_port_encoding (const char *encoding);
 SCM_INTERNAL SCM scm_i_default_port_conversion_strategy (void);
 SCM_INTERNAL void scm_i_set_default_port_conversion_strategy (SCM strategy);
 SCM_INTERNAL void scm_i_set_port_encoding_x (SCM port, const char *str);
+SCM_INTERNAL SCM scm_sys_port_encoding (SCM port);
+SCM_INTERNAL SCM scm_sys_set_port_encoding_x (SCM port, SCM encoding);
 SCM_API SCM scm_port_encoding (SCM port);
 SCM_API SCM scm_set_port_encoding_x (SCM port, SCM encoding);
 SCM_API SCM scm_port_conversion_strategy (SCM port);
 SCM_API SCM scm_set_port_conversion_strategy_x (SCM port, SCM behavior);
 
 /* Input.  */
+SCM_INTERNAL SCM scm_port_maybe_consume_initial_byte_order_mark (SCM, SCM, SCM);
 SCM_API int scm_get_byte_or_eof (SCM port);
 SCM_API int scm_peek_byte_or_eof (SCM port);
 SCM_API size_t scm_c_read (SCM port, void *buffer, size_t size);