c0d5f8b555
* libguile/vports.c (struct soft_port): New data structure. (scm_make_soft_port): Unpack vector into struct when making soft port. (soft_port_input_waiting, soft_port_close, soft_port_fill_input): (soft_port_write, soft_port_flush): Adapt. Remove an extraneous errno=0 in soft_port_close.
255 lines
7 KiB
C
255 lines
7 KiB
C
/* Copyright (C) 1995,1996,1998,1999,2000,2001, 2002, 2003, 2006, 2009, 2010, 2011, 2013 Free Software Foundation, Inc.
|
||
*
|
||
* This library is free software; you can redistribute it and/or
|
||
* modify it under the terms of the GNU Lesser General Public License
|
||
* as published by the Free Software Foundation; either version 3 of
|
||
* the License, or (at your option) any later version.
|
||
*
|
||
* This library is distributed in the hope that it will be useful, but
|
||
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
* Lesser General Public License for more details.
|
||
*
|
||
* You should have received a copy of the GNU Lesser General Public
|
||
* License along with this library; if not, write to the Free Software
|
||
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
||
* 02110-1301 USA
|
||
*/
|
||
|
||
|
||
|
||
#ifdef HAVE_CONFIG_H
|
||
# include <config.h>
|
||
#endif
|
||
|
||
#include <stdio.h>
|
||
#include <errno.h>
|
||
|
||
#include "libguile/_scm.h"
|
||
#include "libguile/eval.h"
|
||
#include "libguile/chars.h"
|
||
#include "libguile/ports.h"
|
||
#include "libguile/ports-internal.h"
|
||
#include "libguile/fports.h"
|
||
#include "libguile/root.h"
|
||
#include "libguile/strings.h"
|
||
#include "libguile/vectors.h"
|
||
|
||
#include "libguile/validate.h"
|
||
#include "libguile/vports.h"
|
||
|
||
#ifdef HAVE_STRING_H
|
||
#include <string.h>
|
||
#endif
|
||
|
||
|
||
|
||
/* {Ports - soft ports}
|
||
*
|
||
*/
|
||
|
||
|
||
static scm_t_bits scm_tc16_soft_port;
|
||
|
||
struct soft_port {
|
||
SCM write_char;
|
||
SCM write_string;
|
||
SCM flush;
|
||
SCM read_char;
|
||
SCM close;
|
||
SCM input_waiting;
|
||
};
|
||
|
||
|
||
static void
|
||
soft_port_flush (SCM port)
|
||
{
|
||
struct soft_port *stream = (void *) SCM_STREAM (port);
|
||
|
||
if (scm_is_true (stream->flush))
|
||
scm_call_0 (stream->flush);
|
||
}
|
||
|
||
static void
|
||
soft_port_write (SCM port, const void *data, size_t size)
|
||
{
|
||
struct soft_port *stream = (void *) SCM_STREAM (port);
|
||
|
||
/* DATA is assumed to be a locale-encoded C string, which makes it
|
||
hard to reliably pass binary data to a soft port. It can be
|
||
achieved by choosing a Latin-1 locale, though, but the recommended
|
||
approach is to use an R6RS "custom binary output port" instead. */
|
||
scm_call_1 (stream->write_string,
|
||
scm_from_locale_stringn ((char *) data, size));
|
||
}
|
||
|
||
/* calling the flush proc (element 2) is in case old code needs it,
|
||
but perhaps softports could the use port buffer in the same way as
|
||
fports. */
|
||
|
||
/* places a single char in the input buffer. */
|
||
static int
|
||
soft_port_fill_input (SCM port)
|
||
{
|
||
struct soft_port *stream = (void *) SCM_STREAM (port);
|
||
SCM ans;
|
||
scm_t_wchar c;
|
||
scm_t_port_internal *pti;
|
||
|
||
ans = scm_call_0 (stream->read_char);
|
||
if (scm_is_false (ans) || SCM_EOF_OBJECT_P (ans))
|
||
return EOF;
|
||
SCM_ASSERT (SCM_CHARP (ans), ans, SCM_ARG1, "soft_port_fill_input");
|
||
pti = SCM_PORT_GET_INTERNAL (port);
|
||
|
||
c = SCM_CHAR (ans);
|
||
|
||
if (pti->encoding_mode == SCM_PORT_ENCODING_MODE_LATIN1
|
||
|| (pti->encoding_mode == SCM_PORT_ENCODING_MODE_UTF8 && c < 0xff))
|
||
{
|
||
scm_t_port *pt = SCM_PTAB_ENTRY (port);
|
||
|
||
*pt->read_buf = c;
|
||
pt->read_pos = pt->read_buf;
|
||
pt->read_end = pt->read_buf + 1;
|
||
}
|
||
else
|
||
{
|
||
long line = SCM_LINUM (port);
|
||
int column = SCM_COL (port);
|
||
|
||
scm_ungetc_unlocked (c, port);
|
||
|
||
SCM_LINUM (port) = line;
|
||
SCM_COL (port) = column;
|
||
}
|
||
|
||
return c;
|
||
}
|
||
|
||
|
||
static int
|
||
soft_port_close (SCM port)
|
||
{
|
||
struct soft_port *stream = (void *) SCM_STREAM (port);
|
||
if (scm_is_false (stream->close))
|
||
return 0;
|
||
return scm_is_false (scm_call_0 (stream->close)) ? EOF : 0;
|
||
}
|
||
|
||
|
||
static int
|
||
soft_port_input_waiting (SCM port)
|
||
{
|
||
struct soft_port *stream = (void *) SCM_STREAM (port);
|
||
if (scm_is_true (stream->input_waiting))
|
||
return scm_to_int (scm_call_0 (stream->input_waiting));
|
||
/* Default is such that char-ready? for soft ports returns #t, as it
|
||
did before this extension was implemented. */
|
||
return 1;
|
||
}
|
||
|
||
|
||
|
||
SCM_DEFINE (scm_make_soft_port, "make-soft-port", 2, 0, 0,
|
||
(SCM pv, SCM modes),
|
||
"Return a port capable of receiving or delivering characters as\n"
|
||
"specified by the @var{modes} string (@pxref{File Ports,\n"
|
||
"open-file}). @var{pv} must be a vector of length 5 or 6. Its\n"
|
||
"components are as follows:\n"
|
||
"\n"
|
||
"@enumerate 0\n"
|
||
"@item\n"
|
||
"procedure accepting one character for output\n"
|
||
"@item\n"
|
||
"procedure accepting a string for output\n"
|
||
"@item\n"
|
||
"thunk for flushing output\n"
|
||
"@item\n"
|
||
"thunk for getting one character\n"
|
||
"@item\n"
|
||
"thunk for closing port (not by garbage collection)\n"
|
||
"@item\n"
|
||
"(if present and not @code{#f}) thunk for computing the number of\n"
|
||
"characters that can be read from the port without blocking.\n"
|
||
"@end enumerate\n"
|
||
"\n"
|
||
"For an output-only port only elements 0, 1, 2, and 4 need be\n"
|
||
"procedures. For an input-only port only elements 3 and 4 need\n"
|
||
"be procedures. Thunks 2 and 4 can instead be @code{#f} if\n"
|
||
"there is no useful operation for them to perform.\n"
|
||
"\n"
|
||
"If thunk 3 returns @code{#f} or an @code{eof-object}\n"
|
||
"(@pxref{Input, eof-object?, ,r5rs, The Revised^5 Report on\n"
|
||
"Scheme}) it indicates that the port has reached end-of-file.\n"
|
||
"For example:\n"
|
||
"\n"
|
||
"@lisp\n"
|
||
"(define stdout (current-output-port))\n"
|
||
"(define p (make-soft-port\n"
|
||
" (vector\n"
|
||
" (lambda (c) (write c stdout))\n"
|
||
" (lambda (s) (display s stdout))\n"
|
||
" (lambda () (display \".\" stdout))\n"
|
||
" (lambda () (char-upcase (read-char)))\n"
|
||
" (lambda () (display \"@@\" stdout)))\n"
|
||
" \"rw\"))\n"
|
||
"\n"
|
||
"(write p p) @result{} #<input-output: soft 8081e20>\n"
|
||
"@end lisp")
|
||
#define FUNC_NAME s_scm_make_soft_port
|
||
{
|
||
int vlen;
|
||
SCM z;
|
||
struct soft_port *stream;
|
||
|
||
SCM_VALIDATE_VECTOR (1, pv);
|
||
vlen = SCM_SIMPLE_VECTOR_LENGTH (pv);
|
||
SCM_ASSERT ((vlen == 5) || (vlen == 6), pv, 1, FUNC_NAME);
|
||
SCM_VALIDATE_STRING (2, modes);
|
||
|
||
stream = scm_gc_typed_calloc (struct soft_port);
|
||
stream->write_char = SCM_SIMPLE_VECTOR_REF (pv, 0);
|
||
stream->write_string = SCM_SIMPLE_VECTOR_REF (pv, 1);
|
||
stream->flush = SCM_SIMPLE_VECTOR_REF (pv, 2);
|
||
stream->read_char = SCM_SIMPLE_VECTOR_REF (pv, 3);
|
||
stream->close = SCM_SIMPLE_VECTOR_REF (pv, 4);
|
||
stream->input_waiting =
|
||
vlen == 6 ? SCM_SIMPLE_VECTOR_REF (pv, 5) : SCM_BOOL_F;
|
||
|
||
z = scm_c_make_port (scm_tc16_soft_port, scm_i_mode_bits (modes),
|
||
(scm_t_bits) stream);
|
||
scm_port_non_buffer (SCM_PTAB_ENTRY (z));
|
||
|
||
return z;
|
||
}
|
||
#undef FUNC_NAME
|
||
|
||
|
||
static scm_t_bits
|
||
scm_make_sfptob ()
|
||
{
|
||
scm_t_bits tc = scm_make_port_type ("soft", soft_port_fill_input,
|
||
soft_port_write);
|
||
|
||
scm_set_port_flush (tc, soft_port_flush);
|
||
scm_set_port_close (tc, soft_port_close);
|
||
scm_set_port_needs_close_on_gc (tc, 1);
|
||
scm_set_port_input_waiting (tc, soft_port_input_waiting);
|
||
|
||
return tc;
|
||
}
|
||
|
||
void
|
||
scm_init_vports ()
|
||
{
|
||
scm_tc16_soft_port = scm_make_sfptob ();
|
||
|
||
#include "libguile/vports.x"
|
||
}
|
||
|
||
/*
|
||
Local Variables:
|
||
c-file-style: "gnu"
|
||
End:
|
||
*/
|