1 /* Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2006, 2011 Free Software Foundation, Inc.
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public License
5 * as published by the Free Software Foundation; either version 3 of
6 * the License, or (at your option) any later version.
8 * This library is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * Lesser General Public License for more details.
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
29 #include "libguile/_scm.h"
30 #include "libguile/dynwind.h"
31 #include "libguile/feature.h"
32 #include "libguile/fports.h"
33 #include "libguile/hashtab.h"
34 #include "libguile/ioext.h"
35 #include "libguile/ports.h"
36 #include "libguile/strings.h"
37 #include "libguile/validate.h"
49 SCM_DEFINE (scm_ftell
, "ftell", 1, 0, 0,
51 "Return an integer representing the current position of\n"
52 "@var{fd_port}, measured from the beginning. Equivalent to:\n"
55 "(seek port 0 SEEK_CUR)\n"
57 #define FUNC_NAME s_scm_ftell
59 return scm_seek (fd_port
, SCM_INUM0
, scm_from_int (SEEK_CUR
));
63 SCM_DEFINE (scm_redirect_port
, "redirect-port", 2, 0, 0,
65 "This procedure takes two ports and duplicates the underlying file\n"
66 "descriptor from @var{old} into @var{new}. The\n"
67 "current file descriptor in @var{new} will be closed.\n"
68 "After the redirection the two ports will share a file position\n"
69 "and file status flags.\n\n"
70 "The return value is unspecified.\n\n"
71 "Unexpected behaviour can result if both ports are subsequently used\n"
72 "and the original and/or duplicate ports are buffered.\n\n"
73 "This procedure does not have any side effects on other ports or\n"
75 #define FUNC_NAME s_scm_redirect_port
77 int ans
, oldfd
, newfd
;
80 old
= SCM_COERCE_OUTPORT (old
);
81 new = SCM_COERCE_OUTPORT (new);
83 SCM_VALIDATE_OPFPORT (1, old
);
84 SCM_VALIDATE_OPFPORT (2, new);
85 oldfd
= SCM_FPORT_FDES (old
);
86 fp
= SCM_FSTREAM (new);
90 scm_t_port
*pt
= SCM_PTAB_ENTRY (new);
91 scm_t_port
*old_pt
= SCM_PTAB_ENTRY (old
);
92 scm_t_ptob_descriptor
*ptob
= SCM_PORT_DESCRIPTOR (new);
94 /* must flush to old fdes. */
95 if (pt
->rw_active
== SCM_PORT_WRITE
)
97 else if (pt
->rw_active
== SCM_PORT_READ
)
98 scm_end_input_unlocked (new);
99 ans
= dup2 (oldfd
, newfd
);
102 pt
->rw_random
= old_pt
->rw_random
;
103 /* continue using existing buffers, even if inappropriate. */
105 return SCM_UNSPECIFIED
;
109 SCM_DEFINE (scm_dup_to_fdes
, "dup->fdes", 1, 1, 0,
110 (SCM fd_or_port
, SCM fd
),
111 "Return a new integer file descriptor referring to the open file\n"
112 "designated by @var{fd_or_port}, which must be either an open\n"
113 "file port or a file descriptor.")
114 #define FUNC_NAME s_scm_dup_to_fdes
116 int oldfd
, newfd
, rv
;
118 fd_or_port
= SCM_COERCE_OUTPORT (fd_or_port
);
120 if (scm_is_integer (fd_or_port
))
121 oldfd
= scm_to_int (fd_or_port
);
124 SCM_VALIDATE_OPFPORT (1, fd_or_port
);
125 oldfd
= SCM_FPORT_FDES (fd_or_port
);
133 fd
= scm_from_int (newfd
);
137 newfd
= scm_to_int (fd
);
140 scm_evict_ports (newfd
); /* see scsh manual. */
141 rv
= dup2 (oldfd
, newfd
);
151 SCM_DEFINE (scm_dup2
, "dup2", 2, 0, 0,
152 (SCM oldfd
, SCM newfd
),
153 "A simple wrapper for the @code{dup2} system call.\n"
154 "Copies the file descriptor @var{oldfd} to descriptor\n"
155 "number @var{newfd}, replacing the previous meaning\n"
156 "of @var{newfd}. Both @var{oldfd} and @var{newfd} must\n"
158 "Unlike for dup->fdes or primitive-move->fdes, no attempt\n"
159 "is made to move away ports which are using @var{newfd}.\n"
160 "The return value is unspecified.")
161 #define FUNC_NAME s_scm_dup2
167 c_oldfd
= scm_to_int (oldfd
);
168 c_newfd
= scm_to_int (newfd
);
169 rv
= dup2 (c_oldfd
, c_newfd
);
172 return SCM_UNSPECIFIED
;
176 SCM_DEFINE (scm_fileno
, "fileno", 1, 0, 0,
178 "Return the integer file descriptor underlying @var{port}. Does\n"
179 "not change its revealed count.")
180 #define FUNC_NAME s_scm_fileno
182 port
= SCM_COERCE_OUTPORT (port
);
183 SCM_VALIDATE_OPFPORT (1, port
);
184 return scm_from_int (SCM_FPORT_FDES (port
));
188 /* GJB:FIXME:: why does this not throw
189 an error if the arg is not a port?
190 This proc as is would be better names isattyport?
191 if it is not going to assume that the arg is a port
193 [cmm] I don't see any problem with the above. why should a type
194 predicate assume _anything_ about its argument?
196 SCM_DEFINE (scm_isatty_p
, "isatty?", 1, 0, 0,
198 "Return @code{#t} if @var{port} is using a serial non--file\n"
199 "device, otherwise @code{#f}.")
200 #define FUNC_NAME s_scm_isatty_p
204 port
= SCM_COERCE_OUTPORT (port
);
206 if (!SCM_OPFPORTP (port
))
209 rv
= isatty (SCM_FPORT_FDES (port
));
210 return scm_from_bool(rv
);
216 SCM_DEFINE (scm_fdopen
, "fdopen", 2, 0, 0,
217 (SCM fdes
, SCM modes
),
218 "Return a new port based on the file descriptor @var{fdes}.\n"
219 "Modes are given by the string @var{modes}. The revealed count\n"
220 "of the port is initialized to zero. The modes string is the\n"
221 "same as that accepted by @ref{File Ports, open-file}.")
222 #define FUNC_NAME s_scm_fdopen
224 return scm_i_fdes_to_port (scm_to_int (fdes
),
225 scm_i_mode_bits (modes
), SCM_BOOL_F
);
231 /* Move a port's underlying file descriptor to a given value.
232 * Returns #f if fdes is already the given value.
234 * MOVE->FDES is implemented in Scheme and calls this primitive.
236 SCM_DEFINE (scm_primitive_move_to_fdes
, "primitive-move->fdes", 2, 0, 0,
238 "Moves the underlying file descriptor for @var{port} to the integer\n"
239 "value @var{fd} without changing the revealed count of @var{port}.\n"
240 "Any other ports already using this descriptor will be automatically\n"
241 "shifted to new descriptors and their revealed counts reset to zero.\n"
242 "The return value is @code{#f} if the file descriptor already had the\n"
243 "required value or @code{#t} if it was moved.")
244 #define FUNC_NAME s_scm_primitive_move_to_fdes
251 port
= SCM_COERCE_OUTPORT (port
);
253 SCM_VALIDATE_OPFPORT (1, port
);
254 stream
= SCM_FSTREAM (port
);
255 old_fd
= stream
->fdes
;
256 new_fd
= scm_to_int (fd
);
257 if (old_fd
== new_fd
)
261 scm_evict_ports (new_fd
);
262 rv
= dup2 (old_fd
, new_fd
);
265 stream
->fdes
= new_fd
;
266 SCM_SYSCALL (close (old_fd
));
272 get_matching_port (void *closure
, SCM port
, SCM result
)
274 int fd
= * (int *) closure
;
275 scm_t_port
*entry
= SCM_PTAB_ENTRY (port
);
277 if (SCM_OPFPORTP (port
)
278 && ((scm_t_fport
*) entry
->stream
)->fdes
== fd
)
279 result
= scm_cons (port
, result
);
284 /* Return a list of ports using a given file descriptor. */
285 SCM_DEFINE (scm_fdes_to_ports
, "fdes->ports", 1, 0, 0,
287 "Return a list of existing ports which have @var{fd} as an\n"
288 "underlying file descriptor, without changing their revealed\n"
290 #define FUNC_NAME s_scm_fdes_to_ports
292 SCM result
= SCM_EOL
;
293 int int_fd
= scm_to_int (fd
);
295 result
= scm_c_weak_set_fold (get_matching_port
,
296 (void*) &int_fd
, result
,
297 scm_i_port_weak_set
);
306 scm_add_feature ("i/o-extensions");
308 #include "libguile/ioext.x"