1 /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2003, 2004, 2006, 2007, 2008 Free Software Foundation, Inc.
2 *
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public
5 * License as published by the Free Software Foundation; either
6 * version 2.1 of the License, or (at your option) any later version.
7 *
8 * This library is distributed in the hope that it will be useful,
9 * but 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.
12 *
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 02110-1301 USA
16 */
17
18
19
20 /* Headers. */
21
22 #define _LARGEFILE64_SOURCE /* ask for stat64 etc */
23
24 #ifdef HAVE_CONFIG_H
25 # include <config.h>
26 #endif
27
28 #include <stdio.h>
29 #include <errno.h>
30 #include <fcntl.h> /* for chsize on mingw */
31 #include <assert.h>
32
33 #include "libguile/_scm.h"
34 #include "libguile/async.h"
35 #include "libguile/eval.h"
36 #include "libguile/fports.h" /* direct access for seek and truncate */
37 #include "libguile/objects.h"
38 #include "libguile/goops.h"
39 #include "libguile/smob.h"
40 #include "libguile/chars.h"
41 #include "libguile/dynwind.h"
42
43 #include "libguile/keywords.h"
44 #include "libguile/root.h"
45 #include "libguile/strings.h"
46 #include "libguile/mallocs.h"
47 #include "libguile/validate.h"
48 #include "libguile/ports.h"
49 #include "libguile/vectors.h"
50 #include "libguile/fluids.h"
51
52 #ifdef HAVE_STRING_H
53 #include <string.h>
54 #endif
55
56 #ifdef HAVE_MALLOC_H
57 #include <stdlib.h>
58 #endif
59
60 #ifdef HAVE_IO_H
61 #include <io.h>
62 #endif
63
64 #ifdef HAVE_UNISTD_H
65 #include <unistd.h>
66 #endif
67
68 #ifdef HAVE_SYS_IOCTL_H
69 #include <sys/ioctl.h>
70 #endif
71
72 /* Mingw (version 3.4.5, circa 2006) has ftruncate as an alias for chsize
73 already, but have this code here in case that wasn't so in past versions,
74 or perhaps to help other minimal DOS environments.
75
76 gnulib ftruncate.c has code using fcntl F_CHSIZE and F_FREESP, which
77 might be possibilities if we've got other systems without ftruncate. */
78
79 #if HAVE_CHSIZE && ! HAVE_FTRUNCATE
80 #define ftruncate(fd, size) chsize (fd, size)
81 #undef HAVE_FTRUNCATE
82 #define HAVE_FTRUNCATE 1
83 #endif
84
85
86 /* The port kind table --- a dynamically resized array of port types. */
87
88
89 /* scm_ptobs scm_numptob
90 * implement a dynamicly resized array of ptob records.
91 * Indexes into this table are used when generating type
92 * tags for smobjects (if you know a tag you can get an index and conversely).
93 */
94 scm_t_ptob_descriptor *scm_ptobs;
95 long scm_numptob;
96
97 /* GC marker for a port with stream of SCM type. */
98 SCM
scm_markstream(SCM ptr)99 scm_markstream (SCM ptr)
100 {
101 int openp;
102 openp = SCM_CELL_WORD_0 (ptr) & SCM_OPN;
103 if (openp)
104 return SCM_PACK (SCM_STREAM (ptr));
105 else
106 return SCM_BOOL_F;
107 }
108
109 /*
110 * We choose to use an interface similar to the smob interface with
111 * fill_input and write as standard fields, passed to the port
112 * type constructor, and optional fields set by setters.
113 */
114
115 static void
flush_port_default(SCM port SCM_UNUSED)116 flush_port_default (SCM port SCM_UNUSED)
117 {
118 }
119
120 static void
end_input_default(SCM port SCM_UNUSED,int offset SCM_UNUSED)121 end_input_default (SCM port SCM_UNUSED, int offset SCM_UNUSED)
122 {
123 }
124
125 static size_t
scm_port_free0(SCM port)126 scm_port_free0 (SCM port)
127 {
128 return 0;
129 }
130
131 scm_t_bits
scm_make_port_type(char * name,int (* fill_input)(SCM port),void (* write)(SCM port,const void * data,size_t size))132 scm_make_port_type (char *name,
133 int (*fill_input) (SCM port),
134 void (*write) (SCM port, const void *data, size_t size))
135 {
136 char *tmp;
137 if (255 <= scm_numptob)
138 goto ptoberr;
139 SCM_CRITICAL_SECTION_START;
140 SCM_SYSCALL (tmp = (char *) realloc ((char *) scm_ptobs,
141 (1 + scm_numptob)
142 * sizeof (scm_t_ptob_descriptor)));
143 if (tmp)
144 {
145 scm_ptobs = (scm_t_ptob_descriptor *) tmp;
146
147 scm_ptobs[scm_numptob].name = name;
148 scm_ptobs[scm_numptob].mark = 0;
149 scm_ptobs[scm_numptob].free = scm_port_free0;
150 scm_ptobs[scm_numptob].print = scm_port_print;
151 scm_ptobs[scm_numptob].equalp = 0;
152 scm_ptobs[scm_numptob].close = 0;
153
154 scm_ptobs[scm_numptob].write = write;
155 scm_ptobs[scm_numptob].flush = flush_port_default;
156
157 scm_ptobs[scm_numptob].end_input = end_input_default;
158 scm_ptobs[scm_numptob].fill_input = fill_input;
159 scm_ptobs[scm_numptob].input_waiting = 0;
160
161 scm_ptobs[scm_numptob].seek = 0;
162 scm_ptobs[scm_numptob].truncate = 0;
163
164 scm_numptob++;
165 }
166 SCM_CRITICAL_SECTION_END;
167 if (!tmp)
168 {
169 ptoberr:
170 scm_memory_error ("scm_make_port_type");
171 }
172 /* Make a class object if Goops is present */
173 if (scm_port_class)
174 scm_make_port_classes (scm_numptob - 1, SCM_PTOBNAME (scm_numptob - 1));
175 return scm_tc7_port + (scm_numptob - 1) * 256;
176 }
177
178 void
scm_set_port_mark(scm_t_bits tc,SCM (* mark)(SCM))179 scm_set_port_mark (scm_t_bits tc, SCM (*mark) (SCM))
180 {
181 scm_ptobs[SCM_TC2PTOBNUM (tc)].mark = mark;
182 }
183
184 void
scm_set_port_free(scm_t_bits tc,size_t (* free)(SCM))185 scm_set_port_free (scm_t_bits tc, size_t (*free) (SCM))
186 {
187 scm_ptobs[SCM_TC2PTOBNUM (tc)].free = free;
188 }
189
190 void
scm_set_port_print(scm_t_bits tc,int (* print)(SCM exp,SCM port,scm_print_state * pstate))191 scm_set_port_print (scm_t_bits tc, int (*print) (SCM exp, SCM port,
192 scm_print_state *pstate))
193 {
194 scm_ptobs[SCM_TC2PTOBNUM (tc)].print = print;
195 }
196
197 void
scm_set_port_equalp(scm_t_bits tc,SCM (* equalp)(SCM,SCM))198 scm_set_port_equalp (scm_t_bits tc, SCM (*equalp) (SCM, SCM))
199 {
200 scm_ptobs[SCM_TC2PTOBNUM (tc)].equalp = equalp;
201 }
202
203 void
scm_set_port_flush(scm_t_bits tc,void (* flush)(SCM port))204 scm_set_port_flush (scm_t_bits tc, void (*flush) (SCM port))
205 {
206 scm_ptobs[SCM_TC2PTOBNUM (tc)].flush = flush;
207 }
208
209 void
scm_set_port_end_input(scm_t_bits tc,void (* end_input)(SCM port,int offset))210 scm_set_port_end_input (scm_t_bits tc, void (*end_input) (SCM port, int offset))
211 {
212 scm_ptobs[SCM_TC2PTOBNUM (tc)].end_input = end_input;
213 }
214
215 void
scm_set_port_close(scm_t_bits tc,int (* close)(SCM))216 scm_set_port_close (scm_t_bits tc, int (*close) (SCM))
217 {
218 scm_ptobs[SCM_TC2PTOBNUM (tc)].close = close;
219 }
220
221 void
scm_set_port_seek(scm_t_bits tc,off_t (* seek)(SCM port,off_t OFFSET,int WHENCE))222 scm_set_port_seek (scm_t_bits tc, off_t (*seek) (SCM port,
223 off_t OFFSET,
224 int WHENCE))
225 {
226 scm_ptobs[SCM_TC2PTOBNUM (tc)].seek = seek;
227 }
228
229 void
scm_set_port_truncate(scm_t_bits tc,void (* truncate)(SCM port,off_t length))230 scm_set_port_truncate (scm_t_bits tc, void (*truncate) (SCM port, off_t length))
231 {
232 scm_ptobs[SCM_TC2PTOBNUM (tc)].truncate = truncate;
233 }
234
235 void
scm_set_port_input_waiting(scm_t_bits tc,int (* input_waiting)(SCM))236 scm_set_port_input_waiting (scm_t_bits tc, int (*input_waiting) (SCM))
237 {
238 scm_ptobs[SCM_TC2PTOBNUM (tc)].input_waiting = input_waiting;
239 }
240
241
242
243 SCM_DEFINE (scm_char_ready_p, "char-ready?", 0, 1, 0,
244 (SCM port),
245 "Return @code{#t} if a character is ready on input @var{port}\n"
246 "and return @code{#f} otherwise. If @code{char-ready?} returns\n"
247 "@code{#t} then the next @code{read-char} operation on\n"
248 "@var{port} is guaranteed not to hang. If @var{port} is a file\n"
249 "port at end of file then @code{char-ready?} returns @code{#t}.\n"
250 "\n"
251 "@code{char-ready?} exists to make it possible for a\n"
252 "program to accept characters from interactive ports without\n"
253 "getting stuck waiting for input. Any input editors associated\n"
254 "with such ports must make sure that characters whose existence\n"
255 "has been asserted by @code{char-ready?} cannot be rubbed out.\n"
256 "If @code{char-ready?} were to return @code{#f} at end of file,\n"
257 "a port at end of file would be indistinguishable from an\n"
258 "interactive port that has no ready characters.")
259 #define FUNC_NAME s_scm_char_ready_p
260 {
261 scm_t_port *pt;
262
263 if (SCM_UNBNDP (port))
264 port = scm_current_input_port ();
265 else
266 SCM_VALIDATE_OPINPORT (1, port);
267
268 pt = SCM_PTAB_ENTRY (port);
269
270 /* if the current read buffer is filled, or the
271 last pushed-back char has been read and the saved buffer is
272 filled, result is true. */
273 if (pt->read_pos < pt->read_end
274 || (pt->read_buf == pt->putback_buf
275 && pt->saved_read_pos < pt->saved_read_end))
276 return SCM_BOOL_T;
277 else
278 {
279 scm_t_ptob_descriptor *ptob = &scm_ptobs[SCM_PTOBNUM (port)];
280
281 if (ptob->input_waiting)
282 return scm_from_bool(ptob->input_waiting (port));
283 else
284 return SCM_BOOL_T;
285 }
286 }
287 #undef FUNC_NAME
288
289 /* move up to read_len chars from port's putback and/or read buffers
290 into memory starting at dest. returns the number of chars moved. */
scm_take_from_input_buffers(SCM port,char * dest,size_t read_len)291 size_t scm_take_from_input_buffers (SCM port, char *dest, size_t read_len)
292 {
293 scm_t_port *pt = SCM_PTAB_ENTRY (port);
294 size_t chars_read = 0;
295 size_t from_buf = min (pt->read_end - pt->read_pos, read_len);
296
297 if (from_buf > 0)
298 {
299 memcpy (dest, pt->read_pos, from_buf);
300 pt->read_pos += from_buf;
301 chars_read += from_buf;
302 read_len -= from_buf;
303 dest += from_buf;
304 }
305
306 /* if putback was active, try the real input buffer too. */
307 if (pt->read_buf == pt->putback_buf)
308 {
309 from_buf = min (pt->saved_read_end - pt->saved_read_pos, read_len);
310 if (from_buf > 0)
311 {
312 memcpy (dest, pt->saved_read_pos, from_buf);
313 pt->saved_read_pos += from_buf;
314 chars_read += from_buf;
315 }
316 }
317 return chars_read;
318 }
319
320 /* Clear a port's read buffers, returning the contents. */
321 SCM_DEFINE (scm_drain_input, "drain-input", 1, 0, 0,
322 (SCM port),
323 "This procedure clears a port's input buffers, similar\n"
324 "to the way that force-output clears the output buffer. The\n"
325 "contents of the buffers are returned as a single string, e.g.,\n"
326 "\n"
327 "@lisp\n"
328 "(define p (open-input-file ...))\n"
329 "(drain-input p) => empty string, nothing buffered yet.\n"
330 "(unread-char (read-char p) p)\n"
331 "(drain-input p) => initial chars from p, up to the buffer size.\n"
332 "@end lisp\n\n"
333 "Draining the buffers may be useful for cleanly finishing\n"
334 "buffered I/O so that the file descriptor can be used directly\n"
335 "for further input.")
336 #define FUNC_NAME s_scm_drain_input
337 {
338 SCM result;
339 char *data;
340 scm_t_port *pt;
341 long count;
342
343 SCM_VALIDATE_OPINPORT (1, port);
344 pt = SCM_PTAB_ENTRY (port);
345
346 count = pt->read_end - pt->read_pos;
347 if (pt->read_buf == pt->putback_buf)
348 count += pt->saved_read_end - pt->saved_read_pos;
349
350 result = scm_i_make_string (count, &data);
351 scm_take_from_input_buffers (port, data, count);
352 return result;
353 }
354 #undef FUNC_NAME
355
356
357 /* Standard ports --- current input, output, error, and more(!). */
358
359 static SCM cur_inport_fluid;
360 static SCM cur_outport_fluid;
361 static SCM cur_errport_fluid;
362 static SCM cur_loadport_fluid;
363
364 SCM_DEFINE (scm_current_input_port, "current-input-port", 0, 0, 0,
365 (),
366 "Return the current input port. This is the default port used\n"
367 "by many input procedures. Initially, @code{current-input-port}\n"
368 "returns the @dfn{standard input} in Unix and C terminology.")
369 #define FUNC_NAME s_scm_current_input_port
370 {
371 return scm_fluid_ref (cur_inport_fluid);
372 }
373 #undef FUNC_NAME
374
375 SCM_DEFINE (scm_current_output_port, "current-output-port", 0, 0, 0,
376 (),
377 "Return the current output port. This is the default port used\n"
378 "by many output procedures. Initially,\n"
379 "@code{current-output-port} returns the @dfn{standard output} in\n"
380 "Unix and C terminology.")
381 #define FUNC_NAME s_scm_current_output_port
382 {
383 return scm_fluid_ref (cur_outport_fluid);
384 }
385 #undef FUNC_NAME
386
387 SCM_DEFINE (scm_current_error_port, "current-error-port", 0, 0, 0,
388 (),
389 "Return the port to which errors and warnings should be sent (the\n"
390 "@dfn{standard error} in Unix and C terminology).")
391 #define FUNC_NAME s_scm_current_error_port
392 {
393 return scm_fluid_ref (cur_errport_fluid);
394 }
395 #undef FUNC_NAME
396
397 SCM_DEFINE (scm_current_load_port, "current-load-port", 0, 0, 0,
398 (),
399 "Return the current-load-port.\n"
400 "The load port is used internally by @code{primitive-load}.")
401 #define FUNC_NAME s_scm_current_load_port
402 {
403 return scm_fluid_ref (cur_loadport_fluid);
404 }
405 #undef FUNC_NAME
406
407 SCM_DEFINE (scm_set_current_input_port, "set-current-input-port", 1, 0, 0,
408 (SCM port),
409 "@deffnx {Scheme Procedure} set-current-output-port port\n"
410 "@deffnx {Scheme Procedure} set-current-error-port port\n"
411 "Change the ports returned by @code{current-input-port},\n"
412 "@code{current-output-port} and @code{current-error-port}, respectively,\n"
413 "so that they use the supplied @var{port} for input or output.")
414 #define FUNC_NAME s_scm_set_current_input_port
415 {
416 SCM oinp = scm_fluid_ref (cur_inport_fluid);
417 SCM_VALIDATE_OPINPORT (1, port);
418 scm_fluid_set_x (cur_inport_fluid, port);
419 return oinp;
420 }
421 #undef FUNC_NAME
422
423
424 SCM_DEFINE (scm_set_current_output_port, "set-current-output-port", 1, 0, 0,
425 (SCM port),
426 "Set the current default output port to @var{port}.")
427 #define FUNC_NAME s_scm_set_current_output_port
428 {
429 SCM ooutp = scm_fluid_ref (cur_outport_fluid);
430 port = SCM_COERCE_OUTPORT (port);
431 SCM_VALIDATE_OPOUTPORT (1, port);
432 scm_fluid_set_x (cur_outport_fluid, port);
433 return ooutp;
434 }
435 #undef FUNC_NAME
436
437
438 SCM_DEFINE (scm_set_current_error_port, "set-current-error-port", 1, 0, 0,
439 (SCM port),
440 "Set the current default error port to @var{port}.")
441 #define FUNC_NAME s_scm_set_current_error_port
442 {
443 SCM oerrp = scm_fluid_ref (cur_errport_fluid);
444 port = SCM_COERCE_OUTPORT (port);
445 SCM_VALIDATE_OPOUTPORT (1, port);
446 scm_fluid_set_x (cur_errport_fluid, port);
447 return oerrp;
448 }
449 #undef FUNC_NAME
450
451 void
scm_dynwind_current_input_port(SCM port)452 scm_dynwind_current_input_port (SCM port)
453 #define FUNC_NAME NULL
454 {
455 SCM_VALIDATE_OPINPORT (1, port);
456 scm_dynwind_fluid (cur_inport_fluid, port);
457 }
458 #undef FUNC_NAME
459
460 void
scm_dynwind_current_output_port(SCM port)461 scm_dynwind_current_output_port (SCM port)
462 #define FUNC_NAME NULL
463 {
464 port = SCM_COERCE_OUTPORT (port);
465 SCM_VALIDATE_OPOUTPORT (1, port);
466 scm_dynwind_fluid (cur_outport_fluid, port);
467 }
468 #undef FUNC_NAME
469
470 void
scm_dynwind_current_error_port(SCM port)471 scm_dynwind_current_error_port (SCM port)
472 #define FUNC_NAME NULL
473 {
474 port = SCM_COERCE_OUTPORT (port);
475 SCM_VALIDATE_OPOUTPORT (1, port);
476 scm_dynwind_fluid (cur_errport_fluid, port);
477 }
478 #undef FUNC_NAME
479
480 void
scm_i_dynwind_current_load_port(SCM port)481 scm_i_dynwind_current_load_port (SCM port)
482 {
483 scm_dynwind_fluid (cur_loadport_fluid, port);
484 }
485
486
487 /* The port table --- an array of pointers to ports. */
488
489 scm_t_port **scm_i_port_table;
490
491 long scm_i_port_table_size = 0; /* Number of ports in scm_i_port_table. */
492 long scm_i_port_table_room = 20; /* Size of the array. */
493
494 scm_i_pthread_mutex_t scm_i_port_table_mutex = SCM_I_PTHREAD_MUTEX_INITIALIZER;
495
496 /* This function is not and should not be thread safe. */
497
498 SCM
scm_new_port_table_entry(scm_t_bits tag)499 scm_new_port_table_entry (scm_t_bits tag)
500 #define FUNC_NAME "scm_new_port_table_entry"
501 {
502 /*
503 We initialize the cell to empty, this is in case scm_gc_calloc
504 triggers GC ; we don't want the GC to scan a half-finished Z.
505 */
506
507 SCM z = scm_cons (SCM_EOL, SCM_EOL);
508 scm_t_port *entry = (scm_t_port *) scm_gc_calloc (sizeof (scm_t_port), "port");
509 if (scm_i_port_table_size == scm_i_port_table_room)
510 {
511 /* initial malloc is in gc.c. this doesn't use scm_gc_malloc etc.,
512 since it can never be freed during gc. */
513 void *newt = scm_realloc ((char *) scm_i_port_table,
514 (size_t) (sizeof (scm_t_port *)
515 * scm_i_port_table_room * 2));
516 scm_i_port_table = (scm_t_port **) newt;
517 scm_i_port_table_room *= 2;
518 }
519
520 entry->entry = scm_i_port_table_size;
521
522 entry->file_name = SCM_BOOL_F;
523 entry->rw_active = SCM_PORT_NEITHER;
524
525 scm_i_port_table[scm_i_port_table_size] = entry;
526 scm_i_port_table_size++;
527
528 entry->port = z;
529 SCM_SET_CELL_TYPE(z, tag);
530 SCM_SETPTAB_ENTRY(z, entry);
531
532 return z;
533 }
534 #undef FUNC_NAME
535
536 #if SCM_ENABLE_DEPRECATED==1
537 SCM_API scm_t_port *
scm_add_to_port_table(SCM port)538 scm_add_to_port_table (SCM port)
539 {
540 SCM z = scm_new_port_table_entry (scm_tc7_port);
541 scm_t_port * pt = SCM_PTAB_ENTRY(z);
542
543 pt->port = port;
544 SCM_SETCAR(z, SCM_EOL);
545 SCM_SETCDR(z, SCM_EOL);
546 SCM_SETPTAB_ENTRY (port, pt);
547 return pt;
548 }
549 #endif
550
551
552 /* Remove a port from the table and destroy it. */
553
554 /* This function is not and should not be thread safe. */
555
556 void
scm_remove_from_port_table(SCM port)557 scm_remove_from_port_table (SCM port)
558 #define FUNC_NAME "scm_remove_from_port_table"
559 {
560 scm_t_port *p = SCM_PTAB_ENTRY (port);
561 long i = p->entry;
562
563 if (i >= scm_i_port_table_size)
564 SCM_MISC_ERROR ("Port not in table: ~S", scm_list_1 (port));
565 if (p->putback_buf)
566 scm_gc_free (p->putback_buf, p->putback_buf_size, "putback buffer");
567 scm_gc_free (p, sizeof (scm_t_port), "port");
568 /* Since we have just freed slot i we can shrink the table by moving
569 the last entry to that slot... */
570 if (i < scm_i_port_table_size - 1)
571 {
572 scm_i_port_table[i] = scm_i_port_table[scm_i_port_table_size - 1];
573 scm_i_port_table[i]->entry = i;
574 }
575 SCM_SETPTAB_ENTRY (port, 0);
576 scm_i_port_table_size--;
577 }
578 #undef FUNC_NAME
579
580
581 #ifdef GUILE_DEBUG
582 /* Functions for debugging. */
583
584 SCM_DEFINE (scm_pt_size, "pt-size", 0, 0, 0,
585 (),
586 "Return the number of ports in the port table. @code{pt-size}\n"
587 "is only included in @code{--enable-guile-debug} builds.")
588 #define FUNC_NAME s_scm_pt_size
589 {
590 return scm_from_int (scm_i_port_table_size);
591 }
592 #undef FUNC_NAME
593
594 SCM_DEFINE (scm_pt_member, "pt-member", 1, 0, 0,
595 (SCM index),
596 "Return the port at @var{index} in the port table.\n"
597 "@code{pt-member} is only included in\n"
598 "@code{--enable-guile-debug} builds.")
599 #define FUNC_NAME s_scm_pt_member
600 {
601 size_t i = scm_to_size_t (index);
602 if (i >= scm_i_port_table_size)
603 return SCM_BOOL_F;
604 else
605 return scm_i_port_table[i]->port;
606 }
607 #undef FUNC_NAME
608 #endif
609
610 void
scm_port_non_buffer(scm_t_port * pt)611 scm_port_non_buffer (scm_t_port *pt)
612 {
613 pt->read_pos = pt->read_buf = pt->read_end = &pt->shortbuf;
614 pt->write_buf = pt->write_pos = &pt->shortbuf;
615 pt->read_buf_size = pt->write_buf_size = 1;
616 pt->write_end = pt->write_buf + pt->write_buf_size;
617 }
618
619
620 /* Revealed counts --- an oddity inherited from SCSH. */
621
622 /* Find a port in the table and return its revealed count.
623 Also used by the garbage collector.
624 */
625
626 int
scm_revealed_count(SCM port)627 scm_revealed_count (SCM port)
628 {
629 return SCM_REVEALED(port);
630 }
631
632
633
634 /* Return the revealed count for a port. */
635
636 SCM_DEFINE (scm_port_revealed, "port-revealed", 1, 0, 0,
637 (SCM port),
638 "Return the revealed count for @var{port}.")
639 #define FUNC_NAME s_scm_port_revealed
640 {
641 port = SCM_COERCE_OUTPORT (port);
642 SCM_VALIDATE_OPENPORT (1, port);
643 return scm_from_int (scm_revealed_count (port));
644 }
645 #undef FUNC_NAME
646
647 /* Set the revealed count for a port. */
648 SCM_DEFINE (scm_set_port_revealed_x, "set-port-revealed!", 2, 0, 0,
649 (SCM port, SCM rcount),
650 "Sets the revealed count for a port to a given value.\n"
651 "The return value is unspecified.")
652 #define FUNC_NAME s_scm_set_port_revealed_x
653 {
654 port = SCM_COERCE_OUTPORT (port);
655 SCM_VALIDATE_OPENPORT (1, port);
656 SCM_REVEALED (port) = scm_to_int (rcount);
657 return SCM_UNSPECIFIED;
658 }
659 #undef FUNC_NAME
660
661
662
663 /* Retrieving a port's mode. */
664
665 /* Return the flags that characterize a port based on the mode
666 * string used to open a file for that port.
667 *
668 * See PORT FLAGS in scm.h
669 */
670
671 static long
scm_i_mode_bits_n(const char * modes,size_t n)672 scm_i_mode_bits_n (const char *modes, size_t n)
673 {
674 return (SCM_OPN
675 | (memchr (modes, 'r', n) || memchr (modes, '+', n) ? SCM_RDNG : 0)
676 | ( memchr (modes, 'w', n)
677 || memchr (modes, 'a', n)
678 || memchr (modes, '+', n) ? SCM_WRTNG : 0)
679 | (memchr (modes, '0', n) ? SCM_BUF0 : 0)
680 | (memchr (modes, 'l', n) ? SCM_BUFLINE : 0));
681 }
682
683 long
scm_mode_bits(char * modes)684 scm_mode_bits (char *modes)
685 {
686 return scm_i_mode_bits_n (modes, strlen (modes));
687 }
688
689 long
scm_i_mode_bits(SCM modes)690 scm_i_mode_bits (SCM modes)
691 {
692 long bits;
693
694 if (!scm_is_string (modes))
695 scm_wrong_type_arg_msg (NULL, 0, modes, "string");
696
697 bits = scm_i_mode_bits_n (scm_i_string_chars (modes),
698 scm_i_string_length (modes));
699 scm_remember_upto_here_1 (modes);
700 return bits;
701 }
702
703 /* Return the mode flags from an open port.
704 * Some modes such as "append" are only used when opening
705 * a file and are not returned here. */
706
707 SCM_DEFINE (scm_port_mode, "port-mode", 1, 0, 0,
708 (SCM port),
709 "Return the port modes associated with the open port @var{port}.\n"
710 "These will not necessarily be identical to the modes used when\n"
711 "the port was opened, since modes such as \"append\" which are\n"
712 "used only during port creation are not retained.")
713 #define FUNC_NAME s_scm_port_mode
714 {
715 char modes[4];
716 modes[0] = '\0';
717
718 port = SCM_COERCE_OUTPORT (port);
719 SCM_VALIDATE_OPPORT (1, port);
720 if (SCM_CELL_WORD_0 (port) & SCM_RDNG) {
721 if (SCM_CELL_WORD_0 (port) & SCM_WRTNG)
722 strcpy (modes, "r+");
723 else
724 strcpy (modes, "r");
725 }
726 else if (SCM_CELL_WORD_0 (port) & SCM_WRTNG)
727 strcpy (modes, "w");
728 if (SCM_CELL_WORD_0 (port) & SCM_BUF0)
729 strcat (modes, "0");
730 return scm_from_locale_string (modes);
731 }
732 #undef FUNC_NAME
733
734
735
736 /* Closing ports. */
737
738 /* scm_close_port
739 * Call the close operation on a port object.
740 * see also scm_close.
741 */
742 SCM_DEFINE (scm_close_port, "close-port", 1, 0, 0,
743 (SCM port),
744 "Close the specified port object. Return @code{#t} if it\n"
745 "successfully closes a port or @code{#f} if it was already\n"
746 "closed. An exception may be raised if an error occurs, for\n"
747 "example when flushing buffered output. See also @ref{Ports and\n"
748 "File Descriptors, close}, for a procedure which can close file\n"
749 "descriptors.")
750 #define FUNC_NAME s_scm_close_port
751 {
752 size_t i;
753 int rv;
754
755 port = SCM_COERCE_OUTPORT (port);
756
757 SCM_VALIDATE_PORT (1, port);
758 if (SCM_CLOSEDP (port))
759 return SCM_BOOL_F;
760 i = SCM_PTOBNUM (port);
761 if (scm_ptobs[i].close)
762 rv = (scm_ptobs[i].close) (port);
763 else
764 rv = 0;
765 scm_i_scm_pthread_mutex_lock (&scm_i_port_table_mutex);
766 scm_remove_from_port_table (port);
767 scm_i_pthread_mutex_unlock (&scm_i_port_table_mutex);
768 SCM_CLR_PORT_OPEN_FLAG (port);
769 return scm_from_bool (rv >= 0);
770 }
771 #undef FUNC_NAME
772
773 SCM_DEFINE (scm_close_input_port, "close-input-port", 1, 0, 0,
774 (SCM port),
775 "Close the specified input port object. The routine has no effect if\n"
776 "the file has already been closed. An exception may be raised if an\n"
777 "error occurs. The value returned is unspecified.\n\n"
778 "See also @ref{Ports and File Descriptors, close}, for a procedure\n"
779 "which can close file descriptors.")
780 #define FUNC_NAME s_scm_close_input_port
781 {
782 SCM_VALIDATE_INPUT_PORT (1, port);
783 scm_close_port (port);
784 return SCM_UNSPECIFIED;
785 }
786 #undef FUNC_NAME
787
788 SCM_DEFINE (scm_close_output_port, "close-output-port", 1, 0, 0,
789 (SCM port),
790 "Close the specified output port object. The routine has no effect if\n"
791 "the file has already been closed. An exception may be raised if an\n"
792 "error occurs. The value returned is unspecified.\n\n"
793 "See also @ref{Ports and File Descriptors, close}, for a procedure\n"
794 "which can close file descriptors.")
795 #define FUNC_NAME s_scm_close_output_port
796 {
797 port = SCM_COERCE_OUTPORT (port);
798 SCM_VALIDATE_OUTPUT_PORT (1, port);
799 scm_close_port (port);
800 return SCM_UNSPECIFIED;
801 }
802 #undef FUNC_NAME
803
804 void
scm_c_port_for_each(void (* proc)(void * data,SCM p),void * data)805 scm_c_port_for_each (void (*proc)(void *data, SCM p), void *data)
806 {
807 long i;
808 size_t n;
809 SCM ports;
810
811 /* Even without pre-emptive multithreading, running arbitrary code
812 while scanning the port table is unsafe because the port table
813 can change arbitrarily (from a GC, for example). So we first
814 collect the ports into a vector. -mvo */
815
816 scm_i_scm_pthread_mutex_lock (&scm_i_port_table_mutex);
817 n = scm_i_port_table_size;
818 scm_i_pthread_mutex_unlock (&scm_i_port_table_mutex);
819
820 ports = scm_c_make_vector (n, SCM_BOOL_F);
821
822 scm_i_scm_pthread_mutex_lock (&scm_i_port_table_mutex);
823 if (n > scm_i_port_table_size)
824 n = scm_i_port_table_size;
825 for (i = 0; i < n; i++)
826 SCM_SIMPLE_VECTOR_SET (ports, i, scm_i_port_table[i]->port);
827 scm_i_pthread_mutex_unlock (&scm_i_port_table_mutex);
828
829 for (i = 0; i < n; i++)
830 proc (data, SCM_SIMPLE_VECTOR_REF (ports, i));
831
832 scm_remember_upto_here_1 (ports);
833 }
834
835 SCM_DEFINE (scm_port_for_each, "port-for-each", 1, 0, 0,
836 (SCM proc),
837 "Apply @var{proc} to each port in the Guile port table\n"
838 "in turn. The return value is unspecified. More specifically,\n"
839 "@var{proc} is applied exactly once to every port that exists\n"
840 "in the system at the time @var{port-for-each} is invoked.\n"
841 "Changes to the port table while @var{port-for-each} is running\n"
842 "have no effect as far as @var{port-for-each} is concerned.")
843 #define FUNC_NAME s_scm_port_for_each
844 {
845 SCM_VALIDATE_PROC (1, proc);
846
847 scm_c_port_for_each ((void (*)(void*,SCM))scm_call_1, proc);
848 return SCM_UNSPECIFIED;
849 }
850 #undef FUNC_NAME
851
852
853
854 /* Utter miscellany. Gosh, we should clean this up some time. */
855
856 SCM_DEFINE (scm_input_port_p, "input-port?", 1, 0, 0,
857 (SCM x),
858 "Return @code{#t} if @var{x} is an input port, otherwise return\n"
859 "@code{#f}. Any object satisfying this predicate also satisfies\n"
860 "@code{port?}.")
861 #define FUNC_NAME s_scm_input_port_p
862 {
863 return scm_from_bool (SCM_INPUT_PORT_P (x));
864 }
865 #undef FUNC_NAME
866
867 SCM_DEFINE (scm_output_port_p, "output-port?", 1, 0, 0,
868 (SCM x),
869 "Return @code{#t} if @var{x} is an output port, otherwise return\n"
870 "@code{#f}. Any object satisfying this predicate also satisfies\n"
871 "@code{port?}.")
872 #define FUNC_NAME s_scm_output_port_p
873 {
874 x = SCM_COERCE_OUTPORT (x);
875 return scm_from_bool (SCM_OUTPUT_PORT_P (x));
876 }
877 #undef FUNC_NAME
878
879 SCM_DEFINE (scm_port_p, "port?", 1, 0, 0,
880 (SCM x),
881 "Return a boolean indicating whether @var{x} is a port.\n"
882 "Equivalent to @code{(or (input-port? @var{x}) (output-port?\n"
883 "@var{x}))}.")
884 #define FUNC_NAME s_scm_port_p
885 {
886 return scm_from_bool (SCM_PORTP (x));
887 }
888 #undef FUNC_NAME
889
890 SCM_DEFINE (scm_port_closed_p, "port-closed?", 1, 0, 0,
891 (SCM port),
892 "Return @code{#t} if @var{port} is closed or @code{#f} if it is\n"
893 "open.")
894 #define FUNC_NAME s_scm_port_closed_p
895 {
896 SCM_VALIDATE_PORT (1, port);
897 return scm_from_bool (!SCM_OPPORTP (port));
898 }
899 #undef FUNC_NAME
900
901 SCM_DEFINE (scm_eof_object_p, "eof-object?", 1, 0, 0,
902 (SCM x),
903 "Return @code{#t} if @var{x} is an end-of-file object; otherwise\n"
904 "return @code{#f}.")
905 #define FUNC_NAME s_scm_eof_object_p
906 {
907 return scm_from_bool(SCM_EOF_OBJECT_P (x));
908 }
909 #undef FUNC_NAME
910
911 SCM_DEFINE (scm_force_output, "force-output", 0, 1, 0,
912 (SCM port),
913 "Flush the specified output port, or the current output port if @var{port}\n"
914 "is omitted. The current output buffer contents are passed to the\n"
915 "underlying port implementation (e.g., in the case of fports, the\n"
916 "data will be written to the file and the output buffer will be cleared.)\n"
917 "It has no effect on an unbuffered port.\n\n"
918 "The return value is unspecified.")
919 #define FUNC_NAME s_scm_force_output
920 {
921 if (SCM_UNBNDP (port))
922 port = scm_current_output_port ();
923 else
924 {
925 port = SCM_COERCE_OUTPORT (port);
926 SCM_VALIDATE_OPOUTPORT (1, port);
927 }
928 scm_flush (port);
929 return SCM_UNSPECIFIED;
930 }
931 #undef FUNC_NAME
932
933 SCM_DEFINE (scm_flush_all_ports, "flush-all-ports", 0, 0, 0,
934 (),
935 "Equivalent to calling @code{force-output} on\n"
936 "all open output ports. The return value is unspecified.")
937 #define FUNC_NAME s_scm_flush_all_ports
938 {
939 size_t i;
940
941 scm_i_scm_pthread_mutex_lock (&scm_i_port_table_mutex);
942 for (i = 0; i < scm_i_port_table_size; i++)
943 {
944 if (SCM_OPOUTPORTP (scm_i_port_table[i]->port))
945 scm_flush (scm_i_port_table[i]->port);
946 }
947 scm_i_pthread_mutex_unlock (&scm_i_port_table_mutex);
948 return SCM_UNSPECIFIED;
949 }
950 #undef FUNC_NAME
951
952 SCM_DEFINE (scm_read_char, "read-char", 0, 1, 0,
953 (SCM port),
954 "Return the next character available from @var{port}, updating\n"
955 "@var{port} to point to the following character. If no more\n"
956 "characters are available, the end-of-file object is returned.")
957 #define FUNC_NAME s_scm_read_char
958 {
959 int c;
960 if (SCM_UNBNDP (port))
961 port = scm_current_input_port ();
962 SCM_VALIDATE_OPINPORT (1, port);
963 c = scm_getc (port);
964 if (EOF == c)
965 return SCM_EOF_VAL;
966 return SCM_MAKE_CHAR (c);
967 }
968 #undef FUNC_NAME
969
970 /* this should only be called when the read buffer is empty. it
971 tries to refill the read buffer. it returns the first char from
972 the port, which is either EOF or *(pt->read_pos). */
973 int
scm_fill_input(SCM port)974 scm_fill_input (SCM port)
975 {
976 scm_t_port *pt = SCM_PTAB_ENTRY (port);
977
978 assert (pt->read_pos == pt->read_end);
979
980 if (pt->read_buf == pt->putback_buf)
981 {
982 /* finished reading put-back chars. */
983 pt->read_buf = pt->saved_read_buf;
984 pt->read_pos = pt->saved_read_pos;
985 pt->read_end = pt->saved_read_end;
986 pt->read_buf_size = pt->saved_read_buf_size;
987 if (pt->read_pos < pt->read_end)
988 return *(pt->read_pos);
989 }
990 return scm_ptobs[SCM_PTOBNUM (port)].fill_input (port);
991 }
992
993
994 /* scm_lfwrite
995 *
996 * This function differs from scm_c_write; it updates port line and
997 * column. */
998
999 void
scm_lfwrite(const char * ptr,size_t size,SCM port)1000 scm_lfwrite (const char *ptr, size_t size, SCM port)
1001 {
1002 scm_t_port *pt = SCM_PTAB_ENTRY (port);
1003 scm_t_ptob_descriptor *ptob = &scm_ptobs[SCM_PTOBNUM (port)];
1004
1005 if (pt->rw_active == SCM_PORT_READ)
1006 scm_end_input (port);
1007
1008 ptob->write (port, ptr, size);
1009
1010 for (; size; ptr++, size--) {
1011 if (*ptr == '\a') {
1012 }
1013 else if (*ptr == '\b') {
1014 SCM_DECCOL(port);
1015 }
1016 else if (*ptr == '\n') {
1017 SCM_INCLINE(port);
1018 }
1019 else if (*ptr == '\r') {
1020 SCM_ZEROCOL(port);
1021 }
1022 else if (*ptr == '\t') {
1023 SCM_TABCOL(port);
1024 }
1025 else {
1026 SCM_INCCOL(port);
1027 }
1028 }
1029
1030 if (pt->rw_random)
1031 pt->rw_active = SCM_PORT_WRITE;
1032 }
1033
1034 /* scm_c_read
1035 *
1036 * Used by an application to read arbitrary number of bytes from an
1037 * SCM port. Same semantics as libc read, except that scm_c_read only
1038 * returns less than SIZE bytes if at end-of-file.
1039 *
1040 * Warning: Doesn't update port line and column counts! */
1041
1042 /* This structure, and the following swap_buffer function, are used
1043 for temporarily swapping a port's own read buffer, and the buffer
1044 that the caller of scm_c_read provides. */
1045 struct port_and_swap_buffer
1046 {
1047 scm_t_port *pt;
1048 unsigned char *buffer;
1049 size_t size;
1050 };
1051
1052 static void
swap_buffer(void * data)1053 swap_buffer (void *data)
1054 {
1055 struct port_and_swap_buffer *psb = (struct port_and_swap_buffer *) data;
1056 unsigned char *old_buf = psb->pt->read_buf;
1057 size_t old_size = psb->pt->read_buf_size;
1058
1059 /* Make the port use (buffer, size) from the struct. */
1060 psb->pt->read_pos = psb->pt->read_buf = psb->pt->read_end = psb->buffer;
1061 psb->pt->read_buf_size = psb->size;
1062
1063 /* Save the port's old (buffer, size) in the struct. */
1064 psb->buffer = old_buf;
1065 psb->size = old_size;
1066 }
1067
1068 size_t
scm_c_read(SCM port,void * buffer,size_t size)1069 scm_c_read (SCM port, void *buffer, size_t size)
1070 #define FUNC_NAME "scm_c_read"
1071 {
1072 scm_t_port *pt;
1073 size_t n_read = 0, n_available;
1074 struct port_and_swap_buffer psb;
1075
1076 SCM_VALIDATE_OPINPORT (1, port);
1077
1078 pt = SCM_PTAB_ENTRY (port);
1079 if (pt->rw_active == SCM_PORT_WRITE)
1080 scm_ptobs[SCM_PTOBNUM (port)].flush (port);
1081
1082 if (pt->rw_random)
1083 pt->rw_active = SCM_PORT_READ;
1084
1085 /* Take bytes first from the port's read buffer. */
1086 if (pt->read_pos < pt->read_end)
1087 {
1088 n_available = min (size, pt->read_end - pt->read_pos);
1089 memcpy (buffer, pt->read_pos, n_available);
1090 buffer = (char *) buffer + n_available;
1091 pt->read_pos += n_available;
1092 n_read += n_available;
1093 size -= n_available;
1094 }
1095
1096 /* Avoid the scm_dynwind_* costs if we now have enough data. */
1097 if (size == 0)
1098 return n_read;
1099
1100 /* Now we will call scm_fill_input repeatedly until we have read the
1101 requested number of bytes. (Note that a single scm_fill_input
1102 call does not guarantee to fill the whole of the port's read
1103 buffer.) */
1104 if (pt->read_buf_size <= 1)
1105 {
1106 /* The port that we are reading from is unbuffered - i.e. does
1107 not have its own persistent buffer - but we have a buffer,
1108 provided by our caller, that is the right size for the data
1109 that is wanted. For the following scm_fill_input calls,
1110 therefore, we use the buffer in hand as the port's read
1111 buffer.
1112
1113 We need to make sure that the port's normal (1 byte) buffer
1114 is reinstated in case one of the scm_fill_input () calls
1115 throws an exception; we use the scm_dynwind_* API to achieve
1116 that. */
1117 psb.pt = pt;
1118 psb.buffer = buffer;
1119 psb.size = size;
1120 scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
1121 scm_dynwind_rewind_handler (swap_buffer, &psb, SCM_F_WIND_EXPLICITLY);
1122 scm_dynwind_unwind_handler (swap_buffer, &psb, SCM_F_WIND_EXPLICITLY);
1123
1124 /* Call scm_fill_input until we have all the bytes that we need,
1125 or we hit EOF. */
1126 while (pt->read_buf_size && (scm_fill_input (port) != EOF))
1127 {
1128 pt->read_buf_size -= (pt->read_end - pt->read_pos);
1129 pt->read_pos = pt->read_buf = pt->read_end;
1130 }
1131 n_read += pt->read_buf - (unsigned char *) buffer;
1132
1133 /* Reinstate the port's normal buffer. */
1134 scm_dynwind_end ();
1135 }
1136 else
1137 {
1138 /* The port has its own buffer. It is important that we use it,
1139 even if it happens to be smaller than our caller's buffer, so
1140 that a custom port implementation's entry points (in
1141 particular, fill_input) can rely on the buffer always being
1142 the same as they first set up. */
1143 while (size && (scm_fill_input (port) != EOF))
1144 {
1145 n_available = min (size, pt->read_end - pt->read_pos);
1146 memcpy (buffer, pt->read_pos, n_available);
1147 buffer = (char *) buffer + n_available;
1148 pt->read_pos += n_available;
1149 n_read += n_available;
1150 size -= n_available;
1151 }
1152 }
1153
1154 return n_read;
1155 }
1156 #undef FUNC_NAME
1157
1158 /* scm_c_write
1159 *
1160 * Used by an application to write arbitrary number of bytes to an SCM
1161 * port. Similar semantics as libc write. However, unlike libc
1162 * write, scm_c_write writes the requested number of bytes and has no
1163 * return value.
1164 *
1165 * Warning: Doesn't update port line and column counts!
1166 */
1167
1168 void
scm_c_write(SCM port,const void * ptr,size_t size)1169 scm_c_write (SCM port, const void *ptr, size_t size)
1170 #define FUNC_NAME "scm_c_write"
1171 {
1172 scm_t_port *pt;
1173 scm_t_ptob_descriptor *ptob;
1174
1175 SCM_VALIDATE_OPOUTPORT (1, port);
1176
1177 pt = SCM_PTAB_ENTRY (port);
1178 ptob = &scm_ptobs[SCM_PTOBNUM (port)];
1179
1180 if (pt->rw_active == SCM_PORT_READ)
1181 scm_end_input (port);
1182
1183 ptob->write (port, ptr, size);
1184
1185 if (pt->rw_random)
1186 pt->rw_active = SCM_PORT_WRITE;
1187 }
1188 #undef FUNC_NAME
1189
1190 void
scm_flush(SCM port)1191 scm_flush (SCM port)
1192 {
1193 long i = SCM_PTOBNUM (port);
1194 (scm_ptobs[i].flush) (port);
1195 }
1196
1197 void
scm_end_input(SCM port)1198 scm_end_input (SCM port)
1199 {
1200 long offset;
1201 scm_t_port *pt = SCM_PTAB_ENTRY (port);
1202
1203 if (pt->read_buf == pt->putback_buf)
1204 {
1205 offset = pt->read_end - pt->read_pos;
1206 pt->read_buf = pt->saved_read_buf;
1207 pt->read_pos = pt->saved_read_pos;
1208 pt->read_end = pt->saved_read_end;
1209 pt->read_buf_size = pt->saved_read_buf_size;
1210 }
1211 else
1212 offset = 0;
1213
1214 scm_ptobs[SCM_PTOBNUM (port)].end_input (port, offset);
1215 }
1216
1217
1218
1219
1220 void
scm_ungetc(int c,SCM port)1221 scm_ungetc (int c, SCM port)
1222 #define FUNC_NAME "scm_ungetc"
1223 {
1224 scm_t_port *pt = SCM_PTAB_ENTRY (port);
1225
1226 if (pt->read_buf == pt->putback_buf)
1227 /* already using the put-back buffer. */
1228 {
1229 /* enlarge putback_buf if necessary. */
1230 if (pt->read_end == pt->read_buf + pt->read_buf_size
1231 && pt->read_buf == pt->read_pos)
1232 {
1233 size_t new_size = pt->read_buf_size * 2;
1234 unsigned char *tmp = (unsigned char *)
1235 scm_gc_realloc (pt->putback_buf, pt->read_buf_size, new_size,
1236 "putback buffer");
1237
1238 pt->read_pos = pt->read_buf = pt->putback_buf = tmp;
1239 pt->read_end = pt->read_buf + pt->read_buf_size;
1240 pt->read_buf_size = pt->putback_buf_size = new_size;
1241 }
1242
1243 /* shift any existing bytes to buffer + 1. */
1244 if (pt->read_pos == pt->read_end)
1245 pt->read_end = pt->read_buf + 1;
1246 else if (pt->read_pos != pt->read_buf + 1)
1247 {
1248 int count = pt->read_end - pt->read_pos;
1249
1250 memmove (pt->read_buf + 1, pt->read_pos, count);
1251 pt->read_end = pt->read_buf + 1 + count;
1252 }
1253
1254 pt->read_pos = pt->read_buf;
1255 }
1256 else
1257 /* switch to the put-back buffer. */
1258 {
1259 if (pt->putback_buf == NULL)
1260 {
1261 pt->putback_buf
1262 = (unsigned char *) scm_gc_malloc (SCM_INITIAL_PUTBACK_BUF_SIZE,
1263 "putback buffer");
1264 pt->putback_buf_size = SCM_INITIAL_PUTBACK_BUF_SIZE;
1265 }
1266
1267 pt->saved_read_buf = pt->read_buf;
1268 pt->saved_read_pos = pt->read_pos;
1269 pt->saved_read_end = pt->read_end;
1270 pt->saved_read_buf_size = pt->read_buf_size;
1271
1272 pt->read_pos = pt->read_buf = pt->putback_buf;
1273 pt->read_end = pt->read_buf + 1;
1274 pt->read_buf_size = pt->putback_buf_size;
1275 }
1276
1277 *pt->read_buf = c;
1278
1279 if (pt->rw_random)
1280 pt->rw_active = SCM_PORT_READ;
1281
1282 if (c == '\n')
1283 {
1284 /* What should col be in this case?
1285 * We'll leave it at -1.
1286 */
1287 SCM_LINUM (port) -= 1;
1288 }
1289 else
1290 SCM_COL(port) -= 1;
1291 }
1292 #undef FUNC_NAME
1293
1294
1295 void
scm_ungets(const char * s,int n,SCM port)1296 scm_ungets (const char *s, int n, SCM port)
1297 {
1298 /* This is simple minded and inefficient, but unreading strings is
1299 * probably not a common operation, and remember that line and
1300 * column numbers have to be handled...
1301 *
1302 * Please feel free to write an optimized version!
1303 */
1304 while (n--)
1305 scm_ungetc (s[n], port);
1306 }
1307
1308
1309 SCM_DEFINE (scm_peek_char, "peek-char", 0, 1, 0,
1310 (SCM port),
1311 "Return the next character available from @var{port},\n"
1312 "@emph{without} updating @var{port} to point to the following\n"
1313 "character. If no more characters are available, the\n"
1314 "end-of-file object is returned.\n"
1315 "\n"
1316 "The value returned by\n"
1317 "a call to @code{peek-char} is the same as the value that would\n"
1318 "have been returned by a call to @code{read-char} on the same\n"
1319 "port. The only difference is that the very next call to\n"
1320 "@code{read-char} or @code{peek-char} on that @var{port} will\n"
1321 "return the value returned by the preceding call to\n"
1322 "@code{peek-char}. In particular, a call to @code{peek-char} on\n"
1323 "an interactive port will hang waiting for input whenever a call\n"
1324 "to @code{read-char} would have hung.")
1325 #define FUNC_NAME s_scm_peek_char
1326 {
1327 int c, column;
1328 if (SCM_UNBNDP (port))
1329 port = scm_current_input_port ();
1330 else
1331 SCM_VALIDATE_OPINPORT (1, port);
1332 column = SCM_COL(port);
1333 c = scm_getc (port);
1334 if (EOF == c)
1335 return SCM_EOF_VAL;
1336 scm_ungetc (c, port);
1337 SCM_COL(port) = column;
1338 return SCM_MAKE_CHAR (c);
1339 }
1340 #undef FUNC_NAME
1341
1342 SCM_DEFINE (scm_unread_char, "unread-char", 1, 1, 0,
1343 (SCM cobj, SCM port),
1344 "Place @var{char} in @var{port} so that it will be read by the\n"
1345 "next read operation. If called multiple times, the unread characters\n"
1346 "will be read again in last-in first-out order. If @var{port} is\n"
1347 "not supplied, the current input port is used.")
1348 #define FUNC_NAME s_scm_unread_char
1349 {
1350 int c;
1351
1352 SCM_VALIDATE_CHAR (1, cobj);
1353 if (SCM_UNBNDP (port))
1354 port = scm_current_input_port ();
1355 else
1356 SCM_VALIDATE_OPINPORT (2, port);
1357
1358 c = SCM_CHAR (cobj);
1359
1360 scm_ungetc (c, port);
1361 return cobj;
1362 }
1363 #undef FUNC_NAME
1364
1365 SCM_DEFINE (scm_unread_string, "unread-string", 2, 0, 0,
1366 (SCM str, SCM port),
1367 "Place the string @var{str} in @var{port} so that its characters will be\n"
1368 "read in subsequent read operations. If called multiple times, the\n"
1369 "unread characters will be read again in last-in first-out order. If\n"
1370 "@var{port} is not supplied, the current-input-port is used.")
1371 #define FUNC_NAME s_scm_unread_string
1372 {
1373 SCM_VALIDATE_STRING (1, str);
1374 if (SCM_UNBNDP (port))
1375 port = scm_current_input_port ();
1376 else
1377 SCM_VALIDATE_OPINPORT (2, port);
1378
1379 scm_ungets (scm_i_string_chars (str), scm_i_string_length (str), port);
1380
1381 return str;
1382 }
1383 #undef FUNC_NAME
1384
1385 SCM_DEFINE (scm_seek, "seek", 3, 0, 0,
1386 (SCM fd_port, SCM offset, SCM whence),
1387 "Sets the current position of @var{fd/port} to the integer\n"
1388 "@var{offset}, which is interpreted according to the value of\n"
1389 "@var{whence}.\n"
1390 "\n"
1391 "One of the following variables should be supplied for\n"
1392 "@var{whence}:\n"
1393 "@defvar SEEK_SET\n"
1394 "Seek from the beginning of the file.\n"
1395 "@end defvar\n"
1396 "@defvar SEEK_CUR\n"
1397 "Seek from the current position.\n"
1398 "@end defvar\n"
1399 "@defvar SEEK_END\n"
1400 "Seek from the end of the file.\n"
1401 "@end defvar\n"
1402 "If @var{fd/port} is a file descriptor, the underlying system\n"
1403 "call is @code{lseek}. @var{port} may be a string port.\n"
1404 "\n"
1405 "The value returned is the new position in the file. This means\n"
1406 "that the current position of a port can be obtained using:\n"
1407 "@lisp\n"
1408 "(seek port 0 SEEK_CUR)\n"
1409 "@end lisp")
1410 #define FUNC_NAME s_scm_seek
1411 {
1412 int how;
1413
1414 fd_port = SCM_COERCE_OUTPORT (fd_port);
1415
1416 how = scm_to_int (whence);
1417 if (how != SEEK_SET && how != SEEK_CUR && how != SEEK_END)
1418 SCM_OUT_OF_RANGE (3, whence);
1419
1420 if (SCM_OPFPORTP (fd_port))
1421 {
1422 /* go direct to fport code to allow 64-bit offsets */
1423 return scm_i_fport_seek (fd_port, offset, how);
1424 }
1425 else if (SCM_OPPORTP (fd_port))
1426 {
1427 scm_t_ptob_descriptor *ptob = scm_ptobs + SCM_PTOBNUM (fd_port);
1428 off_t off = scm_to_off_t (offset);
1429 off_t rv;
1430
1431 if (!ptob->seek)
1432 SCM_MISC_ERROR ("port is not seekable",
1433 scm_cons (fd_port, SCM_EOL));
1434 else
1435 rv = ptob->seek (fd_port, off, how);
1436 return scm_from_off_t (rv);
1437 }
1438 else /* file descriptor?. */
1439 {
1440 off_t_or_off64_t off = scm_to_off_t_or_off64_t (offset);
1441 off_t_or_off64_t rv;
1442 rv = lseek_or_lseek64 (scm_to_int (fd_port), off, how);
1443 if (rv == -1)
1444 SCM_SYSERROR;
1445 return scm_from_off_t_or_off64_t (rv);
1446 }
1447 }
1448 #undef FUNC_NAME
1449
1450 #ifndef O_BINARY
1451 #define O_BINARY 0
1452 #endif
1453
1454 /* Mingw has ftruncate(), perhaps implemented above using chsize, but
1455 doesn't have the filename version truncate(), hence this code. */
1456 #if HAVE_FTRUNCATE && ! HAVE_TRUNCATE
1457 static int
truncate(const char * file,off_t length)1458 truncate (const char *file, off_t length)
1459 {
1460 int ret, fdes;
1461
1462 fdes = open (file, O_BINARY | O_WRONLY);
1463 if (fdes == -1)
1464 return -1;
1465
1466 ret = ftruncate (fdes, length);
1467 if (ret == -1)
1468 {
1469 int save_errno = errno;
1470 close (fdes);
1471 errno = save_errno;
1472 return -1;
1473 }
1474
1475 return close (fdes);
1476 }
1477 #endif /* HAVE_FTRUNCATE && ! HAVE_TRUNCATE */
1478
1479 SCM_DEFINE (scm_truncate_file, "truncate-file", 1, 1, 0,
1480 (SCM object, SCM length),
1481 "Truncate @var{file} to @var{length} bytes. @var{file} can be a\n"
1482 "filename string, a port object, or an integer file descriptor.\n"
1483 "The return value is unspecified.\n"
1484 "\n"
1485 "For a port or file descriptor @var{length} can be omitted, in\n"
1486 "which case the file is truncated at the current position (per\n"
1487 "@code{ftell} above).\n"
1488 "\n"
1489 "On most systems a file can be extended by giving a length\n"
1490 "greater than the current size, but this is not mandatory in the\n"
1491 "POSIX standard.")
1492 #define FUNC_NAME s_scm_truncate_file
1493 {
1494 int rv;
1495
1496 /* "object" can be a port, fdes or filename.
1497
1498 Negative "length" makes no sense, but it's left to truncate() or
1499 ftruncate() to give back an error for that (normally EINVAL).
1500 */
1501
1502 if (SCM_UNBNDP (length))
1503 {
1504 /* must supply length if object is a filename. */
1505 if (scm_is_string (object))
1506 SCM_MISC_ERROR("must supply length if OBJECT is a filename", SCM_EOL);
1507
1508 length = scm_seek (object, SCM_INUM0, scm_from_int (SEEK_CUR));
1509 }
1510
1511 object = SCM_COERCE_OUTPORT (object);
1512 if (scm_is_integer (object))
1513 {
1514 off_t_or_off64_t c_length = scm_to_off_t_or_off64_t (length);
1515 SCM_SYSCALL (rv = ftruncate_or_ftruncate64 (scm_to_int (object),
1516 c_length));
1517 }
1518 else if (SCM_OPOUTFPORTP (object))
1519 {
1520 /* go direct to fport code to allow 64-bit offsets */
1521 rv = scm_i_fport_truncate (object, length);
1522 }
1523 else if (SCM_OPOUTPORTP (object))
1524 {
1525 off_t c_length = scm_to_off_t (length);
1526 scm_t_port *pt = SCM_PTAB_ENTRY (object);
1527 scm_t_ptob_descriptor *ptob = scm_ptobs + SCM_PTOBNUM (object);
1528
1529 if (!ptob->truncate)
1530 SCM_MISC_ERROR ("port is not truncatable", SCM_EOL);
1531 if (pt->rw_active == SCM_PORT_READ)
1532 scm_end_input (object);
1533 else if (pt->rw_active == SCM_PORT_WRITE)
1534 ptob->flush (object);
1535
1536 ptob->truncate (object, c_length);
1537 rv = 0;
1538 }
1539 else
1540 {
1541 off_t_or_off64_t c_length = scm_to_off_t_or_off64_t (length);
1542 char *str = scm_to_locale_string (object);
1543 int eno;
1544 SCM_SYSCALL (rv = truncate_or_truncate64 (str, c_length));
1545 eno = errno;
1546 free (str);
1547 errno = eno;
1548 }
1549 if (rv == -1)
1550 SCM_SYSERROR;
1551 return SCM_UNSPECIFIED;
1552 }
1553 #undef FUNC_NAME
1554
1555 SCM_DEFINE (scm_port_line, "port-line", 1, 0, 0,
1556 (SCM port),
1557 "Return the current line number for @var{port}.\n"
1558 "\n"
1559 "The first line of a file is 0. But you might want to add 1\n"
1560 "when printing line numbers, since starting from 1 is\n"
1561 "traditional in error messages, and likely to be more natural to\n"
1562 "non-programmers.")
1563 #define FUNC_NAME s_scm_port_line
1564 {
1565 port = SCM_COERCE_OUTPORT (port);
1566 SCM_VALIDATE_OPENPORT (1, port);
1567 return scm_from_long (SCM_LINUM (port));
1568 }
1569 #undef FUNC_NAME
1570
1571 SCM_DEFINE (scm_set_port_line_x, "set-port-line!", 2, 0, 0,
1572 (SCM port, SCM line),
1573 "Set the current line number for @var{port} to @var{line}. The\n"
1574 "first line of a file is 0.")
1575 #define FUNC_NAME s_scm_set_port_line_x
1576 {
1577 port = SCM_COERCE_OUTPORT (port);
1578 SCM_VALIDATE_OPENPORT (1, port);
1579 SCM_PTAB_ENTRY (port)->line_number = scm_to_long (line);
1580 return SCM_UNSPECIFIED;
1581 }
1582 #undef FUNC_NAME
1583
1584 SCM_DEFINE (scm_port_column, "port-column", 1, 0, 0,
1585 (SCM port),
1586 "Return the current column number of @var{port}.\n"
1587 "If the number is\n"
1588 "unknown, the result is #f. Otherwise, the result is a 0-origin integer\n"
1589 "- i.e. the first character of the first line is line 0, column 0.\n"
1590 "(However, when you display a file position, for example in an error\n"
1591 "message, we recommend you add 1 to get 1-origin integers. This is\n"
1592 "because lines and column numbers traditionally start with 1, and that is\n"
1593 "what non-programmers will find most natural.)")
1594 #define FUNC_NAME s_scm_port_column
1595 {
1596 port = SCM_COERCE_OUTPORT (port);
1597 SCM_VALIDATE_OPENPORT (1, port);
1598 return scm_from_int (SCM_COL (port));
1599 }
1600 #undef FUNC_NAME
1601
1602 SCM_DEFINE (scm_set_port_column_x, "set-port-column!", 2, 0, 0,
1603 (SCM port, SCM column),
1604 "Set the current column of @var{port}. Before reading the first\n"
1605 "character on a line the column should be 0.")
1606 #define FUNC_NAME s_scm_set_port_column_x
1607 {
1608 port = SCM_COERCE_OUTPORT (port);
1609 SCM_VALIDATE_OPENPORT (1, port);
1610 SCM_PTAB_ENTRY (port)->column_number = scm_to_int (column);
1611 return SCM_UNSPECIFIED;
1612 }
1613 #undef FUNC_NAME
1614
1615 SCM_DEFINE (scm_port_filename, "port-filename", 1, 0, 0,
1616 (SCM port),
1617 "Return the filename associated with @var{port}. This function returns\n"
1618 "the strings \"standard input\", \"standard output\" and \"standard error\"\n"
1619 "when called on the current input, output and error ports respectively.")
1620 #define FUNC_NAME s_scm_port_filename
1621 {
1622 port = SCM_COERCE_OUTPORT (port);
1623 SCM_VALIDATE_OPENPORT (1, port);
1624 return SCM_FILENAME (port);
1625 }
1626 #undef FUNC_NAME
1627
1628 SCM_DEFINE (scm_set_port_filename_x, "set-port-filename!", 2, 0, 0,
1629 (SCM port, SCM filename),
1630 "Change the filename associated with @var{port}, using the current input\n"
1631 "port if none is specified. Note that this does not change the port's\n"
1632 "source of data, but only the value that is returned by\n"
1633 "@code{port-filename} and reported in diagnostic output.")
1634 #define FUNC_NAME s_scm_set_port_filename_x
1635 {
1636 port = SCM_COERCE_OUTPORT (port);
1637 SCM_VALIDATE_OPENPORT (1, port);
1638 /* We allow the user to set the filename to whatever he likes. */
1639 SCM_SET_FILENAME (port, filename);
1640 return SCM_UNSPECIFIED;
1641 }
1642 #undef FUNC_NAME
1643
1644 void
scm_print_port_mode(SCM exp,SCM port)1645 scm_print_port_mode (SCM exp, SCM port)
1646 {
1647 scm_puts (SCM_CLOSEDP (exp)
1648 ? "closed: "
1649 : (SCM_RDNG & SCM_CELL_WORD_0 (exp)
1650 ? (SCM_WRTNG & SCM_CELL_WORD_0 (exp)
1651 ? "input-output: "
1652 : "input: ")
1653 : (SCM_WRTNG & SCM_CELL_WORD_0 (exp)
1654 ? "output: "
1655 : "bogus: ")),
1656 port);
1657 }
1658
1659 int
scm_port_print(SCM exp,SCM port,scm_print_state * pstate SCM_UNUSED)1660 scm_port_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED)
1661 {
1662 char *type = SCM_PTOBNAME (SCM_PTOBNUM (exp));
1663 if (!type)
1664 type = "port";
1665 scm_puts ("#<", port);
1666 scm_print_port_mode (exp, port);
1667 scm_puts (type, port);
1668 scm_putc (' ', port);
1669 scm_uintprint (SCM_CELL_WORD_1 (exp), 16, port);
1670 scm_putc ('>', port);
1671 return 1;
1672 }
1673
1674 void
scm_ports_prehistory()1675 scm_ports_prehistory ()
1676 {
1677 scm_numptob = 0;
1678 scm_ptobs = (scm_t_ptob_descriptor *) scm_malloc (sizeof (scm_t_ptob_descriptor));
1679 }
1680
1681
1682
1683 /* Void ports. */
1684
1685 scm_t_bits scm_tc16_void_port = 0;
1686
fill_input_void_port(SCM port SCM_UNUSED)1687 static int fill_input_void_port (SCM port SCM_UNUSED)
1688 {
1689 return EOF;
1690 }
1691
1692 static void
write_void_port(SCM port SCM_UNUSED,const void * data SCM_UNUSED,size_t size SCM_UNUSED)1693 write_void_port (SCM port SCM_UNUSED,
1694 const void *data SCM_UNUSED,
1695 size_t size SCM_UNUSED)
1696 {
1697 }
1698
1699 static SCM
scm_i_void_port(long mode_bits)1700 scm_i_void_port (long mode_bits)
1701 {
1702 scm_i_scm_pthread_mutex_lock (&scm_i_port_table_mutex);
1703 {
1704 SCM answer = scm_new_port_table_entry (scm_tc16_void_port);
1705 scm_t_port * pt = SCM_PTAB_ENTRY(answer);
1706
1707 scm_port_non_buffer (pt);
1708
1709 SCM_SETSTREAM (answer, 0);
1710 SCM_SET_CELL_TYPE (answer, scm_tc16_void_port | mode_bits);
1711 scm_i_pthread_mutex_unlock (&scm_i_port_table_mutex);
1712 return answer;
1713 }
1714 }
1715
1716 SCM
scm_void_port(char * mode_str)1717 scm_void_port (char *mode_str)
1718 {
1719 return scm_i_void_port (scm_mode_bits (mode_str));
1720 }
1721
1722 SCM_DEFINE (scm_sys_make_void_port, "%make-void-port", 1, 0, 0,
1723 (SCM mode),
1724 "Create and return a new void port. A void port acts like\n"
1725 "@file{/dev/null}. The @var{mode} argument\n"
1726 "specifies the input/output modes for this port: see the\n"
1727 "documentation for @code{open-file} in @ref{File Ports}.")
1728 #define FUNC_NAME s_scm_sys_make_void_port
1729 {
1730 return scm_i_void_port (scm_i_mode_bits (mode));
1731 }
1732 #undef FUNC_NAME
1733
1734
1735 /* Initialization. */
1736
1737 void
scm_init_ports()1738 scm_init_ports ()
1739 {
1740 /* lseek() symbols. */
1741 scm_c_define ("SEEK_SET", scm_from_int (SEEK_SET));
1742 scm_c_define ("SEEK_CUR", scm_from_int (SEEK_CUR));
1743 scm_c_define ("SEEK_END", scm_from_int (SEEK_END));
1744
1745 scm_tc16_void_port = scm_make_port_type ("void", fill_input_void_port,
1746 write_void_port);
1747
1748 cur_inport_fluid = scm_permanent_object (scm_make_fluid ());
1749 cur_outport_fluid = scm_permanent_object (scm_make_fluid ());
1750 cur_errport_fluid = scm_permanent_object (scm_make_fluid ());
1751 cur_loadport_fluid = scm_permanent_object (scm_make_fluid ());
1752
1753 #include "libguile/ports.x"
1754 }
1755
1756 /*
1757 Local Variables:
1758 c-file-style: "gnu"
1759 End:
1760 */
1761