| 1 | /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2003, 2004 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 16 | */ |
| 17 | |
| 18 | |
| 19 | \f |
| 20 | /* Headers. */ |
| 21 | |
| 22 | #if HAVE_CONFIG_H |
| 23 | # include <config.h> |
| 24 | #endif |
| 25 | |
| 26 | #include <stdio.h> |
| 27 | #include <errno.h> |
| 28 | |
| 29 | #include "libguile/_scm.h" |
| 30 | #include "libguile/eval.h" |
| 31 | #include "libguile/objects.h" |
| 32 | #include "libguile/smob.h" |
| 33 | #include "libguile/chars.h" |
| 34 | #include "libguile/dynwind.h" |
| 35 | |
| 36 | #include "libguile/keywords.h" |
| 37 | #include "libguile/root.h" |
| 38 | #include "libguile/strings.h" |
| 39 | #include "libguile/mallocs.h" |
| 40 | #include "libguile/validate.h" |
| 41 | #include "libguile/ports.h" |
| 42 | |
| 43 | #ifdef HAVE_STRING_H |
| 44 | #include <string.h> |
| 45 | #endif |
| 46 | |
| 47 | #ifdef HAVE_MALLOC_H |
| 48 | #include <malloc.h> |
| 49 | #endif |
| 50 | |
| 51 | #ifdef HAVE_IO_H |
| 52 | #include <io.h> |
| 53 | #endif |
| 54 | |
| 55 | #ifdef HAVE_UNISTD_H |
| 56 | #include <unistd.h> |
| 57 | #endif |
| 58 | |
| 59 | #ifdef HAVE_SYS_IOCTL_H |
| 60 | #include <sys/ioctl.h> |
| 61 | #endif |
| 62 | |
| 63 | #ifdef __MINGW32__ |
| 64 | #include <fcntl.h> |
| 65 | #define ftruncate(fd, size) chsize (fd, size) |
| 66 | #endif |
| 67 | |
| 68 | \f |
| 69 | /* The port kind table --- a dynamically resized array of port types. */ |
| 70 | |
| 71 | |
| 72 | /* scm_ptobs scm_numptob |
| 73 | * implement a dynamicly resized array of ptob records. |
| 74 | * Indexes into this table are used when generating type |
| 75 | * tags for smobjects (if you know a tag you can get an index and conversely). |
| 76 | */ |
| 77 | scm_t_ptob_descriptor *scm_ptobs; |
| 78 | long scm_numptob; |
| 79 | |
| 80 | /* GC marker for a port with stream of SCM type. */ |
| 81 | SCM |
| 82 | scm_markstream (SCM ptr) |
| 83 | { |
| 84 | int openp; |
| 85 | openp = SCM_CELL_WORD_0 (ptr) & SCM_OPN; |
| 86 | if (openp) |
| 87 | return SCM_PACK (SCM_STREAM (ptr)); |
| 88 | else |
| 89 | return SCM_BOOL_F; |
| 90 | } |
| 91 | |
| 92 | /* |
| 93 | * We choose to use an interface similar to the smob interface with |
| 94 | * fill_input and write as standard fields, passed to the port |
| 95 | * type constructor, and optional fields set by setters. |
| 96 | */ |
| 97 | |
| 98 | static void |
| 99 | flush_port_default (SCM port SCM_UNUSED) |
| 100 | { |
| 101 | } |
| 102 | |
| 103 | static void |
| 104 | end_input_default (SCM port SCM_UNUSED, int offset SCM_UNUSED) |
| 105 | { |
| 106 | } |
| 107 | |
| 108 | static size_t |
| 109 | scm_port_free0 (SCM port) |
| 110 | { |
| 111 | return 0; |
| 112 | } |
| 113 | |
| 114 | scm_t_bits |
| 115 | scm_make_port_type (char *name, |
| 116 | int (*fill_input) (SCM port), |
| 117 | void (*write) (SCM port, const void *data, size_t size)) |
| 118 | { |
| 119 | char *tmp; |
| 120 | if (255 <= scm_numptob) |
| 121 | goto ptoberr; |
| 122 | SCM_DEFER_INTS; |
| 123 | SCM_SYSCALL (tmp = (char *) realloc ((char *) scm_ptobs, |
| 124 | (1 + scm_numptob) |
| 125 | * sizeof (scm_t_ptob_descriptor))); |
| 126 | if (tmp) |
| 127 | { |
| 128 | scm_ptobs = (scm_t_ptob_descriptor *) tmp; |
| 129 | |
| 130 | scm_ptobs[scm_numptob].name = name; |
| 131 | scm_ptobs[scm_numptob].mark = 0; |
| 132 | scm_ptobs[scm_numptob].free = scm_port_free0; |
| 133 | scm_ptobs[scm_numptob].print = scm_port_print; |
| 134 | scm_ptobs[scm_numptob].equalp = 0; |
| 135 | scm_ptobs[scm_numptob].close = 0; |
| 136 | |
| 137 | scm_ptobs[scm_numptob].write = write; |
| 138 | scm_ptobs[scm_numptob].flush = flush_port_default; |
| 139 | |
| 140 | scm_ptobs[scm_numptob].end_input = end_input_default; |
| 141 | scm_ptobs[scm_numptob].fill_input = fill_input; |
| 142 | scm_ptobs[scm_numptob].input_waiting = 0; |
| 143 | |
| 144 | scm_ptobs[scm_numptob].seek = 0; |
| 145 | scm_ptobs[scm_numptob].truncate = 0; |
| 146 | |
| 147 | scm_numptob++; |
| 148 | } |
| 149 | SCM_ALLOW_INTS; |
| 150 | if (!tmp) |
| 151 | { |
| 152 | ptoberr: |
| 153 | scm_memory_error ("scm_make_port_type"); |
| 154 | } |
| 155 | /* Make a class object if Goops is present */ |
| 156 | if (scm_port_class) |
| 157 | scm_make_port_classes (scm_numptob - 1, SCM_PTOBNAME (scm_numptob - 1)); |
| 158 | return scm_tc7_port + (scm_numptob - 1) * 256; |
| 159 | } |
| 160 | |
| 161 | void |
| 162 | scm_set_port_mark (long tc, SCM (*mark) (SCM)) |
| 163 | { |
| 164 | scm_ptobs[SCM_TC2PTOBNUM (tc)].mark = mark; |
| 165 | } |
| 166 | |
| 167 | void |
| 168 | scm_set_port_free (long tc, size_t (*free) (SCM)) |
| 169 | { |
| 170 | scm_ptobs[SCM_TC2PTOBNUM (tc)].free = free; |
| 171 | } |
| 172 | |
| 173 | void |
| 174 | scm_set_port_print (long tc, int (*print) (SCM exp, SCM port, |
| 175 | scm_print_state *pstate)) |
| 176 | { |
| 177 | scm_ptobs[SCM_TC2PTOBNUM (tc)].print = print; |
| 178 | } |
| 179 | |
| 180 | void |
| 181 | scm_set_port_equalp (long tc, SCM (*equalp) (SCM, SCM)) |
| 182 | { |
| 183 | scm_ptobs[SCM_TC2PTOBNUM (tc)].equalp = equalp; |
| 184 | } |
| 185 | |
| 186 | void |
| 187 | scm_set_port_flush (long tc, void (*flush) (SCM port)) |
| 188 | { |
| 189 | scm_ptobs[SCM_TC2PTOBNUM (tc)].flush = flush; |
| 190 | } |
| 191 | |
| 192 | void |
| 193 | scm_set_port_end_input (long tc, void (*end_input) (SCM port, int offset)) |
| 194 | { |
| 195 | scm_ptobs[SCM_TC2PTOBNUM (tc)].end_input = end_input; |
| 196 | } |
| 197 | |
| 198 | void |
| 199 | scm_set_port_close (long tc, int (*close) (SCM)) |
| 200 | { |
| 201 | scm_ptobs[SCM_TC2PTOBNUM (tc)].close = close; |
| 202 | } |
| 203 | |
| 204 | void |
| 205 | scm_set_port_seek (long tc, off_t (*seek) (SCM port, |
| 206 | off_t OFFSET, |
| 207 | int WHENCE)) |
| 208 | { |
| 209 | scm_ptobs[SCM_TC2PTOBNUM (tc)].seek = seek; |
| 210 | } |
| 211 | |
| 212 | void |
| 213 | scm_set_port_truncate (long tc, void (*truncate) (SCM port, off_t length)) |
| 214 | { |
| 215 | scm_ptobs[SCM_TC2PTOBNUM (tc)].truncate = truncate; |
| 216 | } |
| 217 | |
| 218 | void |
| 219 | scm_set_port_input_waiting (long tc, int (*input_waiting) (SCM)) |
| 220 | { |
| 221 | scm_ptobs[SCM_TC2PTOBNUM (tc)].input_waiting = input_waiting; |
| 222 | } |
| 223 | |
| 224 | \f |
| 225 | |
| 226 | SCM_DEFINE (scm_char_ready_p, "char-ready?", 0, 1, 0, |
| 227 | (SCM port), |
| 228 | "Return @code{#t} if a character is ready on input @var{port}\n" |
| 229 | "and return @code{#f} otherwise. If @code{char-ready?} returns\n" |
| 230 | "@code{#t} then the next @code{read-char} operation on\n" |
| 231 | "@var{port} is guaranteed not to hang. If @var{port} is a file\n" |
| 232 | "port at end of file then @code{char-ready?} returns @code{#t}.\n" |
| 233 | "\n" |
| 234 | "@code{char-ready?} exists to make it possible for a\n" |
| 235 | "program to accept characters from interactive ports without\n" |
| 236 | "getting stuck waiting for input. Any input editors associated\n" |
| 237 | "with such ports must make sure that characters whose existence\n" |
| 238 | "has been asserted by @code{char-ready?} cannot be rubbed out.\n" |
| 239 | "If @code{char-ready?} were to return @code{#f} at end of file,\n" |
| 240 | "a port at end of file would be indistinguishable from an\n" |
| 241 | "interactive port that has no ready characters.") |
| 242 | #define FUNC_NAME s_scm_char_ready_p |
| 243 | { |
| 244 | scm_t_port *pt; |
| 245 | |
| 246 | if (SCM_UNBNDP (port)) |
| 247 | port = scm_cur_inp; |
| 248 | else |
| 249 | SCM_VALIDATE_OPINPORT (1, port); |
| 250 | |
| 251 | pt = SCM_PTAB_ENTRY (port); |
| 252 | |
| 253 | /* if the current read buffer is filled, or the |
| 254 | last pushed-back char has been read and the saved buffer is |
| 255 | filled, result is true. */ |
| 256 | if (pt->read_pos < pt->read_end |
| 257 | || (pt->read_buf == pt->putback_buf |
| 258 | && pt->saved_read_pos < pt->saved_read_end)) |
| 259 | return SCM_BOOL_T; |
| 260 | else |
| 261 | { |
| 262 | scm_t_ptob_descriptor *ptob = &scm_ptobs[SCM_PTOBNUM (port)]; |
| 263 | |
| 264 | if (ptob->input_waiting) |
| 265 | return scm_from_bool(ptob->input_waiting (port)); |
| 266 | else |
| 267 | return SCM_BOOL_T; |
| 268 | } |
| 269 | } |
| 270 | #undef FUNC_NAME |
| 271 | |
| 272 | /* move up to read_len chars from port's putback and/or read buffers |
| 273 | into memory starting at dest. returns the number of chars moved. */ |
| 274 | size_t scm_take_from_input_buffers (SCM port, char *dest, size_t read_len) |
| 275 | { |
| 276 | scm_t_port *pt = SCM_PTAB_ENTRY (port); |
| 277 | size_t chars_read = 0; |
| 278 | size_t from_buf = min (pt->read_end - pt->read_pos, read_len); |
| 279 | |
| 280 | if (from_buf > 0) |
| 281 | { |
| 282 | memcpy (dest, pt->read_pos, from_buf); |
| 283 | pt->read_pos += from_buf; |
| 284 | chars_read += from_buf; |
| 285 | read_len -= from_buf; |
| 286 | dest += from_buf; |
| 287 | } |
| 288 | |
| 289 | /* if putback was active, try the real input buffer too. */ |
| 290 | if (pt->read_buf == pt->putback_buf) |
| 291 | { |
| 292 | from_buf = min (pt->saved_read_end - pt->saved_read_pos, read_len); |
| 293 | if (from_buf > 0) |
| 294 | { |
| 295 | memcpy (dest, pt->saved_read_pos, from_buf); |
| 296 | pt->saved_read_pos += from_buf; |
| 297 | chars_read += from_buf; |
| 298 | } |
| 299 | } |
| 300 | return chars_read; |
| 301 | } |
| 302 | |
| 303 | /* Clear a port's read buffers, returning the contents. */ |
| 304 | SCM_DEFINE (scm_drain_input, "drain-input", 1, 0, 0, |
| 305 | (SCM port), |
| 306 | "This procedure clears a port's input buffers, similar\n" |
| 307 | "to the way that force-output clears the output buffer. The\n" |
| 308 | "contents of the buffers are returned as a single string, e.g.,\n" |
| 309 | "\n" |
| 310 | "@lisp\n" |
| 311 | "(define p (open-input-file ...))\n" |
| 312 | "(drain-input p) => empty string, nothing buffered yet.\n" |
| 313 | "(unread-char (read-char p) p)\n" |
| 314 | "(drain-input p) => initial chars from p, up to the buffer size.\n" |
| 315 | "@end lisp\n\n" |
| 316 | "Draining the buffers may be useful for cleanly finishing\n" |
| 317 | "buffered I/O so that the file descriptor can be used directly\n" |
| 318 | "for further input.") |
| 319 | #define FUNC_NAME s_scm_drain_input |
| 320 | { |
| 321 | SCM result; |
| 322 | scm_t_port *pt; |
| 323 | long count; |
| 324 | |
| 325 | SCM_VALIDATE_OPINPORT (1, port); |
| 326 | pt = SCM_PTAB_ENTRY (port); |
| 327 | |
| 328 | count = pt->read_end - pt->read_pos; |
| 329 | if (pt->read_buf == pt->putback_buf) |
| 330 | count += pt->saved_read_end - pt->saved_read_pos; |
| 331 | |
| 332 | result = scm_allocate_string (count); |
| 333 | scm_take_from_input_buffers (port, SCM_I_STRING_CHARS (result), count); |
| 334 | |
| 335 | return result; |
| 336 | } |
| 337 | #undef FUNC_NAME |
| 338 | |
| 339 | \f |
| 340 | /* Standard ports --- current input, output, error, and more(!). */ |
| 341 | |
| 342 | SCM_DEFINE (scm_current_input_port, "current-input-port", 0, 0, 0, |
| 343 | (), |
| 344 | "Return the current input port. This is the default port used\n" |
| 345 | "by many input procedures. Initially, @code{current-input-port}\n" |
| 346 | "returns the @dfn{standard input} in Unix and C terminology.") |
| 347 | #define FUNC_NAME s_scm_current_input_port |
| 348 | { |
| 349 | return scm_cur_inp; |
| 350 | } |
| 351 | #undef FUNC_NAME |
| 352 | |
| 353 | SCM_DEFINE (scm_current_output_port, "current-output-port", 0, 0, 0, |
| 354 | (), |
| 355 | "Return the current output port. This is the default port used\n" |
| 356 | "by many output procedures. Initially,\n" |
| 357 | "@code{current-output-port} returns the @dfn{standard output} in\n" |
| 358 | "Unix and C terminology.") |
| 359 | #define FUNC_NAME s_scm_current_output_port |
| 360 | { |
| 361 | return scm_cur_outp; |
| 362 | } |
| 363 | #undef FUNC_NAME |
| 364 | |
| 365 | SCM_DEFINE (scm_current_error_port, "current-error-port", 0, 0, 0, |
| 366 | (), |
| 367 | "Return the port to which errors and warnings should be sent (the\n" |
| 368 | "@dfn{standard error} in Unix and C terminology).") |
| 369 | #define FUNC_NAME s_scm_current_error_port |
| 370 | { |
| 371 | return scm_cur_errp; |
| 372 | } |
| 373 | #undef FUNC_NAME |
| 374 | |
| 375 | SCM_DEFINE (scm_current_load_port, "current-load-port", 0, 0, 0, |
| 376 | (), |
| 377 | "Return the current-load-port.\n" |
| 378 | "The load port is used internally by @code{primitive-load}.") |
| 379 | #define FUNC_NAME s_scm_current_load_port |
| 380 | { |
| 381 | return scm_cur_loadp; |
| 382 | } |
| 383 | #undef FUNC_NAME |
| 384 | |
| 385 | SCM_DEFINE (scm_set_current_input_port, "set-current-input-port", 1, 0, 0, |
| 386 | (SCM port), |
| 387 | "@deffnx {Scheme Procedure} set-current-output-port port\n" |
| 388 | "@deffnx {Scheme Procedure} set-current-error-port port\n" |
| 389 | "Change the ports returned by @code{current-input-port},\n" |
| 390 | "@code{current-output-port} and @code{current-error-port}, respectively,\n" |
| 391 | "so that they use the supplied @var{port} for input or output.") |
| 392 | #define FUNC_NAME s_scm_set_current_input_port |
| 393 | { |
| 394 | SCM oinp = scm_cur_inp; |
| 395 | SCM_VALIDATE_OPINPORT (1, port); |
| 396 | scm_cur_inp = port; |
| 397 | return oinp; |
| 398 | } |
| 399 | #undef FUNC_NAME |
| 400 | |
| 401 | |
| 402 | SCM_DEFINE (scm_set_current_output_port, "set-current-output-port", 1, 0, 0, |
| 403 | (SCM port), |
| 404 | "Set the current default output port to @var{port}.") |
| 405 | #define FUNC_NAME s_scm_set_current_output_port |
| 406 | { |
| 407 | SCM ooutp = scm_cur_outp; |
| 408 | port = SCM_COERCE_OUTPORT (port); |
| 409 | SCM_VALIDATE_OPOUTPORT (1, port); |
| 410 | scm_cur_outp = port; |
| 411 | return ooutp; |
| 412 | } |
| 413 | #undef FUNC_NAME |
| 414 | |
| 415 | |
| 416 | SCM_DEFINE (scm_set_current_error_port, "set-current-error-port", 1, 0, 0, |
| 417 | (SCM port), |
| 418 | "Set the current default error port to @var{port}.") |
| 419 | #define FUNC_NAME s_scm_set_current_error_port |
| 420 | { |
| 421 | SCM oerrp = scm_cur_errp; |
| 422 | port = SCM_COERCE_OUTPORT (port); |
| 423 | SCM_VALIDATE_OPOUTPORT (1, port); |
| 424 | scm_cur_errp = port; |
| 425 | return oerrp; |
| 426 | } |
| 427 | #undef FUNC_NAME |
| 428 | |
| 429 | typedef struct { |
| 430 | SCM value; |
| 431 | SCM (*getter) (void); |
| 432 | SCM (*setter) (SCM); |
| 433 | } swap_data; |
| 434 | |
| 435 | static void |
| 436 | swap_port (SCM scm_data) |
| 437 | { |
| 438 | swap_data *d = (swap_data *)SCM_MALLOCDATA (scm_data); |
| 439 | SCM t; |
| 440 | |
| 441 | t = d->getter (); |
| 442 | d->setter (d->value); |
| 443 | d->value = t; |
| 444 | } |
| 445 | |
| 446 | static void |
| 447 | scm_frame_current_foo_port (SCM port, |
| 448 | SCM (*getter) (void), SCM (*setter) (SCM)) |
| 449 | { |
| 450 | SCM scm_data = scm_malloc_obj (sizeof (swap_data)); |
| 451 | swap_data *data = (swap_data *)SCM_MALLOCDATA (scm_data); |
| 452 | data->value = port; |
| 453 | data->getter = getter; |
| 454 | data->setter = setter; |
| 455 | |
| 456 | scm_frame_rewind_handler_with_scm (swap_port, scm_data, |
| 457 | SCM_F_WIND_EXPLICITLY); |
| 458 | scm_frame_unwind_handler_with_scm (swap_port, scm_data, |
| 459 | SCM_F_WIND_EXPLICITLY); |
| 460 | } |
| 461 | |
| 462 | void |
| 463 | scm_frame_current_input_port (SCM port) |
| 464 | { |
| 465 | scm_frame_current_foo_port (port, |
| 466 | scm_current_input_port, |
| 467 | scm_set_current_input_port); |
| 468 | } |
| 469 | |
| 470 | void |
| 471 | scm_frame_current_output_port (SCM port) |
| 472 | { |
| 473 | scm_frame_current_foo_port (port, |
| 474 | scm_current_output_port, |
| 475 | scm_set_current_output_port); |
| 476 | } |
| 477 | |
| 478 | void |
| 479 | scm_frame_current_error_port (SCM port) |
| 480 | { |
| 481 | scm_frame_current_foo_port (port, |
| 482 | scm_current_error_port, |
| 483 | scm_set_current_error_port); |
| 484 | } |
| 485 | |
| 486 | \f |
| 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_GLOBAL_MUTEX (scm_i_port_table_mutex); |
| 495 | |
| 496 | /* This function is not and should not be thread safe. */ |
| 497 | |
| 498 | SCM |
| 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 * |
| 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 |
| 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 |
| 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 | \f |
| 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 |
| 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 | \f |
| 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 | long |
| 672 | scm_mode_bits (char *modes) |
| 673 | { |
| 674 | return (SCM_OPN |
| 675 | | (strchr (modes, 'r') || strchr (modes, '+') ? SCM_RDNG : 0) |
| 676 | | ( strchr (modes, 'w') |
| 677 | || strchr (modes, 'a') |
| 678 | || strchr (modes, '+') ? SCM_WRTNG : 0) |
| 679 | | (strchr (modes, '0') ? SCM_BUF0 : 0) |
| 680 | | (strchr (modes, 'l') ? SCM_BUFLINE : 0)); |
| 681 | } |
| 682 | |
| 683 | long |
| 684 | scm_i_mode_bits (SCM modes) |
| 685 | { |
| 686 | long bits; |
| 687 | |
| 688 | if (!scm_is_string (modes)) |
| 689 | scm_wrong_type_arg_msg (NULL, 0, modes, "string"); |
| 690 | |
| 691 | bits = scm_mode_bits (SCM_I_STRING_CHARS (modes)); |
| 692 | scm_remember_upto_here_1 (modes); |
| 693 | return bits; |
| 694 | } |
| 695 | |
| 696 | /* Return the mode flags from an open port. |
| 697 | * Some modes such as "append" are only used when opening |
| 698 | * a file and are not returned here. */ |
| 699 | |
| 700 | SCM_DEFINE (scm_port_mode, "port-mode", 1, 0, 0, |
| 701 | (SCM port), |
| 702 | "Return the port modes associated with the open port @var{port}.\n" |
| 703 | "These will not necessarily be identical to the modes used when\n" |
| 704 | "the port was opened, since modes such as \"append\" which are\n" |
| 705 | "used only during port creation are not retained.") |
| 706 | #define FUNC_NAME s_scm_port_mode |
| 707 | { |
| 708 | char modes[4]; |
| 709 | modes[0] = '\0'; |
| 710 | |
| 711 | port = SCM_COERCE_OUTPORT (port); |
| 712 | SCM_VALIDATE_OPPORT (1, port); |
| 713 | if (SCM_CELL_WORD_0 (port) & SCM_RDNG) { |
| 714 | if (SCM_CELL_WORD_0 (port) & SCM_WRTNG) |
| 715 | strcpy (modes, "r+"); |
| 716 | else |
| 717 | strcpy (modes, "r"); |
| 718 | } |
| 719 | else if (SCM_CELL_WORD_0 (port) & SCM_WRTNG) |
| 720 | strcpy (modes, "w"); |
| 721 | if (SCM_CELL_WORD_0 (port) & SCM_BUF0) |
| 722 | strcat (modes, "0"); |
| 723 | return scm_mem2string (modes, strlen (modes)); |
| 724 | } |
| 725 | #undef FUNC_NAME |
| 726 | |
| 727 | |
| 728 | \f |
| 729 | /* Closing ports. */ |
| 730 | |
| 731 | /* scm_close_port |
| 732 | * Call the close operation on a port object. |
| 733 | * see also scm_close. |
| 734 | */ |
| 735 | SCM_DEFINE (scm_close_port, "close-port", 1, 0, 0, |
| 736 | (SCM port), |
| 737 | "Close the specified port object. Return @code{#t} if it\n" |
| 738 | "successfully closes a port or @code{#f} if it was already\n" |
| 739 | "closed. An exception may be raised if an error occurs, for\n" |
| 740 | "example when flushing buffered output. See also @ref{Ports and\n" |
| 741 | "File Descriptors, close}, for a procedure which can close file\n" |
| 742 | "descriptors.") |
| 743 | #define FUNC_NAME s_scm_close_port |
| 744 | { |
| 745 | size_t i; |
| 746 | int rv; |
| 747 | |
| 748 | port = SCM_COERCE_OUTPORT (port); |
| 749 | |
| 750 | SCM_VALIDATE_PORT (1, port); |
| 751 | if (SCM_CLOSEDP (port)) |
| 752 | return SCM_BOOL_F; |
| 753 | i = SCM_PTOBNUM (port); |
| 754 | if (scm_ptobs[i].close) |
| 755 | rv = (scm_ptobs[i].close) (port); |
| 756 | else |
| 757 | rv = 0; |
| 758 | scm_mutex_lock (&scm_i_port_table_mutex); |
| 759 | scm_remove_from_port_table (port); |
| 760 | scm_mutex_unlock (&scm_i_port_table_mutex); |
| 761 | SCM_CLR_PORT_OPEN_FLAG (port); |
| 762 | return scm_from_bool (rv >= 0); |
| 763 | } |
| 764 | #undef FUNC_NAME |
| 765 | |
| 766 | SCM_DEFINE (scm_close_input_port, "close-input-port", 1, 0, 0, |
| 767 | (SCM port), |
| 768 | "Close the specified input port object. The routine has no effect if\n" |
| 769 | "the file has already been closed. An exception may be raised if an\n" |
| 770 | "error occurs. The value returned is unspecified.\n\n" |
| 771 | "See also @ref{Ports and File Descriptors, close}, for a procedure\n" |
| 772 | "which can close file descriptors.") |
| 773 | #define FUNC_NAME s_scm_close_input_port |
| 774 | { |
| 775 | SCM_VALIDATE_INPUT_PORT (1, port); |
| 776 | scm_close_port (port); |
| 777 | return SCM_UNSPECIFIED; |
| 778 | } |
| 779 | #undef FUNC_NAME |
| 780 | |
| 781 | SCM_DEFINE (scm_close_output_port, "close-output-port", 1, 0, 0, |
| 782 | (SCM port), |
| 783 | "Close the specified output port object. The routine has no effect if\n" |
| 784 | "the file has already been closed. An exception may be raised if an\n" |
| 785 | "error occurs. The value returned is unspecified.\n\n" |
| 786 | "See also @ref{Ports and File Descriptors, close}, for a procedure\n" |
| 787 | "which can close file descriptors.") |
| 788 | #define FUNC_NAME s_scm_close_output_port |
| 789 | { |
| 790 | port = SCM_COERCE_OUTPORT (port); |
| 791 | SCM_VALIDATE_OUTPUT_PORT (1, port); |
| 792 | scm_close_port (port); |
| 793 | return SCM_UNSPECIFIED; |
| 794 | } |
| 795 | #undef FUNC_NAME |
| 796 | |
| 797 | void |
| 798 | scm_c_port_for_each (void (*proc)(void *data, SCM p), void *data) |
| 799 | { |
| 800 | long i; |
| 801 | SCM ports; |
| 802 | |
| 803 | /* Even without pre-emptive multithreading, running arbitrary code |
| 804 | while scanning the port table is unsafe because the port table |
| 805 | can change arbitrarily (from a GC, for example). So we build a |
| 806 | list in advance while blocking the GC. -mvo */ |
| 807 | |
| 808 | scm_mutex_lock (&scm_i_port_table_mutex); |
| 809 | scm_block_gc++; |
| 810 | ports = SCM_EOL; |
| 811 | for (i = 0; i < scm_i_port_table_size; i++) |
| 812 | ports = scm_cons (scm_i_port_table[i]->port, ports); |
| 813 | scm_block_gc--; |
| 814 | scm_mutex_unlock (&scm_i_port_table_mutex); |
| 815 | |
| 816 | while (ports != SCM_EOL) |
| 817 | { |
| 818 | proc (data, SCM_CAR (ports)); |
| 819 | ports = SCM_CDR (ports); |
| 820 | } |
| 821 | } |
| 822 | |
| 823 | SCM_DEFINE (scm_port_for_each, "port-for-each", 1, 0, 0, |
| 824 | (SCM proc), |
| 825 | "Apply @var{proc} to each port in the Guile port table\n" |
| 826 | "in turn. The return value is unspecified. More specifically,\n" |
| 827 | "@var{proc} is applied exactly once to every port that exists\n" |
| 828 | "in the system at the time @var{port-for-each} is invoked.\n" |
| 829 | "Changes to the port table while @var{port-for-each} is running\n" |
| 830 | "have no effect as far as @var{port-for-each} is concerned.") |
| 831 | #define FUNC_NAME s_scm_port_for_each |
| 832 | { |
| 833 | SCM_VALIDATE_PROC (1, proc); |
| 834 | |
| 835 | scm_c_port_for_each ((void (*)(void*,SCM))scm_call_1, proc); |
| 836 | return SCM_UNSPECIFIED; |
| 837 | } |
| 838 | #undef FUNC_NAME |
| 839 | |
| 840 | |
| 841 | \f |
| 842 | /* Utter miscellany. Gosh, we should clean this up some time. */ |
| 843 | |
| 844 | SCM_DEFINE (scm_input_port_p, "input-port?", 1, 0, 0, |
| 845 | (SCM x), |
| 846 | "Return @code{#t} if @var{x} is an input port, otherwise return\n" |
| 847 | "@code{#f}. Any object satisfying this predicate also satisfies\n" |
| 848 | "@code{port?}.") |
| 849 | #define FUNC_NAME s_scm_input_port_p |
| 850 | { |
| 851 | return scm_from_bool (SCM_INPUT_PORT_P (x)); |
| 852 | } |
| 853 | #undef FUNC_NAME |
| 854 | |
| 855 | SCM_DEFINE (scm_output_port_p, "output-port?", 1, 0, 0, |
| 856 | (SCM x), |
| 857 | "Return @code{#t} if @var{x} is an output port, otherwise return\n" |
| 858 | "@code{#f}. Any object satisfying this predicate also satisfies\n" |
| 859 | "@code{port?}.") |
| 860 | #define FUNC_NAME s_scm_output_port_p |
| 861 | { |
| 862 | x = SCM_COERCE_OUTPORT (x); |
| 863 | return scm_from_bool (SCM_OUTPUT_PORT_P (x)); |
| 864 | } |
| 865 | #undef FUNC_NAME |
| 866 | |
| 867 | SCM_DEFINE (scm_port_p, "port?", 1, 0, 0, |
| 868 | (SCM x), |
| 869 | "Return a boolean indicating whether @var{x} is a port.\n" |
| 870 | "Equivalent to @code{(or (input-port? @var{x}) (output-port?\n" |
| 871 | "@var{x}))}.") |
| 872 | #define FUNC_NAME s_scm_port_p |
| 873 | { |
| 874 | return scm_from_bool (SCM_PORTP (x)); |
| 875 | } |
| 876 | #undef FUNC_NAME |
| 877 | |
| 878 | SCM_DEFINE (scm_port_closed_p, "port-closed?", 1, 0, 0, |
| 879 | (SCM port), |
| 880 | "Return @code{#t} if @var{port} is closed or @code{#f} if it is\n" |
| 881 | "open.") |
| 882 | #define FUNC_NAME s_scm_port_closed_p |
| 883 | { |
| 884 | SCM_VALIDATE_PORT (1, port); |
| 885 | return scm_from_bool (!SCM_OPPORTP (port)); |
| 886 | } |
| 887 | #undef FUNC_NAME |
| 888 | |
| 889 | SCM_DEFINE (scm_eof_object_p, "eof-object?", 1, 0, 0, |
| 890 | (SCM x), |
| 891 | "Return @code{#t} if @var{x} is an end-of-file object; otherwise\n" |
| 892 | "return @code{#f}.") |
| 893 | #define FUNC_NAME s_scm_eof_object_p |
| 894 | { |
| 895 | return scm_from_bool(SCM_EOF_OBJECT_P (x)); |
| 896 | } |
| 897 | #undef FUNC_NAME |
| 898 | |
| 899 | SCM_DEFINE (scm_force_output, "force-output", 0, 1, 0, |
| 900 | (SCM port), |
| 901 | "Flush the specified output port, or the current output port if @var{port}\n" |
| 902 | "is omitted. The current output buffer contents are passed to the\n" |
| 903 | "underlying port implementation (e.g., in the case of fports, the\n" |
| 904 | "data will be written to the file and the output buffer will be cleared.)\n" |
| 905 | "It has no effect on an unbuffered port.\n\n" |
| 906 | "The return value is unspecified.") |
| 907 | #define FUNC_NAME s_scm_force_output |
| 908 | { |
| 909 | if (SCM_UNBNDP (port)) |
| 910 | port = scm_cur_outp; |
| 911 | else |
| 912 | { |
| 913 | port = SCM_COERCE_OUTPORT (port); |
| 914 | SCM_VALIDATE_OPOUTPORT (1, port); |
| 915 | } |
| 916 | scm_flush (port); |
| 917 | return SCM_UNSPECIFIED; |
| 918 | } |
| 919 | #undef FUNC_NAME |
| 920 | |
| 921 | SCM_DEFINE (scm_flush_all_ports, "flush-all-ports", 0, 0, 0, |
| 922 | (), |
| 923 | "Equivalent to calling @code{force-output} on\n" |
| 924 | "all open output ports. The return value is unspecified.") |
| 925 | #define FUNC_NAME s_scm_flush_all_ports |
| 926 | { |
| 927 | size_t i; |
| 928 | |
| 929 | scm_mutex_lock (&scm_i_port_table_mutex); |
| 930 | for (i = 0; i < scm_i_port_table_size; i++) |
| 931 | { |
| 932 | if (SCM_OPOUTPORTP (scm_i_port_table[i]->port)) |
| 933 | scm_flush (scm_i_port_table[i]->port); |
| 934 | } |
| 935 | scm_mutex_unlock (&scm_i_port_table_mutex); |
| 936 | return SCM_UNSPECIFIED; |
| 937 | } |
| 938 | #undef FUNC_NAME |
| 939 | |
| 940 | SCM_DEFINE (scm_read_char, "read-char", 0, 1, 0, |
| 941 | (SCM port), |
| 942 | "Return the next character available from @var{port}, updating\n" |
| 943 | "@var{port} to point to the following character. If no more\n" |
| 944 | "characters are available, the end-of-file object is returned.") |
| 945 | #define FUNC_NAME s_scm_read_char |
| 946 | { |
| 947 | int c; |
| 948 | if (SCM_UNBNDP (port)) |
| 949 | port = scm_cur_inp; |
| 950 | SCM_VALIDATE_OPINPORT (1, port); |
| 951 | c = scm_getc (port); |
| 952 | if (EOF == c) |
| 953 | return SCM_EOF_VAL; |
| 954 | return SCM_MAKE_CHAR (c); |
| 955 | } |
| 956 | #undef FUNC_NAME |
| 957 | |
| 958 | /* this should only be called when the read buffer is empty. it |
| 959 | tries to refill the read buffer. it returns the first char from |
| 960 | the port, which is either EOF or *(pt->read_pos). */ |
| 961 | int |
| 962 | scm_fill_input (SCM port) |
| 963 | { |
| 964 | scm_t_port *pt = SCM_PTAB_ENTRY (port); |
| 965 | |
| 966 | if (pt->read_buf == pt->putback_buf) |
| 967 | { |
| 968 | /* finished reading put-back chars. */ |
| 969 | pt->read_buf = pt->saved_read_buf; |
| 970 | pt->read_pos = pt->saved_read_pos; |
| 971 | pt->read_end = pt->saved_read_end; |
| 972 | pt->read_buf_size = pt->saved_read_buf_size; |
| 973 | if (pt->read_pos < pt->read_end) |
| 974 | return *(pt->read_pos); |
| 975 | } |
| 976 | return scm_ptobs[SCM_PTOBNUM (port)].fill_input (port); |
| 977 | } |
| 978 | |
| 979 | int |
| 980 | scm_getc (SCM port) |
| 981 | { |
| 982 | int c; |
| 983 | scm_t_port *pt = SCM_PTAB_ENTRY (port); |
| 984 | |
| 985 | if (pt->rw_active == SCM_PORT_WRITE) |
| 986 | /* may be marginally faster than calling scm_flush. */ |
| 987 | scm_ptobs[SCM_PTOBNUM (port)].flush (port); |
| 988 | |
| 989 | if (pt->rw_random) |
| 990 | pt->rw_active = SCM_PORT_READ; |
| 991 | |
| 992 | if (pt->read_pos >= pt->read_end) |
| 993 | { |
| 994 | if (scm_fill_input (port) == EOF) |
| 995 | return EOF; |
| 996 | } |
| 997 | |
| 998 | c = *(pt->read_pos++); |
| 999 | |
| 1000 | switch (c) |
| 1001 | { |
| 1002 | case '\n': |
| 1003 | SCM_INCLINE (port); |
| 1004 | break; |
| 1005 | case '\t': |
| 1006 | SCM_TABCOL (port); |
| 1007 | break; |
| 1008 | default: |
| 1009 | SCM_INCCOL (port); |
| 1010 | break; |
| 1011 | } |
| 1012 | |
| 1013 | return c; |
| 1014 | } |
| 1015 | |
| 1016 | void |
| 1017 | scm_putc (char c, SCM port) |
| 1018 | { |
| 1019 | scm_lfwrite (&c, 1, port); |
| 1020 | } |
| 1021 | |
| 1022 | void |
| 1023 | scm_puts (const char *s, SCM port) |
| 1024 | { |
| 1025 | scm_lfwrite (s, strlen (s), port); |
| 1026 | } |
| 1027 | |
| 1028 | /* scm_lfwrite |
| 1029 | * |
| 1030 | * This function differs from scm_c_write; it updates port line and |
| 1031 | * column. */ |
| 1032 | |
| 1033 | void |
| 1034 | scm_lfwrite (const char *ptr, size_t size, SCM port) |
| 1035 | { |
| 1036 | scm_t_port *pt = SCM_PTAB_ENTRY (port); |
| 1037 | scm_t_ptob_descriptor *ptob = &scm_ptobs[SCM_PTOBNUM (port)]; |
| 1038 | |
| 1039 | if (pt->rw_active == SCM_PORT_READ) |
| 1040 | scm_end_input (port); |
| 1041 | |
| 1042 | ptob->write (port, ptr, size); |
| 1043 | |
| 1044 | for (; size; ptr++, size--) { |
| 1045 | if (*ptr == '\n') { |
| 1046 | SCM_INCLINE(port); |
| 1047 | } |
| 1048 | else if (*ptr == '\t') { |
| 1049 | SCM_TABCOL(port); |
| 1050 | } |
| 1051 | else { |
| 1052 | SCM_INCCOL(port); |
| 1053 | } |
| 1054 | } |
| 1055 | |
| 1056 | if (pt->rw_random) |
| 1057 | pt->rw_active = SCM_PORT_WRITE; |
| 1058 | } |
| 1059 | |
| 1060 | /* scm_c_read |
| 1061 | * |
| 1062 | * Used by an application to read arbitrary number of bytes from an |
| 1063 | * SCM port. Same semantics as libc read, except that scm_c_read only |
| 1064 | * returns less than SIZE bytes if at end-of-file. |
| 1065 | * |
| 1066 | * Warning: Doesn't update port line and column counts! */ |
| 1067 | |
| 1068 | size_t |
| 1069 | scm_c_read (SCM port, void *buffer, size_t size) |
| 1070 | { |
| 1071 | scm_t_port *pt = SCM_PTAB_ENTRY (port); |
| 1072 | size_t n_read = 0, n_available; |
| 1073 | |
| 1074 | if (pt->rw_active == SCM_PORT_WRITE) |
| 1075 | scm_ptobs[SCM_PTOBNUM (port)].flush (port); |
| 1076 | |
| 1077 | if (pt->rw_random) |
| 1078 | pt->rw_active = SCM_PORT_READ; |
| 1079 | |
| 1080 | if (SCM_READ_BUFFER_EMPTY_P (pt)) |
| 1081 | { |
| 1082 | if (scm_fill_input (port) == EOF) |
| 1083 | return 0; |
| 1084 | } |
| 1085 | |
| 1086 | n_available = pt->read_end - pt->read_pos; |
| 1087 | |
| 1088 | while (n_available < size) |
| 1089 | { |
| 1090 | memcpy (buffer, pt->read_pos, n_available); |
| 1091 | buffer = (char *) buffer + n_available; |
| 1092 | pt->read_pos += n_available; |
| 1093 | n_read += n_available; |
| 1094 | |
| 1095 | if (SCM_READ_BUFFER_EMPTY_P (pt)) |
| 1096 | { |
| 1097 | if (scm_fill_input (port) == EOF) |
| 1098 | return n_read; |
| 1099 | } |
| 1100 | |
| 1101 | size -= n_available; |
| 1102 | n_available = pt->read_end - pt->read_pos; |
| 1103 | } |
| 1104 | |
| 1105 | memcpy (buffer, pt->read_pos, size); |
| 1106 | pt->read_pos += size; |
| 1107 | |
| 1108 | return n_read + size; |
| 1109 | } |
| 1110 | |
| 1111 | /* scm_c_write |
| 1112 | * |
| 1113 | * Used by an application to write arbitrary number of bytes to an SCM |
| 1114 | * port. Similar semantics as libc write. However, unlike libc |
| 1115 | * write, scm_c_write writes the requested number of bytes and has no |
| 1116 | * return value. |
| 1117 | * |
| 1118 | * Warning: Doesn't update port line and column counts! |
| 1119 | */ |
| 1120 | |
| 1121 | void |
| 1122 | scm_c_write (SCM port, const void *ptr, size_t size) |
| 1123 | { |
| 1124 | scm_t_port *pt = SCM_PTAB_ENTRY (port); |
| 1125 | scm_t_ptob_descriptor *ptob = &scm_ptobs[SCM_PTOBNUM (port)]; |
| 1126 | |
| 1127 | if (pt->rw_active == SCM_PORT_READ) |
| 1128 | scm_end_input (port); |
| 1129 | |
| 1130 | ptob->write (port, ptr, size); |
| 1131 | |
| 1132 | if (pt->rw_random) |
| 1133 | pt->rw_active = SCM_PORT_WRITE; |
| 1134 | } |
| 1135 | |
| 1136 | void |
| 1137 | scm_flush (SCM port) |
| 1138 | { |
| 1139 | long i = SCM_PTOBNUM (port); |
| 1140 | (scm_ptobs[i].flush) (port); |
| 1141 | } |
| 1142 | |
| 1143 | void |
| 1144 | scm_end_input (SCM port) |
| 1145 | { |
| 1146 | long offset; |
| 1147 | scm_t_port *pt = SCM_PTAB_ENTRY (port); |
| 1148 | |
| 1149 | if (pt->read_buf == pt->putback_buf) |
| 1150 | { |
| 1151 | offset = pt->read_end - pt->read_pos; |
| 1152 | pt->read_buf = pt->saved_read_buf; |
| 1153 | pt->read_pos = pt->saved_read_pos; |
| 1154 | pt->read_end = pt->saved_read_end; |
| 1155 | pt->read_buf_size = pt->saved_read_buf_size; |
| 1156 | } |
| 1157 | else |
| 1158 | offset = 0; |
| 1159 | |
| 1160 | scm_ptobs[SCM_PTOBNUM (port)].end_input (port, offset); |
| 1161 | } |
| 1162 | |
| 1163 | \f |
| 1164 | |
| 1165 | |
| 1166 | void |
| 1167 | scm_ungetc (int c, SCM port) |
| 1168 | #define FUNC_NAME "scm_ungetc" |
| 1169 | { |
| 1170 | scm_t_port *pt = SCM_PTAB_ENTRY (port); |
| 1171 | |
| 1172 | if (pt->read_buf == pt->putback_buf) |
| 1173 | /* already using the put-back buffer. */ |
| 1174 | { |
| 1175 | /* enlarge putback_buf if necessary. */ |
| 1176 | if (pt->read_end == pt->read_buf + pt->read_buf_size |
| 1177 | && pt->read_buf == pt->read_pos) |
| 1178 | { |
| 1179 | size_t new_size = pt->read_buf_size * 2; |
| 1180 | unsigned char *tmp = (unsigned char *) |
| 1181 | scm_gc_realloc (pt->putback_buf, pt->read_buf_size, new_size, |
| 1182 | "putback buffer"); |
| 1183 | |
| 1184 | pt->read_pos = pt->read_buf = pt->putback_buf = tmp; |
| 1185 | pt->read_end = pt->read_buf + pt->read_buf_size; |
| 1186 | pt->read_buf_size = pt->putback_buf_size = new_size; |
| 1187 | } |
| 1188 | |
| 1189 | /* shift any existing bytes to buffer + 1. */ |
| 1190 | if (pt->read_pos == pt->read_end) |
| 1191 | pt->read_end = pt->read_buf + 1; |
| 1192 | else if (pt->read_pos != pt->read_buf + 1) |
| 1193 | { |
| 1194 | int count = pt->read_end - pt->read_pos; |
| 1195 | |
| 1196 | memmove (pt->read_buf + 1, pt->read_pos, count); |
| 1197 | pt->read_end = pt->read_buf + 1 + count; |
| 1198 | } |
| 1199 | |
| 1200 | pt->read_pos = pt->read_buf; |
| 1201 | } |
| 1202 | else |
| 1203 | /* switch to the put-back buffer. */ |
| 1204 | { |
| 1205 | if (pt->putback_buf == NULL) |
| 1206 | { |
| 1207 | pt->putback_buf |
| 1208 | = (unsigned char *) scm_gc_malloc (SCM_INITIAL_PUTBACK_BUF_SIZE, |
| 1209 | "putback buffer"); |
| 1210 | pt->putback_buf_size = SCM_INITIAL_PUTBACK_BUF_SIZE; |
| 1211 | } |
| 1212 | |
| 1213 | pt->saved_read_buf = pt->read_buf; |
| 1214 | pt->saved_read_pos = pt->read_pos; |
| 1215 | pt->saved_read_end = pt->read_end; |
| 1216 | pt->saved_read_buf_size = pt->read_buf_size; |
| 1217 | |
| 1218 | pt->read_pos = pt->read_buf = pt->putback_buf; |
| 1219 | pt->read_end = pt->read_buf + 1; |
| 1220 | pt->read_buf_size = pt->putback_buf_size; |
| 1221 | } |
| 1222 | |
| 1223 | *pt->read_buf = c; |
| 1224 | |
| 1225 | if (pt->rw_random) |
| 1226 | pt->rw_active = SCM_PORT_READ; |
| 1227 | |
| 1228 | if (c == '\n') |
| 1229 | { |
| 1230 | /* What should col be in this case? |
| 1231 | * We'll leave it at -1. |
| 1232 | */ |
| 1233 | SCM_LINUM (port) -= 1; |
| 1234 | } |
| 1235 | else |
| 1236 | SCM_COL(port) -= 1; |
| 1237 | } |
| 1238 | #undef FUNC_NAME |
| 1239 | |
| 1240 | |
| 1241 | void |
| 1242 | scm_ungets (const char *s, int n, SCM port) |
| 1243 | { |
| 1244 | /* This is simple minded and inefficient, but unreading strings is |
| 1245 | * probably not a common operation, and remember that line and |
| 1246 | * column numbers have to be handled... |
| 1247 | * |
| 1248 | * Please feel free to write an optimized version! |
| 1249 | */ |
| 1250 | while (n--) |
| 1251 | scm_ungetc (s[n], port); |
| 1252 | } |
| 1253 | |
| 1254 | |
| 1255 | SCM_DEFINE (scm_peek_char, "peek-char", 0, 1, 0, |
| 1256 | (SCM port), |
| 1257 | "Return the next character available from @var{port},\n" |
| 1258 | "@emph{without} updating @var{port} to point to the following\n" |
| 1259 | "character. If no more characters are available, the\n" |
| 1260 | "end-of-file object is returned.\n" |
| 1261 | "\n" |
| 1262 | "The value returned by\n" |
| 1263 | "a call to @code{peek-char} is the same as the value that would\n" |
| 1264 | "have been returned by a call to @code{read-char} on the same\n" |
| 1265 | "port. The only difference is that the very next call to\n" |
| 1266 | "@code{read-char} or @code{peek-char} on that @var{port} will\n" |
| 1267 | "return the value returned by the preceding call to\n" |
| 1268 | "@code{peek-char}. In particular, a call to @code{peek-char} on\n" |
| 1269 | "an interactive port will hang waiting for input whenever a call\n" |
| 1270 | "to @code{read-char} would have hung.") |
| 1271 | #define FUNC_NAME s_scm_peek_char |
| 1272 | { |
| 1273 | int c, column; |
| 1274 | if (SCM_UNBNDP (port)) |
| 1275 | port = scm_cur_inp; |
| 1276 | else |
| 1277 | SCM_VALIDATE_OPINPORT (1, port); |
| 1278 | column = SCM_COL(port); |
| 1279 | c = scm_getc (port); |
| 1280 | if (EOF == c) |
| 1281 | return SCM_EOF_VAL; |
| 1282 | scm_ungetc (c, port); |
| 1283 | SCM_COL(port) = column; |
| 1284 | return SCM_MAKE_CHAR (c); |
| 1285 | } |
| 1286 | #undef FUNC_NAME |
| 1287 | |
| 1288 | SCM_DEFINE (scm_unread_char, "unread-char", 1, 1, 0, |
| 1289 | (SCM cobj, SCM port), |
| 1290 | "Place @var{char} in @var{port} so that it will be read by the\n" |
| 1291 | "next read operation. If called multiple times, the unread characters\n" |
| 1292 | "will be read again in last-in first-out order. If @var{port} is\n" |
| 1293 | "not supplied, the current input port is used.") |
| 1294 | #define FUNC_NAME s_scm_unread_char |
| 1295 | { |
| 1296 | int c; |
| 1297 | |
| 1298 | SCM_VALIDATE_CHAR (1, cobj); |
| 1299 | if (SCM_UNBNDP (port)) |
| 1300 | port = scm_cur_inp; |
| 1301 | else |
| 1302 | SCM_VALIDATE_OPINPORT (2, port); |
| 1303 | |
| 1304 | c = SCM_CHAR (cobj); |
| 1305 | |
| 1306 | scm_ungetc (c, port); |
| 1307 | return cobj; |
| 1308 | } |
| 1309 | #undef FUNC_NAME |
| 1310 | |
| 1311 | SCM_DEFINE (scm_unread_string, "unread-string", 2, 0, 0, |
| 1312 | (SCM str, SCM port), |
| 1313 | "Place the string @var{str} in @var{port} so that its characters will be\n" |
| 1314 | "read in subsequent read operations. If called multiple times, the\n" |
| 1315 | "unread characters will be read again in last-in first-out order. If\n" |
| 1316 | "@var{port} is not supplied, the current-input-port is used.") |
| 1317 | #define FUNC_NAME s_scm_unread_string |
| 1318 | { |
| 1319 | SCM_VALIDATE_STRING (1, str); |
| 1320 | if (SCM_UNBNDP (port)) |
| 1321 | port = scm_cur_inp; |
| 1322 | else |
| 1323 | SCM_VALIDATE_OPINPORT (2, port); |
| 1324 | |
| 1325 | scm_ungets (SCM_I_STRING_CHARS (str), SCM_I_STRING_LENGTH (str), port); |
| 1326 | |
| 1327 | return str; |
| 1328 | } |
| 1329 | #undef FUNC_NAME |
| 1330 | |
| 1331 | SCM_DEFINE (scm_seek, "seek", 3, 0, 0, |
| 1332 | (SCM fd_port, SCM offset, SCM whence), |
| 1333 | "Sets the current position of @var{fd/port} to the integer\n" |
| 1334 | "@var{offset}, which is interpreted according to the value of\n" |
| 1335 | "@var{whence}.\n" |
| 1336 | "\n" |
| 1337 | "One of the following variables should be supplied for\n" |
| 1338 | "@var{whence}:\n" |
| 1339 | "@defvar SEEK_SET\n" |
| 1340 | "Seek from the beginning of the file.\n" |
| 1341 | "@end defvar\n" |
| 1342 | "@defvar SEEK_CUR\n" |
| 1343 | "Seek from the current position.\n" |
| 1344 | "@end defvar\n" |
| 1345 | "@defvar SEEK_END\n" |
| 1346 | "Seek from the end of the file.\n" |
| 1347 | "@end defvar\n" |
| 1348 | "If @var{fd/port} is a file descriptor, the underlying system\n" |
| 1349 | "call is @code{lseek}. @var{port} may be a string port.\n" |
| 1350 | "\n" |
| 1351 | "The value returned is the new position in the file. This means\n" |
| 1352 | "that the current position of a port can be obtained using:\n" |
| 1353 | "@lisp\n" |
| 1354 | "(seek port 0 SEEK_CUR)\n" |
| 1355 | "@end lisp") |
| 1356 | #define FUNC_NAME s_scm_seek |
| 1357 | { |
| 1358 | off_t off; |
| 1359 | off_t rv; |
| 1360 | int how; |
| 1361 | |
| 1362 | fd_port = SCM_COERCE_OUTPORT (fd_port); |
| 1363 | |
| 1364 | if (sizeof (off_t) == sizeof (scm_t_intmax)) |
| 1365 | off = scm_to_intmax (offset); |
| 1366 | else |
| 1367 | off = scm_to_long (offset); |
| 1368 | how = scm_to_int (whence); |
| 1369 | |
| 1370 | if (how != SEEK_SET && how != SEEK_CUR && how != SEEK_END) |
| 1371 | SCM_OUT_OF_RANGE (3, whence); |
| 1372 | if (SCM_OPPORTP (fd_port)) |
| 1373 | { |
| 1374 | scm_t_ptob_descriptor *ptob = scm_ptobs + SCM_PTOBNUM (fd_port); |
| 1375 | |
| 1376 | if (!ptob->seek) |
| 1377 | SCM_MISC_ERROR ("port is not seekable", |
| 1378 | scm_cons (fd_port, SCM_EOL)); |
| 1379 | else |
| 1380 | rv = ptob->seek (fd_port, off, how); |
| 1381 | } |
| 1382 | else /* file descriptor?. */ |
| 1383 | { |
| 1384 | rv = lseek (scm_to_int (fd_port), off, how); |
| 1385 | if (rv == -1) |
| 1386 | SCM_SYSERROR; |
| 1387 | } |
| 1388 | return scm_from_intmax (rv); |
| 1389 | } |
| 1390 | #undef FUNC_NAME |
| 1391 | |
| 1392 | #ifdef __MINGW32__ |
| 1393 | /* Define this function since it is not supported under Windows. */ |
| 1394 | static int truncate (char *file, int length) |
| 1395 | { |
| 1396 | int ret = -1, fdes; |
| 1397 | if ((fdes = open (file, O_BINARY | O_WRONLY)) != -1) |
| 1398 | { |
| 1399 | ret = chsize (fdes, length); |
| 1400 | close (fdes); |
| 1401 | } |
| 1402 | return ret; |
| 1403 | } |
| 1404 | #endif /* __MINGW32__ */ |
| 1405 | |
| 1406 | SCM_DEFINE (scm_truncate_file, "truncate-file", 1, 1, 0, |
| 1407 | (SCM object, SCM length), |
| 1408 | "Truncates the object referred to by @var{object} to at most\n" |
| 1409 | "@var{length} bytes. @var{object} can be a string containing a\n" |
| 1410 | "file name or an integer file descriptor or a port.\n" |
| 1411 | "@var{length} may be omitted if @var{object} is not a file name,\n" |
| 1412 | "in which case the truncation occurs at the current port\n" |
| 1413 | "position. The return value is unspecified.") |
| 1414 | #define FUNC_NAME s_scm_truncate_file |
| 1415 | { |
| 1416 | int rv; |
| 1417 | off_t c_length; |
| 1418 | |
| 1419 | /* object can be a port, fdes or filename. */ |
| 1420 | |
| 1421 | if (SCM_UNBNDP (length)) |
| 1422 | { |
| 1423 | /* must supply length if object is a filename. */ |
| 1424 | if (scm_is_string (object)) |
| 1425 | SCM_MISC_ERROR("must supply length if OBJECT is a filename", SCM_EOL); |
| 1426 | |
| 1427 | length = scm_seek (object, SCM_INUM0, scm_from_int (SEEK_CUR)); |
| 1428 | } |
| 1429 | c_length = scm_to_size_t (length); |
| 1430 | |
| 1431 | object = SCM_COERCE_OUTPORT (object); |
| 1432 | if (scm_is_integer (object)) |
| 1433 | { |
| 1434 | SCM_SYSCALL (rv = ftruncate (scm_to_int (object), c_length)); |
| 1435 | } |
| 1436 | else if (SCM_OPOUTPORTP (object)) |
| 1437 | { |
| 1438 | scm_t_port *pt = SCM_PTAB_ENTRY (object); |
| 1439 | scm_t_ptob_descriptor *ptob = scm_ptobs + SCM_PTOBNUM (object); |
| 1440 | |
| 1441 | if (!ptob->truncate) |
| 1442 | SCM_MISC_ERROR ("port is not truncatable", SCM_EOL); |
| 1443 | if (pt->rw_active == SCM_PORT_READ) |
| 1444 | scm_end_input (object); |
| 1445 | else if (pt->rw_active == SCM_PORT_WRITE) |
| 1446 | ptob->flush (object); |
| 1447 | |
| 1448 | ptob->truncate (object, c_length); |
| 1449 | rv = 0; |
| 1450 | } |
| 1451 | else |
| 1452 | { |
| 1453 | char *str = scm_to_locale_string (object); |
| 1454 | int eno; |
| 1455 | SCM_SYSCALL (rv = truncate (str, c_length)); |
| 1456 | eno = errno; |
| 1457 | free (str); |
| 1458 | errno = eno; |
| 1459 | } |
| 1460 | if (rv == -1) |
| 1461 | SCM_SYSERROR; |
| 1462 | return SCM_UNSPECIFIED; |
| 1463 | } |
| 1464 | #undef FUNC_NAME |
| 1465 | |
| 1466 | SCM_DEFINE (scm_port_line, "port-line", 1, 0, 0, |
| 1467 | (SCM port), |
| 1468 | "Return the current line number for @var{port}.\n" |
| 1469 | "\n" |
| 1470 | "The first line of a file is 0. But you might want to add 1\n" |
| 1471 | "when printing line numbers, since starting from 1 is\n" |
| 1472 | "traditional in error messages, and likely to be more natural to\n" |
| 1473 | "non-programmers.") |
| 1474 | #define FUNC_NAME s_scm_port_line |
| 1475 | { |
| 1476 | port = SCM_COERCE_OUTPORT (port); |
| 1477 | SCM_VALIDATE_OPENPORT (1, port); |
| 1478 | return scm_from_int (SCM_LINUM (port)); |
| 1479 | } |
| 1480 | #undef FUNC_NAME |
| 1481 | |
| 1482 | SCM_DEFINE (scm_set_port_line_x, "set-port-line!", 2, 0, 0, |
| 1483 | (SCM port, SCM line), |
| 1484 | "Set the current line number for @var{port} to @var{line}. The\n" |
| 1485 | "first line of a file is 0.") |
| 1486 | #define FUNC_NAME s_scm_set_port_line_x |
| 1487 | { |
| 1488 | port = SCM_COERCE_OUTPORT (port); |
| 1489 | SCM_VALIDATE_OPENPORT (1, port); |
| 1490 | SCM_PTAB_ENTRY (port)->line_number = scm_to_int (line); |
| 1491 | return SCM_UNSPECIFIED; |
| 1492 | } |
| 1493 | #undef FUNC_NAME |
| 1494 | |
| 1495 | SCM_DEFINE (scm_port_column, "port-column", 1, 0, 0, |
| 1496 | (SCM port), |
| 1497 | "Return the current column number of @var{port}.\n" |
| 1498 | "If the number is\n" |
| 1499 | "unknown, the result is #f. Otherwise, the result is a 0-origin integer\n" |
| 1500 | "- i.e. the first character of the first line is line 0, column 0.\n" |
| 1501 | "(However, when you display a file position, for example in an error\n" |
| 1502 | "message, we recommend you add 1 to get 1-origin integers. This is\n" |
| 1503 | "because lines and column numbers traditionally start with 1, and that is\n" |
| 1504 | "what non-programmers will find most natural.)") |
| 1505 | #define FUNC_NAME s_scm_port_column |
| 1506 | { |
| 1507 | port = SCM_COERCE_OUTPORT (port); |
| 1508 | SCM_VALIDATE_OPENPORT (1, port); |
| 1509 | return scm_from_int (SCM_COL (port)); |
| 1510 | } |
| 1511 | #undef FUNC_NAME |
| 1512 | |
| 1513 | SCM_DEFINE (scm_set_port_column_x, "set-port-column!", 2, 0, 0, |
| 1514 | (SCM port, SCM column), |
| 1515 | "Set the current column of @var{port}. Before reading the first\n" |
| 1516 | "character on a line the column should be 0.") |
| 1517 | #define FUNC_NAME s_scm_set_port_column_x |
| 1518 | { |
| 1519 | port = SCM_COERCE_OUTPORT (port); |
| 1520 | SCM_VALIDATE_OPENPORT (1, port); |
| 1521 | SCM_PTAB_ENTRY (port)->column_number = scm_to_int (column); |
| 1522 | return SCM_UNSPECIFIED; |
| 1523 | } |
| 1524 | #undef FUNC_NAME |
| 1525 | |
| 1526 | SCM_DEFINE (scm_port_filename, "port-filename", 1, 0, 0, |
| 1527 | (SCM port), |
| 1528 | "Return the filename associated with @var{port}. This function returns\n" |
| 1529 | "the strings \"standard input\", \"standard output\" and \"standard error\"\n" |
| 1530 | "when called on the current input, output and error ports respectively.") |
| 1531 | #define FUNC_NAME s_scm_port_filename |
| 1532 | { |
| 1533 | port = SCM_COERCE_OUTPORT (port); |
| 1534 | SCM_VALIDATE_OPENPORT (1, port); |
| 1535 | return SCM_FILENAME (port); |
| 1536 | } |
| 1537 | #undef FUNC_NAME |
| 1538 | |
| 1539 | SCM_DEFINE (scm_set_port_filename_x, "set-port-filename!", 2, 0, 0, |
| 1540 | (SCM port, SCM filename), |
| 1541 | "Change the filename associated with @var{port}, using the current input\n" |
| 1542 | "port if none is specified. Note that this does not change the port's\n" |
| 1543 | "source of data, but only the value that is returned by\n" |
| 1544 | "@code{port-filename} and reported in diagnostic output.") |
| 1545 | #define FUNC_NAME s_scm_set_port_filename_x |
| 1546 | { |
| 1547 | port = SCM_COERCE_OUTPORT (port); |
| 1548 | SCM_VALIDATE_OPENPORT (1, port); |
| 1549 | /* We allow the user to set the filename to whatever he likes. */ |
| 1550 | SCM_SET_FILENAME (port, filename); |
| 1551 | return SCM_UNSPECIFIED; |
| 1552 | } |
| 1553 | #undef FUNC_NAME |
| 1554 | |
| 1555 | void |
| 1556 | scm_print_port_mode (SCM exp, SCM port) |
| 1557 | { |
| 1558 | scm_puts (SCM_CLOSEDP (exp) |
| 1559 | ? "closed: " |
| 1560 | : (SCM_RDNG & SCM_CELL_WORD_0 (exp) |
| 1561 | ? (SCM_WRTNG & SCM_CELL_WORD_0 (exp) |
| 1562 | ? "input-output: " |
| 1563 | : "input: ") |
| 1564 | : (SCM_WRTNG & SCM_CELL_WORD_0 (exp) |
| 1565 | ? "output: " |
| 1566 | : "bogus: ")), |
| 1567 | port); |
| 1568 | } |
| 1569 | |
| 1570 | int |
| 1571 | scm_port_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED) |
| 1572 | { |
| 1573 | char *type = SCM_PTOBNAME (SCM_PTOBNUM (exp)); |
| 1574 | if (!type) |
| 1575 | type = "port"; |
| 1576 | scm_puts ("#<", port); |
| 1577 | scm_print_port_mode (exp, port); |
| 1578 | scm_puts (type, port); |
| 1579 | scm_putc (' ', port); |
| 1580 | scm_intprint (SCM_CELL_WORD_1 (exp), 16, port); |
| 1581 | scm_putc ('>', port); |
| 1582 | return 1; |
| 1583 | } |
| 1584 | |
| 1585 | void |
| 1586 | scm_ports_prehistory () |
| 1587 | { |
| 1588 | scm_numptob = 0; |
| 1589 | scm_ptobs = (scm_t_ptob_descriptor *) scm_malloc (sizeof (scm_t_ptob_descriptor)); |
| 1590 | } |
| 1591 | |
| 1592 | \f |
| 1593 | |
| 1594 | /* Void ports. */ |
| 1595 | |
| 1596 | scm_t_bits scm_tc16_void_port = 0; |
| 1597 | |
| 1598 | static int fill_input_void_port (SCM port SCM_UNUSED) |
| 1599 | { |
| 1600 | return EOF; |
| 1601 | } |
| 1602 | |
| 1603 | static void |
| 1604 | write_void_port (SCM port SCM_UNUSED, |
| 1605 | const void *data SCM_UNUSED, |
| 1606 | size_t size SCM_UNUSED) |
| 1607 | { |
| 1608 | } |
| 1609 | |
| 1610 | static SCM |
| 1611 | scm_i_void_port (long mode_bits) |
| 1612 | { |
| 1613 | scm_mutex_lock (&scm_i_port_table_mutex); |
| 1614 | { |
| 1615 | SCM answer = scm_new_port_table_entry (scm_tc16_void_port); |
| 1616 | scm_t_port * pt = SCM_PTAB_ENTRY(answer); |
| 1617 | |
| 1618 | scm_port_non_buffer (pt); |
| 1619 | |
| 1620 | SCM_SETSTREAM (answer, 0); |
| 1621 | SCM_SET_CELL_TYPE (answer, scm_tc16_void_port | mode_bits); |
| 1622 | scm_mutex_unlock (&scm_i_port_table_mutex); |
| 1623 | return answer; |
| 1624 | } |
| 1625 | } |
| 1626 | |
| 1627 | SCM |
| 1628 | scm_void_port (char *mode_str) |
| 1629 | { |
| 1630 | return scm_i_void_port (scm_mode_bits (mode_str)); |
| 1631 | } |
| 1632 | |
| 1633 | SCM_DEFINE (scm_sys_make_void_port, "%make-void-port", 1, 0, 0, |
| 1634 | (SCM mode), |
| 1635 | "Create and return a new void port. A void port acts like\n" |
| 1636 | "@file{/dev/null}. The @var{mode} argument\n" |
| 1637 | "specifies the input/output modes for this port: see the\n" |
| 1638 | "documentation for @code{open-file} in @ref{File Ports}.") |
| 1639 | #define FUNC_NAME s_scm_sys_make_void_port |
| 1640 | { |
| 1641 | return scm_i_void_port (scm_i_mode_bits (mode)); |
| 1642 | } |
| 1643 | #undef FUNC_NAME |
| 1644 | |
| 1645 | \f |
| 1646 | /* Initialization. */ |
| 1647 | |
| 1648 | void |
| 1649 | scm_init_ports () |
| 1650 | { |
| 1651 | /* lseek() symbols. */ |
| 1652 | scm_c_define ("SEEK_SET", scm_from_int (SEEK_SET)); |
| 1653 | scm_c_define ("SEEK_CUR", scm_from_int (SEEK_CUR)); |
| 1654 | scm_c_define ("SEEK_END", scm_from_int (SEEK_END)); |
| 1655 | |
| 1656 | scm_tc16_void_port = scm_make_port_type ("void", fill_input_void_port, |
| 1657 | write_void_port); |
| 1658 | #include "libguile/ports.x" |
| 1659 | } |
| 1660 | |
| 1661 | /* |
| 1662 | Local Variables: |
| 1663 | c-file-style: "gnu" |
| 1664 | End: |
| 1665 | */ |