gdb/ui-file.c

   1 /* UI_FILE - a generic STDIO like output stream.
   2
   3    Copyright (C) 1999-2002, 2007-2012 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 /* Implement the ``struct ui_file'' object.  */
  21
  22 #include "defs.h"
  23 #include "ui-file.h"
  24 #include "gdb_obstack.h"
  25 #include "gdb_string.h"
  26 #include "gdb_select.h"
  27
  28 #include <errno.h>
  29
  30 static ui_file_isatty_ftype null_file_isatty;
  31 static ui_file_write_ftype null_file_write;
  32 static ui_file_write_ftype null_file_write_async_safe;
  33 static ui_file_fputs_ftype null_file_fputs;
  34 static ui_file_read_ftype null_file_read;
  35 static ui_file_flush_ftype null_file_flush;
  36 static ui_file_delete_ftype null_file_delete;
  37 static ui_file_rewind_ftype null_file_rewind;
  38 static ui_file_put_ftype null_file_put;
  39
  40 struct ui_file
  41   {
  42     int *magic;
  43     ui_file_flush_ftype *to_flush;
  44     ui_file_write_ftype *to_write;
  45     ui_file_write_async_safe_ftype *to_write_async_safe;
  46     ui_file_fputs_ftype *to_fputs;
  47     ui_file_read_ftype *to_read;
  48     ui_file_delete_ftype *to_delete;
  49     ui_file_isatty_ftype *to_isatty;
  50     ui_file_rewind_ftype *to_rewind;
  51     ui_file_put_ftype *to_put;
  52     void *to_data;
  53   };
  54 int ui_file_magic;
  55
  56 struct ui_file *
  57 ui_file_new (void)
  58 {
  59   struct ui_file *file = xmalloc (sizeof (struct ui_file));
  60
  61   file->magic = &ui_file_magic;
  62   set_ui_file_data (file, NULL, null_file_delete);
  63   set_ui_file_flush (file, null_file_flush);
  64   set_ui_file_write (file, null_file_write);
  65   set_ui_file_write_async_safe (file, null_file_write_async_safe);
  66   set_ui_file_fputs (file, null_file_fputs);
  67   set_ui_file_read (file, null_file_read);
  68   set_ui_file_isatty (file, null_file_isatty);
  69   set_ui_file_rewind (file, null_file_rewind);
  70   set_ui_file_put (file, null_file_put);
  71   return file;
  72 }
  73
  74 void
  75 ui_file_delete (struct ui_file *file)
  76 {
  77   file->to_delete (file);
  78   xfree (file);
  79 }
  80
  81 static int
  82 null_file_isatty (struct ui_file *file)
  83 {
  84   return 0;
  85 }
  86
  87 static void
  88 null_file_rewind (struct ui_file *file)
  89 {
  90   return;
  91 }
  92
  93 static void
  94 null_file_put (struct ui_file *file,
  95                ui_file_put_method_ftype *write,
  96                void *dest)
  97 {
  98   return;
  99 }
 100
 101 static void
 102 null_file_flush (struct ui_file *file)
 103 {
 104   return;
 105 }
 106
 107 static void
 108 null_file_write (struct ui_file *file,
 109                  const char *buf,
 110                  long sizeof_buf)
 111 {
 112   if (file->to_fputs == null_file_fputs)
 113     /* Both the write and fputs methods are null.  Discard the
 114        request.  */
 115     return;
 116   else
 117     {
 118       /* The fputs method isn't null, slowly pass the write request
 119          onto that.  FYI, this isn't as bad as it may look - the
 120          current (as of 1999-11-07) printf_* function calls fputc and
 121          fputc does exactly the below.  By having a write function it
 122          is possible to clean up that code.  */
 123       int i;
 124       char b[2];
 125
 126       b[1] = '\0';
 127       for (i = 0; i < sizeof_buf; i++)
 128         {
 129           b[0] = buf[i];
 130           file->to_fputs (b, file);
 131         }
 132       return;
 133     }
 134 }
 135
 136 static long
 137 null_file_read (struct ui_file *file,
 138                 char *buf,
 139                 long sizeof_buf)
 140 {
 141   errno = EBADF;
 142   return 0;
 143 }
 144
 145 static void
 146 null_file_fputs (const char *buf, struct ui_file *file)
 147 {
 148   if (file->to_write == null_file_write)
 149     /* Both the write and fputs methods are null.  Discard the
 150        request.  */
 151     return;
 152   else
 153     {
 154       /* The write method was implemented, use that.  */
 155       file->to_write (file, buf, strlen (buf));
 156     }
 157 }
 158
 159 static void
 160 null_file_write_async_safe (struct ui_file *file,
 161                             const char *buf,
 162                             long sizeof_buf)
 163 {
 164   return;
 165 }
 166
 167 static void
 168 null_file_delete (struct ui_file *file)
 169 {
 170   return;
 171 }
 172
 173 void *
 174 ui_file_data (struct ui_file *file)
 175 {
 176   if (file->magic != &ui_file_magic)
 177     internal_error (__FILE__, __LINE__,
 178                     _("ui_file_data: bad magic number"));
 179   return file->to_data;
 180 }
 181
 182 void
 183 gdb_flush (struct ui_file *file)
 184 {
 185   file->to_flush (file);
 186 }
 187
 188 int
 189 ui_file_isatty (struct ui_file *file)
 190 {
 191   return file->to_isatty (file);
 192 }
 193
 194 void
 195 ui_file_rewind (struct ui_file *file)
 196 {
 197   file->to_rewind (file);
 198 }
 199
 200 void
 201 ui_file_put (struct ui_file *file,
 202               ui_file_put_method_ftype *write,
 203               void *dest)
 204 {
 205   file->to_put (file, write, dest);
 206 }
 207
 208 void
 209 ui_file_write (struct ui_file *file,
 210                 const char *buf,
 211                 long length_buf)
 212 {
 213   file->to_write (file, buf, length_buf);
 214 }
 215
 216 void
 217 ui_file_write_async_safe (struct ui_file *file,
 218                           const char *buf,
 219                           long length_buf)
 220 {
 221   file->to_write_async_safe (file, buf, length_buf);
 222 }
 223
 224 long
 225 ui_file_read (struct ui_file *file, char *buf, long length_buf)
 226 {
 227   return file->to_read (file, buf, length_buf);
 228 }
 229
 230 void
 231 fputs_unfiltered (const char *buf, struct ui_file *file)
 232 {
 233   file->to_fputs (buf, file);
 234 }
 235
 236 void
 237 set_ui_file_flush (struct ui_file *file, ui_file_flush_ftype *flush)
 238 {
 239   file->to_flush = flush;
 240 }
 241
 242 void
 243 set_ui_file_isatty (struct ui_file *file, ui_file_isatty_ftype *isatty)
 244 {
 245   file->to_isatty = isatty;
 246 }
 247
 248 void
 249 set_ui_file_rewind (struct ui_file *file, ui_file_rewind_ftype *rewind)
 250 {
 251   file->to_rewind = rewind;
 252 }
 253
 254 void
 255 set_ui_file_put (struct ui_file *file, ui_file_put_ftype *put)
 256 {
 257   file->to_put = put;
 258 }
 259
 260 void
 261 set_ui_file_write (struct ui_file *file,
 262                     ui_file_write_ftype *write)
 263 {
 264   file->to_write = write;
 265 }
 266
 267 void
 268 set_ui_file_write_async_safe (struct ui_file *file,
 269                               ui_file_write_async_safe_ftype *write_async_safe)
 270 {
 271   file->to_write_async_safe = write_async_safe;
 272 }
 273
 274 void
 275 set_ui_file_read (struct ui_file *file, ui_file_read_ftype *read)
 276 {
 277   file->to_read = read;
 278 }
 279
 280 void
 281 set_ui_file_fputs (struct ui_file *file, ui_file_fputs_ftype *fputs)
 282 {
 283   file->to_fputs = fputs;
 284 }
 285
 286 void
 287 set_ui_file_data (struct ui_file *file, void *data,
 288                   ui_file_delete_ftype *delete)
 289 {
 290   file->to_data = data;
 291   file->to_delete = delete;
 292 }
 293
 294 /* ui_file utility function for converting a ``struct ui_file'' into
 295    a memory buffer.  */
 296
 297 struct accumulated_ui_file
 298 {
 299   char *buffer;
 300   long length;
 301 };
 302
 303 static void
 304 do_ui_file_xstrdup (void *context, const char *buffer, long length)
 305 {
 306   struct accumulated_ui_file *acc = context;
 307
 308   if (acc->buffer == NULL)
 309     acc->buffer = xmalloc (length + 1);
 310   else
 311     acc->buffer = xrealloc (acc->buffer, acc->length + length + 1);
 312   memcpy (acc->buffer + acc->length, buffer, length);
 313   acc->length += length;
 314   acc->buffer[acc->length] = '\0';
 315 }
 316
 317 char *
 318 ui_file_xstrdup (struct ui_file *file, long *length)
 319 {
 320   struct accumulated_ui_file acc;
 321
 322   acc.buffer = NULL;
 323   acc.length = 0;
 324   ui_file_put (file, do_ui_file_xstrdup, &acc);
 325   if (acc.buffer == NULL)
 326     acc.buffer = xstrdup ("");
 327   if (length != NULL)
 328     *length = acc.length;
 329   return acc.buffer;
 330 }
 331
 332 static void
 333 do_ui_file_obsavestring (void *context, const char *buffer, long length)
 334 {
 335   struct obstack *obstack = (struct obstack *) context;
 336
 337   obstack_grow (obstack, buffer, length);
 338 }
 339
 340 char *
 341 ui_file_obsavestring (struct ui_file *file, struct obstack *obstack,
 342                       long *length)
 343 {
 344   ui_file_put (file, do_ui_file_obsavestring, obstack);
 345   *length = obstack_object_size (obstack);
 346   obstack_1grow (obstack, '\0');
 347   return obstack_finish (obstack);
 348 }
 349 \f
 350 /* A pure memory based ``struct ui_file'' that can be used an output
 351    buffer.  The buffers accumulated contents are available via
 352    ui_file_put().  */
 353
 354 struct mem_file
 355   {
 356     int *magic;
 357     char *buffer;
 358     int sizeof_buffer;
 359     int length_buffer;
 360   };
 361
 362 static ui_file_rewind_ftype mem_file_rewind;
 363 static ui_file_put_ftype mem_file_put;
 364 static ui_file_write_ftype mem_file_write;
 365 static ui_file_delete_ftype mem_file_delete;
 366 static struct ui_file *mem_file_new (void);
 367 static int mem_file_magic;
 368
 369 static struct ui_file *
 370 mem_file_new (void)
 371 {
 372   struct mem_file *stream = XMALLOC (struct mem_file);
 373   struct ui_file *file = ui_file_new ();
 374
 375   set_ui_file_data (file, stream, mem_file_delete);
 376   set_ui_file_rewind (file, mem_file_rewind);
 377   set_ui_file_put (file, mem_file_put);
 378   set_ui_file_write (file, mem_file_write);
 379   stream->magic = &mem_file_magic;
 380   stream->buffer = NULL;
 381   stream->sizeof_buffer = 0;
 382   stream->length_buffer = 0;
 383   return file;
 384 }
 385
 386 static void
 387 mem_file_delete (struct ui_file *file)
 388 {
 389   struct mem_file *stream = ui_file_data (file);
 390
 391   if (stream->magic != &mem_file_magic)
 392     internal_error (__FILE__, __LINE__,
 393                     _("mem_file_delete: bad magic number"));
 394   if (stream->buffer != NULL)
 395     xfree (stream->buffer);
 396   xfree (stream);
 397 }
 398
 399 struct ui_file *
 400 mem_fileopen (void)
 401 {
 402   return mem_file_new ();
 403 }
 404
 405 static void
 406 mem_file_rewind (struct ui_file *file)
 407 {
 408   struct mem_file *stream = ui_file_data (file);
 409
 410   if (stream->magic != &mem_file_magic)
 411     internal_error (__FILE__, __LINE__,
 412                     _("mem_file_rewind: bad magic number"));
 413   stream->length_buffer = 0;
 414 }
 415
 416 static void
 417 mem_file_put (struct ui_file *file,
 418               ui_file_put_method_ftype *write,
 419               void *dest)
 420 {
 421   struct mem_file *stream = ui_file_data (file);
 422
 423   if (stream->magic != &mem_file_magic)
 424     internal_error (__FILE__, __LINE__,
 425                     _("mem_file_put: bad magic number"));
 426   if (stream->length_buffer > 0)
 427     write (dest, stream->buffer, stream->length_buffer);
 428 }
 429
 430 void
 431 mem_file_write (struct ui_file *file,
 432                 const char *buffer,
 433                 long length_buffer)
 434 {
 435   struct mem_file *stream = ui_file_data (file);
 436
 437   if (stream->magic != &mem_file_magic)
 438     internal_error (__FILE__, __LINE__,
 439                     _("mem_file_write: bad magic number"));
 440   if (stream->buffer == NULL)
 441     {
 442       stream->length_buffer = length_buffer;
 443       stream->sizeof_buffer = length_buffer;
 444       stream->buffer = xmalloc (stream->sizeof_buffer);
 445       memcpy (stream->buffer, buffer, length_buffer);
 446     }
 447   else
 448     {
 449       int new_length = stream->length_buffer + length_buffer;
 450
 451       if (new_length >= stream->sizeof_buffer)
 452         {
 453           stream->sizeof_buffer = new_length;
 454           stream->buffer = xrealloc (stream->buffer, stream->sizeof_buffer);
 455         }
 456       memcpy (stream->buffer + stream->length_buffer, buffer, length_buffer);
 457       stream->length_buffer = new_length;
 458     }
 459 }
 460 \f
 461 /* ``struct ui_file'' implementation that maps directly onto
 462    <stdio.h>'s FILE.  */
 463
 464 static ui_file_write_ftype stdio_file_write;
 465 static ui_file_write_async_safe_ftype stdio_file_write_async_safe;
 466 static ui_file_fputs_ftype stdio_file_fputs;
 467 static ui_file_read_ftype stdio_file_read;
 468 static ui_file_isatty_ftype stdio_file_isatty;
 469 static ui_file_delete_ftype stdio_file_delete;
 470 static struct ui_file *stdio_file_new (FILE *file, int close_p);
 471 static ui_file_flush_ftype stdio_file_flush;
 472
 473 static int stdio_file_magic;
 474
 475 struct stdio_file
 476   {
 477     int *magic;
 478     FILE *file;
 479     /* The associated file descriptor is extracted ahead of time for
 480        stdio_file_write_async_safe's benefit, in case fileno isn't async-safe.  */
 481     int fd;
 482     int close_p;
 483   };
 484
 485 static struct ui_file *
 486 stdio_file_new (FILE *file, int close_p)
 487 {
 488   struct ui_file *ui_file = ui_file_new ();
 489   struct stdio_file *stdio = xmalloc (sizeof (struct stdio_file));
 490
 491   stdio->magic = &stdio_file_magic;
 492   stdio->file = file;
 493   stdio->fd = fileno (file);
 494   stdio->close_p = close_p;
 495   set_ui_file_data (ui_file, stdio, stdio_file_delete);
 496   set_ui_file_flush (ui_file, stdio_file_flush);
 497   set_ui_file_write (ui_file, stdio_file_write);
 498   set_ui_file_write_async_safe (ui_file, stdio_file_write_async_safe);
 499   set_ui_file_fputs (ui_file, stdio_file_fputs);
 500   set_ui_file_read (ui_file, stdio_file_read);
 501   set_ui_file_isatty (ui_file, stdio_file_isatty);
 502   return ui_file;
 503 }
 504
 505 static void
 506 stdio_file_delete (struct ui_file *file)
 507 {
 508   struct stdio_file *stdio = ui_file_data (file);
 509
 510   if (stdio->magic != &stdio_file_magic)
 511     internal_error (__FILE__, __LINE__,
 512                     _("stdio_file_delete: bad magic number"));
 513   if (stdio->close_p)
 514     {
 515       fclose (stdio->file);
 516     }
 517   xfree (stdio);
 518 }
 519
 520 static void
 521 stdio_file_flush (struct ui_file *file)
 522 {
 523   struct stdio_file *stdio = ui_file_data (file);
 524
 525   if (stdio->magic != &stdio_file_magic)
 526     internal_error (__FILE__, __LINE__,
 527                     _("stdio_file_flush: bad magic number"));
 528   fflush (stdio->file);
 529 }
 530
 531 static long
 532 stdio_file_read (struct ui_file *file, char *buf, long length_buf)
 533 {
 534   struct stdio_file *stdio = ui_file_data (file);
 535
 536   if (stdio->magic != &stdio_file_magic)
 537     internal_error (__FILE__, __LINE__,
 538                     _("stdio_file_read: bad magic number"));
 539
 540   /* For the benefit of Windows, call gdb_select before reading from
 541      the file.  Wait until at least one byte of data is available.
 542      Control-C can interrupt gdb_select, but not read.  */
 543   {
 544     fd_set readfds;
 545     FD_ZERO (&readfds);
 546     FD_SET (stdio->fd, &readfds);
 547     if (gdb_select (stdio->fd + 1, &readfds, NULL, NULL, NULL) == -1)
 548       return -1;
 549   }
 550
 551   return read (stdio->fd, buf, length_buf);
 552 }
 553
 554 static void
 555 stdio_file_write (struct ui_file *file, const char *buf, long length_buf)
 556 {
 557   struct stdio_file *stdio = ui_file_data (file);
 558
 559   if (stdio->magic != &stdio_file_magic)
 560     internal_error (__FILE__, __LINE__,
 561                     _("stdio_file_write: bad magic number"));
 562   /* Calling error crashes when we are called from the exception framework.  */
 563   if (fwrite (buf, length_buf, 1, stdio->file))
 564     {
 565       /* Nothing.  */
 566     }
 567 }
 568
 569 static void
 570 stdio_file_write_async_safe (struct ui_file *file,
 571                              const char *buf, long length_buf)
 572 {
 573   struct stdio_file *stdio = ui_file_data (file);
 574
 575   if (stdio->magic != &stdio_file_magic)
 576     {
 577       /* gettext isn't necessarily async safe, so we can't use _("error message") here.
 578          We could extract the correct translation ahead of time, but this is an extremely
 579          rare event, and one of the other stdio_file_* routines will presumably catch
 580          the problem anyway.  For now keep it simple and ignore the error here.  */
 581       return;
 582     }
 583
 584   /* This is written the way it is to avoid a warning from gcc about not using the
 585      result of write (since it can be declared with attribute warn_unused_result).
 586      Alas casting to void doesn't work for this.  */
 587   if (write (stdio->fd, buf, length_buf))
 588     {
 589       /* Nothing.  */
 590     }
 591 }
 592
 593 static void
 594 stdio_file_fputs (const char *linebuffer, struct ui_file *file)
 595 {
 596   struct stdio_file *stdio = ui_file_data (file);
 597
 598   if (stdio->magic != &stdio_file_magic)
 599     internal_error (__FILE__, __LINE__,
 600                     _("stdio_file_fputs: bad magic number"));
 601   /* Calling error crashes when we are called from the exception framework.  */
 602   if (fputs (linebuffer, stdio->file))
 603     {
 604       /* Nothing.  */
 605     }
 606 }
 607
 608 static int
 609 stdio_file_isatty (struct ui_file *file)
 610 {
 611   struct stdio_file *stdio = ui_file_data (file);
 612
 613   if (stdio->magic != &stdio_file_magic)
 614     internal_error (__FILE__, __LINE__,
 615                     _("stdio_file_isatty: bad magic number"));
 616   return (isatty (stdio->fd));
 617 }
 618
 619 /* Like fdopen().  Create a ui_file from a previously opened FILE.  */
 620
 621 struct ui_file *
 622 stdio_fileopen (FILE *file)
 623 {
 624   return stdio_file_new (file, 0);
 625 }
 626
 627 struct ui_file *
 628 gdb_fopen (char *name, char *mode)
 629 {
 630   FILE *f = fopen (name, mode);
 631
 632   if (f == NULL)
 633     return NULL;
 634   return stdio_file_new (f, 1);
 635 }
 636
 637 /* ``struct ui_file'' implementation that maps onto two ui-file objects.  */
 638
 639 static ui_file_write_ftype tee_file_write;
 640 static ui_file_fputs_ftype tee_file_fputs;
 641 static ui_file_isatty_ftype tee_file_isatty;
 642 static ui_file_delete_ftype tee_file_delete;
 643 static ui_file_flush_ftype tee_file_flush;
 644
 645 static int tee_file_magic;
 646
 647 struct tee_file
 648   {
 649     int *magic;
 650     struct ui_file *one, *two;
 651     int close_one, close_two;
 652   };
 653
 654 struct ui_file *
 655 tee_file_new (struct ui_file *one, int close_one,
 656               struct ui_file *two, int close_two)
 657 {
 658   struct ui_file *ui_file = ui_file_new ();
 659   struct tee_file *tee = xmalloc (sizeof (struct tee_file));
 660
 661   tee->magic = &tee_file_magic;
 662   tee->one = one;
 663   tee->two = two;
 664   tee->close_one = close_one;
 665   tee->close_two = close_two;
 666   set_ui_file_data (ui_file, tee, tee_file_delete);
 667   set_ui_file_flush (ui_file, tee_file_flush);
 668   set_ui_file_write (ui_file, tee_file_write);
 669   set_ui_file_fputs (ui_file, tee_file_fputs);
 670   set_ui_file_isatty (ui_file, tee_file_isatty);
 671   return ui_file;
 672 }
 673
 674 static void
 675 tee_file_delete (struct ui_file *file)
 676 {
 677   struct tee_file *tee = ui_file_data (file);
 678
 679   if (tee->magic != &tee_file_magic)
 680     internal_error (__FILE__, __LINE__,
 681                     _("tee_file_delete: bad magic number"));
 682   if (tee->close_one)
 683     ui_file_delete (tee->one);
 684   if (tee->close_two)
 685     ui_file_delete (tee->two);
 686
 687   xfree (tee);
 688 }
 689
 690 static void
 691 tee_file_flush (struct ui_file *file)
 692 {
 693   struct tee_file *tee = ui_file_data (file);
 694
 695   if (tee->magic != &tee_file_magic)
 696     internal_error (__FILE__, __LINE__,
 697                     _("tee_file_flush: bad magic number"));
 698   tee->one->to_flush (tee->one);
 699   tee->two->to_flush (tee->two);
 700 }
 701
 702 static void
 703 tee_file_write (struct ui_file *file, const char *buf, long length_buf)
 704 {
 705   struct tee_file *tee = ui_file_data (file);
 706
 707   if (tee->magic != &tee_file_magic)
 708     internal_error (__FILE__, __LINE__,
 709                     _("tee_file_write: bad magic number"));
 710   ui_file_write (tee->one, buf, length_buf);
 711   ui_file_write (tee->two, buf, length_buf);
 712 }
 713
 714 static void
 715 tee_file_fputs (const char *linebuffer, struct ui_file *file)
 716 {
 717   struct tee_file *tee = ui_file_data (file);
 718
 719   if (tee->magic != &tee_file_magic)
 720     internal_error (__FILE__, __LINE__,
 721                     _("tee_file_fputs: bad magic number"));
 722   tee->one->to_fputs (linebuffer, tee->one);
 723   tee->two->to_fputs (linebuffer, tee->two);
 724 }
 725
 726 static int
 727 tee_file_isatty (struct ui_file *file)
 728 {
 729   struct tee_file *tee = ui_file_data (file);
 730
 731   if (tee->magic != &tee_file_magic)
 732     internal_error (__FILE__, __LINE__,
 733                     _("tee_file_isatty: bad magic number"));
 734
 735   return ui_file_isatty (tee->one);
 736 }