sim/common/callback.c

   1 /* Remote target callback routines.
   2    Copyright 1995, 1996, 1997, 2000, 2002, 2003, 2004
   3    Free Software Foundation, Inc.
   4    Contributed by Cygnus Solutions.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GAS; see the file COPYING.  If not, write to the Free Software
  20    Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 /* This file provides a standard way for targets to talk to the host OS
  23    level.  */
  24
  25 #ifdef HAVE_CONFIG_H
  26 #include "cconfig.h"
  27 #endif
  28 #include "ansidecl.h"
  29 #ifdef ANSI_PROTOTYPES
  30 #include <stdarg.h>
  31 #else
  32 #include <varargs.h>
  33 #endif
  34 #include <stdio.h>
  35 #ifdef HAVE_STDLIB_H
  36 #include <stdlib.h>
  37 #endif
  38 #ifdef HAVE_STRING_H
  39 #include <string.h>
  40 #else
  41 #ifdef HAVE_STRINGS_H
  42 #include <strings.h>
  43 #endif
  44 #endif
  45 #ifdef HAVE_LIMITS_H
  46 /* For PIPE_BUF.  */
  47 #include <limits.h>
  48 #endif
  49 #include <errno.h>
  50 #include <fcntl.h>
  51 #include <time.h>
  52 #include <sys/types.h>
  53 #include <sys/stat.h>
  54 #include "gdb/callback.h"
  55 #include "targ-vals.h"
  56 /* For xmalloc.  */
  57 #include "libiberty.h"
  58
  59 #ifdef HAVE_UNISTD_H
  60 #include <unistd.h>
  61 #endif
  62
  63 /* ??? sim_cb_printf should be cb_printf, but until the callback support is
  64    broken out of the simulator directory, these are here to not require
  65    sim-utils.h.  */
  66 void sim_cb_printf PARAMS ((host_callback *, const char *, ...));
  67 void sim_cb_eprintf PARAMS ((host_callback *, const char *, ...));
  68
  69 extern CB_TARGET_DEFS_MAP cb_init_syscall_map[];
  70 extern CB_TARGET_DEFS_MAP cb_init_errno_map[];
  71 extern CB_TARGET_DEFS_MAP cb_init_open_map[];
  72
  73 extern int system PARAMS ((const char *));
  74
  75 static int os_init PARAMS ((host_callback *));
  76 static int os_shutdown PARAMS ((host_callback *));
  77 static int os_unlink PARAMS ((host_callback *, const char *));
  78 static long os_time PARAMS ((host_callback *, long *));
  79 static int os_system PARAMS ((host_callback *, const char *));
  80 static int os_rename PARAMS ((host_callback *, const char *, const char *));
  81 static int os_write_stdout PARAMS ((host_callback *, const char *, int));
  82 static void os_flush_stdout PARAMS ((host_callback *));
  83 static int os_write_stderr PARAMS ((host_callback *, const char *, int));
  84 static void os_flush_stderr PARAMS ((host_callback *));
  85 static int os_write PARAMS ((host_callback *, int, const char *, int));
  86 static int os_read_stdin PARAMS ((host_callback *, char *, int));
  87 static int os_read PARAMS ((host_callback *, int, char *, int));
  88 static int os_open PARAMS ((host_callback *, const char *, int));
  89 static int os_lseek PARAMS ((host_callback *, int, long, int));
  90 static int os_isatty PARAMS ((host_callback *, int));
  91 static int os_get_errno PARAMS ((host_callback *));
  92 static int os_close PARAMS ((host_callback *, int));
  93 static void os_vprintf_filtered PARAMS ((host_callback *, const char *, va_list));
  94 static void os_evprintf_filtered PARAMS ((host_callback *, const char *, va_list));
  95 static void os_error PARAMS ((host_callback *, const char *, ...));
  96 static int fdmap PARAMS ((host_callback *, int));
  97 static int fdbad PARAMS ((host_callback *, int));
  98 static int wrap PARAMS ((host_callback *, int));
  99
 100 /* Set the callback copy of errno from what we see now.  */
 101
 102 static int
 103 wrap (p, val)
 104      host_callback *p;
 105      int val;
 106 {
 107   p->last_errno = errno;
 108   return val;
 109 }
 110
 111 /* Make sure the FD provided is ok.  If not, return non-zero
 112    and set errno. */
 113
 114 static int
 115 fdbad (p, fd)
 116      host_callback *p;
 117      int fd;
 118 {
 119   if (fd < 0 || fd > MAX_CALLBACK_FDS || p->fd_buddy[fd] < 0)
 120     {
 121       p->last_errno = EINVAL;
 122       return -1;
 123     }
 124   return 0;
 125 }
 126
 127 static int
 128 fdmap (p, fd)
 129      host_callback *p;
 130      int fd;
 131 {
 132   return p->fdmap[fd];
 133 }
 134
 135 static int
 136 os_close (p, fd)
 137      host_callback *p;
 138      int fd;
 139 {
 140   int result;
 141   int i, next;
 142
 143   result = fdbad (p, fd);
 144   if (result)
 145     return result;
 146   /* If this file descripter has one or more buddies (originals /
 147      duplicates from a dup), just remove it from the circular list.  */
 148   for (i = fd; (next = p->fd_buddy[i]) != fd; )
 149     i = next;
 150   if (fd != i)
 151     p->fd_buddy[i] = p->fd_buddy[fd];
 152   else
 153     {
 154       if (p->ispipe[fd])
 155         {
 156           int other = p->ispipe[fd];
 157           int reader, writer;
 158
 159           if (other > 0)
 160             {
 161               /* Closing the read side.  */
 162               reader = fd;
 163               writer = other;
 164             }
 165           else
 166             {
 167               /* Closing the write side.  */
 168               writer = fd;
 169               reader = -other;
 170             }
 171
 172           /* If there was data in the buffer, make a last "now empty"
 173              call, then deallocate data.  */
 174           if (p->pipe_buffer[writer].buffer != NULL)
 175             {
 176               (*p->pipe_empty) (p, reader, writer);
 177               free (p->pipe_buffer[writer].buffer);
 178               p->pipe_buffer[writer].buffer = NULL;
 179             }
 180
 181           /* Clear pipe data for this side.  */
 182           p->pipe_buffer[fd].size = 0;
 183           p->ispipe[fd] = 0;
 184
 185           /* If this was the first close, mark the other side as the
 186              only remaining side.  */
 187           if (fd != abs (other))
 188             p->ispipe[abs (other)] = -other;
 189           p->fd_buddy[fd] = -1;
 190           return 0;
 191         }
 192
 193       result = wrap (p, close (fdmap (p, fd)));
 194     }
 195   p->fd_buddy[fd] = -1;
 196
 197   return result;
 198 }
 199
 200
 201 /* taken from gdb/util.c:notice_quit() - should be in a library */
 202
 203
 204 #if defined(__GO32__) || defined (_MSC_VER)
 205 static int
 206 os_poll_quit (p)
 207      host_callback *p;
 208 {
 209 #if defined(__GO32__)
 210   int kbhit ();
 211   int getkey ();
 212   if (kbhit ())
 213     {
 214       int k = getkey ();
 215       if (k == 1)
 216         {
 217           return 1;
 218         }
 219       else if (k == 2)
 220         {
 221           return 1;
 222         }
 223       else
 224         {
 225           sim_cb_eprintf (p, "CTRL-A to quit, CTRL-B to quit harder\n");
 226         }
 227     }
 228 #endif
 229 #if defined (_MSC_VER)
 230   /* NB - this will not compile! */
 231   int k = win32pollquit();
 232   if (k == 1)
 233     return 1;
 234   else if (k == 2)
 235     return 1;
 236 #endif
 237   return 0;
 238 }
 239 #else
 240 #define os_poll_quit 0
 241 #endif /* defined(__GO32__) || defined(_MSC_VER) */
 242
 243 static int
 244 os_get_errno (p)
 245      host_callback *p;
 246 {
 247   return cb_host_to_target_errno (p, p->last_errno);
 248 }
 249
 250
 251 static int
 252 os_isatty (p, fd)
 253      host_callback *p;
 254      int fd;
 255 {
 256   int result;
 257
 258   result = fdbad (p, fd);
 259   if (result)
 260     return result;
 261   result = wrap (p, isatty (fdmap (p, fd)));
 262
 263   return result;
 264 }
 265
 266 static int
 267 os_lseek (p, fd, off, way)
 268      host_callback *p;
 269      int fd;
 270      long off;
 271      int way;
 272 {
 273   int result;
 274
 275   result = fdbad (p, fd);
 276   if (result)
 277     return result;
 278   result = lseek (fdmap (p, fd), off, way);
 279   return result;
 280 }
 281
 282 static int
 283 os_open (p, name, flags)
 284      host_callback *p;
 285      const char *name;
 286      int flags;
 287 {
 288   int i;
 289   for (i = 0; i < MAX_CALLBACK_FDS; i++)
 290     {
 291       if (p->fd_buddy[i] < 0)
 292         {
 293           int f = open (name, cb_target_to_host_open (p, flags), 0644);
 294           if (f < 0)
 295             {
 296               p->last_errno = errno;
 297               return f;
 298             }
 299           p->fd_buddy[i] = i;
 300           p->fdmap[i] = f;
 301           return i;
 302         }
 303     }
 304   p->last_errno = EMFILE;
 305   return -1;
 306 }
 307
 308 static int
 309 os_read (p, fd, buf, len)
 310      host_callback *p;
 311      int fd;
 312      char *buf;
 313      int len;
 314 {
 315   int result;
 316
 317   result = fdbad (p, fd);
 318   if (result)
 319     return result;
 320   if (p->ispipe[fd])
 321     {
 322       int writer = p->ispipe[fd];
 323
 324       /* Can't read from the write-end.  */
 325       if (writer < 0)
 326         {
 327           p->last_errno = EBADF;
 328           return -1;
 329         }
 330
 331       /* Nothing to read if nothing is written.  */
 332       if (p->pipe_buffer[writer].size == 0)
 333         return 0;
 334
 335       /* Truncate read request size to buffer size minus what's already
 336          read.  */
 337       if (len > p->pipe_buffer[writer].size - p->pipe_buffer[fd].size)
 338         len = p->pipe_buffer[writer].size - p->pipe_buffer[fd].size;
 339
 340       memcpy (buf, p->pipe_buffer[writer].buffer + p->pipe_buffer[fd].size,
 341               len);
 342
 343       /* Account for what we just read.  */
 344       p->pipe_buffer[fd].size += len;
 345
 346       /* If we've read everything, empty and deallocate the buffer and
 347          signal buffer-empty to client.  (This isn't expected to be a
 348          hot path in the simulator, so we don't hold on to the buffer.)  */
 349       if (p->pipe_buffer[fd].size == p->pipe_buffer[writer].size)
 350         {
 351           free (p->pipe_buffer[writer].buffer);
 352           p->pipe_buffer[writer].buffer = NULL;
 353           p->pipe_buffer[fd].size = 0;
 354           p->pipe_buffer[writer].size = 0;
 355           (*p->pipe_empty) (p, fd, writer);
 356         }
 357
 358       return len;
 359     }
 360
 361   result = wrap (p, read (fdmap (p, fd), buf, len));
 362   return result;
 363 }
 364
 365 static int
 366 os_read_stdin (p, buf, len)
 367      host_callback *p;
 368      char *buf;
 369      int len;
 370 {
 371   return wrap (p, read (0, buf, len));
 372 }
 373
 374 static int
 375 os_write (p, fd, buf, len)
 376      host_callback *p;
 377      int fd;
 378      const char *buf;
 379      int len;
 380 {
 381   int result;
 382   int real_fd;
 383
 384   result = fdbad (p, fd);
 385   if (result)
 386     return result;
 387
 388   if (p->ispipe[fd])
 389     {
 390       int reader = -p->ispipe[fd];
 391
 392       /* Can't write to the read-end.  */
 393       if (reader < 0)
 394         {
 395           p->last_errno = EBADF;
 396           return -1;
 397         }
 398
 399       /* Can't write to pipe with closed read end.
 400          FIXME: We should send a SIGPIPE.  */
 401       if (reader == fd)
 402         {
 403           p->last_errno = EPIPE;
 404           return -1;
 405         }
 406
 407       /* As a sanity-check, we bail out it the buffered contents is much
 408          larger than the size of the buffer on the host.  We don't want
 409          to run out of memory in the simulator due to a target program
 410          bug if we can help it.  Unfortunately, regarding the value that
 411          reaches the simulated program, it's no use returning *less*
 412          than the requested amount, because cb_syscall loops calling
 413          this function until the whole amount is done.  */
 414       if (p->pipe_buffer[fd].size + len > 10 * PIPE_BUF)
 415         {
 416           p->last_errno = EFBIG;
 417           return -1;
 418         }
 419
 420       p->pipe_buffer[fd].buffer
 421         = xrealloc (p->pipe_buffer[fd].buffer, p->pipe_buffer[fd].size + len);
 422       memcpy (p->pipe_buffer[fd].buffer + p->pipe_buffer[fd].size,
 423               buf, len);
 424       p->pipe_buffer[fd].size += len;
 425
 426       (*p->pipe_nonempty) (p, reader, fd);
 427       return len;
 428     }
 429
 430   real_fd = fdmap (p, fd);
 431   switch (real_fd)
 432     {
 433     default:
 434       result = wrap (p, write (real_fd, buf, len));
 435       break;
 436     case 1:
 437       result = p->write_stdout (p, buf, len);
 438       break;
 439     case 2:
 440       result = p->write_stderr (p, buf, len);
 441       break;
 442     }
 443   return result;
 444 }
 445
 446 static int
 447 os_write_stdout (p, buf, len)
 448      host_callback *p ATTRIBUTE_UNUSED;
 449      const char *buf;
 450      int len;
 451 {
 452   return fwrite (buf, 1, len, stdout);
 453 }
 454
 455 static void
 456 os_flush_stdout (p)
 457      host_callback *p ATTRIBUTE_UNUSED;
 458 {
 459   fflush (stdout);
 460 }
 461
 462 static int
 463 os_write_stderr (p, buf, len)
 464      host_callback *p ATTRIBUTE_UNUSED;
 465      const char *buf;
 466      int len;
 467 {
 468   return fwrite (buf, 1, len, stderr);
 469 }
 470
 471 static void
 472 os_flush_stderr (p)
 473      host_callback *p ATTRIBUTE_UNUSED;
 474 {
 475   fflush (stderr);
 476 }
 477
 478 static int
 479 os_rename (p, f1, f2)
 480      host_callback *p;
 481      const char *f1;
 482      const char *f2;
 483 {
 484   return wrap (p, rename (f1, f2));
 485 }
 486
 487
 488 static int
 489 os_system (p, s)
 490      host_callback *p;
 491      const char *s;
 492 {
 493   return wrap (p, system (s));
 494 }
 495
 496 static long
 497 os_time (p, t)
 498      host_callback *p;
 499      long *t;
 500 {
 501   return wrap (p, time (t));
 502 }
 503
 504
 505 static int
 506 os_unlink (p, f1)
 507      host_callback *p;
 508      const char *f1;
 509 {
 510   return wrap (p, unlink (f1));
 511 }
 512
 513 static int
 514 os_stat (p, file, buf)
 515      host_callback *p;
 516      const char *file;
 517      struct stat *buf;
 518 {
 519   /* ??? There is an issue of when to translate to the target layout.
 520      One could do that inside this function, or one could have the
 521      caller do it.  It's more flexible to let the caller do it, though
 522      I'm not sure the flexibility will ever be useful.  */
 523   return wrap (p, stat (file, buf));
 524 }
 525
 526 static int
 527 os_fstat (p, fd, buf)
 528      host_callback *p;
 529      int fd;
 530      struct stat *buf;
 531 {
 532   if (fdbad (p, fd))
 533     return -1;
 534
 535   if (p->ispipe[fd])
 536     {
 537       time_t t = (*p->time) (p, NULL);
 538
 539       /* We have to fake the struct stat contents, since the pipe is
 540          made up in the simulator.  */
 541       memset (buf, 0, sizeof (*buf));
 542
 543 #ifdef HAVE_STRUCT_STAT_ST_MODE
 544       buf->st_mode = S_IFIFO;
 545 #endif
 546
 547       /* If more accurate tracking than current-time is needed (for
 548          example, on GNU/Linux we get accurate numbers), the p->time
 549          callback (which may be something other than os_time) should
 550          happen for each read and write, and we'd need to keep track of
 551          atime, ctime and mtime.  */
 552 #ifdef HAVE_STRUCT_STAT_ST_ATIME
 553       buf->st_atime = t;
 554 #endif
 555 #ifdef HAVE_STRUCT_STAT_ST_CTIME
 556       buf->st_ctime = t;
 557 #endif
 558 #ifdef HAVE_STRUCT_STAT_ST_MTIME
 559       buf->st_mtime = t;
 560 #endif
 561       return 0;
 562     }
 563
 564   /* ??? There is an issue of when to translate to the target layout.
 565      One could do that inside this function, or one could have the
 566      caller do it.  It's more flexible to let the caller do it, though
 567      I'm not sure the flexibility will ever be useful.  */
 568   return wrap (p, fstat (fdmap (p, fd), buf));
 569 }
 570
 571 static int
 572 os_lstat (p, file, buf)
 573      host_callback *p;
 574      const char *file;
 575      struct stat *buf;
 576 {
 577   /* NOTE: hpn/2004-12-12: Same issue here as with os_fstat.  */
 578   return wrap (p, lstat (file, buf));
 579 }
 580
 581 static int
 582 os_ftruncate (p, fd, len)
 583      host_callback *p;
 584      int fd;
 585      long len;
 586 {
 587   int result;
 588
 589   result = fdbad (p, fd);
 590   if (p->ispipe[fd])
 591     {
 592       p->last_errno = EINVAL;
 593       return -1;
 594     }
 595   if (result)
 596     return result;
 597   result = wrap (p, ftruncate (fdmap (p, fd), len));
 598   return result;
 599 }
 600
 601 static int
 602 os_truncate (p, file, len)
 603      host_callback *p;
 604      const char *file;
 605      long len;
 606 {
 607   return wrap (p, truncate (file, len));
 608 }
 609
 610 static int
 611 os_pipe (p, filedes)
 612      host_callback *p;
 613      int *filedes;
 614 {
 615   int i;
 616
 617   /* We deliberately don't use fd 0.  It's probably stdin anyway.  */
 618   for (i = 1; i < MAX_CALLBACK_FDS; i++)
 619     {
 620       int j;
 621
 622       if (p->fd_buddy[i] < 0)
 623         for (j = i + 1; j < MAX_CALLBACK_FDS; j++)
 624           if (p->fd_buddy[j] < 0)
 625             {
 626               /* Found two free fd:s.  Set stat to allocated and mark
 627                  pipeness.  */
 628               p->fd_buddy[i] = i;
 629               p->fd_buddy[j] = j;
 630               p->ispipe[i] = j;
 631               p->ispipe[j] = -i;
 632               filedes[0] = i;
 633               filedes[1] = j;
 634
 635               /* Poison the FD map to make bugs apparent.  */
 636               p->fdmap[i] = -1;
 637               p->fdmap[j] = -1;
 638               return 0;
 639             }
 640     }
 641
 642   p->last_errno = EMFILE;
 643   return -1;
 644 }
 645
 646 /* Stub functions for pipe support.  They should always be overridden in
 647    targets using the pipe support, but that's up to the target.  */
 648
 649 /* Called when the simulator says that the pipe at (reader, writer) is
 650    now empty (so the writer should leave its waiting state).  */
 651
 652 static void
 653 os_pipe_empty (p, reader, writer)
 654      host_callback *p;
 655      int reader;
 656      int writer;
 657 {
 658 }
 659
 660 /* Called when the simulator says the pipe at (reader, writer) is now
 661    non-empty (so the writer should wait).  */
 662
 663 static void
 664 os_pipe_nonempty (p, reader, writer)
 665      host_callback *p;
 666      int reader;
 667      int writer;
 668 {
 669 }
 670
 671 static int
 672 os_shutdown (p)
 673      host_callback *p;
 674 {
 675   int i, next, j;
 676   for (i = 0; i < MAX_CALLBACK_FDS; i++)
 677     {
 678       int do_close = 1;
 679
 680       /* Zero out all pipe state.  Don't call callbacks for non-empty
 681          pipes; the target program has likely terminated at this point
 682          or we're called at initialization time.  */
 683       p->ispipe[i] = 0;
 684       p->pipe_buffer[i].size = 0;
 685       p->pipe_buffer[i].buffer = NULL;
 686
 687       next = p->fd_buddy[i];
 688       if (next < 0)
 689         continue;
 690       do
 691         {
 692           j = next;
 693           if (j == MAX_CALLBACK_FDS)
 694             do_close = 0;
 695           next = p->fd_buddy[j];
 696           p->fd_buddy[j] = -1;
 697           /* At the initial call of os_init, we got -1, 0, 0, 0, ...  */
 698           if (next < 0)
 699             {
 700               p->fd_buddy[i] = -1;
 701               do_close = 0;
 702               break;
 703             }
 704         }
 705       while (j != i);
 706       if (do_close)
 707         close (p->fdmap[i]);
 708     }
 709   return 1;
 710 }
 711
 712 static int
 713 os_init (p)
 714      host_callback *p;
 715 {
 716   int i;
 717
 718   os_shutdown (p);
 719   for (i = 0; i < 3; i++)
 720     {
 721       p->fdmap[i] = i;
 722       p->fd_buddy[i] = i - 1;
 723     }
 724   p->fd_buddy[0] = MAX_CALLBACK_FDS;
 725   p->fd_buddy[MAX_CALLBACK_FDS] = 2;
 726
 727   p->syscall_map = cb_init_syscall_map;
 728   p->errno_map = cb_init_errno_map;
 729   p->open_map = cb_init_open_map;
 730
 731   return 1;
 732 }
 733
 734 /* DEPRECATED */
 735
 736 /* VARARGS */
 737 static void
 738 #ifdef ANSI_PROTOTYPES
 739 os_printf_filtered (host_callback *p ATTRIBUTE_UNUSED, const char *format, ...)
 740 #else
 741 os_printf_filtered (p, va_alist)
 742      host_callback *p;
 743      va_dcl
 744 #endif
 745 {
 746   va_list args;
 747 #ifdef ANSI_PROTOTYPES
 748   va_start (args, format);
 749 #else
 750   char *format;
 751
 752   va_start (args);
 753   format = va_arg (args, char *);
 754 #endif
 755
 756   vfprintf (stdout, format, args);
 757   va_end (args);
 758 }
 759
 760 /* VARARGS */
 761 static void
 762 #ifdef ANSI_PROTOTYPES
 763 os_vprintf_filtered (host_callback *p ATTRIBUTE_UNUSED, const char *format, va_list args)
 764 #else
 765 os_vprintf_filtered (p, format, args)
 766      host_callback *p;
 767      const char *format;
 768      va_list args;
 769 #endif
 770 {
 771   vprintf (format, args);
 772 }
 773
 774 /* VARARGS */
 775 static void
 776 #ifdef ANSI_PROTOTYPES
 777 os_evprintf_filtered (host_callback *p ATTRIBUTE_UNUSED, const char *format, va_list args)
 778 #else
 779 os_evprintf_filtered (p, format, args)
 780      host_callback *p;
 781      const char *format;
 782      va_list args;
 783 #endif
 784 {
 785   vfprintf (stderr, format, args);
 786 }
 787
 788 /* VARARGS */
 789 static void
 790 #ifdef ANSI_PROTOTYPES
 791 os_error (host_callback *p ATTRIBUTE_UNUSED, const char *format, ...)
 792 #else
 793 os_error (p, va_alist)
 794      host_callback *p;
 795      va_dcl
 796 #endif
 797 {
 798   va_list args;
 799 #ifdef ANSI_PROTOTYPES
 800   va_start (args, format);
 801 #else
 802   char *format;
 803
 804   va_start (args);
 805   format = va_arg (args, char *);
 806 #endif
 807
 808   vfprintf (stderr, format, args);
 809   fprintf (stderr, "\n");
 810
 811   va_end (args);
 812   exit (1);
 813 }
 814
 815 host_callback default_callback =
 816 {
 817   os_close,
 818   os_get_errno,
 819   os_isatty,
 820   os_lseek,
 821   os_open,
 822   os_read,
 823   os_read_stdin,
 824   os_rename,
 825   os_system,
 826   os_time,
 827   os_unlink,
 828   os_write,
 829   os_write_stdout,
 830   os_flush_stdout,
 831   os_write_stderr,
 832   os_flush_stderr,
 833
 834   os_stat,
 835   os_fstat,
 836   os_lstat,
 837
 838   os_ftruncate,
 839   os_truncate,
 840
 841   os_pipe,
 842   os_pipe_empty,
 843   os_pipe_nonempty,
 844
 845   os_poll_quit,
 846
 847   os_shutdown,
 848   os_init,
 849
 850   os_printf_filtered,  /* deprecated */
 851
 852   os_vprintf_filtered,
 853   os_evprintf_filtered,
 854   os_error,
 855
 856   0,            /* last errno */
 857
 858   { 0, },       /* fdmap */
 859   { -1, },      /* fd_buddy */
 860   { 0, },       /* ispipe */
 861   { { 0, 0 }, }, /* pipe_buffer */
 862
 863   0, /* syscall_map */
 864   0, /* errno_map */
 865   0, /* open_map */
 866   0, /* signal_map */
 867   0, /* stat_map */
 868
 869   /* Defaults expected to be overridden at initialization, where needed.  */
 870   BFD_ENDIAN_UNKNOWN, /* target_endian */
 871   4, /* target_sizeof_int */
 872
 873   HOST_CALLBACK_MAGIC,
 874 };
 875 \f
 876 /* Read in a file describing the target's system call values.
 877    E.g. maybe someone will want to use something other than newlib.
 878    This assumes that the basic system call recognition and value passing/
 879    returning is supported.  So maybe some coding/recompilation will be
 880    necessary, but not as much.
 881
 882    If an error occurs, the existing mapping is not changed.  */
 883
 884 CB_RC
 885 cb_read_target_syscall_maps (cb, file)
 886      host_callback *cb;
 887      const char *file;
 888 {
 889   CB_TARGET_DEFS_MAP *syscall_map, *errno_map, *open_map, *signal_map;
 890   const char *stat_map;
 891   FILE *f;
 892
 893   if ((f = fopen (file, "r")) == NULL)
 894     return CB_RC_ACCESS;
 895
 896   /* ... read in and parse file ... */
 897
 898   fclose (f);
 899   return CB_RC_NO_MEM; /* FIXME:wip */
 900
 901   /* Free storage allocated for any existing maps.  */
 902   if (cb->syscall_map)
 903     free (cb->syscall_map);
 904   if (cb->errno_map)
 905     free (cb->errno_map);
 906   if (cb->open_map)
 907     free (cb->open_map);
 908   if (cb->signal_map)
 909     free (cb->signal_map);
 910   if (cb->stat_map)
 911     free ((PTR) cb->stat_map);
 912
 913   cb->syscall_map = syscall_map;
 914   cb->errno_map = errno_map;
 915   cb->open_map = open_map;
 916   cb->signal_map = signal_map;
 917   cb->stat_map = stat_map;
 918
 919   return CB_RC_OK;
 920 }
 921
 922 /* Translate the target's version of a syscall number to the host's.
 923    This isn't actually the host's version, rather a canonical form.
 924    ??? Perhaps this should be renamed to ..._canon_syscall.  */
 925
 926 int
 927 cb_target_to_host_syscall (cb, target_val)
 928      host_callback *cb;
 929      int target_val;
 930 {
 931   CB_TARGET_DEFS_MAP *m;
 932
 933   for (m = &cb->syscall_map[0]; m->target_val != -1; ++m)
 934     if (m->target_val == target_val)
 935       return m->host_val;
 936
 937   return -1;
 938 }
 939
 940 /* FIXME: sort tables if large.
 941    Alternatively, an obvious improvement for errno conversion is
 942    to machine generate a function with a large switch().  */
 943
 944 /* Translate the host's version of errno to the target's.  */
 945
 946 int
 947 cb_host_to_target_errno (cb, host_val)
 948      host_callback *cb;
 949      int host_val;
 950 {
 951   CB_TARGET_DEFS_MAP *m;
 952
 953   for (m = &cb->errno_map[0]; m->host_val; ++m)
 954     if (m->host_val == host_val)
 955       return m->target_val;
 956
 957   /* ??? Which error to return in this case is up for grabs.
 958      Note that some missing values may have standard alternatives.
 959      For now return 0 and require caller to deal with it.  */
 960   return 0;
 961 }
 962
 963 /* Given a set of target bitmasks for the open system call,
 964    return the host equivalent.
 965    Mapping open flag values is best done by looping so there's no need
 966    to machine generate this function.  */
 967
 968 int
 969 cb_target_to_host_open (cb, target_val)
 970      host_callback *cb;
 971      int target_val;
 972 {
 973   int host_val = 0;
 974   CB_TARGET_DEFS_MAP *m;
 975
 976   for (m = &cb->open_map[0]; m->host_val != -1; ++m)
 977     {
 978       switch (m->target_val)
 979         {
 980           /* O_RDONLY can be (and usually is) 0 which needs to be treated
 981              specially.  */
 982         case TARGET_O_RDONLY :
 983         case TARGET_O_WRONLY :
 984         case TARGET_O_RDWR :
 985           if ((target_val & (TARGET_O_RDONLY | TARGET_O_WRONLY | TARGET_O_RDWR))
 986               == m->target_val)
 987             host_val |= m->host_val;
 988           /* Handle the host/target differentiating between binary and
 989              text mode.  Only one case is of importance */
 990 #if ! defined (TARGET_O_BINARY) && defined (O_BINARY)
 991           host_val |= O_BINARY;
 992 #endif
 993           break;
 994         default :
 995           if ((m->target_val & target_val) == m->target_val)
 996             host_val |= m->host_val;
 997           break;
 998         }
 999     }
1000
1001   return host_val;
1002 }
1003
1004 /* Utility for e.g. cb_host_to_target_stat to store values in the target's
1005    stat struct.  */
1006
1007 void
1008 cb_store_target_endian (cb, p, size, val)
1009      host_callback *cb;
1010      char *p;
1011      int size;
1012      long val; /* ??? must be as big as target word size */
1013 {
1014   if (cb->target_endian == BFD_ENDIAN_BIG)
1015     {
1016       p += size;
1017       while (size-- > 0)
1018         {
1019           *--p = val;
1020           val >>= 8;
1021         }
1022     }
1023   else
1024     {
1025       while (size-- > 0)
1026         {
1027           *p++ = val;
1028           val >>= 8;
1029         }
1030     }
1031 }
1032
1033 /* Translate a host's stat struct into a target's.
1034    If HS is NULL, just compute the length of the buffer required,
1035    TS is ignored.
1036
1037    The result is the size of the target's stat struct,
1038    or zero if an error occurred during the translation.  */
1039
1040 int
1041 cb_host_to_target_stat (cb, hs, ts)
1042      host_callback *cb;
1043      const struct stat *hs;
1044      PTR ts;
1045 {
1046   const char *m = cb->stat_map;
1047   char *p;
1048
1049   if (hs == NULL)
1050     ts = NULL;
1051   p = ts;
1052
1053   while (m)
1054     {
1055       char *q = strchr (m, ',');
1056       int size;
1057
1058       /* FIXME: Use sscanf? */
1059       if (q == NULL)
1060         {
1061           /* FIXME: print error message */
1062           return 0;
1063         }
1064       size = atoi (q + 1);
1065       if (size == 0)
1066         {
1067           /* FIXME: print error message */
1068           return 0;
1069         }
1070
1071       if (hs != NULL)
1072         {
1073           if (0)
1074             ;
1075           /* Defined here to avoid emacs indigestion on a lone "else".  */
1076 #undef ST_x
1077 #define ST_x(FLD)                                       \
1078           else if (strncmp (m, #FLD, q - m) == 0)       \
1079             cb_store_target_endian (cb, p, size, hs->FLD)
1080
1081 #ifdef HAVE_STRUCT_STAT_ST_DEV
1082           ST_x (st_dev);
1083 #endif
1084 #ifdef HAVE_STRUCT_STAT_ST_INO
1085           ST_x (st_ino);
1086 #endif
1087 #ifdef HAVE_STRUCT_STAT_ST_MODE
1088           ST_x (st_mode);
1089 #endif
1090 #ifdef HAVE_STRUCT_STAT_ST_NLINK
1091           ST_x (st_nlink);
1092 #endif
1093 #ifdef HAVE_STRUCT_STAT_ST_UID
1094           ST_x (st_uid);
1095 #endif
1096 #ifdef HAVE_STRUCT_STAT_ST_GID
1097           ST_x (st_gid);
1098 #endif
1099 #ifdef HAVE_STRUCT_STAT_ST_RDEV
1100           ST_x (st_rdev);
1101 #endif
1102 #ifdef HAVE_STRUCT_STAT_ST_SIZE
1103           ST_x (st_size);
1104 #endif
1105 #ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
1106           ST_x (st_blksize);
1107 #endif
1108 #ifdef HAVE_STRUCT_STAT_ST_BLOCKS
1109           ST_x (st_blocks);
1110 #endif
1111 #ifdef HAVE_STRUCT_STAT_ST_ATIME
1112           ST_x (st_atime);
1113 #endif
1114 #ifdef HAVE_STRUCT_STAT_ST_MTIME
1115           ST_x (st_mtime);
1116 #endif
1117 #ifdef HAVE_STRUCT_STAT_ST_CTIME
1118           ST_x (st_ctime);
1119 #endif
1120 #undef ST_x
1121           /* FIXME:wip */
1122           else
1123             /* Unsupported field, store 0.  */
1124             cb_store_target_endian (cb, p, size, 0);
1125         }
1126
1127       p += size;
1128       m = strchr (q, ':');
1129       if (m)
1130         ++m;
1131     }
1132
1133   return p - (char *) ts;
1134 }
1135 \f
1136 /* Cover functions to the vfprintf callbacks.
1137
1138    ??? If one thinks of the callbacks as a subsystem onto itself [or part of
1139    a larger "remote target subsystem"] with a well defined interface, then
1140    one would think that the subsystem would provide these.  However, until
1141    one is allowed to create such a subsystem (with its own source tree
1142    independent of any particular user), such a critter can't exist.  Thus
1143    these functions are here for the time being.  */
1144
1145 void
1146 sim_cb_printf (host_callback *p, const char *fmt, ...)
1147 {
1148   va_list ap;
1149
1150   va_start (ap, fmt);
1151   p->vprintf_filtered (p, fmt, ap);
1152   va_end (ap);
1153 }
1154
1155 void
1156 sim_cb_eprintf (host_callback *p, const char *fmt, ...)
1157 {
1158   va_list ap;
1159
1160   va_start (ap, fmt);
1161   p->evprintf_filtered (p, fmt, ap);
1162   va_end (ap);
1163 }