compiler/posixc/__fdesc.c

   1 /*
   2     Copyright © 1995-2014, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     File descriptor handling internals.
   6 */
   7
   8 #include LC_LIBDEFS_FILE
   9
  10 #include <string.h>
  11 #include <fcntl.h>
  12 #include <stdlib.h>
  13 #include <unistd.h>
  14 #include <errno.h>
  15
  16 #define DEBUG 0
  17
  18 #include <proto/exec.h>
  19 #include <proto/dos.h>
  20 #include <exec/memory.h>
  21 #include <exec/semaphores.h>
  22 #include <dos/dos.h>
  23 #include <dos/stdio.h>
  24 #include <aros/symbolsets.h>
  25 #include <aros/debug.h>
  26 #include "__fdesc.h"
  27 #include "__upath.h"
  28
  29 /* TODO: Add locking to make filedesc usage thread safe
  30    Using vfork()+exec*() filedescriptors may be shared between different
  31    tasks. Only one DOS file handle is used between shared file descriptors.
  32    DOS file handles are not thread safe so we should add it here to make it
  33    thread safe.
  34    Possible implementation should look carefully at performance impact.
  35 */
  36
  37 void __getfdarray(APTR *arrayptr, int *slotsptr)
  38 {
  39     struct PosixCIntBase *PosixCBase =
  40         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
  41
  42     *arrayptr = PosixCBase->fd_array;
  43     *slotsptr = PosixCBase->fd_slots;
  44 }
  45
  46 void __setfdarray(APTR array, int slots)
  47 {
  48     struct PosixCIntBase *PosixCBase =
  49         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
  50
  51     PosixCBase->fd_array = array;
  52     PosixCBase->fd_slots = slots;
  53 }
  54
  55 void __setfdarraybase(struct PosixCIntBase *PosixCBase2)
  56 {
  57     struct PosixCIntBase *PosixCBase =
  58         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
  59
  60     PosixCBase->fd_array = PosixCBase2->fd_array;
  61     PosixCBase->fd_slots = PosixCBase2->fd_slots;
  62 }
  63
  64 int __getfdslots(void)
  65 {
  66     struct PosixCIntBase *PosixCBase =
  67         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
  68
  69     return PosixCBase->fd_slots;
  70 }
  71
  72 fdesc *__getfdesc(register int fd)
  73 {
  74     struct PosixCIntBase *PosixCBase =
  75         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
  76
  77     return ((PosixCBase->fd_slots>fd) && (fd>=0))?PosixCBase->fd_array[fd]:NULL;
  78 }
  79
  80 void __setfdesc(register int fd, fdesc *desc)
  81 {
  82     struct PosixCIntBase *PosixCBase =
  83         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
  84
  85     /* FIXME: Check if fd is in valid range... */
  86     PosixCBase->fd_array[fd] = desc;
  87 }
  88
  89 int __getfirstfd(register int startfd)
  90 {
  91     struct PosixCIntBase *PosixCBase =
  92         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
  93
  94     /* FIXME: Check if fd is in valid range... */
  95     for (
  96         ;
  97         startfd < PosixCBase->fd_slots && PosixCBase->fd_array[startfd];
  98         startfd++
  99     );
 100
 101     return startfd;
 102 }
 103
 104 int __getfdslot(int wanted_fd)
 105 {
 106     struct PosixCIntBase *PosixCBase =
 107         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
 108
 109     if (wanted_fd>=PosixCBase->fd_slots)
 110     {
 111         void *tmp;
 112
 113         tmp = AllocPooled(PosixCBase->internalpool, (wanted_fd+1)*sizeof(fdesc *));
 114
 115         if (!tmp) return -1;
 116
 117         if (PosixCBase->fd_array)
 118         {
 119             size_t size = PosixCBase->fd_slots*sizeof(fdesc *);
 120             CopyMem(PosixCBase->fd_array, tmp, size);
 121             FreePooled(PosixCBase->internalpool, PosixCBase->fd_array, size);
 122         }
 123
 124         PosixCBase->fd_array = tmp;
 125         PosixCBase->fd_slots = wanted_fd+1;
 126     }
 127     else if (wanted_fd < 0)
 128     {
 129         errno = EINVAL;
 130         return -1;
 131     }
 132     else if (PosixCBase->fd_array[wanted_fd])
 133     {
 134         close(wanted_fd);
 135     }
 136
 137     return wanted_fd;
 138 }
 139
 140 LONG __oflags2amode(int flags)
 141 {
 142     LONG openmode = -1;
 143
 144     /* filter out invalid modes */
 145     switch (flags & (O_CREAT|O_TRUNC|O_EXCL))
 146     {
 147         case O_EXCL:
 148         case O_EXCL|O_TRUNC:
 149             return -1;
 150     }
 151
 152     /* Sorted in 'trumping' order. Ie if
 153      * O_WRITE is on, that overrides O_READ.
 154      * Similarly, O_CREAT overrides O_WRITE.
 155      */
 156     if (flags & O_RDONLY)   openmode = MODE_OLDFILE;
 157     if (flags & O_WRONLY)   openmode = MODE_OLDFILE;
 158     if (flags & O_RDWR)     openmode = MODE_OLDFILE;
 159     if (flags & O_READ)     openmode = MODE_OLDFILE;
 160     if (flags & O_WRITE)    openmode = MODE_READWRITE;
 161     if (flags & O_CREAT)    /* Handled later */;
 162     if (flags & O_APPEND)   /* Handled later */;
 163     if (flags & O_TRUNC)    /* Handled later */;
 164     if (flags & O_EXEC)     /* Ignored */;
 165     if (flags & O_NONBLOCK) /* Ignored */;
 166
 167     return openmode;
 168 }
 169
 170 int __open(int wanted_fd, const char *pathname, int flags, int mode)
 171 {
 172     struct PosixCIntBase *PosixCBase =
 173         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
 174
 175     BPTR fh = BNULL, lock = BNULL;
 176     fdesc *currdesc = NULL;
 177     fcb *cblock = NULL;
 178     struct FileInfoBlock *fib = NULL;
 179     LONG  openmode = __oflags2amode(flags);
 180
 181     if (PosixCBase->doupath && pathname[0] == '\0')
 182     {
 183         /* On *nix "" is not really a valid file name.  */
 184         errno = ENOENT;
 185         return -1;
 186     }
 187
 188     pathname = __path_u2a(pathname);
 189     if (!pathname) return -1;
 190
 191     D(bug("__open: entering, wanted fd = %d, path = %s, flags = %d, mode = %d\n", wanted_fd, pathname, flags, mode));
 192
 193     if (openmode == -1)
 194     {
 195         errno = EINVAL;
 196         D(bug( "__open: exiting with error EINVAL\n"));
 197         return -1;
 198     }
 199
 200     cblock = AllocVec(sizeof(fcb), MEMF_ANY | MEMF_CLEAR);
 201     if (!cblock) { D(bug("__open: no memory [1]\n")); goto err; }
 202     currdesc = __alloc_fdesc();
 203     if (!currdesc) { D(bug("__open: no memory [2]\n")); goto err; }
 204     currdesc->fdflags = 0;
 205     currdesc->fcb = cblock;
 206
 207     wanted_fd = __getfdslot(wanted_fd);
 208     if (wanted_fd == -1) { D(bug("__open: no free fd\n")); goto err; }
 209
 210     /*
 211      * In case of file system, test existance of file. Non-file system handlers (i.e CON:)
 212      * support opening a file while not supporting locking.
 213      */
 214     if(IsFileSystem(pathname) == DOSTRUE)
 215     {
 216         lock = Lock((char *)pathname, SHARED_LOCK);
 217         if (!lock)
 218         {
 219             if (IoErr() == ERROR_OBJECT_WRONG_TYPE)
 220             {
 221                 /*
 222                    Needed for sfs file system which reports this error number on a
 223                    Lock aaa/bbb/ccc with bbb being a file instead of a directory.
 224                 */
 225                 errno = ENOTDIR;
 226                 goto err;
 227             }
 228
 229             if
 230             (
 231                 (IoErr() != ERROR_OBJECT_NOT_FOUND) ||
 232                 /* If the file doesn't exist and the flag O_CREAT is not set return an error */
 233                 (IoErr() == ERROR_OBJECT_NOT_FOUND && !(flags & O_CREAT))
 234             )
 235             {
 236                 errno = __stdc_ioerr2errno(IoErr());
 237                 goto err;
 238             }
 239         }
 240         else
 241         {
 242             /* If the file exists, but O_EXCL is set, then return an error */
 243             if (flags & O_EXCL)
 244             {
 245                 errno = EEXIST;
 246                 goto err;
 247             }
 248
 249             fib = AllocDosObject(DOS_FIB, NULL);
 250             if (!fib)
 251             {
 252                errno = __stdc_ioerr2errno(IoErr());
 253                goto err;
 254             }
 255
 256             if (!Examine(lock, fib))
 257             {
 258                 /*
 259                     The filesystem in which the file resides doesn't support
 260                     the EXAMINE action. It might be broken or might also not
 261                     be a filesystem at all. So let's assume the file is not a
 262                     diretory.
 263                */
 264                fib->fib_DirEntryType = 0;
 265             }
 266
 267             /* FIXME: implement softlink handling */
 268
 269             /* Check if it's a directory or a softlink.
 270                Softlinks are not handled yet, though */
 271             if (fib->fib_DirEntryType > 0)
 272             {
 273                 /* A directory cannot be opened for writing */
 274                 if (openmode != MODE_OLDFILE)
 275                 {
 276                     errno = EISDIR;
 277                     goto err;
 278                 }
 279
 280                 fh = lock;
 281                 FreeDosObject(DOS_FIB, fib);
 282                 currdesc->fcb->privflags |= _FCB_ISDIR;
 283
 284                 goto success;
 285             }
 286             FreeDosObject(DOS_FIB, fib);
 287             fib = NULL;
 288         }
 289     }
 290
 291     /* the file exists and it's not a directory or the file doesn't exist */
 292
 293     if (lock)
 294     {
 295         UnLock(lock);
 296         lock = BNULL;
 297     }
 298     else
 299     {
 300         /* Handle O_CREAT (creates the file only if it does not exist) */
 301         if (flags & O_CREAT)
 302         {
 303             BPTR tmp = Open((char *)pathname, MODE_NEWFILE);
 304             if (tmp != BNULL) Close(tmp);
 305             /* File is closed as O_CREAT does not define access
 306              * mode. This is handled by R/W modes.
 307              */
 308         }
 309     }
 310
 311     if (!(fh = Open ((char *)pathname, openmode)) )
 312     {
 313         ULONG ioerr = IoErr();
 314         D(bug("__open: Open ioerr=%d\n", ioerr));
 315         errno = __stdc_ioerr2errno(ioerr);
 316         goto err;
 317     }
 318
 319     /* Allow opening NIL: (/dev/null) regardless of additional flags/modes */
 320     if (!strcasecmp(pathname, "NIL:"))
 321         goto success;
 322
 323     /* Handle O_TRUNC */
 324     if((flags & O_TRUNC) && (flags & (O_RDWR | O_WRONLY)))
 325     {
 326         if(SetFileSize(fh, 0, OFFSET_BEGINNING) != 0)
 327         {
 328             ULONG ioerr = IoErr();
 329             /* Ignore error if ACTION_SET_FILE_SIZE is not implemented */
 330             if(ioerr != ERROR_NOT_IMPLEMENTED &&
 331                ioerr != ERROR_ACTION_NOT_KNOWN)
 332             {
 333                 D(bug("__open: SetFileSize ioerr=%d\n", ioerr));
 334                 errno = __stdc_ioerr2errno(ioerr);
 335                 goto err;
 336             }
 337         }
 338     }
 339
 340     /* Handle O_APPEND */
 341     if((flags & O_APPEND) && (flags & (O_RDWR | O_WRONLY)))
 342     {
 343         if(Seek(fh, 0, OFFSET_END) != 0) {
 344             errno = __stdc_ioerr2errno(IoErr());
 345             goto err;
 346         }
 347     }
 348
 349
 350 success:
 351     currdesc->fcb->handle    = fh;
 352     currdesc->fcb->flags     = flags;
 353     currdesc->fcb->opencount = 1;
 354
 355     __setfdesc(wanted_fd, currdesc);
 356
 357     D(bug("__open: exiting fd=%d\n", wanted_fd));
 358
 359     return wanted_fd;
 360
 361 err:
 362     if (fib) FreeDosObject(DOS_FIB, fib);
 363     FreeVec(cblock);
 364     if (currdesc) __free_fdesc(currdesc);
 365     if (fh && fh != lock) Close(fh);
 366     if (lock) UnLock(lock);
 367
 368     D(bug("__open: exiting with error %d\n", errno ));
 369
 370     return -1;
 371 }
 372
 373 fdesc *__alloc_fdesc(void)
 374 {
 375     struct PosixCIntBase *PosixCBase =
 376         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
 377     fdesc * desc;
 378
 379     desc = AllocPooled(PosixCBase->internalpool, sizeof(fdesc));
 380
 381     D(bug("Allocated fdesc %x from %x pool\n", desc, PosixCBase->internalpool));
 382
 383     return desc;
 384 }
 385
 386 void __free_fdesc(fdesc *desc)
 387 {
 388     struct PosixCIntBase *PosixCBase =
 389         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
 390
 391     D(bug("Freeing fdesc %x from %x pool\n", desc, PosixCBase->internalpool));
 392     FreePooled(PosixCBase->internalpool, desc, sizeof(fdesc));
 393 }
 394
 395 static void stderrlogic(struct Process *me, fcb *fcb)
 396 {
 397     if ((fcb->handle != BNULL) && !(fcb->privflags & _FCB_DONTCLOSE_FH))
 398         Close(fcb->handle);
 399     if (me->pr_CES != BNULL)
 400     {
 401         fcb->handle = me->pr_CES;
 402         fcb->privflags |= _FCB_DONTCLOSE_FH;
 403     }
 404     else
 405     {
 406         fcb->handle = Open("NIL:", MODE_OLDFILE);
 407         fcb->privflags &= ~_FCB_DONTCLOSE_FH;
 408     }
 409     /* stderr is expected to be unbuffered for POSIX. */
 410     SetVBuf(fcb->handle, NULL, BUF_NONE, -1);
 411 }
 412
 413 /* FIXME: perhaps this has to be handled in a different way...  */
 414 int __init_stdfiles(struct PosixCIntBase *PosixCBase)
 415 {
 416     struct Process *me;
 417     fcb *infcb = NULL, *outfcb = NULL, *errfcb = NULL;
 418     fdesc *indesc=NULL, *outdesc=NULL, *errdesc=NULL;
 419     int res = __getfdslot(2);
 420
 421     if
 422     (
 423         res == -1                           ||
 424         !(infcb  = AllocVec(sizeof(fcb), MEMF_ANY | MEMF_CLEAR)) ||
 425         !(indesc  = __alloc_fdesc()) ||
 426         !(outfcb = AllocVec(sizeof(fcb), MEMF_ANY | MEMF_CLEAR)) ||
 427         !(outdesc = __alloc_fdesc()) ||
 428         !(errfcb = AllocVec(sizeof(fcb), MEMF_ANY | MEMF_CLEAR)) ||
 429         !(errdesc = __alloc_fdesc())
 430     )
 431     {
 432         FreeVec(infcb);
 433         if(indesc)
 434             __free_fdesc(indesc);
 435         FreeVec(outfcb);
 436         if(outdesc)
 437             __free_fdesc(outdesc);
 438         FreeVec(errfcb);
 439         if(errdesc)
 440             __free_fdesc(errdesc);
 441         SetIoErr(ERROR_NO_FREE_STORE);
 442         return 0;
 443     }
 444
 445     me = (struct Process *)FindTask (NULL);
 446
 447     infcb->handle = Input();
 448     infcb->flags  = O_RDONLY;
 449     infcb->opencount = 1;
 450     /* Remove (remaining) command line args on first read */
 451     infcb->privflags = _FCB_FLUSHONREAD;
 452     infcb->privflags |= _FCB_DONTCLOSE_FH;
 453     indesc->fcb = infcb;
 454     indesc->fdflags = 0;
 455     D(bug("[__init_stdfiles]Input(): %p, infcb->handle: %p\n",
 456           BADDR(Input()), BADDR(infcb->handle)
 457     ));
 458
 459     outfcb->handle = Output();
 460     outfcb->flags = O_WRONLY | O_APPEND;
 461     outfcb->opencount = 1;
 462     outfcb->privflags |= _FCB_DONTCLOSE_FH;
 463     outdesc->fcb = outfcb;
 464     outdesc->fdflags = 0;
 465     D(bug("[__init_stdfiles]Output(): %p, outfcb->handle: %p\n",
 466           BADDR(Output()), BADDR(outfcb->handle)
 467     ));
 468
 469     errfcb->privflags = 0;
 470     stderrlogic(me, errfcb);
 471     errfcb->flags = O_WRONLY | O_APPEND;
 472     errfcb->opencount = 1;
 473     errdesc->fcb = errfcb;
 474     errdesc->fdflags = 0;
 475     D(bug("[__init_stdfiles]me->pr_CES: %p, errfcb->handle: %p\n",
 476           BADDR(me->pr_CES), BADDR(errfcb->handle)
 477     ));
 478
 479     PosixCBase->fd_array[STDIN_FILENO]  = indesc;
 480     PosixCBase->fd_array[STDOUT_FILENO] = outdesc;
 481     PosixCBase->fd_array[STDERR_FILENO] = errdesc;
 482
 483     return 1;
 484 }
 485
 486 static int __copy_fdarray(fdesc **__src_fd_array, int fd_slots)
 487 {
 488     struct PosixCIntBase *PosixCBase =
 489         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
 490     int i;
 491
 492     for(i = fd_slots - 1; i >= 0; i--)
 493     {
 494         if(__src_fd_array[i])
 495         {
 496             if(__getfdslot(i) != i)
 497                 return 0;
 498
 499             if((PosixCBase->fd_array[i] = __alloc_fdesc()) == NULL)
 500                 return 0;
 501
 502             PosixCBase->fd_array[i]->fdflags = __src_fd_array[i]->fdflags;
 503             PosixCBase->fd_array[i]->fcb = __src_fd_array[i]->fcb;
 504             PosixCBase->fd_array[i]->fcb->opencount++;
 505         }
 506     }
 507
 508     return 1;
 509 }
 510
 511 int __init_fd(struct PosixCIntBase *PosixCBase)
 512 {
 513     struct PosixCIntBase *pPosixCBase =
 514         (struct PosixCIntBase *)__GM_GetBaseParent(PosixCBase);
 515
 516     D(bug("Found parent PosixCBase %p with flags 0x%x\n",
 517           pPosixCBase, pPosixCBase ? pPosixCBase->flags : 0
 518     ));
 519
 520     if (pPosixCBase && (pPosixCBase->flags & (VFORK_PARENT | EXEC_PARENT)))
 521     {
 522         /* VFORK_PARENT use case - child manipulates file descriptors prior to calling exec* */
 523         int res = __copy_fdarray(pPosixCBase->fd_array, pPosixCBase->fd_slots);
 524
 525         if (pPosixCBase->flags & EXEC_PARENT)
 526             /* EXEC_PARENT called through RunCommand which injected parameters to Input() */
 527             PosixCBase->fd_array[STDIN_FILENO]->fcb->privflags |= _FCB_FLUSHONREAD;
 528
 529         return res;
 530     }
 531     else
 532         return __init_stdfiles(PosixCBase);
 533 }
 534
 535 void __exit_fd(struct PosixCIntBase *PosixCBase)
 536 {
 537     int i = PosixCBase->fd_slots;
 538     while (i)
 539     {
 540         if (PosixCBase->fd_array[--i])
 541             close(i);
 542     }
 543 }
 544
 545 void __close_on_exec_fdescs(void)
 546 {
 547     struct PosixCIntBase *PosixCBase =
 548         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
 549     int i;
 550     fdesc *fd;
 551
 552     for (i = PosixCBase->fd_slots - 1; i >= 0; i--)
 553     {
 554         if ((fd = __getfdesc(i)) != NULL)
 555         {
 556             D(bug("__close_fdesc_on_exec: checking fd %d\n", i));
 557             if (fd->fdflags & FD_CLOEXEC)
 558             {
 559                 D(bug("__close_fdesc_on_exec: closing fd %d\n", i));
 560                 close(i);
 561             }
 562         }
 563     }
 564 }
 565
 566 #include <stdio.h>
 567
 568 void __updatestdio(void)
 569 {
 570     struct PosixCIntBase *PosixCBase =
 571         (struct PosixCIntBase *)__aros_getbase_PosixCBase();
 572     struct Process *me;
 573     fcb *fcb = NULL;
 574
 575     me = (struct Process *)FindTask(NULL);
 576
 577     fflush(((struct PosixCBase *)PosixCBase)->_stdin);
 578     fflush(((struct PosixCBase *)PosixCBase)->_stdout);
 579     fflush(((struct PosixCBase *)PosixCBase)->_stderr);
 580
 581     fcb = PosixCBase->fd_array[STDIN_FILENO]->fcb;
 582     fcb->handle = Input();
 583
 584     fcb = PosixCBase->fd_array[STDOUT_FILENO]->fcb;
 585     fcb->handle = Output();
 586
 587     fcb = PosixCBase->fd_array[STDERR_FILENO]->fcb;
 588     stderrlogic(me, fcb);
 589 }
 590
 591 ADD2OPENLIB(__init_fd, 2);
 592 ADD2CLOSELIB(__exit_fd, 2);
 593