server/file.c

   1 /*
   2  * Server-side file management
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  */
   6
   7 #include "config.h"
   8
   9 #include <assert.h>
  10 #include <fcntl.h>
  11 #include <stdio.h>
  12 #include <string.h>
  13 #include <stdlib.h>
  14 #include <errno.h>
  15 #ifdef HAVE_SYS_ERRNO_H
  16 #include <sys/errno.h>
  17 #endif
  18 #include <sys/stat.h>
  19 #include <sys/time.h>
  20 #include <sys/types.h>
  21 #include <time.h>
  22 #include <unistd.h>
  23 #include <utime.h>
  24
  25 #include "winerror.h"
  26 #include "winbase.h"
  27
  28 #include "handle.h"
  29 #include "thread.h"
  30 #include "request.h"
  31
  32 struct file
  33 {
  34     struct object       obj;        /* object header */
  35     struct file        *next;       /* next file in hashing list */
  36     char               *name;       /* file name */
  37     unsigned int        access;     /* file access (GENERIC_READ/WRITE) */
  38     unsigned int        flags;      /* flags (FILE_FLAG_*) */
  39     unsigned int        sharing;    /* file sharing mode */
  40 };
  41
  42 #define NAME_HASH_SIZE 37
  43
  44 static struct file *file_hash[NAME_HASH_SIZE];
  45
  46 static void file_dump( struct object *obj, int verbose );
  47 static int file_get_poll_events( struct object *obj );
  48 static int file_get_fd( struct object *obj );
  49 static int file_flush( struct object *obj );
  50 static int file_get_info( struct object *obj, struct get_file_info_request *req );
  51 static void file_destroy( struct object *obj );
  52
  53 static const struct object_ops file_ops =
  54 {
  55     sizeof(struct file),          /* size */
  56     file_dump,                    /* dump */
  57     default_poll_add_queue,       /* add_queue */
  58     default_poll_remove_queue,    /* remove_queue */
  59     default_poll_signaled,        /* signaled */
  60     no_satisfied,                 /* satisfied */
  61     file_get_poll_events,         /* get_poll_events */
  62     default_poll_event,           /* poll_event */
  63     file_get_fd,                  /* get_fd */
  64     file_flush,                   /* flush */
  65     file_get_info,                /* get_file_info */
  66     file_destroy                  /* destroy */
  67 };
  68
  69
  70 static int get_name_hash( const char *name )
  71 {
  72     int hash = 0;
  73     while (*name) hash ^= (unsigned char)*name++;
  74     return hash % NAME_HASH_SIZE;
  75 }
  76
  77 /* check if the desired access is possible without violating */
  78 /* the sharing mode of other opens of the same file */
  79 static int check_sharing( const char *name, int hash, unsigned int access,
  80                           unsigned int sharing )
  81 {
  82     struct file *file;
  83     unsigned int existing_sharing = FILE_SHARE_READ | FILE_SHARE_WRITE;
  84     unsigned int existing_access = 0;
  85
  86     for (file = file_hash[hash]; file; file = file->next)
  87     {
  88         if (strcmp( file->name, name )) continue;
  89         existing_sharing &= file->sharing;
  90         existing_access |= file->access;
  91     }
  92     if ((access & GENERIC_READ) && !(existing_sharing & FILE_SHARE_READ)) goto error;
  93     if ((access & GENERIC_WRITE) && !(existing_sharing & FILE_SHARE_WRITE)) goto error;
  94     if ((existing_access & GENERIC_READ) && !(sharing & FILE_SHARE_READ)) goto error;
  95     if ((existing_access & GENERIC_WRITE) && !(sharing & FILE_SHARE_WRITE)) goto error;
  96     return 1;
  97  error:
  98     set_error( STATUS_SHARING_VIOLATION );
  99     return 0;
 100 }
 101
 102 /* create a file from a file descriptor */
 103 /* if the function fails the fd is closed */
 104 static struct file *create_file_for_fd( int fd, unsigned int access, unsigned int sharing,
 105                                         unsigned int attrs )
 106 {
 107     struct file *file;
 108     if ((file = alloc_object( &file_ops, fd )))
 109     {
 110         file->name    = NULL;
 111         file->next    = NULL;
 112         file->access  = access;
 113         file->flags   = attrs;
 114         file->sharing = sharing;
 115     }
 116     return file;
 117 }
 118
 119
 120 static struct file *create_file( const char *nameptr, size_t len, unsigned int access,
 121                                  unsigned int sharing, int create, unsigned int attrs )
 122 {
 123     struct file *file;
 124     int hash, flags;
 125     struct stat st;
 126     char *name;
 127     int fd = -1;
 128
 129     if (!(name = mem_alloc( len + 1 ))) return NULL;
 130     memcpy( name, nameptr, len );
 131     name[len] = 0;
 132
 133     /* check sharing mode */
 134     hash = get_name_hash( name );
 135     if (!check_sharing( name, hash, access, sharing )) goto error;
 136
 137     switch(create)
 138     {
 139     case CREATE_NEW:        flags = O_CREAT | O_EXCL; break;
 140     case CREATE_ALWAYS:     flags = O_CREAT | O_TRUNC; break;
 141     case OPEN_ALWAYS:       flags = O_CREAT; break;
 142     case TRUNCATE_EXISTING: flags = O_TRUNC; break;
 143     case OPEN_EXISTING:     flags = 0; break;
 144     default:                set_error( STATUS_INVALID_PARAMETER ); goto error;
 145     }
 146     switch(access & (GENERIC_READ | GENERIC_WRITE))
 147     {
 148     case 0: break;
 149     case GENERIC_READ:  flags |= O_RDONLY; break;
 150     case GENERIC_WRITE: flags |= O_WRONLY; break;
 151     case GENERIC_READ|GENERIC_WRITE: flags |= O_RDWR; break;
 152     }
 153
 154     /* FIXME: should set error to STATUS_OBJECT_NAME_COLLISION if file existed before */
 155     if ((fd = open( name, flags | O_NONBLOCK,
 156                     (attrs & FILE_ATTRIBUTE_READONLY) ? 0444 : 0666 )) == -1)
 157         goto file_error;
 158     /* refuse to open a directory */
 159     if (fstat( fd, &st ) == -1) goto file_error;
 160     if (S_ISDIR(st.st_mode))
 161     {
 162         set_error( STATUS_ACCESS_DENIED );
 163         goto error;
 164     }
 165
 166     if (!(file = create_file_for_fd( fd, access, sharing, attrs )))
 167     {
 168         free( name );
 169         return NULL;
 170     }
 171     file->name = name;
 172     file->next = file_hash[hash];
 173     file_hash[hash] = file;
 174     return file;
 175
 176  file_error:
 177     file_set_error();
 178  error:
 179     if (fd != -1) close( fd );
 180     free( name );
 181     return NULL;
 182 }
 183
 184 /* Create an anonymous Unix file */
 185 int create_anonymous_file(void)
 186 {
 187     char *name;
 188     int fd;
 189
 190     do
 191     {
 192         if (!(name = tmpnam(NULL)))
 193         {
 194             set_error( STATUS_TOO_MANY_OPENED_FILES );
 195             return -1;
 196         }
 197         fd = open( name, O_CREAT | O_EXCL | O_RDWR, 0600 );
 198     } while ((fd == -1) && (errno == EEXIST));
 199     if (fd == -1)
 200     {
 201         file_set_error();
 202         return -1;
 203     }
 204     unlink( name );
 205     return fd;
 206 }
 207
 208 /* Create a temp file for anonymous mappings */
 209 struct file *create_temp_file( int access )
 210 {
 211     int fd;
 212
 213     if ((fd = create_anonymous_file()) == -1) return NULL;
 214     return create_file_for_fd( fd, access, 0, 0 );
 215 }
 216
 217 static void file_dump( struct object *obj, int verbose )
 218 {
 219     struct file *file = (struct file *)obj;
 220     assert( obj->ops == &file_ops );
 221     fprintf( stderr, "File fd=%d flags=%08x name='%s'\n", file->obj.fd, file->flags, file->name );
 222 }
 223
 224 static int file_get_poll_events( struct object *obj )
 225 {
 226     struct file *file = (struct file *)obj;
 227     int events = 0;
 228     assert( obj->ops == &file_ops );
 229     if (file->access & GENERIC_READ) events |= POLLIN;
 230     if (file->access & GENERIC_WRITE) events |= POLLOUT;
 231     return events;
 232 }
 233
 234 static int file_get_fd( struct object *obj )
 235 {
 236     struct file *file = (struct file *)obj;
 237     assert( obj->ops == &file_ops );
 238     return file->obj.fd;
 239 }
 240
 241 static int file_flush( struct object *obj )
 242 {
 243     int ret;
 244     struct file *file = (struct file *)grab_object(obj);
 245     assert( obj->ops == &file_ops );
 246
 247     ret = (fsync( file->obj.fd ) != -1);
 248     if (!ret) file_set_error();
 249     release_object( file );
 250     return ret;
 251 }
 252
 253 static int file_get_info( struct object *obj, struct get_file_info_request *req )
 254 {
 255     struct stat st;
 256     struct file *file = (struct file *)obj;
 257     assert( obj->ops == &file_ops );
 258
 259     if (fstat( file->obj.fd, &st ) == -1)
 260     {
 261         file_set_error();
 262         return 0;
 263     }
 264     if (S_ISCHR(st.st_mode) || S_ISFIFO(st.st_mode) ||
 265         S_ISSOCK(st.st_mode) || isatty(file->obj.fd)) req->type = FILE_TYPE_CHAR;
 266     else req->type = FILE_TYPE_DISK;
 267     if (S_ISDIR(st.st_mode)) req->attr = FILE_ATTRIBUTE_DIRECTORY;
 268     else req->attr = FILE_ATTRIBUTE_ARCHIVE;
 269     if (!(st.st_mode & S_IWUSR)) req->attr |= FILE_ATTRIBUTE_READONLY;
 270     req->access_time = st.st_atime;
 271     req->write_time  = st.st_mtime;
 272     req->size_high   = 0;
 273     req->size_low    = S_ISDIR(st.st_mode) ? 0 : st.st_size;
 274     req->links       = st.st_nlink;
 275     req->index_high  = st.st_dev;
 276     req->index_low   = st.st_ino;
 277     req->serial      = 0; /* FIXME */
 278     return 1;
 279 }
 280
 281 static void file_destroy( struct object *obj )
 282 {
 283     struct file *file = (struct file *)obj;
 284     assert( obj->ops == &file_ops );
 285
 286     if (file->name)
 287     {
 288         /* remove it from the hashing list */
 289         struct file **pptr = &file_hash[get_name_hash( file->name )];
 290         while (*pptr && *pptr != file) pptr = &(*pptr)->next;
 291         assert( *pptr );
 292         *pptr = (*pptr)->next;
 293         if (file->flags & FILE_FLAG_DELETE_ON_CLOSE) unlink( file->name );
 294         free( file->name );
 295     }
 296 }
 297
 298 /* set the last error depending on errno */
 299 void file_set_error(void)
 300 {
 301     switch (errno)
 302     {
 303     case EAGAIN:    set_error( STATUS_SHARING_VIOLATION ); break;
 304     case EBADF:     set_error( STATUS_INVALID_HANDLE ); break;
 305     case ENOSPC:    set_error( STATUS_DISK_FULL ); break;
 306     case EACCES:
 307     case EPERM:     set_error( STATUS_ACCESS_DENIED ); break;
 308     case EROFS:     set_error( STATUS_MEDIA_WRITE_PROTECTED ); break;
 309     case EBUSY:     set_error( STATUS_FILE_LOCK_CONFLICT ); break;
 310     case ENOENT:    set_error( STATUS_NO_SUCH_FILE ); break;
 311     case EISDIR:    set_error( 0xc0010000 | ERROR_CANNOT_MAKE /* FIXME */ ); break;
 312     case ENFILE:
 313     case EMFILE:    set_error( STATUS_NO_MORE_FILES ); break;
 314     case EEXIST:    set_error( STATUS_OBJECT_NAME_COLLISION ); break;
 315     case EINVAL:    set_error( STATUS_INVALID_PARAMETER ); break;
 316     case ESPIPE:    set_error( 0xc0010000 | ERROR_SEEK /* FIXME */ ); break;
 317     case ENOTEMPTY: set_error( STATUS_DIRECTORY_NOT_EMPTY ); break;
 318     case EIO:       set_error( STATUS_ACCESS_VIOLATION ); break;
 319     default:        perror("file_set_error"); set_error( ERROR_UNKNOWN /* FIXME */ ); break;
 320     }
 321 }
 322
 323 struct file *get_file_obj( struct process *process, handle_t handle, unsigned int access )
 324 {
 325     return (struct file *)get_handle_obj( process, handle, access, &file_ops );
 326 }
 327
 328 static int set_file_pointer( handle_t handle, int *low, int *high, int whence )
 329 {
 330     struct file *file;
 331     int result;
 332
 333     if ((*low >= 0 && *high != 0) || (*low < 0 && *high != -1))
 334     {
 335         fprintf( stderr, "set_file_pointer: offset > 2Gb not supported yet\n" );
 336         set_error( STATUS_INVALID_PARAMETER );
 337         return 0;
 338     }
 339
 340     if (!(file = get_file_obj( current->process, handle, 0 )))
 341         return 0;
 342     if ((result = lseek( file->obj.fd, *low, whence )) == -1)
 343     {
 344         /* Check for seek before start of file */
 345
 346         /* also check EPERM due to SuSE7 2.2.16 lseek() EPERM kernel bug */
 347         if (((errno == EINVAL) || (errno == EPERM))
 348             && (whence != SEEK_SET) && (*low < 0))
 349             set_error( 0xc0010000 | ERROR_NEGATIVE_SEEK /* FIXME */ );
 350         else
 351             file_set_error();
 352         release_object( file );
 353         return 0;
 354     }
 355     *low = result;
 356     release_object( file );
 357     return 1;
 358 }
 359
 360 static int truncate_file( handle_t handle )
 361 {
 362     struct file *file;
 363     int result;
 364
 365     if (!(file = get_file_obj( current->process, handle, GENERIC_WRITE )))
 366         return 0;
 367     if (((result = lseek( file->obj.fd, 0, SEEK_CUR )) == -1) ||
 368         (ftruncate( file->obj.fd, result ) == -1))
 369     {
 370         file_set_error();
 371         release_object( file );
 372         return 0;
 373     }
 374     release_object( file );
 375     return 1;
 376 }
 377
 378 /* try to grow the file to the specified size */
 379 int grow_file( struct file *file, int size_high, int size_low )
 380 {
 381     struct stat st;
 382
 383     if (size_high)
 384     {
 385         set_error( STATUS_INVALID_PARAMETER );
 386         return 0;
 387     }
 388     if (fstat( file->obj.fd, &st ) == -1)
 389     {
 390         file_set_error();
 391         return 0;
 392     }
 393     if (st.st_size >= size_low) return 1;  /* already large enough */
 394     if (ftruncate( file->obj.fd, size_low ) != -1) return 1;
 395     file_set_error();
 396     return 0;
 397 }
 398
 399 static int set_file_time( handle_t handle, time_t access_time, time_t write_time )
 400 {
 401     struct file *file;
 402     struct utimbuf utimbuf;
 403
 404     if (!(file = get_file_obj( current->process, handle, GENERIC_WRITE )))
 405         return 0;
 406     if (!file->name)
 407     {
 408         set_error( STATUS_INVALID_HANDLE );
 409         release_object( file );
 410         return 0;
 411     }
 412     if (!access_time || !write_time)
 413     {
 414         struct stat st;
 415         if (stat( file->name, &st ) == -1) goto error;
 416         if (!access_time) access_time = st.st_atime;
 417         if (!write_time) write_time = st.st_mtime;
 418     }
 419     utimbuf.actime  = access_time;
 420     utimbuf.modtime = write_time;
 421     if (utime( file->name, &utimbuf ) == -1) goto error;
 422     release_object( file );
 423     return 1;
 424  error:
 425     file_set_error();
 426     release_object( file );
 427     return 0;
 428 }
 429
 430 static int file_lock( struct file *file, int offset_high, int offset_low,
 431                       int count_high, int count_low )
 432 {
 433     /* FIXME: implement this */
 434     return 1;
 435 }
 436
 437 static int file_unlock( struct file *file, int offset_high, int offset_low,
 438                         int count_high, int count_low )
 439 {
 440     /* FIXME: implement this */
 441     return 1;
 442 }
 443
 444 /* create a file */
 445 DECL_HANDLER(create_file)
 446 {
 447     struct file *file;
 448
 449     req->handle = 0;
 450     if ((file = create_file( get_req_data(req), get_req_data_size(req), req->access,
 451                              req->sharing, req->create, req->attrs )))
 452     {
 453         req->handle = alloc_handle( current->process, file, req->access, req->inherit );
 454         release_object( file );
 455     }
 456 }
 457
 458 /* allocate a file handle for a Unix fd */
 459 DECL_HANDLER(alloc_file_handle)
 460 {
 461     struct file *file;
 462     int fd;
 463
 464     req->handle = 0;
 465     if ((fd = thread_get_inflight_fd( current, req->fd )) == -1)
 466     {
 467         set_error( STATUS_INVALID_HANDLE );
 468         return;
 469     }
 470     if ((file = create_file_for_fd( fd, req->access, FILE_SHARE_READ | FILE_SHARE_WRITE, 0 )))
 471     {
 472         req->handle = alloc_handle( current->process, file, req->access, 0 );
 473         release_object( file );
 474     }
 475 }
 476
 477 /* get a Unix fd to access a file */
 478 DECL_HANDLER(get_handle_fd)
 479 {
 480     struct object *obj;
 481
 482     req->fd = -1;
 483     if ((obj = get_handle_obj( current->process, req->handle, req->access, NULL )))
 484     {
 485         int fd = get_handle_fd( current->process, req->handle, req->access );
 486         if (fd != -1) req->fd = fd;
 487         else if (!get_error())
 488         {
 489             if ((fd = obj->ops->get_fd( obj )) != -1)
 490                 send_client_fd( current->process, fd, req->handle );
 491         }
 492         release_object( obj );
 493     }
 494 }
 495
 496 /* set a file current position */
 497 DECL_HANDLER(set_file_pointer)
 498 {
 499     int high = req->high;
 500     int low  = req->low;
 501     set_file_pointer( req->handle, &low, &high, req->whence );
 502     req->new_low  = low;
 503     req->new_high = high;
 504 }
 505
 506 /* truncate (or extend) a file */
 507 DECL_HANDLER(truncate_file)
 508 {
 509     truncate_file( req->handle );
 510 }
 511
 512 /* flush a file buffers */
 513 DECL_HANDLER(flush_file)
 514 {
 515     struct object *obj;
 516
 517     if ((obj = get_handle_obj( current->process, req->handle, 0, NULL )))
 518     {
 519         obj->ops->flush( obj );
 520         release_object( obj );
 521     }
 522 }
 523
 524 /* set a file access and modification times */
 525 DECL_HANDLER(set_file_time)
 526 {
 527     set_file_time( req->handle, req->access_time, req->write_time );
 528 }
 529
 530 /* get a file information */
 531 DECL_HANDLER(get_file_info)
 532 {
 533     struct object *obj;
 534
 535     if ((obj = get_handle_obj( current->process, req->handle, 0, NULL )))
 536     {
 537         obj->ops->get_file_info( obj, req );
 538         release_object( obj );
 539     }
 540 }
 541
 542 /* lock a region of a file */
 543 DECL_HANDLER(lock_file)
 544 {
 545     struct file *file;
 546
 547     if ((file = get_file_obj( current->process, req->handle, 0 )))
 548     {
 549         file_lock( file, req->offset_high, req->offset_low,
 550                    req->count_high, req->count_low );
 551         release_object( file );
 552     }
 553 }
 554
 555 /* unlock a region of a file */
 556 DECL_HANDLER(unlock_file)
 557 {
 558     struct file *file;
 559
 560     if ((file = get_file_obj( current->process, req->handle, 0 )))
 561     {
 562         file_unlock( file, req->offset_high, req->offset_low,
 563                      req->count_high, req->count_low );
 564         release_object( file );
 565     }
 566 }